src/rm.c

   1 /* 'rm' file deletion utility for GNU.
   2    Copyright (C) 1988-2022 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 /* Initially written by Paul Rubin, David MacKenzie, and Richard Stallman.
  18    Reworked to use chdir and avoid recursion, and later, rewritten
  19    once again, to use fts, by Jim Meyering.  */
  20
  21 #include <config.h>
  22 #include <stdio.h>
  23 #include <getopt.h>
  24 #include <sys/types.h>
  25 #include <assert.h>
  26
  27 #include "system.h"
  28 #include "argmatch.h"
  29 #include "die.h"
  30 #include "error.h"
  31 #include "remove.h"
  32 #include "root-dev-ino.h"
  33 #include "yesno.h"
  34 #include "priv-set.h"
  35
  36 /* The official name of this program (e.g., no 'g' prefix).  */
  37 #define PROGRAM_NAME "rm"
  38
  39 #define AUTHORS \
  40   proper_name ("Paul Rubin"), \
  41   proper_name ("David MacKenzie"), \
  42   proper_name ("Richard M. Stallman"), \
  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   INTERACTIVE_OPTION = CHAR_MAX + 1,
  50   ONE_FILE_SYSTEM,
  51   NO_PRESERVE_ROOT,
  52   PRESERVE_ROOT,
  53   PRESUME_INPUT_TTY_OPTION
  54 };
  55
  56 enum interactive_type
  57   {
  58     interactive_never,          /* 0: no option or --interactive=never */
  59     interactive_once,           /* 1: -I or --interactive=once */
  60     interactive_always          /* 2: default, -i or --interactive=always */
  61   };
  62
  63 static struct option const long_opts[] =
  64 {
  65   {"force", no_argument, NULL, 'f'},
  66   {"interactive", optional_argument, NULL, INTERACTIVE_OPTION},
  67
  68   {"one-file-system", no_argument, NULL, ONE_FILE_SYSTEM},
  69   {"no-preserve-root", no_argument, NULL, NO_PRESERVE_ROOT},
  70   {"preserve-root", optional_argument, NULL, PRESERVE_ROOT},
  71
  72   /* This is solely for testing.  Do not document.  */
  73   /* It is relatively difficult to ensure that there is a tty on stdin.
  74      Since rm acts differently depending on that, without this option,
  75      it'd be harder to test the parts of rm that depend on that setting.  */
  76   {"-presume-input-tty", no_argument, NULL, PRESUME_INPUT_TTY_OPTION},
  77
  78   {"recursive", no_argument, NULL, 'r'},
  79   {"dir", no_argument, NULL, 'd'},
  80   {"verbose", no_argument, NULL, 'v'},
  81   {GETOPT_HELP_OPTION_DECL},
  82   {GETOPT_VERSION_OPTION_DECL},
  83   {NULL, 0, NULL, 0}
  84 };
  85
  86 static char const *const interactive_args[] =
  87 {
  88   "never", "no", "none",
  89   "once",
  90   "always", "yes", NULL
  91 };
  92 static enum interactive_type const interactive_types[] =
  93 {
  94   interactive_never, interactive_never, interactive_never,
  95   interactive_once,
  96   interactive_always, interactive_always
  97 };
  98 ARGMATCH_VERIFY (interactive_args, interactive_types);
  99
 100 /* Advise the user about invalid usages like "rm -foo" if the file
 101    "-foo" exists, assuming ARGC and ARGV are as with 'main'.  */
 102
 103 static void
 104 diagnose_leading_hyphen (int argc, char **argv)
 105 {
 106   /* OPTIND is unreliable, so iterate through the arguments looking
 107      for a file name that looks like an option.  */
 108
 109   for (int i = 1; i < argc; i++)
 110     {
 111       char const *arg = argv[i];
 112       struct stat st;
 113
 114       if (arg[0] == '-' && arg[1] && lstat (arg, &st) == 0)
 115         {
 116           fprintf (stderr,
 117                    _("Try '%s ./%s' to remove the file %s.\n"),
 118                    argv[0],
 119                    quotearg_n_style (1, shell_escape_quoting_style, arg),
 120                    quoteaf (arg));
 121           break;
 122         }
 123     }
 124 }
 125
 126 void
 127 usage (int status)
 128 {
 129   if (status != EXIT_SUCCESS)
 130     emit_try_help ();
 131   else
 132     {
 133       printf (_("Usage: %s [OPTION]... [FILE]...\n"), program_name);
 134       fputs (_("\
 135 Remove (unlink) the FILE(s).\n\
 136 \n\
 137   -f, --force           ignore nonexistent files and arguments, never prompt\n\
