mirror of
https://git.FreeBSD.org/src.git
synced 2024-12-05 09:14:03 +00:00
Update to zlib 1.2.4 and add versioned symbols to the
library. Sponsored by: iXsystems, Inc.
This commit is contained in:
parent
c9cefec159
commit
798aea00f8
Notes:
svn2git
2020-12-20 02:59:44 +00:00
svn path=/head/; revision=205471
@ -14,6 +14,11 @@
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# The file is partitioned: OLD_FILES first, then OLD_LIBS and OLD_DIRS last.
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#
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# 20100322: libz update
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OLD_LIBS+=lib/libz.so.5
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.if ${TARGET_ARCH} == "amd64"
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OLD_LIBS+=usr/lib32/libz.so.5
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.endif
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# 20100314: removal of regexp.h
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OLD_FILES+=usr/include/regexp.h
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OLD_FILES+=usr/share/man/man3/regexp.3.gz
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@ -1,6 +1,281 @@
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ChangeLog file for zlib
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Changes in 1.2.4 (14 Mar 2010)
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- Fix VER3 extraction in configure for no fourth subversion
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- Update zlib.3, add docs to Makefile.in to make .pdf out of it
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- Add zlib.3.pdf to distribution
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- Don't set error code in gzerror() if passed pointer is NULL
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- Apply destination directory fixes to CMakeLists.txt [Lowman]
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- Move #cmakedefine's to a new zconf.in.cmakein
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- Restore zconf.h for builds that don't use configure or cmake
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- Add distclean to dummy Makefile for convenience
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- Update and improve INDEX, README, and FAQ
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- Update CMakeLists.txt for the return of zconf.h [Lowman]
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- Update contrib/vstudio/vc9 and vc10 [Vollant]
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- Change libz.dll.a back to libzdll.a in win32/Makefile.gcc
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- Apply license and readme changes to contrib/asm686 [Raiter]
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- Check file name lengths and add -c option in minigzip.c [Li]
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- Update contrib/amd64 and contrib/masmx86/ [Vollant]
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- Avoid use of "eof" parameter in trees.c to not shadow library variable
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- Update make_vms.com for removal of zlibdefs.h [Zinser]
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- Update assembler code and vstudio projects in contrib [Vollant]
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- Remove outdated assembler code contrib/masm686 and contrib/asm586
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- Remove old vc7 and vc8 from contrib/vstudio
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- Update win32/Makefile.msc, add ZLIB_VER_SUBREVISION [Rowe]
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- Fix memory leaks in gzclose_r() and gzclose_w(), file leak in gz_open()
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- Add contrib/gcc_gvmat64 for longest_match and inflate_fast [Vollant]
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- Remove *64 functions from win32/zlib.def (they're not 64-bit yet)
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- Fix bug in void-returning vsprintf() case in gzwrite.c
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- Fix name change from inflate.h in contrib/inflate86/inffas86.c
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- Check if temporary file exists before removing in make_vms.com [Zinser]
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- Fix make install and uninstall for --static option
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- Fix usage of _MSC_VER in gzguts.h and zutil.h [Truta]
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- Update readme.txt in contrib/masmx64 and masmx86 to assemble
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Changes in 1.2.3.9 (21 Feb 2010)
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- Expunge gzio.c
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- Move as400 build information to old
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- Fix updates in contrib/minizip and contrib/vstudio
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- Add const to vsnprintf test in configure to avoid warnings [Weigelt]
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- Delete zconf.h (made by configure) [Weigelt]
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- Change zconf.in.h to zconf.h.in per convention [Weigelt]
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- Check for NULL buf in gzgets()
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- Return empty string for gzgets() with len == 1 (like fgets())
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- Fix description of gzgets() in zlib.h for end-of-file, NULL return
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- Update minizip to 1.1 [Vollant]
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- Avoid MSVC loss of data warnings in gzread.c, gzwrite.c
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- Note in zlib.h that gzerror() should be used to distinguish from EOF
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- Remove use of snprintf() from gzlib.c
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- Fix bug in gzseek()
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- Update contrib/vstudio, adding vc9 and vc10 [Kuno, Vollant]
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- Fix zconf.h generation in CMakeLists.txt [Lowman]
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- Improve comments in zconf.h where modified by configure
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Changes in 1.2.3.8 (13 Feb 2010)
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- Clean up text files (tabs, trailing whitespace, etc.) [Oberhumer]
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- Use z_off64_t in gz_zero() and gz_skip() to match state->skip
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- Avoid comparison problem when sizeof(int) == sizeof(z_off64_t)
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- Revert to Makefile.in from 1.2.3.6 (live with the clutter)
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- Fix missing error return in gzflush(), add zlib.h note
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- Add *64 functions to zlib.map [Levin]
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- Fix signed/unsigned comparison in gz_comp()
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- Use SFLAGS when testing shared linking in configure
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- Add --64 option to ./configure to use -m64 with gcc
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- Fix ./configure --help to correctly name options
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- Have make fail if a test fails [Levin]
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- Avoid buffer overrun in contrib/masmx64/gvmat64.asm [Simpson]
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- Remove assembler object files from contrib
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Changes in 1.2.3.7 (24 Jan 2010)
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- Always gzopen() with O_LARGEFILE if available
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- Fix gzdirect() to work immediately after gzopen() or gzdopen()
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- Make gzdirect() more precise when the state changes while reading
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- Improve zlib.h documentation in many places
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- Catch memory allocation failure in gz_open()
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- Complete close operation if seek forward in gzclose_w() fails
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- Return Z_ERRNO from gzclose_r() if close() fails
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- Return Z_STREAM_ERROR instead of EOF for gzclose() being passed NULL
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- Return zero for gzwrite() errors to match zlib.h description
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- Return -1 on gzputs() error to match zlib.h description
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- Add zconf.in.h to allow recovery from configure modification [Weigelt]
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- Fix static library permissions in Makefile.in [Weigelt]
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- Avoid warnings in configure tests that hide functionality [Weigelt]
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- Add *BSD and DragonFly to Linux case in configure [gentoo 123571]
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- Change libzdll.a to libz.dll.a in win32/Makefile.gcc [gentoo 288212]
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- Avoid access of uninitialized data for first inflateReset2 call [Gomes]
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- Keep object files in subdirectories to reduce the clutter somewhat
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- Remove default Makefile and zlibdefs.h, add dummy Makefile
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- Add new external functions to Z_PREFIX, remove duplicates, z_z_ -> z_
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- Remove zlibdefs.h completely -- modify zconf.h instead
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Changes in 1.2.3.6 (17 Jan 2010)
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- Avoid void * arithmetic in gzread.c and gzwrite.c
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- Make compilers happier with const char * for gz_error message
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- Avoid unused parameter warning in inflate.c
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- Avoid signed-unsigned comparison warning in inflate.c
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- Indent #pragma's for traditional C
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- Fix usage of strwinerror() in glib.c, change to gz_strwinerror()
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- Correct email address in configure for system options
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- Update make_vms.com and add make_vms.com to contrib/minizip [Zinser]
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- Update zlib.map [Brown]
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- Fix Makefile.in for Solaris 10 make of example64 and minizip64 [Tšršk]
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- Apply various fixes to CMakeLists.txt [Lowman]
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- Add checks on len in gzread() and gzwrite()
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- Add error message for no more room for gzungetc()
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- Remove zlib version check in gzwrite()
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- Defer compression of gzprintf() result until need to
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- Use snprintf() in gzdopen() if available
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- Remove USE_MMAP configuration determination (only used by minigzip)
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- Remove examples/pigz.c (available separately)
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- Update examples/gun.c to 1.6
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Changes in 1.2.3.5 (8 Jan 2010)
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- Add space after #if in zutil.h for some compilers
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- Fix relatively harmless bug in deflate_fast() [Exarevsky]
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- Fix same problem in deflate_slow()
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- Add $(SHAREDLIBV) to LIBS in Makefile.in [Brown]
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- Add deflate_rle() for faster Z_RLE strategy run-length encoding
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- Add deflate_huff() for faster Z_HUFFMAN_ONLY encoding
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- Change name of "write" variable in inffast.c to avoid library collisions
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- Fix premature EOF from gzread() in gzio.c [Brown]
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- Use zlib header window size if windowBits is 0 in inflateInit2()
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- Remove compressBound() call in deflate.c to avoid linking compress.o
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- Replace use of errno in gz* with functions, support WinCE [Alves]
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- Provide alternative to perror() in minigzip.c for WinCE [Alves]
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- Don't use _vsnprintf on later versions of MSVC [Lowman]
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- Add CMake build script and input file [Lowman]
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- Update contrib/minizip to 1.1 [Svensson, Vollant]
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- Moved nintendods directory from contrib to .
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- Replace gzio.c with a new set of routines with the same functionality
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- Add gzbuffer(), gzoffset(), gzclose_r(), gzclose_w() as part of above
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- Update contrib/minizip to 1.1b
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- Change gzeof() to return 0 on error instead of -1 to agree with zlib.h
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Changes in 1.2.3.4 (21 Dec 2009)
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- Use old school .SUFFIXES in Makefile.in for FreeBSD compatibility
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- Update comments in configure and Makefile.in for default --shared
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- Fix test -z's in configure [Marquess]
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- Build examplesh and minigzipsh when not testing
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- Change NULL's to Z_NULL's in deflate.c and in comments in zlib.h
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- Import LDFLAGS from the environment in configure
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- Fix configure to populate SFLAGS with discovered CFLAGS options
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- Adapt make_vms.com to the new Makefile.in [Zinser]
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- Add zlib2ansi script for C++ compilation [Marquess]
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- Add _FILE_OFFSET_BITS=64 test to make test (when applicable)
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- Add AMD64 assembler code for longest match to contrib [Teterin]
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- Include options from $SFLAGS when doing $LDSHARED
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- Simplify 64-bit file support by introducing z_off64_t type
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- Make shared object files in objs directory to work around old Sun cc
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- Use only three-part version number for Darwin shared compiles
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- Add rc option to ar in Makefile.in for when ./configure not run
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- Add -WI,-rpath,. to LDFLAGS for OSF 1 V4*
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- Set LD_LIBRARYN32_PATH for SGI IRIX shared compile
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- Protect against _FILE_OFFSET_BITS being defined when compiling zlib
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- Rename Makefile.in targets allstatic to static and allshared to shared
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- Fix static and shared Makefile.in targets to be independent
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- Correct error return bug in gz_open() by setting state [Brown]
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- Put spaces before ;;'s in configure for better sh compatibility
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- Add pigz.c (parallel implementation of gzip) to examples/
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- Correct constant in crc32.c to UL [Leventhal]
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- Reject negative lengths in crc32_combine()
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- Add inflateReset2() function to work like inflateEnd()/inflateInit2()
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- Include sys/types.h for _LARGEFILE64_SOURCE [Brown]
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- Correct typo in doc/algorithm.txt [Janik]
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- Fix bug in adler32_combine() [Zhu]
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- Catch missing-end-of-block-code error in all inflates and in puff
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Assures that random input to inflate eventually results in an error
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- Added enough.c (calculation of ENOUGH for inftrees.h) to examples/
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- Update ENOUGH and its usage to reflect discovered bounds
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- Fix gzerror() error report on empty input file [Brown]
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- Add ush casts in trees.c to avoid pedantic runtime errors
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- Fix typo in zlib.h uncompress() description [Reiss]
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- Correct inflate() comments with regard to automatic header detection
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- Remove deprecation comment on Z_PARTIAL_FLUSH (it stays)
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- Put new version of gzlog (2.0) in examples with interruption recovery
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- Add puff compile option to permit invalid distance-too-far streams
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- Add puff TEST command options, ability to read piped input
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- Prototype the *64 functions in zlib.h when _FILE_OFFSET_BITS == 64, but
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_LARGEFILE64_SOURCE not defined
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- Fix Z_FULL_FLUSH to truly erase the past by resetting s->strstart
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- Fix deflateSetDictionary() to use all 32K for output consistency
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- Remove extraneous #define MIN_LOOKAHEAD in deflate.c (in deflate.h)
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- Clear bytes after deflate lookahead to avoid use of uninitialized data
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- Change a limit in inftrees.c to be more transparent to Coverity Prevent
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- Update win32/zlib.def with exported symbols from zlib.h
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- Correct spelling error in zlib.h [Willem]
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- Allow Z_BLOCK for deflate() to force a new block
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- Allow negative bits in inflatePrime() to delete existing bit buffer
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- Add Z_TREES flush option to inflate() to return at end of trees
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- Add inflateMark() to return current state information for random access
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- Add Makefile for NintendoDS to contrib [Costa]
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- Add -w in configure compile tests to avoid spurious warnings [Beucler]
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- Fix typos in zlib.h comments for deflateSetDictionary()
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- Fix EOF detection in transparent gzread() [Maier]
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Changes in 1.2.3.3 (2 October 2006)
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- Make --shared the default for configure, add a --static option
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- Add compile option to permit invalid distance-too-far streams
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- Add inflateUndermine() function which is required to enable above
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- Remove use of "this" variable name for C++ compatibility [Marquess]
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- Add testing of shared library in make test, if shared library built
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- Use ftello() and fseeko() if available instead of ftell() and fseek()
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- Provide two versions of all functions that use the z_off_t type for
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binary compatibility -- a normal version and a 64-bit offset version,
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per the Large File Support Extension when _LARGEFILE64_SOURCE is
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defined; use the 64-bit versions by default when _FILE_OFFSET_BITS
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is defined to be 64
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- Add a --uname= option to configure to perhaps help with cross-compiling
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Changes in 1.2.3.2 (3 September 2006)
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- Turn off silly Borland warnings [Hay]
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- Use off64_t and define _LARGEFILE64_SOURCE when present
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- Fix missing dependency on inffixed.h in Makefile.in
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- Rig configure --shared to build both shared and static [Teredesai, Truta]
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- Remove zconf.in.h and instead create a new zlibdefs.h file
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- Fix contrib/minizip/unzip.c non-encrypted after encrypted [Vollant]
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- Add treebuild.xml (see http://treebuild.metux.de/) [Weigelt]
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Changes in 1.2.3.1 (16 August 2006)
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- Add watcom directory with OpenWatcom make files [Daniel]
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- Remove #undef of FAR in zconf.in.h for MVS [Fedtke]
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- Update make_vms.com [Zinser]
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- Use -fPIC for shared build in configure [Teredesai, Nicholson]
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- Use only major version number for libz.so on IRIX and OSF1 [Reinholdtsen]
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- Use fdopen() (not _fdopen()) for Interix in zutil.h [BŠck]
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- Add some FAQ entries about the contrib directory
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- Update the MVS question in the FAQ
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- Avoid extraneous reads after EOF in gzio.c [Brown]
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- Correct spelling of "successfully" in gzio.c [Randers-Pehrson]
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- Add comments to zlib.h about gzerror() usage [Brown]
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- Set extra flags in gzip header in gzopen() like deflate() does
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- Make configure options more compatible with double-dash conventions
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[Weigelt]
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- Clean up compilation under Solaris SunStudio cc [Rowe, Reinholdtsen]
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- Fix uninstall target in Makefile.in [Truta]
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- Add pkgconfig support [Weigelt]
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- Use $(DESTDIR) macro in Makefile.in [Reinholdtsen, Weigelt]
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- Replace set_data_type() with a more accurate detect_data_type() in
|
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trees.c, according to the txtvsbin.txt document [Truta]
|
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- Swap the order of #include <stdio.h> and #include "zlib.h" in
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gzio.c, example.c and minigzip.c [Truta]
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- Shut up annoying VS2005 warnings about standard C deprecation [Rowe,
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Truta] (where?)
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- Fix target "clean" from win32/Makefile.bor [Truta]
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- Create .pdb and .manifest files in win32/makefile.msc [Ziegler, Rowe]
|
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- Update zlib www home address in win32/DLL_FAQ.txt [Truta]
|
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- Update contrib/masmx86/inffas32.asm for VS2005 [Vollant, Van Wassenhove]
|
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- Enable browse info in the "Debug" and "ASM Debug" configurations in
|
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the Visual C++ 6 project, and set (non-ASM) "Debug" as default [Truta]
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- Add pkgconfig support [Weigelt]
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- Add ZLIB_VER_MAJOR, ZLIB_VER_MINOR and ZLIB_VER_REVISION in zlib.h,
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for use in win32/zlib1.rc [Polushin, Rowe, Truta]
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- Add a document that explains the new text detection scheme to
|
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doc/txtvsbin.txt [Truta]
|
||||
- Add rfc1950.txt, rfc1951.txt and rfc1952.txt to doc/ [Truta]
|
||||
- Move algorithm.txt into doc/ [Truta]
|
||||
- Synchronize FAQ with website
|
||||
- Fix compressBound(), was low for some pathological cases [Fearnley]
|
||||
- Take into account wrapper variations in deflateBound()
|
||||
- Set examples/zpipe.c input and output to binary mode for Windows
|
||||
- Update examples/zlib_how.html with new zpipe.c (also web site)
|
||||
- Fix some warnings in examples/gzlog.c and examples/zran.c (it seems
|
||||
that gcc became pickier in 4.0)
|
||||
- Add zlib.map for Linux: "All symbols from zlib-1.1.4 remain
|
||||
un-versioned, the patch adds versioning only for symbols introduced in
|
||||
zlib-1.2.0 or later. It also declares as local those symbols which are
|
||||
not designed to be exported." [Levin]
|
||||
- Update Z_PREFIX list in zconf.in.h, add --zprefix option to configure
|
||||
- Do not initialize global static by default in trees.c, add a response
|
||||
NO_INIT_GLOBAL_POINTERS to initialize them if needed [Marquess]
|
||||
- Don't use strerror() in gzio.c under WinCE [Yakimov]
|
||||
- Don't use errno.h in zutil.h under WinCE [Yakimov]
|
||||
- Move arguments for AR to its usage to allow replacing ar [Marot]
|
||||
- Add HAVE_VISIBILITY_PRAGMA in zconf.in.h for Mozilla [Randers-Pehrson]
|
||||
- Improve inflateInit() and inflateInit2() documentation
|
||||
- Fix structure size comment in inflate.h
|
||||
- Change configure help option from --h* to --help [Santos]
|
||||
|
||||
Changes in 1.2.3 (18 July 2005)
|
||||
- Apply security vulnerability fixes to contrib/infback9 as well
|
||||
- Clean up some text files (carriage returns, trailing space)
|
||||
@ -13,7 +288,7 @@ Changes in 1.2.2.4 (11 July 2005)
|
||||
compile
|
||||
- Fix some spelling errors in comments [Betts]
|
||||
- Correct inflateInit2() error return documentation in zlib.h
|
||||
- Added zran.c example of compressed data random access to examples
|
||||
- Add zran.c example of compressed data random access to examples
|
||||
directory, shows use of inflatePrime()
|
||||
- Fix cast for assignments to strm->state in inflate.c and infback.c
|
||||
- Fix zlibCompileFlags() in zutil.c to use 1L for long shifts [Oberhumer]
|
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|
261
lib/libz/FAQ
261
lib/libz/FAQ
@ -3,8 +3,8 @@
|
||||
|
||||
|
||||
If your question is not there, please check the zlib home page
|
||||
http://www.zlib.org which may have more recent information.
|
||||
The lastest zlib FAQ is at http://www.gzip.org/zlib/zlib_faq.html
|
||||
http://zlib.net/ which may have more recent information.
|
||||
The lastest zlib FAQ is at http://zlib.net/zlib_faq.html
|
||||
|
||||
|
||||
1. Is zlib Y2K-compliant?
|
||||
@ -13,54 +13,51 @@ The lastest zlib FAQ is at http://www.gzip.org/zlib/zlib_faq.html
|
||||
|
||||
2. Where can I get a Windows DLL version?
|
||||
|
||||
The zlib sources can be compiled without change to produce a DLL.
|
||||
See the file win32/DLL_FAQ.txt in the zlib distribution.
|
||||
Pointers to the precompiled DLL are found in the zlib web site at
|
||||
http://www.zlib.org.
|
||||
The zlib sources can be compiled without change to produce a DLL. See the
|
||||
file win32/DLL_FAQ.txt in the zlib distribution. Pointers to the
|
||||
precompiled DLL are found in the zlib web site at http://zlib.net/ .
|
||||
|
||||
3. Where can I get a Visual Basic interface to zlib?
|
||||
|
||||
See
|
||||
* http://www.dogma.net/markn/articles/zlibtool/zlibtool.htm
|
||||
* contrib/visual-basic.txt in the zlib distribution
|
||||
* http://marknelson.us/1997/01/01/zlib-engine/
|
||||
* win32/DLL_FAQ.txt in the zlib distribution
|
||||
|
||||
4. compress() returns Z_BUF_ERROR.
|
||||
|
||||
Make sure that before the call of compress, the length of the compressed
|
||||
buffer is equal to the total size of the compressed buffer and not
|
||||
zero. For Visual Basic, check that this parameter is passed by reference
|
||||
Make sure that before the call of compress(), the length of the compressed
|
||||
buffer is equal to the available size of the compressed buffer and not
|
||||
zero. For Visual Basic, check that this parameter is passed by reference
|
||||
("as any"), not by value ("as long").
|
||||
|
||||
5. deflate() or inflate() returns Z_BUF_ERROR.
|
||||
|
||||
Before making the call, make sure that avail_in and avail_out are not
|
||||
zero. When setting the parameter flush equal to Z_FINISH, also make sure
|
||||
that avail_out is big enough to allow processing all pending input.
|
||||
Note that a Z_BUF_ERROR is not fatal--another call to deflate() or
|
||||
inflate() can be made with more input or output space. A Z_BUF_ERROR
|
||||
may in fact be unavoidable depending on how the functions are used, since
|
||||
it is not possible to tell whether or not there is more output pending
|
||||
when strm.avail_out returns with zero.
|
||||
Before making the call, make sure that avail_in and avail_out are not zero.
|
||||
When setting the parameter flush equal to Z_FINISH, also make sure that
|
||||
avail_out is big enough to allow processing all pending input. Note that a
|
||||
Z_BUF_ERROR is not fatal--another call to deflate() or inflate() can be
|
||||
made with more input or output space. A Z_BUF_ERROR may in fact be
|
||||
unavoidable depending on how the functions are used, since it is not
|
||||
possible to tell whether or not there is more output pending when
|
||||
strm.avail_out returns with zero. See http://zlib.net/zlib_how.html for a
|
||||
heavily annotated example.
|
||||
|
||||
6. Where's the zlib documentation (man pages, etc.)?
|
||||
|
||||
It's in zlib.h for the moment, and Francis S. Lin has converted it to a
|
||||
web page zlib.html. Volunteers to transform this to Unix-style man pages,
|
||||
please contact us (zlib@gzip.org). Examples of zlib usage are in the files
|
||||
example.c and minigzip.c.
|
||||
It's in zlib.h . Examples of zlib usage are in the files example.c and
|
||||
minigzip.c, with more in examples/ .
|
||||
|
||||
7. Why don't you use GNU autoconf or libtool or ...?
|
||||
|
||||
Because we would like to keep zlib as a very small and simple
|
||||
package. zlib is rather portable and doesn't need much configuration.
|
||||
Because we would like to keep zlib as a very small and simple package.
|
||||
zlib is rather portable and doesn't need much configuration.
|
||||
|
||||
8. I found a bug in zlib.
|
||||
|
||||
Most of the time, such problems are due to an incorrect usage of
|
||||
zlib. Please try to reproduce the problem with a small program and send
|
||||
the corresponding source to us at zlib@gzip.org . Do not send
|
||||
multi-megabyte data files without prior agreement.
|
||||
Most of the time, such problems are due to an incorrect usage of zlib.
|
||||
Please try to reproduce the problem with a small program and send the
|
||||
corresponding source to us at zlib@gzip.org . Do not send multi-megabyte
|
||||
data files without prior agreement.
|
||||
|
||||
9. Why do I get "undefined reference to gzputc"?
|
||||
|
||||
@ -82,7 +79,7 @@ The lastest zlib FAQ is at http://www.gzip.org/zlib/zlib_faq.html
|
||||
|
||||
12. Can zlib handle .Z files?
|
||||
|
||||
No, sorry. You have to spawn an uncompress or gunzip subprocess, or adapt
|
||||
No, sorry. You have to spawn an uncompress or gunzip subprocess, or adapt
|
||||
the code of uncompress on your own.
|
||||
|
||||
13. How can I make a Unix shared library?
|
||||
@ -99,8 +96,10 @@ The lastest zlib FAQ is at http://www.gzip.org/zlib/zlib_faq.html
|
||||
|
||||
However, many flavors of Unix come with a shared zlib already installed.
|
||||
Before going to the trouble of compiling a shared version of zlib and
|
||||
trying to install it, you may want to check if it's already there! If you
|
||||
can #include <zlib.h>, it's there. The -lz option will probably link to it.
|
||||
trying to install it, you may want to check if it's already there! If you
|
||||
can #include <zlib.h>, it's there. The -lz option will probably link to
|
||||
it. You can check the version at the top of zlib.h or with the
|
||||
ZLIB_VERSION symbol defined in zlib.h .
|
||||
|
||||
15. I have a question about OttoPDF.
|
||||
|
||||
@ -109,8 +108,8 @@ The lastest zlib FAQ is at http://www.gzip.org/zlib/zlib_faq.html
|
||||
|
||||
16. Can zlib decode Flate data in an Adobe PDF file?
|
||||
|
||||
Yes. See http://www.fastio.com/ (ClibPDF), or http://www.pdflib.com/ .
|
||||
To modify PDF forms, see http://sourceforge.net/projects/acroformtool/ .
|
||||
Yes. See http://www.pdflib.com/ . To modify PDF forms, see
|
||||
http://sourceforge.net/projects/acroformtool/ .
|
||||
|
||||
17. Why am I getting this "register_frame_info not found" error on Solaris?
|
||||
|
||||
@ -121,67 +120,67 @@ The lastest zlib FAQ is at http://www.gzip.org/zlib/zlib_faq.html
|
||||
symbol __register_frame_info: referenced symbol not found
|
||||
|
||||
The symbol __register_frame_info is not part of zlib, it is generated by
|
||||
the C compiler (cc or gcc). You must recompile applications using zlib
|
||||
which have this problem. This problem is specific to Solaris. See
|
||||
the C compiler (cc or gcc). You must recompile applications using zlib
|
||||
which have this problem. This problem is specific to Solaris. See
|
||||
http://www.sunfreeware.com for Solaris versions of zlib and applications
|
||||
using zlib.
|
||||
|
||||
18. Why does gzip give an error on a file I make with compress/deflate?
|
||||
|
||||
The compress and deflate functions produce data in the zlib format, which
|
||||
is different and incompatible with the gzip format. The gz* functions in
|
||||
zlib on the other hand use the gzip format. Both the zlib and gzip
|
||||
formats use the same compressed data format internally, but have different
|
||||
headers and trailers around the compressed data.
|
||||
is different and incompatible with the gzip format. The gz* functions in
|
||||
zlib on the other hand use the gzip format. Both the zlib and gzip formats
|
||||
use the same compressed data format internally, but have different headers
|
||||
and trailers around the compressed data.
|
||||
|
||||
19. Ok, so why are there two different formats?
|
||||
|
||||
The gzip format was designed to retain the directory information about
|
||||
a single file, such as the name and last modification date. The zlib
|
||||
format on the other hand was designed for in-memory and communication
|
||||
channel applications, and has a much more compact header and trailer and
|
||||
uses a faster integrity check than gzip.
|
||||
The gzip format was designed to retain the directory information about a
|
||||
single file, such as the name and last modification date. The zlib format
|
||||
on the other hand was designed for in-memory and communication channel
|
||||
applications, and has a much more compact header and trailer and uses a
|
||||
faster integrity check than gzip.
|
||||
|
||||
20. Well that's nice, but how do I make a gzip file in memory?
|
||||
|
||||
You can request that deflate write the gzip format instead of the zlib
|
||||
format using deflateInit2(). You can also request that inflate decode
|
||||
the gzip format using inflateInit2(). Read zlib.h for more details.
|
||||
format using deflateInit2(). You can also request that inflate decode the
|
||||
gzip format using inflateInit2(). Read zlib.h for more details.
|
||||
|
||||
21. Is zlib thread-safe?
|
||||
|
||||
Yes. However any library routines that zlib uses and any application-
|
||||
provided memory allocation routines must also be thread-safe. zlib's gz*
|
||||
Yes. However any library routines that zlib uses and any application-
|
||||
provided memory allocation routines must also be thread-safe. zlib's gz*
|
||||
functions use stdio library routines, and most of zlib's functions use the
|
||||
library memory allocation routines by default. zlib's Init functions allow
|
||||
for the application to provide custom memory allocation routines.
|
||||
library memory allocation routines by default. zlib's *Init* functions
|
||||
allow for the application to provide custom memory allocation routines.
|
||||
|
||||
Of course, you should only operate on any given zlib or gzip stream from a
|
||||
single thread at a time.
|
||||
|
||||
22. Can I use zlib in my commercial application?
|
||||
|
||||
Yes. Please read the license in zlib.h.
|
||||
Yes. Please read the license in zlib.h.
|
||||
|
||||
23. Is zlib under the GNU license?
|
||||
|
||||
No. Please read the license in zlib.h.
|
||||
No. Please read the license in zlib.h.
|
||||
|
||||
24. The license says that altered source versions must be "plainly marked". So
|
||||
what exactly do I need to do to meet that requirement?
|
||||
|
||||
You need to change the ZLIB_VERSION and ZLIB_VERNUM #defines in zlib.h. In
|
||||
You need to change the ZLIB_VERSION and ZLIB_VERNUM #defines in zlib.h. In
|
||||
particular, the final version number needs to be changed to "f", and an
|
||||
identification string should be appended to ZLIB_VERSION. Version numbers
|
||||
identification string should be appended to ZLIB_VERSION. Version numbers
|
||||
x.x.x.f are reserved for modifications to zlib by others than the zlib
|
||||
maintainers. For example, if the version of the base zlib you are altering
|
||||
maintainers. For example, if the version of the base zlib you are altering
|
||||
is "1.2.3.4", then in zlib.h you should change ZLIB_VERNUM to 0x123f, and
|
||||
ZLIB_VERSION to something like "1.2.3.f-zachary-mods-v3". You can also
|
||||
ZLIB_VERSION to something like "1.2.3.f-zachary-mods-v3". You can also
|
||||
update the version strings in deflate.c and inftrees.c.
|
||||
|
||||
For altered source distributions, you should also note the origin and
|
||||
nature of the changes in zlib.h, as well as in ChangeLog and README, along
|
||||
with the dates of the alterations. The origin should include at least your
|
||||
with the dates of the alterations. The origin should include at least your
|
||||
name (or your company's name), and an email address to contact for help or
|
||||
issues with the library.
|
||||
|
||||
@ -197,105 +196,112 @@ The lastest zlib FAQ is at http://www.gzip.org/zlib/zlib_faq.html
|
||||
|
||||
26. Will zlib work on a 64-bit machine?
|
||||
|
||||
It should. It has been tested on 64-bit machines, and has no dependence
|
||||
on any data types being limited to 32-bits in length. If you have any
|
||||
Yes. It has been tested on 64-bit machines, and has no dependence on any
|
||||
data types being limited to 32-bits in length. If you have any
|
||||
difficulties, please provide a complete problem report to zlib@gzip.org
|
||||
|
||||
27. Will zlib decompress data from the PKWare Data Compression Library?
|
||||
|
||||
No. The PKWare DCL uses a completely different compressed data format
|
||||
than does PKZIP and zlib. However, you can look in zlib's contrib/blast
|
||||
No. The PKWare DCL uses a completely different compressed data format than
|
||||
does PKZIP and zlib. However, you can look in zlib's contrib/blast
|
||||
directory for a possible solution to your problem.
|
||||
|
||||
28. Can I access data randomly in a compressed stream?
|
||||
|
||||
No, not without some preparation. If when compressing you periodically
|
||||
use Z_FULL_FLUSH, carefully write all the pending data at those points,
|
||||
and keep an index of those locations, then you can start decompression
|
||||
at those points. You have to be careful to not use Z_FULL_FLUSH too
|
||||
often, since it can significantly degrade compression.
|
||||
No, not without some preparation. If when compressing you periodically use
|
||||
Z_FULL_FLUSH, carefully write all the pending data at those points, and
|
||||
keep an index of those locations, then you can start decompression at those
|
||||
points. You have to be careful to not use Z_FULL_FLUSH too often, since it
|
||||
can significantly degrade compression. Alternatively, you can scan a
|
||||
deflate stream once to generate an index, and then use that index for
|
||||
random access. See examples/zran.c .
|
||||
|
||||
29. Does zlib work on MVS, OS/390, CICS, etc.?
|
||||
|
||||
We don't know for sure. We have heard occasional reports of success on
|
||||
these systems. If you do use it on one of these, please provide us with
|
||||
a report, instructions, and patches that we can reference when we get
|
||||
these questions. Thanks.
|
||||
It has in the past, but we have not heard of any recent evidence. There
|
||||
were working ports of zlib 1.1.4 to MVS, but those links no longer work.
|
||||
If you know of recent, successful applications of zlib on these operating
|
||||
systems, please let us know. Thanks.
|
||||
|
||||
30. Is there some simpler, easier to read version of inflate I can look at
|
||||
to understand the deflate format?
|
||||
30. Is there some simpler, easier to read version of inflate I can look at to
|
||||
understand the deflate format?
|
||||
|
||||
First off, you should read RFC 1951. Second, yes. Look in zlib's
|
||||
First off, you should read RFC 1951. Second, yes. Look in zlib's
|
||||
contrib/puff directory.
|
||||
|
||||
31. Does zlib infringe on any patents?
|
||||
|
||||
As far as we know, no. In fact, that was originally the whole point behind
|
||||
zlib. Look here for some more information:
|
||||
As far as we know, no. In fact, that was originally the whole point behind
|
||||
zlib. Look here for some more information:
|
||||
|
||||
http://www.gzip.org/#faq11
|
||||
|
||||
32. Can zlib work with greater than 4 GB of data?
|
||||
|
||||
Yes. inflate() and deflate() will process any amount of data correctly.
|
||||
Yes. inflate() and deflate() will process any amount of data correctly.
|
||||
Each call of inflate() or deflate() is limited to input and output chunks
|
||||
of the maximum value that can be stored in the compiler's "unsigned int"
|
||||
type, but there is no limit to the number of chunks. Note however that the
|
||||
strm.total_in and strm_total_out counters may be limited to 4 GB. These
|
||||
type, but there is no limit to the number of chunks. Note however that the
|
||||
strm.total_in and strm_total_out counters may be limited to 4 GB. These
|
||||
counters are provided as a convenience and are not used internally by
|
||||
inflate() or deflate(). The application can easily set up its own counters
|
||||
inflate() or deflate(). The application can easily set up its own counters
|
||||
updated after each call of inflate() or deflate() to count beyond 4 GB.
|
||||
compress() and uncompress() may be limited to 4 GB, since they operate in a
|
||||
single call. gzseek() and gztell() may be limited to 4 GB depending on how
|
||||
zlib is compiled. See the zlibCompileFlags() function in zlib.h.
|
||||
single call. gzseek() and gztell() may be limited to 4 GB depending on how
|
||||
zlib is compiled. See the zlibCompileFlags() function in zlib.h.
|
||||
|
||||
The word "may" appears several times above since there is a 4 GB limit
|
||||
only if the compiler's "long" type is 32 bits. If the compiler's "long"
|
||||
type is 64 bits, then the limit is 16 exabytes.
|
||||
The word "may" appears several times above since there is a 4 GB limit only
|
||||
if the compiler's "long" type is 32 bits. If the compiler's "long" type is
|
||||
64 bits, then the limit is 16 exabytes.
|
||||
|
||||
33. Does zlib have any security vulnerabilities?
|
||||
|
||||
The only one that we are aware of is potentially in gzprintf(). If zlib
|
||||
is compiled to use sprintf() or vsprintf(), then there is no protection
|
||||
against a buffer overflow of a 4K string space, other than the caller of
|
||||
gzprintf() assuring that the output will not exceed 4K. On the other
|
||||
hand, if zlib is compiled to use snprintf() or vsnprintf(), which should
|
||||
normally be the case, then there is no vulnerability. The ./configure
|
||||
script will display warnings if an insecure variation of sprintf() will
|
||||
be used by gzprintf(). Also the zlibCompileFlags() function will return
|
||||
information on what variant of sprintf() is used by gzprintf().
|
||||
The only one that we are aware of is potentially in gzprintf(). If zlib is
|
||||
compiled to use sprintf() or vsprintf(), then there is no protection
|
||||
against a buffer overflow of an 8K string space (or other value as set by
|
||||
gzbuffer()), other than the caller of gzprintf() assuring that the output
|
||||
will not exceed 8K. On the other hand, if zlib is compiled to use
|
||||
snprintf() or vsnprintf(), which should normally be the case, then there is
|
||||
no vulnerability. The ./configure script will display warnings if an
|
||||
insecure variation of sprintf() will be used by gzprintf(). Also the
|
||||
zlibCompileFlags() function will return information on what variant of
|
||||
sprintf() is used by gzprintf().
|
||||
|
||||
If you don't have snprintf() or vsnprintf() and would like one, you can
|
||||
find a portable implementation here:
|
||||
|
||||
http://www.ijs.si/software/snprintf/
|
||||
|
||||
Note that you should be using the most recent version of zlib. Versions
|
||||
1.1.3 and before were subject to a double-free vulnerability.
|
||||
Note that you should be using the most recent version of zlib. Versions
|
||||
1.1.3 and before were subject to a double-free vulnerability, and versions
|
||||
1.2.1 and 1.2.2 were subject to an access exception when decompressing
|
||||
invalid compressed data.
|
||||
|
||||
34. Is there a Java version of zlib?
|
||||
|
||||
Probably what you want is to use zlib in Java. zlib is already included
|
||||
as part of the Java SDK in the java.util.zip package. If you really want
|
||||
a version of zlib written in the Java language, look on the zlib home
|
||||
page for links: http://www.zlib.org/
|
||||
page for links: http://zlib.net/ .
|
||||
|
||||
35. I get this or that compiler or source-code scanner warning when I crank it
|
||||
up to maximally-pedantic. Can't you guys write proper code?
|
||||
|
||||
Many years ago, we gave up attempting to avoid warnings on every compiler
|
||||
in the universe. It just got to be a waste of time, and some compilers
|
||||
were downright silly. So now, we simply make sure that the code always
|
||||
works.
|
||||
in the universe. It just got to be a waste of time, and some compilers
|
||||
were downright silly as well as contradicted each other. So now, we simply
|
||||
make sure that the code always works.
|
||||
|
||||
36. Valgrind (or some similar memory access checker) says that deflate is
|
||||
performing a conditional jump that depends on an uninitialized value.
|
||||
Isn't that a bug?
|
||||
|
||||
No. That is intentional for performance reasons, and the output of
|
||||
deflate is not affected. This only started showing up recently since
|
||||
zlib 1.2.x uses malloc() by default for allocations, whereas earlier
|
||||
versions used calloc(), which zeros out the allocated memory.
|
||||
No. That is intentional for performance reasons, and the output of deflate
|
||||
is not affected. This only started showing up recently since zlib 1.2.x
|
||||
uses malloc() by default for allocations, whereas earlier versions used
|
||||
calloc(), which zeros out the allocated memory. Even though the code was
|
||||
correct, versions 1.2.4 and later was changed to not stimulate these
|
||||
checkers.
|
||||
|
||||
37. Will zlib read the (insert any ancient or arcane format here) compressed
|
||||
data format?
|
||||
@ -305,20 +311,21 @@ The lastest zlib FAQ is at http://www.gzip.org/zlib/zlib_faq.html
|
||||
|
||||
38. How can I encrypt/decrypt zip files with zlib?
|
||||
|
||||
zlib doesn't support encryption. The original PKZIP encryption is very weak
|
||||
and can be broken with freely available programs. To get strong encryption,
|
||||
use GnuPG, http://www.gnupg.org/ , which already includes zlib compression.
|
||||
For PKZIP compatible "encryption", look at http://www.info-zip.org/
|
||||
zlib doesn't support encryption. The original PKZIP encryption is very
|
||||
weak and can be broken with freely available programs. To get strong
|
||||
encryption, use GnuPG, http://www.gnupg.org/ , which already includes zlib
|
||||
compression. For PKZIP compatible "encryption", look at
|
||||
http://www.info-zip.org/
|
||||
|
||||
39. What's the difference between the "gzip" and "deflate" HTTP 1.1 encodings?
|
||||
|
||||
"gzip" is the gzip format, and "deflate" is the zlib format. They should
|
||||
probably have called the second one "zlib" instead to avoid confusion
|
||||
with the raw deflate compressed data format. While the HTTP 1.1 RFC 2616
|
||||
"gzip" is the gzip format, and "deflate" is the zlib format. They should
|
||||
probably have called the second one "zlib" instead to avoid confusion with
|
||||
the raw deflate compressed data format. While the HTTP 1.1 RFC 2616
|
||||
correctly points to the zlib specification in RFC 1950 for the "deflate"
|
||||
transfer encoding, there have been reports of servers and browsers that
|
||||
incorrectly produce or expect raw deflate data per the deflate
|
||||
specficiation in RFC 1951, most notably Microsoft. So even though the
|
||||
specficiation in RFC 1951, most notably Microsoft. So even though the
|
||||
"deflate" transfer encoding using the zlib format would be the more
|
||||
efficient approach (and in fact exactly what the zlib format was designed
|
||||
for), using the "gzip" transfer encoding is probably more reliable due to
|
||||
@ -328,12 +335,32 @@ The lastest zlib FAQ is at http://www.gzip.org/zlib/zlib_faq.html
|
||||
|
||||
40. Does zlib support the new "Deflate64" format introduced by PKWare?
|
||||
|
||||
No. PKWare has apparently decided to keep that format proprietary, since
|
||||
they have not documented it as they have previous compression formats.
|
||||
In any case, the compression improvements are so modest compared to other
|
||||
more modern approaches, that it's not worth the effort to implement.
|
||||
No. PKWare has apparently decided to keep that format proprietary, since
|
||||
they have not documented it as they have previous compression formats. In
|
||||
any case, the compression improvements are so modest compared to other more
|
||||
modern approaches, that it's not worth the effort to implement.
|
||||
|
||||
41. Can you please sign these lengthy legal documents and fax them back to us
|
||||
41. I'm having a problem with the zip functions in zlib, can you help?
|
||||
|
||||
There are no zip functions in zlib. You are probably using minizip by
|
||||
Giles Vollant, which is found in the contrib directory of zlib. It is not
|
||||
part of zlib. In fact none of the stuff in contrib is part of zlib. The
|
||||
files in there are not supported by the zlib authors. You need to contact
|
||||
the authors of the respective contribution for help.
|
||||
|
||||
42. The match.asm code in contrib is under the GNU General Public License.
|
||||
Since it's part of zlib, doesn't that mean that all of zlib falls under the
|
||||
GNU GPL?
|
||||
|
||||
No. The files in contrib are not part of zlib. They were contributed by
|
||||
other authors and are provided as a convenience to the user within the zlib
|
||||
distribution. Each item in contrib has its own license.
|
||||
|
||||
43. Is zlib subject to export controls? What is its ECCN?
|
||||
|
||||
zlib is not subject to export controls, and so is classified as EAR99.
|
||||
|
||||
44. Can you please sign these lengthy legal documents and fax them back to us
|
||||
so that we can use your software in our product?
|
||||
|
||||
No. Go away. Shoo.
|
||||
|
@ -4,21 +4,53 @@
|
||||
|
||||
LIB= z
|
||||
SHLIBDIR?= /lib
|
||||
SHLIB_MAJOR= 6
|
||||
MAN= zlib.3
|
||||
|
||||
#CFLAGS+= -DMAX_WBITS=14 -DMAX_MEM_LEVEL=7
|
||||
#CFLAGS+= -g -DDEBUG
|
||||
#CFLAGS+= -Wall -Wwrite-strings -Wpointer-arith -Wconversion \
|
||||
# -Wstrict-prototypes -Wmissing-prototypes
|
||||
#CFLAGS=-O -DMAX_WBITS=14 -DMAX_MEM_LEVEL=7
|
||||
#CFLAGS=-g -DDEBUG
|
||||
#CFLAGS=-O3 -Wall -Wwrite-strings -Wpointer-arith -Wconversion \
|
||||
# -Wstrict-prototypes -Wmissing-prototypes
|
||||
|
||||
CFLAGS+= -DHAS_snprintf -DHAS_vsnprintf
|
||||
CFLAGS+= -DHAS_snprintf -DHAS_vsnprintf -I${.CURDIR}
|
||||
|
||||
WARNS?= 3
|
||||
|
||||
CLEANFILES+= example.o example foo.gz minigzip.o minigzip
|
||||
|
||||
SRCS = adler32.c compress.c crc32.c gzio.c uncompr.c deflate.c trees.c \
|
||||
zutil.c inflate.c inftrees.c inffast.c zopen.c infback.c
|
||||
SRCS+= adler32.c
|
||||
SRCS+= compress.c
|
||||
SRCS+= crc32.c
|
||||
SRCS+= deflate.c
|
||||
SRCS+= gzclose.c
|
||||
SRCS+= gzlib.c
|
||||
SRCS+= gzread.c
|
||||
SRCS+= gzwrite.c
|
||||
SRCS+= infback.c
|
||||
SRCS+= inffast.c
|
||||
SRCS+= inflate.c
|
||||
SRCS+= inftrees.c
|
||||
SRCS+= trees.c
|
||||
SRCS+= uncompr.c
|
||||
SRCS+= zopen.c
|
||||
SRCS+= zutil.c
|
||||
|
||||
.if ${MACHINE_ARCH} == "i386" && ${MACHINE_CPU:M*i686*}
|
||||
.PATH: ${.CURDIR}/contrib/asm686
|
||||
SRCS+= match.S
|
||||
CFLAGS+= -DASMV -DNO_UNDERLINE
|
||||
.endif
|
||||
|
||||
.if ${MACHINE_ARCH} == "amd64"
|
||||
.PATH: ${.CURDIR}/contrib/gcc_gvmat64
|
||||
SRCS+= gvmat64.S
|
||||
CFLAGS+= -DASMV -DNO_UNDERLINE
|
||||
.endif
|
||||
|
||||
VERSION_DEF= ${.CURDIR}/Versions.def
|
||||
SYMBOL_MAPS= ${.CURDIR}/Symbol.map
|
||||
CFLAGS+= -DSYMBOL_VERSIONING
|
||||
|
||||
INCS= zconf.h zlib.h
|
||||
|
||||
minigzip: all minigzip.o
|
||||
|
@ -1,56 +1,51 @@
|
||||
ZLIB DATA COMPRESSION LIBRARY
|
||||
|
||||
zlib 1.2.3 is a general purpose data compression library. All the code is
|
||||
zlib 1.2.4 is a general purpose data compression library. All the code is
|
||||
thread safe. The data format used by the zlib library is described by RFCs
|
||||
(Request for Comments) 1950 to 1952 in the files
|
||||
http://www.ietf.org/rfc/rfc1950.txt (zlib format), rfc1951.txt (deflate format)
|
||||
and rfc1952.txt (gzip format). These documents are also available in other
|
||||
formats from ftp://ftp.uu.net/graphics/png/documents/zlib/zdoc-index.html
|
||||
and rfc1952.txt (gzip format).
|
||||
|
||||
All functions of the compression library are documented in the file zlib.h
|
||||
(volunteer to write man pages welcome, contact zlib@gzip.org). A usage example
|
||||
(volunteer to write man pages welcome, contact zlib@gzip.org). A usage example
|
||||
of the library is given in the file example.c which also tests that the library
|
||||
is working correctly. Another example is given in the file minigzip.c. The
|
||||
is working correctly. Another example is given in the file minigzip.c. The
|
||||
compression library itself is composed of all source files except example.c and
|
||||
minigzip.c.
|
||||
|
||||
To compile all files and run the test program, follow the instructions given at
|
||||
the top of Makefile. In short "make test; make install" should work for most
|
||||
machines. For Unix: "./configure; make test; make install". For MSDOS, use one
|
||||
of the special makefiles such as Makefile.msc. For VMS, use make_vms.com.
|
||||
the top of Makefile.in. In short "./configure; make test", and if that goes
|
||||
well, "make install" should work for most flavors of Unix. For Windows, use one
|
||||
of the special makefiles in win32/ or projects/ . For VMS, use make_vms.com.
|
||||
|
||||
Questions about zlib should be sent to <zlib@gzip.org>, or to Gilles Vollant
|
||||
<info@winimage.com> for the Windows DLL version. The zlib home page is
|
||||
http://www.zlib.org or http://www.gzip.org/zlib/ Before reporting a problem,
|
||||
please check this site to verify that you have the latest version of zlib;
|
||||
otherwise get the latest version and check whether the problem still exists or
|
||||
not.
|
||||
<info@winimage.com> for the Windows DLL version. The zlib home page is
|
||||
http://zlib.net/ . Before reporting a problem, please check this site to
|
||||
verify that you have the latest version of zlib; otherwise get the latest
|
||||
version and check whether the problem still exists or not.
|
||||
|
||||
PLEASE read the zlib FAQ http://www.gzip.org/zlib/zlib_faq.html before asking
|
||||
for help.
|
||||
PLEASE read the zlib FAQ http://zlib.net/zlib_faq.html before asking for help.
|
||||
|
||||
Mark Nelson <markn@ieee.org> wrote an article about zlib for the Jan. 1997
|
||||
issue of Dr. Dobb's Journal; a copy of the article is available in
|
||||
http://dogma.net/markn/articles/zlibtool/zlibtool.htm
|
||||
Mark Nelson <markn@ieee.org> wrote an article about zlib for the Jan. 1997
|
||||
issue of Dr. Dobb's Journal; a copy of the article is available at
|
||||
http://marknelson.us/1997/01/01/zlib-engine/ .
|
||||
|
||||
The changes made in version 1.2.3 are documented in the file ChangeLog.
|
||||
The changes made in version 1.2.4 are documented in the file ChangeLog.
