src/rm.c

   1 /* 'rm' file deletion utility for GNU.
   2    Copyright (C) 1988-2016 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 /* 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", no_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   int i;
 109
 110   for (i = 1; i < argc; i++)
 111     {
 112       char const *arg = argv[i];
 113       struct stat st;
 114
 115       if (arg[0] == '-' && arg[1] && lstat (arg, &st) == 0)
 116         {
 117           fprintf (stderr,
 118                    _("Try '%s ./%s' to remove the file %s.\n"),
 119                    argv[0],
 120                    quotearg_n_style (1, shell_escape_quoting_style, arg),
 121                    quoteaf (arg));
 122           break;
 123         }
 124     }
 125 }
 126
 127 void
 128 usage (int status)
 129 {
 130   if (status != EXIT_SUCCESS)
 131     emit_try_help ();
 132   else
 133     {
 134       printf (_("Usage: %s [OPTION]... [FILE]...\n"), program_name);
 135       fputs (_("\
 136 Remove (unlink) the FILE(s).\n\
 137 \n\
 138   -f, --force           ignore nonexistent files and arguments, never prompt\n\
 139   -i                    prompt before every removal\n\
 140 "), stdout);
 141       fputs (_("\
 142   -I                    prompt once before removing more than three files, or\n\
 143                           when removing recursively; less intrusive than -i,\n\
 144                           while still giving protection against most mistakes\n\
 145       --interactive[=WHEN]  prompt according to WHEN: never, once (-I), or\n\
 146                           always (-i); without WHEN, prompt always\n\
 147 "), stdout);
 148       fputs (_("\
 149       --one-file-system  when removing a hierarchy recursively, skip any\n\
 150                           directory that is on a file system different from\n\
 151                           that of the corresponding command line argument\n\
 152 "), stdout);
 153       fputs (_("\
 154       --no-preserve-root  do not treat '/' specially\n\
 155       --preserve-root   do not remove '/' (default)\n\
 156   -r, -R, --recursive   remove directories and their contents recursively\n\
 157   -d, --dir             remove empty directories\n\
 158   -v, --verbose         explain what is being done\n\
 159 "), stdout);
 160       fputs (HELP_OPTION_DESCRIPTION, stdout);
 161       fputs (VERSION_OPTION_DESCRIPTION, stdout);
 162       fputs (_("\
 163 \n\
 164 By default, rm does not remove directories.  Use the --recursive (-r or -R)\n\
 165 option to remove each listed directory, too, along with all of its contents.\n\
 166 "), stdout);
 167       printf (_("\
 168 \n\
 169 To remove a file whose name starts with a '-', for example '-foo',\n\
 170 use one of these commands:\n\
 171   %s -- -foo\n\
 172 \n\
 173   %s ./-foo\n\
 174 "),
 175               program_name, program_name);
 176       fputs (_("\
 177 \n\
 178 Note that if you use rm to remove a file, it might be possible to recover\n\
 179 some of its contents, given sufficient expertise and/or time.  For greater\n\
 180 assurance that the contents are truly unrecoverable, consider using shred.\n\
 181 "), stdout);
 182       emit_ancillary_info (PROGRAM_NAME);
 183     }
 184   exit (status);
 185 }
 186
 187 static void
 188 rm_option_init (struct rm_options *x)
 189 {
 190   x->ignore_missing_files = false;
 191   x->interactive = RMI_SOMETIMES;
 192   x->one_file_system = false;
 193   x->remove_empty_directories = false;
 194   x->recursive = false;
 195   x->root_dev_ino = NULL;
 196   x->stdin_tty = isatty (STDIN_FILENO);
 197   x->verbose = false;
 198
 199   /* Since this program exits immediately after calling 'rm', rm need not
 200      expend unnecessary effort to preserve the initial working directory.  */
 201   x->require_restore_cwd = false;
 202 }
 203
 204 int
 205 main (int argc, char **argv)
 206 {
 207   bool preserve_root = true;
 208   struct rm_options x;
 209   bool prompt_once = false;
 210   int c;
 211
 212   initialize_main (&argc, &argv);
 213   set_program_name (argv[0]);
 214   setlocale (LC_ALL, "");
 215   bindtextdomain (PACKAGE, LOCALEDIR);
 216   textdomain (PACKAGE);
 217
 218   atexit (close_stdin);
 219
 220   rm_option_init (&x);
 221
 222   /* Try to disable the ability to unlink a directory.  */
