src/rm.c

   1 /* 'rm' file deletion utility for GNU.
   2    Copyright (C) 1988-2012 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 "quote.h"
  31 #include "quotearg.h"
  32 #include "remove.h"
  33 #include "root-dev-ino.h"
  34 #include "yesno.h"
  35 #include "priv-set.h"
  36
  37 /* The official name of this program (e.g., no 'g' prefix).  */
  38 #define PROGRAM_NAME "rm"
  39
  40 #define AUTHORS \
  41   proper_name ("Paul Rubin"), \
  42   proper_name ("David MacKenzie"), \
  43   proper_name ("Richard M. Stallman"), \
  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   INTERACTIVE_OPTION = CHAR_MAX + 1,
  51   ONE_FILE_SYSTEM,
  52   NO_PRESERVE_ROOT,
  53   PRESERVE_ROOT,
  54   PRESUME_INPUT_TTY_OPTION
  55 };
  56
  57 enum interactive_type
  58   {
  59     interactive_never,          /* 0: no option or --interactive=never */
  60     interactive_once,           /* 1: -I or --interactive=once */
  61     interactive_always          /* 2: default, -i or --interactive=always */
  62   };
  63
  64 static struct option const long_opts[] =
  65 {
  66   {"force", no_argument, NULL, 'f'},
  67   {"interactive", optional_argument, NULL, INTERACTIVE_OPTION},
  68
  69   {"one-file-system", no_argument, NULL, ONE_FILE_SYSTEM},
  70   {"no-preserve-root", no_argument, NULL, NO_PRESERVE_ROOT},
  71   {"preserve-root", no_argument, NULL, PRESERVE_ROOT},
  72
  73   /* This is solely for testing.  Do not document.  */
  74   /* It is relatively difficult to ensure that there is a tty on stdin.
  75      Since rm acts differently depending on that, without this option,
  76      it'd be harder to test the parts of rm that depend on that setting.  */
  77   {"-presume-input-tty", no_argument, NULL, PRESUME_INPUT_TTY_OPTION},
  78
  79   {"recursive", no_argument, NULL, 'r'},
  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_quoting_style, arg),
 121                    quote (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   -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 ();
 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->recursive = false;
 193   x->root_dev_ino = NULL;
 194   x->stdin_tty = isatty (STDIN_FILENO);
 195   x->verbose = false;
 196
 197   /* Since this program exits immediately after calling 'rm', rm need not
 198      expend unnecessary effort to preserve the initial working directory.  */
 199   x->require_restore_cwd = false;
 200 }
 201
 202 int
 203 main (int argc, char **argv)
 204 {
 205   bool preserve_root = true;
 206   struct rm_options x;
 207   bool prompt_once = false;
 208   int c;
 209
 210   initialize_main (&argc, &argv);
 211   set_program_name (argv[0]);
 212   setlocale (LC_ALL, "");
 213   bindtextdomain (PACKAGE, LOCALEDIR);
 214   textdomain (PACKAGE);
 215
 216   atexit (close_stdin);
 217
 218   rm_option_init (&x);
 219
 220   /* Try to disable the ability to unlink a directory.  */
 221   priv_set_remove_linkdir ();
 222
 223   while ((c = getopt_long (argc, argv, "firvIR", long_opts, NULL)) != -1)
 224     {
 225       switch (c)
 226         {
 227         case 'f':
 228           x.interactive = RMI_NEVER;
 229           x.ignore_missing_files = true;
 230           prompt_once = false;
 231           break;
 232
 233         case 'i':
 234           x.interactive = RMI_ALWAYS;
 235           x.ignore_missing_files = false;
 236           prompt_once = false;
 237           break;
 238
 239         case 'I':
 240           x.interactive = RMI_NEVER;
 241           x.ignore_missing_files = false;
 242           prompt_once = true;
 243           break;
 244
 245         case 'r':
 246         case 'R':
 247           x.recursive = true;
 248           break;
 249
 250         case INTERACTIVE_OPTION:
 251           {
 252             int i;
 253             if (optarg)
 254               i = XARGMATCH ("--interactive", optarg, interactive_args,
 255                              interactive_types);
 256             else
 257               i = interactive_always;
 258             switch (i)
 259               {
 260               case interactive_never:
 261                 x.interactive = RMI_NEVER;
 262                 prompt_once = false;
 263                 break;
 264
 265               case interactive_once:
 266                 x.interactive = RMI_SOMETIMES;
 267                 x.ignore_missing_files = false;
 268                 prompt_once = true;
 269                 break;
 270
 271               case interactive_always:
 272                 x.interactive = RMI_ALWAYS;
 273                 x.ignore_missing_files = false;
 274                 prompt_once = false;
 275                 break;
 276               }
 277             break;
 278           }
 279
 280         case ONE_FILE_SYSTEM:
 281           x.one_file_system = true;
 282           break;
 283
 284         case NO_PRESERVE_ROOT:
 285           preserve_root = false;
 286           break;
 287
 288         case PRESERVE_ROOT:
 289           preserve_root = true;
 290           break;
 291
 292         case PRESUME_INPUT_TTY_OPTION:
 293           x.stdin_tty = true;
 294           break;
 295
 296         case 'v':
 297           x.verbose = true;
 298           break;
 299
 300         case_GETOPT_HELP_CHAR;
 301         case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
 302         default:
 303           diagnose_leading_hyphen (argc, argv);
 304           usage (EXIT_FAILURE);
 305         }
 306     }
 307
 308   if (argc <= optind)
 309     {
 310       if (x.ignore_missing_files)
 311         exit (EXIT_SUCCESS);
 312       else
 313         {
 314           error (0, 0, _("missing operand"));
 315           usage (EXIT_FAILURE);
 316         }
 317     }
 318
 319   if (x.recursive && preserve_root)
 320     {
 321       static struct dev_ino dev_ino_buf;
 322       x.root_dev_ino = get_root_dev_ino (&dev_ino_buf);
 323       if (x.root_dev_ino == NULL)
 324         error (EXIT_FAILURE, errno, _("failed to get attributes of %s"),
 325                quote ("/"));
 326     }
 327
 328   size_t n_files = argc - optind;
 329   char **file =  argv + optind;
 330
 331   if (prompt_once && (x.recursive || 3 < n_files))
 332     {
 333       fprintf (stderr,
 334                (x.recursive
 335                 ? _("%s: remove all arguments recursively? ")
 336                 : _("%s: remove all arguments? ")),
 337                program_name);
 338       if (!yesno ())
 339         exit (EXIT_SUCCESS);
 340     }
 341
 342   enum RM_status status = rm (file, &x);
 343   assert (VALID_STATUS (status));
 344   exit (status == RM_ERROR ? EXIT_FAILURE : EXIT_SUCCESS);
 345 }