|
||||
|
||||
Unsupported third party contributions are provided in directory "contrib".
|
||||
Unsupported third party contributions are provided in directory contrib/ .
|
||||
|
||||
A Java implementation of zlib is available in the Java Development Kit
|
||||
http://java.sun.com/j2se/1.4.2/docs/api/java/util/zip/package-summary.html
|
||||
See the zlib home page http://www.zlib.org for details.
|
||||
zlib is available in Java using the java.util.zip package, documented at
|
||||
http://java.sun.com/developer/technicalArticles/Programming/compression/ .
|
||||
|
||||
A Perl interface to zlib written by Paul Marquess <pmqs@cpan.org> is in the
|
||||
CPAN (Comprehensive Perl Archive Network) sites
|
||||
http://www.cpan.org/modules/by-module/Compress/
|
||||
A Perl interface to zlib written by Paul Marquess <pmqs@cpan.org> is available
|
||||
at CPAN (Comprehensive Perl Archive Network) sites, including
|
||||
http://search.cpan.org/~pmqs/IO-Compress-Zlib/ .
|
||||
|
||||
A Python interface to zlib written by A.M. Kuchling <amk@amk.ca> is
|
||||
available in Python 1.5 and later versions, see
|
||||
http://www.python.org/doc/lib/module-zlib.html
|
||||
http://www.python.org/doc/lib/module-zlib.html .
|
||||
|
||||
A zlib binding for TCL written by Andreas Kupries <a.kupries@westend.com> is
|
||||
availlable at http://www.oche.de/~akupries/soft/trf/trf_zip.html
|
||||
zlib is built into tcl: http://wiki.tcl.tk/4610 .
|
||||
|
||||
An experimental package to read and write files in .zip format, written on top
|
||||
of zlib by Gilles Vollant <info@winimage.com>, is available in the
|
||||
@ -74,25 +69,21 @@ Notes for some targets:
|
||||
- zlib doesn't work on HP-UX 9.05 with some versions of /bin/cc. It works with
|
||||
other compilers. Use "make test" to check your compiler.
|
||||
|
||||
- gzdopen is not supported on RISCOS, BEOS and by some Mac compilers.
|
||||
- gzdopen is not supported on RISCOS or BEOS.
|
||||
|
||||
- For PalmOs, see http://palmzlib.sourceforge.net/
|
||||
|
||||
- When building a shared, i.e. dynamic library on Mac OS X, the library must be
|
||||
installed before testing (do "make install" before "make test"), since the
|
||||
library location is specified in the library.
|
||||
|
||||
|
||||
Acknowledgments:
|
||||
|
||||
The deflate format used by zlib was defined by Phil Katz. The deflate
|
||||
and zlib specifications were written by L. Peter Deutsch. Thanks to all the
|
||||
people who reported problems and suggested various improvements in zlib;
|
||||
they are too numerous to cite here.
|
||||
The deflate format used by zlib was defined by Phil Katz. The deflate and
|
||||
zlib specifications were written by L. Peter Deutsch. Thanks to all the
|
||||
people who reported problems and suggested various improvements in zlib; they
|
||||
are too numerous to cite here.
|
||||
|
||||
Copyright notice:
|
||||
|
||||
(C) 1995-2004 Jean-loup Gailly and Mark Adler
|
||||
(C) 1995-2010 Jean-loup Gailly and Mark Adler
|
||||
|
||||
This software is provided 'as-is', without any express or implied
|
||||
warranty. In no event will the authors be held liable for any damages
|
||||
@ -113,13 +104,11 @@ Copyright notice:
|
||||
Jean-loup Gailly Mark Adler
|
||||
jloup@gzip.org madler@alumni.caltech.edu
|
||||
|
||||
If you use the zlib library in a product, we would appreciate *not*
|
||||
receiving lengthy legal documents to sign. The sources are provided
|
||||
for free but without warranty of any kind. The library has been
|
||||
entirely written by Jean-loup Gailly and Mark Adler; it does not
|
||||
include third-party code.
|
||||
If you use the zlib library in a product, we would appreciate *not* receiving
|
||||
lengthy legal documents to sign. The sources are provided for free but without
|
||||
warranty of any kind. The library has been entirely written by Jean-loup
|
||||
Gailly and Mark Adler; it does not include third-party code.
|
||||
|
||||
If you redistribute modified sources, we would appreciate that you include
|
||||
in the file ChangeLog history information documenting your changes. Please
|
||||
read the FAQ for more information on the distribution of modified source
|
||||
versions.
|
||||
If you redistribute modified sources, we would appreciate that you include in
|
||||
the file ChangeLog history information documenting your changes. Please read
|
||||
the FAQ for more information on the distribution of modified source versions.
|
||||
|
96
lib/libz/Symbol.map
Normal file
96
lib/libz/Symbol.map
Normal file
@ -0,0 +1,96 @@
|
||||
/*
|
||||
* $FreeBSD$
|
||||
*/
|
||||
|
||||
ZLIB_1.2.4.0 {
|
||||
adler32;
|
||||
adler32_combine64;
|
||||
compress;
|
||||
compress2;
|
||||
compressBound;
|
||||
crc32;
|
||||
crc32_combine64;
|
||||
deflate;
|
||||
deflateBound;
|
||||
deflateCopy;
|
||||
deflateEnd;
|
||||
deflateInit2_;
|
||||
deflateInit_;
|
||||
deflateParams;
|
||||
deflatePrime;
|
||||
deflateReset;
|
||||
deflateSetDictionary;
|
||||
deflateSetHeader;
|
||||
deflateTune;
|
||||
get_crc_table;
|
||||
gzbuffer;
|
||||
gzclearerr;
|
||||
gzclose;
|
||||
gzclose_r;
|
||||
gzclose_w;
|
||||
gzdirect;
|
||||
gzdopen;
|
||||
gzeof;
|
||||
gzerror;
|
||||
gzflush;
|
||||
gzgetc;
|
||||
gzgets;
|
||||
gzoffset64;
|
||||
gzopen64;
|
||||
gzprintf;
|
||||
gzputc;
|
||||
gzputs;
|
||||
gzread;
|
||||
gzrewind;
|
||||
gzseek64;
|
||||
gzsetparams;
|
||||
gztell64;
|
||||
gzungetc;
|
||||
gzwrite;
|
||||
inflate;
|
||||
inflateBack;
|
||||
inflateBackEnd;
|
||||
inflateBackInit_;
|
||||
inflateCopy;
|
||||
inflateEnd;
|
||||
inflateGetHeader;
|
||||
inflateInit2_;
|
||||
inflateInit_;
|
||||
inflateMark;
|
||||
inflatePrime;
|
||||
inflateReset;
|
||||
inflateReset2;
|
||||
inflateSetDictionary;
|
||||
inflateSync;
|
||||
inflateSyncPoint;
|
||||
inflateUndermine;
|
||||
uncompress;
|
||||
zError;
|
||||
zlibCompileFlags;
|
||||
zlibVersion;
|
||||
};
|
||||
|
||||
FBSD_1.2 {
|
||||
zopen;
|
||||
};
|
||||
|
||||
ZLIBprivate_1.0 {
|
||||
_tr_align;
|
||||
_tr_flush_block;
|
||||
_tr_init;
|
||||
_tr_stored_block;
|
||||
_tr_tally;
|
||||
adler32_combine;
|
||||
crc32_combine;
|
||||
gz_error;
|
||||
gzoffset;
|
||||
gzopen;
|
||||
gzseek;
|
||||
gztell;
|
||||
inflate_fast;
|
||||
inflate_table;
|
||||
longest_match;
|
||||
match_init;
|
||||
zcalloc;
|
||||
zcfree;
|
||||
};
|
11
lib/libz/Versions.def
Normal file
11
lib/libz/Versions.def
Normal file
@ -0,0 +1,11 @@
|
||||
# $FreeBSD$
|
||||
|
||||
ZLIB_1.2.4.0 {
|
||||
};
|
||||
|
||||
FBSD_1.2 {
|
||||
} ZLIB_1.2.4.0;
|
||||
|
||||
ZLIBprivate_1.0 {
|
||||
} ZLIB_1.2.4.0;
|
||||
|
@ -1,12 +1,15 @@
|
||||
/* adler32.c -- compute the Adler-32 checksum of a data stream
|
||||
* Copyright (C) 1995-2004 Mark Adler
|
||||
* Copyright (C) 1995-2007 Mark Adler
|
||||
* For conditions of distribution and use, see copyright notice in zlib.h
|
||||
*/
|
||||
|
||||
/* @(#) $Id$ */
|
||||
|
||||
#define ZLIB_INTERNAL
|
||||
#include "zlib.h"
|
||||
#include "zutil.h"
|
||||
|
||||
#define local static
|
||||
|
||||
local uLong adler32_combine_(uLong adler1, uLong adler2, z_off64_t len2);
|
||||
|
||||
#define BASE 65521UL /* largest prime smaller than 65536 */
|
||||
#define NMAX 5552
|
||||
@ -125,10 +128,10 @@ uLong ZEXPORT adler32(adler, buf, len)
|
||||
}
|
||||
|
||||
/* ========================================================================= */
|
||||
uLong ZEXPORT adler32_combine(adler1, adler2, len2)
|
||||
local uLong adler32_combine_(adler1, adler2, len2)
|
||||
uLong adler1;
|
||||
uLong adler2;
|
||||
z_off_t len2;
|
||||
z_off64_t len2;
|
||||
{
|
||||
unsigned long sum1;
|
||||
unsigned long sum2;
|
||||
@ -141,9 +144,26 @@ uLong ZEXPORT adler32_combine(adler1, adler2, len2)
|
||||
MOD(sum2);
|
||||
sum1 += (adler2 & 0xffff) + BASE - 1;
|
||||
sum2 += ((adler1 >> 16) & 0xffff) + ((adler2 >> 16) & 0xffff) + BASE - rem;
|
||||
if (sum1 > BASE) sum1 -= BASE;
|
||||
if (sum1 > BASE) sum1 -= BASE;
|
||||
if (sum2 > (BASE << 1)) sum2 -= (BASE << 1);
|
||||
if (sum2 > BASE) sum2 -= BASE;
|
||||
if (sum1 >= BASE) sum1 -= BASE;
|
||||
if (sum1 >= BASE) sum1 -= BASE;
|
||||
if (sum2 >= (BASE << 1)) sum2 -= (BASE << 1);
|
||||
if (sum2 >= BASE) sum2 -= BASE;
|
||||
return sum1 | (sum2 << 16);
|
||||
}
|
||||
|
||||
/* ========================================================================= */
|
||||
uLong ZEXPORT adler32_combine(adler1, adler2, len2)
|
||||
uLong adler1;
|
||||
uLong adler2;
|
||||
z_off_t len2;
|
||||
{
|
||||
return adler32_combine_(adler1, adler2, len2);
|
||||
}
|
||||
|
||||
uLong ZEXPORT adler32_combine64(adler1, adler2, len2)
|
||||
uLong adler1;
|
||||
uLong adler2;
|
||||
z_off64_t len2;
|
||||
{
|
||||
return adler32_combine_(adler1, adler2, len2);
|
||||
}
|
||||
|
@ -1,5 +1,5 @@
|
||||
/* compress.c -- compress a memory buffer
|
||||
* Copyright (C) 1995-2003 Jean-loup Gailly.
|
||||
* Copyright (C) 1995-2005 Jean-loup Gailly.
|
||||
* For conditions of distribution and use, see copyright notice in zlib.h
|
||||
*/
|
||||
|
||||
@ -75,5 +75,6 @@ int ZEXPORT compress (dest, destLen, source, sourceLen)
|
||||
uLong ZEXPORT compressBound (sourceLen)
|
||||
uLong sourceLen;
|
||||
{
|
||||
return sourceLen + (sourceLen >> 12) + (sourceLen >> 14) + 11;
|
||||
return sourceLen + (sourceLen >> 12) + (sourceLen >> 14) +
|
||||
(sourceLen >> 25) + 13;
|
||||
}
|
||||
|
77
lib/libz/contrib/README.contrib
Normal file
77
lib/libz/contrib/README.contrib
Normal file
@ -0,0 +1,77 @@
|
||||
All files under this contrib directory are UNSUPPORTED. There were
|
||||
provided by users of zlib and were not tested by the authors of zlib.
|
||||
Use at your own risk. Please contact the authors of the contributions
|
||||
for help about these, not the zlib authors. Thanks.
|
||||
|
||||
|
||||
ada/ by Dmitriy Anisimkov <anisimkov@yahoo.com>
|
||||
Support for Ada
|
||||
See http://zlib-ada.sourceforge.net/
|
||||
|
||||
amd64/ by Mikhail Teterin <mi@ALDAN.algebra.com>
|
||||
asm code for AMD64
|
||||
See patch at http://www.freebsd.org/cgi/query-pr.cgi?pr=bin/96393
|
||||
|
||||
asm686/ by Brian Raiter <breadbox@muppetlabs.com>
|
||||
asm code for Pentium and PPro/PII, using the AT&T (GNU as) syntax
|
||||
See http://www.muppetlabs.com/~breadbox/software/assembly.html
|
||||
|
||||
blast/ by Mark Adler <madler@alumni.caltech.edu>
|
||||
Decompressor for output of PKWare Data Compression Library (DCL)
|
||||
|
||||
delphi/ by Cosmin Truta <cosmint@cs.ubbcluj.ro>
|
||||
Support for Delphi and C++ Builder
|
||||
|
||||
dotzlib/ by Henrik Ravn <henrik@ravn.com>
|
||||
Support for Microsoft .Net and Visual C++ .Net
|
||||
|
||||
gcc_gvmat64/by Gilles Vollant <info@winimage.com>
|
||||
GCC Version of x86 64-bit (AMD64 and Intel EM64t) code for x64
|
||||
assembler to replace longest_match() and inflate_fast()
|
||||
|
||||
infback9/ by Mark Adler <madler@alumni.caltech.edu>
|
||||
Unsupported diffs to infback to decode the deflate64 format
|
||||
|
||||
inflate86/ by Chris Anderson <christop@charm.net>
|
||||
Tuned x86 gcc asm code to replace inflate_fast()
|
||||
|
||||
iostream/ by Kevin Ruland <kevin@rodin.wustl.edu>
|
||||
A C++ I/O streams interface to the zlib gz* functions
|
||||
|
||||
iostream2/ by Tyge Løvset <Tyge.Lovset@cmr.no>
|
||||
Another C++ I/O streams interface
|
||||
|
||||
iostream3/ by Ludwig Schwardt <schwardt@sun.ac.za>
|
||||
and Kevin Ruland <kevin@rodin.wustl.edu>
|
||||
Yet another C++ I/O streams interface
|
||||
|
||||
masmx64/ by Gilles Vollant <info@winimage.com>
|
||||
x86 64-bit (AMD64 and Intel EM64t) code for x64 assembler to
|
||||
replace longest_match() and inflate_fast(), also masm x86
|
||||
64-bits translation of Chris Anderson inflate_fast()
|
||||
|
||||
masmx86/ by Gilles Vollant <info@winimage.com>
|
||||
x86 asm code to replace longest_match() and inflate_fast(),
|
||||
for Visual C++ and MASM (32 bits).
|
||||
Based on Brian Raiter (asm686) and Chris Anderson (inflate86)
|
||||
|
||||
minizip/ by Gilles Vollant <info@winimage.com>
|
||||
Mini zip and unzip based on zlib
|
||||
Includes Zip64 support by Mathias Svensson <mathias@result42.com>
|
||||
See http://www.winimage.com/zLibDll/unzip.html
|
||||
|
||||
pascal/ by Bob Dellaca <bobdl@xtra.co.nz> et al.
|
||||
Support for Pascal
|
||||
|
||||
puff/ by Mark Adler <madler@alumni.caltech.edu>
|
||||
Small, low memory usage inflate. Also serves to provide an
|
||||
unambiguous description of the deflate format.
|
||||
|
||||
testzlib/ by Gilles Vollant <info@winimage.com>
|
||||
Example of the use of zlib
|
||||
|
||||
untgz/ by Pedro A. Aranda Gutierrez <paag@tid.es>
|
||||
A very simple tar.gz file extractor using zlib
|
||||
|
||||
vstudio/ by Gilles Vollant <info@winimage.com>
|
||||
Building a minizip-enhanced zlib with Microsoft Visual Studio
|
51
lib/libz/contrib/asm686/README.686
Normal file
51
lib/libz/contrib/asm686/README.686
Normal file
@ -0,0 +1,51 @@
|
||||
This is a patched version of zlib, modified to use
|
||||
Pentium-Pro-optimized assembly code in the deflation algorithm. The
|
||||
files changed/added by this patch are:
|
||||
|
||||
README.686
|
||||
match.S
|
||||
|
||||
The speedup that this patch provides varies, depending on whether the
|
||||
compiler used to build the original version of zlib falls afoul of the
|
||||
PPro's speed traps. My own tests show a speedup of around 10-20% at
|
||||
the default compression level, and 20-30% using -9, against a version
|
||||
compiled using gcc 2.7.2.3. Your mileage may vary.
|
||||
|
||||
Note that this code has been tailored for the PPro/PII in particular,
|
||||
and will not perform particuarly well on a Pentium.
|
||||
|
||||
If you are using an assembler other than GNU as, you will have to
|
||||
translate match.S to use your assembler's syntax. (Have fun.)
|
||||
|
||||
Brian Raiter
|
||||
breadbox@muppetlabs.com
|
||||
April, 1998
|
||||
|
||||
|
||||
Added for zlib 1.1.3:
|
||||
|
||||
The patches come from
|
||||
http://www.muppetlabs.com/~breadbox/software/assembly.html
|
||||
|
||||
To compile zlib with this asm file, copy match.S to the zlib directory
|
||||
then do:
|
||||
|
||||
CFLAGS="-O3 -DASMV" ./configure
|
||||
make OBJA=match.o
|
||||
|
||||
|
||||
Update:
|
||||
|
||||
I've been ignoring these assembly routines for years, believing that
|
||||
gcc's generated code had caught up with it sometime around gcc 2.95
|
||||
and the major rearchitecting of the Pentium 4. However, I recently
|
||||
learned that, despite what I believed, this code still has some life
|
||||
in it. On the Pentium 4 and AMD64 chips, it continues to run about 8%
|
||||
faster than the code produced by gcc 4.1.
|
||||
|
||||
In acknowledgement of its continuing usefulness, I've altered the
|
||||
license to match that of the rest of zlib. Share and Enjoy!
|
||||
|
||||
Brian Raiter
|
||||
breadbox@muppetlabs.com
|
||||
April, 2007
|
343
lib/libz/contrib/asm686/match.S
Normal file
343
lib/libz/contrib/asm686/match.S
Normal file
@ -0,0 +1,343 @@
|
||||
/* match.S -- x86 assembly version of the zlib longest_match() function.
|
||||
* Optimized for the Intel 686 chips (PPro and later).
|
||||
*
|
||||
* Copyright (C) 1998, 2007 Brian Raiter <breadbox@muppetlabs.com>
|
||||
*
|
||||
* This software is provided 'as-is', without any express or implied
|
||||
* warranty. In no event will the author be held liable for any damages
|
||||
* arising from the use of this software.
|
||||
*
|
||||
* Permission is granted to anyone to use this software for any purpose,
|
||||
* including commercial applications, and to alter it and redistribute it
|
||||
* freely, subject to the following restrictions:
|
||||
*
|
||||
* 1. The origin of this software must not be misrepresented; you must not
|
||||
* claim that you wrote the original software. If you use this software
|
||||
* in a product, an acknowledgment in the product documentation would be
|
||||
* appreciated but is not required.
|
||||
* 2. Altered source versions must be plainly marked as such, and must not be
|
||||
* misrepresented as being the original software.
|
||||
* 3. This notice may not be removed or altered from any source distribution.
|
||||
*/
|
||||
|
||||
#ifndef NO_UNDERLINE
|
||||
#define match_init _match_init
|
||||
#define longest_match _longest_match
|
||||
#endif
|
||||
|
||||
#define MAX_MATCH (258)
|
||||
#define MIN_MATCH (3)
|
||||
#define MIN_LOOKAHEAD (MAX_MATCH + MIN_MATCH + 1)
|
||||
#define MAX_MATCH_8 ((MAX_MATCH + 7) & ~7)
|
||||
|
||||
/* stack frame offsets */
|
||||
|
||||
#define chainlenwmask 0 /* high word: current chain len */
|
||||
/* low word: s->wmask */
|
||||
#define window 4 /* local copy of s->window */
|
||||
#define windowbestlen 8 /* s->window + bestlen */
|
||||
#define scanstart 16 /* first two bytes of string */
|
||||
#define scanend 12 /* last two bytes of string */
|
||||
#define scanalign 20 /* dword-misalignment of string */
|
||||
#define nicematch 24 /* a good enough match size */
|
||||
#define bestlen 28 /* size of best match so far */
|
||||
#define scan 32 /* ptr to string wanting match */
|
||||
|
||||
#define LocalVarsSize (36)
|
||||
/* saved ebx 36 */
|
||||
/* saved edi 40 */
|
||||
/* saved esi 44 */
|
||||
/* saved ebp 48 */
|
||||
/* return address 52 */
|
||||
#define deflatestate 56 /* the function arguments */
|
||||
#define curmatch 60
|
||||
|
||||
/* All the +zlib1222add offsets are due to the addition of fields
|
||||
* in zlib in the deflate_state structure since the asm code was first written
|
||||
* (if you compile with zlib 1.0.4 or older, use "zlib1222add equ (-4)").
|
||||
* (if you compile with zlib between 1.0.5 and 1.2.2.1, use "zlib1222add equ 0").
|
||||
* if you compile with zlib 1.2.2.2 or later , use "zlib1222add equ 8").
|
||||
*/
|
||||
|
||||
#define zlib1222add (8)
|
||||
|
||||
#define dsWSize (36+zlib1222add)
|
||||
#define dsWMask (44+zlib1222add)
|
||||
#define dsWindow (48+zlib1222add)
|
||||
#define dsPrev (56+zlib1222add)
|
||||
#define dsMatchLen (88+zlib1222add)
|
||||
#define dsPrevMatch (92+zlib1222add)
|
||||
#define dsStrStart (100+zlib1222add)
|
||||
#define dsMatchStart (104+zlib1222add)
|
||||
#define dsLookahead (108+zlib1222add)
|
||||
#define dsPrevLen (112+zlib1222add)
|
||||
#define dsMaxChainLen (116+zlib1222add)
|
||||
#define dsGoodMatch (132+zlib1222add)
|
||||
#define dsNiceMatch (136+zlib1222add)
|
||||
|
||||
|
||||
.file "match.S"
|
||||
|
||||
.globl match_init, longest_match
|
||||
|
||||
.text
|
||||
|
||||
/* uInt longest_match(deflate_state *deflatestate, IPos curmatch) */
|
||||
|
||||
longest_match:
|
||||
|
||||
/* Save registers that the compiler may be using, and adjust %esp to */
|
||||
/* make room for our stack frame. */
|
||||
|
||||
pushl %ebp
|
||||
pushl %edi
|
||||
pushl %esi
|
||||
pushl %ebx
|
||||
subl $LocalVarsSize, %esp
|
||||
|
||||
/* Retrieve the function arguments. %ecx will hold cur_match */
|
||||
/* throughout the entire function. %edx will hold the pointer to the */
|
||||
/* deflate_state structure during the function's setup (before */
|
||||
/* entering the main loop). */
|
||||
|
||||
movl deflatestate(%esp), %edx
|
||||
movl curmatch(%esp), %ecx
|
||||
|
||||
/* uInt wmask = s->w_mask; */
|
||||
/* unsigned chain_length = s->max_chain_length; */
|
||||
/* if (s->prev_length >= s->good_match) { */
|
||||
/* chain_length >>= 2; */
|
||||
/* } */
|
||||
|
||||
movl dsPrevLen(%edx), %eax
|
||||
movl dsGoodMatch(%edx), %ebx
|
||||
cmpl %ebx, %eax
|
||||
movl dsWMask(%edx), %eax
|
||||
movl dsMaxChainLen(%edx), %ebx
|
||||
jl LastMatchGood
|
||||
shrl $2, %ebx
|
||||
LastMatchGood:
|
||||
|
||||
/* chainlen is decremented once beforehand so that the function can */
|
||||
/* use the sign flag instead of the zero flag for the exit test. */
|
||||
/* It is then shifted into the high word, to make room for the wmask */
|
||||
/* value, which it will always accompany. */
|
||||
|
||||
decl %ebx
|
||||
shll $16, %ebx
|
||||
orl %eax, %ebx
|
||||
movl %ebx, chainlenwmask(%esp)
|
||||
|
||||
/* if ((uInt)nice_match > s->lookahead) nice_match = s->lookahead; */
|
||||
|
||||
movl dsNiceMatch(%edx), %eax
|
||||
movl dsLookahead(%edx), %ebx
|
||||
cmpl %eax, %ebx
|
||||
jl LookaheadLess
|
||||
movl %eax, %ebx
|
||||
LookaheadLess: movl %ebx, nicematch(%esp)
|
||||
|
||||
/* register Bytef *scan = s->window + s->strstart; */
|
||||
|
||||
movl dsWindow(%edx), %esi
|
||||
movl %esi, window(%esp)
|
||||
movl dsStrStart(%edx), %ebp
|
||||
lea (%esi,%ebp), %edi
|
||||
movl %edi, scan(%esp)
|
||||
|
||||
/* Determine how many bytes the scan ptr is off from being */
|
||||
/* dword-aligned. */
|
||||
|
||||
movl %edi, %eax
|
||||
negl %eax
|
||||
andl $3, %eax
|
||||
movl %eax, scanalign(%esp)
|
||||
|
||||
/* IPos limit = s->strstart > (IPos)MAX_DIST(s) ? */
|
||||
/* s->strstart - (IPos)MAX_DIST(s) : NIL; */
|
||||
|
||||
movl dsWSize(%edx), %eax
|
||||
subl $MIN_LOOKAHEAD, %eax
|
||||
subl %eax, %ebp
|
||||
jg LimitPositive
|
||||
xorl %ebp, %ebp
|
||||
LimitPositive:
|
||||
|
||||
/* int best_len = s->prev_length; */
|
||||
|
||||
movl dsPrevLen(%edx), %eax
|
||||
movl %eax, bestlen(%esp)
|
||||
|
||||
/* Store the sum of s->window + best_len in %esi locally, and in %esi. */
|
||||
|
||||
addl %eax, %esi
|
||||
movl %esi, windowbestlen(%esp)
|
||||
|
||||
/* register ush scan_start = *(ushf*)scan; */
|
||||
/* register ush scan_end = *(ushf*)(scan+best_len-1); */
|
||||
/* Posf *prev = s->prev; */
|
||||
|
||||
movzwl (%edi), %ebx
|
||||
movl %ebx, scanstart(%esp)
|
||||
movzwl -1(%edi,%eax), %ebx
|
||||
movl %ebx, scanend(%esp)
|
||||
movl dsPrev(%edx), %edi
|
||||
|
||||
/* Jump into the main loop. */
|
||||
|
||||
movl chainlenwmask(%esp), %edx
|
||||
jmp LoopEntry
|
||||
|
||||
.balign 16
|
||||
|
||||
/* do {
|
||||
* match = s->window + cur_match;
|
||||
* if (*(ushf*)(match+best_len-1) != scan_end ||
|
||||
* *(ushf*)match != scan_start) continue;
|
||||
* [...]
|
||||
* } while ((cur_match = prev[cur_match & wmask]) > limit
|
||||
* && --chain_length != 0);
|
||||
*
|
||||
* Here is the inner loop of the function. The function will spend the
|
||||
* majority of its time in this loop, and majority of that time will
|
||||
* be spent in the first ten instructions.
|
||||
*
|
||||
* Within this loop:
|
||||
* %ebx = scanend
|
||||
* %ecx = curmatch
|
||||
* %edx = chainlenwmask - i.e., ((chainlen << 16) | wmask)
|
||||
* %esi = windowbestlen - i.e., (window + bestlen)
|
||||
* %edi = prev
|
||||
* %ebp = limit
|
||||
*/
|
||||
LookupLoop:
|
||||
andl %edx, %ecx
|
||||
movzwl (%edi,%ecx,2), %ecx
|
||||
cmpl %ebp, %ecx
|
||||
jbe LeaveNow
|
||||
subl $0x00010000, %edx
|
||||
js LeaveNow
|
||||
LoopEntry: movzwl -1(%esi,%ecx), %eax
|
||||
cmpl %ebx, %eax
|
||||
jnz LookupLoop
|
||||
movl window(%esp), %eax
|
||||
movzwl (%eax,%ecx), %eax
|
||||
cmpl scanstart(%esp), %eax
|
||||
jnz LookupLoop
|
||||
|
||||
/* Store the current value of chainlen. */
|
||||
|
||||
movl %edx, chainlenwmask(%esp)
|
||||
|
||||
/* Point %edi to the string under scrutiny, and %esi to the string we */
|
||||
/* are hoping to match it up with. In actuality, %esi and %edi are */
|
||||
/* both pointed (MAX_MATCH_8 - scanalign) bytes ahead, and %edx is */
|
||||
/* initialized to -(MAX_MATCH_8 - scanalign). */
|
||||
|
||||
movl window(%esp), %esi
|
||||
movl scan(%esp), %edi
|
||||
addl %ecx, %esi
|
||||
movl scanalign(%esp), %eax
|
||||
movl $(-MAX_MATCH_8), %edx
|
||||
lea MAX_MATCH_8(%edi,%eax), %edi
|
||||
lea MAX_MATCH_8(%esi,%eax), %esi
|
||||
|
||||
/* Test the strings for equality, 8 bytes at a time. At the end,
|
||||
* adjust %edx so that it is offset to the exact byte that mismatched.
|
||||
*
|
||||
* We already know at this point that the first three bytes of the
|
||||
* strings match each other, and they can be safely passed over before
|
||||
* starting the compare loop. So what this code does is skip over 0-3
|
||||
* bytes, as much as necessary in order to dword-align the %edi
|
||||
* pointer. (%esi will still be misaligned three times out of four.)
|
||||
*
|
||||
* It should be confessed that this loop usually does not represent
|
||||
* much of the total running time. Replacing it with a more
|
||||
* straightforward "rep cmpsb" would not drastically degrade
|
||||
* performance.
|
||||
*/
|
||||
LoopCmps:
|
||||
movl (%esi,%edx), %eax
|
||||
xorl (%edi,%edx), %eax
|
||||
jnz LeaveLoopCmps
|
||||
movl 4(%esi,%edx), %eax
|
||||
xorl 4(%edi,%edx), %eax
|
||||
jnz LeaveLoopCmps4
|
||||
addl $8, %edx
|
||||
jnz LoopCmps
|
||||
jmp LenMaximum
|
||||
LeaveLoopCmps4: addl $4, %edx
|
||||
LeaveLoopCmps: testl $0x0000FFFF, %eax
|
||||
jnz LenLower
|
||||
addl $2, %edx
|
||||
shrl $16, %eax
|
||||
LenLower: subb $1, %al
|
||||
adcl $0, %edx
|
||||
|
||||
/* Calculate the length of the match. If it is longer than MAX_MATCH, */
|
||||
/* then automatically accept it as the best possible match and leave. */
|
||||
|
||||
lea (%edi,%edx), %eax
|
||||
movl scan(%esp), %edi
|
||||
subl %edi, %eax
|
||||
cmpl $MAX_MATCH, %eax
|
||||
jge LenMaximum
|
||||
|
||||
/* If the length of the match is not longer than the best match we */
|
||||
/* have so far, then forget it and return to the lookup loop. */
|
||||
|
||||
movl deflatestate(%esp), %edx
|
||||
movl bestlen(%esp), %ebx
|
||||
cmpl %ebx, %eax
|
||||
jg LongerMatch
|
||||
movl windowbestlen(%esp), %esi
|
||||
movl dsPrev(%edx), %edi
|
||||
movl scanend(%esp), %ebx
|
||||
movl chainlenwmask(%esp), %edx
|
||||
jmp LookupLoop
|
||||
|
||||
/* s->match_start = cur_match; */
|
||||
/* best_len = len; */
|
||||
/* if (len >= nice_match) break; */
|
||||
/* scan_end = *(ushf*)(scan+best_len-1); */
|
||||
|
||||
LongerMatch: movl nicematch(%esp), %ebx
|
||||
movl %eax, bestlen(%esp)
|
||||
movl %ecx, dsMatchStart(%edx)
|
||||
cmpl %ebx, %eax
|
||||
jge LeaveNow
|
||||
movl window(%esp), %esi
|
||||
addl %eax, %esi
|
||||
movl %esi, windowbestlen(%esp)
|
||||
movzwl -1(%edi,%eax), %ebx
|
||||
movl dsPrev(%edx), %edi
|
||||
movl %ebx, scanend(%esp)
|
||||
movl chainlenwmask(%esp), %edx
|
||||
jmp LookupLoop
|
||||
|
||||
/* Accept the current string, with the maximum possible length. */
|
||||
|
||||
LenMaximum: movl deflatestate(%esp), %edx
|
||||
movl $MAX_MATCH, bestlen(%esp)
|
||||
movl %ecx, dsMatchStart(%edx)
|
||||
|
||||
/* if ((uInt)best_len <= s->lookahead) return (uInt)best_len; */
|
||||
/* return s->lookahead; */
|
||||
|
||||
LeaveNow:
|
||||
movl deflatestate(%esp), %edx
|
||||
movl bestlen(%esp), %ebx
|
||||
movl dsLookahead(%edx), %eax
|
||||
cmpl %eax, %ebx
|
||||
jg LookaheadRet
|
||||
movl %ebx, %eax
|
||||
LookaheadRet:
|
||||
|
||||
/* Restore the stack and return from whence we came. */
|
||||
|
||||
addl $LocalVarsSize, %esp
|
||||
popl %ebx
|
||||
popl %esi
|
||||
popl %edi
|
||||
popl %ebp
|
||||
match_init: ret
|
574
lib/libz/contrib/gcc_gvmat64/gvmat64.S
Normal file
574
lib/libz/contrib/gcc_gvmat64/gvmat64.S
Normal file
@ -0,0 +1,574 @@
|
||||
/*
|
||||
;uInt longest_match_x64(
|
||||
; deflate_state *s,
|
||||
; IPos cur_match); // current match
|
||||
|
||||
; gvmat64.S -- Asm portion of the optimized longest_match for 32 bits x86_64
|
||||
; (AMD64 on Athlon 64, Opteron, Phenom
|
||||
; and Intel EM64T on Pentium 4 with EM64T, Pentium D, Core 2 Duo, Core I5/I7)
|
||||
; this file is translation from gvmat64.asm to GCC 4.x (for Linux, Mac XCode)
|
||||
; Copyright (C) 1995-2010 Jean-loup Gailly, Brian Raiter and Gilles Vollant.
|
||||
;
|
||||
; File written by Gilles Vollant, by converting to assembly the longest_match
|
||||
; from Jean-loup Gailly in deflate.c of zLib and infoZip zip.
|
||||
; and by taking inspiration on asm686 with masm, optimised assembly code
|
||||
; from Brian Raiter, written 1998
|
||||
;
|
||||
; This software is provided 'as-is', without any express or implied
|
||||
; warranty. In no event will the authors be held liable for any damages
|
||||
; arising from the use of this software.
|
||||
;
|
||||
; Permission is granted to anyone to use this software for any purpose,
|
||||
; including commercial applications, and to alter it and redistribute it
|
||||
; freely, subject to the following restrictions:
|
||||
;
|
||||
; 1. The origin of this software must not be misrepresented; you must not
|
||||
; claim that you wrote the original software. If you use this software
|
||||
; in a product, an acknowledgment in the product documentation would be
|
||||
; appreciated but is not required.
|
||||
; 2. Altered source versions must be plainly marked as such, and must not be
|
||||
; misrepresented as being the original software
|
||||
; 3. This notice may not be removed or altered from any source distribution.
|
||||
;
|
||||
; http://www.zlib.net
|
||||
; http://www.winimage.com/zLibDll
|
||||
; http://www.muppetlabs.com/~breadbox/software/assembly.html
|
||||
;
|
||||
; to compile this file for zLib, I use option:
|
||||
; gcc -c -arch x86_64 gvmat64.S
|
||||
|
||||
|
||||
;uInt longest_match(s, cur_match)
|
||||
; deflate_state *s;
|
||||
; IPos cur_match; // current match /
|
||||
;
|
||||
; with XCode for Mac, I had strange error with some jump on intel syntax
|
||||
; this is why BEFORE_JMP and AFTER_JMP are used
|
||||
*/
|
||||
|
||||
|
||||
#define BEFORE_JMP .att_syntax
|
||||
#define AFTER_JMP .intel_syntax noprefix
|
||||
|
||||
#ifndef NO_UNDERLINE
|
||||
# define match_init _match_init
|
||||
# define longest_match _longest_match
|
||||
#endif
|
||||
|
||||
.intel_syntax noprefix
|
||||
|
||||
.globl match_init, longest_match
|
||||
.text
|
||||
longest_match:
|
||||
|
||||
|
||||
|
||||
#define LocalVarsSize 96
|
||||
/*
|
||||
; register used : rax,rbx,rcx,rdx,rsi,rdi,r8,r9,r10,r11,r12
|
||||
; free register : r14,r15
|
||||
; register can be saved : rsp
|
||||
*/
|
||||
|
||||
#define chainlenwmask (rsp + 8 - LocalVarsSize)
|
||||
#define nicematch (rsp + 16 - LocalVarsSize)
|
||||
|
||||
#define save_rdi (rsp + 24 - LocalVarsSize)
|
||||
#define save_rsi (rsp + 32 - LocalVarsSize)
|
||||
#define save_rbx (rsp + 40 - LocalVarsSize)
|
||||
#define save_rbp (rsp + 48 - LocalVarsSize)
|
||||
#define save_r12 (rsp + 56 - LocalVarsSize)
|
||||
#define save_r13 (rsp + 64 - LocalVarsSize)
|
||||
#define save_r14 (rsp + 72 - LocalVarsSize)
|
||||
#define save_r15 (rsp + 80 - LocalVarsSize)
|
||||
|
||||
|
||||
/*
|
||||
; all the +4 offsets are due to the addition of pending_buf_size (in zlib
|
||||
; in the deflate_state structure since the asm code was first written
|
||||
; (if you compile with zlib 1.0.4 or older, remove the +4).
|
||||
; Note : these value are good with a 8 bytes boundary pack structure
|
||||
*/
|
||||
|
||||
#define MAX_MATCH 258
|
||||
#define MIN_MATCH 3
|
||||
#define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1)
|
||||
|
||||
/*
|
||||
;;; Offsets for fields in the deflate_state structure. These numbers
|
||||
;;; are calculated from the definition of deflate_state, with the
|
||||
;;; assumption that the compiler will dword-align the fields. (Thus,
|
||||
;;; changing the definition of deflate_state could easily cause this
|
||||
;;; program to crash horribly, without so much as a warning at
|
||||
;;; compile time. Sigh.)
|
||||
|
||||
; all the +zlib1222add offsets are due to the addition of fields
|
||||
; in zlib in the deflate_state structure since the asm code was first written
|
||||
; (if you compile with zlib 1.0.4 or older, use "zlib1222add equ (-4)").
|
||||
; (if you compile with zlib between 1.0.5 and 1.2.2.1, use "zlib1222add equ 0").
|
||||
; if you compile with zlib 1.2.2.2 or later , use "zlib1222add equ 8").
|
||||
*/
|
||||
|
||||
|
||||
|
||||
/* you can check the structure offset by running
|
||||
|
||||
#include <stdlib.h>
|
||||
#include <stdio.h>
|
||||
#include "deflate.h"
|
||||
|
||||
void print_depl()
|
||||
{
|
||||
deflate_state ds;
|
||||
deflate_state *s=&ds;
|
||||
printf("size pointer=%u\n",(int)sizeof(void*));
|
||||
|
||||
printf("#define dsWSize %u\n",(int)(((char*)&(s->w_size))-((char*)s)));
|
||||
printf("#define dsWMask %u\n",(int)(((char*)&(s->w_mask))-((char*)s)));
|
||||
printf("#define dsWindow %u\n",(int)(((char*)&(s->window))-((char*)s)));
|
||||
printf("#define dsPrev %u\n",(int)(((char*)&(s->prev))-((char*)s)));
|
||||
printf("#define dsMatchLen %u\n",(int)(((char*)&(s->match_length))-((char*)s)));
|
||||
printf("#define dsPrevMatch %u\n",(int)(((char*)&(s->prev_match))-((char*)s)));
|
||||
printf("#define dsStrStart %u\n",(int)(((char*)&(s->strstart))-((char*)s)));
|
||||
printf("#define dsMatchStart %u\n",(int)(((char*)&(s->match_start))-((char*)s)));
|
||||
printf("#define dsLookahead %u\n",(int)(((char*)&(s->lookahead))-((char*)s)));
|
||||
printf("#define dsPrevLen %u\n",(int)(((char*)&(s->prev_length))-((char*)s)));
|
||||
printf("#define dsMaxChainLen %u\n",(int)(((char*)&(s->max_chain_length))-((char*)s)));
|
||||
printf("#define dsGoodMatch %u\n",(int)(((char*)&(s->good_match))-((char*)s)));
|
||||
printf("#define dsNiceMatch %u\n",(int)(((char*)&(s->nice_match))-((char*)s)));
|
||||
}
|
||||
*/
|
||||
|
||||
#define dsWSize 68
|
||||
#define dsWMask 76
|
||||
#define dsWindow 80
|
||||
#define dsPrev 96
|
||||
#define dsMatchLen 144
|
||||
#define dsPrevMatch 148
|
||||
#define dsStrStart 156
|
||||
#define dsMatchStart 160
|
||||
#define dsLookahead 164
|
||||
#define dsPrevLen 168
|
||||
#define dsMaxChainLen 172
|
||||
#define dsGoodMatch 188
|
||||
#define dsNiceMatch 192
|
||||
|
||||
#define window_size [ rcx + dsWSize]
|
||||
#define WMask [ rcx + dsWMask]
|
||||
#define window_ad [ rcx + dsWindow]
|
||||
#define prev_ad [ rcx + dsPrev]
|
||||
#define strstart [ rcx + dsStrStart]
|
||||
#define match_start [ rcx + dsMatchStart]
|
||||
#define Lookahead [ rcx + dsLookahead] //; 0ffffffffh on infozip
|
||||
#define prev_length [ rcx + dsPrevLen]
|
||||
#define max_chain_length [ rcx + dsMaxChainLen]
|
||||
#define good_match [ rcx + dsGoodMatch]
|
||||
#define nice_match [ rcx + dsNiceMatch]
|
||||
|
||||
/*
|
||||
; windows:
|
||||
; parameter 1 in rcx(deflate state s), param 2 in rdx (cur match)
|
||||
|
||||
; see http://weblogs.asp.net/oldnewthing/archive/2004/01/14/58579.aspx and
|
||||
; http://msdn.microsoft.com/library/en-us/kmarch/hh/kmarch/64bitAMD_8e951dd2-ee77-4728-8702-55ce4b5dd24a.xml.asp
|
||||
;
|
||||
; All registers must be preserved across the call, except for
|
||||
; rax, rcx, rdx, r8, r9, r10, and r11, which are scratch.
|
||||
|
||||
;
|
||||
; gcc on macosx-linux:
|
||||
; see http://www.x86-64.org/documentation/abi-0.99.pdf
|
||||
; param 1 in rdi, param 2 in rsi
|
||||
; rbx, rsp, rbp, r12 to r15 must be preserved
|
||||
|
||||
;;; Save registers that the compiler may be using, and adjust esp to
|
||||
;;; make room for our stack frame.
|
||||
|
||||
|
||||
;;; Retrieve the function arguments. r8d will hold cur_match
|
||||
;;; throughout the entire function. edx will hold the pointer to the
|
||||
;;; deflate_state structure during the function's setup (before
|
||||
;;; entering the main loop.
|
||||
|
||||
; ms: parameter 1 in rcx (deflate_state* s), param 2 in edx -> r8 (cur match)
|
||||
; mac: param 1 in rdi, param 2 rsi
|
||||
; this clear high 32 bits of r8, which can be garbage in both r8 and rdx
|
||||
*/
|
||||
mov [save_rbx],rbx
|
||||
mov [save_rbp],rbp
|
||||
|
||||
|
||||
mov rcx,rdi
|
||||
|
||||
mov r8d,esi
|
||||
|
||||
|
||||
mov [save_r12],r12
|
||||
mov [save_r13],r13
|
||||
mov [save_r14],r14
|
||||
mov [save_r15],r15
|
||||
|
||||
|
||||
//;;; uInt wmask = s->w_mask;
|
||||
//;;; unsigned chain_length = s->max_chain_length;
|
||||
//;;; if (s->prev_length >= s->good_match) {
|
||||
//;;; chain_length >>= 2;
|
||||
//;;; }
|
||||
|
||||
|
||||
mov edi, prev_length
|
||||
mov esi, good_match
|
||||
mov eax, WMask
|
||||
mov ebx, max_chain_length
|
||||
cmp edi, esi
|
||||
jl LastMatchGood
|
||||
shr ebx, 2
|
||||
LastMatchGood:
|
||||
|
||||
//;;; chainlen is decremented once beforehand so that the function can
|
||||
//;;; use the sign flag instead of the zero flag for the exit test.
|
||||
//;;; It is then shifted into the high word, to make room for the wmask
|
||||
//;;; value, which it will always accompany.
|
||||
|
||||
dec ebx
|
||||
shl ebx, 16
|
||||
or ebx, eax
|
||||
|
||||
//;;; on zlib only
|
||||
//;;; if ((uInt)nice_match > s->lookahead) nice_match = s->lookahead;
|
||||
|
||||
|
||||
|
||||
mov eax, nice_match
|
||||
mov [chainlenwmask], ebx
|
||||
mov r10d, Lookahead
|
||||
cmp r10d, eax
|
||||
cmovnl r10d, eax
|
||||
mov [nicematch],r10d
|
||||
|
||||
|
||||
|
||||
//;;; register Bytef *scan = s->window + s->strstart;
|
||||
mov r10, window_ad
|
||||
mov ebp, strstart
|
||||
lea r13, [r10 + rbp]
|
||||
|
||||
//;;; Determine how many bytes the scan ptr is off from being
|
||||
//;;; dword-aligned.
|
||||
|
||||
mov r9,r13
|
||||
neg r13
|
||||
and r13,3
|
||||
|
||||
//;;; IPos limit = s->strstart > (IPos)MAX_DIST(s) ?
|
||||
//;;; s->strstart - (IPos)MAX_DIST(s) : NIL;
|
||||
|
||||
|
||||
mov eax, window_size
|
||||
sub eax, MIN_LOOKAHEAD
|
||||
|
||||
|
||||
xor edi,edi
|
||||
sub ebp, eax
|
||||
|
||||
mov r11d, prev_length
|
||||
|
||||
cmovng ebp,edi
|
||||
|
||||
//;;; int best_len = s->prev_length;
|
||||
|
||||
|
||||
//;;; Store the sum of s->window + best_len in esi locally, and in esi.
|
||||
|
||||
lea rsi,[r10+r11]
|
||||
|
||||
//;;; register ush scan_start = *(ushf*)scan;
|
||||
//;;; register ush scan_end = *(ushf*)(scan+best_len-1);
|
||||
//;;; Posf *prev = s->prev;
|
||||
|
||||
movzx r12d,word ptr [r9]
|
||||
movzx ebx, word ptr [r9 + r11 - 1]
|
||||
|
||||
mov rdi, prev_ad
|
||||
|
||||
//;;; Jump into the main loop.
|
||||
|
||||
mov edx, [chainlenwmask]
|
||||
|
||||
cmp bx,word ptr [rsi + r8 - 1]
|
||||
jz LookupLoopIsZero
|
||||
|
||||
|
||||
|
||||
LookupLoop1:
|
||||
and r8d, edx
|
||||
|
||||
movzx r8d, word ptr [rdi + r8*2]
|
||||
cmp r8d, ebp
|
||||
jbe LeaveNow
|
||||
|
||||
|
||||
|
||||
sub edx, 0x00010000
|
||||
BEFORE_JMP
|
||||
js LeaveNow
|
||||
AFTER_JMP
|
||||
|
||||
LoopEntry1:
|
||||
cmp bx,word ptr [rsi + r8 - 1]
|
||||
BEFORE_JMP
|
||||
jz LookupLoopIsZero
|
||||
AFTER_JMP
|
||||
|
||||
LookupLoop2:
|
||||
and r8d, edx
|
||||
|
||||
movzx r8d, word ptr [rdi + r8*2]
|
||||
cmp r8d, ebp
|
||||
BEFORE_JMP
|
||||
jbe LeaveNow
|
||||
AFTER_JMP
|
||||
sub edx, 0x00010000
|
||||
BEFORE_JMP
|
||||
js LeaveNow
|
||||
AFTER_JMP
|
||||
|
||||
LoopEntry2:
|
||||
cmp bx,word ptr [rsi + r8 - 1]
|
||||
BEFORE_JMP
|
||||
jz LookupLoopIsZero
|
||||
AFTER_JMP
|
||||
|
||||
LookupLoop4:
|
||||
and r8d, edx
|
||||
|
||||
movzx r8d, word ptr [rdi + r8*2]
|
||||
cmp r8d, ebp
|
||||
BEFORE_JMP
|
||||
jbe LeaveNow
|
||||
AFTER_JMP
|
||||
sub edx, 0x00010000
|
||||
BEFORE_JMP
|
||||
js LeaveNow
|
||||
AFTER_JMP
|
||||
|
||||
LoopEntry4:
|
||||
|
||||
cmp bx,word ptr [rsi + r8 - 1]
|
||||
BEFORE_JMP
|
||||
jnz LookupLoop1
|
||||
jmp LookupLoopIsZero
|
||||
AFTER_JMP
|
||||
/*
|
||||
;;; do {
|
||||
;;; match = s->window + cur_match;
|
||||
;;; if (*(ushf*)(match+best_len-1) != scan_end ||
|
||||
;;; *(ushf*)match != scan_start) continue;
|
||||
;;; [...]
