src/mv.c

   1 /* mv -- move or rename files
   2    Copyright (C) 1986-2024 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 <https://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 <selinux/label.h>
  24
  25 #include "system.h"
  26 #include "argmatch.h"
  27 #include "assure.h"
  28 #include "backupfile.h"
  29 #include "copy.h"
  30 #include "cp-hash.h"
  31 #include "filenamecat.h"
  32 #include "remove.h"
  33 #include "renameatu.h"
  34 #include "root-dev-ino.h"
  35 #include "targetdir.h"
  36 #include "priv-set.h"
  37
  38 /* The official name of this program (e.g., no 'g' prefix).  */
  39 #define PROGRAM_NAME "mv"
  40
  41 #define AUTHORS \
  42   proper_name ("Mike Parker"), \
  43   proper_name ("David MacKenzie"), \
  44   proper_name ("Jim Meyering")
  45
  46 /* For long options that have no equivalent short option, use a
  47    non-character as a pseudo short option, starting with CHAR_MAX + 1.  */
  48 enum
  49 {
  50   DEBUG_OPTION = CHAR_MAX + 1,
  51   EXCHANGE_OPTION,
  52   NO_COPY_OPTION,
  53   STRIP_TRAILING_SLASHES_OPTION
  54 };
  55
  56 static char const *const update_type_string[] =
  57 {
  58   "all", "none", "none-fail", "older", nullptr
  59 };
  60 static enum Update_type const update_type[] =
  61 {
  62   UPDATE_ALL, UPDATE_NONE, UPDATE_NONE_FAIL, UPDATE_OLDER,
  63 };
  64 ARGMATCH_VERIFY (update_type_string, update_type);
  65
  66 static struct option const long_options[] =
  67 {
  68   {"backup", optional_argument, nullptr, 'b'},
  69   {"context", no_argument, nullptr, 'Z'},
  70   {"debug", no_argument, nullptr, DEBUG_OPTION},
  71   {"exchange", no_argument, nullptr, EXCHANGE_OPTION},
  72   {"force", no_argument, nullptr, 'f'},
  73   {"interactive", no_argument, nullptr, 'i'},
  74   {"no-clobber", no_argument, nullptr, 'n'},   /* Deprecated.  */
  75   {"no-copy", no_argument, nullptr, NO_COPY_OPTION},
  76   {"no-target-directory", no_argument, nullptr, 'T'},
  77   {"strip-trailing-slashes", no_argument, nullptr,
  78    STRIP_TRAILING_SLASHES_OPTION},
  79   {"suffix", required_argument, nullptr, 'S'},
  80   {"target-directory", required_argument, nullptr, 't'},
  81   {"update", optional_argument, nullptr, 'u'},
  82   {"verbose", no_argument, nullptr, 'v'},
  83   {GETOPT_HELP_OPTION_DECL},
  84   {GETOPT_VERSION_OPTION_DECL},
  85   {nullptr, 0, nullptr, 0}
  86 };
  87
  88 static void
  89 rm_option_init (struct rm_options *x)
  90 {
  91   x->ignore_missing_files = false;
  92   x->remove_empty_directories = true;
  93   x->recursive = true;
  94   x->one_file_system = false;
  95
  96   /* Should we prompt for removal, too?  No.  Prompting for the 'move'
  97      part is enough.  It implies removal.  */
  98   x->interactive = RMI_NEVER;
  99   x->stdin_tty = false;
 100
 101   x->verbose = false;
 102
 103   /* Since this program may well have to process additional command
 104      line arguments after any call to 'rm', that function must preserve
 105      the initial working directory, in case one of those is a
 106      '.'-relative name.  */
 107   x->require_restore_cwd = true;
 108
 109   {
 110     static struct dev_ino dev_ino_buf;
 111     x->root_dev_ino = get_root_dev_ino (&dev_ino_buf);
 112     if (x->root_dev_ino == nullptr)
 113       error (EXIT_FAILURE, errno, _("failed to get attributes of %s"),
 114              quoteaf ("/"));
 115   }
 116
 117   x->preserve_all_root = false;
 118 }
 119
 120 static void
 121 cp_option_init (struct cp_options *x)
 122 {
 123   bool selinux_enabled = (0 < is_selinux_enabled ());
 124
 125   cp_options_default (x);
 126   x->copy_as_regular = false;  /* FIXME: maybe make this an option */
 127   x->reflink_mode = REFLINK_AUTO;
 128   x->dereference = DEREF_NEVER;
 129   x->unlink_dest_before_opening = false;
 130   x->unlink_dest_after_failed_open = false;
 131   x->hard_link = false;
 132   x->interactive = I_UNSPECIFIED;