 223   priv_set_remove_linkdir ();
 224
 225   while ((c = getopt_long (argc, argv, "dfirvIR", long_opts, NULL)) != -1)
 226     {
 227       switch (c)
 228         {
 229         case 'd':
 230           x.remove_empty_directories = true;
 231           break;
 232
 233         case 'f':
 234           x.interactive = RMI_NEVER;
 235           x.ignore_missing_files = true;
 236           prompt_once = false;
 237           break;
 238
 239         case 'i':
 240           x.interactive = RMI_ALWAYS;
 241           x.ignore_missing_files = false;
 242           prompt_once = false;
 243           break;
 244
 245         case 'I':
 246           x.interactive = RMI_SOMETIMES;
 247           x.ignore_missing_files = false;
 248           prompt_once = true;
 249           break;
 250
 251         case 'r':
 252         case 'R':
 253           x.recursive = true;
 254           break;
 255
 256         case INTERACTIVE_OPTION:
 257           {
 258             int i;
 259             if (optarg)
 260               i = XARGMATCH ("--interactive", optarg, interactive_args,
 261                              interactive_types);
 262             else
 263               i = interactive_always;
 264             switch (i)
 265               {
 266               case interactive_never:
 267                 x.interactive = RMI_NEVER;
 268                 prompt_once = false;
 269                 break;
 270
 271               case interactive_once:
 272                 x.interactive = RMI_SOMETIMES;
 273                 x.ignore_missing_files = false;
 274                 prompt_once = true;
 275                 break;
 276
 277               case interactive_always:
 278                 x.interactive = RMI_ALWAYS;
 279                 x.ignore_missing_files = false;
 280                 prompt_once = false;
 281                 break;
 282               }
 283             break;
 284           }
 285
 286         case ONE_FILE_SYSTEM:
 287           x.one_file_system = true;
 288           break;
 289
 290         case NO_PRESERVE_ROOT:
 291           if (! STREQ (argv[optind - 1], "--no-preserve-root"))
 292             die (EXIT_FAILURE, 0,
 293                  _("you may not abbreviate the --no-preserve-root option"));
 294           preserve_root = false;
 295           break;
 296
 297         case PRESERVE_ROOT:
 298           preserve_root = true;
 299           break;
 300
 301         case PRESUME_INPUT_TTY_OPTION:
 302           x.stdin_tty = true;
 303           break;
 304
 305         case 'v':
 306           x.verbose = true;
 307           break;
 308
 309         case_GETOPT_HELP_CHAR;
 310         case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
 311         default:
 312           diagnose_leading_hyphen (argc, argv);
 313           usage (EXIT_FAILURE);
 314         }
 315     }
 316
 317   if (argc <= optind)
 318     {
 319       if (x.ignore_missing_files)
 320         return EXIT_SUCCESS;
 321       else
 322         {
 323           error (0, 0, _("missing operand"));
 324           usage (EXIT_FAILURE);
 325         }
 326     }
 327
 328   if (x.recursive && preserve_root)
 329     {
 330       static struct dev_ino dev_ino_buf;
 331       x.root_dev_ino = get_root_dev_ino (&dev_ino_buf);
 332       if (x.root_dev_ino == NULL)
 333         die (EXIT_FAILURE, errno, _("failed to get attributes of %s"),
 334              quoteaf ("/"));
 335     }
 336
 337   uintmax_t n_files = argc - optind;
 338   char **file =  argv + optind;
 339
 340   if (prompt_once && (x.recursive || 3 < n_files))
 341     {
 342       fprintf (stderr,
 343                (x.recursive
 344                 ? ngettext ("%s: remove %"PRIuMAX" argument recursively? ",
 345                             "%s: remove %"PRIuMAX" arguments recursively? ",
 346                             select_plural (n_files))
 347                 : ngettext ("%s: remove %"PRIuMAX" argument? ",
 348                             "%s: remove %"PRIuMAX" arguments? ",
 349                             select_plural (n_files))),
 350                program_name, n_files);
 351       if (!yesno ())
 352         return EXIT_SUCCESS;
 353     }
 354
 355   enum RM_status status = rm (file, &x);
 356   assert (VALID_STATUS (status));
 357   return status == RM_ERROR ? EXIT_FAILURE : EXIT_SUCCESS;
 358 }