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- /*
- * 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 1.39 1998/02/15 23:18:53 christos Exp $";
- #endif /* lint */
- #include <stdio.h>
- #include <stdlib.h>
- #include <string.h>
- #include <sys/types.h>
- #include <sys/param.h> /* for MAXPATHLEN */
- #include <sys/stat.h>
- #include <fcntl.h> /* for open() */
- #if (__COHERENT__ >= 0x420)
- # include <sys/utime.h>
- #else
- # ifdef USE_UTIMES
- # include <sys/time.h>
- # else
- # include <utime.h>
- # endif
- #endif
- #include <unistd.h> /* for read() */
- #include <netinet/in.h> /* for byte swapping */
- #include "patchlevel.h"
- #include "file.h"
- #ifdef S_IFLNK
- # define USAGE "Usage: %s [-vbczL] [-f namefile] [-m magicfiles] file...\n"
- #else
- # define USAGE "Usage: %s [-vbcz] [-f namefile] [-m magicfiles] file...\n"
- #endif
- #ifndef MAGIC
- # define MAGIC "/etc/magic"
- #endif
- int /* Global command-line options */
- debug = 0, /* debugging */
- lflag = 0, /* follow Symlinks (BSD only) */
- bflag = 0, /* brief output format */
- 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; /* where magic be found */
- char *progname; /* used throughout */
- int lineno; /* line number in the magic file */
- static void unwrap __P((char *fn));
- #if 0
- static int byteconv4 __P((int, int, int));
- static short byteconv2 __P((int, int, int));
- #endif
- /*
- * 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, app = 0;
- if ((progname = strrchr(argv[0], '/')) != NULL)
- progname++;
- else
- progname = argv[0];
- if (!(magicfile = getenv("MAGIC")))
- magicfile = MAGIC;
- while ((c = getopt(argc, argv, "vbcdf:Lm:z")) != EOF)
- switch (c) {
- case 'v':
- (void) fprintf(stdout, "%s-%d.%d\n", progname,
- FILE_VERSION_MAJOR, patchlevel);
- return 1;
- case 'b':
- ++bflag;
- break;
- case 'c':
- ++check;
- break;
- case 'd':
- ++debug;
- break;
- case 'f':
- if (!app) {
- ret = apprentice(magicfile, check);
- if (check)
- exit(ret);
- app = 1;
- }
- 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);
- }
- if (!app) {
- ret = apprentice(magicfile, check);
- if (check)
- exit(ret);
- app = 1;
- }
- 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 (strcmp("-", fn) == 0) {
- f = stdin;
- wid = 1;
- } else {
- 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);
- }
- #if 0
- /*
- * byteconv4
- * Input:
- * from 4 byte quantity to convert
- * same whether to perform byte swapping
- * big_endian whether we are a big endian host
- */
- static int
- byteconv4(from, same, big_endian)
- int from;
- int same;
- int big_endian;
- {
- if (same)
- return from;
- else if (big_endian) /* lsb -> msb conversion on msb */
- {
- union {
- int i;
- char c[4];
- } retval, tmpval;
- tmpval.i = from;
- retval.c[0] = tmpval.c[3];
- retval.c[1] = tmpval.c[2];
- retval.c[2] = tmpval.c[1];
- retval.c[3] = tmpval.c[0];
- return retval.i;
- }
- else
- return ntohl(from); /* msb -> lsb conversion on lsb */
- }
- /*
- * byteconv2
- * Same as byteconv4, but for shorts
- */
- static short
- byteconv2(from, same, big_endian)
- int from;
- int same;
- int big_endian;
- {
- if (same)
- return from;
- else if (big_endian) /* lsb -> msb conversion on msb */
- {
- union {
- short s;
- char c[2];
- } retval, tmpval;
- tmpval.s = (short) from;
- retval.c[0] = tmpval.c[1];
- retval.c[1] = tmpval.c[0];
- return retval.s;
- }
- else
- return ntohs(from); /* msb -> lsb conversion on lsb */
- }
- #endif
- /*
- * 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 stat sb;
- int nbytes = 0; /* number of bytes read from a datafile */
- char match = '\0';
- if (strcmp("-", inname) == 0) {
- if (fstat(0, &sb)<0) {
- error("cannot fstat `%s' (%s).\n", stdname,
- strerror(errno));
- /*NOTREACHED*/
- }
- inname = stdname;
- }
- if (wid > 0 && !bflag)
- (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 */
- match = tryit(buf, nbytes, zflag);
- }
- #ifdef BUILTIN_ELF
- if (match == 's' && nbytes > 5)
- tryelf(fd, buf, nbytes);
- #endif
- if (inname != stdname) {
- #ifdef RESTORE_TIME
- /*
- * Try to restore access, modification times if read it.
- */
- # ifdef USE_UTIMES
- struct timeval utsbuf[2];
- utsbuf[0].tv_sec = sb.st_atime;
- utsbuf[1].tv_sec = sb.st_mtime;
- (void) utimes(inname, utsbuf); /* don't care if loses */
- # else
- struct utimbuf utbuf;
- utbuf.actime = sb.st_atime;
- utbuf.modtime = sb.st_mtime;
- (void) utime(inname, &utbuf); /* don't care if loses */
- # endif
- #endif
- (void) close(fd);
- }
- (void) putchar('\n');
- }
- int
- tryit(buf, nb, zflag)
- unsigned char *buf;
- int nb, zflag;
- {
- /* try compression stuff */
- if (zflag && zmagic(buf, nb))
- return 'z';
- /* try tests in /etc/magic (or surrogate magic file) */
- if (softmagic(buf, nb))
- return 's';
- /* try known keywords, check whether it is ASCII */
- if (ascmagic(buf, nb))
- return 'a';
- /* see if it's international language text */
- if (internatmagic(buf, nb))
- return 'i';
- /* abandon hope, all ye who remain here */
- ckfputs("data", stdout);
- return '\0';
- }
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