/*
* fsmagic - magic based on filesystem info - directory, special files, etc.
*
* 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.
*/
#include "file.h"
#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <stdlib.h>
/* Since major is a function on SVR4, we can't 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
#ifndef lint
FILE_RCSID("@(#)$Id: fsmagic.c,v 1.33 2000/08/05 17:36:48 christos Exp $")
#endif /* lint */
int
fsmagic(fn, sb)
const char *fn;
struct stat *sb;
{
int ret = 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 (!lflag)
ret = lstat(fn, sb);
else
#endif
ret = stat(fn, sb); /* don't merge into if; see "ret =" above */
if (ret) {
ckfprintf(stdout,
/* Yes, I do mean stdout. */
/* No \n, caller will provide. */
"can't stat `%s' (%s).", fn, strerror(errno));
return 1;
}
if (iflag) {
if ((sb->st_mode & S_IFMT) != S_IFREG) {
ckfputs("application/x-not-regular-file", stdout);
return 1;
}
}
else {
#ifdef S_ISUID
if (sb->st_mode & S_ISUID) ckfputs("setuid ", stdout);
#endif
#ifdef S_ISGID
if (sb->st_mode & S_ISGID) ckfputs("setgid ", stdout);
#endif
#ifdef S_ISVTX
if (sb->st_mode & S_ISVTX) ckfputs("sticky ", stdout);
#endif
}
switch (sb->st_mode & S_IFMT) {
case S_IFDIR:
ckfputs("directory", stdout);
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 (sflag)
break;
#ifdef HAVE_ST_RDEV
# ifdef dv_unit
(void) printf("character special (%d/%d/%d)",
major(sb->st_rdev),
dv_unit(sb->st_rdev),
dv_subunit(sb->st_rdev));
# else
(void) printf("character special (%ld/%ld)",
(long) major(sb->st_rdev), (long) minor(sb->st_rdev));
# endif
#else
(void) printf("character special");
#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 (sflag)
break;
#ifdef HAVE_ST_RDEV
# ifdef dv_unit
(void) printf("block special (%d/%d/%d)",
major(sb->st_rdev),
dv_unit(sb->st_rdev),
dv_subunit(sb->st_rdev));
# else
(void) printf("block special (%ld/%ld)",
(long) major(sb->st_rdev), (long) minor(sb->st_rdev));
# endif
#else
(void) printf("block special");
#endif
return 1;
#endif
/* TODO add code to handle V7 MUX and Blit MUX files */
#ifdef S_IFIFO
case S_IFIFO:
ckfputs("fifo (named pipe)", stdout);
return 1;
#endif
#ifdef S_IFDOOR
case S_IFDOOR:
ckfputs("door", stdout);
return 1;
#endif
#ifdef S_IFLNK
case S_IFLNK:
{
char buf[BUFSIZ+4];
int nch;
struct stat tstatbuf;
if ((nch = readlink(fn, buf, BUFSIZ-1)) <= 0) {
ckfprintf(stdout, "unreadable symlink (%s).",
strerror(errno));
return 1;
}
buf[nch] = '\0'; /* readlink(2) forgets this */
/* If broken symlink, say so and quit early. */
if (*buf == '/') {
if (stat(buf, &tstatbuf) < 0) {
ckfprintf(stdout,
"broken symbolic link to %s", buf);
return 1;
}
}
else {
char *tmp;
char buf2[BUFSIZ+BUFSIZ+4];
if ((tmp = strrchr(fn, '/')) == NULL) {
tmp = buf; /* in current directory anyway */
}
else {
strcpy (buf2, fn); /* take directory part */
buf2[tmp-fn+1] = '\0';
strcat (buf2, buf); /* plus (relative) symlink */
tmp = buf2;
}
if (stat(tmp, &tstatbuf) < 0) {
ckfprintf(stdout,
"broken symbolic link to %s", buf);
return 1;
}
}
/* Otherwise, handle it. */
if (lflag) {
process(buf, strlen(buf));
return 1;
} else { /* just print what it points to */
ckfputs("symbolic link to ", stdout);
ckfputs(buf, stdout);
}
}
return 1;
#endif
#ifdef S_IFSOCK
#ifndef __COHERENT__
case S_IFSOCK:
ckfputs("socket", stdout);
return 1;
#endif
#endif
case S_IFREG:
break;
default:
error("invalid mode 0%o.\n", sb->st_mode);
/*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 (!sflag && sb->st_size == 0) {
ckfputs(iflag ? "application/x-empty" : "empty", stdout);
return 1;
}
return 0;
}