|
||||
;;; } while ((cur_match = prev[cur_match & wmask]) > limit
|
||||
;;; && --chain_length != 0);
|
||||
;;;
|
||||
;;; Here is the inner loop of the function. The function will spend the
|
||||
;;; majority of its time in this loop, and majority of that time will
|
||||
;;; be spent in the first ten instructions.
|
||||
;;;
|
||||
;;; Within this loop:
|
||||
;;; ebx = scanend
|
||||
;;; r8d = curmatch
|
||||
;;; edx = chainlenwmask - i.e., ((chainlen << 16) | wmask)
|
||||
;;; esi = windowbestlen - i.e., (window + bestlen)
|
||||
;;; edi = prev
|
||||
;;; ebp = limit
|
||||
*/
|
||||
.balign 16
|
||||
LookupLoop:
|
||||
and r8d, edx
|
||||
|
||||
movzx r8d, word ptr [rdi + r8*2]
|
||||
cmp r8d, ebp
|
||||
BEFORE_JMP
|
||||
jbe LeaveNow
|
||||
AFTER_JMP
|
||||
sub edx, 0x00010000
|
||||
BEFORE_JMP
|
||||
js LeaveNow
|
||||
AFTER_JMP
|
||||
|
||||
LoopEntry:
|
||||
|
||||
cmp bx,word ptr [rsi + r8 - 1]
|
||||
BEFORE_JMP
|
||||
jnz LookupLoop1
|
||||
AFTER_JMP
|
||||
LookupLoopIsZero:
|
||||
cmp r12w, word ptr [r10 + r8]
|
||||
BEFORE_JMP
|
||||
jnz LookupLoop1
|
||||
AFTER_JMP
|
||||
|
||||
|
||||
//;;; Store the current value of chainlen.
|
||||
mov [chainlenwmask], edx
|
||||
/*
|
||||
;;; Point edi to the string under scrutiny, and esi to the string we
|
||||
;;; are hoping to match it up with. In actuality, esi and edi are
|
||||
;;; both pointed (MAX_MATCH_8 - scanalign) bytes ahead, and edx is
|
||||
;;; initialized to -(MAX_MATCH_8 - scanalign).
|
||||
*/
|
||||
lea rsi,[r8+r10]
|
||||
mov rdx, 0xfffffffffffffef8 //; -(MAX_MATCH_8)
|
||||
lea rsi, [rsi + r13 + 0x0108] //;MAX_MATCH_8]
|
||||
lea rdi, [r9 + r13 + 0x0108] //;MAX_MATCH_8]
|
||||
|
||||
prefetcht1 [rsi+rdx]
|
||||
prefetcht1 [rdi+rdx]
|
||||
|
||||
/*
|
||||
;;; Test the strings for equality, 8 bytes at a time. At the end,
|
||||
;;; adjust rdx so that it is offset to the exact byte that mismatched.
|
||||
;;;
|
||||
;;; We already know at this point that the first three bytes of the
|
||||
;;; strings match each other, and they can be safely passed over before
|
||||
;;; starting the compare loop. So what this code does is skip over 0-3
|
||||
;;; bytes, as much as necessary in order to dword-align the edi
|
||||
;;; pointer. (rsi will still be misaligned three times out of four.)
|
||||
;;;
|
||||
;;; It should be confessed that this loop usually does not represent
|
||||
;;; much of the total running time. Replacing it with a more
|
||||
;;; straightforward "rep cmpsb" would not drastically degrade
|
||||
;;; performance.
|
||||
*/
|
||||
|
||||
LoopCmps:
|
||||
mov rax, [rsi + rdx]
|
||||
xor rax, [rdi + rdx]
|
||||
jnz LeaveLoopCmps
|
||||
|
||||
mov rax, [rsi + rdx + 8]
|
||||
xor rax, [rdi + rdx + 8]
|
||||
jnz LeaveLoopCmps8
|
||||
|
||||
|
||||
mov rax, [rsi + rdx + 8+8]
|
||||
xor rax, [rdi + rdx + 8+8]
|
||||
jnz LeaveLoopCmps16
|
||||
|
||||
add rdx,8+8+8
|
||||
|
||||
BEFORE_JMP
|
||||
jnz LoopCmps
|
||||
jmp LenMaximum
|
||||
AFTER_JMP
|
||||
|
||||
LeaveLoopCmps16: add rdx,8
|
||||
LeaveLoopCmps8: add rdx,8
|
||||
LeaveLoopCmps:
|
||||
|
||||
test eax, 0x0000FFFF
|
||||
jnz LenLower
|
||||
|
||||
test eax,0xffffffff
|
||||
|
||||
jnz LenLower32
|
||||
|
||||
add rdx,4
|
||||
shr rax,32
|
||||
or ax,ax
|
||||
BEFORE_JMP
|
||||
jnz LenLower
|
||||
AFTER_JMP
|
||||
|
||||
LenLower32:
|
||||
shr eax,16
|
||||
add rdx,2
|
||||
|
||||
LenLower:
|
||||
sub al, 1
|
||||
adc rdx, 0
|
||||
//;;; Calculate the length of the match. If it is longer than MAX_MATCH,
|
||||
//;;; then automatically accept it as the best possible match and leave.
|
||||
|
||||
lea rax, [rdi + rdx]
|
||||
sub rax, r9
|
||||
cmp eax, MAX_MATCH
|
||||
BEFORE_JMP
|
||||
jge LenMaximum
|
||||
AFTER_JMP
|
||||
/*
|
||||
;;; If the length of the match is not longer than the best match we
|
||||
;;; have so far, then forget it and return to the lookup loop.
|
||||
;///////////////////////////////////
|
||||
*/
|
||||
cmp eax, r11d
|
||||
jg LongerMatch
|
||||
|
||||
lea rsi,[r10+r11]
|
||||
|
||||
mov rdi, prev_ad
|
||||
mov edx, [chainlenwmask]
|
||||
BEFORE_JMP
|
||||
jmp LookupLoop
|
||||
AFTER_JMP
|
||||
/*
|
||||
;;; s->match_start = cur_match;
|
||||
;;; best_len = len;
|
||||
;;; if (len >= nice_match) break;
|
||||
;;; scan_end = *(ushf*)(scan+best_len-1);
|
||||
*/
|
||||
LongerMatch:
|
||||
mov r11d, eax
|
||||
mov match_start, r8d
|
||||
cmp eax, [nicematch]
|
||||
BEFORE_JMP
|
||||
jge LeaveNow
|
||||
AFTER_JMP
|
||||
|
||||
lea rsi,[r10+rax]
|
||||
|
||||
movzx ebx, word ptr [r9 + rax - 1]
|
||||
mov rdi, prev_ad
|
||||
mov edx, [chainlenwmask]
|
||||
BEFORE_JMP
|
||||
jmp LookupLoop
|
||||
AFTER_JMP
|
||||
|
||||
//;;; Accept the current string, with the maximum possible length.
|
||||
|
||||
LenMaximum:
|
||||
mov r11d,MAX_MATCH
|
||||
mov match_start, r8d
|
||||
|
||||
//;;; if ((uInt)best_len <= s->lookahead) return (uInt)best_len;
|
||||
//;;; return s->lookahead;
|
||||
|
||||
LeaveNow:
|
||||
mov eax, Lookahead
|
||||
cmp r11d, eax
|
||||
cmovng eax, r11d
|
||||
|
||||
|
||||
|
||||
//;;; Restore the stack and return from whence we came.
|
||||
|
||||
|
||||
// mov rsi,[save_rsi]
|
||||
// mov rdi,[save_rdi]
|
||||
mov rbx,[save_rbx]
|
||||
mov rbp,[save_rbp]
|
||||
mov r12,[save_r12]
|
||||
mov r13,[save_r13]
|
||||
mov r14,[save_r14]
|
||||
mov r15,[save_r15]
|
||||
|
||||
|
||||
ret 0
|
||||
//; please don't remove this string !
|
||||
//; Your can freely use gvmat64 in any free or commercial app
|
||||
//; but it is far better don't remove the string in the binary!
|
||||
// db 0dh,0ah,"asm686 with masm, optimised assembly code from Brian Raiter, written 1998, converted to amd 64 by Gilles Vollant 2005",0dh,0ah,0
|
||||
|
||||
|
||||
match_init:
|
||||
ret 0
|
||||
|
||||
|
@ -1,5 +1,5 @@
|
||||
/* crc32.c -- compute the CRC-32 of a data stream
|
||||
* Copyright (C) 1995-2005 Mark Adler
|
||||
* Copyright (C) 1995-2006 Mark Adler
|
||||
* For conditions of distribution and use, see copyright notice in zlib.h
|
||||
*
|
||||
* Thanks to Rodney Brown <rbrown64@csc.com.au> for his contribution of faster
|
||||
@ -53,7 +53,7 @@
|
||||
|
||||
/* Definitions for doing the crc four data bytes at a time. */
|
||||
#ifdef BYFOUR
|
||||
# define REV(w) (((w)>>24)+(((w)>>8)&0xff00)+ \
|
||||
# define REV(w) ((((w)>>24)&0xff)+(((w)>>8)&0xff00)+ \
|
||||
(((w)&0xff00)<<8)+(((w)&0xff)<<24))
|
||||
local unsigned long crc32_little OF((unsigned long,
|
||||
const unsigned char FAR *, unsigned));
|
||||
@ -68,6 +68,8 @@
|
||||
local unsigned long gf2_matrix_times OF((unsigned long *mat,
|
||||
unsigned long vec));
|
||||
local void gf2_matrix_square OF((unsigned long *square, unsigned long *mat));
|
||||
local uLong crc32_combine_(uLong crc1, uLong crc2, z_off64_t len2);
|
||||
|
||||
|
||||
#ifdef DYNAMIC_CRC_TABLE
|
||||
|
||||
@ -367,22 +369,22 @@ local void gf2_matrix_square(square, mat)
|
||||
}
|
||||
|
||||
/* ========================================================================= */
|
||||
uLong ZEXPORT crc32_combine(crc1, crc2, len2)
|
||||
local uLong crc32_combine_(crc1, crc2, len2)
|
||||
uLong crc1;
|
||||
uLong crc2;
|
||||
z_off_t len2;
|
||||
z_off64_t len2;
|
||||
{
|
||||
int n;
|
||||
unsigned long row;
|
||||
unsigned long even[GF2_DIM]; /* even-power-of-two zeros operator */
|
||||
unsigned long odd[GF2_DIM]; /* odd-power-of-two zeros operator */
|
||||
|
||||
/* degenerate case */
|
||||
if (len2 == 0)
|
||||
/* degenerate case (also disallow negative lengths) */
|
||||
if (len2 <= 0)
|
||||
return crc1;
|
||||
|
||||
/* put operator for one zero bit in odd */
|
||||
odd[0] = 0xedb88320L; /* CRC-32 polynomial */
|
||||
odd[0] = 0xedb88320UL; /* CRC-32 polynomial */
|
||||
row = 1;
|
||||
for (n = 1; n < GF2_DIM; n++) {
|
||||
odd[n] = row;
|
||||
@ -421,3 +423,20 @@ uLong ZEXPORT crc32_combine(crc1, crc2, len2)
|
||||
crc1 ^= crc2;
|
||||
return crc1;
|
||||
}
|
||||
|
||||
/* ========================================================================= */
|
||||
uLong ZEXPORT crc32_combine(crc1, crc2, len2)
|
||||
uLong crc1;
|
||||
uLong crc2;
|
||||
z_off_t len2;
|
||||
{
|
||||
return crc32_combine_(crc1, crc2, len2);
|
||||
}
|
||||
|
||||
uLong ZEXPORT crc32_combine64(crc1, crc2, len2)
|
||||
uLong crc1;
|
||||
uLong crc2;
|
||||
z_off64_t len2;
|
||||
{
|
||||
return crc32_combine_(crc1, crc2, len2);
|
||||
}
|
||||
|
@ -1,5 +1,5 @@
|
||||
/* deflate.c -- compress data using the deflation algorithm
|
||||
* Copyright (C) 1995-2005 Jean-loup Gailly.
|
||||
* Copyright (C) 1995-2010 Jean-loup Gailly and Mark Adler
|
||||
* For conditions of distribution and use, see copyright notice in zlib.h
|
||||
*/
|
||||
|
||||
@ -52,7 +52,7 @@
|
||||
#include "deflate.h"
|
||||
|
||||
const char deflate_copyright[] =
|
||||
" deflate 1.2.3 Copyright 1995-2005 Jean-loup Gailly ";
|
||||
" deflate 1.2.4 Copyright 1995-2010 Jean-loup Gailly and Mark Adler ";
|
||||
/*
|
||||
If you use the zlib library in a product, an acknowledgment is welcome
|
||||
in the documentation of your product. If for some reason you cannot
|
||||
@ -79,19 +79,18 @@ local block_state deflate_fast OF((deflate_state *s, int flush));
|
||||
#ifndef FASTEST
|
||||
local block_state deflate_slow OF((deflate_state *s, int flush));
|
||||
#endif
|
||||
local block_state deflate_rle OF((deflate_state *s, int flush));
|
||||
local block_state deflate_huff OF((deflate_state *s, int flush));
|
||||
local void lm_init OF((deflate_state *s));
|
||||
local void putShortMSB OF((deflate_state *s, uInt b));
|
||||
local void flush_pending OF((z_streamp strm));
|
||||
local int read_buf OF((z_streamp strm, Bytef *buf, unsigned size));
|
||||
#ifndef FASTEST
|
||||
#ifdef ASMV
|
||||
void match_init OF((void)); /* asm code initialization */
|
||||
uInt longest_match OF((deflate_state *s, IPos cur_match));
|
||||
#else
|
||||
local uInt longest_match OF((deflate_state *s, IPos cur_match));
|
||||
#endif
|
||||
#endif
|
||||
local uInt longest_match_fast OF((deflate_state *s, IPos cur_match));
|
||||
|
||||
#ifdef DEBUG
|
||||
local void check_match OF((deflate_state *s, IPos start, IPos match,
|
||||
@ -110,11 +109,6 @@ local void check_match OF((deflate_state *s, IPos start, IPos match,
|
||||
#endif
|
||||
/* Matches of length 3 are discarded if their distance exceeds TOO_FAR */
|
||||
|
||||
#define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1)
|
||||
/* Minimum amount of lookahead, except at the end of the input file.
|
||||
* See deflate.c for comments about the MIN_MATCH+1.
|
||||
*/
|
||||
|
||||
/* Values for max_lazy_match, good_match and max_chain_length, depending on
|
||||
* the desired pack level (0..9). The values given below have been tuned to
|
||||
* exclude worst case performance for pathological files. Better values may be
|
||||
@ -288,6 +282,8 @@ int ZEXPORT deflateInit2_(strm, level, method, windowBits, memLevel, strategy,
|
||||
s->prev = (Posf *) ZALLOC(strm, s->w_size, sizeof(Pos));
|
||||
s->head = (Posf *) ZALLOC(strm, s->hash_size, sizeof(Pos));
|
||||
|
||||
s->high_water = 0; /* nothing written to s->window yet */
|
||||
|
||||
s->lit_bufsize = 1 << (memLevel + 6); /* 16K elements by default */
|
||||
|
||||
overlay = (ushf *) ZALLOC(strm, s->lit_bufsize, sizeof(ush)+2);
|
||||
@ -332,8 +328,8 @@ int ZEXPORT deflateSetDictionary (strm, dictionary, dictLength)
|
||||
strm->adler = adler32(strm->adler, dictionary, dictLength);
|
||||
|
||||
if (length < MIN_MATCH) return Z_OK;
|
||||
if (length > MAX_DIST(s)) {
|
||||
length = MAX_DIST(s);
|
||||
if (length > s->w_size) {
|
||||
length = s->w_size;
|
||||
dictionary += dictLength - length; /* use the tail of the dictionary */
|
||||
}
|
||||
zmemcpy(s->window, dictionary, length);
|
||||
@ -435,9 +431,10 @@ int ZEXPORT deflateParams(strm, level, strategy)
|
||||
}
|
||||
func = configuration_table[s->level].func;
|
||||
|
||||
if (func != configuration_table[level].func && strm->total_in != 0) {
|
||||
if ((strategy != s->strategy || func != configuration_table[level].func) &&
|
||||
strm->total_in != 0) {
|
||||
/* Flush the last buffer: */
|
||||
err = deflate(strm, Z_PARTIAL_FLUSH);
|
||||
err = deflate(strm, Z_BLOCK);
|
||||
}
|
||||
if (s->level != level) {
|
||||
s->level = level;
|
||||
@ -481,33 +478,66 @@ int ZEXPORT deflateTune(strm, good_length, max_lazy, nice_length, max_chain)
|
||||
* resulting from using fixed blocks instead of stored blocks, which deflate
|
||||
* can emit on compressed data for some combinations of the parameters.
|
||||
*
|
||||
* This function could be more sophisticated to provide closer upper bounds
|
||||
* for every combination of windowBits and memLevel, as well as wrap.
|
||||
* But even the conservative upper bound of about 14% expansion does not
|
||||
* seem onerous for output buffer allocation.
|
||||
* This function could be more sophisticated to provide closer upper bounds for
|
||||
* every combination of windowBits and memLevel. But even the conservative
|
||||
* upper bound of about 14% expansion does not seem onerous for output buffer
|
||||
* allocation.
|
||||
*/
|
||||
uLong ZEXPORT deflateBound(strm, sourceLen)
|
||||
z_streamp strm;
|
||||
uLong sourceLen;
|
||||
{
|
||||
deflate_state *s;
|
||||
uLong destLen;
|
||||
uLong complen, wraplen;
|
||||
Bytef *str;
|
||||
|
||||
/* conservative upper bound */
|
||||
destLen = sourceLen +
|
||||
((sourceLen + 7) >> 3) + ((sourceLen + 63) >> 6) + 11;
|
||||
/* conservative upper bound for compressed data */
|
||||
complen = sourceLen +
|
||||
((sourceLen + 7) >> 3) + ((sourceLen + 63) >> 6) + 5;
|
||||
|
||||
/* if can't get parameters, return conservative bound */
|
||||
/* if can't get parameters, return conservative bound plus zlib wrapper */
|
||||
if (strm == Z_NULL || strm->state == Z_NULL)
|
||||
return destLen;
|
||||
return complen + 6;
|
||||
|
||||
/* compute wrapper length */
|
||||
s = strm->state;
|
||||
switch (s->wrap) {
|
||||
case 0: /* raw deflate */
|
||||
wraplen = 0;
|
||||
break;
|
||||
case 1: /* zlib wrapper */
|
||||
wraplen = 6 + (s->strstart ? 4 : 0);
|
||||
break;
|
||||
case 2: /* gzip wrapper */
|
||||
wraplen = 18;
|
||||
if (s->gzhead != Z_NULL) { /* user-supplied gzip header */
|
||||
if (s->gzhead->extra != Z_NULL)
|
||||
wraplen += 2 + s->gzhead->extra_len;
|
||||
str = s->gzhead->name;
|
||||
if (str != Z_NULL)
|
||||
do {
|
||||
wraplen++;
|
||||
} while (*str++);
|
||||
str = s->gzhead->comment;
|
||||
if (str != Z_NULL)
|
||||
do {
|
||||
wraplen++;
|
||||
} while (*str++);
|
||||
if (s->gzhead->hcrc)
|
||||
wraplen += 2;
|
||||
}
|
||||
break;
|
||||
default: /* for compiler happiness */
|
||||
wraplen = 6;
|
||||
}
|
||||
|
||||
/* if not default parameters, return conservative bound */
|
||||
s = strm->state;
|
||||
if (s->w_bits != 15 || s->hash_bits != 8 + 7)
|
||||
return destLen;
|
||||
return complen + wraplen;
|
||||
|
||||
/* default settings: return tight bound for that case */
|
||||
return compressBound(sourceLen);
|
||||
return sourceLen + (sourceLen >> 12) + (sourceLen >> 14) +
|
||||
(sourceLen >> 25) + 13 - 6 + wraplen;
|
||||
}
|
||||
|
||||
/* =========================================================================
|
||||
@ -557,7 +587,7 @@ int ZEXPORT deflate (strm, flush)
|
||||
deflate_state *s;
|
||||
|
||||
if (strm == Z_NULL || strm->state == Z_NULL ||
|
||||
flush > Z_FINISH || flush < 0) {
|
||||
flush > Z_BLOCK || flush < 0) {
|
||||
return Z_STREAM_ERROR;
|
||||
}
|
||||
s = strm->state;
|
||||
@ -581,7 +611,7 @@ int ZEXPORT deflate (strm, flush)
|
||||
put_byte(s, 31);
|
||||
put_byte(s, 139);
|
||||
put_byte(s, 8);
|
||||
if (s->gzhead == NULL) {
|
||||
if (s->gzhead == Z_NULL) {
|
||||
put_byte(s, 0);
|
||||
put_byte(s, 0);
|
||||
put_byte(s, 0);
|
||||
@ -608,7 +638,7 @@ int ZEXPORT deflate (strm, flush)
|
||||
(s->strategy >= Z_HUFFMAN_ONLY || s->level < 2 ?
|
||||
4 : 0));
|
||||
put_byte(s, s->gzhead->os & 0xff);
|
||||
if (s->gzhead->extra != NULL) {
|
||||
if (s->gzhead->extra != Z_NULL) {
|
||||
put_byte(s, s->gzhead->extra_len & 0xff);
|
||||
put_byte(s, (s->gzhead->extra_len >> 8) & 0xff);
|
||||
}
|
||||
@ -650,7 +680,7 @@ int ZEXPORT deflate (strm, flush)
|
||||
}
|
||||
#ifdef GZIP
|
||||
if (s->status == EXTRA_STATE) {
|
||||
if (s->gzhead->extra != NULL) {
|
||||
if (s->gzhead->extra != Z_NULL) {
|
||||
uInt beg = s->pending; /* start of bytes to update crc */
|
||||
|
||||
while (s->gzindex < (s->gzhead->extra_len & 0xffff)) {
|
||||
@ -678,7 +708,7 @@ int ZEXPORT deflate (strm, flush)
|
||||
s->status = NAME_STATE;
|
||||
}
|
||||
if (s->status == NAME_STATE) {
|
||||
if (s->gzhead->name != NULL) {
|
||||
if (s->gzhead->name != Z_NULL) {
|
||||
uInt beg = s->pending; /* start of bytes to update crc */
|
||||
int val;
|
||||
|
||||
@ -709,7 +739,7 @@ int ZEXPORT deflate (strm, flush)
|
||||
s->status = COMMENT_STATE;
|
||||
}
|
||||
if (s->status == COMMENT_STATE) {
|
||||
if (s->gzhead->comment != NULL) {
|
||||
if (s->gzhead->comment != Z_NULL) {
|
||||
uInt beg = s->pending; /* start of bytes to update crc */
|
||||
int val;
|
||||
|
||||
@ -787,7 +817,9 @@ int ZEXPORT deflate (strm, flush)
|
||||
(flush != Z_NO_FLUSH && s->status != FINISH_STATE)) {
|
||||
block_state bstate;
|
||||
|
||||
bstate = (*(configuration_table[s->level].func))(s, flush);
|
||||
bstate = s->strategy == Z_HUFFMAN_ONLY ? deflate_huff(s, flush) :
|
||||
(s->strategy == Z_RLE ? deflate_rle(s, flush) :
|
||||
(*(configuration_table[s->level].func))(s, flush));
|
||||
|
||||
if (bstate == finish_started || bstate == finish_done) {
|
||||
s->status = FINISH_STATE;
|
||||
@ -808,13 +840,17 @@ int ZEXPORT deflate (strm, flush)
|
||||
if (bstate == block_done) {
|
||||
if (flush == Z_PARTIAL_FLUSH) {
|
||||
_tr_align(s);
|
||||
} else { /* FULL_FLUSH or SYNC_FLUSH */
|
||||
} else if (flush != Z_BLOCK) { /* FULL_FLUSH or SYNC_FLUSH */
|
||||
_tr_stored_block(s, (char*)0, 0L, 0);
|
||||
/* For a full flush, this empty block will be recognized
|
||||
* as a special marker by inflate_sync().
|
||||
*/
|
||||
if (flush == Z_FULL_FLUSH) {
|
||||
CLEAR_HASH(s); /* forget history */
|
||||
if (s->lookahead == 0) {
|
||||
s->strstart = 0;
|
||||
s->block_start = 0L;
|
||||
}
|
||||
}
|
||||
}
|
||||
flush_pending(strm);
|
||||
@ -1167,12 +1203,13 @@ local uInt longest_match(s, cur_match)
|
||||
return s->lookahead;
|
||||
}
|
||||
#endif /* ASMV */
|
||||
#endif /* FASTEST */
|
||||
|
||||
#else /* FASTEST */
|
||||
|
||||
/* ---------------------------------------------------------------------------
|
||||
* Optimized version for level == 1 or strategy == Z_RLE only
|
||||
* Optimized version for FASTEST only
|
||||
*/
|
||||
local uInt longest_match_fast(s, cur_match)
|
||||
local uInt longest_match(s, cur_match)
|
||||
deflate_state *s;
|
||||
IPos cur_match; /* current match */
|
||||
{
|
||||
@ -1225,6 +1262,8 @@ local uInt longest_match_fast(s, cur_match)
|
||||
return (uInt)len <= s->lookahead ? (uInt)len : s->lookahead;
|
||||
}
|
||||
|
||||
#endif /* FASTEST */
|
||||
|
||||
#ifdef DEBUG
|
||||
/* ===========================================================================
|
||||
* Check that the match at match_start is indeed a match.
|
||||
@ -1303,7 +1342,6 @@ local void fill_window(s)
|
||||
later. (Using level 0 permanently is not an optimal usage of
|
||||
zlib, so we don't care about this pathological case.)
|
||||
*/
|
||||
/* %%% avoid this when Z_RLE */
|
||||
n = s->hash_size;
|
||||
p = &s->head[n];
|
||||
do {
|
||||
@ -1355,27 +1393,61 @@ local void fill_window(s)
|
||||
*/
|
||||
|
||||
} while (s->lookahead < MIN_LOOKAHEAD && s->strm->avail_in != 0);
|
||||
|
||||
/* If the WIN_INIT bytes after the end of the current data have never been
|
||||
* written, then zero those bytes in order to avoid memory check reports of
|
||||
* the use of uninitialized (or uninitialised as Julian writes) bytes by
|
||||
* the longest match routines. Update the high water mark for the next
|
||||
* time through here. WIN_INIT is set to MAX_MATCH since the longest match
|
||||
* routines allow scanning to strstart + MAX_MATCH, ignoring lookahead.
|
||||
*/
|
||||
if (s->high_water < s->window_size) {
|
||||
ulg curr = s->strstart + (ulg)(s->lookahead);
|
||||
ulg init;
|
||||
|
||||
if (s->high_water < curr) {
|
||||
/* Previous high water mark below current data -- zero WIN_INIT
|
||||
* bytes or up to end of window, whichever is less.
|
||||
*/
|
||||
init = s->window_size - curr;
|
||||
if (init > WIN_INIT)
|
||||
init = WIN_INIT;
|
||||
zmemzero(s->window + curr, (unsigned)init);
|
||||
s->high_water = curr + init;
|
||||
}
|
||||
else if (s->high_water < (ulg)curr + WIN_INIT) {
|
||||
/* High water mark at or above current data, but below current data
|
||||
* plus WIN_INIT -- zero out to current data plus WIN_INIT, or up
|
||||
* to end of window, whichever is less.
|
||||
*/
|
||||
init = (ulg)curr + WIN_INIT - s->high_water;
|
||||
if (init > s->window_size - s->high_water)
|
||||
init = s->window_size - s->high_water;
|
||||
zmemzero(s->window + s->high_water, (unsigned)init);
|
||||
s->high_water += init;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/* ===========================================================================
|
||||
* Flush the current block, with given end-of-file flag.
|
||||
* IN assertion: strstart is set to the end of the current match.
|
||||
*/
|
||||
#define FLUSH_BLOCK_ONLY(s, eof) { \
|
||||
#define FLUSH_BLOCK_ONLY(s, last) { \
|
||||
_tr_flush_block(s, (s->block_start >= 0L ? \
|
||||
(charf *)&s->window[(unsigned)s->block_start] : \
|
||||
(charf *)Z_NULL), \
|
||||
(ulg)((long)s->strstart - s->block_start), \
|
||||
(eof)); \
|
||||
(last)); \
|
||||
s->block_start = s->strstart; \
|
||||
flush_pending(s->strm); \
|
||||
Tracev((stderr,"[FLUSH]")); \
|
||||
}
|
||||
|
||||
/* Same but force premature exit if necessary. */
|
||||
#define FLUSH_BLOCK(s, eof) { \
|
||||
FLUSH_BLOCK_ONLY(s, eof); \
|
||||
if (s->strm->avail_out == 0) return (eof) ? finish_started : need_more; \
|
||||
#define FLUSH_BLOCK(s, last) { \
|
||||
FLUSH_BLOCK_ONLY(s, last); \
|
||||
if (s->strm->avail_out == 0) return (last) ? finish_started : need_more; \
|
||||
}
|
||||
|
||||
/* ===========================================================================
|
||||
@ -1449,7 +1521,7 @@ local block_state deflate_fast(s, flush)
|
||||
deflate_state *s;
|
||||
int flush;
|
||||
{
|
||||
IPos hash_head = NIL; /* head of the hash chain */
|
||||
IPos hash_head; /* head of the hash chain */
|
||||
int bflush; /* set if current block must be flushed */
|
||||
|
||||
for (;;) {
|
||||
@ -1469,6 +1541,7 @@ local block_state deflate_fast(s, flush)
|
||||
/* Insert the string window[strstart .. strstart+2] in the
|
||||
* dictionary, and set hash_head to the head of the hash chain:
|
||||
*/
|
||||
hash_head = NIL;
|
||||
if (s->lookahead >= MIN_MATCH) {
|
||||
INSERT_STRING(s, s->strstart, hash_head);
|
||||
}
|
||||
@ -1481,19 +1554,8 @@ local block_state deflate_fast(s, flush)
|
||||
* of window index 0 (in particular we have to avoid a match
|
||||
* of the string with itself at the start of the input file).
|
||||
*/
|
||||
#ifdef FASTEST
|
||||
if ((s->strategy != Z_HUFFMAN_ONLY && s->strategy != Z_RLE) ||
|
||||
(s->strategy == Z_RLE && s->strstart - hash_head == 1)) {
|
||||
s->match_length = longest_match_fast (s, hash_head);
|
||||
}
|
||||
#else
|
||||
if (s->strategy != Z_HUFFMAN_ONLY && s->strategy != Z_RLE) {
|
||||
s->match_length = longest_match (s, hash_head);
|
||||
} else if (s->strategy == Z_RLE && s->strstart - hash_head == 1) {
|
||||
s->match_length = longest_match_fast (s, hash_head);
|
||||
}
|
||||
#endif
|
||||
/* longest_match() or longest_match_fast() sets match_start */
|
||||
s->match_length = longest_match (s, hash_head);
|
||||
/* longest_match() sets match_start */
|
||||
}
|
||||
if (s->match_length >= MIN_MATCH) {
|
||||
check_match(s, s->strstart, s->match_start, s->match_length);
|
||||
@ -1555,7 +1617,7 @@ local block_state deflate_slow(s, flush)
|
||||
deflate_state *s;
|
||||
int flush;
|
||||
{
|
||||
IPos hash_head = NIL; /* head of hash chain */
|
||||
IPos hash_head; /* head of hash chain */
|
||||
int bflush; /* set if current block must be flushed */
|
||||
|
||||
/* Process the input block. */
|
||||
@ -1576,6 +1638,7 @@ local block_state deflate_slow(s, flush)
|
||||
/* Insert the string window[strstart .. strstart+2] in the
|
||||
* dictionary, and set hash_head to the head of the hash chain:
|
||||
*/
|
||||
hash_head = NIL;
|
||||
if (s->lookahead >= MIN_MATCH) {
|
||||
INSERT_STRING(s, s->strstart, hash_head);
|
||||
}
|
||||
@ -1591,12 +1654,8 @@ local block_state deflate_slow(s, flush)
|
||||
* of window index 0 (in particular we have to avoid a match
|
||||
* of the string with itself at the start of the input file).
|
||||
*/
|
||||
if (s->strategy != Z_HUFFMAN_ONLY && s->strategy != Z_RLE) {
|
||||
s->match_length = longest_match (s, hash_head);
|
||||
} else if (s->strategy == Z_RLE && s->strstart - hash_head == 1) {
|
||||
s->match_length = longest_match_fast (s, hash_head);
|
||||
}
|
||||
/* longest_match() or longest_match_fast() sets match_start */
|
||||
s->match_length = longest_match (s, hash_head);
|
||||
/* longest_match() sets match_start */
|
||||
|
||||
if (s->match_length <= 5 && (s->strategy == Z_FILTERED
|
||||
#if TOO_FAR <= 32767
|
||||
@ -1674,7 +1733,6 @@ local block_state deflate_slow(s, flush)
|
||||
}
|
||||
#endif /* FASTEST */
|
||||
|
||||
#if 0
|
||||
/* ===========================================================================
|
||||
* For Z_RLE, simply look for runs of bytes, generate matches only of distance
|
||||
* one. Do not maintain a hash table. (It will be regenerated if this run of
|
||||
@ -1684,11 +1742,9 @@ local block_state deflate_rle(s, flush)
|
||||
deflate_state *s;
|
||||
int flush;
|
||||
{
|
||||
int bflush; /* set if current block must be flushed */
|
||||
uInt run; /* length of run */
|
||||
uInt max; /* maximum length of run */
|
||||
uInt prev; /* byte at distance one to match */
|
||||
Bytef *scan; /* scan for end of run */
|
||||
int bflush; /* set if current block must be flushed */
|
||||
uInt prev; /* byte at distance one to match */
|
||||
Bytef *scan, *strend; /* scan goes up to strend for length of run */
|
||||
|
||||
for (;;) {
|
||||
/* Make sure that we always have enough lookahead, except
|
||||
@ -1704,23 +1760,33 @@ local block_state deflate_rle(s, flush)
|
||||
}
|
||||
|
||||
/* See how many times the previous byte repeats */
|
||||
run = 0;
|
||||
if (s->strstart > 0) { /* if there is a previous byte, that is */
|
||||
max = s->lookahead < MAX_MATCH ? s->lookahead : MAX_MATCH;
|
||||
s->match_length = 0;
|
||||
if (s->lookahead >= MIN_MATCH && s->strstart > 0) {
|
||||
scan = s->window + s->strstart - 1;
|
||||
prev = *scan++;
|
||||
do {
|
||||
if (*scan++ != prev)
|
||||
break;
|
||||
} while (++run < max);
|
||||
prev = *scan;
|
||||
if (prev == *++scan && prev == *++scan && prev == *++scan) {
|
||||
strend = s->window + s->strstart + MAX_MATCH;
|
||||
do {
|
||||
} while (prev == *++scan && prev == *++scan &&
|
||||
prev == *++scan && prev == *++scan &&
|
||||
prev == *++scan && prev == *++scan &&
|
||||
prev == *++scan && prev == *++scan &&
|
||||
scan < strend);
|
||||
s->match_length = MAX_MATCH - (int)(strend - scan);
|
||||
if (s->match_length > s->lookahead)
|
||||
s->match_length = s->lookahead;
|
||||
}
|
||||
}
|
||||
|
||||
/* Emit match if have run of MIN_MATCH or longer, else emit literal */
|
||||
if (run >= MIN_MATCH) {
|
||||
check_match(s, s->strstart, s->strstart - 1, run);
|
||||
_tr_tally_dist(s, 1, run - MIN_MATCH, bflush);
|
||||
s->lookahead -= run;
|
||||
s->strstart += run;
|
||||
if (s->match_length >= MIN_MATCH) {
|
||||
check_match(s, s->strstart, s->strstart - 1, s->match_length);
|
||||
|
||||
_tr_tally_dist(s, 1, s->match_length - MIN_MATCH, bflush);
|
||||
|
||||
s->lookahead -= s->match_length;
|
||||
s->strstart += s->match_length;
|
||||
s->match_length = 0;
|
||||
} else {
|
||||
/* No match, output a literal byte */
|
||||
Tracevv((stderr,"%c", s->window[s->strstart]));
|
||||
@ -1733,4 +1799,36 @@ local block_state deflate_rle(s, flush)
|
||||
FLUSH_BLOCK(s, flush == Z_FINISH);
|
||||
return flush == Z_FINISH ? finish_done : block_done;
|
||||
}
|
||||
#endif
|
||||
|
||||
/* ===========================================================================
|
||||
* For Z_HUFFMAN_ONLY, do not look for matches. Do not maintain a hash table.
|
||||
* (It will be regenerated if this run of deflate switches away from Huffman.)
|
||||
*/
|
||||
local block_state deflate_huff(s, flush)
|
||||
deflate_state *s;
|
||||
int flush;
|
||||
{
|
||||
int bflush; /* set if current block must be flushed */
|
||||
|
||||
for (;;) {
|
||||
/* Make sure that we have a literal to write. */
|
||||
if (s->lookahead == 0) {
|
||||
fill_window(s);
|
||||
if (s->lookahead == 0) {
|
||||
if (flush == Z_NO_FLUSH)
|
||||
return need_more;
|
||||
break; /* flush the current block */
|
||||
}
|
||||
}
|
||||
|
||||
/* Output a literal byte */
|
||||
s->match_length = 0;
|
||||
Tracevv((stderr,"%c", s->window[s->strstart]));
|
||||
_tr_tally_lit (s, s->window[s->strstart], bflush);
|
||||
s->lookahead--;
|
||||
s->strstart++;
|
||||
if (bflush) FLUSH_BLOCK(s, 0);
|
||||
}
|
||||
FLUSH_BLOCK(s, flush == Z_FINISH);
|
||||
return flush == Z_FINISH ? finish_done : block_done;
|
||||
}
|
||||
|
@ -1,5 +1,5 @@
|
||||
/* deflate.h -- internal compression state
|
||||
* Copyright (C) 1995-2004 Jean-loup Gailly
|
||||
* Copyright (C) 1995-2009 Jean-loup Gailly
|
||||
* For conditions of distribution and use, see copyright notice in zlib.h
|
||||
*/
|
||||
|
||||
@ -260,6 +260,13 @@ typedef struct internal_state {
|
||||
* are always zero.
|
||||
*/
|
||||
|
||||
ulg high_water;
|
||||
/* High water mark offset in window for initialized bytes -- bytes above
|
||||
* this are set to zero in order to avoid memory check warnings when
|
||||
* longest match routines access bytes past the input. This is then
|
||||
* updated to the new high water mark.
|
||||
*/
|
||||
|
||||
} FAR deflate_state;
|
||||
|
||||
/* Output a byte on the stream.
|
||||
@ -278,14 +285,18 @@ typedef struct internal_state {
|
||||
* distances are limited to MAX_DIST instead of WSIZE.
|
||||
*/
|
||||
|
||||
#define WIN_INIT MAX_MATCH
|
||||
/* Number of bytes after end of data in window to initialize in order to avoid
|
||||
memory checker errors from longest match routines */
|
||||
|
||||
/* in trees.c */
|
||||
void _tr_init OF((deflate_state *s));
|
||||
int _tr_tally OF((deflate_state *s, unsigned dist, unsigned lc));
|
||||
void _tr_flush_block OF((deflate_state *s, charf *buf, ulg stored_len,
|
||||
int eof));
|
||||
int last));
|
||||
void _tr_align OF((deflate_state *s));
|
||||
void _tr_stored_block OF((deflate_state *s, charf *buf, ulg stored_len,
|
||||
int eof));
|
||||
int last));
|
||||
|
||||
#define d_code(dist) \
|
||||
((dist) < 256 ? _dist_code[dist] : _dist_code[256+((dist)>>7)])
|
||||
|
@ -121,7 +121,7 @@ At least for deflate's output that generates new trees every several 10's of
|
||||
kbytes. You can imagine that filling in a 2^15 entry table for a 15-bit code
|
||||
would take too long if you're only decoding several thousand symbols. At the
|
||||
other extreme, you could make a new table for every bit in the code. In fact,
|
||||
that's essentially a Huffman tree. But then you spend two much time
|
||||
that's essentially a Huffman tree. But then you spend too much time
|
||||
traversing the tree while decoding, even for short symbols.
|
||||
|
||||
So the number of bits for the first lookup table is a trade of the time to
|
619
lib/libz/doc/rfc1950.txt
Normal file
619
lib/libz/doc/rfc1950.txt
Normal file
@ -0,0 +1,619 @@
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
Network Working Group P. Deutsch
|
||||
Request for Comments: 1950 Aladdin Enterprises
|
||||
Category: Informational J-L. Gailly
|
||||
Info-ZIP
|
||||
May 1996
|
||||
|
||||
|
||||
ZLIB Compressed Data Format Specification version 3.3
|
||||
|
||||
Status of This Memo
|
||||
|
||||
This memo provides information for the Internet community. This memo
|
||||
does not specify an Internet standard of any kind. Distribution of
|
||||
this memo is unlimited.
|
||||
|
||||
IESG Note:
|
||||
|
||||
The IESG takes no position on the validity of any Intellectual
|
||||
Property Rights statements contained in this document.
|
||||
|
||||
Notices
|
||||
|
||||
Copyright (c) 1996 L. Peter Deutsch and Jean-Loup Gailly
|
||||
|
||||
Permission is granted to copy and distribute this document for any
|
||||
purpose and without charge, including translations into other
|
||||
languages and incorporation into compilations, provided that the
|
||||
copyright notice and this notice are preserved, and that any
|
||||
substantive changes or deletions from the original are clearly
|
||||
marked.
|
||||
|
||||
A pointer to the latest version of this and related documentation in
|
||||
HTML format can be found at the URL
|
||||
<ftp://ftp.uu.net/graphics/png/documents/zlib/zdoc-index.html>.
|
||||
|
||||
Abstract
|
||||
|
||||
This specification defines a lossless compressed data format. The
|
||||
data can be produced or consumed, even for an arbitrarily long
|
||||
sequentially presented input data stream, using only an a priori
|
||||
bounded amount of intermediate storage. The format presently uses
|
||||
the DEFLATE compression method but can be easily extended to use
|
||||
other compression methods. It can be implemented readily in a manner
|
||||
not covered by patents. This specification also defines the ADLER-32
|
||||
checksum (an extension and improvement of the Fletcher checksum),
|
||||
used for detection of data corruption, and provides an algorithm for
|
||||
computing it.
|
||||
|
||||
|
||||
|
||||
|
||||
Deutsch & Gailly Informational [Page 1]
|
||||
|
||||
RFC 1950 ZLIB Compressed Data Format Specification May 1996
|
||||
|
||||
|
||||
Table of Contents
|
||||
|
||||
1. Introduction ................................................... 2
|
||||
1.1. Purpose ................................................... 2
|
||||
1.2. Intended audience ......................................... 3
|
||||
1.3. Scope ..................................................... 3
|
||||
1.4. Compliance ................................................ 3
|
||||
1.5. Definitions of terms and conventions used ................ 3
|
||||
1.6. Changes from previous versions ............................ 3
|
||||
2. Detailed specification ......................................... 3
|
||||
2.1. Overall conventions ....................................... 3
|
||||
2.2. Data format ............................................... 4
|
||||
2.3. Compliance ................................................ 7
|
||||
3. References ..................................................... 7
|
||||
4. Source code .................................................... 8
|
||||
5. Security Considerations ........................................ 8
|
||||
6. Acknowledgements ............................................... 8
|
||||
7. Authors' Addresses ............................................. 8
|
||||
8. Appendix: Rationale ............................................ 9
|
||||
9. Appendix: Sample code ..........................................10
|
||||
|
||||
1. Introduction
|
||||
|
||||
1.1. Purpose
|
||||
|
||||
The purpose of this specification is to define a lossless
|
||||
compressed data format that:
|
||||
|
||||
* Is independent of CPU type, operating system, file system,
|
||||
and character set, and hence can be used for interchange;
|
||||
|
||||
* Can be produced or consumed, even for an arbitrarily long
|
||||
sequentially presented input data stream, using only an a
|
||||
priori bounded amount of intermediate storage, and hence can
|
||||
be used in data communications or similar structures such as
|
||||
Unix filters;
|
||||
|
||||
* Can use a number of different compression methods;
|
||||
|
||||
* Can be implemented readily in a manner not covered by
|
||||
patents, and hence can be practiced freely.
|
||||
|
||||
The data format defined by this specification does not attempt to
|
||||
allow random access to compressed data.
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
Deutsch & Gailly Informational [Page 2]
|
||||
|
||||
RFC 1950 ZLIB Compressed Data Format Specification May 1996
|
||||
|
||||
|
||||
1.2. Intended audience
|
||||
|
||||
This specification is intended for use by implementors of software
|
||||
to compress data into zlib format and/or decompress data from zlib
|
||||
format.
|
||||
|
||||
The text of the specification assumes a basic background in
|
||||
programming at the level of bits and other primitive data
|
||||
representations.
|
||||
|
||||
1.3. Scope
|
||||
|
||||
The specification specifies a compressed data format that can be
|
||||
used for in-memory compression of a sequence of arbitrary bytes.
|
||||
|
||||
1.4. Compliance
|
||||
|
||||
Unless otherwise indicated below, a compliant decompressor must be
|
||||
able to accept and decompress any data set that conforms to all
|
||||
the specifications presented here; a compliant compressor must
|
||||
produce data sets that conform to all the specifications presented
|
||||
here.
|
||||
|
||||
1.5. Definitions of terms and conventions used
|
||||
|
||||
byte: 8 bits stored or transmitted as a unit (same as an octet).
|
||||
(For this specification, a byte is exactly 8 bits, even on
|
||||
machines which store a character on a number of bits different
|
||||
from 8.) See below, for the numbering of bits within a byte.
|
||||
|
||||
1.6. Changes from previous versions
|
||||
|
||||
Version 3.1 was the first public release of this specification.
|
||||
In version 3.2, some terminology was changed and the Adler-32
|
||||
sample code was rewritten for clarity. In version 3.3, the
|
||||
support for a preset dictionary was introduced, and the
|
||||
specification was converted to RFC style.
|
||||
|
||||
2. Detailed specification
|
||||
|
||||
2.1. Overall conventions
|
||||
|
||||
In the diagrams below, a box like this:
|
||||
|
||||
+---+
|
||||
| | <-- the vertical bars might be missing
|
||||
+---+
|
||||
|
||||
|
||||
|
||||
|
||||
Deutsch & Gailly Informational [Page 3]
|
||||
|
||||
RFC 1950 ZLIB Compressed Data Format Specification May 1996
|
||||
|
||||
|
||||
represents one byte; a box like this:
|
||||
|
||||
+==============+
|
||||
| |
|
||||
+==============+
|
||||
|
||||
represents a variable number of bytes.
|
||||
|
||||
Bytes stored within a computer do not have a "bit order", since
|
||||
they are always treated as a unit. However, a byte considered as
|
||||
an integer between 0 and 255 does have a most- and least-
|
||||
significant bit, and since we write numbers with the most-
|
||||
significant digit on the left, we also write bytes with the most-
|
||||
significant bit on the left. In the diagrams below, we number the
|
||||
bits of a byte so that bit 0 is the least-significant bit, i.e.,
|
||||
the bits are numbered:
|
||||
|
||||
+--------+
|
||||
|76543210|
|
||||
+--------+
|
||||
|
||||
Within a computer, a number may occupy multiple bytes. All
|
||||
multi-byte numbers in the format described here are stored with
|
||||
the MOST-significant byte first (at the lower memory address).
|
||||
For example, the decimal number 520 is stored as:
|
||||
|
||||
0 1
|
||||
+--------+--------+
|
||||
|00000010|00001000|
|
||||
+--------+--------+
|
||||
^ ^
|
||||
| |
|
||||
| + less significant byte = 8
|
||||
+ more significant byte = 2 x 256
|
||||
|
||||
2.2. Data format
|
||||
|
||||
A zlib stream has the following structure:
|
||||
|
||||
0 1
|
||||
+---+---+
|
||||
|CMF|FLG| (more-->)
|
||||
+---+---+
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
Deutsch & Gailly Informational [Page 4]
|
||||
|
||||
RFC 1950 ZLIB Compressed Data Format Specification May 1996
|
||||
|
||||
|
||||
(if FLG.FDICT set)
|
||||
|
||||
0 1 2 3
|
||||
+---+---+---+---+
|
||||
| DICTID | (more-->)
|
||||
+---+---+---+---+
|
||||
|
||||
+=====================+---+---+---+---+
|
||||
|...compressed data...| ADLER32 |
|
||||
+=====================+---+---+---+---+
|
||||
|
||||
Any data which may appear after ADLER32 are not part of the zlib
|
||||
stream.
|
||||
|
||||
CMF (Compression Method and flags)
|
||||
This byte is divided into a 4-bit compression method and a 4-
|
||||
bit information field depending on the compression method.
|
||||
|
||||
bits 0 to 3 CM Compression method
|
||||
bits 4 to 7 CINFO Compression info
|
||||
|
||||
CM (Compression method)
|
||||
This identifies the compression method used in the file. CM = 8
|
||||
denotes the "deflate" compression method with a window size up
|
||||
to 32K. This is the method used by gzip and PNG (see
|
||||
references [1] and [2] in Chapter 3, below, for the reference
|
||||
documents). CM = 15 is reserved. It might be used in a future
|
||||
version of this specification to indicate the presence of an
|
||||
extra field before the compressed data.
|
||||
|
||||
CINFO (Compression info)
|
||||
For CM = 8, CINFO is the base-2 logarithm of the LZ77 window
|
||||
size, minus eight (CINFO=7 indicates a 32K window size). Values
|
||||
of CINFO above 7 are not allowed in this version of the
|
||||
specification. CINFO is not defined in this specification for
|
||||
CM not equal to 8.
|
||||
|
||||
FLG (FLaGs)
|
||||
This flag byte is divided as follows:
|
||||
|
||||
bits 0 to 4 FCHECK (check bits for CMF and FLG)
|
||||
bit 5 FDICT (preset dictionary)
|
||||
bits 6 to 7 FLEVEL (compression level)
|
||||
|
||||
The FCHECK value must be such that CMF and FLG, when viewed as
|
||||
a 16-bit unsigned integer stored in MSB order (CMF*256 + FLG),
|
||||
is a multiple of 31.
|
||||
|
||||
|
||||
|
||||
|
||||
Deutsch & Gailly Informational [Page 5]
|
||||
|
||||
RFC 1950 ZLIB Compressed Data Format Specification May 1996
|
||||
|
||||
|
||||
FDICT (Preset dictionary)
|
||||
If FDICT is set, a DICT dictionary identifier is present
|
||||
immediately after the FLG byte. The dictionary is a sequence of
|
||||
bytes which are initially fed to the compressor without
|
||||
producing any compressed output. DICT is the Adler-32 checksum
|
||||
of this sequence of bytes (see the definition of ADLER32
|
||||
below). The decompressor can use this identifier to determine
|
||||
which dictionary has been used by the compressor.
|
||||
|
||||
FLEVEL (Compression level)
|
||||
These flags are available for use by specific compression
|
||||
methods. The "deflate" method (CM = 8) sets these flags as
|
||||
follows:
|
||||
|
||||
0 - compressor used fastest algorithm
|
||||
1 - compressor used fast algorithm
|
||||
2 - compressor used default algorithm
|
||||
3 - compressor used maximum compression, slowest algorithm
|
||||
|
||||
The information in FLEVEL is not needed for decompression; it
|
||||
is there to indicate if recompression might be worthwhile.
|
||||
|
||||
compressed data
|
||||
For compression method 8, the compressed data is stored in the
|
||||
deflate compressed data format as described in the document
|
||||
"DEFLATE Compressed Data Format Specification" by L. Peter
|
||||
Deutsch. (See reference [3] in Chapter 3, below)
|
||||
|
||||
Other compressed data formats are not specified in this version
|
||||
of the zlib specification.
|
||||
|
||||
ADLER32 (Adler-32 checksum)
|
||||
This contains a checksum value of the uncompressed data
|
||||
(excluding any dictionary data) computed according to Adler-32
|
||||
algorithm. This algorithm is a 32-bit extension and improvement
|
||||
of the Fletcher algorithm, used in the ITU-T X.224 / ISO 8073
|
||||
standard. See references [4] and [5] in Chapter 3, below)
|
||||
|
||||
Adler-32 is composed of two sums accumulated per byte: s1 is
|
||||
the sum of all bytes, s2 is the sum of all s1 values. Both sums
|
||||
are done modulo 65521. s1 is initialized to 1, s2 to zero. The
|
||||
Adler-32 checksum is stored as s2*65536 + s1 in most-
|
||||
significant-byte first (network) order.