 138   -i                    prompt before every removal\n\
 139 "), stdout);
 140       fputs (_("\
 141   -I                    prompt once before removing more than three files, or\n\
 142                           when removing recursively; less intrusive than -i,\n\
 143                           while still giving protection against most mistakes\n\
 144       --interactive[=WHEN]  prompt according to WHEN: never, once (-I), or\n\
 145                           always (-i); without WHEN, prompt always\n\
 146 "), stdout);
 147       fputs (_("\
 148       --one-file-system  when removing a hierarchy recursively, skip any\n\
 149                           directory that is on a file system different from\n\
 150                           that of the corresponding command line argument\n\
 151 "), stdout);
 152       fputs (_("\
 153       --no-preserve-root  do not treat '/' specially\n\
 154       --preserve-root[=all]  do not remove '/' (default);\n\
 155                               with 'all', reject any command line argument\n\
 156                               on a separate device from its parent\n\
 157 "), stdout);
 158       fputs (_("\
 159   -r, -R, --recursive   remove directories and their contents recursively\n\
 160   -d, --dir             remove empty directories\n\
 161   -v, --verbose         explain what is being done\n\
 162 "), stdout);
 163       fputs (HELP_OPTION_DESCRIPTION, stdout);
 164       fputs (VERSION_OPTION_DESCRIPTION, stdout);
 165       fputs (_("\
 166 \n\
 167 By default, rm does not remove directories.  Use the --recursive (-r or -R)\n\
 168 option to remove each listed directory, too, along with all of its contents.\n\
 169 "), stdout);
 170       printf (_("\
 171 \n\
 172 To remove a file whose name starts with a '-', for example '-foo',\n\
 173 use one of these commands:\n\
 174   %s -- -foo\n\
 175 \n\
 176   %s ./-foo\n\
 177 "),
 178               program_name, program_name);
 179       fputs (_("\
 180 \n\
 181 Note that if you use rm to remove a file, it might be possible to recover\n\
 182 some of its contents, given sufficient expertise and/or time.  For greater\n\
 183 assurance that the contents are truly unrecoverable, consider using shred(1).\n\
 184 "), stdout);
 185       emit_ancillary_info (PROGRAM_NAME);
 186     }
 187   exit (status);
 188 }
 189
 190 static void
 191 rm_option_init (struct rm_options *x)
 192 {
 193   x->ignore_missing_files = false;
 194   x->interactive = RMI_SOMETIMES;
 195   x->one_file_system = false;
 196   x->remove_empty_directories = false;
 197   x->recursive = false;
 198   x->root_dev_ino = NULL;
 199   x->preserve_all_root = false;
 200   x->stdin_tty = isatty (STDIN_FILENO);
 201   x->verbose = false;
 202
 203   /* Since this program exits immediately after calling 'rm', rm need not
 204      expend unnecessary effort to preserve the initial working directory.  */
 205   x->require_restore_cwd = false;
 206 }
 207
 208 int
 209 main (int argc, char **argv)
 210 {
 211   bool preserve_root = true;
 212   struct rm_options x;
 213   bool prompt_once = false;
 214   int c;
 215
 216   initialize_main (&argc, &argv);
 217   set_program_name (argv[0]);
 218   setlocale (LC_ALL, "");
 219   bindtextdomain (PACKAGE, LOCALEDIR);
 220   textdomain (PACKAGE);
 221
 222   atexit (close_stdin);
 223
 224   rm_option_init (&x);
 225
 226   /* Try to disable the ability to unlink a directory.  */
 227   priv_set_remove_linkdir ();
 228
 229   while ((c = getopt_long (argc, argv, "dfirvIR", long_opts, NULL)) != -1)
 230     {
 231       switch (c)
 232         {
 233         case 'd':
 234           x.remove_empty_directories = true;
 235           break;
 236
 237         case 'f':
 238           x.interactive = RMI_NEVER;
 239           x.ignore_missing_files = true;
 240           prompt_once = false;
 241           break;
 242
 243         case 'i':
 244           x.interactive = RMI_ALWAYS;
 245           x.ignore_missing_files = false;
 246           prompt_once = false;
 247           break;
 248
 249         case 'I':
