src/chown.c

   1 /* chown -- change user and group ownership of files
   2    Copyright (C) 89, 90, 91, 1995-2004 Free Software Foundation, Inc.
   3
   4    This program is free software; you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation; either version 2, or (at your option)
   7    any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program; if not, write to the Free Software Foundation,
  16    Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  17
  18 /*
  19               |                       user
  20               | unchanged                 explicit
  21  -------------|-------------------------+-------------------------|
  22  g unchanged  | ---                     | chown u                 |
  23  r            |-------------------------+-------------------------|
  24  o explicit   | chgrp g or chown .g     | chown u.g               |
  25  u            |-------------------------+-------------------------|
  26  p from passwd| ---                     | chown u.                |
  27               |-------------------------+-------------------------|
  28
  29    Written by David MacKenzie <djm@gnu.ai.mit.edu>. */
  30
  31 #include <config.h>
  32 #include <stdio.h>
  33 #include <sys/types.h>
  34 #include <getopt.h>
  35
  36 #include "system.h"
  37 #include "chown-core.h"
  38 #include "error.h"
  39 #include "fts_.h"
  40 #include "lchown.h"
  41 #include "quote.h"
  42 #include "root-dev-ino.h"
  43 #include "userspec.h"
  44
  45 /* The official name of this program (e.g., no `g' prefix).  */
  46 #define PROGRAM_NAME "chown"
  47
  48 #define AUTHORS "David MacKenzie", "Jim Meyering"
  49
  50 /* The name the program was run with. */
  51 char *program_name;
  52
  53 /* The argument to the --reference option.  Use the owner and group IDs
  54    of this file.  This file must exist.  */
  55 static char *reference_file;
  56
  57 /* For long options that have no equivalent short option, use a
  58    non-character as a pseudo short option, starting with CHAR_MAX + 1.  */
  59 enum
  60 {
  61   DEREFERENCE_OPTION = CHAR_MAX + 1,
  62   FROM_OPTION,
  63   NO_PRESERVE_ROOT,
  64   PRESERVE_ROOT,
  65   REFERENCE_FILE_OPTION
  66 };
  67
  68 static struct option const long_options[] =
  69 {
  70   {"recursive", no_argument, 0, 'R'},
  71   {"changes", no_argument, 0, 'c'},
  72   {"dereference", no_argument, 0, DEREFERENCE_OPTION},
  73   {"from", required_argument, 0, FROM_OPTION},
  74   {"no-dereference", no_argument, 0, 'h'},
  75   {"no-preserve-root", no_argument, 0, NO_PRESERVE_ROOT},
  76   {"preserve-root", no_argument, 0, PRESERVE_ROOT},
  77   {"quiet", no_argument, 0, 'f'},
  78   {"silent", no_argument, 0, 'f'},
  79   {"reference", required_argument, 0, REFERENCE_FILE_OPTION},
  80   {"verbose", no_argument, 0, 'v'},
  81   {GETOPT_HELP_OPTION_DECL},
  82   {GETOPT_VERSION_OPTION_DECL},
  83   {0, 0, 0, 0}
  84 };
  85
  86 void
  87 usage (int status)
  88 {
  89   if (status != EXIT_SUCCESS)
  90     fprintf (stderr, _("Try `%s --help' for more information.\n"),
  91              program_name);
  92   else
  93     {
  94       printf (_("\
  95 Usage: %s [OPTION]... OWNER[:[GROUP]] FILE...\n\
  96   or:  %s [OPTION]... :GROUP FILE...\n\
  97   or:  %s [OPTION]... --reference=RFILE FILE...\n\
  98 "),
  99               program_name, program_name, program_name);
 100       fputs (_("\
 101 Change the owner and/or group of each FILE to OWNER and/or GROUP.\n\
 102 With --reference, change the owner and group of each FILE to those of RFILE.\n\
 103 \n\
 104   -c, --changes          like verbose but report only when a change is made\n\
 105       --dereference      affect the referent of each symbolic link, rather\n\
 106                          than the symbolic link itself\n\
 107 "), stdout);
 108       fputs (_("\
 109   -h, --no-dereference   affect each symbolic link instead of any referenced\n\
 110                          file (useful only on systems that can change the\n\
 111                          ownership of a symlink)\n\
 112 "), stdout);
 113       fputs (_("\
 114       --from=CURRENT_OWNER:CURRENT_GROUP\n\
 115                          change the owner and/or group of each file only if\n\
 116                          its current owner and/or group match those specified\n\
 117                          here.  Either may be omitted, in which case a match\n\
 118                          is not required for the omitted attribute.\n\
 119 "), stdout);
 120       fputs (_("\
 121       --no-preserve-root do not treat `/' specially (the default)\n\
 122       --preserve-root    fail to operate recursively on `/'\n\
 123 "), stdout);
 124       fputs (_("\
 125   -f, --silent, --quiet  suppress most error messages\n\
 126       --reference=RFILE  use RFILE's owner and group rather than\n\
 127                          the specifying OWNER:GROUP values\n\
 128   -R, --recursive        operate on files and directories recursively\n\
 129   -v, --verbose          output a diagnostic for every file processed\n\
 130 \n\
 131 "), stdout);
 132       fputs (_("\
 133 The following options modify how a hierarchy is traversed when the -R\n\
 134 option is also specified.  If more than one is specified, only the final\n\
 135 one takes effect.\n\
 136 \n\
 137   -H                     if a command line argument is a symbolic link\n\
 138                          to a directory, traverse it\n\
 139   -L                     traverse every symbolic link to a directory\n\
 140                          encountered\n\
 141   -P                     do not traverse any symbolic links (default)\n\
 142 \n\
 143 "), stdout);
 144       fputs (HELP_OPTION_DESCRIPTION, stdout);
 145       fputs (VERSION_OPTION_DESCRIPTION, stdout);
 146       fputs (_("\
 147 \n\
 148 Owner is unchanged if missing.  Group is unchanged if missing, but changed\n\
 149 to login group if implied by a `:'.  OWNER and GROUP may be numeric as well\n\
 150 as symbolic.\n\
 151 "), stdout);
 152       printf (_("\nReport bugs to <%s>.\n"), PACKAGE_BUGREPORT);
 153     }
 154   exit (status);
 155 }
 156
 157 int
 158 main (int argc, char **argv)
 159 {
 160   bool preserve_root = false;
 161
 162   uid_t uid = -1;       /* Specified uid; -1 if not to be changed. */
 163   gid_t gid = -1;       /* Specified gid; -1 if not to be changed. */
 164
 165   /* Change the owner (group) of a file only if it has this uid (gid).