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
Deutsch & Gailly Informational [Page 6]
|
||||
|
||||
RFC 1950 ZLIB Compressed Data Format Specification May 1996
|
||||
|
||||
|
||||
2.3. Compliance
|
||||
|
||||
A compliant compressor must produce streams with correct CMF, FLG
|
||||
and ADLER32, but need not support preset dictionaries. When the
|
||||
zlib data format is used as part of another standard data format,
|
||||
the compressor may use only preset dictionaries that are specified
|
||||
by this other data format. If this other format does not use the
|
||||
preset dictionary feature, the compressor must not set the FDICT
|
||||
flag.
|
||||
|
||||
A compliant decompressor must check CMF, FLG, and ADLER32, and
|
||||
provide an error indication if any of these have incorrect values.
|
||||
A compliant decompressor must give an error indication if CM is
|
||||
not one of the values defined in this specification (only the
|
||||
value 8 is permitted in this version), since another value could
|
||||
indicate the presence of new features that would cause subsequent
|
||||
data to be interpreted incorrectly. A compliant decompressor must
|
||||
give an error indication if FDICT is set and DICTID is not the
|
||||
identifier of a known preset dictionary. A decompressor may
|
||||
ignore FLEVEL and still be compliant. When the zlib data format
|
||||
is being used as a part of another standard format, a compliant
|
||||
decompressor must support all the preset dictionaries specified by
|
||||
the other format. When the other format does not use the preset
|
||||
dictionary feature, a compliant decompressor must reject any
|
||||
stream in which the FDICT flag is set.
|
||||
|
||||
3. References
|
||||
|
||||
[1] Deutsch, L.P.,"GZIP Compressed Data Format Specification",
|
||||
available in ftp://ftp.uu.net/pub/archiving/zip/doc/
|
||||
|
||||
[2] Thomas Boutell, "PNG (Portable Network Graphics) specification",
|
||||
available in ftp://ftp.uu.net/graphics/png/documents/
|
||||
|
||||
[3] Deutsch, L.P.,"DEFLATE Compressed Data Format Specification",
|
||||
available in ftp://ftp.uu.net/pub/archiving/zip/doc/
|
||||
|
||||
[4] Fletcher, J. G., "An Arithmetic Checksum for Serial
|
||||
Transmissions," IEEE Transactions on Communications, Vol. COM-30,
|
||||
No. 1, January 1982, pp. 247-252.
|
||||
|
||||
[5] ITU-T Recommendation X.224, Annex D, "Checksum Algorithms,"
|
||||
November, 1993, pp. 144, 145. (Available from
|
||||
gopher://info.itu.ch). ITU-T X.244 is also the same as ISO 8073.
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
Deutsch & Gailly Informational [Page 7]
|
||||
|
||||
RFC 1950 ZLIB Compressed Data Format Specification May 1996
|
||||
|
||||
|
||||
4. Source code
|
||||
|
||||
Source code for a C language implementation of a "zlib" compliant
|
||||
library is available at ftp://ftp.uu.net/pub/archiving/zip/zlib/.
|
||||
|
||||
5. Security Considerations
|
||||
|
||||
A decoder that fails to check the ADLER32 checksum value may be
|
||||
subject to undetected data corruption.
|
||||
|
||||
6. Acknowledgements
|
||||
|
||||
Trademarks cited in this document are the property of their
|
||||
respective owners.
|
||||
|
||||
Jean-Loup Gailly and Mark Adler designed the zlib format and wrote
|
||||
the related software described in this specification. Glenn
|
||||
Randers-Pehrson converted this document to RFC and HTML format.
|
||||
|
||||
7. Authors' Addresses
|
||||
|
||||
L. Peter Deutsch
|
||||
Aladdin Enterprises
|
||||
203 Santa Margarita Ave.
|
||||
Menlo Park, CA 94025
|
||||
|
||||
Phone: (415) 322-0103 (AM only)
|
||||
FAX: (415) 322-1734
|
||||
EMail: <ghost@aladdin.com>
|
||||
|
||||
|
||||
Jean-Loup Gailly
|
||||
|
||||
EMail: <gzip@prep.ai.mit.edu>
|
||||
|
||||
Questions about the technical content of this specification can be
|
||||
sent by email to
|
||||
|
||||
Jean-Loup Gailly <gzip@prep.ai.mit.edu> and
|
||||
Mark Adler <madler@alumni.caltech.edu>
|
||||
|
||||
Editorial comments on this specification can be sent by email to
|
||||
|
||||
L. Peter Deutsch <ghost@aladdin.com> and
|
||||
Glenn Randers-Pehrson <randeg@alumni.rpi.edu>
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
Deutsch & Gailly Informational [Page 8]
|
||||
|
||||
RFC 1950 ZLIB Compressed Data Format Specification May 1996
|
||||
|
||||
|
||||
8. Appendix: Rationale
|
||||
|
||||
8.1. Preset dictionaries
|
||||
|
||||
A preset dictionary is specially useful to compress short input
|
||||
sequences. The compressor can take advantage of the dictionary
|
||||
context to encode the input in a more compact manner. The
|
||||
decompressor can be initialized with the appropriate context by
|
||||
virtually decompressing a compressed version of the dictionary
|
||||
without producing any output. However for certain compression
|
||||
algorithms such as the deflate algorithm this operation can be
|
||||
achieved without actually performing any decompression.
|
||||
|
||||
The compressor and the decompressor must use exactly the same
|
||||
dictionary. The dictionary may be fixed or may be chosen among a
|
||||
certain number of predefined dictionaries, according to the kind
|
||||
of input data. The decompressor can determine which dictionary has
|
||||
been chosen by the compressor by checking the dictionary
|
||||
identifier. This document does not specify the contents of
|
||||
predefined dictionaries, since the optimal dictionaries are
|
||||
application specific. Standard data formats using this feature of
|
||||
the zlib specification must precisely define the allowed
|
||||
dictionaries.
|
||||
|
||||
8.2. The Adler-32 algorithm
|
||||
|
||||
The Adler-32 algorithm is much faster than the CRC32 algorithm yet
|
||||
still provides an extremely low probability of undetected errors.
|
||||
|
||||
The modulo on unsigned long accumulators can be delayed for 5552
|
||||
bytes, so the modulo operation time is negligible. If the bytes
|
||||
are a, b, c, the second sum is 3a + 2b + c + 3, and so is position
|
||||
and order sensitive, unlike the first sum, which is just a
|
||||
checksum. That 65521 is prime is important to avoid a possible
|
||||
large class of two-byte errors that leave the check unchanged.
|
||||
(The Fletcher checksum uses 255, which is not prime and which also
|
||||
makes the Fletcher check insensitive to single byte changes 0 <->
|
||||
255.)
|
||||
|
||||
The sum s1 is initialized to 1 instead of zero to make the length
|
||||
of the sequence part of s2, so that the length does not have to be
|
||||
checked separately. (Any sequence of zeroes has a Fletcher
|
||||
checksum of zero.)
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
Deutsch & Gailly Informational [Page 9]
|
||||
|
||||
RFC 1950 ZLIB Compressed Data Format Specification May 1996
|
||||
|
||||
|
||||
9. Appendix: Sample code
|
||||
|
||||
The following C code computes the Adler-32 checksum of a data buffer.
|
||||
It is written for clarity, not for speed. The sample code is in the
|
||||
ANSI C programming language. Non C users may find it easier to read
|
||||
with these hints:
|
||||
|
||||
& Bitwise AND operator.
|
||||
>> Bitwise right shift operator. When applied to an
|
||||
unsigned quantity, as here, right shift inserts zero bit(s)
|
||||
at the left.
|
||||
<< Bitwise left shift operator. Left shift inserts zero
|
||||
bit(s) at the right.
|
||||
++ "n++" increments the variable n.
|
||||
% modulo operator: a % b is the remainder of a divided by b.
|
||||
|
||||
#define BASE 65521 /* largest prime smaller than 65536 */
|
||||
|
||||
/*
|
||||
Update a running Adler-32 checksum with the bytes buf[0..len-1]
|
||||
and return the updated checksum. The Adler-32 checksum should be
|
||||
initialized to 1.
|
||||
|
||||
Usage example:
|
||||
|
||||
unsigned long adler = 1L;
|
||||
|
||||
while (read_buffer(buffer, length) != EOF) {
|
||||
adler = update_adler32(adler, buffer, length);
|
||||
}
|
||||
if (adler != original_adler) error();
|
||||
*/
|
||||
unsigned long update_adler32(unsigned long adler,
|
||||
unsigned char *buf, int len)
|
||||
{
|
||||
unsigned long s1 = adler & 0xffff;
|
||||
unsigned long s2 = (adler >> 16) & 0xffff;
|
||||
int n;
|
||||
|
||||
for (n = 0; n < len; n++) {
|
||||
s1 = (s1 + buf[n]) % BASE;
|
||||
s2 = (s2 + s1) % BASE;
|
||||
}
|
||||
return (s2 << 16) + s1;
|
||||
}
|
||||
|
||||
/* Return the adler32 of the bytes buf[0..len-1] */
|
||||
|
||||
|
||||
|
||||
|
||||
Deutsch & Gailly Informational [Page 10]
|
||||
|
||||
RFC 1950 ZLIB Compressed Data Format Specification May 1996
|
||||
|
||||
|
||||
unsigned long adler32(unsigned char *buf, int len)
|
||||
{
|
||||
return update_adler32(1L, buf, len);
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
Deutsch & Gailly Informational [Page 11]
|
||||
|
955
lib/libz/doc/rfc1951.txt
Normal file
955
lib/libz/doc/rfc1951.txt
Normal file
@ -0,0 +1,955 @@
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
Network Working Group P. Deutsch
|
||||
Request for Comments: 1951 Aladdin Enterprises
|
||||
Category: Informational May 1996
|
||||
|
||||
|
||||
DEFLATE Compressed Data Format Specification version 1.3
|
||||
|
||||
Status of This Memo
|
||||
|
||||
This memo provides information for the Internet community. This memo
|
||||
does not specify an Internet standard of any kind. Distribution of
|
||||
this memo is unlimited.
|
||||
|
||||
IESG Note:
|
||||
|
||||
The IESG takes no position on the validity of any Intellectual
|
||||
Property Rights statements contained in this document.
|
||||
|
||||
Notices
|
||||
|
||||
Copyright (c) 1996 L. Peter Deutsch
|
||||
|
||||
Permission is granted to copy and distribute this document for any
|
||||
purpose and without charge, including translations into other
|
||||
languages and incorporation into compilations, provided that the
|
||||
copyright notice and this notice are preserved, and that any
|
||||
substantive changes or deletions from the original are clearly
|
||||
marked.
|
||||
|
||||
A pointer to the latest version of this and related documentation in
|
||||
HTML format can be found at the URL
|
||||
<ftp://ftp.uu.net/graphics/png/documents/zlib/zdoc-index.html>.
|
||||
|
||||
Abstract
|
||||
|
||||
This specification defines a lossless compressed data format that
|
||||
compresses data using a combination of the LZ77 algorithm and Huffman
|
||||
coding, with efficiency comparable to the best currently available
|
||||
general-purpose compression methods. The data can be produced or
|
||||
consumed, even for an arbitrarily long sequentially presented input
|
||||
data stream, using only an a priori bounded amount of intermediate
|
||||
storage. The format can be implemented readily in a manner not
|
||||
covered by patents.
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
Deutsch Informational [Page 1]
|
||||
|
||||
RFC 1951 DEFLATE Compressed Data Format Specification May 1996
|
||||
|
||||
|
||||
Table of Contents
|
||||
|
||||
1. Introduction ................................................... 2
|
||||
1.1. Purpose ................................................... 2
|
||||
1.2. Intended audience ......................................... 3
|
||||
1.3. Scope ..................................................... 3
|
||||
1.4. Compliance ................................................ 3
|
||||
1.5. Definitions of terms and conventions used ................ 3
|
||||
1.6. Changes from previous versions ............................ 4
|
||||
2. Compressed representation overview ............................. 4
|
||||
3. Detailed specification ......................................... 5
|
||||
3.1. Overall conventions ....................................... 5
|
||||
3.1.1. Packing into bytes .................................. 5
|
||||
3.2. Compressed block format ................................... 6
|
||||
3.2.1. Synopsis of prefix and Huffman coding ............... 6
|
||||
3.2.2. Use of Huffman coding in the "deflate" format ....... 7
|
||||
3.2.3. Details of block format ............................. 9
|
||||
3.2.4. Non-compressed blocks (BTYPE=00) ................... 11
|
||||
3.2.5. Compressed blocks (length and distance codes) ...... 11
|
||||
3.2.6. Compression with fixed Huffman codes (BTYPE=01) .... 12
|
||||
3.2.7. Compression with dynamic Huffman codes (BTYPE=10) .. 13
|
||||
3.3. Compliance ............................................... 14
|
||||
4. Compression algorithm details ................................. 14
|
||||
5. References .................................................... 16
|
||||
6. Security Considerations ....................................... 16
|
||||
7. Source code ................................................... 16
|
||||
8. Acknowledgements .............................................. 16
|
||||
9. Author's Address .............................................. 17
|
||||
|
||||
1. Introduction
|
||||
|
||||
1.1. Purpose
|
||||
|
||||
The purpose of this specification is to define a lossless
|
||||
compressed data format that:
|
||||
* Is independent of CPU type, operating system, file system,
|
||||
and character set, and hence can be used for interchange;
|
||||
* Can be produced or consumed, even for an arbitrarily long
|
||||
sequentially presented input data stream, using only an a
|
||||
priori bounded amount of intermediate storage, and hence
|
||||
can be used in data communications or similar structures
|
||||
such as Unix filters;
|
||||
* Compresses data with efficiency comparable to the best
|
||||
currently available general-purpose compression methods,
|
||||
and in particular considerably better than the "compress"
|
||||
program;
|
||||
* Can be implemented readily in a manner not covered by
|
||||
patents, and hence can be practiced freely;
|
||||
|
||||
|
||||
|
||||
Deutsch Informational [Page 2]
|
||||
|
||||
RFC 1951 DEFLATE Compressed Data Format Specification May 1996
|
||||
|
||||
|
||||
* Is compatible with the file format produced by the current
|
||||
widely used gzip utility, in that conforming decompressors
|
||||
will be able to read data produced by the existing gzip
|
||||
compressor.
|
||||
|
||||
The data format defined by this specification does not attempt to:
|
||||
|
||||
* Allow random access to compressed data;
|
||||
* Compress specialized data (e.g., raster graphics) as well
|
||||
as the best currently available specialized algorithms.
|
||||
|
||||
A simple counting argument shows that no lossless compression
|
||||
algorithm can compress every possible input data set. For the
|
||||
format defined here, the worst case expansion is 5 bytes per 32K-
|
||||
byte block, i.e., a size increase of 0.015% for large data sets.
|
||||
English text usually compresses by a factor of 2.5 to 3;
|
||||
executable files usually compress somewhat less; graphical data
|
||||
such as raster images may compress much more.
|
||||
|
||||
1.2. Intended audience
|
||||
|
||||
This specification is intended for use by implementors of software
|
||||
to compress data into "deflate" format and/or decompress data from
|
||||
"deflate" format.
|
||||
|
||||
The text of the specification assumes a basic background in
|
||||
programming at the level of bits and other primitive data
|
||||
representations. Familiarity with the technique of Huffman coding
|
||||
is helpful but not required.
|
||||
|
||||
1.3. Scope
|
||||
|
||||
The specification specifies a method for representing a sequence
|
||||
of bytes as a (usually shorter) sequence of bits, and a method for
|
||||
packing the latter bit sequence into bytes.
|
||||
|
||||
1.4. Compliance
|
||||
|
||||
Unless otherwise indicated below, a compliant decompressor must be
|
||||
able to accept and decompress any data set that conforms to all
|
||||
the specifications presented here; a compliant compressor must
|
||||
produce data sets that conform to all the specifications presented
|
||||
here.
|
||||
|
||||
1.5. Definitions of terms and conventions used
|
||||
|
||||
Byte: 8 bits stored or transmitted as a unit (same as an octet).
|
||||
For this specification, a byte is exactly 8 bits, even on machines
|
||||
|
||||
|
||||
|
||||
Deutsch Informational [Page 3]
|
||||
|
||||
RFC 1951 DEFLATE Compressed Data Format Specification May 1996
|
||||
|
||||
|
||||
which store a character on a number of bits different from eight.
|
||||
See below, for the numbering of bits within a byte.
|
||||
|
||||
String: a sequence of arbitrary bytes.
|
||||
|
||||
1.6. Changes from previous versions
|
||||
|
||||
There have been no technical changes to the deflate format since
|
||||
version 1.1 of this specification. In version 1.2, some
|
||||
terminology was changed. Version 1.3 is a conversion of the
|
||||
specification to RFC style.
|
||||
|
||||
2. Compressed representation overview
|
||||
|
||||
A compressed data set consists of a series of blocks, corresponding
|
||||
to successive blocks of input data. The block sizes are arbitrary,
|
||||
except that non-compressible blocks are limited to 65,535 bytes.
|
||||
|
||||
Each block is compressed using a combination of the LZ77 algorithm
|
||||
and Huffman coding. The Huffman trees for each block are independent
|
||||
of those for previous or subsequent blocks; the LZ77 algorithm may
|
||||
use a reference to a duplicated string occurring in a previous block,
|
||||
up to 32K input bytes before.
|
||||
|
||||
Each block consists of two parts: a pair of Huffman code trees that
|
||||
describe the representation of the compressed data part, and a
|
||||
compressed data part. (The Huffman trees themselves are compressed
|
||||
using Huffman encoding.) The compressed data consists of a series of
|
||||
elements of two types: literal bytes (of strings that have not been
|
||||
detected as duplicated within the previous 32K input bytes), and
|
||||
pointers to duplicated strings, where a pointer is represented as a
|
||||
pair <length, backward distance>. The representation used in the
|
||||
"deflate" format limits distances to 32K bytes and lengths to 258
|
||||
bytes, but does not limit the size of a block, except for
|
||||
uncompressible blocks, which are limited as noted above.
|
||||
|
||||
Each type of value (literals, distances, and lengths) in the
|
||||
compressed data is represented using a Huffman code, using one code
|
||||
tree for literals and lengths and a separate code tree for distances.
|
||||
The code trees for each block appear in a compact form just before
|
||||
the compressed data for that block.
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
Deutsch Informational [Page 4]
|
||||
|
||||
RFC 1951 DEFLATE Compressed Data Format Specification May 1996
|
||||
|
||||
|
||||
3. Detailed specification
|
||||
|
||||
3.1. Overall conventions In the diagrams below, a box like this:
|
||||
|
||||
+---+
|
||||
| | <-- the vertical bars might be missing
|
||||
+---+
|
||||
|
||||
represents one byte; a box like this:
|
||||
|
||||
+==============+
|
||||
| |
|
||||
+==============+
|
||||
|
||||
represents a variable number of bytes.
|
||||
|
||||
Bytes stored within a computer do not have a "bit order", since
|
||||
they are always treated as a unit. However, a byte considered as
|
||||
an integer between 0 and 255 does have a most- and least-
|
||||
significant bit, and since we write numbers with the most-
|
||||
significant digit on the left, we also write bytes with the most-
|
||||
significant bit on the left. In the diagrams below, we number the
|
||||
bits of a byte so that bit 0 is the least-significant bit, i.e.,
|
||||
the bits are numbered:
|
||||
|
||||
+--------+
|
||||
|76543210|
|
||||
+--------+
|
||||
|
||||
Within a computer, a number may occupy multiple bytes. All
|
||||
multi-byte numbers in the format described here are stored with
|
||||
the least-significant byte first (at the lower memory address).
|
||||
For example, the decimal number 520 is stored as:
|
||||
|
||||
0 1
|
||||
+--------+--------+
|
||||
|00001000|00000010|
|
||||
+--------+--------+
|
||||
^ ^
|
||||
| |
|
||||
| + more significant byte = 2 x 256
|
||||
+ less significant byte = 8
|
||||
|
||||
3.1.1. Packing into bytes
|
||||
|
||||
This document does not address the issue of the order in which
|
||||
bits of a byte are transmitted on a bit-sequential medium,
|
||||
since the final data format described here is byte- rather than
|
||||
|
||||
|
||||
|
||||
Deutsch Informational [Page 5]
|
||||
|
||||
RFC 1951 DEFLATE Compressed Data Format Specification May 1996
|
||||
|
||||
|
||||
bit-oriented. However, we describe the compressed block format
|
||||
in below, as a sequence of data elements of various bit
|
||||
lengths, not a sequence of bytes. We must therefore specify
|
||||
how to pack these data elements into bytes to form the final
|
||||
compressed byte sequence:
|
||||
|
||||
* Data elements are packed into bytes in order of
|
||||
increasing bit number within the byte, i.e., starting
|
||||
with the least-significant bit of the byte.
|
||||
* Data elements other than Huffman codes are packed
|
||||
starting with the least-significant bit of the data
|
||||
element.
|
||||
* Huffman codes are packed starting with the most-
|
||||
significant bit of the code.
|
||||
|
||||
In other words, if one were to print out the compressed data as
|
||||
a sequence of bytes, starting with the first byte at the
|
||||
*right* margin and proceeding to the *left*, with the most-
|
||||
significant bit of each byte on the left as usual, one would be
|
||||
able to parse the result from right to left, with fixed-width
|
||||
elements in the correct MSB-to-LSB order and Huffman codes in
|
||||
bit-reversed order (i.e., with the first bit of the code in the
|
||||
relative LSB position).
|
||||
|
||||
3.2. Compressed block format
|
||||
|
||||
3.2.1. Synopsis of prefix and Huffman coding
|
||||
|
||||
Prefix coding represents symbols from an a priori known
|
||||
alphabet by bit sequences (codes), one code for each symbol, in
|
||||
a manner such that different symbols may be represented by bit
|
||||
sequences of different lengths, but a parser can always parse
|
||||
an encoded string unambiguously symbol-by-symbol.
|
||||
|
||||
We define a prefix code in terms of a binary tree in which the
|
||||
two edges descending from each non-leaf node are labeled 0 and
|
||||
1 and in which the leaf nodes correspond one-for-one with (are
|
||||
labeled with) the symbols of the alphabet; then the code for a
|
||||
symbol is the sequence of 0's and 1's on the edges leading from
|
||||
the root to the leaf labeled with that symbol. For example:
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
Deutsch Informational [Page 6]
|
||||
|
||||
RFC 1951 DEFLATE Compressed Data Format Specification May 1996
|
||||
|
||||
|
||||
/\ Symbol Code
|
||||
0 1 ------ ----
|
||||
/ \ A 00
|
||||
/\ B B 1
|
||||
0 1 C 011
|
||||
/ \ D 010
|
||||
A /\
|
||||
0 1
|
||||
/ \
|
||||
D C
|
||||
|
||||
A parser can decode the next symbol from an encoded input
|
||||
stream by walking down the tree from the root, at each step
|
||||
choosing the edge corresponding to the next input bit.
|
||||
|
||||
Given an alphabet with known symbol frequencies, the Huffman
|
||||
algorithm allows the construction of an optimal prefix code
|
||||
(one which represents strings with those symbol frequencies
|
||||
using the fewest bits of any possible prefix codes for that
|
||||
alphabet). Such a code is called a Huffman code. (See
|
||||
reference [1] in Chapter 5, references for additional
|
||||
information on Huffman codes.)
|
||||
|
||||
Note that in the "deflate" format, the Huffman codes for the
|
||||
various alphabets must not exceed certain maximum code lengths.
|
||||
This constraint complicates the algorithm for computing code
|
||||
lengths from symbol frequencies. Again, see Chapter 5,
|
||||
references for details.
|
||||
|
||||
3.2.2. Use of Huffman coding in the "deflate" format
|
||||
|
||||
The Huffman codes used for each alphabet in the "deflate"
|
||||
format have two additional rules:
|
||||
|
||||
* All codes of a given bit length have lexicographically
|
||||
consecutive values, in the same order as the symbols
|
||||
they represent;
|
||||
|
||||
* Shorter codes lexicographically precede longer codes.
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
Deutsch Informational [Page 7]
|
||||
|
||||
RFC 1951 DEFLATE Compressed Data Format Specification May 1996
|
||||
|
||||
|
||||
We could recode the example above to follow this rule as
|
||||
follows, assuming that the order of the alphabet is ABCD:
|
||||
|
||||
Symbol Code
|
||||
------ ----
|
||||
A 10
|
||||
B 0
|
||||
C 110
|
||||
D 111
|
||||
|
||||
I.e., 0 precedes 10 which precedes 11x, and 110 and 111 are
|
||||
lexicographically consecutive.
|
||||
|
||||
Given this rule, we can define the Huffman code for an alphabet
|
||||
just by giving the bit lengths of the codes for each symbol of
|
||||
the alphabet in order; this is sufficient to determine the
|
||||
actual codes. In our example, the code is completely defined
|
||||
by the sequence of bit lengths (2, 1, 3, 3). The following
|
||||
algorithm generates the codes as integers, intended to be read
|
||||
from most- to least-significant bit. The code lengths are
|
||||
initially in tree[I].Len; the codes are produced in
|
||||
tree[I].Code.
|
||||
|
||||
1) Count the number of codes for each code length. Let
|
||||
bl_count[N] be the number of codes of length N, N >= 1.
|
||||
|
||||
2) Find the numerical value of the smallest code for each
|
||||
code length:
|
||||
|
||||
code = 0;
|
||||
bl_count[0] = 0;
|
||||
for (bits = 1; bits <= MAX_BITS; bits++) {
|
||||
code = (code + bl_count[bits-1]) << 1;
|
||||
next_code[bits] = code;
|
||||
}
|
||||
|
||||
3) Assign numerical values to all codes, using consecutive
|
||||
values for all codes of the same length with the base
|
||||
values determined at step 2. Codes that are never used
|
||||
(which have a bit length of zero) must not be assigned a
|
||||
value.
|
||||
|
||||
for (n = 0; n <= max_code; n++) {
|
||||
len = tree[n].Len;
|
||||
if (len != 0) {
|
||||
tree[n].Code = next_code[len];
|
||||
next_code[len]++;
|
||||
}
|
||||
|
||||
|
||||
|
||||
Deutsch Informational [Page 8]
|
||||
|
||||
RFC 1951 DEFLATE Compressed Data Format Specification May 1996
|
||||
|
||||
|
||||
}
|
||||
|
||||
Example:
|
||||
|
||||
Consider the alphabet ABCDEFGH, with bit lengths (3, 3, 3, 3,
|
||||
3, 2, 4, 4). After step 1, we have:
|
||||
|
||||
N bl_count[N]
|
||||
- -----------
|
||||
2 1
|
||||
3 5
|
||||
4 2
|
||||
|
||||
Step 2 computes the following next_code values:
|
||||
|
||||
N next_code[N]
|
||||
- ------------
|
||||
1 0
|
||||
2 0
|
||||
3 2
|
||||
4 14
|
||||
|
||||
Step 3 produces the following code values:
|
||||
|
||||
Symbol Length Code
|
||||
------ ------ ----
|
||||
A 3 010
|
||||
B 3 011
|
||||
C 3 100
|
||||
D 3 101
|
||||
E 3 110
|
||||
F 2 00
|
||||
G 4 1110
|
||||
H 4 1111
|
||||
|
||||
3.2.3. Details of block format
|
||||
|
||||
Each block of compressed data begins with 3 header bits
|
||||
containing the following data:
|
||||
|
||||
first bit BFINAL
|
||||
next 2 bits BTYPE
|
||||
|
||||
Note that the header bits do not necessarily begin on a byte
|
||||
boundary, since a block does not necessarily occupy an integral
|
||||
number of bytes.
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
Deutsch Informational [Page 9]
|
||||
|
||||
RFC 1951 DEFLATE Compressed Data Format Specification May 1996
|
||||
|
||||
|
||||
BFINAL is set if and only if this is the last block of the data
|
||||
set.
|
||||
|
||||
BTYPE specifies how the data are compressed, as follows:
|
||||
|
||||
00 - no compression
|
||||
01 - compressed with fixed Huffman codes
|
||||
10 - compressed with dynamic Huffman codes
|
||||
11 - reserved (error)
|
||||
|
||||
The only difference between the two compressed cases is how the
|
||||
Huffman codes for the literal/length and distance alphabets are
|
||||
defined.
|
||||
|
||||
In all cases, the decoding algorithm for the actual data is as
|
||||
follows:
|
||||
|
||||
do
|
||||
read block header from input stream.
|
||||
if stored with no compression
|
||||
skip any remaining bits in current partially
|
||||
processed byte
|
||||
read LEN and NLEN (see next section)
|
||||
copy LEN bytes of data to output
|
||||
otherwise
|
||||
if compressed with dynamic Huffman codes
|
||||
read representation of code trees (see
|
||||
subsection below)
|
||||
loop (until end of block code recognized)
|
||||
decode literal/length value from input stream
|
||||
if value < 256
|
||||
copy value (literal byte) to output stream
|
||||
otherwise
|
||||
if value = end of block (256)
|
||||
break from loop
|
||||
otherwise (value = 257..285)
|
||||
decode distance from input stream
|
||||
|
||||
move backwards distance bytes in the output
|
||||
stream, and copy length bytes from this
|
||||
position to the output stream.
|
||||
end loop
|
||||
while not last block
|
||||
|
||||
Note that a duplicated string reference may refer to a string
|
||||
in a previous block; i.e., the backward distance may cross one
|
||||
or more block boundaries. However a distance cannot refer past
|
||||
the beginning of the output stream. (An application using a
|
||||
|
||||
|
||||
|
||||
Deutsch Informational [Page 10]
|
||||
|
||||
RFC 1951 DEFLATE Compressed Data Format Specification May 1996
|
||||
|
||||
|
||||
preset dictionary might discard part of the output stream; a
|
||||
distance can refer to that part of the output stream anyway)
|
||||
Note also that the referenced string may overlap the current
|
||||
position; for example, if the last 2 bytes decoded have values
|
||||
X and Y, a string reference with <length = 5, distance = 2>
|
||||
adds X,Y,X,Y,X to the output stream.
|
||||
|
||||
We now specify each compression method in turn.
|
||||
|
||||
3.2.4. Non-compressed blocks (BTYPE=00)
|
||||
|
||||
Any bits of input up to the next byte boundary are ignored.
|
||||
The rest of the block consists of the following information:
|
||||
|
||||
0 1 2 3 4...
|
||||
+---+---+---+---+================================+
|
||||
| LEN | NLEN |... LEN bytes of literal data...|
|
||||
+---+---+---+---+================================+
|
||||
|
||||
LEN is the number of data bytes in the block. NLEN is the
|
||||
one's complement of LEN.
|
||||
|
||||
3.2.5. Compressed blocks (length and distance codes)
|
||||
|
||||
As noted above, encoded data blocks in the "deflate" format
|
||||
consist of sequences of symbols drawn from three conceptually
|
||||
distinct alphabets: either literal bytes, from the alphabet of
|
||||
byte values (0..255), or <length, backward distance> pairs,
|
||||
where the length is drawn from (3..258) and the distance is
|
||||
drawn from (1..32,768). In fact, the literal and length
|
||||
alphabets are merged into a single alphabet (0..285), where
|
||||
values 0..255 represent literal bytes, the value 256 indicates
|
||||
end-of-block, and values 257..285 represent length codes
|
||||
(possibly in conjunction with extra bits following the symbol
|
||||
code) as follows:
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
Deutsch Informational [Page 11]
|
||||
|
||||
RFC 1951 DEFLATE Compressed Data Format Specification May 1996
|
||||
|
||||
|
||||
Extra Extra Extra
|
||||
Code Bits Length(s) Code Bits Lengths Code Bits Length(s)
|
||||
---- ---- ------ ---- ---- ------- ---- ---- -------
|
||||
257 0 3 267 1 15,16 277 4 67-82
|
||||
258 0 4 268 1 17,18 278 4 83-98
|
||||
259 0 5 269 2 19-22 279 4 99-114
|
||||
260 0 6 270 2 23-26 280 4 115-130
|
||||
261 0 7 271 2 27-30 281 5 131-162
|
||||
262 0 8 272 2 31-34 282 5 163-194
|
||||
263 0 9 273 3 35-42 283 5 195-226
|
||||
264 0 10 274 3 43-50 284 5 227-257
|
||||
265 1 11,12 275 3 51-58 285 0 258
|
||||
266 1 13,14 276 3 59-66
|
||||
|
||||
The extra bits should be interpreted as a machine integer
|
||||
stored with the most-significant bit first, e.g., bits 1110
|
||||
represent the value 14.
|
||||
|
||||
Extra Extra Extra
|
||||
Code Bits Dist Code Bits Dist Code Bits Distance
|
||||
---- ---- ---- ---- ---- ------ ---- ---- --------
|
||||
0 0 1 10 4 33-48 20 9 1025-1536
|
||||
1 0 2 11 4 49-64 21 9 1537-2048
|
||||
2 0 3 12 5 65-96 22 10 2049-3072
|
||||
3 0 4 13 5 97-128 23 10 3073-4096
|
||||
4 1 5,6 14 6 129-192 24 11 4097-6144
|
||||
5 1 7,8 15 6 193-256 25 11 6145-8192
|
||||
6 2 9-12 16 7 257-384 26 12 8193-12288
|
||||
7 2 13-16 17 7 385-512 27 12 12289-16384
|
||||
8 3 17-24 18 8 513-768 28 13 16385-24576
|
||||
9 3 25-32 19 8 769-1024 29 13 24577-32768
|
||||
|
||||
3.2.6. Compression with fixed Huffman codes (BTYPE=01)
|
||||
|
||||
The Huffman codes for the two alphabets are fixed, and are not
|
||||
represented explicitly in the data. The Huffman code lengths
|
||||
for the literal/length alphabet are:
|
||||
|
||||
Lit Value Bits Codes
|
||||
--------- ---- -----
|
||||
0 - 143 8 00110000 through
|
||||
10111111
|
||||
144 - 255 9 110010000 through
|
||||
111111111
|
||||
256 - 279 7 0000000 through
|
||||
0010111
|
||||
280 - 287 8 11000000 through
|
||||
11000111
|
||||
|
||||
|
||||
|
||||
Deutsch Informational [Page 12]
|
||||
|
||||
RFC 1951 DEFLATE Compressed Data Format Specification May 1996
|
||||
|
||||
|
||||
The code lengths are sufficient to generate the actual codes,
|
||||
as described above; we show the codes in the table for added
|
||||
clarity. Literal/length values 286-287 will never actually
|
||||
occur in the compressed data, but participate in the code
|
||||
construction.
|
||||
|
||||
Distance codes 0-31 are represented by (fixed-length) 5-bit
|
||||
codes, with possible additional bits as shown in the table
|
||||
shown in Paragraph 3.2.5, above. Note that distance codes 30-
|
||||
31 will never actually occur in the compressed data.
|
||||
|
||||
3.2.7. Compression with dynamic Huffman codes (BTYPE=10)
|
||||
|
||||
The Huffman codes for the two alphabets appear in the block
|
||||
immediately after the header bits and before the actual
|
||||
compressed data, first the literal/length code and then the
|
||||
distance code. Each code is defined by a sequence of code
|
||||
lengths, as discussed in Paragraph 3.2.2, above. For even
|
||||
greater compactness, the code length sequences themselves are
|
||||
compressed using a Huffman code. The alphabet for code lengths
|
||||
is as follows:
|
||||
|
||||
0 - 15: Represent code lengths of 0 - 15
|
||||
16: Copy the previous code length 3 - 6 times.
|
||||
The next 2 bits indicate repeat length
|
||||
(0 = 3, ... , 3 = 6)
|
||||
Example: Codes 8, 16 (+2 bits 11),
|
||||
16 (+2 bits 10) will expand to
|
||||
12 code lengths of 8 (1 + 6 + 5)
|
||||
17: Repeat a code length of 0 for 3 - 10 times.
|
||||
(3 bits of length)
|
||||
18: Repeat a code length of 0 for 11 - 138 times
|
||||
(7 bits of length)
|
||||
|
||||
A code length of 0 indicates that the corresponding symbol in
|
||||
the literal/length or distance alphabet will not occur in the
|
||||
block, and should not participate in the Huffman code
|
||||
construction algorithm given earlier. If only one distance
|
||||
code is used, it is encoded using one bit, not zero bits; in
|
||||
this case there is a single code length of one, with one unused
|
||||
code. One distance code of zero bits means that there are no
|
||||
distance codes used at all (the data is all literals).
|
||||
|
||||
We can now define the format of the block:
|
||||
|
||||
5 Bits: HLIT, # of Literal/Length codes - 257 (257 - 286)
|
||||
5 Bits: HDIST, # of Distance codes - 1 (1 - 32)
|
||||
4 Bits: HCLEN, # of Code Length codes - 4 (4 - 19)
|
||||
|
||||
|
||||
|
||||
Deutsch Informational [Page 13]
|
||||
|
||||
RFC 1951 DEFLATE Compressed Data Format Specification May 1996
|
||||
|
||||
|
||||
(HCLEN + 4) x 3 bits: code lengths for the code length
|
||||
alphabet given just above, in the order: 16, 17, 18,
|
||||
0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15
|
||||
|
||||
These code lengths are interpreted as 3-bit integers
|
||||
(0-7); as above, a code length of 0 means the
|
||||
corresponding symbol (literal/length or distance code
|
||||
length) is not used.
|
||||
|
||||
HLIT + 257 code lengths for the literal/length alphabet,
|
||||
encoded using the code length Huffman code
|
||||
|
||||
HDIST + 1 code lengths for the distance alphabet,
|
||||
encoded using the code length Huffman code
|
||||
|
||||
The actual compressed data of the block,
|
||||
encoded using the literal/length and distance Huffman
|
||||
codes
|
||||
|
||||
The literal/length symbol 256 (end of data),
|
||||
encoded using the literal/length Huffman code
|
||||
|
||||
The code length repeat codes can cross from HLIT + 257 to the
|
||||
HDIST + 1 code lengths. In other words, all code lengths form
|
||||
a single sequence of HLIT + HDIST + 258 values.
|
||||
|
||||
3.3. Compliance
|
||||
|
||||
A compressor may limit further the ranges of values specified in
|
||||
the previous section and still be compliant; for example, it may
|
||||
limit the range of backward pointers to some value smaller than
|
||||
32K. Similarly, a compressor may limit the size of blocks so that
|
||||
a compressible block fits in memory.
|
||||
|
||||
A compliant decompressor must accept the full range of possible
|
||||
values defined in the previous section, and must accept blocks of
|
||||
arbitrary size.
|
||||
|
||||
4. Compression algorithm details
|
||||
|
||||
While it is the intent of this document to define the "deflate"
|
||||
compressed data format without reference to any particular
|
||||
compression algorithm, the format is related to the compressed
|
||||
formats produced by LZ77 (Lempel-Ziv 1977, see reference [2] below);
|
||||
since many variations of LZ77 are patented, it is strongly
|
||||
recommended that the implementor of a compressor follow the general
|
||||
algorithm presented here, which is known not to be patented per se.
|
||||
The material in this section is not part of the definition of the
|
||||
|
||||
|
||||
|
||||
Deutsch Informational [Page 14]
|
||||
|
||||
RFC 1951 DEFLATE Compressed Data Format Specification May 1996
|
||||
|
||||
|
||||
specification per se, and a compressor need not follow it in order to
|
||||
be compliant.
|
||||
|
||||
The compressor terminates a block when it determines that starting a
|
||||
new block with fresh trees would be useful, or when the block size
|
||||
fills up the compressor's block buffer.
|
||||
|
||||
The compressor uses a chained hash table to find duplicated strings,
|
||||
using a hash function that operates on 3-byte sequences. At any
|
||||
given point during compression, let XYZ be the next 3 input bytes to
|
||||
be examined (not necessarily all different, of course). First, the
|
||||
compressor examines the hash chain for XYZ. If the chain is empty,
|
||||
the compressor simply writes out X as a literal byte and advances one
|
||||
byte in the input. If the hash chain is not empty, indicating that
|
||||
the sequence XYZ (or, if we are unlucky, some other 3 bytes with the
|
||||
same hash function value) has occurred recently, the compressor
|
||||
compares all strings on the XYZ hash chain with the actual input data
|
||||
sequence starting at the current point, and selects the longest
|
||||
match.
|
||||
|
||||
The compressor searches the hash chains starting with the most recent
|
||||
strings, to favor small distances and thus take advantage of the
|
||||
Huffman encoding. The hash chains are singly linked. There are no
|
||||
deletions from the hash chains; the algorithm simply discards matches
|
||||
that are too old. To avoid a worst-case situation, very long hash
|
||||
chains are arbitrarily truncated at a certain length, determined by a
|
||||
run-time parameter.
|
||||
|
||||
To improve overall compression, the compressor optionally defers the
|
||||
selection of matches ("lazy matching"): after a match of length N has
|
||||
been found, the compressor searches for a longer match starting at
|
||||
the next input byte. If it finds a longer match, it truncates the
|
||||
previous match to a length of one (thus producing a single literal
|
||||
byte) and then emits the longer match. Otherwise, it emits the
|
||||
original match, and, as described above, advances N bytes before
|
||||
continuing.
|
||||
|
||||
Run-time parameters also control this "lazy match" procedure. If
|
||||
compression ratio is most important, the compressor attempts a
|
||||
complete second search regardless of the length of the first match.
|
||||
In the normal case, if the current match is "long enough", the
|
||||
compressor reduces the search for a longer match, thus speeding up
|
||||
the process. If speed is most important, the compressor inserts new
|
||||
strings in the hash table only when no match was found, or when the
|
||||
match is not "too long". This degrades the compression ratio but
|
||||
saves time since there are both fewer insertions and fewer searches.
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
Deutsch Informational [Page 15]
|
||||
|
||||
RFC 1951 DEFLATE Compressed Data Format Specification May 1996
|
||||
|
||||
|
||||
5. References
|
||||
|
||||
[1] Huffman, D. A., "A Method for the Construction of Minimum
|
||||
Redundancy Codes", Proceedings of the Institute of Radio
|
||||
Engineers, September 1952, Volume 40, Number 9, pp. 1098-1101.
|
||||
|
||||
[2] Ziv J., Lempel A., "A Universal Algorithm for Sequential Data
|
||||
Compression", IEEE Transactions on Information Theory, Vol. 23,
|
||||
No. 3, pp. 337-343.
|
||||
|
||||
[3] Gailly, J.-L., and Adler, M., ZLIB documentation and sources,
|
||||
available in ftp://ftp.uu.net/pub/archiving/zip/doc/
|
||||
|
||||
[4] Gailly, J.-L., and Adler, M., GZIP documentation and sources,
|
||||
available as gzip-*.tar in ftp://prep.ai.mit.edu/pub/gnu/
|
||||
|
||||
[5] Schwartz, E. S., and Kallick, B. "Generating a canonical prefix
|
||||
encoding." Comm. ACM, 7,3 (Mar. 1964), pp. 166-169.
|
||||
|
||||
[6] Hirschberg and Lelewer, "Efficient decoding of prefix codes,"
|
||||
Comm. ACM, 33,4, April 1990, pp. 449-459.
|
||||
|
||||
6. Security Considerations
|
||||
|
||||
Any data compression method involves the reduction of redundancy in
|
||||
the data. Consequently, any corruption of the data is likely to have
|
||||
severe effects and be difficult to correct. Uncompressed text, on
|
||||
the other hand, will probably still be readable despite the presence
|
||||
of some corrupted bytes.
|
||||
|
||||
It is recommended that systems using this data format provide some
|
||||
means of validating the integrity of the compressed data. See
|
||||
reference [3], for example.
|
||||
|
||||
7. Source code
|
||||
|
||||
Source code for a C language implementation of a "deflate" compliant
|
||||
compressor and decompressor is available within the zlib package at
|
||||
ftp://ftp.uu.net/pub/archiving/zip/zlib/.
|
||||
|
||||
8. Acknowledgements
|
||||
|
||||
Trademarks cited in this document are the property of their
|
||||
respective owners.
|
||||
|
||||
Phil Katz designed the deflate format. Jean-Loup Gailly and Mark
|
||||
Adler wrote the related software described in this specification.
|
||||
Glenn Randers-Pehrson converted this document to RFC and HTML format.
|
||||
|
||||
|
||||
|
||||
Deutsch Informational [Page 16]
|
||||
|
||||
RFC 1951 DEFLATE Compressed Data Format Specification May 1996
|
||||
|
||||
|
||||
9. Author's Address
|
||||
|
||||
L. Peter Deutsch
|
||||
Aladdin Enterprises
|
||||
203 Santa Margarita Ave.
|
||||
Menlo Park, CA 94025
|
||||
|
||||
Phone: (415) 322-0103 (AM only)
|
||||
FAX: (415) 322-1734
|
||||
EMail: <ghost@aladdin.com>
|
||||
|
||||
Questions about the technical content of this specification can be
|
||||
sent by email to:
|
||||
|
||||
Jean-Loup Gailly <gzip@prep.ai.mit.edu> and
|
||||
Mark Adler <madler@alumni.caltech.edu>
|
||||
|
||||
Editorial comments on this specification can be sent by email to:
|
||||
|
||||
L. Peter Deutsch <ghost@aladdin.com> and
|
||||
Glenn Randers-Pehrson <randeg@alumni.rpi.edu>
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
Deutsch Informational [Page 17]
|
||||
|
675
lib/libz/doc/rfc1952.txt
Normal file
675
lib/libz/doc/rfc1952.txt
Normal file
@ -0,0 +1,675 @@
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
Network Working Group P. Deutsch
|
||||
Request for Comments: 1952 Aladdin Enterprises
|
||||
Category: Informational May 1996
|
||||
|
||||
|
||||
GZIP file format specification version 4.3
|
||||
|
||||
Status of This Memo
|
||||
|
||||
This memo provides information for the Internet community. This memo
|
||||
does not specify an Internet standard of any kind. Distribution of
|
||||
this memo is unlimited.
|
||||
|
||||
IESG Note:
|
||||
|
||||
The IESG takes no position on the validity of any Intellectual
|
||||
Property Rights statements contained in this document.
|
||||
|
||||
Notices
|
||||
|
||||
Copyright (c) 1996 L. Peter Deutsch
|
||||
|
||||
Permission is granted to copy and distribute this document for any
|
||||
purpose and without charge, including translations into other
|
||||
languages and incorporation into compilations, provided that the
|
||||
copyright notice and this notice are preserved, and that any
|
||||
substantive changes or deletions from the original are clearly
|
||||
marked.
|
||||
|
||||
A pointer to the latest version of this and related documentation in
|
||||
HTML format can be found at the URL
|
||||
<ftp://ftp.uu.net/graphics/png/documents/zlib/zdoc-index.html>.
|
||||
|
||||
Abstract
|
||||
|
||||
This specification defines a lossless compressed data format that is
|
||||
compatible with the widely used GZIP utility. The format includes a
|
||||
cyclic redundancy check value for detecting data corruption. The
|
||||
format presently uses the DEFLATE method of compression but can be
|
||||
easily extended to use other compression methods. The format can be
|
||||
implemented readily in a manner not covered by patents.
