src/mv.c

   1 /* mv -- move or rename files
   2    Copyright (C) 1986-2012 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 3 of the License, or
   7    (at your option) 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, see <http://www.gnu.org/licenses/>.  */
  16
  17 /* Written by Mike Parker, David MacKenzie, and Jim Meyering */
  18
  19 #include <config.h>
  20 #include <stdio.h>
  21 #include <getopt.h>
  22 #include <sys/types.h>
  23 #include <assert.h>
  24 #include <selinux/selinux.h>
  25
  26 #include "system.h"
  27 #include "backupfile.h"
  28 #include "copy.h"
  29 #include "cp-hash.h"
  30 #include "error.h"
  31 #include "filenamecat.h"
  32 #include "quote.h"
  33 #include "remove.h"
  34 #include "root-dev-ino.h"
  35 #include "priv-set.h"
  36
  37 /* The official name of this program (e.g., no 'g' prefix).  */
  38 #define PROGRAM_NAME "mv"
  39
  40 #define AUTHORS \
  41   proper_name ("Mike Parker"), \
  42   proper_name ("David MacKenzie"), \
  43   proper_name ("Jim Meyering")
  44
  45 /* For long options that have no equivalent short option, use a
  46    non-character as a pseudo short option, starting with CHAR_MAX + 1.  */
  47 enum
  48 {
  49   STRIP_TRAILING_SLASHES_OPTION = CHAR_MAX + 1
  50 };
  51
  52 /* Remove any trailing slashes from each SOURCE argument.  */
  53 static bool remove_trailing_slashes;
  54
  55 static struct option const long_options[] =
  56 {
  57   {"backup", optional_argument, NULL, 'b'},
  58   {"force", no_argument, NULL, 'f'},
  59   {"interactive", no_argument, NULL, 'i'},
  60   {"no-clobber", no_argument, NULL, 'n'},
  61   {"no-target-directory", no_argument, NULL, 'T'},
  62   {"strip-trailing-slashes", no_argument, NULL, STRIP_TRAILING_SLASHES_OPTION},
  63   {"suffix", required_argument, NULL, 'S'},
  64   {"target-directory", required_argument, NULL, 't'},
  65   {"update", no_argument, NULL, 'u'},
  66   {"verbose", no_argument, NULL, 'v'},
  67   {GETOPT_HELP_OPTION_DECL},
  68   {GETOPT_VERSION_OPTION_DECL},
  69   {NULL, 0, NULL, 0}
  70 };
  71
  72 static void
  73 rm_option_init (struct rm_options *x)
  74 {
  75   x->ignore_missing_files = false;
  76   x->recursive = true;
  77   x->one_file_system = false;
  78
  79   /* Should we prompt for removal, too?  No.  Prompting for the 'move'
  80      part is enough.  It implies removal.  */
  81   x->interactive = RMI_NEVER;
  82   x->stdin_tty = false;
  83
  84   x->verbose = false;
  85
  86   /* Since this program may well have to process additional command
  87      line arguments after any call to 'rm', that function must preserve
  88      the initial working directory, in case one of those is a
  89      '.'-relative name.  */
  90   x->require_restore_cwd = true;
  91
  92   {
  93     static struct dev_ino dev_ino_buf;
  94     x->root_dev_ino = get_root_dev_ino (&dev_ino_buf);
  95     if (x->root_dev_ino == NULL)
  96       error (EXIT_FAILURE, errno, _("failed to get attributes of %s"),
  97              quote ("/"));
  98   }
  99 }
 100
 101 static void
 102 cp_option_init (struct cp_options *x)
 103 {
 104   bool selinux_enabled = (0 < is_selinux_enabled ());
 105
 106   cp_options_default (x);
 107   x->copy_as_regular = false;  /* FIXME: maybe make this an option */
 108   x->reflink_mode = REFLINK_NEVER;
 109   x->dereference = DEREF_NEVER;
 110   x->unlink_dest_before_opening = false;
 111   x->unlink_dest_after_failed_open = false;
 112   x->hard_link = false;
 113   x->interactive = I_UNSPECIFIED;
 114   x->move_mode = true;
 115   x->one_file_system = false;
 116   x->preserve_ownership = true;
 117   x->preserve_links = true;
 118   x->preserve_mode = true;
 119   x->preserve_timestamps = true;
 120   x->preserve_security_context = selinux_enabled;
 121   x->reduce_diagnostics = false;
 122   x->data_copy_required = true;
 123   x->require_preserve = false;  /* FIXME: maybe make this an option */
 124   x->require_preserve_context = false;
 125   x->preserve_xattr = true;
 126   x->require_preserve_xattr = false;
 127   x->recursive = true;
 128   x->sparse_mode = SPARSE_AUTO;  /* FIXME: maybe make this an option */
 129   x->symbolic_link = false;
 130   x->set_mode = false;
 131   x->mode = 0;
 132   x->stdin_tty = isatty (STDIN_FILENO);
 133
 134   x->open_dangling_dest_symlink = false;
 135   x->update = false;
 136   x->verbose = false;
 137   x->dest_info = NULL;
 138   x->src_info = NULL;
 139 }
 140
 141 /* FILE is the last operand of this command.  Return true if FILE is a
 142    directory.  But report an error if there is a problem accessing FILE, other
 143    than nonexistence (errno == ENOENT).  */
 144
 145 static bool
 146 target_directory_operand (char const *file)
 147 {
 148   struct stat st;
 149   int err = (stat (file, &st) == 0 ? 0 : errno);
 150   bool is_a_dir = !err && S_ISDIR (st.st_mode);
 151   if (err && err != ENOENT)
 152     error (EXIT_FAILURE, err, _("accessing %s"), quote (file));
 153   return is_a_dir;
 154 }
 155
 156 /* Move SOURCE onto DEST.  Handles cross-file-system moves.
