file/fsmagic.c

   1 /*
   2  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Portions Copyright (c) 1999 Apple Computer, Inc.  All Rights
   7  * Reserved.  This file contains Original Code and/or Modifications of
   8  * Original Code as defined in and that are subject to the Apple Public
   9  * Source License Version 1.1 (the "License").  You may not use this file
  10  * except in compliance with the License.  Please obtain a copy of the
  11  * License at http://www.apple.com/publicsource and read it before using
  12  * this file.
  13  *
  14  * The Original Code and all software distributed under the License are
  15  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  16  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  17  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE OR NON- INFRINGEMENT.  Please see the
  19  * License for the specific language governing rights and limitations
  20  * under the License.
  21  *
  22  * @APPLE_LICENSE_HEADER_END@
  23  */
  24 /*      $OpenBSD: fsmagic.c,v 1.3 1997/02/09 23:58:24 millert Exp $     */
  25
  26 /*
  27  * fsmagic - magic based on filesystem info - directory, special files, etc.
  28  *
  29  * Copyright (c) Ian F. Darwin, 1987.
  30  * Written by Ian F. Darwin.
  31  *
  32  * This software is not subject to any license of the American Telephone
  33  * and Telegraph Company or of the Regents of the University of California.
  34  *
  35  * Permission is granted to anyone to use this software for any purpose on
  36  * any computer system, and to alter it and redistribute it freely, subject
  37  * to the following restrictions:
  38  *
  39  * 1. The author is not responsible for the consequences of use of this
  40  *    software, no matter how awful, even if they arise from flaws in it.
  41  *
  42  * 2. The origin of this software must not be misrepresented, either by
  43  *    explicit claim or by omission.  Since few users ever read sources,
  44  *    credits must appear in the documentation.
  45  *
  46  * 3. Altered versions must be plainly marked as such, and must not be
  47  *    misrepresented as being the original software.  Since few users
  48  *    ever read sources, credits must appear in the documentation.
  49  *
  50  * 4. This notice may not be removed or altered.
  51  */
  52
  53 #include <stdio.h>
  54 #include <string.h>
  55 #include <sys/types.h>
  56 #include <sys/stat.h>
  57 #include <unistd.h>
  58 #include <stdlib.h>
  59 #ifndef major
  60 # if defined(__SVR4) || defined(_SVR4_SOURCE)
  61 #  include <sys/mkdev.h>
  62 # endif
  63 #endif
  64 #ifndef major                   /* if `major' not defined in types.h, */
  65 #include <sys/sysmacros.h>      /* try this one. */
  66 #endif
  67 #ifndef major   /* still not defined? give up, manual intervention needed */
  68                 /* If cc tries to compile this, read and act on it. */
  69                 /* On most systems cpp will discard it automatically */
  70                 Congratulations, you have found a portability bug.
  71                 Please grep /usr/include/sys and edit the above #include
  72                 to point at the file that defines the "major" macro.
  73 #endif  /*major*/
  74
  75 #include "file.h"
  76
  77 #ifndef lint
  78 #if 0
  79 static char *moduleid = "$OpenBSD: fsmagic.c,v 1.3 1997/02/09 23:58:24 millert Exp $";
  80 #endif
  81 #endif  /* lint */
  82
  83 int
  84 fsmagic(fn, sb)
  85 const char *fn;
  86 struct stat *sb;
  87 {
  88         int ret = 0;
  89
  90         /*
  91          * Fstat is cheaper but fails for files you don't have read perms on.
  92          * On 4.2BSD and similar systems, use lstat() to identify symlinks.
