/* * file - find type of a file or files - main program. * * Copyright (c) Ian F. Darwin, 1987. * Written by Ian F. Darwin. * * This software is not subject to any license of the American Telephone * and Telegraph Company or of the Regents of the University of California. * * Permission is granted to anyone to use this software for any purpose on * any computer system, and to alter it and redistribute it freely, subject * to the following restrictions: * * 1. The author is not responsible for the consequences of use of this * software, no matter how awful, even if they arise from flaws in it. * * 2. The origin of this software must not be misrepresented, either by * explicit claim or by omission. Since few users ever read sources, * credits must appear in the documentation. * * 3. Altered versions must be plainly marked as such, and must not be * misrepresented as being the original software. Since few users * ever read sources, credits must appear in the documentation. * * 4. This notice may not be removed or altered. */ #ifndef lint static char *moduleid = "@(#)$Id: file.c,v 1.1.1.1 1994/09/03 19:16:22 csgr Exp $"; #endif /* lint */ #include #include #include #include #include /* for MAXPATHLEN */ #include #include /* for open() */ #include #include /* for read() */ #include "file.h" #ifdef S_IFLNK # define USAGE "Usage: %s [-czL] [-f namefile] [-m magicfile] file...\n" #else # define USAGE "Usage: %s [-cz] [-f namefile] [-m magicfile] file...\n" #endif #ifndef MAGIC # define MAGIC "/etc/magic" #endif int /* Global command-line options */ debug = 0, /* debugging */ lflag = 0, /* follow Symlinks (BSD only) */ zflag = 0; /* follow (uncompress) compressed files */ int /* Misc globals */ nmagic = 0; /* number of valid magic[]s */ struct magic *magic; /* array of magic entries */ char *magicfile = MAGIC;/* where magic be found */ char *progname; /* used throughout */ int lineno; /* line number in the magic file */ static void unwrap __P((char *fn)); /* * main - parse arguments and handle options */ int main(argc, argv) int argc; char *argv[]; { int c; int check = 0, didsomefiles = 0, errflg = 0, ret = 0; if ((progname = strrchr(argv[0], '/')) != NULL) progname++; else progname = argv[0]; while ((c = getopt(argc, argv, "cdf:Lm:z")) != EOF) switch (c) { case 'c': ++check; break; case 'd': ++debug; break; case 'f': unwrap(optarg); ++didsomefiles; break; #ifdef S_IFLNK case 'L': ++lflag; break; #endif case 'm': magicfile = optarg; break; case 'z': zflag++; break; case '?': default: errflg++; break; } if (errflg) { (void) fprintf(stderr, USAGE, progname); exit(2); } ret = apprentice(magicfile, check); if (check) exit(ret); if (optind == argc) { if (!didsomefiles) { (void)fprintf(stderr, USAGE, progname); exit(2); } } else { int i, wid, nw; for (wid = 0, i = optind; i < argc; i++) { nw = strlen(argv[i]); if (nw > wid) wid = nw; } for (; optind < argc; optind++) process(argv[optind], wid); } return 0; } /* * unwrap -- read a file of filenames, do each one. */ static void unwrap(fn) char *fn; { char buf[MAXPATHLEN]; FILE *f; int wid = 0, cwid; if ((f = fopen(fn, "r")) == NULL) { error("Cannot open `%s' (%s).\n", fn, strerror(errno)); /*NOTREACHED*/ } while (fgets(buf, MAXPATHLEN, f) != NULL) { cwid = strlen(buf) - 1; if (cwid > wid) wid = cwid; } rewind(f); while (fgets(buf, MAXPATHLEN, f) != NULL) { buf[strlen(buf)-1] = '\0'; process(buf, wid); } (void) fclose(f); } /* * process - process input file */ void process(inname, wid) const char *inname; int wid; { int fd = 0; static const char stdname[] = "standard input"; unsigned char buf[HOWMANY+1]; /* one extra for terminating '\0' */ struct utimbuf utbuf; struct stat sb; int nbytes = 0; /* number of bytes read from a datafile */ if (strcmp("-", inname) == 0) { if (fstat(0, &sb)<0) { error("cannot fstat `%s' (%s).\n", stdname, strerror(errno)); /*NOTREACHED*/ } inname = stdname; } if (wid > 0) (void) printf("%s:%*s ", inname, (int) (wid - strlen(inname)), ""); if (inname != stdname) { /* * first try judging the file based on its filesystem status */ if (fsmagic(inname, &sb) != 0) { putchar('\n'); return; } if ((fd = open(inname, O_RDONLY)) < 0) { /* We can't open it, but we were able to stat it. */ if (sb.st_mode & 0002) ckfputs("writeable, ", stdout); if (sb.st_mode & 0111) ckfputs("executable, ", stdout); ckfprintf(stdout, "can't read `%s' (%s).\n", inname, strerror(errno)); return; } } /* * try looking at the first HOWMANY bytes */ if ((nbytes = read(fd, (char *)buf, HOWMANY)) == -1) { error("read failed (%s).\n", strerror(errno)); /*NOTREACHED*/ } if (nbytes == 0) ckfputs("empty", stdout); else { buf[nbytes++] = '\0'; /* null-terminate it */ tryit(buf, nbytes, zflag); } if (inname != stdname) { /* * Try to restore access, modification times if read it. */ utbuf.actime = sb.st_atime; utbuf.modtime = sb.st_mtime; (void) utime(inname, &utbuf); /* don't care if loses */ (void) close(fd); } (void) putchar('\n'); } void tryit(buf, nb, zflag) unsigned char *buf; int nb, zflag; { /* * Try compression stuff */ if (!zflag || zmagic(buf, nb) != 1) /* * try tests in /etc/magic (or surrogate magic file) */ if (softmagic(buf, nb) != 1) /* * try known keywords, check for ascii-ness too. */ if (ascmagic(buf, nb) != 1) /* * abandon hope, all ye who remain here */ ckfputs("data", stdout); }