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-rw-r--r--contrib/file/fsmagic.c363
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diff --git a/contrib/file/fsmagic.c b/contrib/file/fsmagic.c
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+/*
+ * Copyright (c) Ian F. Darwin 1986-1995.
+ * Software written by Ian F. Darwin and others;
+ * maintained 1995-present by Christos Zoulas and others.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice immediately at the beginning of the file, without modification,
+ * this list of conditions, and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+/*
+ * fsmagic - magic based on filesystem info - directory, special files, etc.
+ */
+
+#include "file.h"
+
+#ifndef lint
+FILE_RCSID("@(#)$File: fsmagic.c,v 1.59 2009/02/03 20:27:51 christos Exp $")
+#endif /* lint */
+
+#include "magic.h"
+#include <string.h>
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#include <stdlib.h>
+/* Since major is a function on SVR4, we cannot use `ifndef major'. */
+#ifdef MAJOR_IN_MKDEV
+# include <sys/mkdev.h>
+# define HAVE_MAJOR
+#endif
+#ifdef MAJOR_IN_SYSMACROS
+# include <sys/sysmacros.h>
+# define HAVE_MAJOR
+#endif
+#ifdef major /* Might be defined in sys/types.h. */
+# define HAVE_MAJOR
+#endif
+
+#ifndef HAVE_MAJOR
+# define major(dev) (((dev) >> 8) & 0xff)
+# define minor(dev) ((dev) & 0xff)
+#endif
+#undef HAVE_MAJOR
+
+private int
+bad_link(struct magic_set *ms, int err, char *buf)
+{
+ const char *errfmt;
+ int mime = ms->flags & MAGIC_MIME;
+ if ((mime & MAGIC_MIME_TYPE) &&
+ file_printf(ms, "application/x-symlink")
+ == -1)
+ return -1;
+ else if (!mime) {
+ if (err == ELOOP)
+ errfmt = "symbolic link in a loop";
+ else
+ errfmt = "broken symbolic link to `%s'";
+ if (ms->flags & MAGIC_ERROR) {
+ file_error(ms, err, errfmt, buf);
+ return -1;
+ }
+ if (file_printf(ms, errfmt, buf) == -1)
+ return -1;
+ }
+ return 1;
+}
+
+private int
+handle_mime(struct magic_set *ms, int mime, const char *str)
+{
+ if ((mime & MAGIC_MIME_TYPE)) {
+ if (file_printf(ms, "application/%s", str) == -1)
+ return -1;
+ if ((mime & MAGIC_MIME_ENCODING) && file_printf(ms,
+ "; charset=") == -1)
+ return -1;
+ }
+ if ((mime & MAGIC_MIME_ENCODING) && file_printf(ms, "binary") == -1)
+ return -1;
+ return 0;
+}
+
+protected int
+file_fsmagic(struct magic_set *ms, const char *fn, struct stat *sb)
+{
+ int ret = 0;
+ int mime = ms->flags & MAGIC_MIME;
+#ifdef S_IFLNK
+ char buf[BUFSIZ+4];
+ int nch;
+ struct stat tstatbuf;
+#endif
+
+ if (ms->flags & MAGIC_APPLE)
+ return 0;
+ if (fn == NULL)
+ return 0;
+
+ /*
+ * Fstat is cheaper but fails for files you don't have read perms on.
+ * On 4.2BSD and similar systems, use lstat() to identify symlinks.