 157    If SOURCE is a directory, DEST must not exist.
 158    Return true if successful.  */
 159
 160 static bool
 161 do_move (const char *source, const char *dest, const struct cp_options *x)
 162 {
 163   bool copy_into_self;
 164   bool rename_succeeded;
 165   bool ok = copy (source, dest, false, x, &copy_into_self, &rename_succeeded);
 166
 167   if (ok)
 168     {
 169       char const *dir_to_remove;
 170       if (copy_into_self)
 171         {
 172           /* In general, when copy returns with copy_into_self set, SOURCE is
 173              the same as, or a parent of DEST.  In this case we know it's a
 174              parent.  It doesn't make sense to move a directory into itself, and
 175              besides in some situations doing so would give highly nonintuitive
 176              results.  Run this 'mkdir b; touch a c; mv * b' in an empty
 177              directory.  Here's the result of running echo `find b -print`:
 178              b b/a b/b b/b/a b/c.  Notice that only file 'a' was copied
 179              into b/b.  Handle this by giving a diagnostic, removing the
 180              copied-into-self directory, DEST ('b/b' in the example),
 181              and failing.  */
 182
 183           dir_to_remove = NULL;
 184           ok = false;
 185         }
 186       else if (rename_succeeded)
 187         {
 188           /* No need to remove anything.  SOURCE was successfully
 189              renamed to DEST.  Or the user declined to rename a file.  */
 190           dir_to_remove = NULL;
 191         }
 192       else
 193         {
 194           /* This may mean SOURCE and DEST referred to different devices.
 195              It may also conceivably mean that even though they referred
 196              to the same device, rename wasn't implemented for that device.
 197
 198              E.g., (from Joel N. Weber),
 199              [...] there might someday be cases where you can't rename
 200              but you can copy where the device name is the same, especially
 201              on Hurd.  Consider an ftpfs with a primitive ftp server that
 202              supports uploading, downloading and deleting, but not renaming.
 203
 204              Also, note that comparing device numbers is not a reliable
 205              check for 'can-rename'.  Some systems can be set up so that
 206              files from many different physical devices all have the same
 207              st_dev field.  This is a feature of some NFS mounting
 208              configurations.
 209
 210              We reach this point if SOURCE has been successfully copied
 211              to DEST.  Now we have to remove SOURCE.
 212
 213              This function used to resort to copying only when rename
 214              failed and set errno to EXDEV.  */
 215
 216           dir_to_remove = source;
 217         }
 218
 219       if (dir_to_remove != NULL)
 220         {
 221           struct rm_options rm_options;
 222           enum RM_status status;
 223           char const *dir[2];
 224
 225           rm_option_init (&rm_options);
 226           rm_options.verbose = x->verbose;
 227           dir[0] = dir_to_remove;
 228           dir[1] = NULL;
 229
 230           status = rm ((void*) dir, &rm_options);
 231           assert (VALID_STATUS (status));
 232           if (status == RM_ERROR)
 233             ok = false;
 234         }
 235     }
 236
 237   return ok;
 238 }
 239
 240 /* Move file SOURCE onto DEST.  Handles the case when DEST is a directory.