 133   x->move_mode = true;
 134   x->install_mode = false;
 135   x->one_file_system = false;
 136   x->preserve_ownership = true;
 137   x->preserve_links = true;
 138   x->preserve_mode = true;
 139   x->preserve_timestamps = true;
 140   x->explicit_no_preserve_mode= false;
 141   x->preserve_security_context = selinux_enabled;
 142   x->set_security_context = nullptr;
 143   x->reduce_diagnostics = false;
 144   x->data_copy_required = true;
 145   x->require_preserve = false;  /* FIXME: maybe make this an option */
 146   x->require_preserve_context = false;
 147   x->preserve_xattr = true;
 148   x->require_preserve_xattr = false;
 149   x->recursive = true;
 150   x->sparse_mode = SPARSE_AUTO;  /* FIXME: maybe make this an option */
 151   x->symbolic_link = false;
 152   x->set_mode = false;
 153   x->mode = 0;
 154   x->stdin_tty = isatty (STDIN_FILENO);
 155
 156   x->open_dangling_dest_symlink = false;
 157   x->update = false;
 158   x->verbose = false;
 159   x->dest_info = nullptr;
 160   x->src_info = nullptr;
 161 }
 162
 163 /* Move SOURCE onto DEST aka DEST_DIRFD+DEST_RELNAME.
 164    Handle cross-file-system moves.
 165    If SOURCE is a directory, DEST must not exist.
 166    Return true if successful.  */
 167
 168 static bool
 169 do_move (char const *source, char const *dest,
 170          int dest_dirfd, char const *dest_relname, const struct cp_options *x)
 171 {
 172   bool copy_into_self;
 173   bool rename_succeeded;
 174   bool ok = copy (source, dest, dest_dirfd, dest_relname, 0, x,
 175                   &copy_into_self, &rename_succeeded);
 176
 177   if (ok)
 178     {
 179       char const *dir_to_remove;
 180       if (copy_into_self)
 181         {
 182           /* In general, when copy returns with copy_into_self set, SOURCE is
 183              the same as, or a parent of DEST.  In this case we know it's a
 184              parent.  It doesn't make sense to move a directory into itself, and
 185              besides in some situations doing so would give highly unintuitive
 186              results.  Run this 'mkdir b; touch a c; mv * b' in an empty
 187              directory.  Here's the result of running echo $(find b -print):
 188              b b/a b/b b/b/a b/c.  Notice that only file 'a' was copied
 189              into b/b.  Handle this by giving a diagnostic, removing the
 190              copied-into-self directory, DEST ('b/b' in the example),
 191              and failing.  */
 192
 193           dir_to_remove = nullptr;
 194           ok = false;
 195         }
 196       else if (rename_succeeded)
 197         {
 198           /* No need to remove anything.  SOURCE was successfully
 199              renamed to DEST.  Or the user declined to rename a file.  */
 200           dir_to_remove = nullptr;
 201         }
 202       else
 203         {
 204           /* This may mean SOURCE and DEST referred to different devices.
 205              It may also conceivably mean that even though they referred
 206              to the same device, rename wasn't implemented for that device.
 207
 208              E.g., (from Joel N. Weber),
 209              [...] there might someday be cases where you can't rename
 210              but you can copy where the device name is the same, especially
 211              on Hurd.  Consider an ftpfs with a primitive ftp server that
 212              supports uploading, downloading and deleting, but not renaming.
 213
 214              Also, note that comparing device numbers is not a reliable
 215              check for 'can-rename'.  Some systems can be set up so that
 216              files from many different physical devices all have the same
 217              st_dev field.  This is a feature of some NFS mounting
 218              configurations.
 219
 220              We reach this point if SOURCE has been successfully copied
 221              to DEST.  Now we have to remove SOURCE.