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
Deutsch Informational [Page 1]
|
||||
|
||||
RFC 1952 GZIP File Format Specification May 1996
|
||||
|
||||
|
||||
Table of Contents
|
||||
|
||||
1. Introduction ................................................... 2
|
||||
1.1. Purpose ................................................... 2
|
||||
1.2. Intended audience ......................................... 3
|
||||
1.3. Scope ..................................................... 3
|
||||
1.4. Compliance ................................................ 3
|
||||
1.5. Definitions of terms and conventions used ................. 3
|
||||
1.6. Changes from previous versions ............................ 3
|
||||
2. Detailed specification ......................................... 4
|
||||
2.1. Overall conventions ....................................... 4
|
||||
2.2. File format ............................................... 5
|
||||
2.3. Member format ............................................. 5
|
||||
2.3.1. Member header and trailer ........................... 6
|
||||
2.3.1.1. Extra field ................................... 8
|
||||
2.3.1.2. Compliance .................................... 9
|
||||
3. References .................................................. 9
|
||||
4. Security Considerations .................................... 10
|
||||
5. Acknowledgements ........................................... 10
|
||||
6. Author's Address ........................................... 10
|
||||
7. Appendix: Jean-Loup Gailly's gzip utility .................. 11
|
||||
8. Appendix: Sample CRC Code .................................. 11
|
||||
|
||||
1. Introduction
|
||||
|
||||
1.1. Purpose
|
||||
|
||||
The purpose of this specification is to define a lossless
|
||||
compressed data format that:
|
||||
|
||||
* Is independent of CPU type, operating system, file system,
|
||||
and character set, and hence can be used for interchange;
|
||||
* Can compress or decompress a data stream (as opposed to a
|
||||
randomly accessible file) to produce another data stream,
|
||||
using only an a priori bounded amount of intermediate
|
||||
storage, and hence can be used in data communications or
|
||||
similar structures such as Unix filters;
|
||||
* Compresses data with efficiency comparable to the best
|
||||
currently available general-purpose compression methods,
|
||||
and in particular considerably better than the "compress"
|
||||
program;
|
||||
* Can be implemented readily in a manner not covered by
|
||||
patents, and hence can be practiced freely;
|
||||
* Is compatible with the file format produced by the current
|
||||
widely used gzip utility, in that conforming decompressors
|
||||
will be able to read data produced by the existing gzip
|
||||
compressor.
|
||||
|
||||
|
||||
|
||||
|
||||
Deutsch Informational [Page 2]
|
||||
|
||||
RFC 1952 GZIP File Format Specification May 1996
|
||||
|
||||
|
||||
The data format defined by this specification does not attempt to:
|
||||
|
||||
* Provide random access to compressed data;
|
||||
* Compress specialized data (e.g., raster graphics) as well as
|
||||
the best currently available specialized algorithms.
|
||||
|
||||
1.2. Intended audience
|
||||
|
||||
This specification is intended for use by implementors of software
|
||||
to compress data into gzip format and/or decompress data from gzip
|
||||
format.
|
||||
|
||||
The text of the specification assumes a basic background in
|
||||
programming at the level of bits and other primitive data
|
||||
representations.
|
||||
|
||||
1.3. Scope
|
||||
|
||||
The specification specifies a compression method and a file format
|
||||
(the latter assuming only that a file can store a sequence of
|
||||
arbitrary bytes). It does not specify any particular interface to
|
||||
a file system or anything about character sets or encodings
|
||||
(except for file names and comments, which are optional).
|
||||
|
||||
1.4. Compliance
|
||||
|
||||
Unless otherwise indicated below, a compliant decompressor must be
|
||||
able to accept and decompress any file that conforms to all the
|
||||
specifications presented here; a compliant compressor must produce
|
||||
files that conform to all the specifications presented here. The
|
||||
material in the appendices is not part of the specification per se
|
||||
and is not relevant to compliance.
|
||||
|
||||
1.5. Definitions of terms and conventions used
|
||||
|
||||
byte: 8 bits stored or transmitted as a unit (same as an octet).
|
||||
(For this specification, a byte is exactly 8 bits, even on
|
||||
machines which store a character on a number of bits different
|
||||
from 8.) See below for the numbering of bits within a byte.
|
||||
|
||||
1.6. Changes from previous versions
|
||||
|
||||
There have been no technical changes to the gzip format since
|
||||
version 4.1 of this specification. In version 4.2, some
|
||||
terminology was changed, and the sample CRC code was rewritten for
|
||||
clarity and to eliminate the requirement for the caller to do pre-
|
||||
and post-conditioning. Version 4.3 is a conversion of the
|
||||
specification to RFC style.
|
||||
|
||||
|
||||
|
||||
Deutsch Informational [Page 3]
|
||||
|
||||
RFC 1952 GZIP File Format Specification May 1996
|
||||
|
||||
|
||||
2. Detailed specification
|
||||
|
||||
2.1. Overall conventions
|
||||
|
||||
In the diagrams below, a box like this:
|
||||
|
||||
+---+
|
||||
| | <-- the vertical bars might be missing
|
||||
+---+
|
||||
|
||||
represents one byte; a box like this:
|
||||
|
||||
+==============+
|
||||
| |
|
||||
+==============+
|
||||
|
||||
represents a variable number of bytes.
|
||||
|
||||
Bytes stored within a computer do not have a "bit order", since
|
||||
they are always treated as a unit. However, a byte considered as
|
||||
an integer between 0 and 255 does have a most- and least-
|
||||
significant bit, and since we write numbers with the most-
|
||||
significant digit on the left, we also write bytes with the most-
|
||||
significant bit on the left. In the diagrams below, we number the
|
||||
bits of a byte so that bit 0 is the least-significant bit, i.e.,
|
||||
the bits are numbered:
|
||||
|
||||
+--------+
|
||||
|76543210|
|
||||
+--------+
|
||||
|
||||
This document does not address the issue of the order in which
|
||||
bits of a byte are transmitted on a bit-sequential medium, since
|
||||
the data format described here is byte- rather than bit-oriented.
|
||||
|
||||
Within a computer, a number may occupy multiple bytes. All
|
||||
multi-byte numbers in the format described here are stored with
|
||||
the least-significant byte first (at the lower memory address).
|
||||
For example, the decimal number 520 is stored as:
|
||||
|
||||
0 1
|
||||
+--------+--------+
|
||||
|00001000|00000010|
|
||||
+--------+--------+
|
||||
^ ^
|
||||
| |
|
||||
| + more significant byte = 2 x 256
|
||||
+ less significant byte = 8
|
||||
|
||||
|
||||
|
||||
Deutsch Informational [Page 4]
|
||||
|
||||
RFC 1952 GZIP File Format Specification May 1996
|
||||
|
||||
|
||||
2.2. File format
|
||||
|
||||
A gzip file consists of a series of "members" (compressed data
|
||||
sets). The format of each member is specified in the following
|
||||
section. The members simply appear one after another in the file,
|
||||
with no additional information before, between, or after them.
|
||||
|
||||
2.3. Member format
|
||||
|
||||
Each member has the following structure:
|
||||
|
||||
+---+---+---+---+---+---+---+---+---+---+
|
||||
|ID1|ID2|CM |FLG| MTIME |XFL|OS | (more-->)
|
||||
+---+---+---+---+---+---+---+---+---+---+
|
||||
|
||||
(if FLG.FEXTRA set)
|
||||
|
||||
+---+---+=================================+
|
||||
| XLEN |...XLEN bytes of "extra field"...| (more-->)
|
||||
+---+---+=================================+
|
||||
|
||||
(if FLG.FNAME set)
|
||||
|
||||
+=========================================+
|
||||
|...original file name, zero-terminated...| (more-->)
|
||||
+=========================================+
|
||||
|
||||
(if FLG.FCOMMENT set)
|
||||
|
||||
+===================================+
|
||||
|...file comment, zero-terminated...| (more-->)
|
||||
+===================================+
|
||||
|
||||
(if FLG.FHCRC set)
|
||||
|
||||
+---+---+
|
||||
| CRC16 |
|
||||
+---+---+
|
||||
|
||||
+=======================+
|
||||
|...compressed blocks...| (more-->)
|
||||
+=======================+
|
||||
|
||||
0 1 2 3 4 5 6 7
|
||||
+---+---+---+---+---+---+---+---+
|
||||
| CRC32 | ISIZE |
|
||||
+---+---+---+---+---+---+---+---+
|
||||
|
||||
|
||||
|
||||
|
||||
Deutsch Informational [Page 5]
|
||||
|
||||
RFC 1952 GZIP File Format Specification May 1996
|
||||
|
||||
|
||||
2.3.1. Member header and trailer
|
||||
|
||||
ID1 (IDentification 1)
|
||||
ID2 (IDentification 2)
|
||||
These have the fixed values ID1 = 31 (0x1f, \037), ID2 = 139
|
||||
(0x8b, \213), to identify the file as being in gzip format.
|
||||
|
||||
CM (Compression Method)
|
||||
This identifies the compression method used in the file. CM
|
||||
= 0-7 are reserved. CM = 8 denotes the "deflate"
|
||||
compression method, which is the one customarily used by
|
||||
gzip and which is documented elsewhere.
|
||||
|
||||
FLG (FLaGs)
|
||||
This flag byte is divided into individual bits as follows:
|
||||
|
||||
bit 0 FTEXT
|
||||
bit 1 FHCRC
|
||||
bit 2 FEXTRA
|
||||
bit 3 FNAME
|
||||
bit 4 FCOMMENT
|
||||
bit 5 reserved
|
||||
bit 6 reserved
|
||||
bit 7 reserved
|
||||
|
||||
If FTEXT is set, the file is probably ASCII text. This is
|
||||
an optional indication, which the compressor may set by
|
||||
checking a small amount of the input data to see whether any
|
||||
non-ASCII characters are present. In case of doubt, FTEXT
|
||||
is cleared, indicating binary data. For systems which have
|
||||
different file formats for ascii text and binary data, the
|
||||
decompressor can use FTEXT to choose the appropriate format.
|
||||
We deliberately do not specify the algorithm used to set
|
||||
this bit, since a compressor always has the option of
|
||||
leaving it cleared and a decompressor always has the option
|
||||
of ignoring it and letting some other program handle issues
|
||||
of data conversion.
|
||||
|
||||
If FHCRC is set, a CRC16 for the gzip header is present,
|
||||
immediately before the compressed data. The CRC16 consists
|
||||
of the two least significant bytes of the CRC32 for all
|
||||
bytes of the gzip header up to and not including the CRC16.
|
||||
[The FHCRC bit was never set by versions of gzip up to
|
||||
1.2.4, even though it was documented with a different
|
||||
meaning in gzip 1.2.4.]
|
||||
|
||||
If FEXTRA is set, optional extra fields are present, as
|
||||
described in a following section.
|
||||
|
||||
|
||||
|
||||
Deutsch Informational [Page 6]
|
||||
|
||||
RFC 1952 GZIP File Format Specification May 1996
|
||||
|
||||
|
||||
If FNAME is set, an original file name is present,
|
||||
terminated by a zero byte. The name must consist of ISO
|
||||
8859-1 (LATIN-1) characters; on operating systems using
|
||||
EBCDIC or any other character set for file names, the name
|
||||
must be translated to the ISO LATIN-1 character set. This
|
||||
is the original name of the file being compressed, with any
|
||||
directory components removed, and, if the file being
|
||||
compressed is on a file system with case insensitive names,
|
||||
forced to lower case. There is no original file name if the
|
||||
data was compressed from a source other than a named file;
|
||||
for example, if the source was stdin on a Unix system, there
|
||||
is no file name.
|
||||
|
||||
If FCOMMENT is set, a zero-terminated file comment is
|
||||
present. This comment is not interpreted; it is only
|
||||
intended for human consumption. The comment must consist of
|
||||
ISO 8859-1 (LATIN-1) characters. Line breaks should be
|
||||
denoted by a single line feed character (10 decimal).
|
||||
|
||||
Reserved FLG bits must be zero.
|
||||
|
||||
MTIME (Modification TIME)
|
||||
This gives the most recent modification time of the original
|
||||
file being compressed. The time is in Unix format, i.e.,
|
||||
seconds since 00:00:00 GMT, Jan. 1, 1970. (Note that this
|
||||
may cause problems for MS-DOS and other systems that use
|
||||
local rather than Universal time.) If the compressed data
|
||||
did not come from a file, MTIME is set to the time at which
|
||||
compression started. MTIME = 0 means no time stamp is
|
||||
available.
|
||||
|
||||
XFL (eXtra FLags)
|
||||
These flags are available for use by specific compression
|
||||
methods. The "deflate" method (CM = 8) sets these flags as
|
||||
follows:
|
||||
|
||||
XFL = 2 - compressor used maximum compression,
|
||||
slowest algorithm
|
||||
XFL = 4 - compressor used fastest algorithm
|
||||
|
||||
OS (Operating System)
|
||||
This identifies the type of file system on which compression
|
||||
took place. This may be useful in determining end-of-line
|
||||
convention for text files. The currently defined values are
|
||||
as follows:
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
Deutsch Informational [Page 7]
|
||||
|
||||
RFC 1952 GZIP File Format Specification May 1996
|
||||
|
||||
|
||||
0 - FAT filesystem (MS-DOS, OS/2, NT/Win32)
|
||||
1 - Amiga
|
||||
2 - VMS (or OpenVMS)
|
||||
3 - Unix
|
||||
4 - VM/CMS
|
||||
5 - Atari TOS
|
||||
6 - HPFS filesystem (OS/2, NT)
|
||||
7 - Macintosh
|
||||
8 - Z-System
|
||||
9 - CP/M
|
||||
10 - TOPS-20
|
||||
11 - NTFS filesystem (NT)
|
||||
12 - QDOS
|
||||
13 - Acorn RISCOS
|
||||
255 - unknown
|
||||
|
||||
XLEN (eXtra LENgth)
|
||||
If FLG.FEXTRA is set, this gives the length of the optional
|
||||
extra field. See below for details.
|
||||
|
||||
CRC32 (CRC-32)
|
||||
This contains a Cyclic Redundancy Check value of the
|
||||
uncompressed data computed according to CRC-32 algorithm
|
||||
used in the ISO 3309 standard and in section 8.1.1.6.2 of
|
||||
ITU-T recommendation V.42. (See http://www.iso.ch for
|
||||
ordering ISO documents. See gopher://info.itu.ch for an
|
||||
online version of ITU-T V.42.)
|
||||
|
||||
ISIZE (Input SIZE)
|
||||
This contains the size of the original (uncompressed) input
|
||||
data modulo 2^32.
|
||||
|
||||
2.3.1.1. Extra field
|
||||
|
||||
If the FLG.FEXTRA bit is set, an "extra field" is present in
|
||||
the header, with total length XLEN bytes. It consists of a
|
||||
series of subfields, each of the form:
|
||||
|
||||
+---+---+---+---+==================================+
|
||||
|SI1|SI2| LEN |... LEN bytes of subfield data ...|
|
||||
+---+---+---+---+==================================+
|
||||
|
||||
SI1 and SI2 provide a subfield ID, typically two ASCII letters
|
||||
with some mnemonic value. Jean-Loup Gailly
|
||||
<gzip@prep.ai.mit.edu> is maintaining a registry of subfield
|
||||
IDs; please send him any subfield ID you wish to use. Subfield
|
||||
IDs with SI2 = 0 are reserved for future use. The following
|
||||
IDs are currently defined:
|
||||
|
||||
|
||||
|
||||
Deutsch Informational [Page 8]
|
||||
|
||||
RFC 1952 GZIP File Format Specification May 1996
|
||||
|
||||
|
||||
SI1 SI2 Data
|
||||
---------- ---------- ----
|
||||
0x41 ('A') 0x70 ('P') Apollo file type information
|
||||
|
||||
LEN gives the length of the subfield data, excluding the 4
|
||||
initial bytes.
|
||||
|
||||
2.3.1.2. Compliance
|
||||
|
||||
A compliant compressor must produce files with correct ID1,
|
||||
ID2, CM, CRC32, and ISIZE, but may set all the other fields in
|
||||
the fixed-length part of the header to default values (255 for
|
||||
OS, 0 for all others). The compressor must set all reserved
|
||||
bits to zero.
|
||||
|
||||
A compliant decompressor must check ID1, ID2, and CM, and
|
||||
provide an error indication if any of these have incorrect
|
||||
values. It must examine FEXTRA/XLEN, FNAME, FCOMMENT and FHCRC
|
||||
at least so it can skip over the optional fields if they are
|
||||
present. It need not examine any other part of the header or
|
||||
trailer; in particular, a decompressor may ignore FTEXT and OS
|
||||
and always produce binary output, and still be compliant. A
|
||||
compliant decompressor must give an error indication if any
|
||||
reserved bit is non-zero, since such a bit could indicate the
|
||||
presence of a new field that would cause subsequent data to be
|
||||
interpreted incorrectly.
|
||||
|
||||
3. References
|
||||
|
||||
[1] "Information Processing - 8-bit single-byte coded graphic
|
||||
character sets - Part 1: Latin alphabet No.1" (ISO 8859-1:1987).
|
||||
The ISO 8859-1 (Latin-1) character set is a superset of 7-bit
|
||||
ASCII. Files defining this character set are available as
|
||||
iso_8859-1.* in ftp://ftp.uu.net/graphics/png/documents/
|
||||
|
||||
[2] ISO 3309
|
||||
|
||||
[3] ITU-T recommendation V.42
|
||||
|
||||
[4] Deutsch, L.P.,"DEFLATE Compressed Data Format Specification",
|
||||
available in ftp://ftp.uu.net/pub/archiving/zip/doc/
|
||||
|
||||
[5] Gailly, J.-L., GZIP documentation, available as gzip-*.tar in
|
||||
ftp://prep.ai.mit.edu/pub/gnu/
|
||||
|
||||
[6] Sarwate, D.V., "Computation of Cyclic Redundancy Checks via Table
|
||||
Look-Up", Communications of the ACM, 31(8), pp.1008-1013.
|
||||
|
||||
|
||||
|
||||
|
||||
Deutsch Informational [Page 9]
|
||||
|
||||
RFC 1952 GZIP File Format Specification May 1996
|
||||
|
||||
|
||||
[7] Schwaderer, W.D., "CRC Calculation", April 85 PC Tech Journal,
|
||||
pp.118-133.
|
||||
|
||||
[8] ftp://ftp.adelaide.edu.au/pub/rocksoft/papers/crc_v3.txt,
|
||||
describing the CRC concept.
|
||||
|
||||
4. Security Considerations
|
||||
|
||||
Any data compression method involves the reduction of redundancy in
|
||||
the data. Consequently, any corruption of the data is likely to have
|
||||
severe effects and be difficult to correct. Uncompressed text, on
|
||||
the other hand, will probably still be readable despite the presence
|
||||
of some corrupted bytes.
|
||||
|
||||
It is recommended that systems using this data format provide some
|
||||
means of validating the integrity of the compressed data, such as by
|
||||
setting and checking the CRC-32 check value.
|
||||
|
||||
5. Acknowledgements
|
||||
|
||||
Trademarks cited in this document are the property of their
|
||||
respective owners.
|
||||
|
||||
Jean-Loup Gailly designed the gzip format and wrote, with Mark Adler,
|
||||
the related software described in this specification. Glenn
|
||||
Randers-Pehrson converted this document to RFC and HTML format.
|
||||
|
||||
6. Author's Address
|
||||
|
||||
L. Peter Deutsch
|
||||
Aladdin Enterprises
|
||||
203 Santa Margarita Ave.
|
||||
Menlo Park, CA 94025
|
||||
|
||||
Phone: (415) 322-0103 (AM only)
|
||||
FAX: (415) 322-1734
|
||||
EMail: <ghost@aladdin.com>
|
||||
|
||||
Questions about the technical content of this specification can be
|
||||
sent by email to:
|
||||
|
||||
Jean-Loup Gailly <gzip@prep.ai.mit.edu> and
|
||||
Mark Adler <madler@alumni.caltech.edu>
|
||||
|
||||
Editorial comments on this specification can be sent by email to:
|
||||
|
||||
L. Peter Deutsch <ghost@aladdin.com> and
|
||||
Glenn Randers-Pehrson <randeg@alumni.rpi.edu>
|
||||
|
||||
|
||||
|
||||
Deutsch Informational [Page 10]
|
||||
|
||||
RFC 1952 GZIP File Format Specification May 1996
|
||||
|
||||
|
||||
7. Appendix: Jean-Loup Gailly's gzip utility
|
||||
|
||||
The most widely used implementation of gzip compression, and the
|
||||
original documentation on which this specification is based, were
|
||||
created by Jean-Loup Gailly <gzip@prep.ai.mit.edu>. Since this
|
||||
implementation is a de facto standard, we mention some more of its
|
||||
features here. Again, the material in this section is not part of
|
||||
the specification per se, and implementations need not follow it to
|
||||
be compliant.
|
||||
|
||||
When compressing or decompressing a file, gzip preserves the
|
||||
protection, ownership, and modification time attributes on the local
|
||||
file system, since there is no provision for representing protection
|
||||
attributes in the gzip file format itself. Since the file format
|
||||
includes a modification time, the gzip decompressor provides a
|
||||
command line switch that assigns the modification time from the file,
|
||||
rather than the local modification time of the compressed input, to
|
||||
the decompressed output.
|
||||
|
||||
8. Appendix: Sample CRC Code
|
||||
|
||||
The following sample code represents a practical implementation of
|
||||
the CRC (Cyclic Redundancy Check). (See also ISO 3309 and ITU-T V.42
|
||||
for a formal specification.)
|
||||
|
||||
The sample code is in the ANSI C programming language. Non C users
|
||||
may find it easier to read with these hints:
|
||||
|
||||
& Bitwise AND operator.
|
||||
^ Bitwise exclusive-OR operator.
|
||||
>> Bitwise right shift operator. When applied to an
|
||||
unsigned quantity, as here, right shift inserts zero
|
||||
bit(s) at the left.
|
||||
! Logical NOT operator.
|
||||
++ "n++" increments the variable n.
|
||||
0xNNN 0x introduces a hexadecimal (base 16) constant.
|
||||
Suffix L indicates a long value (at least 32 bits).
|
||||
|
||||
/* Table of CRCs of all 8-bit messages. */
|
||||
unsigned long crc_table[256];
|
||||
|
||||
/* Flag: has the table been computed? Initially false. */
|
||||
int crc_table_computed = 0;
|
||||
|
||||
/* Make the table for a fast CRC. */
|
||||
void make_crc_table(void)
|
||||
{
|
||||
unsigned long c;
|
||||
|
||||
|
||||
|
||||
Deutsch Informational [Page 11]
|
||||
|
||||
RFC 1952 GZIP File Format Specification May 1996
|
||||
|
||||
|
||||
int n, k;
|
||||
for (n = 0; n < 256; n++) {
|
||||
c = (unsigned long) n;
|
||||
for (k = 0; k < 8; k++) {
|
||||
if (c & 1) {
|
||||
c = 0xedb88320L ^ (c >> 1);
|
||||
} else {
|
||||
c = c >> 1;
|
||||
}
|
||||
}
|
||||
crc_table[n] = c;
|
||||
}
|
||||
crc_table_computed = 1;
|
||||
}
|
||||
|
||||
/*
|
||||
Update a running crc with the bytes buf[0..len-1] and return
|
||||
the updated crc. The crc should be initialized to zero. Pre- and
|
||||
post-conditioning (one's complement) is performed within this
|
||||
function so it shouldn't be done by the caller. Usage example:
|
||||
|
||||
unsigned long crc = 0L;
|
||||
|
||||
while (read_buffer(buffer, length) != EOF) {
|
||||
crc = update_crc(crc, buffer, length);
|
||||
}
|
||||
if (crc != original_crc) error();
|
||||
*/
|
||||
unsigned long update_crc(unsigned long crc,
|
||||
unsigned char *buf, int len)
|
||||
{
|
||||
unsigned long c = crc ^ 0xffffffffL;
|
||||
int n;
|
||||
|
||||
if (!crc_table_computed)
|
||||
make_crc_table();
|
||||
for (n = 0; n < len; n++) {
|
||||
c = crc_table[(c ^ buf[n]) & 0xff] ^ (c >> 8);
|
||||
}
|
||||
return c ^ 0xffffffffL;
|
||||
}
|
||||
|
||||
/* Return the CRC of the bytes buf[0..len-1]. */
|
||||
unsigned long crc(unsigned char *buf, int len)
|
||||
{
|
||||
return update_crc(0L, buf, len);
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
Deutsch Informational [Page 12]
|
||||
|
107
lib/libz/doc/txtvsbin.txt
Normal file
107
lib/libz/doc/txtvsbin.txt
Normal file
@ -0,0 +1,107 @@
|
||||
A Fast Method for Identifying Plain Text Files
|
||||
==============================================
|
||||
|
||||
|
||||
Introduction
|
||||
------------
|
||||
|
||||
Given a file coming from an unknown source, it is sometimes desirable
|
||||
to find out whether the format of that file is plain text. Although
|
||||
this may appear like a simple task, a fully accurate detection of the
|
||||
file type requires heavy-duty semantic analysis on the file contents.
|
||||
It is, however, possible to obtain satisfactory results by employing
|
||||
various heuristics.
|
||||
|
||||
Previous versions of PKZip and other zip-compatible compression tools
|
||||
were using a crude detection scheme: if more than 80% (4/5) of the bytes
|
||||
found in a certain buffer are within the range [7..127], the file is
|
||||
labeled as plain text, otherwise it is labeled as binary. A prominent
|
||||
limitation of this scheme is the restriction to Latin-based alphabets.
|
||||
Other alphabets, like Greek, Cyrillic or Asian, make extensive use of
|
||||
the bytes within the range [128..255], and texts using these alphabets
|
||||
are most often misidentified by this scheme; in other words, the rate
|
||||
of false negatives is sometimes too high, which means that the recall
|
||||
is low. Another weakness of this scheme is a reduced precision, due to
|
||||
the false positives that may occur when binary files containing large
|
||||
amounts of textual characters are misidentified as plain text.
|
||||
|
||||
In this article we propose a new, simple detection scheme that features
|
||||
a much increased precision and a near-100% recall. This scheme is
|
||||
designed to work on ASCII, Unicode and other ASCII-derived alphabets,
|
||||
and it handles single-byte encodings (ISO-8859, MacRoman, KOI8, etc.)
|
||||
and variable-sized encodings (ISO-2022, UTF-8, etc.). Wider encodings
|
||||
(UCS-2/UTF-16 and UCS-4/UTF-32) are not handled, however.
|
||||
|
||||
|
||||
The Algorithm
|
||||
-------------
|
||||
|
||||
The algorithm works by dividing the set of bytecodes [0..255] into three
|
||||
categories:
|
||||
- The white list of textual bytecodes:
|
||||
9 (TAB), 10 (LF), 13 (CR), 32 (SPACE) to 255.
|
||||
- The gray list of tolerated bytecodes:
|
||||
7 (BEL), 8 (BS), 11 (VT), 12 (FF), 26 (SUB), 27 (ESC).
|
||||
- The black list of undesired, non-textual bytecodes:
|
||||
0 (NUL) to 6, 14 to 31.
|
||||
|
||||
If a file contains at least one byte that belongs to the white list and
|
||||
no byte that belongs to the black list, then the file is categorized as
|
||||
plain text; otherwise, it is categorized as binary. (The boundary case,
|
||||
when the file is empty, automatically falls into the latter category.)
|
||||
|
||||
|
||||
Rationale
|
||||
---------
|
||||
|
||||
The idea behind this algorithm relies on two observations.
|
||||
|
||||
The first observation is that, although the full range of 7-bit codes
|
||||
[0..127] is properly specified by the ASCII standard, most control
|
||||
characters in the range [0..31] are not used in practice. The only
|
||||
widely-used, almost universally-portable control codes are 9 (TAB),
|
||||
10 (LF) and 13 (CR). There are a few more control codes that are
|
||||
recognized on a reduced range of platforms and text viewers/editors:
|
||||
7 (BEL), 8 (BS), 11 (VT), 12 (FF), 26 (SUB) and 27 (ESC); but these
|
||||
codes are rarely (if ever) used alone, without being accompanied by
|
||||
some printable text. Even the newer, portable text formats such as
|
||||
XML avoid using control characters outside the list mentioned here.
|
||||
|
||||
The second observation is that most of the binary files tend to contain
|
||||
control characters, especially 0 (NUL). Even though the older text
|
||||
detection schemes observe the presence of non-ASCII codes from the range
|
||||
[128..255], the precision rarely has to suffer if this upper range is
|
||||
labeled as textual, because the files that are genuinely binary tend to
|
||||
contain both control characters and codes from the upper range. On the
|
||||
other hand, the upper range needs to be labeled as textual, because it
|
||||
is used by virtually all ASCII extensions. In particular, this range is
|
||||
used for encoding non-Latin scripts.
|
||||
|
||||
Since there is no counting involved, other than simply observing the
|
||||
presence or the absence of some byte values, the algorithm produces
|
||||
consistent results, regardless what alphabet encoding is being used.
|
||||
(If counting were involved, it could be possible to obtain different
|
||||
results on a text encoded, say, using ISO-8859-16 versus UTF-8.)
|
||||
|
||||
There is an extra category of plain text files that are "polluted" with
|
||||
one or more black-listed codes, either by mistake or by peculiar design
|
||||
considerations. In such cases, a scheme that tolerates a small fraction
|
||||
of black-listed codes would provide an increased recall (i.e. more true
|
||||
positives). This, however, incurs a reduced precision overall, since
|
||||
false positives are more likely to appear in binary files that contain
|
||||
large chunks of textual data. Furthermore, "polluted" plain text should
|
||||
be regarded as binary by general-purpose text detection schemes, because
|
||||
general-purpose text processing algorithms might not be applicable.
|
||||
Under this premise, it is safe to say that our detection method provides
|
||||
a near-100% recall.
|
||||
|
||||
Experiments have been run on many files coming from various platforms
|
||||
and applications. We tried plain text files, system logs, source code,
|
||||
formatted office documents, compiled object code, etc. The results
|
||||
confirm the optimistic assumptions about the capabilities of this
|
||||
algorithm.
|
||||
|
||||
|
||||
--
|
||||
Cosmin Truta
|
||||
Last updated: 2006-May-28
|
@ -1,12 +1,12 @@
|
||||
/* example.c -- usage example of the zlib compression library
|
||||
* Copyright (C) 1995-2004 Jean-loup Gailly.
|
||||
* Copyright (C) 1995-2006 Jean-loup Gailly.
|
||||
* For conditions of distribution and use, see copyright notice in zlib.h
|
||||
*/
|
||||
|
||||
/* @(#) $Id$ */
|
||||
|
||||
#include <stdio.h>
|
||||
#include "zlib.h"
|
||||
#include <stdio.h>
|
||||
|
||||
#ifdef STDC
|
||||
# include <string.h>
|
||||
|
25
lib/libz/gzclose.c
Normal file
25
lib/libz/gzclose.c
Normal file
@ -0,0 +1,25 @@
|
||||
/* gzclose.c -- zlib gzclose() function
|
||||
* Copyright (C) 2004, 2010 Mark Adler
|
||||
* For conditions of distribution and use, see copyright notice in zlib.h
|
||||
*/
|
||||
|
||||
#include "gzguts.h"
|
||||
|
||||
/* gzclose() is in a separate file so that it is linked in only if it is used.
|
||||
That way the other gzclose functions can be used instead to avoid linking in
|
||||
unneeded compression or decompression routines. */
|
||||
int ZEXPORT gzclose(file)
|
||||
gzFile file;
|
||||
{
|
||||
#ifndef NO_GZCOMPRESS
|
||||
gz_statep state;
|
||||
|
||||
if (file == NULL)
|
||||
return Z_STREAM_ERROR;
|
||||
state = (gz_statep)file;
|
||||
|
||||
return state->mode == GZ_READ ? gzclose_r(file) : gzclose_w(file);
|
||||
#else
|
||||
return gzclose_r(file);
|
||||
#endif
|
||||
}
|
132
lib/libz/gzguts.h
Normal file
132
lib/libz/gzguts.h
Normal file
@ -0,0 +1,132 @@
|
||||
/* gzguts.h -- zlib internal header definitions for gz* operations
|
||||
* Copyright (C) 2004, 2005, 2010 Mark Adler
|
||||
* For conditions of distribution and use, see copyright notice in zlib.h
|
||||
*/
|
||||
|
||||
#ifdef _LARGEFILE64_SOURCE
|
||||
# ifndef _LARGEFILE_SOURCE
|
||||
# define _LARGEFILE_SOURCE
|
||||
# endif
|
||||
# ifdef _FILE_OFFSET_BITS
|
||||
# undef _FILE_OFFSET_BITS
|
||||
# endif
|
||||
#endif
|
||||
|
||||
#define ZLIB_INTERNAL
|
||||
|
||||
#include <stdio.h>
|
||||
#include "zlib.h"
|
||||
#ifdef STDC
|
||||
# include <string.h>
|
||||
# include <stdlib.h>
|
||||
# include <limits.h>
|
||||
#endif
|
||||
#include <fcntl.h>
|
||||
|
||||
#ifdef NO_DEFLATE /* for compatibility with old definition */
|
||||
# define NO_GZCOMPRESS
|
||||
#endif
|
||||
|
||||
#ifdef _MSC_VER
|
||||
# include <io.h>
|
||||
# define vsnprintf _vsnprintf
|
||||
#endif
|
||||
|
||||
#ifndef local
|
||||
# define local static
|
||||
#endif
|
||||
/* compile with -Dlocal if your debugger can't find static symbols */
|
||||
|
||||
/* gz* functions always use library allocation functions */
|
||||
#ifndef STDC
|
||||
extern voidp malloc OF((uInt size));
|
||||
extern void free OF((voidpf ptr));
|
||||
#endif
|
||||
|
||||
/* get errno and strerror definition */
|
||||
#if defined UNDER_CE && defined NO_ERRNO_H
|
||||
# include <windows.h>
|
||||
# define zstrerror() gz_strwinerror((DWORD)GetLastError())
|
||||
#else
|
||||
# ifdef STDC
|
||||
# include <errno.h>
|
||||
# define zstrerror() strerror(errno)
|
||||
# else
|
||||
# define zstrerror() "stdio error (consult errno)"
|
||||
# endif
|
||||
#endif
|
||||
|
||||
/* MVS fdopen() */
|
||||
#ifdef __MVS__
|
||||
#pragma map (fdopen , "\174\174FDOPEN")
|
||||
FILE *fdopen(int, const char *);
|
||||
#endif
|
||||
|
||||
#ifdef _LARGEFILE64_SOURCE
|
||||
# define z_off64_t off64_t
|
||||
#else
|
||||
# define z_off64_t z_off_t
|
||||
#endif
|
||||
|
||||
/* default i/o buffer size -- double this for output when reading */
|
||||
#define GZBUFSIZE 8192
|
||||
|
||||
/* gzip modes, also provide a little integrity check on the passed structure */
|
||||
#define GZ_NONE 0
|
||||
#define GZ_READ 7247
|
||||
#define GZ_WRITE 31153
|
||||
#define GZ_APPEND 1 /* mode set to GZ_WRITE after the file is opened */
|
||||
|
||||
/* values for gz_state how */
|
||||
#define LOOK 0 /* look for a gzip header */
|
||||
#define COPY 1 /* copy input directly */
|
||||
#define GZIP 2 /* decompress a gzip stream */
|
||||
|
||||
/* internal gzip file state data structure */
|
||||
typedef struct {
|
||||
/* used for both reading and writing */
|
||||
int mode; /* see gzip modes above */
|
||||
int fd; /* file descriptor */
|
||||
char *path; /* path or fd for error messages */
|
||||
z_off64_t pos; /* current position in uncompressed data */
|
||||
unsigned size; /* buffer size, zero if not allocated yet */
|
||||
unsigned want; /* requested buffer size, default is GZBUFSIZE */
|
||||
unsigned char *in; /* input buffer */
|
||||
unsigned char *out; /* output buffer (double-sized when reading) */
|
||||
unsigned char *next; /* next output data to deliver or write */
|
||||
/* just for reading */
|
||||
unsigned have; /* amount of output data unused at next */
|
||||
int eof; /* true if end of input file reached */
|
||||
z_off64_t start; /* where the gzip data started, for rewinding */
|
||||
z_off64_t raw; /* where the raw data started, for seeking */
|
||||
int how; /* 0: get header, 1: copy, 2: decompress */
|
||||
int direct; /* true if last read direct, false if gzip */
|
||||
/* just for writing */
|
||||
int level; /* compression level */
|
||||
int strategy; /* compression strategy */
|
||||
/* seek request */
|
||||
z_off64_t skip; /* amount to skip (already rewound if backwards) */
|
||||
int seek; /* true if seek request pending */
|
||||
/* error information */
|
||||
int err; /* error code */
|
||||
char *msg; /* error message */
|
||||
/* zlib inflate or deflate stream */
|
||||
z_stream strm; /* stream structure in-place (not a pointer) */
|
||||
} gz_state;
|
||||
typedef gz_state FAR *gz_statep;
|
||||
|
||||
/* shared functions */
|
||||
ZEXTERN void ZEXPORT gz_error OF((gz_statep, int, const char *));
|
||||
#if defined UNDER_CE && defined NO_ERRNO_H
|
||||
ZEXTERN char ZEXPORT *gz_strwinerror OF((DWORD error));
|
||||
#endif
|
||||
|
||||
/* GT_OFF(x), where x is an unsigned value, is true if x > maximum z_off64_t
|
||||
value -- needed when comparing unsigned to z_off64_t, which is signed
|
||||
(possible z_off64_t types off_t, off64_t, and long are all signed) */
|
||||
#ifdef INT_MAX
|
||||
# define GT_OFF(x) (sizeof(int) == sizeof(z_off64_t) && (x) > INT_MAX)
|
||||
#else
|
||||
ZEXTERN unsigned ZEXPORT gz_intmax OF((void));
|
||||
# define GT_OFF(x) (sizeof(int) == sizeof(z_off64_t) && (x) > gz_intmax())
|
||||
#endif
|
1027
lib/libz/gzio.c
1027
lib/libz/gzio.c
File diff suppressed because it is too large
Load Diff
535
lib/libz/gzlib.c
Normal file
535
lib/libz/gzlib.c
Normal file
@ -0,0 +1,535 @@
|
||||
/* gzlib.c -- zlib functions common to reading and writing gzip files
|
||||
* Copyright (C) 2004, 2010 Mark Adler
|
||||
* For conditions of distribution and use, see copyright notice in zlib.h
|
||||
*/
|
||||
|
||||
#include "gzguts.h"
|
||||
|
||||
#ifdef _LARGEFILE64_SOURCE
|
||||
# define LSEEK lseek64
|
||||
#else
|
||||
# define LSEEK lseek
|
||||
#endif
|
||||
|
||||
/* Local functions */
|
||||
local void gz_reset OF((gz_statep));
|
||||
local gzFile gz_open OF((const char *, int, const char *));
|
||||
|
||||
#if defined UNDER_CE && defined NO_ERRNO_H
|
||||
|
||||
/* Map the Windows error number in ERROR to a locale-dependent error message
|
||||
string and return a pointer to it. Typically, the values for ERROR come
|
||||
from GetLastError.
|
||||
|
||||
The string pointed to shall not be modified by the application, but may be
|
||||
overwritten by a subsequent call to gz_strwinerror
|
||||
|
||||
The gz_strwinerror function does not change the current setting of
|
||||
GetLastError. */
|
||||
char ZEXPORT *gz_strwinerror (error)
|
||||
DWORD error;
|
||||
{
|
||||
static char buf[1024];
|
||||
|
||||
wchar_t *msgbuf;
|
||||
DWORD lasterr = GetLastError();
|
||||
DWORD chars = FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM
|
||||
| FORMAT_MESSAGE_ALLOCATE_BUFFER,
|
||||
NULL,
|
||||
error,
|
||||
0, /* Default language */
|
||||
(LPVOID)&msgbuf,
|
||||
0,
|
||||
NULL);
|
||||
if (chars != 0) {
|
||||
/* If there is an \r\n appended, zap it. */
|
||||
if (chars >= 2
|
||||
&& msgbuf[chars - 2] == '\r' && msgbuf[chars - 1] == '\n') {
|
||||
chars -= 2;
|
||||
msgbuf[chars] = 0;
|
||||
}
|
||||
|
||||
if (chars > sizeof (buf) - 1) {
|
||||
chars = sizeof (buf) - 1;
|
||||
msgbuf[chars] = 0;
|
||||
}
|
||||
|
||||
wcstombs(buf, msgbuf, chars + 1);
|
||||
LocalFree(msgbuf);
|
||||
}
|
||||
else {
|
||||
sprintf(buf, "unknown win32 error (%ld)", error);
|
||||
}
|
||||
|
||||
SetLastError(lasterr);
|
||||
return buf;
|
||||
}
|
||||
|
||||
#endif /* UNDER_CE && NO_ERRNO_H */
|
||||
|
||||
/* Reset gzip file state */
|
||||
local void gz_reset(state)
|
||||
gz_statep state;
|
||||
{
|
||||
if (state->mode == GZ_READ) { /* for reading ... */
|
||||
state->have = 0; /* no output data available */
|
||||
state->eof = 0; /* not at end of file */
|
||||
state->how = LOOK; /* look for gzip header */
|
||||
state->direct = 1; /* default for empty file */
|
||||
}
|
||||
state->seek = 0; /* no seek request pending */
|
||||
gz_error(state, Z_OK, NULL); /* clear error */
|
||||
state->pos = 0; /* no uncompressed data yet */
|
||||
state->strm.avail_in = 0; /* no input data yet */
|
||||
}
|
||||
|
||||
/* Open a gzip file either by name or file descriptor. */
|
||||
local gzFile gz_open(path, fd, mode)
|
||||
const char *path;
|
||||
int fd;
|
||||
const char *mode;
|
||||
{
|
||||
gz_statep state;
|
||||
|
||||
/* allocate gzFile structure to return */
|
||||
state = malloc(sizeof(gz_state));
|
||||
if (state == NULL)
|
||||
return NULL;
|
||||
state->size = 0; /* no buffers allocated yet */
|
||||
state->want = GZBUFSIZE; /* requested buffer size */
|
||||
state->msg = NULL; /* no error message yet */
|
||||
|
||||
/* interpret mode */
|
||||
state->mode = GZ_NONE;
|
||||
state->level = Z_DEFAULT_COMPRESSION;
|
||||
state->strategy = Z_DEFAULT_STRATEGY;
|
||||
while (*mode) {
|
||||
if (*mode >= '0' && *mode <= '9')
|
||||
state->level = *mode - '0';
|
||||
else
|
||||
switch (*mode) {
|
||||
case 'r':
|
||||
state->mode = GZ_READ;
|
||||
break;
|
||||
#ifndef NO_GZCOMPRESS
|
||||
case 'w':
|
||||
state->mode = GZ_WRITE;
|
||||
break;
|
||||
case 'a':
|
||||
state->mode = GZ_APPEND;
|
||||
break;
|
||||
#endif
|
||||
case '+': /* can't read and write at the same time */
|
||||
free(state);
|
||||
return NULL;
|
||||
case 'b': /* ignore -- will request binary anyway */
|
||||
break;
|
||||
case 'f':
|
||||
state->strategy = Z_FILTERED;
|
||||
break;
|
||||
case 'h':
|
||||
state->strategy = Z_HUFFMAN_ONLY;
|
||||
break;
|
||||
case 'R':
|
||||
state->strategy = Z_RLE;
|
||||
break;
|
||||
case 'F':
|
||||
state->strategy = Z_FIXED;
|
||||
default: /* could consider as an error, but just ignore */
|
||||
;
|
||||
}
|
||||
mode++;
|
||||
}
|
||||
|
||||
/* must provide an "r", "w", or "a" */
|
||||
if (state->mode == GZ_NONE) {
|
||||
free(state);
|
||||
return NULL;
|
||||
}
|
||||
|
||||
/* save the path name for error messages */
|
||||
state->path = malloc(strlen(path) + 1);
|
||||
if (state->path == NULL) {
|
||||
free(state);
|
||||
return NULL;
|
||||
}
|
||||
strcpy(state->path, path);
|
||||
|
||||
/* open the file with the appropriate mode (or just use fd) */
|
||||
state->fd = fd != -1 ? fd :
|
||||
open(path,
|
||||
#ifdef O_LARGEFILE
|
||||
O_LARGEFILE |
|
||||
#endif
|
||||
#ifdef O_BINARY
|
||||
O_BINARY |
|
||||
#endif
|
||||
(state->mode == GZ_READ ?
|
||||
O_RDONLY :
|
||||
(O_WRONLY | O_CREAT | (
|
||||
state->mode == GZ_WRITE ?
|
||||
O_TRUNC :
|
||||
O_APPEND))),
|
||||
0666);
|
||||
if (state->fd == -1) {
|
||||
free(state);
|
||||
return NULL;
|
||||
}
|
||||
if (state->mode == GZ_APPEND)
|
||||
state->mode = GZ_WRITE; /* simplify later checks */
|
||||
|
||||
/* save the current position for rewinding (only if reading) */
|
||||
if (state->mode == GZ_READ) {
|
||||
state->start = LSEEK(state->fd, 0, SEEK_CUR);
|
||||
if (state->start == -1) state->start = 0;
|
||||
}
|
||||
|
||||
/* initialize stream */
|
||||
gz_reset(state);
|
||||
|
||||
/* return stream */
|
||||
return (gzFile)state;
|
||||
}
|
||||
|
||||
/* -- see zlib.h -- */
|
||||
gzFile ZEXPORT gzopen(path, mode)
|
||||
const char *path;
|
||||
const char *mode;
|
||||
{
|
||||
return gz_open(path, -1, mode);
|
||||
}
|
||||
|
||||
/* -- see zlib.h -- */
|
||||
gzFile ZEXPORT gzopen64(path, mode)
|
||||
const char *path;
|
||||
const char *mode;
|
||||
{
|
||||
return gz_open(path, -1, mode);
|
||||
}
|
||||
|
||||
/* -- see zlib.h -- */
|
||||
gzFile ZEXPORT gzdopen(fd, mode)
|
||||
int fd;
|
||||
const char *mode;
|
||||
{
|
||||
char *path; /* identifier for error messages */
|
||||
gzFile gz;
|
||||
|
||||
if (fd == -1 || (path = malloc(7 + 3 * sizeof(int))) == NULL)
|
||||
return NULL;
|
||||
sprintf(path, "<fd:%d>", fd);
|
||||
gz = gz_open(path, fd, mode);
|
||||
free(path);
|
||||
return gz;
|
||||
}
|
||||
|
||||
/* -- see zlib.h -- */
|
||||
int ZEXPORT gzbuffer(file, size)
|
||||
gzFile file;
|
||||
unsigned size;
|
||||
{
|
||||
gz_statep state;
|
||||
|
||||
/* get internal structure and check integrity */
|
||||
if (file == NULL)
|
||||
return -1;
|
||||
state = (gz_statep)file;
|
||||
if (state->mode != GZ_READ && state->mode != GZ_WRITE)
|
||||
return -1;
|
||||
|
||||
/* make sure we haven't already allocated memory */
|
||||
if (state->size != 0)
|
||||
return -1;
|
||||
|
||||
/* check and set requested size */
|
||||
if (size == 0)
|
||||
return -1;
|
||||
state->want = size;
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* -- see zlib.h -- */
|
||||
int ZEXPORT gzrewind(file)
|
||||
gzFile file;
|
||||
{
|
||||
gz_statep state;
|
||||
|
||||
/* get internal structure */
|
||||
if (file == NULL)
|
||||
return -1;
|
||||
state = (gz_statep)file;
|
||||
|
||||
/* check that we're reading and that there's no error */
|
||||
if (state->mode != GZ_READ || state->err != Z_OK)
|
||||
return -1;
|
||||
|
||||
/* back up and start over */
|
||||
if (LSEEK(state->fd, state->start, SEEK_SET) == -1)
|
||||
return -1;
|
||||
gz_reset(state);
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* -- see zlib.h -- */
|
||||
z_off64_t ZEXPORT gzseek64(file, offset, whence)
|
||||
gzFile file;
|
||||
z_off64_t offset;
|
||||
int whence;
|
||||
{
|
||||
unsigned n;
|
||||
z_off64_t ret;
|
||||
gz_statep state;
|
||||
|
||||
/* get internal structure and check integrity */
|
||||
if (file == NULL)
|
||||
return -1;
|
||||
state = (gz_statep)file;
|
||||
if (state->mode != GZ_READ && state->mode != GZ_WRITE)
|
||||
return -1;
|
||||
|
||||
/* check that there's no error */
|
||||
if (state->err != Z_OK)
|
||||
return -1;
|
||||
|
||||
/* can only seek from start or relative to current position */
|
||||
if (whence != SEEK_SET && whence != SEEK_CUR)
|
||||
return -1;
|
||||
|
||||
/* normalize offset to a SEEK_CUR specification */
|
||||
if (whence == SEEK_SET)
|
||||
offset -= state->pos;
|
||||
else if (state->seek)
|
||||
offset += state->skip;
|
||||
state->seek = 0;
|
||||
|
||||
/* if within raw area while reading, just go there */
|
||||
if (state->mode == GZ_READ && state->how == COPY &&
|
||||
state->pos + offset >= state->raw) {
|
||||
ret = LSEEK(state->fd, offset, SEEK_CUR);
|
||||
if (ret == -1)
|
||||
return -1;
|
||||
state->have = 0;
|
||||
state->eof = 0;
|
||||
state->seek = 0;
|
||||
gz_error(state, Z_OK, NULL);
|
||||
state->strm.avail_in = 0;
|
||||
state->pos += offset;
|
||||
return state->pos;
|
||||
}
|
||||
|
||||
/* calculate skip amount, rewinding if needed for back seek when reading */
|
||||
if (offset < 0) {
|
||||
if (state->mode != GZ_READ) /* writing -- can't go backwards */
|
||||
return -1;
|
||||
offset += state->pos;
|
||||
if (offset < 0) /* before start of file! */
|
||||
return -1;
|
||||
if (gzrewind(file) == -1) /* rewind, then skip to offset */
|
||||
return -1;
|
||||
}
|
||||
|
||||
/* if reading, skip what's in output buffer (one less gzgetc() check) */
|
||||
if (state->mode == GZ_READ) {
|
||||
n = GT_OFF(state->have) || (z_off64_t)state->have > offset ?