+ */
+#ifdef S_IFLNK
+ if ((ms->flags & MAGIC_SYMLINK) == 0)
+ ret = lstat(fn, sb);
+ else
+#endif
+ ret = stat(fn, sb); /* don't merge into if; see "ret =" above */
+
+ if (ret) {
+ if (ms->flags & MAGIC_ERROR) {
+ file_error(ms, errno, "cannot stat `%s'", fn);
+ return -1;
+ }
+ if (file_printf(ms, "cannot open `%s' (%s)",
+ fn, strerror(errno)) == -1)
+ return -1;
+ return 1;
+ }
+
+ if (!mime) {
+#ifdef S_ISUID
+ if (sb->st_mode & S_ISUID)
+ if (file_printf(ms, "setuid ") == -1)
+ return -1;
+#endif
+#ifdef S_ISGID
+ if (sb->st_mode & S_ISGID)
+ if (file_printf(ms, "setgid ") == -1)
+ return -1;
+#endif
+#ifdef S_ISVTX
+ if (sb->st_mode & S_ISVTX)
+ if (file_printf(ms, "sticky ") == -1)
+ return -1;
+#endif
+ }
+
+ switch (sb->st_mode & S_IFMT) {
+ case S_IFDIR:
+ if (mime) {
+ if (handle_mime(ms, mime, "x-directory") == -1)
+ return -1;
+ } else if (file_printf(ms, "directory") == -1)
+ return -1;
+ return 1;
+#ifdef S_IFCHR
+ case S_IFCHR:
+ /*
+ * If -s has been specified, treat character special files
+ * like ordinary files. Otherwise, just report that they
+ * are block special files and go on to the next file.
+ */
+ if ((ms->flags & MAGIC_DEVICES) != 0)
+ break;
+ if (mime) {
+ if (handle_mime(ms, mime, "x-character-device") == -1)
+ return -1;
+ } else {
+#ifdef HAVE_STAT_ST_RDEV
+# ifdef dv_unit
+ if (file_printf(ms, "character special (%d/%d/%d)",
+ major(sb->st_rdev), dv_unit(sb->st_rdev),
+ dv_subunit(sb->st_rdev)) == -1)
+ return -1;
+# else
+ if (file_printf(ms, "character special (%ld/%ld)",
+ (long)major(sb->st_rdev), (long)minor(sb->st_rdev))
+ == -1)
+ return -1;
+# endif
+#else
+ if (file_printf(ms, "character special") == -1)
+ return -1;
+#endif
+ }
+ return 1;
+#endif
+#ifdef S_IFBLK
+ case S_IFBLK:
+ /*
+ * If -s has been specified, treat block special files
+ * like ordinary files. Otherwise, just report that they
+ * are block special files and go on to the next file.
+ */
+ if ((ms->flags & MAGIC_DEVICES) != 0)
+ break;
+ if (mime) {
+ if (handle_mime(ms, mime, "x-block-device") == -1)
+ return -1;
+ } else {
+#ifdef HAVE_STAT_ST_RDEV
+# ifdef dv_unit
+ if (file_printf(ms, "block special (%d/%d/%d)",
+ major(sb->st_rdev), dv_unit(sb->st_rdev),
+ dv_subunit(sb->st_rdev)) == -1)
+ return -1;
+# else
+ if (file_printf(ms, "block special (%ld/%ld)",
+ (long)major(sb->st_rdev), (long)minor(sb->st_rdev)) == -1)
+ return -1;
+# endif
+#else
+ if (file_printf(ms, "block special") == -1)
+ return -1;
+#endif
+ }
+ return 1;
+#endif
+ /* TODO add code to handle V7 MUX and Blit MUX files */
+#ifdef S_IFIFO
+ case S_IFIFO:
+ if((ms->flags & MAGIC_DEVICES) != 0)
+ break;
+ if (mime) {
+ if (handle_mime(ms, mime, "x-fifo") == -1)
+ return -1;
+ } else if (file_printf(ms, "fifo (named pipe)") == -1)
+ return -1;
+ return 1;
+#endif
+#ifdef S_IFDOOR
+ case S_IFDOOR:
+ if (mime) {
+ if (handle_mime(ms, mime, "x-door") == -1)
+ return -1;