 222
 223              This function used to resort to copying only when rename
 224              failed and set errno to EXDEV.  */
 225
 226           dir_to_remove = source;
 227         }
 228
 229       if (dir_to_remove != nullptr)
 230         {
 231           struct rm_options rm_options;
 232           enum RM_status status;
 233           char const *dir[2];
 234
 235           rm_option_init (&rm_options);
 236           rm_options.verbose = x->verbose;
 237           dir[0] = dir_to_remove;
 238           dir[1] = nullptr;
 239
 240           status = rm ((void *) dir, &rm_options);
 241           affirm (VALID_STATUS (status));
 242           if (status == RM_ERROR)
 243             ok = false;
 244         }
 245     }
 246
 247   return ok;
 248 }
 249
 250 void
 251 usage (int status)
 252 {
 253   if (status != EXIT_SUCCESS)
 254     emit_try_help ();
 255   else
 256     {
 257       printf (_("\
 258 Usage: %s [OPTION]... [-T] SOURCE DEST\n\
 259   or:  %s [OPTION]... SOURCE... DIRECTORY\n\
 260   or:  %s [OPTION]... -t DIRECTORY SOURCE...\n\
 261 "),
 262               program_name, program_name, program_name);
 263       fputs (_("\
 264 Rename SOURCE to DEST, or move SOURCE(s) to DIRECTORY.\n\
 265 "), stdout);
 266
 267       emit_mandatory_arg_note ();
 268
 269       fputs (_("\
 270       --backup[=CONTROL]       make a backup of each existing destination file\
 271 \n\
 272   -b                           like --backup but does not accept an argument\n\
 273 "), stdout);
 274       fputs (_("\
 275       --debug                  explain how a file is copied.  Implies -v\n\
 276 "), stdout);
 277       fputs (_("\
 278       --exchange               exchange source and destination\n\
 279 "), stdout);
 280       fputs (_("\
 281   -f, --force                  do not prompt before overwriting\n\
 282   -i, --interactive            prompt before overwrite\n\
 283   -n, --no-clobber             do not overwrite an existing file\n\
 284 If you specify more than one of -i, -f, -n, only the final one takes effect.\n\
 285 "), stdout);
 286       fputs (_("\
 287       --no-copy                do not copy if renaming fails\n\
 288       --strip-trailing-slashes  remove any trailing slashes from each SOURCE\n\
 289                                  argument\n\
 290   -S, --suffix=SUFFIX          override the usual backup suffix\n\
 291 "), stdout);
 292       fputs (_("\
 293   -t, --target-directory=DIRECTORY  move all SOURCE arguments into DIRECTORY\n\
 294   -T, --no-target-directory    treat DEST as a normal file\n\
 295 "), stdout);
 296       fputs (_("\
 297   --update[=UPDATE]            control which existing files are updated;\n\
 298                                  UPDATE={all,none,none-fail,older(default)}.\n\
 299   -u                           equivalent to --update[=older].  See below\n\
 300 "), stdout);
 301       fputs (_("\
 302   -v, --verbose                explain what is being done\n\
 303   -Z, --context                set SELinux security context of destination\n\
 304                                  file to default type\n\
 305 "), stdout);
 306       fputs (HELP_OPTION_DESCRIPTION, stdout);
 307       fputs (VERSION_OPTION_DESCRIPTION, stdout);
 308       emit_update_parameters_note ();
 309       emit_backup_suffix_note ();
 310       emit_ancillary_info (PROGRAM_NAME);
 311     }
 312   exit (status);
 313 }
 314
 315 int
 316 main (int argc, char **argv)
 317 {
 318   int c;
 319   bool ok;
 320   bool make_backups = false;
 321   char const *backup_suffix = nullptr;
 322   char *version_control_string = nullptr;
 323   struct cp_options x;
 324   bool remove_trailing_slashes = false;
 325   char const *target_directory = nullptr;
 326   bool no_target_directory = false;
 327   int n_files;
 328   char **file;
 329   bool selinux_enabled = (0 < is_selinux_enabled ());
 330   bool no_clobber = false;
 331
 332   initialize_main (&argc, &argv);
 333   set_program_name (argv[0]);
 334   setlocale (LC_ALL, "");
 335   bindtextdomain (PACKAGE, LOCALEDIR);
 336   textdomain (PACKAGE);
 337
 338   atexit (close_stdin);
 339
 340   cp_option_init (&x);
 341
 342   /* Try to disable the ability to unlink a directory.  */
 343   priv_set_remove_linkdir ();
 344
 345   while ((c = getopt_long (argc, argv, "bfint:uvS:TZ", long_options, nullptr))
 346          != -1)
 347     {
 348       switch (c)
 349         {
 350         case 'b':
 351           make_backups = true;
 352           if (optarg)
 353             version_control_string = optarg;
 354           break;
 355         case 'f':
 356           x.interactive = I_ALWAYS_YES;
 357           break;
 358         case 'i':
 359           x.interactive = I_ASK_USER;
 360           break;
 361         case 'n':
 362           x.interactive = I_ALWAYS_SKIP;
 363           no_clobber = true;