|
||||
(unsigned)offset : state->have;
|
||||
state->have -= n;
|
||||
state->next += n;
|
||||
state->pos += n;
|
||||
offset -= n;
|
||||
}
|
||||
|
||||
/* request skip (if not zero) */
|
||||
if (offset) {
|
||||
state->seek = 1;
|
||||
state->skip = offset;
|
||||
}
|
||||
return state->pos + offset;
|
||||
}
|
||||
|
||||
/* -- see zlib.h -- */
|
||||
z_off_t ZEXPORT gzseek(file, offset, whence)
|
||||
gzFile file;
|
||||
z_off_t offset;
|
||||
int whence;
|
||||
{
|
||||
z_off64_t ret;
|
||||
|
||||
ret = gzseek64(file, (z_off64_t)offset, whence);
|
||||
return ret == (z_off_t)ret ? (z_off_t)ret : -1;
|
||||
}
|
||||
|
||||
/* -- see zlib.h -- */
|
||||
z_off64_t ZEXPORT gztell64(file)
|
||||
gzFile file;
|
||||
{
|
||||
gz_statep state;
|
||||
|
||||
/* get internal structure and check integrity */
|
||||
if (file == NULL)
|
||||
return -1;
|
||||
state = (gz_statep)file;
|
||||
if (state->mode != GZ_READ && state->mode != GZ_WRITE)
|
||||
return -1;
|
||||
|
||||
/* return position */
|
||||
return state->pos + (state->seek ? state->skip : 0);
|
||||
}
|
||||
|
||||
/* -- see zlib.h -- */
|
||||
z_off_t ZEXPORT gztell(file)
|
||||
gzFile file;
|
||||
{
|
||||
z_off64_t ret;
|
||||
|
||||
ret = gztell64(file);
|
||||
return ret == (z_off_t)ret ? (z_off_t)ret : -1;
|
||||
}
|
||||
|
||||
/* -- see zlib.h -- */
|
||||
z_off64_t ZEXPORT gzoffset64(file)
|
||||
gzFile file;
|
||||
{
|
||||
z_off64_t offset;
|
||||
gz_statep state;
|
||||
|
||||
/* get internal structure and check integrity */
|
||||
if (file == NULL)
|
||||
return -1;
|
||||
state = (gz_statep)file;
|
||||
if (state->mode != GZ_READ && state->mode != GZ_WRITE)
|
||||
return -1;
|
||||
|
||||
/* compute and return effective offset in file */
|
||||
offset = LSEEK(state->fd, 0, SEEK_CUR);
|
||||
if (offset == -1)
|
||||
return -1;
|
||||
if (state->mode == GZ_READ) /* reading */
|
||||
offset -= state->strm.avail_in; /* don't count buffered input */
|
||||
return offset;
|
||||
}
|
||||
|
||||
/* -- see zlib.h -- */
|
||||
z_off_t ZEXPORT gzoffset(file)
|
||||
gzFile file;
|
||||
{
|
||||
z_off64_t ret;
|
||||
|
||||
ret = gzoffset64(file);
|
||||
return ret == (z_off_t)ret ? (z_off_t)ret : -1;
|
||||
}
|
||||
|
||||
/* -- see zlib.h -- */
|
||||
int ZEXPORT gzeof(file)
|
||||
gzFile file;
|
||||
{
|
||||
gz_statep state;
|
||||
|
||||
/* get internal structure and check integrity */
|
||||
if (file == NULL)
|
||||
return 0;
|
||||
state = (gz_statep)file;
|
||||
if (state->mode != GZ_READ && state->mode != GZ_WRITE)
|
||||
return 0;
|
||||
|
||||
/* return end-of-file state */
|
||||
return state->mode == GZ_READ ? (state->eof && state->have == 0) : 0;
|
||||
}
|
||||
|
||||
/* -- see zlib.h -- */
|
||||
const char * ZEXPORT gzerror(file, errnum)
|
||||
gzFile file;
|
||||
int *errnum;
|
||||
{
|
||||
gz_statep state;
|
||||
|
||||
/* get internal structure and check integrity */
|
||||
if (file == NULL)
|
||||
return NULL;
|
||||
state = (gz_statep)file;
|
||||
if (state->mode != GZ_READ && state->mode != GZ_WRITE)
|
||||
return NULL;
|
||||
|
||||
/* return error information */
|
||||
if (errnum != NULL)
|
||||
*errnum = state->err;
|
||||
return state->msg == NULL ? "" : state->msg;
|
||||
}
|
||||
|
||||
/* -- see zlib.h -- */
|
||||
void ZEXPORT gzclearerr(file)
|
||||
gzFile file;
|
||||
{
|
||||
gz_statep state;
|
||||
|
||||
/* get internal structure and check integrity */
|
||||
if (file == NULL)
|
||||
return;
|
||||
state = (gz_statep)file;
|
||||
if (state->mode != GZ_READ && state->mode != GZ_WRITE)
|
||||
return;
|
||||
|
||||
/* clear error and end-of-file */
|
||||
if (state->mode == GZ_READ)
|
||||
state->eof = 0;
|
||||
gz_error(state, Z_OK, NULL);
|
||||
}
|
||||
|
||||
/* Create an error message in allocated memory and set state->err and
|
||||
state->msg accordingly. Free any previous error message already there. Do
|
||||
not try to free or allocate space if the error is Z_MEM_ERROR (out of
|
||||
memory). Simply save the error message as a static string. If there is an
|
||||
allocation failure constructing the error message, then convert the error to
|
||||
out of memory. */
|
||||
void ZEXPORT gz_error(state, err, msg)
|
||||
gz_statep state;
|
||||
int err;
|
||||
const char *msg;
|
||||
{
|
||||
/* free previously allocated message and clear */
|
||||
if (state->msg != NULL) {
|
||||
if (state->err != Z_MEM_ERROR)
|
||||
free(state->msg);
|
||||
state->msg = NULL;
|
||||
}
|
||||
|
||||
/* set error code, and if no message, then done */
|
||||
state->err = err;
|
||||
if (msg == NULL)
|
||||
return;
|
||||
|
||||
/* for an out of memory error, save as static string */
|
||||
if (err == Z_MEM_ERROR) {
|
||||
state->msg = (char *)msg;
|
||||
return;
|
||||
}
|
||||
|
||||
/* construct error message with path */
|
||||
if ((state->msg = malloc(strlen(state->path) + strlen(msg) + 3)) == NULL) {
|
||||
state->err = Z_MEM_ERROR;
|
||||
state->msg = (char *)"out of memory";
|
||||
return;
|
||||
}
|
||||
strcpy(state->msg, state->path);
|
||||
strcat(state->msg, ": ");
|
||||
strcat(state->msg, msg);
|
||||
return;
|
||||
}
|
||||
|
||||
#ifndef INT_MAX
|
||||
/* portably return maximum value for an int (when limits.h presumed not
|
||||
available) -- we need to do this to cover cases where 2's complement not
|
||||
used, since C standard permits 1's complement and sign-bit representations,
|
||||
otherwise we could just use ((unsigned)-1) >> 1 */
|
||||
unsigned ZEXPORT gz_intmax()
|
||||
{
|
||||
unsigned p, q;
|
||||
|
||||
p = 1;
|
||||
do {
|
||||
q = p;
|
||||
p <<= 1;
|
||||
p++;
|
||||
} while (p > q);
|
||||
return q >> 1;
|
||||
}
|
||||
#endif
|
653
lib/libz/gzread.c
Normal file
653
lib/libz/gzread.c
Normal file
@ -0,0 +1,653 @@
|
||||
/* gzread.c -- zlib functions for reading gzip files
|
||||
* Copyright (C) 2004, 2005, 2010 Mark Adler
|
||||
* For conditions of distribution and use, see copyright notice in zlib.h
|
||||
*/
|
||||
|
||||
#include "gzguts.h"
|
||||
#include <unistd.h>
|
||||
|
||||
/* Local functions */
|
||||
local int gz_load OF((gz_statep, unsigned char *, unsigned, unsigned *));
|
||||
local int gz_avail OF((gz_statep));
|
||||
local int gz_next4 OF((gz_statep, unsigned long *));
|
||||
local int gz_head OF((gz_statep));
|
||||
local int gz_decomp OF((gz_statep));
|
||||
local int gz_make OF((gz_statep));
|
||||
local int gz_skip OF((gz_statep, z_off64_t));
|
||||
|
||||
/* Use read() to load a buffer -- return -1 on error, otherwise 0. Read from
|
||||
state->fd, and update state->eof, state->err, and state->msg as appropriate.
|
||||
This function needs to loop on read(), since read() is not guaranteed to
|
||||
read the number of bytes requested, depending on the type of descriptor. */
|
||||
local int gz_load(state, buf, len, have)
|
||||
gz_statep state;
|
||||
unsigned char *buf;
|
||||
unsigned len;
|
||||
unsigned *have;
|
||||
{
|
||||
int ret;
|
||||
|
||||
*have = 0;
|
||||
do {
|
||||
ret = read(state->fd, buf + *have, len - *have);
|
||||
if (ret <= 0)
|
||||
break;
|
||||
*have += ret;
|
||||
} while (*have < len);
|
||||
if (ret < 0) {
|
||||
gz_error(state, Z_ERRNO, zstrerror());
|
||||
return -1;
|
||||
}
|
||||
if (ret == 0)
|
||||
state->eof = 1;
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* Load up input buffer and set eof flag if last data loaded -- return -1 on
|
||||
error, 0 otherwise. Note that the eof flag is set when the end of the input
|
||||
file is reached, even though there may be unused data in the buffer. Once
|
||||
that data has been used, no more attempts will be made to read the file.
|
||||
gz_avail() assumes that strm->avail_in == 0. */
|
||||
local int gz_avail(state)
|
||||
gz_statep state;
|
||||
{
|
||||
z_streamp strm = &(state->strm);
|
||||
|
||||
if (state->err != Z_OK)
|
||||
return -1;
|
||||
if (state->eof == 0) {
|
||||
if (gz_load(state, state->in, state->size, &(strm->avail_in)) == -1)
|
||||
return -1;
|
||||
strm->next_in = state->in;
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* Get next byte from input, or -1 if end or error. */
|
||||
#define NEXT() ((strm->avail_in == 0 && gz_avail(state) == -1) ? -1 : \
|
||||
(strm->avail_in == 0 ? -1 : \
|
||||
(strm->avail_in--, *(strm->next_in)++)))
|
||||
|
||||
/* Get a four-byte little-endian integer and return 0 on success and the value
|
||||
in *ret. Otherwise -1 is returned and *ret is not modified. */
|
||||
local int gz_next4(state, ret)
|
||||
gz_statep state;
|
||||
unsigned long *ret;
|
||||
{
|
||||
int ch;
|
||||
unsigned long val;
|
||||
z_streamp strm = &(state->strm);
|
||||
|
||||
val = NEXT();
|
||||
val += (unsigned)NEXT() << 8;
|
||||
val += (unsigned long)NEXT() << 16;
|
||||
ch = NEXT();
|
||||
if (ch == -1)
|
||||
return -1;
|
||||
val += (unsigned long)ch << 24;
|
||||
*ret = val;
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* Look for gzip header, set up for inflate or copy. state->have must be zero.
|
||||
If this is the first time in, allocate required memory. state->how will be
|
||||
left unchanged if there is no more input data available, will be set to COPY
|
||||
if there is no gzip header and direct copying will be performed, or it will
|
||||
be set to GZIP for decompression, and the gzip header will be skipped so
|
||||
that the next available input data is the raw deflate stream. If direct
|
||||
copying, then leftover input data from the input buffer will be copied to
|
||||
the output buffer. In that case, all further file reads will be directly to
|
||||
either the output buffer or a user buffer. If decompressing, the inflate
|
||||
state and the check value will be initialized. gz_head() will return 0 on
|
||||
success or -1 on failure. Failures may include read errors or gzip header
|
||||
errors. */
|
||||
local int gz_head(state)
|
||||
gz_statep state;
|
||||
{
|
||||
z_streamp strm = &(state->strm);
|
||||
int flags;
|
||||
unsigned len;
|
||||
|
||||
/* allocate read buffers and inflate memory */
|
||||
if (state->size == 0) {
|
||||
/* allocate buffers */
|
||||
state->in = malloc(state->want);
|
||||
state->out = malloc(state->want << 1);
|
||||
if (state->in == NULL || state->out == NULL) {
|
||||
if (state->out != NULL)
|
||||
free(state->out);
|
||||
if (state->in != NULL)
|
||||
free(state->in);
|
||||
gz_error(state, Z_MEM_ERROR, "out of memory");
|
||||
return -1;
|
||||
}
|
||||
state->size = state->want;
|
||||
|
||||
/* allocate inflate memory */
|
||||
state->strm.zalloc = Z_NULL;
|
||||
state->strm.zfree = Z_NULL;
|
||||
state->strm.opaque = Z_NULL;
|
||||
state->strm.avail_in = 0;
|
||||
state->strm.next_in = Z_NULL;
|
||||
if (inflateInit2(&(state->strm), -15) != Z_OK) { /* raw inflate */
|
||||
free(state->out);
|
||||
free(state->in);
|
||||
state->size = 0;
|
||||
gz_error(state, Z_MEM_ERROR, "out of memory");
|
||||
return -1;
|
||||
}
|
||||
}
|
||||
|
||||
/* get some data in the input buffer */
|
||||
if (strm->avail_in == 0) {
|
||||
if (gz_avail(state) == -1)
|
||||
return -1;
|
||||
if (strm->avail_in == 0)
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* look for the gzip magic header bytes 31 and 139 */
|
||||
if (strm->next_in[0] == 31) {
|
||||
strm->avail_in--;
|
||||
strm->next_in++;
|
||||
if (strm->avail_in == 0 && gz_avail(state) == -1)
|
||||
return -1;
|
||||
if (strm->avail_in && strm->next_in[0] == 139) {
|
||||
/* we have a gzip header, woo hoo! */
|
||||
strm->avail_in--;
|
||||
strm->next_in++;
|
||||
|
||||
/* skip rest of header */
|
||||
if (NEXT() != 8) { /* compression method */
|
||||
gz_error(state, Z_DATA_ERROR, "unknown compression method");
|
||||
return -1;
|
||||
}
|
||||
flags = NEXT();
|
||||
if (flags & 0xe0) { /* reserved flag bits */
|
||||
gz_error(state, Z_DATA_ERROR, "unknown header flags set");
|
||||
return -1;
|
||||
}
|
||||
NEXT(); /* modification time */
|
||||
NEXT();
|
||||
NEXT();
|
||||
NEXT();
|
||||
NEXT(); /* extra flags */
|
||||
NEXT(); /* operating system */
|
||||
if (flags & 4) { /* extra field */
|
||||
len = (unsigned)NEXT();
|
||||
len += (unsigned)NEXT() << 8;
|
||||
while (len--)
|
||||
if (NEXT() < 0)
|
||||
break;
|
||||
}
|
||||
if (flags & 8) /* file name */
|
||||
while (NEXT() > 0)
|
||||
;
|
||||
if (flags & 16) /* comment */
|
||||
while (NEXT() > 0)
|
||||
;
|
||||
if (flags & 2) { /* header crc */
|
||||
NEXT();
|
||||
NEXT();
|
||||
}
|
||||
/* an unexpected end of file is not checked for here -- it will be
|
||||
noticed on the first request for uncompressed data */
|
||||
|
||||
/* set up for decompression */
|
||||
inflateReset(strm);
|
||||
strm->adler = crc32(0L, Z_NULL, 0);
|
||||
state->how = GZIP;
|
||||
state->direct = 0;
|
||||
return 0;
|
||||
}
|
||||
else {
|
||||
/* not a gzip file -- save first byte (31) and fall to raw i/o */
|
||||
state->out[0] = 31;
|
||||
state->have = 1;
|
||||
}
|
||||
}
|
||||
|
||||
/* doing raw i/o, save start of raw data for seeking, copy any leftover
|
||||
input to output -- this assumes that the output buffer is larger than
|
||||
the input buffer, which also assures space for gzungetc() */
|
||||
state->raw = state->pos;
|
||||
state->next = state->out;
|
||||
if (strm->avail_in) {
|
||||
memcpy(state->next + state->have, strm->next_in, strm->avail_in);
|
||||
state->have += strm->avail_in;
|
||||
strm->avail_in = 0;
|
||||
}
|
||||
state->how = COPY;
|
||||
state->direct = 1;
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* Decompress from input to the provided next_out and avail_out in the state.
|
||||
If the end of the compressed data is reached, then verify the gzip trailer
|
||||
check value and length (modulo 2^32). state->have and state->next are set
|
||||
to point to the just decompressed data, and the crc is updated. If the
|
||||
trailer is verified, state->how is reset to LOOK to look for the next gzip
|
||||
stream or raw data, once state->have is depleted. Returns 0 on success, -1
|
||||
on failure. Failures may include invalid compressed data or a failed gzip
|
||||
trailer verification. */
|
||||
local int gz_decomp(state)
|
||||
gz_statep state;
|
||||
{
|
||||
int ret;
|
||||
unsigned had;
|
||||
unsigned long crc, len;
|
||||
z_streamp strm = &(state->strm);
|
||||
|
||||
/* fill output buffer up to end of deflate stream */
|
||||
had = strm->avail_out;
|
||||
do {
|
||||
/* get more input for inflate() */
|
||||
if (strm->avail_in == 0 && gz_avail(state) == -1)
|
||||
return -1;
|
||||
if (strm->avail_in == 0) {
|
||||
gz_error(state, Z_DATA_ERROR, "unexpected end of file");
|
||||
return -1;
|
||||
}
|
||||
|
||||
/* decompress and handle errors */
|
||||
ret = inflate(strm, Z_NO_FLUSH);
|
||||
if (ret == Z_STREAM_ERROR || ret == Z_NEED_DICT) {
|
||||
gz_error(state, Z_STREAM_ERROR,
|
||||
"internal error: inflate stream corrupt");
|
||||
return -1;
|
||||
}
|
||||
if (ret == Z_MEM_ERROR) {
|
||||
gz_error(state, Z_MEM_ERROR, "out of memory");
|
||||
return -1;
|
||||
}
|
||||
if (ret == Z_DATA_ERROR) { /* deflate stream invalid */
|
||||
gz_error(state, Z_DATA_ERROR,
|
||||
strm->msg == NULL ? "compressed data error" : strm->msg);
|
||||
return -1;
|
||||
}
|
||||
} while (strm->avail_out && ret != Z_STREAM_END);
|
||||
|
||||
/* update available output and crc check value */
|
||||
state->have = had - strm->avail_out;
|
||||
state->next = strm->next_out - state->have;
|
||||
strm->adler = crc32(strm->adler, state->next, state->have);
|
||||
|
||||
/* check gzip trailer if at end of deflate stream */
|
||||
if (ret == Z_STREAM_END) {
|
||||
if (gz_next4(state, &crc) == -1 || gz_next4(state, &len) == -1) {
|
||||
gz_error(state, Z_DATA_ERROR, "unexpected end of file");
|
||||
return -1;
|
||||
}
|
||||
if (crc != strm->adler) {
|
||||
gz_error(state, Z_DATA_ERROR, "incorrect data check");
|
||||
return -1;
|
||||
}
|
||||
if (len != (strm->total_out & 0xffffffffL)) {
|
||||
gz_error(state, Z_DATA_ERROR, "incorrect length check");
|
||||
return -1;
|
||||
}
|
||||
state->how = LOOK; /* ready for next stream, once have is 0 (leave
|
||||
state->direct unchanged to remember how) */
|
||||
}
|
||||
|
||||
/* good decompression */
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* Make data and put in the output buffer. Assumes that state->have == 0.
|
||||
Data is either copied from the input file or decompressed from the input
|
||||
file depending on state->how. If state->how is LOOK, then a gzip header is
|
||||
looked for (and skipped if found) to determine wither to copy or decompress.
|
||||
Returns -1 on error, otherwise 0. gz_make() will leave state->have as COPY
|
||||
or GZIP unless the end of the input file has been reached and all data has
|
||||
been processed. */
|
||||
local int gz_make(state)
|
||||
gz_statep state;
|
||||
{
|
||||
z_streamp strm = &(state->strm);
|
||||
|
||||
if (state->how == LOOK) { /* look for gzip header */
|
||||
if (gz_head(state) == -1)
|
||||
return -1;
|
||||
if (state->have) /* got some data from gz_head() */
|
||||
return 0;
|
||||
}
|
||||
if (state->how == COPY) { /* straight copy */
|
||||
if (gz_load(state, state->out, state->size << 1, &(state->have)) == -1)
|
||||
return -1;
|
||||
state->next = state->out;
|
||||
}
|
||||
else if (state->how == GZIP) { /* decompress */
|
||||
strm->avail_out = state->size << 1;
|
||||
strm->next_out = state->out;
|
||||
if (gz_decomp(state) == -1)
|
||||
return -1;
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* Skip len uncompressed bytes of output. Return -1 on error, 0 on success. */
|
||||
local int gz_skip(state, len)
|
||||
gz_statep state;
|
||||
z_off64_t len;
|
||||
{
|
||||
unsigned n;
|
||||
|
||||
/* skip over len bytes or reach end-of-file, whichever comes first */
|
||||
while (len)
|
||||
/* skip over whatever is in output buffer */
|
||||
if (state->have) {
|
||||
n = GT_OFF(state->have) || (z_off64_t)state->have > len ?
|
||||
(unsigned)len : state->have;
|
||||
state->have -= n;
|
||||
state->next += n;
|
||||
state->pos += n;
|
||||
len -= n;
|
||||
}
|
||||
|
||||
/* output buffer empty -- return if we're at the end of the input */
|
||||
else if (state->eof && state->strm.avail_in == 0)
|
||||
break;
|
||||
|
||||
/* need more data to skip -- load up output buffer */
|
||||
else {
|
||||
/* get more output, looking for header if required */
|
||||
if (gz_make(state) == -1)
|
||||
return -1;
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* -- see zlib.h -- */
|
||||
int ZEXPORT gzread(file, buf, len)
|
||||
gzFile file;
|
||||
voidp buf;
|
||||
unsigned len;
|
||||
{
|
||||
unsigned got, n;
|
||||
gz_statep state;
|
||||
z_streamp strm;
|
||||
|
||||
/* get internal structure */
|
||||
if (file == NULL)
|
||||
return -1;
|
||||
state = (gz_statep)file;
|
||||
strm = &(state->strm);
|
||||
|
||||
/* check that we're reading and that there's no error */
|
||||
if (state->mode != GZ_READ || state->err != Z_OK)
|
||||
return -1;
|
||||
|
||||
/* since an int is returned, make sure len fits in one, otherwise return
|
||||
with an error (this avoids the flaw in the interface) */
|
||||
if ((int)len < 0) {
|
||||
gz_error(state, Z_BUF_ERROR, "requested length does not fit in int");
|
||||
return -1;
|
||||
}
|
||||
|
||||
/* if len is zero, avoid unnecessary operations */
|
||||
if (len == 0)
|
||||
return 0;
|
||||
|
||||
/* process a skip request */
|
||||
if (state->seek) {
|
||||
state->seek = 0;
|
||||
if (gz_skip(state, state->skip) == -1)
|
||||
return -1;
|
||||
}
|
||||
|
||||
/* get len bytes to buf, or less than len if at the end */
|
||||
got = 0;
|
||||
do {
|
||||
/* first just try copying data from the output buffer */
|
||||
if (state->have) {
|
||||
n = state->have > len ? len : state->have;
|
||||
memcpy(buf, state->next, n);
|
||||
state->next += n;
|
||||
state->have -= n;
|
||||
}
|
||||
|
||||
/* output buffer empty -- return if we're at the end of the input */
|
||||
else if (state->eof && strm->avail_in == 0)
|
||||
break;
|
||||
|
||||
/* need output data -- for small len or new stream load up our output
|
||||
buffer */
|
||||
else if (state->how == LOOK || len < (state->size << 1)) {
|
||||
/* get more output, looking for header if required */
|
||||
if (gz_make(state) == -1)
|
||||
return -1;
|
||||
continue; /* no progress yet -- go back to memcpy() above */
|
||||
/* the copy above assures that we will leave with space in the
|
||||
output buffer, allowing at least one gzungetc() to succeed */
|
||||
}
|
||||
|
||||
/* large len -- read directly into user buffer */
|
||||
else if (state->how == COPY) { /* read directly */
|
||||
if (gz_load(state, buf, len, &n) == -1)
|
||||
return -1;
|
||||
}
|
||||
|
||||
/* large len -- decompress directly into user buffer */
|
||||
else { /* state->how == GZIP */
|
||||
strm->avail_out = len;
|
||||
strm->next_out = buf;
|
||||
if (gz_decomp(state) == -1)
|
||||
return -1;
|
||||
n = state->have;
|
||||
state->have = 0;
|
||||
}
|
||||
|
||||
/* update progress */
|
||||
len -= n;
|
||||
buf = (char *)buf + n;
|
||||
got += n;
|
||||
state->pos += n;
|
||||
} while (len);
|
||||
|
||||
/* return number of bytes read into user buffer (will fit in int) */
|
||||
return (int)got;
|
||||
}
|
||||
|
||||
/* -- see zlib.h -- */
|
||||
int ZEXPORT gzgetc(file)
|
||||
gzFile file;
|
||||
{
|
||||
int ret;
|
||||
unsigned char buf[1];
|
||||
gz_statep state;
|
||||
|
||||
/* get internal structure */
|
||||
if (file == NULL)
|
||||
return -1;
|
||||
state = (gz_statep)file;
|
||||
|
||||
/* check that we're reading and that there's no error */
|
||||
if (state->mode != GZ_READ || state->err != Z_OK)
|
||||
return -1;
|
||||
|
||||
/* try output buffer (no need to check for skip request) */
|
||||
if (state->have) {
|
||||
state->have--;
|
||||
state->pos++;
|
||||
return *(state->next)++;
|
||||
}
|
||||
|
||||
/* nothing there -- try gzread() */
|
||||
ret = gzread(file, buf, 1);
|
||||
return ret < 1 ? -1 : buf[0];
|
||||
}
|
||||
|
||||
/* -- see zlib.h -- */
|
||||
int ZEXPORT gzungetc(c, file)
|
||||
int c;
|
||||
gzFile file;
|
||||
{
|
||||
gz_statep state;
|
||||
|
||||
/* get internal structure */
|
||||
if (file == NULL)
|
||||
return -1;
|
||||
state = (gz_statep)file;
|
||||
|
||||
/* check that we're reading and that there's no error */
|
||||
if (state->mode != GZ_READ || state->err != Z_OK)
|
||||
return -1;
|
||||
|
||||
/* process a skip request */
|
||||
if (state->seek) {
|
||||
state->seek = 0;
|
||||
if (gz_skip(state, state->skip) == -1)
|
||||
return -1;
|
||||
}
|
||||
|
||||
/* can't push EOF */
|
||||
if (c < 0)
|
||||
return -1;
|
||||
|
||||
/* if output buffer empty, put byte at end (allows more pushing) */
|
||||
if (state->have == 0) {
|
||||
state->have = 1;
|
||||
state->next = state->out + (state->size << 1) - 1;
|
||||
state->next[0] = c;
|
||||
state->pos--;
|
||||
return c;
|
||||
}
|
||||
|
||||
/* if no room, give up (must have already done a gzungetc()) */
|
||||
if (state->have == (state->size << 1)) {
|
||||
gz_error(state, Z_BUF_ERROR, "out of room to push characters");
|
||||
return -1;
|
||||
}
|
||||
|
||||
/* slide output data if needed and insert byte before existing data */
|
||||
if (state->next == state->out) {
|
||||
unsigned char *src = state->out + state->have;
|
||||
unsigned char *dest = state->out + (state->size << 1);
|
||||
while (src > state->out)
|
||||
*--dest = *--src;
|
||||
state->next = dest;
|
||||
}
|
||||
state->have++;
|
||||
state->next--;
|
||||
state->next[0] = c;
|
||||
state->pos--;
|
||||
return c;
|
||||
}
|
||||
|
||||
/* -- see zlib.h -- */
|
||||
char * ZEXPORT gzgets(file, buf, len)
|
||||
gzFile file;
|
||||
char *buf;
|
||||
int len;
|
||||
{
|
||||
unsigned left, n;
|
||||
char *str;
|
||||
unsigned char *eol;
|
||||
gz_statep state;
|
||||
|
||||
/* check parameters and get internal structure */
|
||||
if (file == NULL || buf == NULL || len < 1)
|
||||
return NULL;
|
||||
state = (gz_statep)file;
|
||||
|
||||
/* check that we're reading and that there's no error */
|
||||
if (state->mode != GZ_READ || state->err != Z_OK)
|
||||
return NULL;
|
||||
|
||||
/* process a skip request */
|
||||
if (state->seek) {
|
||||
state->seek = 0;
|
||||
if (gz_skip(state, state->skip) == -1)
|
||||
return NULL;
|
||||
}
|
||||
|
||||
/* copy output bytes up to new line or len - 1, whichever comes first --
|
||||
append a terminating zero to the string (we don't check for a zero in
|
||||
the contents, let the user worry about that) */
|
||||
str = buf;
|
||||
left = (unsigned)len - 1;
|
||||
if (left) do {
|
||||
/* assure that something is in the output buffer */
|
||||
if (state->have == 0) {
|
||||
if (gz_make(state) == -1)
|
||||
return NULL; /* error */
|
||||
if (state->have == 0) { /* end of file */
|
||||
if (buf == str) /* got bupkus */
|
||||
return NULL;
|
||||
break; /* got something -- return it */
|
||||
}
|
||||
}
|
||||
|
||||
/* look for end-of-line in current output buffer */
|
||||
n = state->have > left ? left : state->have;
|
||||
eol = memchr(state->next, '\n', n);
|
||||
if (eol != NULL)
|
||||
n = (unsigned)(eol - state->next) + 1;
|
||||
|
||||
/* copy through end-of-line, or remainder if not found */
|
||||
memcpy(buf, state->next, n);
|
||||
state->have -= n;
|
||||
state->next += n;
|
||||
state->pos += n;
|
||||
left -= n;
|
||||
buf += n;
|
||||
} while (left && eol == NULL);
|
||||
|
||||
/* found end-of-line or out of space -- terminate string and return it */
|
||||
buf[0] = 0;
|
||||
return str;
|
||||
}
|
||||
|
||||
/* -- see zlib.h -- */
|
||||
int ZEXPORT gzdirect(file)
|
||||
gzFile file;
|
||||
{
|
||||
gz_statep state;
|
||||
|
||||
/* get internal structure */
|
||||
if (file == NULL)
|
||||
return 0;
|
||||
state = (gz_statep)file;
|
||||
|
||||
/* check that we're reading */
|
||||
if (state->mode != GZ_READ)
|
||||
return 0;
|
||||
|
||||
/* if the state is not known, but we can find out, then do so (this is
|
||||
mainly for right after a gzopen() or gzdopen()) */
|
||||
if (state->how == LOOK && state->have == 0)
|
||||
(void)gz_head(state);
|
||||
|
||||
/* return 1 if reading direct, 0 if decompressing a gzip stream */
|
||||
return state->direct;
|
||||
}
|
||||
|
||||
/* -- see zlib.h -- */
|
||||
int ZEXPORT gzclose_r(file)
|
||||
gzFile file;
|
||||
{
|
||||
int ret;
|
||||
gz_statep state;
|
||||
|
||||
/* get internal structure */
|
||||
if (file == NULL)
|
||||
return Z_STREAM_ERROR;
|
||||
state = (gz_statep)file;
|
||||
|
||||
/* check that we're reading */
|
||||
if (state->mode != GZ_READ)
|
||||
return Z_STREAM_ERROR;
|
||||
|
||||
/* free memory and close file */
|
||||
if (state->size) {
|
||||
inflateEnd(&(state->strm));
|
||||
free(state->out);
|
||||
free(state->in);
|
||||
}
|
||||
gz_error(state, Z_OK, NULL);
|
||||
free(state->path);
|
||||
ret = close(state->fd);
|
||||
free(state);
|
||||
return ret ? Z_ERRNO : Z_OK;
|
||||
}
|
532
lib/libz/gzwrite.c
Normal file
532
lib/libz/gzwrite.c
Normal file
@ -0,0 +1,532 @@
|
||||
/* gzwrite.c -- zlib functions for writing gzip files
|
||||
* Copyright (C) 2004, 2005, 2010 Mark Adler
|
||||
* For conditions of distribution and use, see copyright notice in zlib.h
|
||||
*/
|
||||
|
||||
#include "gzguts.h"
|
||||
#include <unistd.h>
|
||||
|
||||
/* Local functions */
|
||||
local int gz_init OF((gz_statep));
|
||||
local int gz_comp OF((gz_statep, int));
|
||||
local int gz_zero OF((gz_statep, z_off64_t));
|
||||
|
||||
/* Initialize state for writing a gzip file. Mark initialization by setting
|
||||
state->size to non-zero. Return -1 on failure or 0 on success. */
|
||||
local int gz_init(state)
|
||||
gz_statep state;
|
||||
{
|
||||
int ret;
|
||||
z_streamp strm = &(state->strm);
|
||||
|
||||
/* allocate input and output buffers */
|
||||
state->in = malloc(state->want);
|
||||
state->out = malloc(state->want);
|
||||
if (state->in == NULL || state->out == NULL) {
|
||||
if (state->out != NULL)
|
||||
free(state->out);
|
||||
if (state->in != NULL)
|
||||
free(state->in);
|
||||
gz_error(state, Z_MEM_ERROR, "out of memory");
|
||||
return -1;
|
||||
}
|
||||
|
||||
/* allocate deflate memory, set up for gzip compression */
|
||||
strm->zalloc = Z_NULL;
|
||||
strm->zfree = Z_NULL;
|
||||
strm->opaque = Z_NULL;
|
||||
ret = deflateInit2(strm, state->level, Z_DEFLATED,
|
||||
15 + 16, 8, state->strategy);
|
||||
if (ret != Z_OK) {
|
||||
free(state->in);
|
||||
gz_error(state, Z_MEM_ERROR, "out of memory");
|
||||
return -1;
|
||||
}
|
||||
|
||||
/* mark state as initialized */
|
||||
state->size = state->want;
|
||||
|
||||
/* initialize write buffer */
|
||||
strm->avail_out = state->size;
|
||||
strm->next_out = state->out;
|
||||
state->next = strm->next_out;
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* Compress whatever is at avail_in and next_in and write to the output file.
|
||||
Return -1 if there is an error writing to the output file, otherwise 0.
|
||||
flush is assumed to be a valid deflate() flush value. If flush is Z_FINISH,
|
||||
then the deflate() state is reset to start a new gzip stream. */
|
||||
local int gz_comp(state, flush)
|
||||
gz_statep state;
|
||||
int flush;
|
||||
{
|
||||
int ret, got;
|
||||
unsigned have;
|
||||
z_streamp strm = &(state->strm);
|
||||
|
||||
/* allocate memory if this is the first time through */
|
||||
if (state->size == 0 && gz_init(state) == -1)
|
||||
return -1;
|
||||
|
||||
/* run deflate() on provided input until it produces no more output */
|
||||
ret = Z_OK;
|
||||
do {
|
||||
/* write out current buffer contents if full, or if flushing, but if
|
||||
doing Z_FINISH then don't write until we get to Z_STREAM_END */
|
||||
if (strm->avail_out == 0 || (flush != Z_NO_FLUSH &&
|
||||
(flush != Z_FINISH || ret == Z_STREAM_END))) {
|
||||
have = (unsigned)(strm->next_out - state->next);
|
||||
if (have && ((got = write(state->fd, state->next, have)) < 0 ||
|
||||
(unsigned)got != have)) {
|
||||
gz_error(state, Z_ERRNO, zstrerror());
|
||||
return -1;
|
||||
}
|
||||
if (strm->avail_out == 0) {
|
||||
strm->avail_out = state->size;
|
||||
strm->next_out = state->out;
|
||||
}
|
||||
state->next = strm->next_out;
|
||||
}
|
||||
|
||||
/* compress */
|
||||
have = strm->avail_out;
|
||||
ret = deflate(strm, flush);
|
||||
if (ret == Z_STREAM_ERROR) {
|
||||
gz_error(state, Z_STREAM_ERROR,
|
||||
"internal error: deflate stream corrupt");
|
||||
return -1;
|
||||
}
|
||||
have -= strm->avail_out;
|
||||
} while (have);
|
||||
|
||||
/* if that completed a deflate stream, allow another to start */
|
||||
if (flush == Z_FINISH)
|
||||
deflateReset(strm);
|
||||
|
||||
/* all done, no errors */
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* Compress len zeros to output. Return -1 on error, 0 on success. */
|
||||
local int gz_zero(state, len)
|
||||
gz_statep state;
|
||||
z_off64_t len;
|
||||
{
|
||||
int first;
|
||||
unsigned n;
|
||||
z_streamp strm = &(state->strm);
|
||||
|
||||
/* consume whatever's left in the input buffer */
|
||||
if (strm->avail_in && gz_comp(state, Z_NO_FLUSH) == -1)
|
||||
return -1;
|
||||
|
||||
/* compress len zeros (len guaranteed > 0) */
|
||||
first = 1;
|
||||
while (len) {
|
||||
n = GT_OFF(state->size) || (z_off64_t)state->size > len ?
|
||||
(unsigned)len : state->size;
|
||||
if (first) {
|
||||
memset(state->in, 0, n);
|
||||
first = 0;
|
||||
}
|
||||
strm->avail_in = n;
|
||||
strm->next_in = state->in;
|
||||
state->pos += n;
|
||||
if (gz_comp(state, Z_NO_FLUSH) == -1)
|
||||
return -1;
|
||||
len -= n;
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* -- see zlib.h -- */
|
||||
int ZEXPORT gzwrite(file, buf, len)
|
||||
gzFile file;
|
||||
voidpc buf;
|
||||
unsigned len;
|
||||
{
|
||||
unsigned put = len;
|
||||
unsigned n;
|
||||
gz_statep state;
|
||||
z_streamp strm;
|
||||
|
||||
/* get internal structure */
|
||||
if (file == NULL)
|
||||
return 0;
|
||||
state = (gz_statep)file;
|
||||
strm = &(state->strm);
|
||||
|
||||
/* check that we're writing and that there's no error */
|
||||
if (state->mode != GZ_WRITE || state->err != Z_OK)
|
||||
return 0;
|
||||
|
||||
/* since an int is returned, make sure len fits in one, otherwise return
|
||||
with an error (this avoids the flaw in the interface) */
|
||||
if ((int)len < 0) {
|
||||
gz_error(state, Z_BUF_ERROR, "requested length does not fit in int");
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* if len is zero, avoid unnecessary operations */
|
||||
if (len == 0)
|
||||
return 0;
|
||||
|
||||
/* allocate memory if this is the first time through */
|
||||
if (state->size == 0 && gz_init(state) == -1)
|
||||
return 0;
|
||||
|
||||
/* check for seek request */
|
||||
if (state->seek) {
|
||||
state->seek = 0;
|
||||
if (gz_zero(state, state->skip) == -1)
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* for small len, copy to input buffer, otherwise compress directly */
|
||||
if (len < state->size) {
|
||||
/* copy to input buffer, compress when full */
|
||||
do {
|
||||
if (strm->avail_in == 0)
|
||||
strm->next_in = state->in;
|
||||
n = state->size - strm->avail_in;
|
||||
if (n > len)
|
||||
n = len;
|
||||
memcpy(strm->next_in + strm->avail_in, buf, n);
|
||||
strm->avail_in += n;
|
||||
state->pos += n;
|
||||
buf = (char *)buf + n;
|
||||
len -= n;
|
||||
if (len && gz_comp(state, Z_NO_FLUSH) == -1)
|
||||
return 0;
|
||||
} while (len);
|
||||
}
|
||||
else {
|
||||
/* consume whatever's left in the input buffer */
|
||||
if (strm->avail_in && gz_comp(state, Z_NO_FLUSH) == -1)
|
||||
return 0;
|
||||
|
||||
/* directly compress user buffer to file */
|
||||
strm->avail_in = len;
|
||||
strm->next_in = (voidp)buf;
|
||||
state->pos += len;
|
||||
if (gz_comp(state, Z_NO_FLUSH) == -1)
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* input was all buffered or compressed (put will fit in int) */
|
||||
return (int)put;
|
||||
}
|
||||
|
||||
/* -- see zlib.h -- */
|
||||
int ZEXPORT gzputc(file, c)
|
||||
gzFile file;
|
||||
int c;
|
||||
{
|
||||
unsigned char buf[1];
|
||||
gz_statep state;
|
||||
z_streamp strm;
|
||||
|
||||
/* get internal structure */
|
||||
if (file == NULL)
|
||||
return -1;
|
||||
state = (gz_statep)file;
|
||||
strm = &(state->strm);
|
||||
|
||||
/* check that we're writing and that there's no error */
|
||||
if (state->mode != GZ_WRITE || state->err != Z_OK)
|
||||
return -1;
|
||||
|
||||
/* check for seek request */
|
||||
if (state->seek) {
|
||||
state->seek = 0;
|
||||
if (gz_zero(state, state->skip) == -1)
|
||||
return -1;
|
||||
}
|
||||
|
||||
/* try writing to input buffer for speed (state->size == 0 if buffer not
|
||||
initialized) */
|
||||
if (strm->avail_in < state->size) {
|
||||
if (strm->avail_in == 0)
|
||||
strm->next_in = state->in;
|
||||
strm->next_in[strm->avail_in++] = c;
|
||||
state->pos++;
|
||||
return c;
|
||||
}
|
||||
|
||||
/* no room in buffer or not initialized, use gz_write() */
|
||||
buf[0] = c;
|
||||
if (gzwrite(file, buf, 1) != 1)
|
||||
return -1;
|
||||
return c;
|
||||
}
|
||||
|
||||
/* -- see zlib.h -- */
|
||||
int ZEXPORT gzputs(file, str)
|
||||
gzFile file;
|
||||
const char *str;
|
||||
{
|
||||
int ret;
|
||||
unsigned len;
|
||||
|
||||
/* write string */
|
||||
len = (unsigned)strlen(str);
|
||||
ret = gzwrite(file, str, len);
|
||||
return ret == 0 && len != 0 ? -1 : ret;
|
||||
}
|
||||
|
||||
#ifdef STDC
|
||||
#include <stdarg.h>
|
||||
|
||||
/* -- see zlib.h -- */
|
||||
int ZEXPORTVA gzprintf (gzFile file, const char *format, ...)
|
||||
{
|
||||
int size, len;
|
||||
gz_statep state;
|
||||
z_streamp strm;
|
||||
va_list va;
|
||||
|
||||
/* get internal structure */
|
||||
if (file == NULL)
|
||||
return -1;
|
||||
state = (gz_statep)file;
|
||||
strm = &(state->strm);
|
||||
|
||||
/* check that we're writing and that there's no error */
|
||||
if (state->mode != GZ_WRITE || state->err != Z_OK)
|
||||
return 0;
|
||||
|
||||
/* make sure we have some buffer space */
|
||||
if (state->size == 0 && gz_init(state) == -1)
|
||||
return 0;
|
||||
|
||||
/* check for seek request */
|
||||
if (state->seek) {
|
||||
state->seek = 0;
|
||||
if (gz_zero(state, state->skip) == -1)
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* consume whatever's left in the input buffer */
|
||||
if (strm->avail_in && gz_comp(state, Z_NO_FLUSH) == -1)
|
||||
return 0;
|
||||
|
||||
/* do the printf() into the input buffer, put length in len */
|
||||
size = (int)(state->size);
|
||||
state->in[size - 1] = 0;
|
||||
va_start(va, format);
|
||||
#ifdef NO_vsnprintf
|
||||
# ifdef HAS_vsprintf_void
|
||||
(void)vsprintf(state->in, format, va);
|
||||
va_end(va);
|
||||
for (len = 0; len < size; len++)
|
||||
if (state->in[len] == 0) break;
|
||||
# else
|
||||
len = vsprintf(state->in, format, va);
|
||||
va_end(va);
|
||||
# endif
|
||||
#else
|
||||
# ifdef HAS_vsnprintf_void
|
||||
(void)vsnprintf(state->in, size, format, va);
|
||||
va_end(va);
|
||||
len = strlen(state->in);
|
||||
# else
|
||||
len = vsnprintf((char *)(state->in), size, format, va);
|
||||
va_end(va);
|
||||
# endif
|
||||
#endif
|
||||
|
||||
/* check that printf() results fit in buffer */
|
||||
if (len <= 0 || len >= (int)size || state->in[size - 1] != 0)
|
||||
return 0;
|
||||
|
||||
/* update buffer and position, defer compression until needed */
|
||||
strm->avail_in = (unsigned)len;
|
||||
strm->next_in = state->in;
|
||||
state->pos += len;
|
||||
return len;
|
||||
}
|
||||
|
||||
#else /* !STDC */
|
||||
|
||||
/* -- see zlib.h -- */
|
||||
int ZEXPORTVA gzprintf (file, format, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10,
|
||||
a11, a12, a13, a14, a15, a16, a17, a18, a19, a20)
|
||||
gzFile file;
|
||||
const char *format;
|
||||
int a1, a2, a3, a4, a5, a6, a7, a8, a9, a10,
|
||||
a11, a12, a13, a14, a15, a16, a17, a18, a19, a20;
|
||||
{
|
||||
int size, len;
|
||||
gz_statep state;
|
||||
z_streamp strm;
|
||||
|
||||
/* get internal structure */
|
||||
if (file == NULL)
|
||||
return -1;
|
||||
state = (gz_statep)file;
|
||||
strm = &(state->strm);
|
||||
|
||||
/* check that we're writing and that there's no error */
|
||||
if (state->mode != GZ_WRITE || state->err != Z_OK)
|
||||
return 0;
|
||||
|
||||
/* make sure we have some buffer space */
|
||||
if (state->size == 0 && gz_init(state) == -1)
|
||||
return 0;
|
||||
|
||||
/* check for seek request */
|
||||
if (state->seek) {
|
||||
state->seek = 0;
|
||||
if (gz_zero(state, state->skip) == -1)
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* consume whatever's left in the input buffer */
|
||||
if (strm->avail_in && gz_comp(state, Z_NO_FLUSH) == -1)
|
||||
return 0;
|
||||
|
||||
/* do the printf() into the input buffer, put length in len */
|
||||
size = (int)(state->size);
|
||||
state->in[size - 1] = 0;
|
||||
#ifdef NO_snprintf
|
||||
# ifdef HAS_sprintf_void
|
||||
sprintf(state->in, format, a1, a2, a3, a4, a5, a6, a7, a8,
|
||||
a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20);
|
||||
for (len = 0; len < size; len++)
|
||||
if (state->in[len] == 0) break;
|
||||
# else
|
||||
len = sprintf(state->in, format, a1, a2, a3, a4, a5, a6, a7, a8,
|
||||
a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20);
|
||||
# endif
|
||||
#else
|
||||
# ifdef HAS_snprintf_void
|
||||
snprintf(state->in, size, format, a1, a2, a3, a4, a5, a6, a7, a8,
|
||||
a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20);
|
||||
len = strlen(state->in);
|
||||
# else
|
||||
len = snprintf(state->in, size, format, a1, a2, a3, a4, a5, a6, a7, a8,
|
||||
a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20);
|
||||
# endif
|
||||
#endif
|
||||
|
||||
/* check that printf() results fit in buffer */
|
||||
if (len <= 0 || len >= (int)size || state->in[size - 1] != 0)
|
||||
return 0;
|
||||
|
||||
/* update buffer and position, defer compression until needed */
|
||||
strm->avail_in = (unsigned)len;
|
||||
strm->next_in = state->in;
|
||||
state->pos += len;
|
||||
return len;
|
||||
}
|
||||
|
||||
#endif
|
||||
|
||||
/* -- see zlib.h -- */
|
||||
int ZEXPORT gzflush(file, flush)
|
||||
gzFile file;
|
||||
int flush;
|
||||
{
|
||||
gz_statep state;
|
||||
|
||||
/* get internal structure */
|
||||
if (file == NULL)
|
||||
return -1;
|
||||
state = (gz_statep)file;
|
||||
|
||||
/* check that we're writing and that there's no error */
|
||||
if (state->mode != GZ_WRITE || state->err != Z_OK)
|
||||
return Z_STREAM_ERROR;
|
||||
|
||||
/* check flush parameter */
|
||||
if (flush < 0 || flush > Z_FINISH)
|
||||
return Z_STREAM_ERROR;
|
||||
|
||||
/* check for seek request */
|
||||
if (state->seek) {
|
||||
state->seek = 0;
|
||||
if (gz_zero(state, state->skip) == -1)
|
||||
return -1;
|
||||
}
|
||||
|
||||
/* compress remaining data with requested flush */
|
||||
gz_comp(state, flush);
|
||||
return state->err;
|
||||
}
|
||||
|
||||
/* -- see zlib.h -- */
|
||||
int ZEXPORT gzsetparams(file, level, strategy)
|
||||
gzFile file;
|
||||
int level;
|
||||
int strategy;
|
||||
{
|
||||
gz_statep state;
|
||||
z_streamp strm;
|
||||
|
||||
/* get internal structure */
|
||||
if (file == NULL)
|
||||
return Z_STREAM_ERROR;
|
||||
state = (gz_statep)file;
|
||||
strm = &(state->strm);
|
||||
|
||||
/* check that we're writing and that there's no error */
|
||||
if (state->mode != GZ_WRITE || state->err != Z_OK)
|
||||
return Z_STREAM_ERROR;
|
||||
|
||||
/* if no change is requested, then do nothing */
|
||||
if (level == state->level && strategy == state->strategy)
|
||||
return Z_OK;
|
||||
|
||||
/* check for seek request */
|
||||
if (state->seek) {
|
||||
state->seek = 0;
|
||||
if (gz_zero(state, state->skip) == -1)
|
||||
return -1;
|
||||
}
|
||||
|
||||
/* change compression parameters for subsequent input */
|
||||
if (state->size) {
|
||||
/* flush previous input with previous parameters before changing */
|
||||
if (strm->avail_in && gz_comp(state, Z_PARTIAL_FLUSH) == -1)
|
||||
return state->err;
|
||||
deflateParams(strm, level, strategy);
|
||||
}
|
||||
state->level = level;
|
||||
state->strategy = strategy;
|
||||
return Z_OK;
|
||||
}
|
||||
|
||||
/* -- see zlib.h -- */
|
||||
int ZEXPORT gzclose_w(file)
|
||||
gzFile file;
|
||||
{
|
||||
int ret = 0;
|
||||
gz_statep state;
|
||||
|
||||
/* get internal structure */
|
||||
if (file == NULL)
|
||||
return Z_STREAM_ERROR;
|
||||
state = (gz_statep)file;
|
||||
|
||||
/* check that we're writing */
|
||||
if (state->mode != GZ_WRITE)
|
||||
return Z_STREAM_ERROR;
|
||||
|
||||
/* check for seek request */
|
||||
if (state->seek) {
|
||||
state->seek = 0;
|
||||
ret += gz_zero(state, state->skip);
|
||||
}
|
||||
|
||||
/* flush, free memory, and close file */
|
||||
ret += gz_comp(state, Z_FINISH);
|
||||
(void)deflateEnd(&(state->strm));
|
||||
free(state->out);
|
||||
free(state->in);
|
||||
gz_error(state, Z_OK, NULL);
|
||||
free(state->path);
|
||||
ret += close(state->fd);
|
||||
free(state);
|
||||
return ret ? Z_ERRNO : Z_OK;
|
||||
}
|
@ -1,5 +1,5 @@
|
||||
/* infback.c -- inflate using a call-back interface
|
||||
* Copyright (C) 1995-2005 Mark Adler
|
||||
* Copyright (C) 1995-2009 Mark Adler
|
||||
* For conditions of distribution and use, see copyright notice in zlib.h
|
||||
*/
|
||||
|
||||
@ -55,7 +55,7 @@ int stream_size;
|
||||
state->wbits = windowBits;
|
||||
state->wsize = 1U << windowBits;
|
||||
state->window = window;
|
||||
state->write = 0;
|
||||
state->wnext = 0;
|
||||
state->whave = 0;
|
||||
return Z_OK;
|
||||
}
|
||||
@ -253,7 +253,7 @@ void FAR *out_desc;
|
||||
unsigned bits; /* bits in bit buffer */
|
||||
unsigned copy; /* number of stored or match bytes to copy */
|
||||
unsigned char FAR *from; /* where to copy match bytes from */
|
||||
code this; /* current decoding table entry */
|
||||
code here; /* current decoding table entry */
|
||||
code last; /* parent table entry */
|
||||
unsigned len; /* length to copy for repeats, bits to drop */
|
||||
int ret; /* return code */
|
||||
@ -389,19 +389,19 @@ void FAR *out_desc;
|
||||
state->have = 0;
|
||||
while (state->have < state->nlen + state->ndist) {
|
||||
for (;;) {
|
||||
this = state->lencode[BITS(state->lenbits)];
|
||||
if ((unsigned)(this.bits) <= bits) break;
|
||||
here = state->lencode[BITS(state->lenbits)];
|
||||
if ((unsigned)(here.bits) <= bits) break;
|
||||
PULLBYTE();
|
||||
}
|
||||
if (this.val < 16) {
|
||||
NEEDBITS(this.bits);
|
||||
DROPBITS(this.bits);
|
||||
state->lens[state->have++] = this.val;
|
||||
if (here.val < 16) {
|
||||
NEEDBITS(here.bits);
|
||||
DROPBITS(here.bits);
|
||||
state->lens[state->have++] = here.val;
|
||||
}
|
||||
else {
|
||||
if (this.val == 16) {
|
||||
NEEDBITS(this.bits + 2);
|
||||
DROPBITS(this.bits);
|
||||
if (here.val == 16) {
|
||||
NEEDBITS(here.bits + 2);
|
||||
DROPBITS(here.bits);
|
||||
if (state->have == 0) {
|
||||
strm->msg = (char *)"invalid bit length repeat";
|
||||
state->mode = BAD;
|
||||
@ -411,16 +411,16 @@ void FAR *out_desc;
|
||||
copy = 3 + BITS(2);
|
||||
DROPBITS(2);
|
||||
}
|
||||
else if (this.val == 17) {
|
||||
NEEDBITS(this.bits + 3);
|
||||
DROPBITS(this.bits);
|
||||
else if (here.val == 17) {
|
||||
NEEDBITS(here.bits + 3);
|
||||
DROPBITS(here.bits);
|
||||
len = 0;
|
||||
copy = 3 + BITS(3);
|
||||
DROPBITS(3);
|
||||
}
|
||||
else {
|
||||
NEEDBITS(this.bits + 7);
|
||||
DROPBITS(this.bits);
|
||||
NEEDBITS(here.bits + 7);
|
||||
DROPBITS(here.bits);
|
||||
len = 0;
|
||||
copy = 11 + BITS(7);
|
||||
DROPBITS(7);
|
||||
@ -438,7 +438,16 @@ void FAR *out_desc;
|
||||
/* handle error breaks in while */
|
||||
if (state->mode == BAD) break;
|
||||
|
||||
/* build code tables */
|
||||
/* check for end-of-block code (better have one) */
|
||||
if (state->lens[256] == 0) {
|
||||
strm->msg = (char *)"invalid code -- missing end-of-block";
|
||||
state->mode = BAD;
|
||||
break;
|
||||
}
|
||||
|
||||
/* build code tables -- note: do not change the lenbits or distbits
|
||||
values here (9 and 6) without reading the comments in inftrees.h
|
||||
concerning the ENOUGH constants, which depend on those values */
|
||||
state->next = state->codes;
|
||||
state->lencode = (code const FAR *)(state->next);
|
||||
state->lenbits = 9;
|
||||
@ -474,28 +483,28 @@ void FAR *out_desc;
|
||||
|
||||
/* get a literal, length, or end-of-block code */
|
||||
for (;;) {
|
||||
this = state->lencode[BITS(state->lenbits)];
|
||||
if ((unsigned)(this.bits) <= bits) break;
|
||||
here = state->lencode[BITS(state->lenbits)];
|
||||
if ((unsigned)(here.bits) <= bits) break;
|
||||
PULLBYTE();
|
||||
}
|
||||
if (this.op && (this.op & 0xf0) == 0) {
|
||||
last = this;
|
||||
if (here.op && (here.op & 0xf0) == 0) {
|
||||
last = here;
|
||||
for (;;) {
|
||||
this = state->lencode[last.val +
|
||||
here = state->lencode[last.val +
|
||||
(BITS(last.bits + last.op) >> last.bits)];
|
||||
if ((unsigned)(last.bits + this.bits) <= bits) break;
|
||||
if ((unsigned)(last.bits + here.bits) <= bits) break;
|
||||
PULLBYTE();
|
||||
}
|
||||
DROPBITS(last.bits);
|
||||
}
|
||||
DROPBITS(this.bits);
|
||||
state->length = (unsigned)this.val;
|
||||
DROPBITS(here.bits);
|
||||
state->length = (unsigned)here.val;
|
||||
|
||||
/* process literal */
|
||||
if (this.op == 0) {
|
||||
Tracevv((stderr, this.val >= 0x20 && this.val < 0x7f ?