 250           x.interactive = RMI_SOMETIMES;
 251           x.ignore_missing_files = false;
 252           prompt_once = true;
 253           break;
 254
 255         case 'r':
 256         case 'R':
 257           x.recursive = true;
 258           break;
 259
 260         case INTERACTIVE_OPTION:
 261           {
 262             int i;
 263             if (optarg)
 264               i = XARGMATCH ("--interactive", optarg, interactive_args,
 265                              interactive_types);
 266             else
 267               i = interactive_always;
 268             switch (i)
 269               {
 270               case interactive_never:
 271                 x.interactive = RMI_NEVER;
 272                 prompt_once = false;
 273                 break;
 274
 275               case interactive_once:
 276                 x.interactive = RMI_SOMETIMES;
 277                 x.ignore_missing_files = false;
 278                 prompt_once = true;
 279                 break;
 280
 281               case interactive_always:
 282                 x.interactive = RMI_ALWAYS;
 283                 x.ignore_missing_files = false;
 284                 prompt_once = false;
 285                 break;
 286               }
 287             break;
 288           }
 289
 290         case ONE_FILE_SYSTEM:
 291           x.one_file_system = true;
 292           break;
 293
 294         case NO_PRESERVE_ROOT:
 295           if (! STREQ (argv[optind - 1], "--no-preserve-root"))
 296             die (EXIT_FAILURE, 0,
 297                  _("you may not abbreviate the --no-preserve-root option"));
 298           preserve_root = false;
 299           break;
 300
 301         case PRESERVE_ROOT:
 302           if (optarg)
 303             {
 304               if STREQ (optarg, "all")
 305                 x.preserve_all_root = true;
 306               else
 307                 {
 308                   die (EXIT_FAILURE, 0,
 309                        _("unrecognized --preserve-root argument: %s"),
 310                        quoteaf (optarg));
 311                 }
 312             }
 313           preserve_root = true;
 314           break;
 315
 316         case PRESUME_INPUT_TTY_OPTION:
 317           x.stdin_tty = true;
 318           break;
 319
 320         case 'v':
 321           x.verbose = true;
 322           break;
 323
 324         case_GETOPT_HELP_CHAR;
 325         case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
 326         default:
 327           diagnose_leading_hyphen (argc, argv);
 328           usage (EXIT_FAILURE);
 329         }
 330     }
 331
 332   if (argc <= optind)
 333     {
 334       if (x.ignore_missing_files)
 335         return EXIT_SUCCESS;
 336       else
 337         {
 338           error (0, 0, _("missing operand"));
 339           usage (EXIT_FAILURE);
 340         }
 341     }
 342
 343   if (x.recursive && preserve_root)
 344     {
 345       static struct dev_ino dev_ino_buf;
 346       x.root_dev_ino = get_root_dev_ino (&dev_ino_buf);
 347       if (x.root_dev_ino == NULL)
 348         die (EXIT_FAILURE, errno, _("failed to get attributes of %s"),
 349              quoteaf ("/"));
 350     }
 351
 352   uintmax_t n_files = argc - optind;
 353   char **file =  argv + optind;
 354
 355   if (prompt_once && (x.recursive || 3 < n_files))
 356     {
 357       fprintf (stderr,
 358                (x.recursive
 359                 ? ngettext ("%s: remove %"PRIuMAX" argument recursively? ",
 360                             "%s: remove %"PRIuMAX" arguments recursively? ",
 361                             select_plural (n_files))
 362                 : ngettext ("%s: remove %"PRIuMAX" argument? ",
 363                             "%s: remove %"PRIuMAX" arguments? ",
 364                             select_plural (n_files))),
 365                program_name, n_files);
 366       if (!yesno ())
 367         return EXIT_SUCCESS;
 368     }
 369
 370   enum RM_status status = rm (file, &x);
 371   assert (VALID_STATUS (status));
 372   return status == RM_ERROR ? EXIT_FAILURE : EXIT_SUCCESS;
 373 }