 364           x.update = false;
 365           break;
 366         case DEBUG_OPTION:
 367           x.debug = x.verbose = true;
 368           break;
 369         case EXCHANGE_OPTION:
 370           x.exchange = true;
 371           break;
 372         case NO_COPY_OPTION:
 373           x.no_copy = true;
 374           break;
 375         case STRIP_TRAILING_SLASHES_OPTION:
 376           remove_trailing_slashes = true;
 377           break;
 378         case 't':
 379           if (target_directory)
 380             error (EXIT_FAILURE, 0, _("multiple target directories specified"));
 381           target_directory = optarg;
 382           break;
 383         case 'T':
 384           no_target_directory = true;
 385           break;
 386         case 'u':
 387           if (! no_clobber)
 388             {
 389               enum Update_type update_opt = UPDATE_OLDER;
 390               if (optarg)
 391                 update_opt = XARGMATCH ("--update", optarg,
 392                                         update_type_string, update_type);
 393               if (update_opt == UPDATE_ALL)
 394                 {
 395                   /* Default mv operation.  */
 396                   x.update = false;
 397                   x.interactive = I_UNSPECIFIED;
 398                 }
 399               else if (update_opt == UPDATE_NONE)
 400                 {
 401                   x.update = false;
 402                   x.interactive = I_ALWAYS_SKIP;
 403                 }
 404               else if (update_opt == UPDATE_NONE_FAIL)
 405                 {
 406                   x.update = false;
 407                   x.interactive = I_ALWAYS_NO;
 408                 }
 409               else if (update_opt == UPDATE_OLDER)
 410                 {
 411                   x.update = true;
 412                   x.interactive = I_UNSPECIFIED;
 413                 }
 414             }
 415           break;
 416         case 'v':
 417           x.verbose = true;
 418           break;
 419         case 'S':
 420           make_backups = true;
 421           backup_suffix = optarg;
 422           break;
 423         case 'Z':
 424           /* As a performance enhancement, don't even bother trying
 425              to "restorecon" when not on an selinux-enabled kernel.  */
 426           if (selinux_enabled)
 427             {
 428               x.preserve_security_context = false;
 429               x.set_security_context = selabel_open (SELABEL_CTX_FILE,
 430                                                      nullptr, 0);
 431               if (! x.set_security_context)
 432                 error (0, errno, _("warning: ignoring --context"));
 433             }
 434           break;
 435         case_GETOPT_HELP_CHAR;
 436         case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
 437         default:
 438           usage (EXIT_FAILURE);
 439         }
 440     }
 441
 442   n_files = argc - optind;
 443   file = argv + optind;
 444
 445   if (n_files <= !target_directory)
 446     {
 447       if (n_files <= 0)
 448         error (0, 0, _("missing file operand"));
 449       else
 450         error (0, 0, _("missing destination file operand after %s"),
 451                quoteaf (file[0]));
 452       usage (EXIT_FAILURE);
 453     }
 454
 455   struct stat sb;
 456   sb.st_mode = 0;
 457   int target_dirfd = AT_FDCWD;
 458   if (no_target_directory)
 459     {
 460       if (target_directory)
 461         error (EXIT_FAILURE, 0,
 462                _("cannot combine --target-directory (-t) "
 463                  "and --no-target-directory (-T)"));
 464       if (2 < n_files)
 465         {
 466           error (0, 0, _("extra operand %s"), quoteaf (file[2]));
 467           usage (EXIT_FAILURE);
 468         }
 469     }
 470   else if (target_directory)
 471     {
 472       target_dirfd = target_directory_operand (target_directory, &sb);
 473       if (! target_dirfd_valid (target_dirfd))
 474         error (EXIT_FAILURE, errno, _("target directory %s"),
 475                quoteaf (target_directory));
 476     }
 477   else
 478     {
 479       char const *lastfile = file[n_files - 1];
 480       if (n_files == 2 && !x.exchange)
 481         x.rename_errno = (renameatu (AT_FDCWD, file[0], AT_FDCWD, lastfile,
 482                                      RENAME_NOREPLACE)
 483                           ? errno : 0);
 484       if (x.rename_errno != 0)
 485         {
 486           int fd = target_directory_operand (lastfile, &sb);
 487           if (target_dirfd_valid (fd))
 488             {
 489               x.rename_errno = -1;
 490               target_dirfd = fd;
 491               target_directory = lastfile;
 492               n_files--;
 493             }
 494           else
 495             {
 496               /* The last operand LASTFILE cannot be opened as a directory.