|
||||
if (here.op == 0) {
|
||||
Tracevv((stderr, here.val >= 0x20 && here.val < 0x7f ?
|
||||
"inflate: literal '%c'\n" :
|
||||
"inflate: literal 0x%02x\n", this.val));
|
||||
"inflate: literal 0x%02x\n", here.val));
|
||||
ROOM();
|
||||
*put++ = (unsigned char)(state->length);
|
||||
left--;
|
||||
@ -504,21 +513,21 @@ void FAR *out_desc;
|
||||
}
|
||||
|
||||
/* process end of block */
|
||||
if (this.op & 32) {
|
||||
if (here.op & 32) {
|
||||
Tracevv((stderr, "inflate: end of block\n"));
|
||||
state->mode = TYPE;
|
||||
break;
|
||||
}
|
||||
|
||||
/* invalid code */
|
||||
if (this.op & 64) {
|
||||
if (here.op & 64) {
|
||||
strm->msg = (char *)"invalid literal/length code";
|
||||
state->mode = BAD;
|
||||
break;
|
||||
}
|
||||
|
||||
/* length code -- get extra bits, if any */
|
||||
state->extra = (unsigned)(this.op) & 15;
|
||||
state->extra = (unsigned)(here.op) & 15;
|
||||
if (state->extra != 0) {
|
||||
NEEDBITS(state->extra);
|
||||
state->length += BITS(state->extra);
|
||||
@ -528,30 +537,30 @@ void FAR *out_desc;
|
||||
|
||||
/* get distance code */
|
||||
for (;;) {
|
||||
this = state->distcode[BITS(state->distbits)];
|
||||
if ((unsigned)(this.bits) <= bits) break;
|
||||
here = state->distcode[BITS(state->distbits)];
|
||||
if ((unsigned)(here.bits) <= bits) break;
|
||||
PULLBYTE();
|
||||
}
|
||||
if ((this.op & 0xf0) == 0) {
|
||||
last = this;
|
||||
if ((here.op & 0xf0) == 0) {
|
||||
last = here;
|
||||
for (;;) {
|
||||
this = state->distcode[last.val +
|
||||
here = state->distcode[last.val +
|
||||
(BITS(last.bits + last.op) >> last.bits)];
|
||||
if ((unsigned)(last.bits + this.bits) <= bits) break;
|
||||
if ((unsigned)(last.bits + here.bits) <= bits) break;
|
||||
PULLBYTE();
|
||||
}
|
||||
DROPBITS(last.bits);
|
||||
}
|
||||
DROPBITS(this.bits);
|
||||
if (this.op & 64) {
|
||||
DROPBITS(here.bits);
|
||||
if (here.op & 64) {
|
||||
strm->msg = (char *)"invalid distance code";
|
||||
state->mode = BAD;
|
||||
break;
|
||||
}
|
||||
state->offset = (unsigned)this.val;
|
||||
state->offset = (unsigned)here.val;
|
||||
|
||||
/* get distance extra bits, if any */
|
||||
state->extra = (unsigned)(this.op) & 15;
|
||||
state->extra = (unsigned)(here.op) & 15;
|
||||
if (state->extra != 0) {
|
||||
NEEDBITS(state->extra);
|
||||
state->offset += BITS(state->extra);
|
||||
|
@ -1,5 +1,5 @@
|
||||
/* inffast.c -- fast decoding
|
||||
* Copyright (C) 1995-2004 Mark Adler
|
||||
* Copyright (C) 1995-2008 Mark Adler
|
||||
* For conditions of distribution and use, see copyright notice in zlib.h
|
||||
*/
|
||||
|
||||
@ -79,7 +79,7 @@ unsigned start; /* inflate()'s starting value for strm->avail_out */
|
||||
#endif
|
||||
unsigned wsize; /* window size or zero if not using window */
|
||||
unsigned whave; /* valid bytes in the window */
|
||||
unsigned write; /* window write index */
|
||||
unsigned wnext; /* window write index */
|
||||
unsigned char FAR *window; /* allocated sliding window, if wsize != 0 */
|
||||
unsigned long hold; /* local strm->hold */
|
||||
unsigned bits; /* local strm->bits */
|
||||
@ -87,7 +87,7 @@ unsigned start; /* inflate()'s starting value for strm->avail_out */
|
||||
code const FAR *dcode; /* local strm->distcode */
|
||||
unsigned lmask; /* mask for first level of length codes */
|
||||
unsigned dmask; /* mask for first level of distance codes */
|
||||
code this; /* retrieved table entry */
|
||||
code here; /* retrieved table entry */
|
||||
unsigned op; /* code bits, operation, extra bits, or */
|
||||
/* window position, window bytes to copy */
|
||||
unsigned len; /* match length, unused bytes */
|
||||
@ -106,7 +106,7 @@ unsigned start; /* inflate()'s starting value for strm->avail_out */
|
||||
#endif
|
||||
wsize = state->wsize;
|
||||
whave = state->whave;
|
||||
write = state->write;
|
||||
wnext = state->wnext;
|
||||
window = state->window;
|
||||
hold = state->hold;
|
||||
bits = state->bits;
|
||||
@ -124,20 +124,20 @@ unsigned start; /* inflate()'s starting value for strm->avail_out */
|
||||
hold += (unsigned long)(PUP(in)) << bits;
|
||||
bits += 8;
|
||||
}
|
||||
this = lcode[hold & lmask];
|
||||
here = lcode[hold & lmask];
|
||||
dolen:
|
||||
op = (unsigned)(this.bits);
|
||||
op = (unsigned)(here.bits);
|
||||
hold >>= op;
|
||||
bits -= op;
|
||||
op = (unsigned)(this.op);
|
||||
op = (unsigned)(here.op);
|
||||
if (op == 0) { /* literal */
|
||||
Tracevv((stderr, this.val >= 0x20 && this.val < 0x7f ?
|
||||
Tracevv((stderr, here.val >= 0x20 && here.val < 0x7f ?
|
||||
"inflate: literal '%c'\n" :
|
||||
"inflate: literal 0x%02x\n", this.val));
|
||||
PUP(out) = (unsigned char)(this.val);
|
||||
"inflate: literal 0x%02x\n", here.val));
|
||||
PUP(out) = (unsigned char)(here.val);
|
||||
}
|
||||
else if (op & 16) { /* length base */
|
||||
len = (unsigned)(this.val);
|
||||
len = (unsigned)(here.val);
|
||||
op &= 15; /* number of extra bits */
|
||||
if (op) {
|
||||
if (bits < op) {
|
||||
@ -155,14 +155,14 @@ unsigned start; /* inflate()'s starting value for strm->avail_out */
|
||||
hold += (unsigned long)(PUP(in)) << bits;
|
||||
bits += 8;
|
||||
}
|
||||
this = dcode[hold & dmask];
|
||||
here = dcode[hold & dmask];
|
||||
dodist:
|
||||
op = (unsigned)(this.bits);
|
||||
op = (unsigned)(here.bits);
|
||||
hold >>= op;
|
||||
bits -= op;
|
||||
op = (unsigned)(this.op);
|
||||
op = (unsigned)(here.op);
|
||||
if (op & 16) { /* distance base */
|
||||
dist = (unsigned)(this.val);
|
||||
dist = (unsigned)(here.val);
|
||||
op &= 15; /* number of extra bits */
|
||||
if (bits < op) {
|
||||
hold += (unsigned long)(PUP(in)) << bits;
|
||||
@ -187,12 +187,34 @@ unsigned start; /* inflate()'s starting value for strm->avail_out */
|
||||
if (dist > op) { /* see if copy from window */
|
||||
op = dist - op; /* distance back in window */
|
||||
if (op > whave) {
|
||||
strm->msg = (char *)"invalid distance too far back";
|
||||
state->mode = BAD;
|
||||
break;
|
||||
if (state->sane) {
|
||||
strm->msg =
|
||||
(char *)"invalid distance too far back";
|
||||
state->mode = BAD;
|
||||
break;
|
||||
}
|
||||
#ifdef INFLATE_ALLOW_INVALID_DISTANCE_TOOFAR_ARRR
|
||||
if (len <= op - whave) {
|
||||
do {
|
||||
PUP(out) = 0;
|
||||
} while (--len);
|
||||
continue;
|
||||
}
|
||||
len -= op - whave;
|
||||
do {
|
||||
PUP(out) = 0;
|
||||
} while (--op > whave);
|
||||
if (op == 0) {
|
||||
from = out - dist;
|
||||
do {
|
||||
PUP(out) = PUP(from);
|
||||
} while (--len);
|
||||
continue;
|
||||
}
|
||||
#endif
|
||||
}
|
||||
from = window - OFF;
|
||||
if (write == 0) { /* very common case */
|
||||
if (wnext == 0) { /* very common case */
|
||||
from += wsize - op;
|
||||
if (op < len) { /* some from window */
|
||||
len -= op;
|
||||
@ -202,17 +224,17 @@ unsigned start; /* inflate()'s starting value for strm->avail_out */
|
||||
from = out - dist; /* rest from output */
|
||||
}
|
||||
}
|
||||
else if (write < op) { /* wrap around window */
|
||||
from += wsize + write - op;
|
||||
op -= write;
|
||||
else if (wnext < op) { /* wrap around window */
|
||||
from += wsize + wnext - op;
|
||||
op -= wnext;
|
||||
if (op < len) { /* some from end of window */
|
||||
len -= op;
|
||||
do {
|
||||
PUP(out) = PUP(from);
|
||||
} while (--op);
|
||||
from = window - OFF;
|
||||
if (write < len) { /* some from start of window */
|
||||
op = write;
|
||||
if (wnext < len) { /* some from start of window */
|
||||
op = wnext;
|
||||
len -= op;
|
||||
do {
|
||||
PUP(out) = PUP(from);
|
||||
@ -222,7 +244,7 @@ unsigned start; /* inflate()'s starting value for strm->avail_out */
|
||||
}
|
||||
}
|
||||
else { /* contiguous in window */
|
||||
from += write - op;
|
||||
from += wnext - op;
|
||||
if (op < len) { /* some from window */
|
||||
len -= op;
|
||||
do {
|
||||
@ -259,7 +281,7 @@ unsigned start; /* inflate()'s starting value for strm->avail_out */
|
||||
}
|
||||
}
|
||||
else if ((op & 64) == 0) { /* 2nd level distance code */
|
||||
this = dcode[this.val + (hold & ((1U << op) - 1))];
|
||||
here = dcode[here.val + (hold & ((1U << op) - 1))];
|
||||
goto dodist;
|
||||
}
|
||||
else {
|
||||
@ -269,7 +291,7 @@ unsigned start; /* inflate()'s starting value for strm->avail_out */
|
||||
}
|
||||
}
|
||||
else if ((op & 64) == 0) { /* 2nd level length code */
|
||||
this = lcode[this.val + (hold & ((1U << op) - 1))];
|
||||
here = lcode[here.val + (hold & ((1U << op) - 1))];
|
||||
goto dolen;
|
||||
}
|
||||
else if (op & 32) { /* end-of-block */
|
||||
@ -305,7 +327,7 @@ unsigned start; /* inflate()'s starting value for strm->avail_out */
|
||||
inflate_fast() speedups that turned out slower (on a PowerPC G3 750CXe):
|
||||
- Using bit fields for code structure
|
||||
- Different op definition to avoid & for extra bits (do & for table bits)
|
||||
- Three separate decoding do-loops for direct, window, and write == 0
|
||||
- Three separate decoding do-loops for direct, window, and wnext == 0
|
||||
- Special case for distance > 1 copies to do overlapped load and store copy
|
||||
- Explicit branch predictions (based on measured branch probabilities)
|
||||
- Deferring match copy and interspersed it with decoding subsequent codes
|
||||
|
@ -1,5 +1,5 @@
|
||||
/* inflate.c -- zlib decompression
|
||||
* Copyright (C) 1995-2005 Mark Adler
|
||||
* Copyright (C) 1995-2010 Mark Adler
|
||||
* For conditions of distribution and use, see copyright notice in zlib.h
|
||||
*/
|
||||
|
||||
@ -45,7 +45,7 @@
|
||||
* - Rearrange window copies in inflate_fast() for speed and simplification
|
||||
* - Unroll last copy for window match in inflate_fast()
|
||||
* - Use local copies of window variables in inflate_fast() for speed
|
||||
* - Pull out common write == 0 case for speed in inflate_fast()
|
||||
* - Pull out common wnext == 0 case for speed in inflate_fast()
|
||||
* - Make op and len in inflate_fast() unsigned for consistency
|
||||
* - Add FAR to lcode and dcode declarations in inflate_fast()
|
||||
* - Simplified bad distance check in inflate_fast()
|
||||
@ -117,28 +117,52 @@ z_streamp strm;
|
||||
state->head = Z_NULL;
|
||||
state->wsize = 0;
|
||||
state->whave = 0;
|
||||
state->write = 0;
|
||||
state->wnext = 0;
|
||||
state->hold = 0;
|
||||
state->bits = 0;
|
||||
state->lencode = state->distcode = state->next = state->codes;
|
||||
state->sane = 1;
|
||||
state->back = -1;
|
||||
Tracev((stderr, "inflate: reset\n"));
|
||||
return Z_OK;
|
||||
}
|
||||
|
||||
int ZEXPORT inflatePrime(strm, bits, value)
|
||||
int ZEXPORT inflateReset2(strm, windowBits)
|
||||
z_streamp strm;
|
||||
int bits;
|
||||
int value;
|
||||
int windowBits;
|
||||
{
|
||||
int wrap;
|
||||
struct inflate_state FAR *state;
|
||||
|
||||
/* get the state */
|
||||
if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
|
||||
state = (struct inflate_state FAR *)strm->state;
|
||||
if (bits > 16 || state->bits + bits > 32) return Z_STREAM_ERROR;
|
||||
value &= (1L << bits) - 1;
|
||||
state->hold += value << state->bits;
|
||||
state->bits += bits;
|
||||
return Z_OK;
|
||||
|
||||
/* extract wrap request from windowBits parameter */
|
||||
if (windowBits < 0) {
|
||||
wrap = 0;
|
||||
windowBits = -windowBits;
|
||||
}
|
||||
else {
|
||||
wrap = (windowBits >> 4) + 1;
|
||||
#ifdef GUNZIP
|
||||
if (windowBits < 48)
|
||||
windowBits &= 15;
|
||||
#endif
|
||||
}
|
||||
|
||||
/* set number of window bits, free window if different */
|
||||
if (windowBits && (windowBits < 8 || windowBits > 15))
|
||||
return Z_STREAM_ERROR;
|
||||
if (state->window != Z_NULL && state->wbits != (unsigned)windowBits) {
|
||||
ZFREE(strm, state->window);
|
||||
state->window = Z_NULL;
|
||||
}
|
||||
|
||||
/* update state and reset the rest of it */
|
||||
state->wrap = wrap;
|
||||
state->wbits = (unsigned)windowBits;
|
||||
return inflateReset(strm);
|
||||
}
|
||||
|
||||
int ZEXPORT inflateInit2_(strm, windowBits, version, stream_size)
|
||||
@ -147,6 +171,7 @@ int windowBits;
|
||||
const char *version;
|
||||
int stream_size;
|
||||
{
|
||||
int ret;
|
||||
struct inflate_state FAR *state;
|
||||
|
||||
if (version == Z_NULL || version[0] != ZLIB_VERSION[0] ||
|
||||
@ -164,24 +189,13 @@ int stream_size;
|
||||
if (state == Z_NULL) return Z_MEM_ERROR;
|
||||
Tracev((stderr, "inflate: allocated\n"));
|
||||
strm->state = (struct internal_state FAR *)state;
|
||||
if (windowBits < 0) {
|
||||
state->wrap = 0;
|
||||
windowBits = -windowBits;
|
||||
}
|
||||
else {
|
||||
state->wrap = (windowBits >> 4) + 1;
|
||||
#ifdef GUNZIP
|
||||
if (windowBits < 48) windowBits &= 15;
|
||||
#endif
|
||||
}
|
||||
if (windowBits < 8 || windowBits > 15) {
|
||||
state->window = Z_NULL;
|
||||
ret = inflateReset2(strm, windowBits);
|
||||
if (ret != Z_OK) {
|
||||
ZFREE(strm, state);
|
||||
strm->state = Z_NULL;
|
||||
return Z_STREAM_ERROR;
|
||||
}
|
||||
state->wbits = (unsigned)windowBits;
|
||||
state->window = Z_NULL;
|
||||
return inflateReset(strm);
|
||||
return ret;
|
||||
}
|
||||
|
||||
int ZEXPORT inflateInit_(strm, version, stream_size)
|
||||
@ -192,6 +206,27 @@ int stream_size;
|
||||
return inflateInit2_(strm, DEF_WBITS, version, stream_size);
|
||||
}
|
||||
|
||||
int ZEXPORT inflatePrime(strm, bits, value)
|
||||
z_streamp strm;
|
||||
int bits;
|
||||
int value;
|
||||
{
|
||||
struct inflate_state FAR *state;
|
||||
|
||||
if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
|
||||
state = (struct inflate_state FAR *)strm->state;
|
||||
if (bits < 0) {
|
||||
state->hold = 0;
|
||||
state->bits = 0;
|
||||
return Z_OK;
|
||||
}
|
||||
if (bits > 16 || state->bits + bits > 32) return Z_STREAM_ERROR;
|
||||
value &= (1L << bits) - 1;
|
||||
state->hold += value << state->bits;
|
||||
state->bits += bits;
|
||||
return Z_OK;
|
||||
}
|
||||
|
||||
/*
|
||||
Return state with length and distance decoding tables and index sizes set to
|
||||
fixed code decoding. Normally this returns fixed tables from inffixed.h.
|
||||
@ -340,7 +375,7 @@ unsigned out;
|
||||
/* if window not in use yet, initialize */
|
||||
if (state->wsize == 0) {
|
||||
state->wsize = 1U << state->wbits;
|
||||
state->write = 0;
|
||||
state->wnext = 0;
|
||||
state->whave = 0;
|
||||
}
|
||||
|
||||
@ -348,22 +383,22 @@ unsigned out;
|
||||
copy = out - strm->avail_out;
|
||||
if (copy >= state->wsize) {
|
||||
zmemcpy(state->window, strm->next_out - state->wsize, state->wsize);
|
||||
state->write = 0;
|
||||
state->wnext = 0;
|
||||
state->whave = state->wsize;
|
||||
}
|
||||
else {
|
||||
dist = state->wsize - state->write;
|
||||
dist = state->wsize - state->wnext;
|
||||
if (dist > copy) dist = copy;
|
||||
zmemcpy(state->window + state->write, strm->next_out - copy, dist);
|
||||
zmemcpy(state->window + state->wnext, strm->next_out - copy, dist);
|
||||
copy -= dist;
|
||||
if (copy) {
|
||||
zmemcpy(state->window, strm->next_out - copy, copy);
|
||||
state->write = copy;
|
||||
state->wnext = copy;
|
||||
state->whave = state->wsize;
|
||||
}
|
||||
else {
|
||||
state->write += dist;
|
||||
if (state->write == state->wsize) state->write = 0;
|
||||
state->wnext += dist;
|
||||
if (state->wnext == state->wsize) state->wnext = 0;
|
||||
if (state->whave < state->wsize) state->whave += dist;
|
||||
}
|
||||
}
|
||||
@ -564,7 +599,7 @@ int flush;
|
||||
unsigned in, out; /* save starting available input and output */
|
||||
unsigned copy; /* number of stored or match bytes to copy */
|
||||
unsigned char FAR *from; /* where to copy match bytes from */
|
||||
code this; /* current decoding table entry */
|
||||
code here; /* current decoding table entry */
|
||||
code last; /* parent table entry */
|
||||
unsigned len; /* length to copy for repeats, bits to drop */
|
||||
int ret; /* return code */
|
||||
@ -619,7 +654,9 @@ int flush;
|
||||
}
|
||||
DROPBITS(4);
|
||||
len = BITS(4) + 8;
|
||||
if (len > state->wbits) {
|
||||
if (state->wbits == 0)
|
||||
state->wbits = len;
|
||||
else if (len > state->wbits) {
|
||||
strm->msg = (char *)"invalid window size";
|
||||
state->mode = BAD;
|
||||
break;
|
||||
@ -771,7 +808,7 @@ int flush;
|
||||
strm->adler = state->check = adler32(0L, Z_NULL, 0);
|
||||
state->mode = TYPE;
|
||||
case TYPE:
|
||||
if (flush == Z_BLOCK) goto inf_leave;
|
||||
if (flush == Z_BLOCK || flush == Z_TREES) goto inf_leave;
|
||||
case TYPEDO:
|
||||
if (state->last) {
|
||||
BYTEBITS();
|
||||
@ -791,7 +828,11 @@ int flush;
|
||||
fixedtables(state);
|
||||
Tracev((stderr, "inflate: fixed codes block%s\n",
|
||||
state->last ? " (last)" : ""));
|
||||
state->mode = LEN; /* decode codes */
|
||||
state->mode = LEN_; /* decode codes */
|
||||
if (flush == Z_TREES) {
|
||||
DROPBITS(2);
|
||||
goto inf_leave;
|
||||
}
|
||||
break;
|
||||
case 2: /* dynamic block */
|
||||
Tracev((stderr, "inflate: dynamic codes block%s\n",
|
||||
@ -816,6 +857,9 @@ int flush;
|
||||
Tracev((stderr, "inflate: stored length %u\n",
|
||||
state->length));
|
||||
INITBITS();
|
||||
state->mode = COPY_;
|
||||
if (flush == Z_TREES) goto inf_leave;
|
||||
case COPY_:
|
||||
state->mode = COPY;
|
||||
case COPY:
|
||||
copy = state->length;
|
||||
@ -876,19 +920,19 @@ int flush;
|
||||
case CODELENS:
|
||||
while (state->have < state->nlen + state->ndist) {
|
||||
for (;;) {
|
||||
this = state->lencode[BITS(state->lenbits)];
|
||||
if ((unsigned)(this.bits) <= bits) break;
|
||||
here = state->lencode[BITS(state->lenbits)];
|
||||
if ((unsigned)(here.bits) <= bits) break;
|
||||
PULLBYTE();
|
||||
}
|
||||
if (this.val < 16) {
|
||||
NEEDBITS(this.bits);
|
||||
DROPBITS(this.bits);
|
||||
state->lens[state->have++] = this.val;
|
||||
if (here.val < 16) {
|
||||
NEEDBITS(here.bits);
|
||||
DROPBITS(here.bits);
|
||||
state->lens[state->have++] = here.val;
|
||||
}
|
||||
else {
|
||||
if (this.val == 16) {
|
||||
NEEDBITS(this.bits + 2);
|
||||
DROPBITS(this.bits);
|
||||
if (here.val == 16) {
|
||||
NEEDBITS(here.bits + 2);
|
||||
DROPBITS(here.bits);
|
||||
if (state->have == 0) {
|
||||
strm->msg = (char *)"invalid bit length repeat";
|
||||
state->mode = BAD;
|
||||
@ -898,16 +942,16 @@ int flush;
|
||||
copy = 3 + BITS(2);
|
||||
DROPBITS(2);
|
||||
}
|
||||
else if (this.val == 17) {
|
||||
NEEDBITS(this.bits + 3);
|
||||
DROPBITS(this.bits);
|
||||
else if (here.val == 17) {
|
||||
NEEDBITS(here.bits + 3);
|
||||
DROPBITS(here.bits);
|
||||
len = 0;
|
||||
copy = 3 + BITS(3);
|
||||
DROPBITS(3);
|
||||
}
|
||||
else {
|
||||
NEEDBITS(this.bits + 7);
|
||||
DROPBITS(this.bits);
|
||||
NEEDBITS(here.bits + 7);
|
||||
DROPBITS(here.bits);
|
||||
len = 0;
|
||||
copy = 11 + BITS(7);
|
||||
DROPBITS(7);
|
||||
@ -925,7 +969,16 @@ int flush;
|
||||
/* handle error breaks in while */
|
||||
if (state->mode == BAD) break;
|
||||
|
||||
/* build code tables */
|
||||
/* check for end-of-block code (better have one) */
|
||||
if (state->lens[256] == 0) {
|
||||
strm->msg = (char *)"invalid code -- missing end-of-block";
|
||||
state->mode = BAD;
|
||||
break;
|
||||
}
|
||||
|
||||
/* build code tables -- note: do not change the lenbits or distbits
|
||||
values here (9 and 6) without reading the comments in inftrees.h
|
||||
concerning the ENOUGH constants, which depend on those values */
|
||||
state->next = state->codes;
|
||||
state->lencode = (code const FAR *)(state->next);
|
||||
state->lenbits = 9;
|
||||
@ -946,88 +999,102 @@ int flush;
|
||||
break;
|
||||
}
|
||||
Tracev((stderr, "inflate: codes ok\n"));
|
||||
state->mode = LEN_;
|
||||
if (flush == Z_TREES) goto inf_leave;
|
||||
case LEN_:
|
||||
state->mode = LEN;
|
||||
case LEN:
|
||||
if (have >= 6 && left >= 258) {
|
||||
RESTORE();
|
||||
inflate_fast(strm, out);
|
||||
LOAD();
|
||||
if (state->mode == TYPE)
|
||||
state->back = -1;
|
||||
break;
|
||||
}
|
||||
state->back = 0;
|
||||
for (;;) {
|
||||
this = state->lencode[BITS(state->lenbits)];
|
||||
if ((unsigned)(this.bits) <= bits) break;
|
||||
here = state->lencode[BITS(state->lenbits)];
|
||||
if ((unsigned)(here.bits) <= bits) break;
|
||||
PULLBYTE();
|
||||
}
|
||||
if (this.op && (this.op & 0xf0) == 0) {
|
||||
last = this;
|
||||
if (here.op && (here.op & 0xf0) == 0) {
|
||||
last = here;
|
||||
for (;;) {
|
||||
this = state->lencode[last.val +
|
||||
here = state->lencode[last.val +
|
||||
(BITS(last.bits + last.op) >> last.bits)];
|
||||
if ((unsigned)(last.bits + this.bits) <= bits) break;
|
||||
if ((unsigned)(last.bits + here.bits) <= bits) break;
|
||||
PULLBYTE();
|
||||
}
|
||||
DROPBITS(last.bits);
|
||||
state->back += last.bits;
|
||||
}
|
||||
DROPBITS(this.bits);
|
||||
state->length = (unsigned)this.val;
|
||||
if ((int)(this.op) == 0) {
|
||||
Tracevv((stderr, this.val >= 0x20 && this.val < 0x7f ?
|
||||
DROPBITS(here.bits);
|
||||
state->back += here.bits;
|
||||
state->length = (unsigned)here.val;
|
||||
if ((int)(here.op) == 0) {
|
||||
Tracevv((stderr, here.val >= 0x20 && here.val < 0x7f ?
|
||||
"inflate: literal '%c'\n" :
|
||||
"inflate: literal 0x%02x\n", this.val));
|
||||
"inflate: literal 0x%02x\n", here.val));
|
||||
state->mode = LIT;
|
||||
break;
|
||||
}
|
||||
if (this.op & 32) {
|
||||
if (here.op & 32) {
|
||||
Tracevv((stderr, "inflate: end of block\n"));
|
||||
state->back = -1;
|
||||
state->mode = TYPE;
|
||||
break;
|
||||
}
|
||||
if (this.op & 64) {
|
||||
if (here.op & 64) {
|
||||
strm->msg = (char *)"invalid literal/length code";
|
||||
state->mode = BAD;
|
||||
break;
|
||||
}
|
||||
state->extra = (unsigned)(this.op) & 15;
|
||||
state->extra = (unsigned)(here.op) & 15;
|
||||
state->mode = LENEXT;
|
||||
case LENEXT:
|
||||
if (state->extra) {
|
||||
NEEDBITS(state->extra);
|
||||
state->length += BITS(state->extra);
|
||||
DROPBITS(state->extra);
|
||||
state->back += state->extra;
|
||||
}
|
||||
Tracevv((stderr, "inflate: length %u\n", state->length));
|
||||
state->was = state->length;
|
||||
state->mode = DIST;
|
||||
case DIST:
|
||||
for (;;) {
|
||||
this = state->distcode[BITS(state->distbits)];
|
||||
if ((unsigned)(this.bits) <= bits) break;
|
||||
here = state->distcode[BITS(state->distbits)];
|
||||
if ((unsigned)(here.bits) <= bits) break;
|
||||
PULLBYTE();
|
||||
}
|
||||
if ((this.op & 0xf0) == 0) {
|
||||
last = this;
|
||||
if ((here.op & 0xf0) == 0) {
|
||||
last = here;
|
||||
for (;;) {
|
||||
this = state->distcode[last.val +
|
||||
here = state->distcode[last.val +
|
||||
(BITS(last.bits + last.op) >> last.bits)];
|
||||
if ((unsigned)(last.bits + this.bits) <= bits) break;
|
||||
if ((unsigned)(last.bits + here.bits) <= bits) break;
|
||||
PULLBYTE();
|
||||
}
|
||||
DROPBITS(last.bits);
|
||||
state->back += last.bits;
|
||||
}
|
||||
DROPBITS(this.bits);
|
||||
if (this.op & 64) {
|
||||
DROPBITS(here.bits);
|
||||
state->back += here.bits;
|
||||
if (here.op & 64) {
|
||||
strm->msg = (char *)"invalid distance code";
|
||||
state->mode = BAD;
|
||||
break;
|
||||
}
|
||||
state->offset = (unsigned)this.val;
|
||||
state->extra = (unsigned)(this.op) & 15;
|
||||
state->offset = (unsigned)here.val;
|
||||
state->extra = (unsigned)(here.op) & 15;
|
||||
state->mode = DISTEXT;
|
||||
case DISTEXT:
|
||||
if (state->extra) {
|
||||
NEEDBITS(state->extra);
|
||||
state->offset += BITS(state->extra);
|
||||
DROPBITS(state->extra);
|
||||
state->back += state->extra;
|
||||
}
|
||||
#ifdef INFLATE_STRICT
|
||||
if (state->offset > state->dmax) {
|
||||
@ -1036,11 +1103,6 @@ int flush;
|
||||
break;
|
||||
}
|
||||
#endif
|
||||
if (state->offset > state->whave + out - left) {
|
||||
strm->msg = (char *)"invalid distance too far back";
|
||||
state->mode = BAD;
|
||||
break;
|
||||
}
|
||||
Tracevv((stderr, "inflate: distance %u\n", state->offset));
|
||||
state->mode = MATCH;
|
||||
case MATCH:
|
||||
@ -1048,12 +1110,32 @@ int flush;
|
||||
copy = out - left;
|
||||
if (state->offset > copy) { /* copy from window */
|
||||
copy = state->offset - copy;
|
||||
if (copy > state->write) {
|
||||
copy -= state->write;
|
||||
if (copy > state->whave) {
|
||||
if (state->sane) {
|
||||
strm->msg = (char *)"invalid distance too far back";
|
||||
state->mode = BAD;
|
||||
break;
|
||||
}
|
||||
#ifdef INFLATE_ALLOW_INVALID_DISTANCE_TOOFAR_ARRR
|
||||
Trace((stderr, "inflate.c too far\n"));
|
||||
copy -= state->whave;
|
||||
if (copy > state->length) copy = state->length;
|
||||
if (copy > left) copy = left;
|
||||
left -= copy;
|
||||
state->length -= copy;
|
||||
do {
|
||||
*put++ = 0;
|
||||
} while (--copy);
|
||||
if (state->length == 0) state->mode = LEN;
|
||||
break;
|
||||
#endif
|
||||
}
|
||||
if (copy > state->wnext) {
|
||||
copy -= state->wnext;
|
||||
from = state->window + (state->wsize - copy);
|
||||
}
|
||||
else
|
||||
from = state->window + (state->write - copy);
|
||||
from = state->window + (state->wnext - copy);
|
||||
if (copy > state->length) copy = state->length;
|
||||
}
|
||||
else { /* copy from output */
|
||||
@ -1146,7 +1228,8 @@ int flush;
|
||||
strm->adler = state->check =
|
||||
UPDATE(state->check, strm->next_out - out, out);
|
||||
strm->data_type = state->bits + (state->last ? 64 : 0) +
|
||||
(state->mode == TYPE ? 128 : 0);
|
||||
(state->mode == TYPE ? 128 : 0) +
|
||||
(state->mode == LEN_ || state->mode == COPY_ ? 256 : 0);
|
||||
if (((in == 0 && out == 0) || flush == Z_FINISH) && ret == Z_OK)
|
||||
ret = Z_BUF_ERROR;
|
||||
return ret;
|
||||
@ -1366,3 +1449,32 @@ z_streamp source;
|
||||
dest->state = (struct internal_state FAR *)copy;
|
||||
return Z_OK;
|
||||
}
|
||||
|
||||
int ZEXPORT inflateUndermine(strm, subvert)
|
||||
z_streamp strm;
|
||||
int subvert;
|
||||
{
|
||||
struct inflate_state FAR *state;
|
||||
|
||||
if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
|
||||
state = (struct inflate_state FAR *)strm->state;
|
||||
state->sane = !subvert;
|
||||
#ifdef INFLATE_ALLOW_INVALID_DISTANCE_TOOFAR_ARRR
|
||||
return Z_OK;
|
||||
#else
|
||||
state->sane = 1;
|
||||
return Z_DATA_ERROR;
|
||||
#endif
|
||||
}
|
||||
|
||||
long ZEXPORT inflateMark(strm)
|
||||
z_streamp strm;
|
||||
{
|
||||
struct inflate_state FAR *state;
|
||||
|
||||
if (strm == Z_NULL || strm->state == Z_NULL) return -1L << 16;
|
||||
state = (struct inflate_state FAR *)strm->state;
|
||||
return ((long)(state->back) << 16) +
|
||||
(state->mode == COPY ? state->length :
|
||||
(state->mode == MATCH ? state->was - state->length : 0));
|
||||
}
|
||||
|
@ -1,5 +1,5 @@
|
||||
/* inflate.h -- internal inflate state definition
|
||||
* Copyright (C) 1995-2004 Mark Adler
|
||||
* Copyright (C) 1995-2009 Mark Adler
|
||||
* For conditions of distribution and use, see copyright notice in zlib.h
|
||||
*/
|
||||
|
||||
@ -32,11 +32,13 @@ typedef enum {
|
||||
TYPE, /* i: waiting for type bits, including last-flag bit */
|
||||
TYPEDO, /* i: same, but skip check to exit inflate on new block */
|
||||
STORED, /* i: waiting for stored size (length and complement) */
|
||||
COPY_, /* i/o: same as COPY below, but only first time in */
|
||||
COPY, /* i/o: waiting for input or output to copy stored block */
|
||||
TABLE, /* i: waiting for dynamic block table lengths */
|
||||
LENLENS, /* i: waiting for code length code lengths */
|
||||
CODELENS, /* i: waiting for length/lit and distance code lengths */
|
||||
LEN, /* i: waiting for length/lit code */
|
||||
LEN_, /* i: same as LEN below, but only first time in */
|
||||
LEN, /* i: waiting for length/lit/eob code */
|
||||
LENEXT, /* i: waiting for length extra bits */
|
||||
DIST, /* i: waiting for distance code */
|
||||
DISTEXT, /* i: waiting for distance extra bits */
|
||||
@ -53,19 +55,21 @@ typedef enum {
|
||||
/*
|
||||
State transitions between above modes -
|
||||
|
||||
(most modes can go to the BAD or MEM mode -- not shown for clarity)
|
||||
(most modes can go to BAD or MEM on error -- not shown for clarity)
|
||||
|
||||
Process header:
|
||||
HEAD -> (gzip) or (zlib)
|
||||
(gzip) -> FLAGS -> TIME -> OS -> EXLEN -> EXTRA -> NAME
|
||||
NAME -> COMMENT -> HCRC -> TYPE
|
||||
HEAD -> (gzip) or (zlib) or (raw)
|
||||
(gzip) -> FLAGS -> TIME -> OS -> EXLEN -> EXTRA -> NAME -> COMMENT ->
|
||||
HCRC -> TYPE
|
||||
(zlib) -> DICTID or TYPE
|
||||
DICTID -> DICT -> TYPE
|
||||
(raw) -> TYPEDO
|
||||
Read deflate blocks:
|
||||
TYPE -> STORED or TABLE or LEN or CHECK
|
||||
STORED -> COPY -> TYPE
|
||||
TABLE -> LENLENS -> CODELENS -> LEN
|
||||
Read deflate codes:
|
||||
TYPE -> TYPEDO -> STORED or TABLE or LEN_ or CHECK
|
||||
STORED -> COPY_ -> COPY -> TYPE
|
||||
TABLE -> LENLENS -> CODELENS -> LEN_
|
||||
LEN_ -> LEN
|
||||
Read deflate codes in fixed or dynamic block:
|
||||
LEN -> LENEXT or LIT or TYPE
|
||||
LENEXT -> DIST -> DISTEXT -> MATCH -> LEN
|
||||
LIT -> LEN
|
||||
@ -73,7 +77,7 @@ typedef enum {
|
||||
CHECK -> LENGTH -> DONE
|
||||
*/
|
||||
|
||||
/* state maintained between inflate() calls. Approximately 7K bytes. */
|
||||
/* state maintained between inflate() calls. Approximately 10K bytes. */
|
||||
struct inflate_state {
|
||||
inflate_mode mode; /* current inflate mode */
|
||||
int last; /* true if processing last block */
|
||||
@ -88,7 +92,7 @@ struct inflate_state {
|
||||
unsigned wbits; /* log base 2 of requested window size */
|
||||
unsigned wsize; /* window size or zero if not using window */
|
||||
unsigned whave; /* valid bytes in the window */
|
||||
unsigned write; /* window write index */
|
||||
unsigned wnext; /* window write index */
|
||||
unsigned char FAR *window; /* allocated sliding window, if needed */
|
||||
/* bit accumulator */
|
||||
unsigned long hold; /* input bit accumulator */
|
||||
@ -112,4 +116,7 @@ struct inflate_state {
|
||||
unsigned short lens[320]; /* temporary storage for code lengths */
|
||||
unsigned short work[288]; /* work area for code table building */
|
||||
code codes[ENOUGH]; /* space for code tables */
|
||||
int sane; /* if false, allow invalid distance too far */
|
||||
int back; /* bits back of last unprocessed length/lit */
|
||||
unsigned was; /* initial length of match */
|
||||
};
|
||||
|
@ -1,5 +1,5 @@
|
||||
/* inftrees.c -- generate Huffman trees for efficient decoding
|
||||
* Copyright (C) 1995-2005 Mark Adler
|
||||
* Copyright (C) 1995-2010 Mark Adler
|
||||
* For conditions of distribution and use, see copyright notice in zlib.h
|
||||
*/
|
||||
|
||||
@ -9,7 +9,7 @@
|
||||
#define MAXBITS 15
|
||||
|
||||
const char inflate_copyright[] =
|
||||
" inflate 1.2.3 Copyright 1995-2005 Mark Adler ";
|
||||
" inflate 1.2.4 Copyright 1995-2010 Mark Adler ";
|
||||
/*
|
||||
If you use the zlib library in a product, an acknowledgment is welcome
|
||||
in the documentation of your product. If for some reason you cannot
|
||||
@ -50,7 +50,7 @@ unsigned short FAR *work;
|
||||
unsigned fill; /* index for replicating entries */
|
||||
unsigned low; /* low bits for current root entry */
|
||||
unsigned mask; /* mask for low root bits */
|
||||
code this; /* table entry for duplication */
|
||||
code here; /* table entry for duplication */
|
||||
code FAR *next; /* next available space in table */
|
||||
const unsigned short FAR *base; /* base value table to use */
|
||||
const unsigned short FAR *extra; /* extra bits table to use */
|
||||
@ -62,7 +62,7 @@ unsigned short FAR *work;
|
||||
35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0};
|
||||
static const unsigned short lext[31] = { /* Length codes 257..285 extra */
|
||||
16, 16, 16, 16, 16, 16, 16, 16, 17, 17, 17, 17, 18, 18, 18, 18,
|
||||
19, 19, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 16, 201, 196};
|
||||
19, 19, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21, 16, 64, 195};
|
||||
static const unsigned short dbase[32] = { /* Distance codes 0..29 base */
|
||||
1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
|
||||
257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
|
||||
@ -115,15 +115,15 @@ unsigned short FAR *work;
|
||||
if (count[max] != 0) break;
|
||||
if (root > max) root = max;
|
||||
if (max == 0) { /* no symbols to code at all */
|
||||
this.op = (unsigned char)64; /* invalid code marker */
|
||||
this.bits = (unsigned char)1;
|
||||
this.val = (unsigned short)0;
|
||||
*(*table)++ = this; /* make a table to force an error */
|
||||
*(*table)++ = this;
|
||||
here.op = (unsigned char)64; /* invalid code marker */
|
||||
here.bits = (unsigned char)1;
|
||||
here.val = (unsigned short)0;
|
||||
*(*table)++ = here; /* make a table to force an error */
|
||||
*(*table)++ = here;
|
||||
*bits = 1;
|
||||
return 0; /* no symbols, but wait for decoding to report error */
|
||||
}
|
||||
for (min = 1; min <= MAXBITS; min++)
|
||||
for (min = 1; min < max; min++)
|
||||
if (count[min] != 0) break;
|
||||
if (root < min) root = min;
|
||||
|
||||
@ -166,11 +166,10 @@ unsigned short FAR *work;
|
||||
entered in the tables.
|
||||
|
||||
used keeps track of how many table entries have been allocated from the
|
||||
provided *table space. It is checked when a LENS table is being made
|
||||
against the space in *table, ENOUGH, minus the maximum space needed by
|
||||
the worst case distance code, MAXD. This should never happen, but the
|
||||
sufficiency of ENOUGH has not been proven exhaustively, hence the check.
|
||||
This assumes that when type == LENS, bits == 9.
|
||||
provided *table space. It is checked for LENS and DIST tables against
|
||||
the constants ENOUGH_LENS and ENOUGH_DISTS to guard against changes in
|
||||
the initial root table size constants. See the comments in inftrees.h
|
||||
for more information.
