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 "error.h"
  30 #include "remove.h"
  31 #include "root-dev-ino.h"
  32 #include "yesno.h"
  33 #include "priv-set.h"
  34
  35 /* The official name of this program (e.g., no 'g' prefix).  */
  36 #define PROGRAM_NAME "rm"
  37
  38 #define AUTHORS \
  39   proper_name ("Paul Rubin"), \
  40   proper_name ("David MacKenzie"), \
  41   proper_name ("Richard M. Stallman"), \
  42   proper_name ("Jim Meyering")
  43
  44 /* For long options that have no equivalent short option, use a
  45    non-character as a pseudo short option, starting with CHAR_MAX + 1.  */
  46 enum
  47 {
  48   INTERACTIVE_OPTION = CHAR_MAX + 1,
  49   ONE_FILE_SYSTEM,
  50   NO_PRESERVE_ROOT,
  51   PRESERVE_ROOT,
  52   PRESUME_INPUT_TTY_OPTION
  53 };
  54
  55 enum interactive_type
  56   {
  57     interactive_never,          /* 0: no option or --interactive=never */
  58     interactive_once,           /* 1: -I or --interactive=once */
  59     interactive_always          /* 2: default, -i or --interactive=always */
  60   };
  61
  62 static struct option const long_opts[] =
  63 {
  64   {"force", no_argument, NULL, 'f'},
  65   {"interactive", optional_argument, NULL, INTERACTIVE_OPTION},
  66
  67   {"one-file-system", no_argument, NULL, ONE_FILE_SYSTEM},
  68   {"no-preserve-root", no_argument, NULL, NO_PRESERVE_ROOT},
  69   {"preserve-root", no_argument, NULL, PRESERVE_ROOT},
  70
  71   /* This is solely for testing.  Do not document.  */
  72   /* It is relatively difficult to ensure that there is a tty on stdin.
  73      Since rm acts differently depending on that, without this option,
  74      it'd be harder to test the parts of rm that depend on that setting.  */
  75   {"-presume-input-tty", no_argument, NULL, PRESUME_INPUT_TTY_OPTION},
  76
  77   {"recursive", no_argument, NULL, 'r'},
  78   {"dir", no_argument, NULL, 'd'},
  79   {"verbose", no_argument, NULL, 'v'},
  80   {GETOPT_HELP_OPTION_DECL},
  81   {GETOPT_VERSION_OPTION_DECL},
  82   {NULL, 0, NULL, 0}
  83 };
  84
  85 static char const *const interactive_args[] =
  86 {
  87   "never", "no", "none",
  88   "once",
  89   "always", "yes", NULL
  90 };
  91 static enum interactive_type const interactive_types[] =
  92 {
  93   interactive_never, interactive_never, interactive_never,
  94   interactive_once,
  95   interactive_always, interactive_always
  96 };
  97 ARGMATCH_VERIFY (interactive_args, interactive_types);
  98
  99 /* Advise the user about invalid usages like "rm -foo" if the file
 100    "-foo" exists, assuming ARGC and ARGV are as with 'main'.  */
 101
 102 static void
 103 diagnose_leading_hyphen (int argc, char **argv)
 104 {
 105   /* OPTIND is unreliable, so iterate through the arguments looking
 106      for a file name that looks like an option.  */
 107   int i;
 108
 109   for (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   do not remove '/' (default)\n\
 155   -r, -R, --recursive   remove directories and their contents recursively\n\
 156   -d, --dir             remove empty directories\n\
 157   -v, --verbose         explain what is being done\n\
 158 "), stdout);
 159       fputs (HELP_OPTION_DESCRIPTION, stdout);
 160       fputs (VERSION_OPTION_DESCRIPTION, stdout);
 161       fputs (_("\
 162 \n\
 163 By default, rm does not remove directories.  Use the --recursive (-r or -R)\n\
 164 option to remove each listed directory, too, along with all of its contents.\n\
 165 "), stdout);
 166       printf (_("\
 167 \n\
 168 To remove a file whose name starts with a '-', for example '-foo',\n\
 169 use one of these commands:\n\
 170   %s -- -foo\n\
 171 \n\
 172   %s ./-foo\n\
 173 "),
 174               program_name, program_name);
 175       fputs (_("\
 176 \n\
 177 Note that if you use rm to remove a file, it might be possible to recover\n\
 178 some of its contents, given sufficient expertise and/or time.  For greater\n\
 179 assurance that the contents are truly unrecoverable, consider using shred.\n\
 180 "), stdout);
 181       emit_ancillary_info (PROGRAM_NAME);
 182     }
 183   exit (status);
 184 }
 185
 186 static void
 187 rm_option_init (struct rm_options *x)
 188 {
 189   x->ignore_missing_files = false;
 190   x->interactive = RMI_SOMETIMES;
 191   x->one_file_system = false;
 192   x->remove_empty_directories = false;
 193   x->recursive = false;
 194   x->root_dev_ino = NULL;
 195   x->stdin_tty = isatty (STDIN_FILENO);
 196   x->verbose = false;
 197
 198   /* Since this program exits immediately after calling 'rm', rm need not
 199      expend unnecessary effort to preserve the initial working directory.  */
 200   x->require_restore_cwd = false;
