2 * Copyright (c) Christos Zoulas 2003.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice immediately at the beginning of the file, without modification,
10 * this list of conditions, and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
19 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 #include <sys/types.h>
36 #include <sys/param.h> /* for MAXPATHLEN */
42 #include <limits.h> /* for PIPE_BUF */
45 #if defined(HAVE_UTIMES)
46 # include <sys/time.h>
47 #elif defined(HAVE_UTIME)
48 # if defined(HAVE_SYS_UTIME_H)
49 # include <sys/utime.h>
50 # elif defined(HAVE_UTIME_H)
56 #include <unistd.h> /* for read() */
63 #include <netinet/in.h> /* for byte swapping */
65 #include "patchlevel.h"
68 FILE_RCSID("@(#)$File: magic.c,v 1.54 2008/07/25 23:30:32 rrt Exp $")
72 /* Get the PIPE_BUF from pathconf */
74 #define PIPE_BUF pathconf(".", _PC_PIPE_BUF)
81 private char *apptypeName = NULL;
82 protected int file_os2_apptype(struct magic_set *ms, const char *fn,
83 const void *buf, size_t nb);
86 private void free_mlist(struct mlist *);
87 private void close_and_restore(const struct magic_set *, const char *, int,
89 private int unreadable_info(struct magic_set *, mode_t, const char *);
91 private const char *file_or_fd(struct magic_set *, const char *, int);
95 #define STDIN_FILENO 0
98 public struct magic_set *
101 struct magic_set *ms;
104 if ((ms = CAST(magic_set *, calloc((size_t)1,
105 sizeof(struct magic_set)))) == NULL)
108 if (magic_setflags(ms, flags) == -1) {
113 ms->o.buf = ms->o.pbuf = NULL;
114 len = (ms->c.len = 10) * sizeof(*ms->c.li);
116 if ((ms->c.li = CAST(struct level_info *, malloc(len))) == NULL)
122 ms->file = "unknown";
131 free_mlist(struct mlist *mlist)
138 for (ml = mlist->next; ml != mlist;) {
139 struct mlist *next = ml->next;
140 struct magic *mg = ml->magic;
141 file_delmagic(mg, ml->mapped, ml->nmagic);
149 unreadable_info(struct magic_set *ms, mode_t md, const char *file)
151 /* We cannot open it, but we were able to stat it. */
152 if (access(file, W_OK) == 0)
153 if (file_printf(ms, "writable, ") == -1)
155 if (access(file, X_OK) == 0)
156 if (file_printf(ms, "executable, ") == -1)
159 if (file_printf(ms, "regular file, ") == -1)
161 if (file_printf(ms, "no read permission") == -1)
167 magic_close(struct magic_set *ms)
169 free_mlist(ms->mlist);
180 magic_load(struct magic_set *ms, const char *magicfile)
182 struct mlist *ml = file_apprentice(ms, magicfile, FILE_LOAD);
184 free_mlist(ms->mlist);
192 magic_compile(struct magic_set *ms, const char *magicfile)
194 struct mlist *ml = file_apprentice(ms, magicfile, FILE_COMPILE);
200 magic_check(struct magic_set *ms, const char *magicfile)
202 struct mlist *ml = file_apprentice(ms, magicfile, FILE_CHECK);
208 close_and_restore(const struct magic_set *ms, const char *name, int fd,
209 const struct stat *sb)
211 if (fd == STDIN_FILENO)
215 if ((ms->flags & MAGIC_PRESERVE_ATIME) != 0) {
217 * Try to restore access, modification times if read it.
218 * This is really *bad* because it will modify the status
219 * time of the file... And of course this will affect
223 struct timeval utsbuf[2];
224 (void)memset(utsbuf, 0, sizeof(utsbuf));
225 utsbuf[0].tv_sec = sb->st_atime;
226 utsbuf[1].tv_sec = sb->st_mtime;
228 (void) utimes(name, utsbuf); /* don't care if loses */
229 #elif defined(HAVE_UTIME_H) || defined(HAVE_SYS_UTIME_H)
230 struct utimbuf utbuf;
232 (void)memset(utbuf, 0, sizeof(utbuf));
233 utbuf.actime = sb->st_atime;
234 utbuf.modtime = sb->st_mtime;
235 (void) utime(name, &utbuf); /* don't care if loses */
243 * find type of descriptor
246 magic_descriptor(struct magic_set *ms, int fd)
248 return file_or_fd(ms, NULL, fd);
252 * find type of named file
255 magic_file(struct magic_set *ms, const char *inname)
257 return file_or_fd(ms, inname, STDIN_FILENO);
261 file_or_fd(struct magic_set *ms, const char *inname, int fd)
266 ssize_t nbytes = 0; /* number of bytes read from a datafile */
270 * one extra for terminating '\0', and
271 * some overlapping space for matches near EOF
273 #define SLOP (1 + sizeof(union VALUETYPE))
274 if ((buf = CAST(unsigned char *, malloc(HOWMANY + SLOP))) == NULL)
277 if (file_reset(ms) == -1)
280 switch (file_fsmagic(ms, inname, &sb)) {
283 case 0: /* nothing found */
285 default: /* matched it and printed type */
290 if (inname == NULL) {
291 if (fstat(fd, &sb) == 0 && S_ISFIFO(sb.st_mode))
294 int flags = O_RDONLY|O_BINARY;
296 if (stat(inname, &sb) == 0 && S_ISFIFO(sb.st_mode)) {
302 if ((fd = open(inname, flags)) < 0) {
304 /* FIXME: Do this with EXEEXT from autotools */
305 char *tmp = alloca(strlen(inname) + 5);
306 (void)strcat(strcpy(tmp, inname), ".exe");
307 if ((fd = open(tmp, flags)) < 0) {
309 if (unreadable_info(ms, sb.st_mode,
324 if ((flags = fcntl(fd, F_GETFL)) != -1) {
325 flags &= ~O_NONBLOCK;
326 (void)fcntl(fd, F_SETFL, flags);
332 * try looking at the first HOWMANY bytes
337 while ((r = sread(fd, (void *)&buf[nbytes],
338 (size_t)(HOWMANY - nbytes), 1)) > 0) {
340 if (r < PIPE_BUF) break;
344 /* We can not read it, but we were able to stat it. */
345 if (unreadable_info(ms, sb.st_mode, inname) == -1)
352 if ((nbytes = read(fd, (char *)buf, HOWMANY)) == -1) {
353 file_error(ms, errno, "cannot read `%s'", inname);
358 (void)memset(buf + nbytes, 0, SLOP); /* NUL terminate */
359 if (file_buffer(ms, fd, inname, buf, (size_t)nbytes) == -1)
364 close_and_restore(ms, inname, fd, &sb);
365 return rv == 0 ? file_getbuffer(ms) : NULL;
370 magic_buffer(struct magic_set *ms, const void *buf, size_t nb)
372 if (file_reset(ms) == -1)
375 * The main work is done here!
376 * We have the file name and/or the data buffer to be identified.
378 if (file_buffer(ms, -1, NULL, buf, nb) == -1) {
381 return file_getbuffer(ms);
386 magic_error(struct magic_set *ms)
388 return ms->haderr ? ms->o.buf : NULL;
392 magic_errno(struct magic_set *ms)
394 return ms->haderr ? ms->error : 0;
398 magic_setflags(struct magic_set *ms, int flags)
400 #if !defined(HAVE_UTIME) && !defined(HAVE_UTIMES)
401 if (flags & MAGIC_PRESERVE_ATIME)