src/mv.c

   1 /* mv -- move or rename files
   2    Copyright (C) 1986, 1989-1991, 1995-2011 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     fprintf (stderr, _("Try `%s --help' for more information.\n"),
 282              program_name);
 283   else
 284     {
 285       printf (_("\
 286 Usage: %s [OPTION]... [-T] SOURCE DEST\n\
 287   or:  %s [OPTION]... SOURCE... DIRECTORY\n\
 288   or:  %s [OPTION]... -t DIRECTORY SOURCE...\n\
 289 "),
 290               program_name, program_name, program_name);
 291       fputs (_("\
 292 Rename SOURCE to DEST, or move SOURCE(s) to DIRECTORY.\n\
 293 \n\
 294 "), stdout);
 295       fputs (_("\
 296 Mandatory arguments to long options are mandatory for short options too.\n\
 297 "), stdout);
 298       fputs (_("\
 299       --backup[=CONTROL]       make a backup of each existing destination file\
 300 \n\
 301   -b                           like --backup but does not accept an argument\n\
 302   -f, --force                  do not prompt before overwriting\n\
 303   -i, --interactive            prompt before overwrite\n\
 304   -n, --no-clobber             do not overwrite an existing file\n\
 305 If you specify more than one of -i, -f, -n, only the final one takes effect.\n\
 306 "), stdout);
 307       fputs (_("\
 308       --strip-trailing-slashes  remove any trailing slashes from each SOURCE\n\
 309                                  argument\n\
 310   -S, --suffix=SUFFIX          override the usual backup suffix\n\
 311 "), stdout);
 312       fputs (_("\
 313   -t, --target-directory=DIRECTORY  move all SOURCE arguments into DIRECTORY\n\
 314   -T, --no-target-directory    treat DEST as a normal file\n\
 315   -u, --update                 move only when the SOURCE file is newer\n\
 316                                  than the destination file or when the\n\
 317                                  destination file is missing\n\
 318   -v, --verbose                explain what is being done\n\
 319 "), stdout);
 320       fputs (HELP_OPTION_DESCRIPTION, stdout);
 321       fputs (VERSION_OPTION_DESCRIPTION, stdout);
 322       fputs (_("\
 323 \n\
 324 The backup suffix is `~', unless set with --suffix or SIMPLE_BACKUP_SUFFIX.\n\
 325 The version control method may be selected via the --backup option or through\n\
 326 the VERSION_CONTROL environment variable.  Here are the values:\n\
 327 \n\
 328 "), stdout);
 329       fputs (_("\
 330   none, off       never make backups (even if --backup is given)\n\
 331   numbered, t     make numbered backups\n\
 332   existing, nil   numbered if numbered backups exist, simple otherwise\n\
 333   simple, never   always make simple backups\n\
 334 "), stdout);
 335       emit_ancillary_info ();
 336     }
 337   exit (status);
 338 }
 339
 340 int
 341 main (int argc, char **argv)
 342 {
 343   int c;
 344   bool ok;
 345   bool make_backups = false;
 346   char *backup_suffix_string;
 347   char *version_control_string = NULL;
 348   struct cp_options x;
 349   char *target_directory = NULL;
 350   bool no_target_directory = false;
 351   int n_files;
 352   char **file;
 353
 354   initialize_main (&argc, &argv);
 355   set_program_name (argv[0]);
 356   setlocale (LC_ALL, "");
 357   bindtextdomain (PACKAGE, LOCALEDIR);
 358   textdomain (PACKAGE);
 359
 360   atexit (close_stdin);
 361
 362   cp_option_init (&x);
 363
 364   /* Try to disable the ability to unlink a directory.  */
 365   priv_set_remove_linkdir ();
 366
 367   /* FIXME: consider not calling getenv for SIMPLE_BACKUP_SUFFIX unless
 368      we'll actually use backup_suffix_string.  */
 369   backup_suffix_string = getenv ("SIMPLE_BACKUP_SUFFIX");
 370
 371   while ((c = getopt_long (argc, argv, "bfint:uvS:T", long_options, NULL))
 372          != -1)
 373     {
 374       switch (c)
 375         {
 376         case 'b':
 377           make_backups = true;
 378           if (optarg)