 201 }
 202
 203 int
 204 main (int argc, char **argv)
 205 {
 206   bool preserve_root = true;
 207   struct rm_options x;
 208   bool prompt_once = false;
 209   int c;
 210
 211   initialize_main (&argc, &argv);
 212   set_program_name (argv[0]);
 213   setlocale (LC_ALL, "");
 214   bindtextdomain (PACKAGE, LOCALEDIR);
 215   textdomain (PACKAGE);
 216
 217   atexit (close_stdin);
 218
 219   rm_option_init (&x);
 220
 221   /* Try to disable the ability to unlink a directory.  */
 222   priv_set_remove_linkdir ();
 223
 224   while ((c = getopt_long (argc, argv, "dfirvIR", long_opts, NULL)) != -1)
 225     {
 226       switch (c)
 227         {
 228         case 'd':
 229           x.remove_empty_directories = true;
 230           break;
 231
 232         case 'f':
 233           x.interactive = RMI_NEVER;
 234           x.ignore_missing_files = true;
 235           prompt_once = false;
 236           break;
 237
 238         case 'i':
 239           x.interactive = RMI_ALWAYS;
 240           x.ignore_missing_files = false;
 241           prompt_once = false;
 242           break;
 243
 244         case 'I':
 245           x.interactive = RMI_SOMETIMES;
 246           x.ignore_missing_files = false;
 247           prompt_once = true;
 248           break;
 249
 250         case 'r':
 251         case 'R':
 252           x.recursive = true;
 253           break;
 254
 255         case INTERACTIVE_OPTION:
 256           {
 257             int i;
 258             if (optarg)
 259               i = XARGMATCH ("--interactive", optarg, interactive_args,
 260                              interactive_types);
 261             else
 262               i = interactive_always;
 263             switch (i)
 264               {
 265               case interactive_never:
 266                 x.interactive = RMI_NEVER;
 267                 prompt_once = false;
 268                 break;
 269
 270               case interactive_once:
 271                 x.interactive = RMI_SOMETIMES;
 272                 x.ignore_missing_files = false;
 273                 prompt_once = true;
 274                 break;
 275
 276               case interactive_always:
 277                 x.interactive = RMI_ALWAYS;
 278                 x.ignore_missing_files = false;
 279                 prompt_once = false;
 280                 break;
 281               }
 282             break;
 283           }
 284
 285         case ONE_FILE_SYSTEM:
 286           x.one_file_system = true;
 287           break;
 288
 289         case NO_PRESERVE_ROOT:
 290           preserve_root = false;
 291           break;
 292
 293         case PRESERVE_ROOT:
 294           preserve_root = true;
 295           break;
 296
 297         case PRESUME_INPUT_TTY_OPTION:
 298           x.stdin_tty = true;
 299           break;
 300
 301         case 'v':
 302           x.verbose = true;
 303           break;
 304
 305         case_GETOPT_HELP_CHAR;
 306         case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
 307         default:
 308           diagnose_leading_hyphen (argc, argv);
 309           usage (EXIT_FAILURE);
 310         }
 311     }
 312
 313   if (argc <= optind)
 314     {
 315       if (x.ignore_missing_files)
 316         return EXIT_SUCCESS;
 317       else
 318         {
 319           error (0, 0, _("missing operand"));
 320           usage (EXIT_FAILURE);
 321         }
 322     }
 323
 324   if (x.recursive && preserve_root)
 325     {
 326       static struct dev_ino dev_ino_buf;
 327       x.root_dev_ino = get_root_dev_ino (&dev_ino_buf);
 328       if (x.root_dev_ino == NULL)
 329         error (EXIT_FAILURE, errno, _("failed to get attributes of %s"),
 330                quoteaf ("/"));
 331     }
 332
 333   uintmax_t n_files = argc - optind;
 334   char **file =  argv + optind;
 335
 336   if (prompt_once && (x.recursive || 3 < n_files))
 337     {
 338       fprintf (stderr,
 339                (x.recursive
 340                 ? ngettext ("%s: remove %"PRIuMAX" argument recursively? ",
 341                             "%s: remove %"PRIuMAX" arguments recursively? ",
 342                             select_plural (n_files))
 343                 : ngettext ("%s: remove %"PRIuMAX" argument? ",
 344                             "%s: remove %"PRIuMAX" arguments? ",
 345                             select_plural (n_files))),
 346                program_name, n_files);
 347       if (!yesno ())
 348         return EXIT_SUCCESS;
 349     }
 350
 351   enum RM_status status = rm (file, &x);
 352   assert (VALID_STATUS (status));
 353   return status == RM_ERROR ? EXIT_FAILURE : EXIT_SUCCESS;
 354 }