  93          */
  94 #ifdef  S_IFLNK
  95         if (!lflag)
  96                 ret = lstat(fn, sb);
  97         else
  98 #endif
  99         ret = stat(fn, sb);     /* don't merge into if; see "ret =" above */
 100
 101         if (ret) {
 102                 ckfprintf(stdout,
 103                         /* Yes, I do mean stdout. */
 104                         /* No \n, caller will provide. */
 105                         "can't stat `%s' (%s).", fn, strerror(errno));
 106                 return 1;
 107         }
 108
 109         if (sb->st_mode & S_ISUID) ckfputs("setuid ", stdout);
 110         if (sb->st_mode & S_ISGID) ckfputs("setgid ", stdout);
 111         if (sb->st_mode & S_ISVTX) ckfputs("sticky ", stdout);
 112
 113         switch (sb->st_mode & S_IFMT) {
 114         case S_IFDIR:
 115                 ckfputs("directory", stdout);
 116                 return 1;
 117         case S_IFCHR:
 118                 (void) printf("character special (%ld/%ld)",
 119                         (long) major(sb->st_rdev), (long) minor(sb->st_rdev));
 120                 return 1;
 121         case S_IFBLK:
 122                 (void) printf("block special (%ld/%ld)",
 123                         (long) major(sb->st_rdev), (long) minor(sb->st_rdev));
 124                 return 1;
 125         /* TODO add code to handle V7 MUX and Blit MUX files */
 126 #ifdef  S_IFIFO
 127         case S_IFIFO:
 128                 ckfputs("fifo (named pipe)", stdout);
 129                 return 1;
 130 #endif
 131 #ifdef  S_IFLNK
 132         case S_IFLNK:
 133                 {
 134                         char buf[BUFSIZ+4];
 135                         register int nch;
 136                         struct stat tstatbuf;
 137
 138                         if ((nch = readlink(fn, buf, BUFSIZ-1)) <= 0) {
 139                                 ckfprintf(stdout, "unreadable symlink (%s).",
 140                                       strerror(errno));
 141                                 return 1;
 142                         }
 143                         buf[nch] = '\0';        /* readlink(2) forgets this */
 144
 145                         /* If broken symlink, say so and quit early. */
 146                         if (*buf == '/') {
 147                             if (stat(buf, &tstatbuf) < 0) {
 148                                 ckfprintf(stdout,
 149                                         "broken symbolic link to %s", buf);
 150                                 return 1;
 151                             }
 152                         }
 153                         else {
 154                             char *tmp;
 155                             char buf2[BUFSIZ+BUFSIZ+4];
 156
 157                             if ((tmp = strrchr(fn,  '/')) == NULL) {
 158                                 tmp = buf; /* in current directory anyway */
 159                             }
 160                             else {
 161                                 strcpy (buf2, fn);  /* take directory part */
 162                                 buf2[tmp-fn+1] = '\0';
 163                                 strcat (buf2, buf); /* plus (relative) symlink */
 164                                 tmp = buf2;
 165                             }
 166                             if (stat(tmp, &tstatbuf) < 0) {
 167                                 ckfprintf(stdout,
 168                                         "broken symbolic link to %s", buf);
 169                                 return 1;
 170                             }
 171                         }
 172
 173                         /* Otherwise, handle it. */
 174                         if (lflag) {
 175                                 process(buf, strlen(buf));
 176                                 return 1;
 177                         } else { /* just print what it points to */
 178                                 ckfputs("symbolic link to ", stdout);
 179                                 ckfputs(buf, stdout);
 180                         }
 181                 }
 182                 return 1;
 183 #endif
 184 #ifdef  S_IFSOCK
 185 #ifndef __COHERENT__
 186         case S_IFSOCK:
 187                 ckfputs("socket", stdout);
 188                 return 1;
 189 #endif
 190 #endif
 191         case S_IFREG:
 192                 break;
 193         default:
 194                 error("invalid mode 0%o.\n", sb->st_mode);
 195                 /*NOTREACHED*/
 196         }
 197
 198         /*
 199          * regular file, check next possibility
 200          */
 201         if (sb->st_size == 0) {
 202                 ckfputs("empty", stdout);
 203                 return 1;
 204         }
 205         return 0;
 206 }
 207