 379             version_control_string = optarg;
 380           break;
 381         case 'f':
 382           x.interactive = I_ALWAYS_YES;
 383           break;
 384         case 'i':
 385           x.interactive = I_ASK_USER;
 386           break;
 387         case 'n':
 388           x.interactive = I_ALWAYS_NO;
 389           break;
 390         case STRIP_TRAILING_SLASHES_OPTION:
 391           remove_trailing_slashes = true;
 392           break;
 393         case 't':
 394           if (target_directory)
 395             error (EXIT_FAILURE, 0, _("multiple target directories specified"));
 396           else
 397             {
 398               struct stat st;
 399               if (stat (optarg, &st) != 0)
 400                 error (EXIT_FAILURE, errno, _("accessing %s"), quote (optarg));
 401               if (! S_ISDIR (st.st_mode))
 402                 error (EXIT_FAILURE, 0, _("target %s is not a directory"),
 403                        quote (optarg));
 404             }
 405           target_directory = optarg;
 406           break;
 407         case 'T':
 408           no_target_directory = true;
 409           break;
 410         case 'u':
 411           x.update = true;
 412           break;
 413         case 'v':
 414           x.verbose = true;
 415           break;
 416         case 'S':
 417           make_backups = true;
 418           backup_suffix_string = optarg;
 419           break;
 420         case_GETOPT_HELP_CHAR;
 421         case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
 422         default:
 423           usage (EXIT_FAILURE);
 424         }
 425     }
 426
 427   n_files = argc - optind;
 428   file = argv + optind;
 429
 430   if (n_files <= !target_directory)
 431     {
 432       if (n_files <= 0)
 433         error (0, 0, _("missing file operand"));
 434       else
 435         error (0, 0, _("missing destination file operand after %s"),
 436                quote (file[0]));
 437       usage (EXIT_FAILURE);
 438     }
 439
 440   if (no_target_directory)
 441     {
 442       if (target_directory)
 443         error (EXIT_FAILURE, 0,
 444                _("cannot combine --target-directory (-t) "
 445                  "and --no-target-directory (-T)"));
 446       if (2 < n_files)
 447         {
 448           error (0, 0, _("extra operand %s"), quote (file[2]));
 449           usage (EXIT_FAILURE);
 450         }
 451     }
 452   else if (!target_directory)
 453     {
 454       assert (2 <= n_files);
 455       if (target_directory_operand (file[n_files - 1]))
 456         target_directory = file[--n_files];
 457       else if (2 < n_files)
 458         error (EXIT_FAILURE, 0, _("target %s is not a directory"),
 459                quote (file[n_files - 1]));
 460     }
 461
 462   if (make_backups && x.interactive == I_ALWAYS_NO)
 463     {
 464       error (0, 0,
 465              _("options --backup and --no-clobber are mutually exclusive"));
 466       usage (EXIT_FAILURE);
 467     }
 468
 469   if (backup_suffix_string)
 470     simple_backup_suffix = xstrdup (backup_suffix_string);
 471
 472   x.backup_type = (make_backups
 473                    ? xget_version (_("backup type"),
 474                                    version_control_string)
 475                    : no_backups);
 476
 477   hash_init ();
 478
 479   if (target_directory)
 480     {
 481       int i;
 482
 483       /* Initialize the hash table only if we'll need it.
 484          The problem it is used to detect can arise only if there are
 485          two or more files to move.  */
 486       if (2 <= n_files)
 487         dest_info_init (&x);
 488
 489       ok = true;
 490       for (i = 0; i < n_files; ++i)
 491         ok &= movefile (file[i], target_directory, true, &x);
 492     }
 493   else
 494     ok = movefile (file[0], file[1], false, &x);
 495
 496   exit (ok ? EXIT_SUCCESS : EXIT_FAILURE);
 497 }