 166      -1 means there's no restriction.  */
 167   uid_t required_uid = -1;
 168   gid_t required_gid = -1;
 169
 170   /* Bit flags that control how fts works.  */
 171   int bit_flags = FTS_PHYSICAL;
 172
 173   struct Chown_option chopt;
 174   int fail;
 175   int optc;
 176
 177   initialize_main (&argc, &argv);
 178   program_name = argv[0];
 179   setlocale (LC_ALL, "");
 180   bindtextdomain (PACKAGE, LOCALEDIR);
 181   textdomain (PACKAGE);
 182
 183   atexit (close_stdout);
 184
 185   chopt_init (&chopt);
 186
 187   while ((optc = getopt_long (argc, argv, "HLPRcfhv", long_options, NULL))
 188          != -1)
 189     {
 190       switch (optc)
 191         {
 192         case 0:
 193           break;
 194
 195         case 'H': /* Traverse command-line symlinks-to-directories.  */
 196           bit_flags = FTS_COMFOLLOW;
 197           break;
 198
 199         case 'L': /* Traverse all symlinks-to-directories.  */
 200           bit_flags = FTS_LOGICAL;
 201           break;
 202
 203         case 'P': /* Traverse no symlinks-to-directories.  */
 204           bit_flags = FTS_PHYSICAL;
 205           break;
 206
 207         case 'h': /* --no-dereference: affect symlinks */
 208           chopt.affect_symlink_referent = false;
 209           break;
 210
 211         case DEREFERENCE_OPTION: /* --dereference: affect the referent
 212                                     of each symlink */
 213           chopt.affect_symlink_referent = true;
 214           break;
 215
 216         case NO_PRESERVE_ROOT:
 217           preserve_root = false;
 218           break;
 219
 220         case PRESERVE_ROOT:
 221           preserve_root = true;
 222           break;
 223
 224         case REFERENCE_FILE_OPTION:
 225           reference_file = optarg;
 226           break;
 227
 228         case FROM_OPTION:
 229           {
 230             char *u_dummy, *g_dummy;
 231             const char *e = parse_user_spec (optarg,
 232                                              &required_uid, &required_gid,
 233                                              &u_dummy, &g_dummy);
 234             if (e)
 235               error (EXIT_FAILURE, 0, "%s: %s", quote (optarg), e);
 236             break;
 237           }
 238
 239         case 'R':
 240           chopt.recurse = true;
 241           break;
 242
 243         case 'c':
 244           chopt.verbosity = V_changes_only;
 245           break;
 246
 247         case 'f':
 248           chopt.force_silent = true;
 249           break;
 250
 251         case 'v':
 252           chopt.verbosity = V_high;
 253           break;
 254
 255         case_GETOPT_HELP_CHAR;
 256         case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
 257         default:
 258           usage (EXIT_FAILURE);
 259         }
 260     }
 261
 262   if (argc - optind + (reference_file ? 1 : 0) <= 1)
 263     {
 264       error (0, 0, _("too few arguments"));
 265       usage (EXIT_FAILURE);
 266     }
 267
 268   if (reference_file)
 269     {
 270       struct stat ref_stats;
 271       if (stat (reference_file, &ref_stats))
 272         error (EXIT_FAILURE, errno, _("failed to get attributes of %s"),
 273                quote (reference_file));
 274
 275       uid = ref_stats.st_uid;
 276       gid = ref_stats.st_gid;
 277       chopt.user_name = uid_to_name (ref_stats.st_uid);
 278       chopt.group_name = gid_to_name (ref_stats.st_gid);
 279     }
 280   else
 281     {
 282       const char *e = parse_user_spec (argv[optind], &uid, &gid,
 283                                        &chopt.user_name, &chopt.group_name);
 284       if (e)
 285         error (EXIT_FAILURE, 0, "%s: %s", quote (argv[optind]), e);
 286
 287       /* FIXME: set it to the empty string?  */
 288       if (chopt.user_name == NULL)
 289         chopt.user_name = "";
 290
 291       optind++;
 292     }
 293
 294   if (chopt.recurse && preserve_root)
 295     {
 296       static struct dev_ino dev_ino_buf;
 297       chopt.root_dev_ino = get_root_dev_ino (&dev_ino_buf);
 298       if (chopt.root_dev_ino == NULL)
 299         error (EXIT_FAILURE, errno, _("failed to get attributes of %s"),
 300                quote ("/"));
 301     }
 302
 303   fail = chown_files (argv + optind, bit_flags,
 304                       uid, gid,
 305                       required_uid, required_gid, &chopt);
 306
 307   chopt_free (&chopt);
 308
 309   exit (fail ? EXIT_FAILURE : EXIT_SUCCESS);
 310 }