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98 lines
3.4 KiB
C
98 lines
3.4 KiB
C
/* Work around a bug of lstat on some systems
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Copyright (C) 1997-2006, 2008-2017 Free Software Foundation, Inc.
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This program is free software: you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program. If not, see <http://www.gnu.org/licenses/>. */
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/* written by Jim Meyering */
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/* If the user's config.h happens to include <sys/stat.h>, let it include only
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the system's <sys/stat.h> here, so that orig_lstat doesn't recurse to
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rpl_lstat. */
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#define __need_system_sys_stat_h
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#include <config.h>
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#if !HAVE_LSTAT
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/* On systems that lack symlinks, our replacement <sys/stat.h> already
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defined lstat as stat, so there is nothing further to do other than
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avoid an empty file. */
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typedef int dummy;
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#else /* HAVE_LSTAT */
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/* Get the original definition of lstat. It might be defined as a macro. */
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# include <sys/types.h>
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# include <sys/stat.h>
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# undef __need_system_sys_stat_h
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static int
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orig_lstat (const char *filename, struct stat *buf)
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{
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return lstat (filename, buf);
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}
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/* Specification. */
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/* Write "sys/stat.h" here, not <sys/stat.h>, otherwise OSF/1 5.1 DTK cc
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eliminates this include because of the preliminary #include <sys/stat.h>
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above. */
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# include "sys/stat.h"
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# include <string.h>
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# include <errno.h>
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/* lstat works differently on Linux and Solaris systems. POSIX (see
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"pathname resolution" in the glossary) requires that programs like
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'ls' take into consideration the fact that FILE has a trailing slash
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when FILE is a symbolic link. On Linux and Solaris 10 systems, the
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lstat function already has the desired semantics (in treating
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'lstat ("symlink/", sbuf)' just like 'lstat ("symlink/.", sbuf)',
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but on Solaris 9 and earlier it does not.
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If FILE has a trailing slash and specifies a symbolic link,
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then use stat() to get more info on the referent of FILE.
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If the referent is a non-directory, then set errno to ENOTDIR
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and return -1. Otherwise, return stat's result. */
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int
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rpl_lstat (const char *file, struct stat *sbuf)
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{
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size_t len;
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int lstat_result = orig_lstat (file, sbuf);
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if (lstat_result != 0)
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return lstat_result;
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/* This replacement file can blindly check against '/' rather than
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using the ISSLASH macro, because all platforms with '\\' either
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lack symlinks (mingw) or have working lstat (cygwin) and thus do
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not compile this file. 0 len should have already been filtered
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out above, with a failure return of ENOENT. */
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len = strlen (file);
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if (file[len - 1] != '/' || S_ISDIR (sbuf->st_mode))
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return 0;
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/* At this point, a trailing slash is only permitted on
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symlink-to-dir; but it should have found information on the
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directory, not the symlink. Call stat() to get info about the
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link's referent. Our replacement stat guarantees valid results,
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even if the symlink is not pointing to a directory. */
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if (!S_ISLNK (sbuf->st_mode))
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{
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errno = ENOTDIR;
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return -1;
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}
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return stat (file, sbuf);
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}
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#endif /* HAVE_LSTAT */
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