 241    Treat DEST as a directory if DEST_IS_DIR.
 242    Return true if successful.  */
 243
 244 static bool
 245 movefile (char *source, char *dest, bool dest_is_dir,
 246           const struct cp_options *x)
 247 {
 248   bool ok;
 249
 250   /* This code was introduced to handle the ambiguity in the semantics
 251      of mv that is induced by the varying semantics of the rename function.
 252      Some systems (e.g., GNU/Linux) have a rename function that honors a
 253      trailing slash, while others (like Solaris 5,6,7) have a rename
 254      function that ignores a trailing slash.  I believe the GNU/Linux
 255      rename semantics are POSIX and susv2 compliant.  */
 256
 257   if (remove_trailing_slashes)
 258     strip_trailing_slashes (source);
 259
 260   if (dest_is_dir)
 261     {
 262       /* Treat DEST as a directory; build the full filename.  */
 263       char const *src_basename = last_component (source);
 264       char *new_dest = file_name_concat (dest, src_basename, NULL);
 265       strip_trailing_slashes (new_dest);
 266       ok = do_move (source, new_dest, x);
 267       free (new_dest);
 268     }
 269   else
 270     {
 271       ok = do_move (source, dest, x);
 272     }
 273
 274   return ok;
 275 }
 276
 277 void
 278 usage (int status)
 279 {
 280   if (status != EXIT_SUCCESS)
 281     emit_try_help ();
 282   else
 283     {
 284       printf (_("\
 285 Usage: %s [OPTION]... [-T] SOURCE DEST\n\
 286   or:  %s [OPTION]... SOURCE... DIRECTORY\n\
 287   or:  %s [OPTION]... -t DIRECTORY SOURCE...\n\
 288 "),
 289               program_name, program_name, program_name);
 290       fputs (_("\
 291 Rename SOURCE to DEST, or move SOURCE(s) to DIRECTORY.\n\
 292 \n\
 293 "), stdout);
 294       fputs (_("\
 295 Mandatory arguments to long options are mandatory for short options too.\n\
 296 "), stdout);
 297       fputs (_("\
 298       --backup[=CONTROL]       make a backup of each existing destination file\
 299 \n\
 300   -b                           like --backup but does not accept an argument\n\
 301   -f, --force                  do not prompt before overwriting\n\
 302   -i, --interactive            prompt before overwrite\n\
 303   -n, --no-clobber             do not overwrite an existing file\n\
 304 If you specify more than one of -i, -f, -n, only the final one takes effect.\n\
 305 "), stdout);
 306       fputs (_("\
 307       --strip-trailing-slashes  remove any trailing slashes from each SOURCE\n\
 308                                  argument\n\
 309   -S, --suffix=SUFFIX          override the usual backup suffix\n\
 310 "), stdout);
 311       fputs (_("\
 312   -t, --target-directory=DIRECTORY  move all SOURCE arguments into DIRECTORY\n\
 313   -T, --no-target-directory    treat DEST as a normal file\n\
 314   -u, --update                 move only when the SOURCE file is newer\n\
 315                                  than the destination file or when the\n\
 316                                  destination file is missing\n\
 317   -v, --verbose                explain what is being done\n\
 318 "), stdout);
 319       fputs (HELP_OPTION_DESCRIPTION, stdout);
 320       fputs (VERSION_OPTION_DESCRIPTION, stdout);
 321       fputs (_("\
 322 \n\
 323 The backup suffix is '~', unless set with --suffix or SIMPLE_BACKUP_SUFFIX.\n\
 324 The version control method may be selected via the --backup option or through\n\
 325 the VERSION_CONTROL environment variable.  Here are the values:\n\
 326 \n\
 327 "), stdout);
 328       fputs (_("\
 329   none, off       never make backups (even if --backup is given)\n\
 330   numbered, t     make numbered backups\n\
 331   existing, nil   numbered if numbered backups exist, simple otherwise\n\
 332   simple, never   always make simple backups\n\
 333 "), stdout);
 334       emit_ancillary_info ();
 335     }
 336   exit (status);
 337 }
 338
 339 int
 340 main (int argc, char **argv)
 341 {
 342   int c;
 343   bool ok;
 344   bool make_backups = false;
 345   char *backup_suffix_string;
 346   char *version_control_string = NULL;
 347   struct cp_options x;
 348   char *target_directory = NULL;
 349   bool no_target_directory = false;
 350   int n_files;
 351   char **file;
 352
 353   initialize_main (&argc, &argv);
 354   set_program_name (argv[0]);
 355   setlocale (LC_ALL, "");
 356   bindtextdomain (PACKAGE, LOCALEDIR);
 357   textdomain (PACKAGE);
 358
 359   atexit (close_stdin);
 360