+ } else if (file_printf(ms, "door") == -1)
+ return -1;
+ return 1;
+#endif
+#ifdef S_IFLNK
+ case S_IFLNK:
+ if ((nch = readlink(fn, buf, BUFSIZ-1)) <= 0) {
+ if (ms->flags & MAGIC_ERROR) {
+ file_error(ms, errno, "unreadable symlink `%s'",
+ fn);
+ return -1;
+ }
+ if (mime) {
+ if (handle_mime(ms, mime, "x-symlink") == -1)
+ return -1;
+ } else if (file_printf(ms,
+ "unreadable symlink `%s' (%s)", fn,
+ strerror(errno)) == -1)
+ return -1;
+ return 1;
+ }
+ buf[nch] = '\0'; /* readlink(2) does not do this */
+
+ /* If broken symlink, say so and quit early. */
+ if (*buf == '/') {
+ if (stat(buf, &tstatbuf) < 0)
+ return bad_link(ms, errno, buf);
+ } else {
+ char *tmp;
+ char buf2[BUFSIZ+BUFSIZ+4];
+
+ if ((tmp = strrchr(fn, '/')) == NULL) {
+ tmp = buf; /* in current directory anyway */
+ } else {
+ if (tmp - fn + 1 > BUFSIZ) {
+ if (ms->flags & MAGIC_ERROR) {
+ file_error(ms, 0,
+ "path too long: `%s'", buf);
+ return -1;
+ }
+ if (mime) {
+ if (handle_mime(ms, mime,
+ "x-path-too-long") == -1)
+ return -1;
+ } else if (file_printf(ms,
+ "path too long: `%s'", fn) == -1)
+ return -1;
+ return 1;
+ }
+ /* take dir part */
+ (void)strlcpy(buf2, fn, sizeof buf2);
+ buf2[tmp - fn + 1] = '\0';
+ /* plus (rel) link */
+ (void)strlcat(buf2, buf, sizeof buf2);
+ tmp = buf2;
+ }
+ if (stat(tmp, &tstatbuf) < 0)
+ return bad_link(ms, errno, buf);
+ }
+
+ /* Otherwise, handle it. */
+ if ((ms->flags & MAGIC_SYMLINK) != 0) {
+ const char *p;
+ ms->flags &= MAGIC_SYMLINK;
+ p = magic_file(ms, buf);
+ ms->flags |= MAGIC_SYMLINK;
+ return p != NULL ? 1 : -1;
+ } else { /* just print what it points to */
+ if (mime) {
+ if (handle_mime(ms, mime, "x-symlink") == -1)
+ return -1;
+ } else if (file_printf(ms, "symbolic link to `%s'",
+ buf) == -1)
+ return -1;
+ }
+ return 1;
+#endif
+#ifdef S_IFSOCK
+#ifndef __COHERENT__
+ case S_IFSOCK:
+ if (mime) {
+ if (handle_mime(ms, mime, "x-socket") == -1)
+ return -1;
+ } else if (file_printf(ms, "socket") == -1)
+ return -1;
+ return 1;
+#endif
+#endif
+ case S_IFREG:
+ break;
+ default:
+ file_error(ms, 0, "invalid mode 0%o", sb->st_mode);
+ return -1;
+ /*NOTREACHED*/
+ }
+
+ /*
+ * regular file, check next possibility
+ *
+ * If stat() tells us the file has zero length, report here that
+ * the file is empty, so we can skip all the work of opening and
+ * reading the file.
+ * But if the -s option has been given, we skip this optimization,
+ * since on some systems, stat() reports zero size for raw disk
+ * partitions. (If the block special device really has zero length,
+ * the fact that it is empty will be detected and reported correctly
+ * when we read the file.)
+ */
+ if ((ms->flags & MAGIC_DEVICES) == 0 && sb->st_size == 0) {
+ if (mime) {
+ if (handle_mime(ms, mime, "x-empty") == -1)
+ return -1;
+ } else if (file_printf(ms, "empty") == -1)
+ return -1;
+ return 1;
+ }
+ return 0;
+}
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