|
||||
|
||||
sym increments through all symbols, and the loop terminates when
|
||||
all codes of length max, i.e. all codes, have been processed. This
|
||||
@ -209,24 +208,25 @@ unsigned short FAR *work;
|
||||
mask = used - 1; /* mask for comparing low */
|
||||
|
||||
/* check available table space */
|
||||
if (type == LENS && used >= ENOUGH - MAXD)
|
||||
if ((type == LENS && used >= ENOUGH_LENS) ||
|
||||
(type == DISTS && used >= ENOUGH_DISTS))
|
||||
return 1;
|
||||
|
||||
/* process all codes and make table entries */
|
||||
for (;;) {
|
||||
/* create table entry */
|
||||
this.bits = (unsigned char)(len - drop);
|
||||
here.bits = (unsigned char)(len - drop);
|
||||
if ((int)(work[sym]) < end) {
|
||||
this.op = (unsigned char)0;
|
||||
this.val = work[sym];
|
||||
here.op = (unsigned char)0;
|
||||
here.val = work[sym];
|
||||
}
|
||||
else if ((int)(work[sym]) > end) {
|
||||
this.op = (unsigned char)(extra[work[sym]]);
|
||||
this.val = base[work[sym]];
|
||||
here.op = (unsigned char)(extra[work[sym]]);
|
||||
here.val = base[work[sym]];
|
||||
}
|
||||
else {
|
||||
this.op = (unsigned char)(32 + 64); /* end of block */
|
||||
this.val = 0;
|
||||
here.op = (unsigned char)(32 + 64); /* end of block */
|
||||
here.val = 0;
|
||||
}
|
||||
|
||||
/* replicate for those indices with low len bits equal to huff */
|
||||
@ -235,7 +235,7 @@ unsigned short FAR *work;
|
||||
min = fill; /* save offset to next table */
|
||||
do {
|
||||
fill -= incr;
|
||||
next[(huff >> drop) + fill] = this;
|
||||
next[(huff >> drop) + fill] = here;
|
||||
} while (fill != 0);
|
||||
|
||||
/* backwards increment the len-bit code huff */
|
||||
@ -277,7 +277,8 @@ unsigned short FAR *work;
|
||||
|
||||
/* check for enough space */
|
||||
used += 1U << curr;
|
||||
if (type == LENS && used >= ENOUGH - MAXD)
|
||||
if ((type == LENS && used >= ENOUGH_LENS) ||
|
||||
(type == DISTS && used >= ENOUGH_DISTS))
|
||||
return 1;
|
||||
|
||||
/* point entry in root table to sub-table */
|
||||
@ -295,20 +296,20 @@ unsigned short FAR *work;
|
||||
through high index bits. When the current sub-table is filled, the loop
|
||||
drops back to the root table to fill in any remaining entries there.
|
||||
*/
|
||||
this.op = (unsigned char)64; /* invalid code marker */
|
||||
this.bits = (unsigned char)(len - drop);
|
||||
this.val = (unsigned short)0;
|
||||
here.op = (unsigned char)64; /* invalid code marker */
|
||||
here.bits = (unsigned char)(len - drop);
|
||||
here.val = (unsigned short)0;
|
||||
while (huff != 0) {
|
||||
/* when done with sub-table, drop back to root table */
|
||||
if (drop != 0 && (huff & mask) != low) {
|
||||
drop = 0;
|
||||
len = root;
|
||||
next = *table;
|
||||
this.bits = (unsigned char)len;
|
||||
here.bits = (unsigned char)len;
|
||||
}
|
||||
|
||||
/* put invalid code marker in table */
|
||||
next[huff >> drop] = this;
|
||||
next[huff >> drop] = here;
|
||||
|
||||
/* backwards increment the len-bit code huff */
|
||||
incr = 1U << (len - 1);
|
||||
|
@ -35,15 +35,22 @@ typedef struct {
|
||||
01000000 - invalid code
|
||||
*/
|
||||
|
||||
/* Maximum size of dynamic tree. The maximum found in a long but non-
|
||||
exhaustive search was 1444 code structures (852 for length/literals
|
||||
and 592 for distances, the latter actually the result of an
|
||||
exhaustive search). The true maximum is not known, but the value
|
||||
below is more than safe. */
|
||||
#define ENOUGH 2048
|
||||
#define MAXD 592
|
||||
/* Maximum size of the dynamic table. The maximum number of code structures is
|
||||
1444, which is the sum of 852 for literal/length codes and 592 for distance
|
||||
codes. These values were found by exhaustive searches using the program
|
||||
examples/enough.c found in the zlib distribtution. The arguments to that
|
||||
program are the number of symbols, the initial root table size, and the
|
||||
maximum bit length of a code. "enough 286 9 15" for literal/length codes
|
||||
returns returns 852, and "enough 30 6 15" for distance codes returns 592.
|
||||
The initial root table size (9 or 6) is found in the fifth argument of the
|
||||
inflate_table() calls in inflate.c and infback.c. If the root table size is
|
||||
changed, then these maximum sizes would be need to be recalculated and
|
||||
updated. */
|
||||
#define ENOUGH_LENS 852
|
||||
#define ENOUGH_DISTS 592
|
||||
#define ENOUGH (ENOUGH_LENS+ENOUGH_DISTS)
|
||||
|
||||
/* Type of code to build for inftable() */
|
||||
/* Type of code to build for inflate_table() */
|
||||
typedef enum {
|
||||
CODES,
|
||||
LENS,
|
||||
|
@ -1,5 +1,5 @@
|
||||
/* minigzip.c -- simulate gzip using the zlib compression library
|
||||
* Copyright (C) 1995-2005 Jean-loup Gailly.
|
||||
* Copyright (C) 1995-2006, 2010 Jean-loup Gailly.
|
||||
* For conditions of distribution and use, see copyright notice in zlib.h
|
||||
*/
|
||||
|
||||
@ -13,11 +13,10 @@
|
||||
* or in pipe mode.
|
||||
*/
|
||||
|
||||
#include <sys/cdefs.h>
|
||||
__FBSDID("$FreeBSD$");
|
||||
/* @(#) $Id$ */
|
||||
|
||||
#include <stdio.h>
|
||||
#include "zlib.h"
|
||||
#include <stdio.h>
|
||||
|
||||
#ifdef STDC
|
||||
# include <string.h>
|
||||
@ -55,6 +54,70 @@ __FBSDID("$FreeBSD$");
|
||||
extern int unlink OF((const char *));
|
||||
#endif
|
||||
|
||||
#if defined(UNDER_CE) && defined(NO_ERRNO_H)
|
||||
# include <windows.h>
|
||||
# define perror(s) pwinerror(s)
|
||||
|
||||
/* Map the Windows error number in ERROR to a locale-dependent error
|
||||
message string and return a pointer to it. Typically, the values
|
||||
for ERROR come from GetLastError.
|
||||
|
||||
The string pointed to shall not be modified by the application,
|
||||
but may be overwritten by a subsequent call to strwinerror
|
||||
|
||||
The strwinerror function does not change the current setting
|
||||
of GetLastError. */
|
||||
|
||||
static char *strwinerror (error)
|
||||
DWORD error;
|
||||
{
|
||||
static char buf[1024];
|
||||
|
||||
wchar_t *msgbuf;
|
||||
DWORD lasterr = GetLastError();
|
||||
DWORD chars = FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM
|
||||
| FORMAT_MESSAGE_ALLOCATE_BUFFER,
|
||||
NULL,
|
||||
error,
|
||||
0, /* Default language */
|
||||
(LPVOID)&msgbuf,
|
||||
0,
|
||||
NULL);
|
||||
if (chars != 0) {
|
||||
/* If there is an \r\n appended, zap it. */
|
||||
if (chars >= 2
|
||||
&& msgbuf[chars - 2] == '\r' && msgbuf[chars - 1] == '\n') {
|
||||
chars -= 2;
|
||||
msgbuf[chars] = 0;
|
||||
}
|
||||
|
||||
if (chars > sizeof (buf) - 1) {
|
||||
chars = sizeof (buf) - 1;
|
||||
msgbuf[chars] = 0;
|
||||
}
|
||||
|
||||
wcstombs(buf, msgbuf, chars + 1);
|
||||
LocalFree(msgbuf);
|
||||
}
|
||||
else {
|
||||
sprintf(buf, "unknown win32 error (%ld)", error);
|
||||
}
|
||||
|
||||
SetLastError(lasterr);
|
||||
return buf;
|
||||
}
|
||||
|
||||
static void pwinerror (s)
|
||||
const char *s;
|
||||
{
|
||||
if (s && *s)
|
||||
fprintf(stderr, "%s: %s\n", s, strwinerror(GetLastError ()));
|
||||
else
|
||||
fprintf(stderr, "%s\n", strwinerror(GetLastError ()));
|
||||
}
|
||||
|
||||
#endif /* UNDER_CE && NO_ERRNO_H */
|
||||
|
||||
#ifndef GZ_SUFFIX
|
||||
# define GZ_SUFFIX ".gz"
|
||||
#endif
|
||||
@ -201,9 +264,9 @@ void file_compress(file, mode)
|
||||
|
||||
if (strlen(file) + strlen(GZ_SUFFIX) >= sizeof(outfile)) {
|
||||
fprintf(stderr, "%s: filename too long\n", prog);
|
||||
exit(1);
|
||||
exit(1);
|
||||
}
|
||||
|
||||
|
||||
strcpy(outfile, file);
|
||||
strcat(outfile, GZ_SUFFIX);
|
||||
|
||||
@ -237,7 +300,7 @@ void file_uncompress(file)
|
||||
|
||||
if (len + strlen(GZ_SUFFIX) >= sizeof(buf)) {
|
||||
fprintf(stderr, "%s: filename too long\n", prog);
|
||||
exit(1);
|
||||
exit(1);
|
||||
}
|
||||
|
||||
strcpy(buf, file);
|
||||
@ -304,9 +367,9 @@ int main(argc, argv)
|
||||
|
||||
while (argc > 0) {
|
||||
if (strcmp(*argv, "-c") == 0)
|
||||
copyout = 1;
|
||||
copyout = 1;
|
||||
else if (strcmp(*argv, "-d") == 0)
|
||||
uncompr = 1;
|
||||
uncompr = 1;
|
||||
else if (strcmp(*argv, "-f") == 0)
|
||||
outmode[3] = 'f';
|
||||
else if (strcmp(*argv, "-h") == 0)
|
||||
@ -335,36 +398,36 @@ int main(argc, argv)
|
||||
gz_compress(stdin, file);
|
||||
}
|
||||
} else {
|
||||
if (copyout) {
|
||||
SET_BINARY_MODE(stdout);
|
||||
}
|
||||
if (copyout) {
|
||||
SET_BINARY_MODE(stdout);
|
||||
}
|
||||
do {
|
||||
if (uncompr) {
|
||||
if (copyout) {
|
||||
file = gzopen(*argv, "rb");
|
||||
if (file == NULL)
|
||||
fprintf(stderr, "%s: can't gzopen %s\n", prog, *argv);
|
||||
else
|
||||
gz_uncompress(file, stdout);
|
||||
} else {
|
||||
file_uncompress(*argv);
|
||||
}
|
||||
if (copyout) {
|
||||
file = gzopen(*argv, "rb");
|
||||
if (file == NULL)
|
||||
fprintf(stderr, "%s: can't gzopen %s\n", prog, *argv);
|
||||
else
|
||||
gz_uncompress(file, stdout);
|
||||
} else {
|
||||
file_uncompress(*argv);
|
||||
}
|
||||
} else {
|
||||
if (copyout) {
|
||||
FILE * in = fopen(*argv, "rb");
|
||||
if (copyout) {
|
||||
FILE * in = fopen(*argv, "rb");
|
||||
|
||||
if (in == NULL) {
|
||||
perror(*argv);
|
||||
} else {
|
||||
file = gzdopen(fileno(stdout), outmode);
|
||||
if (file == NULL) error("can't gzdopen stdout");
|
||||
if (in == NULL) {
|
||||
perror(*argv);
|
||||
} else {
|
||||
file = gzdopen(fileno(stdout), outmode);
|
||||
if (file == NULL) error("can't gzdopen stdout");
|
||||
|
||||
gz_compress(in, file);
|
||||
}
|
||||
|
||||
} else {
|
||||
file_compress(*argv, outmode);
|
||||
}
|
||||
gz_compress(in, file);
|
||||
}
|
||||
|
||||
} else {
|
||||
file_compress(*argv, outmode);
|
||||
}
|
||||
}
|
||||
} while (argv++, --argc);
|
||||
}
|
||||
|
@ -1,5 +1,6 @@
|
||||
/* trees.c -- output deflated data using Huffman coding
|
||||
* Copyright (C) 1995-2005 Jean-loup Gailly
|
||||
* Copyright (C) 1995-2009 Jean-loup Gailly
|
||||
* detect_data_type() function provided freely by Cosmin Truta, 2006
|
||||
* For conditions of distribution and use, see copyright notice in zlib.h
|
||||
*/
|
||||
|
||||
@ -152,7 +153,7 @@ local void send_all_trees OF((deflate_state *s, int lcodes, int dcodes,
|
||||
int blcodes));
|
||||
local void compress_block OF((deflate_state *s, ct_data *ltree,
|
||||
ct_data *dtree));
|
||||
local void set_data_type OF((deflate_state *s));
|
||||
local int detect_data_type OF((deflate_state *s));
|
||||
local unsigned bi_reverse OF((unsigned value, int length));
|
||||
local void bi_windup OF((deflate_state *s));
|
||||
local void bi_flush OF((deflate_state *s));
|
||||
@ -203,12 +204,12 @@ local void send_bits(s, value, length)
|
||||
* unused bits in value.
|
||||
*/
|
||||
if (s->bi_valid > (int)Buf_size - length) {
|
||||
s->bi_buf |= (value << s->bi_valid);
|
||||
s->bi_buf |= (ush)value << s->bi_valid;
|
||||
put_short(s, s->bi_buf);
|
||||
s->bi_buf = (ush)value >> (Buf_size - s->bi_valid);
|
||||
s->bi_valid += length - Buf_size;
|
||||
} else {
|
||||
s->bi_buf |= value << s->bi_valid;
|
||||
s->bi_buf |= (ush)value << s->bi_valid;
|
||||
s->bi_valid += length;
|
||||
}
|
||||
}
|
||||
@ -218,12 +219,12 @@ local void send_bits(s, value, length)
|
||||
{ int len = length;\
|
||||
if (s->bi_valid > (int)Buf_size - len) {\
|
||||
int val = value;\
|
||||
s->bi_buf |= (val << s->bi_valid);\
|
||||
s->bi_buf |= (ush)val << s->bi_valid;\
|
||||
put_short(s, s->bi_buf);\
|
||||
s->bi_buf = (ush)val >> (Buf_size - s->bi_valid);\
|
||||
s->bi_valid += len - Buf_size;\
|
||||
} else {\
|
||||
s->bi_buf |= (value) << s->bi_valid;\
|
||||
s->bi_buf |= (ush)(value) << s->bi_valid;\
|
||||
s->bi_valid += len;\
|
||||
}\
|
||||
}
|
||||
@ -250,11 +251,13 @@ local void tr_static_init()
|
||||
if (static_init_done) return;
|
||||
|
||||
/* For some embedded targets, global variables are not initialized: */
|
||||
#ifdef NO_INIT_GLOBAL_POINTERS
|
||||
static_l_desc.static_tree = static_ltree;
|
||||
static_l_desc.extra_bits = extra_lbits;
|
||||
static_d_desc.static_tree = static_dtree;
|
||||
static_d_desc.extra_bits = extra_dbits;
|
||||
static_bl_desc.extra_bits = extra_blbits;
|
||||
#endif
|
||||
|
||||
/* Initialize the mapping length (0..255) -> length code (0..28) */
|
||||
length = 0;
|
||||
@ -864,13 +867,13 @@ local void send_all_trees(s, lcodes, dcodes, blcodes)
|
||||
/* ===========================================================================
|
||||
* Send a stored block
|
||||
*/
|
||||
void _tr_stored_block(s, buf, stored_len, eof)
|
||||
void _tr_stored_block(s, buf, stored_len, last)
|
||||
deflate_state *s;
|
||||
charf *buf; /* input block */
|
||||
ulg stored_len; /* length of input block */
|
||||
int eof; /* true if this is the last block for a file */
|
||||
int last; /* one if this is the last block for a file */
|
||||
{
|
||||
send_bits(s, (STORED_BLOCK<<1)+eof, 3); /* send block type */
|
||||
send_bits(s, (STORED_BLOCK<<1)+last, 3); /* send block type */
|
||||
#ifdef DEBUG
|
||||
s->compressed_len = (s->compressed_len + 3 + 7) & (ulg)~7L;
|
||||
s->compressed_len += (stored_len + 4) << 3;
|
||||
@ -918,11 +921,11 @@ void _tr_align(s)
|
||||
* Determine the best encoding for the current block: dynamic trees, static
|
||||
* trees or store, and output the encoded block to the zip file.
|
||||
*/
|
||||
void _tr_flush_block(s, buf, stored_len, eof)
|
||||
void _tr_flush_block(s, buf, stored_len, last)
|
||||
deflate_state *s;
|
||||
charf *buf; /* input block, or NULL if too old */
|
||||
ulg stored_len; /* length of input block */
|
||||
int eof; /* true if this is the last block for a file */
|
||||
int last; /* one if this is the last block for a file */
|
||||
{
|
||||
ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */
|
||||
int max_blindex = 0; /* index of last bit length code of non zero freq */
|
||||
@ -931,8 +934,8 @@ void _tr_flush_block(s, buf, stored_len, eof)
|
||||
if (s->level > 0) {
|
||||
|
||||
/* Check if the file is binary or text */
|
||||
if (stored_len > 0 && s->strm->data_type == Z_UNKNOWN)
|
||||
set_data_type(s);
|
||||
if (s->strm->data_type == Z_UNKNOWN)
|
||||
s->strm->data_type = detect_data_type(s);
|
||||
|
||||
/* Construct the literal and distance trees */
|
||||
build_tree(s, (tree_desc *)(&(s->l_desc)));
|
||||
@ -978,20 +981,20 @@ void _tr_flush_block(s, buf, stored_len, eof)
|
||||
* successful. If LIT_BUFSIZE <= WSIZE, it is never too late to
|
||||
* transform a block into a stored block.
|
||||
*/
|
||||
_tr_stored_block(s, buf, stored_len, eof);
|
||||
_tr_stored_block(s, buf, stored_len, last);
|
||||
|
||||
#ifdef FORCE_STATIC
|
||||
} else if (static_lenb >= 0) { /* force static trees */
|
||||
#else
|
||||
} else if (s->strategy == Z_FIXED || static_lenb == opt_lenb) {
|
||||
#endif
|
||||
send_bits(s, (STATIC_TREES<<1)+eof, 3);
|
||||
send_bits(s, (STATIC_TREES<<1)+last, 3);
|
||||
compress_block(s, (ct_data *)static_ltree, (ct_data *)static_dtree);
|
||||
#ifdef DEBUG
|
||||
s->compressed_len += 3 + s->static_len;
|
||||
#endif
|
||||
} else {
|
||||
send_bits(s, (DYN_TREES<<1)+eof, 3);
|
||||
send_bits(s, (DYN_TREES<<1)+last, 3);
|
||||
send_all_trees(s, s->l_desc.max_code+1, s->d_desc.max_code+1,
|
||||
max_blindex+1);
|
||||
compress_block(s, (ct_data *)s->dyn_ltree, (ct_data *)s->dyn_dtree);
|
||||
@ -1005,14 +1008,14 @@ void _tr_flush_block(s, buf, stored_len, eof)
|
||||
*/
|
||||
init_block(s);
|
||||
|
||||
if (eof) {
|
||||
if (last) {
|
||||
bi_windup(s);
|
||||
#ifdef DEBUG
|
||||
s->compressed_len += 7; /* align on byte boundary */
|
||||
#endif
|
||||
}
|
||||
Tracev((stderr,"\ncomprlen %lu(%lu) ", s->compressed_len>>3,
|
||||
s->compressed_len-7*eof));
|
||||
s->compressed_len-7*last));
|
||||
}
|
||||
|
||||
/* ===========================================================================
|
||||
@ -1118,24 +1121,45 @@ local void compress_block(s, ltree, dtree)
|
||||
}
|
||||
|
||||
/* ===========================================================================
|
||||
* Set the data type to BINARY or TEXT, using a crude approximation:
|
||||
* set it to Z_TEXT if all symbols are either printable characters (33 to 255)
|
||||
* or white spaces (9 to 13, or 32); or set it to Z_BINARY otherwise.
|
||||
* Check if the data type is TEXT or BINARY, using the following algorithm:
|
||||
* - TEXT if the two conditions below are satisfied:
|
||||
* a) There are no non-portable control characters belonging to the
|
||||
* "black list" (0..6, 14..25, 28..31).
|
||||
* b) There is at least one printable character belonging to the
|
||||
* "white list" (9 {TAB}, 10 {LF}, 13 {CR}, 32..255).
|
||||
* - BINARY otherwise.
|
||||
* - The following partially-portable control characters form a
|
||||
* "gray list" that is ignored in this detection algorithm:
|
||||
* (7 {BEL}, 8 {BS}, 11 {VT}, 12 {FF}, 26 {SUB}, 27 {ESC}).
|
||||
* IN assertion: the fields Freq of dyn_ltree are set.
|
||||
*/
|
||||
local void set_data_type(s)
|
||||
local int detect_data_type(s)
|
||||
deflate_state *s;
|
||||
{
|
||||
/* black_mask is the bit mask of black-listed bytes
|
||||
* set bits 0..6, 14..25, and 28..31
|
||||
* 0xf3ffc07f = binary 11110011111111111100000001111111
|
||||
*/
|
||||
unsigned long black_mask = 0xf3ffc07fUL;
|
||||
int n;
|
||||
|
||||
for (n = 0; n < 9; n++)
|
||||
/* Check for non-textual ("black-listed") bytes. */
|
||||
for (n = 0; n <= 31; n++, black_mask >>= 1)
|
||||
if ((black_mask & 1) && (s->dyn_ltree[n].Freq != 0))
|
||||
return Z_BINARY;
|
||||
|
||||
/* Check for textual ("white-listed") bytes. */
|
||||
if (s->dyn_ltree[9].Freq != 0 || s->dyn_ltree[10].Freq != 0
|
||||
|| s->dyn_ltree[13].Freq != 0)
|
||||
return Z_TEXT;
|
||||
for (n = 32; n < LITERALS; n++)
|
||||
if (s->dyn_ltree[n].Freq != 0)
|
||||
break;
|
||||
if (n == 9)
|
||||
for (n = 14; n < 32; n++)
|
||||
if (s->dyn_ltree[n].Freq != 0)
|
||||
break;
|
||||
s->strm->data_type = (n == 32) ? Z_TEXT : Z_BINARY;
|
||||
return Z_TEXT;
|
||||
|
||||
/* There are no "black-listed" or "white-listed" bytes:
|
||||
* this stream either is empty or has tolerated ("gray-listed") bytes only.
|
||||
*/
|
||||
return Z_BINARY;
|
||||
}
|
||||
|
||||
/* ===========================================================================
|
||||
|
@ -1,5 +1,5 @@
|
||||
/* uncompr.c -- decompress a memory buffer
|
||||
* Copyright (C) 1995-2003 Jean-loup Gailly.
|
||||
* Copyright (C) 1995-2003, 2010 Jean-loup Gailly.
|
||||
* For conditions of distribution and use, see copyright notice in zlib.h
|
||||
*/
|
||||
|
||||
@ -16,8 +16,6 @@
|
||||
been saved previously by the compressor and transmitted to the decompressor
|
||||
by some mechanism outside the scope of this compression library.)
|
||||
Upon exit, destLen is the actual size of the compressed buffer.
|
||||
This function can be used to decompress a whole file at once if the
|
||||
input file is mmap'ed.
|
||||
|
||||
uncompress returns Z_OK if success, Z_MEM_ERROR if there was not
|
||||
enough memory, Z_BUF_ERROR if there was not enough room in the output
|
||||
|
205
lib/libz/zconf.h
205
lib/libz/zconf.h
@ -1,5 +1,5 @@
|
||||
/* zconf.h -- configuration of the zlib compression library
|
||||
* Copyright (C) 1995-2005 Jean-loup Gailly.
|
||||
* Copyright (C) 1995-2010 Jean-loup Gailly.
|
||||
* For conditions of distribution and use, see copyright notice in zlib.h
|
||||
*/
|
||||
|
||||
@ -11,52 +11,124 @@
|
||||
/*
|
||||
* If you *really* need a unique prefix for all types and library functions,
|
||||
* compile with -DZ_PREFIX. The "standard" zlib should be compiled without it.
|
||||
* Even better than compiling with -DZ_PREFIX would be to use configure to set
|
||||
* this permanently in zconf.h using "./configure --zprefix".
|
||||
*/
|
||||
#ifdef Z_PREFIX
|
||||
# define deflateInit_ z_deflateInit_
|
||||
# define deflate z_deflate
|
||||
# define deflateEnd z_deflateEnd
|
||||
# define inflateInit_ z_inflateInit_
|
||||
# define inflate z_inflate
|
||||
# define inflateEnd z_inflateEnd
|
||||
# define deflateInit2_ z_deflateInit2_
|
||||
# define deflateSetDictionary z_deflateSetDictionary
|
||||
# define deflateCopy z_deflateCopy
|
||||
# define deflateReset z_deflateReset
|
||||
# define deflateParams z_deflateParams
|
||||
# define deflateBound z_deflateBound
|
||||
# define deflatePrime z_deflatePrime
|
||||
# define inflateInit2_ z_inflateInit2_
|
||||
# define inflateSetDictionary z_inflateSetDictionary
|
||||
# define inflateSync z_inflateSync
|
||||
# define inflateSyncPoint z_inflateSyncPoint
|
||||
# define inflateCopy z_inflateCopy
|
||||
# define inflateReset z_inflateReset
|
||||
# define inflateBack z_inflateBack
|
||||
# define inflateBackEnd z_inflateBackEnd
|
||||
#ifdef Z_PREFIX /* may be set to #if 1 by ./configure */
|
||||
|
||||
/* all linked symbols */
|
||||
# define _dist_code z__dist_code
|
||||
# define _length_code z__length_code
|
||||
# define _tr_align z__tr_align
|
||||
# define _tr_flush_block z__tr_flush_block
|
||||
# define _tr_init z__tr_init
|
||||
# define _tr_stored_block z__tr_stored_block
|
||||
# define _tr_tally z__tr_tally
|
||||
# define adler32 z_adler32
|
||||
# define adler32_combine z_adler32_combine
|
||||
# define adler32_combine64 z_adler32_combine64
|
||||
# define compress z_compress
|
||||
# define compress2 z_compress2
|
||||
# define compressBound z_compressBound
|
||||
# define uncompress z_uncompress
|
||||
# define adler32 z_adler32
|
||||
# define crc32 z_crc32
|
||||
# define crc32_combine z_crc32_combine
|
||||
# define crc32_combine64 z_crc32_combine64
|
||||
# define deflate z_deflate
|
||||
# define deflateBound z_deflateBound
|
||||
# define deflateCopy z_deflateCopy
|
||||
# define deflateEnd z_deflateEnd
|
||||
# define deflateInit2_ z_deflateInit2_
|
||||
# define deflateInit_ z_deflateInit_
|
||||
# define deflateParams z_deflateParams
|
||||
# define deflatePrime z_deflatePrime
|
||||
# define deflateReset z_deflateReset
|
||||
# define deflateSetDictionary z_deflateSetDictionary
|
||||
# define deflateSetHeader z_deflateSetHeader
|
||||
# define deflateTune z_deflateTune
|
||||
# define deflate_copyright z_deflate_copyright
|
||||
# define get_crc_table z_get_crc_table
|
||||
# define gz_error z_gz_error
|
||||
# define gz_intmax z_gz_intmax
|
||||
# define gz_strwinerror z_gz_strwinerror
|
||||
# define gzbuffer z_gzbuffer
|
||||
# define gzclearerr z_gzclearerr
|
||||
# define gzclose z_gzclose
|
||||
# define gzclose_r z_gzclose_r
|
||||
# define gzclose_w z_gzclose_w
|
||||
# define gzdirect z_gzdirect
|
||||
# define gzdopen z_gzdopen
|
||||
# define gzeof z_gzeof
|
||||
# define gzerror z_gzerror
|
||||
# define gzflush z_gzflush
|
||||
# define gzgetc z_gzgetc
|
||||
# define gzgets z_gzgets
|
||||
# define gzoffset z_gzoffset
|
||||
# define gzoffset64 z_gzoffset64
|
||||
# define gzopen z_gzopen
|
||||
# define gzopen64 z_gzopen64
|
||||
# define gzprintf z_gzprintf
|
||||
# define gzputc z_gzputc
|
||||
# define gzputs z_gzputs
|
||||
# define gzread z_gzread
|
||||
# define gzrewind z_gzrewind
|
||||
# define gzseek z_gzseek
|
||||
# define gzseek64 z_gzseek64
|
||||
# define gzsetparams z_gzsetparams
|
||||
# define gztell z_gztell
|
||||
# define gztell64 z_gztell64
|
||||
# define gzungetc z_gzungetc
|
||||
# define gzwrite z_gzwrite
|
||||
# define inflate z_inflate
|
||||
# define inflateBack z_inflateBack
|
||||
# define inflateBackEnd z_inflateBackEnd
|
||||
# define inflateBackInit_ z_inflateBackInit_
|
||||
# define inflateCopy z_inflateCopy
|
||||
# define inflateEnd z_inflateEnd
|
||||
# define inflateGetHeader z_inflateGetHeader
|
||||
# define inflateInit2_ z_inflateInit2_
|
||||
# define inflateInit_ z_inflateInit_
|
||||
# define inflateMark z_inflateMark
|
||||
# define inflatePrime z_inflatePrime
|
||||
# define inflateReset z_inflateReset
|
||||
# define inflateReset2 z_inflateReset2
|
||||
# define inflateSetDictionary z_inflateSetDictionary
|
||||
# define inflateSync z_inflateSync
|
||||
# define inflateSyncPoint z_inflateSyncPoint
|
||||
# define inflateUndermine z_inflateUndermine
|
||||
# define inflate_copyright z_inflate_copyright
|
||||
# define inflate_fast z_inflate_fast
|
||||
# define inflate_table z_inflate_table
|
||||
# define uncompress z_uncompress
|
||||
# define zError z_zError
|
||||
# define zcalloc z_zcalloc
|
||||
# define zcfree z_zcfree
|
||||
# define zlibCompileFlags z_zlibCompileFlags
|
||||
# define zlibVersion z_zlibVersion
|
||||
|
||||
# define alloc_func z_alloc_func
|
||||
# define free_func z_free_func
|
||||
# define in_func z_in_func
|
||||
# define out_func z_out_func
|
||||
/* all zlib typedefs in zlib.h and zconf.h */
|
||||
# define Byte z_Byte
|
||||
# define uInt z_uInt
|
||||
# define uLong z_uLong
|
||||
# define Bytef z_Bytef
|
||||
# define alloc_func z_alloc_func
|
||||
# define charf z_charf
|
||||
# define free_func z_free_func
|
||||
# define gzFile z_gzFile
|
||||
# define gz_header z_gz_header
|
||||
# define gz_headerp z_gz_headerp
|
||||
# define in_func z_in_func
|
||||
# define intf z_intf
|
||||
# define out_func z_out_func
|
||||
# define uInt z_uInt
|
||||
# define uIntf z_uIntf
|
||||
# define uLong z_uLong
|
||||
# define uLongf z_uLongf
|
||||
# define voidpf z_voidpf
|
||||
# define voidp z_voidp
|
||||
# define voidpc z_voidpc
|
||||
# define voidpf z_voidpf
|
||||
|
||||
/* all zlib structs in zlib.h and zconf.h */
|
||||
# define gz_header_s z_gz_header_s
|
||||
# define internal_state z_internal_state
|
||||
|
||||
#endif
|
||||
|
||||
#if defined(__MSDOS__) && !defined(MSDOS)
|
||||
@ -243,6 +315,10 @@
|
||||
# endif
|
||||
#endif
|
||||
|
||||
#ifdef HAVE_VISIBILITY_PRAGMA
|
||||
# define ZEXTERN __attribute__((visibility ("default"))) extern
|
||||
#endif
|
||||
|
||||
#ifndef ZEXTERN
|
||||
# define ZEXTERN extern
|
||||
#endif
|
||||
@ -284,14 +360,25 @@ typedef uLong FAR uLongf;
|
||||
typedef Byte *voidp;
|
||||
#endif
|
||||
|
||||
#if 0 /* HAVE_UNISTD_H -- this line is updated by ./configure */
|
||||
# include <sys/types.h> /* for off_t */
|
||||
# include <unistd.h> /* for SEEK_* and off_t */
|
||||
# ifdef VMS
|
||||
# include <unixio.h> /* for off_t */
|
||||
# endif
|
||||
# define z_off_t off_t
|
||||
#if 0 /* was set to #if 0 by ./configure */
|
||||
# define Z_HAVE_UNISTD_H
|
||||
#endif
|
||||
|
||||
#ifdef Z_HAVE_UNISTD_H
|
||||
# include <sys/types.h> /* for off_t */
|
||||
# include <unistd.h> /* for SEEK_* and off_t */
|
||||
# ifdef VMS
|
||||
# include <unixio.h> /* for off_t */
|
||||
# endif
|
||||
# ifndef z_off_t
|
||||
# define z_off_t off_t
|
||||
# endif
|
||||
#endif
|
||||
|
||||
#ifdef _LARGEFILE64_SOURCE
|
||||
# include <sys/types.h>
|
||||
#endif
|
||||
|
||||
#ifndef SEEK_SET
|
||||
# define SEEK_SET 0 /* Seek from beginning of file. */
|
||||
# define SEEK_CUR 1 /* Seek from current position. */
|
||||
@ -299,12 +386,13 @@ typedef uLong FAR uLongf;
|
||||
#endif
|
||||
|
||||
/*
|
||||
* This is hard-configured for FreeBSD, since zlib doesn't actually support
|
||||
* using the system off_t for offsets unless off_t is no longer than long.
|
||||
* To minimize the diff, we just "undef z_off_t" rather than modifying
|
||||
* the following lines.
|
||||
* This is hard-configured for FreeBSD.
|
||||
*/
|
||||
#undef z_off_t
|
||||
#include <sys/types.h>
|
||||
#define z_off_t off_t
|
||||
#ifndef _FILE_OFFSET_BITS
|
||||
#define _FILE_OFFSET_BITS 64
|
||||
#endif
|
||||
|
||||
#ifndef z_off_t
|
||||
# define z_off_t long
|
||||
@ -316,26 +404,23 @@ typedef uLong FAR uLongf;
|
||||
|
||||
#if defined(__MVS__)
|
||||
# define NO_vsnprintf
|
||||
# ifdef FAR
|
||||
# undef FAR
|
||||
# endif
|
||||
#endif
|
||||
|
||||
/* MVS linker does not support external names larger than 8 bytes */
|
||||
#if defined(__MVS__)
|
||||
# pragma map(deflateInit_,"DEIN")
|
||||
# pragma map(deflateInit2_,"DEIN2")
|
||||
# pragma map(deflateEnd,"DEEND")
|
||||
# pragma map(deflateBound,"DEBND")
|
||||
# pragma map(inflateInit_,"ININ")
|
||||
# pragma map(inflateInit2_,"ININ2")
|
||||
# pragma map(inflateEnd,"INEND")
|
||||
# pragma map(inflateSync,"INSY")
|
||||
# pragma map(inflateSetDictionary,"INSEDI")
|
||||
# pragma map(compressBound,"CMBND")
|
||||
# pragma map(inflate_table,"INTABL")
|
||||
# pragma map(inflate_fast,"INFA")
|
||||
# pragma map(inflate_copyright,"INCOPY")
|
||||
#pragma map(deflateInit_,"DEIN")
|
||||
#pragma map(deflateInit2_,"DEIN2")
|
||||
#pragma map(deflateEnd,"DEEND")
|
||||
#pragma map(deflateBound,"DEBND")
|
||||
#pragma map(inflateInit_,"ININ")
|
||||
#pragma map(inflateInit2_,"ININ2")
|
||||
#pragma map(inflateEnd,"INEND")
|
||||
#pragma map(inflateSync,"INSY")
|
||||
#pragma map(inflateSetDictionary,"INSEDI")
|
||||
#pragma map(compressBound,"CMBND")
|
||||
#pragma map(inflate_table,"INTABL")
|
||||
#pragma map(inflate_fast,"INFA")
|
||||
#pragma map(inflate_copyright,"INCOPY")
|
||||
#endif
|
||||
|
||||
#endif /* ZCONF_H */
|
||||
|
@ -1,4 +1,4 @@
|
||||
.TH ZLIB 3 "18 July 2005"
|
||||
.TH ZLIB 3 "14 March 2010"
|
||||
.SH NAME
|
||||
zlib \- compression/decompression library
|
||||
.SH SYNOPSIS
|
||||
@ -9,15 +9,15 @@ for full description]
|
||||
The
|
||||
.I zlib
|
||||
library is a general purpose data compression library.
|
||||
The code is thread safe.
|
||||
The code is thread safe, assuming that the standard library functions
|
||||
used are thread safe, such as memory allocation routines.
|
||||
It provides in-memory compression and decompression functions,
|
||||
including integrity checks of the uncompressed data.
|
||||
This version of the library supports only one compression method (deflation)
|
||||
but other algorithms will be added later
|
||||
and will have the same stream interface.
|
||||
but other algorithms may be added later
|
||||
with the same stream interface.
|
||||
.LP
|
||||
Compression can be done in a single step if the buffers are large enough
|
||||
(for example if an input file is mmap'ed),
|
||||
or can be done by repeated calls of the compression function.
|
||||
In the latter case,
|
||||
the application must provide more input and/or consume the output
|
||||
@ -30,7 +30,7 @@ with an interface similar to that of stdio.
|
||||
.LP
|
||||
The library does not install any signal handler.
|
||||
The decoder checks the consistency of the compressed data,
|
||||
so the library should never crash even in case of corrupted input.
|
||||
so the library should never crash even in the case of corrupted input.
|
||||
.LP
|
||||
All functions of the compression library are documented in the file
|
||||
.IR zlib.h .
|
||||
@ -38,18 +38,19 @@ The distribution source includes examples of use of the library
|
||||
in the files
|
||||
.I example.c
|
||||
and
|
||||
.IR minigzip.c .
|
||||
.IR minigzip.c,
|
||||
as well as other examples in the
|
||||
.IR examples/
|
||||
directory.
|
||||
.LP
|
||||
Changes to this version are documented in the file
|
||||
.I ChangeLog
|
||||
that accompanies the source,
|
||||
and are concerned primarily with bug fixes and portability enhancements.
|
||||
that accompanies the source.
|
||||
.LP
|
||||
A Java implementation of
|
||||
.I zlib
|
||||
is available in the Java Development Kit 1.1:
|
||||
is available in Java using the java.util.zip package:
|
||||
.IP
|
||||
http://www.javasoft.com/products/JDK/1.1/docs/api/Package-java.util.zip.html
|
||||
http://java.sun.com/developer/technicalArticles/Programming/compression/
|
||||
.LP
|
||||
A Perl interface to
|
||||
.IR zlib ,
|
||||
@ -57,7 +58,7 @@ written by Paul Marquess (pmqs@cpan.org),
|
||||
is available at CPAN (Comprehensive Perl Archive Network) sites,
|
||||
including:
|
||||
.IP
|
||||
http://www.cpan.org/modules/by-module/Compress/
|
||||
http://search.cpan.org/~pmqs/IO-Compress-Zlib/
|
||||
.LP
|
||||
A Python interface to
|
||||
.IR zlib ,
|
||||
@ -66,14 +67,11 @@ is available in Python 1.5 and later versions:
|
||||
.IP
|
||||
http://www.python.org/doc/lib/module-zlib.html
|
||||
.LP
|
||||
A
|
||||
.I zlib
|
||||
binding for
|
||||
.IR tcl (1),
|
||||
written by Andreas Kupries (a.kupries@westend.com),
|
||||
is availlable at:
|
||||
is built into
|
||||
.IR tcl:
|
||||
.IP
|
||||
http://www.westend.com/~kupries/doc/trf/man/man.html
|
||||
http://wiki.tcl.tk/4610
|
||||
.LP
|
||||
An experimental package to read and write files in .zip format,
|
||||
written on top of
|
||||
@ -81,40 +79,34 @@ written on top of
|
||||
by Gilles Vollant (info@winimage.com),
|
||||
is available at:
|
||||
.IP
|
||||
http://www.winimage.com/zLibDll/unzip.html
|
||||
http://www.winimage.com/zLibDll/minizip.html
|
||||
and also in the
|
||||
.I contrib/minizip
|
||||
directory of the main
|
||||
.I zlib
|
||||
web site.
|
||||
source distribution.
|
||||
.SH "SEE ALSO"
|
||||
The
|
||||
.I zlib
|
||||
web site can be found at either of these locations:
|
||||
web site can be found at:
|
||||
.IP
|
||||
http://www.zlib.org
|
||||
.br
|
||||
http://www.gzip.org/zlib/
|
||||
http://zlib.net/
|
||||
.LP
|
||||
The data format used by the zlib library is described by RFC
|
||||
(Request for Comments) 1950 to 1952 in the files:
|
||||
.IP
|
||||
http://www.ietf.org/rfc/rfc1950.txt (concerning zlib format)
|
||||
http://www.ietf.org/rfc/rfc1950.txt (for the zlib header and trailer format)
|
||||
.br
|
||||
http://www.ietf.org/rfc/rfc1951.txt (concerning deflate format)
|
||||
http://www.ietf.org/rfc/rfc1951.txt (for the deflate compressed data format)
|
||||
.br
|
||||
http://www.ietf.org/rfc/rfc1952.txt (concerning gzip format)
|
||||
http://www.ietf.org/rfc/rfc1952.txt (for the gzip header and trailer format)
|
||||
.LP
|
||||
These documents are also available in other formats from:
|
||||
.IP
|
||||
ftp://ftp.uu.net/graphics/png/documents/zlib/zdoc-index.html
|
||||
.LP
|
||||
Mark Nelson (markn@ieee.org) wrote an article about
|
||||
Mark Nelson wrote an article about
|
||||
.I zlib
|
||||
for the Jan. 1997 issue of Dr. Dobb's Journal;
|
||||
a copy of the article is available at:
|
||||
.IP
|
||||
http://dogma.net/markn/articles/zlibtool/zlibtool.htm
|
||||
http://marknelson.us/1997/01/01/zlib-engine/
|
||||
.SH "REPORTING PROBLEMS"
|
||||
Before reporting a problem,
|
||||
please check the
|
||||
@ -127,14 +119,14 @@ Please read the
|
||||
.I zlib
|
||||
FAQ at:
|
||||
.IP
|
||||
http://www.gzip.org/zlib/zlib_faq.html
|
||||
http://zlib.net/zlib_faq.html
|
||||
.LP
|
||||
before asking for help.
|
||||
Send questions and/or comments to zlib@gzip.org,
|
||||
or (for the Windows DLL version) to Gilles Vollant (info@winimage.com).
|
||||
.SH AUTHORS
|
||||
Version 1.2.3
|
||||
Copyright (C) 1995-2005 Jean-loup Gailly (jloup@gzip.org)
|
||||
Version 1.2.4
|
||||
Copyright (C) 1995-2010 Jean-loup Gailly (jloup@gzip.org)
|
||||
and Mark Adler (madler@alumni.caltech.edu).
|
||||
.LP
|
||||
This software is provided "as-is,"
|
||||
|
1137
lib/libz/zlib.h
1137
lib/libz/zlib.h
File diff suppressed because it is too large
Load Diff
@ -34,25 +34,25 @@ uLong ZEXPORT zlibCompileFlags()
|
||||
uLong flags;
|
||||
|
||||
flags = 0;
|
||||
switch (sizeof(uInt)) {
|
||||
switch ((int)(sizeof(uInt))) {
|
||||
case 2: break;
|
||||
case 4: flags += 1; break;
|
||||
case 8: flags += 2; break;
|
||||
default: flags += 3;
|
||||
}
|
||||
switch (sizeof(uLong)) {
|
||||
switch ((int)(sizeof(uLong))) {
|
||||
case 2: break;
|
||||
case 4: flags += 1 << 2; break;
|
||||
case 8: flags += 2 << 2; break;
|
||||
default: flags += 3 << 2;
|
||||
}
|
||||
switch (sizeof(voidpf)) {
|
||||
switch ((int)(sizeof(voidpf))) {
|
||||
case 2: break;
|
||||
case 4: flags += 1 << 4; break;
|
||||
case 8: flags += 2 << 4; break;
|
||||
default: flags += 3 << 4;
|
||||
}
|
||||
switch (sizeof(z_off_t)) {
|
||||
switch ((int)(sizeof(z_off_t))) {
|
||||
case 2: break;
|
||||
case 4: flags += 1 << 6; break;
|
||||
case 8: flags += 2 << 6; break;
|
||||
|
@ -1,5 +1,5 @@
|
||||
/* zutil.h -- internal interface and configuration of the compression library
|
||||
* Copyright (C) 1995-2005 Jean-loup Gailly.
|
||||
* Copyright (C) 1995-2010 Jean-loup Gailly.
|
||||
* For conditions of distribution and use, see copyright notice in zlib.h
|
||||
*/
|
||||
|
||||
@ -17,26 +17,24 @@
|
||||
#include "zlib.h"
|
||||
|
||||
#ifdef STDC
|
||||
# ifndef _WIN32_WCE
|
||||
# if !(defined(_WIN32_WCE) && defined(_MSC_VER))
|
||||
# include <stddef.h>
|
||||
# endif
|
||||
# include <string.h>
|
||||
# include <stdlib.h>
|
||||
#endif
|
||||
#ifdef NO_ERRNO_H
|
||||
# ifdef _WIN32_WCE
|
||||
/* The Microsoft C Run-Time Library for Windows CE doesn't have
|
||||
* errno. We define it as a global variable to simplify porting.
|
||||
* Its value is always 0 and should not be used. We rename it to
|
||||
* avoid conflict with other libraries that use the same workaround.
|
||||
*/
|
||||
# define errno z_errno
|
||||
# endif
|
||||
extern int errno;
|
||||
|
||||
#if defined(UNDER_CE) && defined(NO_ERRNO_H)
|
||||
# define zseterrno(ERR) SetLastError((DWORD)(ERR))
|
||||
# define zerrno() ((int)GetLastError())
|
||||
#else
|
||||
# ifndef _WIN32_WCE
|
||||
# ifdef NO_ERRNO_H
|
||||
extern int errno;
|
||||
# else
|
||||
# include <errno.h>
|
||||
# endif
|
||||
# define zseterrno(ERR) do { errno = (ERR); } while (0)
|
||||
# define zerrno() errno
|
||||
#endif
|
||||
|
||||
#ifndef local
|
||||
@ -89,7 +87,7 @@ extern const char * const z_errmsg[10]; /* indexed by 2-zlib_error */
|
||||
#if defined(MSDOS) || (defined(WINDOWS) && !defined(WIN32))
|
||||
# define OS_CODE 0x00
|
||||
# if defined(__TURBOC__) || defined(__BORLANDC__)
|
||||
# if(__STDC__ == 1) && (defined(__LARGE__) || defined(__COMPACT__))
|
||||
# if (__STDC__ == 1) && (defined(__LARGE__) || defined(__COMPACT__))
|
||||
/* Allow compilation with ANSI keywords only enabled */
|
||||
void _Cdecl farfree( void *block );
|
||||
void *_Cdecl farmalloc( unsigned long nbytes );
|
||||
@ -118,7 +116,7 @@ extern const char * const z_errmsg[10]; /* indexed by 2-zlib_error */
|
||||
#ifdef OS2
|
||||
# define OS_CODE 0x06
|
||||
# ifdef M_I86
|
||||
#include <malloc.h>
|
||||
# include <malloc.h>
|
||||
# endif
|
||||
#endif
|
||||
|
||||
@ -151,7 +149,7 @@ extern const char * const z_errmsg[10]; /* indexed by 2-zlib_error */
|
||||
# define fdopen(fd,mode) NULL /* No fdopen() */
|
||||
#endif
|
||||
|
||||
#if (defined(_MSC_VER) && (_MSC_VER > 600))
|
||||
#if (defined(_MSC_VER) && (_MSC_VER > 600)) && !defined __INTERIX
|
||||
# if defined(_WIN32_WCE)
|
||||
# define fdopen(fd,mode) NULL /* No fdopen() */
|
||||
# ifndef _PTRDIFF_T_DEFINED
|
||||
@ -161,6 +159,18 @@ extern const char * const z_errmsg[10]; /* indexed by 2-zlib_error */
|
||||
# else
|
||||
# define fdopen(fd,type) _fdopen(fd,type)
|
||||
# endif
|
||||
#endif
|
||||
|
||||
#if defined(__BORLANDC__)
|
||||
#pragma warn -8004
|
||||
#pragma warn -8008
|
||||
#pragma warn -8066
|
||||
#endif
|
||||
|
||||
#ifdef _LARGEFILE64_SOURCE
|
||||
# define z_off64_t off64_t
|
||||
#else
|
||||
# define z_off64_t z_off_t
|
||||
#endif
|
||||
|
||||
/* common defaults */
|
||||
@ -171,6 +181,12 @@ extern const char * const z_errmsg[10]; /* indexed by 2-zlib_error */
|
||||
|
||||
#ifndef F_OPEN
|
||||
# define F_OPEN(name, mode) fopen((name), (mode))
|
||||
#endif
|
||||
|
||||
#ifdef _LARGEFILE64_SOURCE
|
||||
# define F_OPEN64(name, mode) fopen64((name), (mode))
|
||||
#else
|
||||
# define F_OPEN64(name, mode) fopen((name), (mode))
|
||||
#endif
|
||||
|
||||
/* functions */
|
||||
@ -197,7 +213,9 @@ extern const char * const z_errmsg[10]; /* indexed by 2-zlib_error */
|
||||
# ifdef WIN32
|
||||
/* In Win32, vsnprintf is available as the "non-ANSI" _vsnprintf. */
|
||||
# if !defined(vsnprintf) && !defined(NO_vsnprintf)
|
||||
# define vsnprintf _vsnprintf
|
||||
# if !defined(_MSC_VER) || ( defined(_MSC_VER) && _MSC_VER < 1500 )
|
||||
# define vsnprintf _vsnprintf
|
||||
# endif
|
||||
# endif
|
||||
# endif
|
||||
# ifdef __SASC
|
||||
|
@ -58,7 +58,7 @@
|
||||
* in the range 5 to 9.
|
||||
*/
|
||||
#undef __FreeBSD_version
|
||||
#define __FreeBSD_version 900009 /* Master, propagated to newvers */
|
||||
#define __FreeBSD_version 900010 /* Master, propagated to newvers */
|
||||
|
||||
#ifndef LOCORE
|
||||
#include <sys/types.h>
|
||||
|
Loading…
Reference in New Issue
Block a user