 361   cp_option_init (&x);
 362
 363   /* Try to disable the ability to unlink a directory.  */
 364   priv_set_remove_linkdir ();
 365
 366   /* FIXME: consider not calling getenv for SIMPLE_BACKUP_SUFFIX unless
 367      we'll actually use backup_suffix_string.  */
 368   backup_suffix_string = getenv ("SIMPLE_BACKUP_SUFFIX");
 369
 370   while ((c = getopt_long (argc, argv, "bfint:uvS:T", long_options, NULL))
 371          != -1)
 372     {
 373       switch (c)
 374         {
 375         case 'b':
 376           make_backups = true;
 377           if (optarg)
 378             version_control_string = optarg;
 379           break;
 380         case 'f':
 381           x.interactive = I_ALWAYS_YES;
 382           break;
 383         case 'i':
 384           x.interactive = I_ASK_USER;
 385           break;
 386         case 'n':
 387           x.interactive = I_ALWAYS_NO;
 388           break;
 389         case STRIP_TRAILING_SLASHES_OPTION:
 390           remove_trailing_slashes = true;
 391           break;
 392         case 't':
 393           if (target_directory)
 394             error (EXIT_FAILURE, 0, _("multiple target directories specified"));
 395           else
 396             {
 397               struct stat st;
 398               if (stat (optarg, &st) != 0)
 399                 error (EXIT_FAILURE, errno, _("accessing %s"), quote (optarg));
 400               if (! S_ISDIR (st.st_mode))
 401                 error (EXIT_FAILURE, 0, _("target %s is not a directory"),
 402                        quote (optarg));
 403             }
 404           target_directory = optarg;
 405           break;
 406         case 'T':
 407           no_target_directory = true;
 408           break;
 409         case 'u':
 410           x.update = true;
 411           break;
 412         case 'v':
 413           x.verbose = true;
 414           break;
 415         case 'S':
 416           make_backups = true;
 417           backup_suffix_string = optarg;
 418           break;
 419         case_GETOPT_HELP_CHAR;
 420         case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
 421         default:
 422           usage (EXIT_FAILURE);
 423         }
 424     }
 425
 426   n_files = argc - optind;
 427   file = argv + optind;
 428
 429   if (n_files <= !target_directory)
 430     {
 431       if (n_files <= 0)
 432         error (0, 0, _("missing file operand"));
 433       else
 434         error (0, 0, _("missing destination file operand after %s"),
 435                quote (file[0]));
 436       usage (EXIT_FAILURE);
 437     }
 438
 439   if (no_target_directory)
 440     {
 441       if (target_directory)
 442         error (EXIT_FAILURE, 0,
 443                _("cannot combine --target-directory (-t) "
 444                  "and --no-target-directory (-T)"));
 445       if (2 < n_files)
 446         {
 447           error (0, 0, _("extra operand %s"), quote (file[2]));
 448           usage (EXIT_FAILURE);
 449         }
 450     }
 451   else if (!target_directory)
 452     {
 453       assert (2 <= n_files);
 454       if (target_directory_operand (file[n_files - 1]))
 455         target_directory = file[--n_files];
 456       else if (2 < n_files)
 457         error (EXIT_FAILURE, 0, _("target %s is not a directory"),
 458                quote (file[n_files - 1]));
 459     }
 460
 461   if (make_backups && x.interactive == I_ALWAYS_NO)
 462     {
 463       error (0, 0,
 464              _("options --backup and --no-clobber are mutually exclusive"));
 465       usage (EXIT_FAILURE);
 466     }
 467
 468   if (backup_suffix_string)
 469     simple_backup_suffix = xstrdup (backup_suffix_string);
 470
 471   x.backup_type = (make_backups
 472                    ? xget_version (_("backup type"),
 473                                    version_control_string)
 474                    : no_backups);
 475
 476   hash_init ();
 477
 478   if (target_directory)
 479     {
 480       int i;
 481
 482       /* Initialize the hash table only if we'll need it.
 483          The problem it is used to detect can arise only if there are
 484          two or more files to move.  */
 485       if (2 <= n_files)
 486         dest_info_init (&x);
 487
 488       ok = true;
 489       for (i = 0; i < n_files; ++i)
 490         ok &= movefile (file[i], target_directory, true, &x);
 491     }
 492   else
 493     ok = movefile (file[0], file[1], false, &x);
 494
 495   exit (ok ? EXIT_SUCCESS : EXIT_FAILURE);
 496 }