 497                  If there are more than two operands, report an error.
 498
 499                  Also, report an error if LASTFILE is known to be a directory
 500                  even though it could not be opened, which can happen if
 501                  opening failed with EACCES on a platform lacking O_PATH.
 502                  In this case use stat to test whether LASTFILE is a
 503                  directory, in case opening a non-directory with (O_SEARCH
 504                  | O_DIRECTORY) failed with EACCES not ENOTDIR.  */
 505               int err = errno;
 506               if (2 < n_files
 507                   || (O_PATHSEARCH == O_SEARCH && err == EACCES
 508                       && (sb.st_mode != 0 || stat (lastfile, &sb) == 0)
 509                       && S_ISDIR (sb.st_mode)))
 510                 error (EXIT_FAILURE, err, _("target %s"), quoteaf (lastfile));
 511             }
 512         }
 513     }
 514
 515   /* Handle the ambiguity in the semantics of mv induced by the
 516      varying semantics of the rename function.  POSIX-compatible
 517      systems (e.g., GNU/Linux) have a rename function that honors a
 518      trailing slash in the source, while others (Solaris 9, FreeBSD
 519      7.2) have a rename function that ignores it.  */
 520   if (remove_trailing_slashes)
 521     for (int i = 0; i < n_files; i++)
 522       strip_trailing_slashes (file[i]);
 523
 524   if (make_backups
 525       && (x.exchange
 526           || x.interactive == I_ALWAYS_SKIP
 527           || x.interactive == I_ALWAYS_NO))
 528     {
 529       error (0, 0,
 530              _("cannot combine --backup with "
 531                "--exchange, -n, or --update=none-fail"));
 532       usage (EXIT_FAILURE);
 533     }
 534
 535   x.backup_type = (make_backups
 536                    ? xget_version (_("backup type"),
 537                                    version_control_string)
 538                    : no_backups);
 539   set_simple_backup_suffix (backup_suffix);
 540
 541   hash_init ();
 542
 543   if (target_directory)
 544     {
 545       /* Initialize the hash table only if we'll need it.
 546          The problem it is used to detect can arise only if there are
 547          two or more files to move.  */
 548       if (2 <= n_files)
 549         dest_info_init (&x);
 550
 551       ok = true;
 552       for (int i = 0; i < n_files; ++i)
 553         {
 554           x.last_file = i + 1 == n_files;
 555           char const *source = file[i];
 556           char const *source_basename = last_component (source);
 557           char *dest_relname;
 558           char *dest = file_name_concat (target_directory, source_basename,
 559                                          &dest_relname);
 560           strip_trailing_slashes (dest_relname);
 561           ok &= do_move (source, dest, target_dirfd, dest_relname, &x);
 562           free (dest);
 563         }
 564     }
 565   else
 566     {
 567       x.last_file = true;
 568       ok = do_move (file[0], file[1], AT_FDCWD, file[1], &x);
 569     }
 570
 571   main_exit (ok ? EXIT_SUCCESS : EXIT_FAILURE);
 572 }