src/rm.c

   1 /* `rm' file deletion utility for GNU.
   2    Copyright (C) 88, 90, 91, 1994-2003 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 2, or (at your option)
   7    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, write to the Free Software Foundation,
  16    Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  17
  18 /* Written by Paul Rubin, David MacKenzie, and Richard Stallman.
  19    Reworked to use chdir and avoid recursion by Jim Meyering.  */
  20
  21 /* Implementation overview:
  22
  23    In the `usual' case, RM saves no state for directories it is processing.
  24    When a removal fails (either due to an error or to an interactive `no'
  25    reply), the failure is noted (see description of `ht' in remove.c's
  26    remove_cwd_entries function) so that when/if the containing directory
  27    is reopened, RM doesn't try to remove the entry again.
  28
  29    RM may delete arbitrarily deep hierarchies -- even ones in which file
  30    names (from root to leaf) are longer than the system-imposed maximum.
  31    It does this by using chdir to change to each directory in turn before
  32    removing the entries in that directory.
  33
  34    RM detects directory cycles lazily.  See lib/cycle-check.c.
  35
  36    RM is careful to avoid forming full file names whenever possible.
  37    A full file name is formed only when it is about to be used -- e.g.
  38    in a diagnostic or in an interactive-mode prompt.
  39
  40    RM minimizes the number of lstat system calls it makes.  On systems
  41    that have valid d_type data in directory entries, RM makes only one
  42    lstat call per command line argument -- regardless of the depth of
  43    the hierarchy.  */
  44
  45 #include <config.h>
  46 #include <stdio.h>
  47 #include <getopt.h>
  48 #include <sys/types.h>
  49 #include <assert.h>
  50
  51 #include "system.h"
  52 #include "dirname.h"
  53 #include "error.h"
  54 #include "quote.h"
  55 #include "remove.h"
  56 #include "root-dev-ino.h"
  57 #include "save-cwd.h"
  58
  59 /* The official name of this program (e.g., no `g' prefix).  */
  60 #define PROGRAM_NAME "rm"
  61
  62 #define AUTHORS \
  63   "Paul Rubin", "David MacKenzie, Richard Stallman", "Jim Meyering"
  64
  65 /* Name this program was run with.  */
  66 char *program_name;
  67
  68 /* For long options that have no equivalent short option, use a
  69    non-character as a pseudo short option, starting with CHAR_MAX + 1.  */
  70 enum
  71 {
  72   NO_PRESERVE_ROOT = CHAR_MAX + 1,
  73   PRESERVE_ROOT,
  74   PRESUME_INPUT_TTY_OPTION
  75 };
  76
  77 static struct option const long_opts[] =
  78 {
  79   {"directory", no_argument, NULL, 'd'},
  80   {"force", no_argument, NULL, 'f'},
  81   {"interactive", no_argument, NULL, 'i'},
  82
  83   {"no-preserve-root", no_argument, 0, NO_PRESERVE_ROOT},
  84   {"preserve-root", no_argument, 0, PRESERVE_ROOT},
  85
  86   /* This is solely for testing.  Do not document.  */
  87   /* It is relatively difficult to ensure that there is a tty on stdin.
  88      Since rm acts differently depending on that, without this option,
  89      it'd be harder to test the parts of rm that depend on that setting.  */
  90   {"presume-input-tty", no_argument, NULL, PRESUME_INPUT_TTY_OPTION},
  91
  92   {"recursive", no_argument, NULL, 'r'},
  93   {"verbose", no_argument, NULL, 'v'},
  94   {GETOPT_HELP_OPTION_DECL},
  95   {GETOPT_VERSION_OPTION_DECL},
  96   {NULL, 0, NULL, 0}
  97 };
  98
  99 void
 100 usage (int status)
 101 {
 102   if (status != 0)
 103     fprintf (stderr, _("Try `%s --help' for more information.\n"),
 104              program_name);
 105   else
 106     {
 107       char *base = base_name (program_name);
 108       printf (_("Usage: %s [OPTION]... FILE...\n"), program_name);
 109       fputs (_("\
 110 Remove (unlink) the FILE(s).\n\
 111 \n\
 112   -d, --directory       unlink FILE, even if it is a non-empty directory\n\
 113                           (super-user only; this works only if your system\n\
 114                            supports `unlink' for nonempty directories)\n\
 115   -f, --force           ignore nonexistent files, never prompt\n\
 116   -i, --interactive     prompt before any removal\n\
 117 "), stdout);
 118       fputs (_("\
 119       --no-preserve-root do not treat `/' specially (the default)\n\
 120       --preserve-root   fail to operate recursively on `/'\n\
 121   -r, -R, --recursive   remove the contents of directories recursively\n\
 122   -v, --verbose         explain what is being done\n\
 123 "), stdout);
 124       fputs (HELP_OPTION_DESCRIPTION, stdout);
 125       fputs (VERSION_OPTION_DESCRIPTION, stdout);
 126       printf (_("\
 127 \n\
 128 To remove a file whose name starts with a `-', for example `-foo',\n\
 129 use one of these commands:\n\
 130   %s -- -foo\n\
 131 \n\
 132   %s ./-foo\n\
 133 "),
 134               base, base);
 135       fputs (_("\
 136 \n\
 137 Note that if you use rm to remove a file, it is usually possible to recover\n\
 138 the contents of that file.  If you want more assurance that the contents are\n\
 139 truly unrecoverable, consider using shred.\n\
 140 "), stdout);
 141       printf (_("\nReport bugs to <%s>.\n"), PACKAGE_BUGREPORT);
 142     }
 143   exit (status);
 144 }
 145
 146 static void
 147 rm_option_init (struct rm_options *x)
 148 {
 149   x->unlink_dirs = 0;
 150   x->ignore_missing_files = 0;
 151   x->interactive = 0;
 152   x->recursive = 0;
 153   x->root_dev_ino = NULL;
 154   x->stdin_tty = isatty (STDIN_FILENO);
 155   x->verbose = 0;
 156 }
 157
 158 int
 159 main (int argc, char **argv)
 160 {
 161   bool preserve_root = false;
 162   struct rm_options x;
 163   int fail = 0;
 164   int c;
 165
 166   initialize_main (&argc, &argv);
 167   program_name = argv[0];
 168   setlocale (LC_ALL, "");
 169   bindtextdomain (PACKAGE, LOCALEDIR);
 170   textdomain (PACKAGE);
 171
 172   atexit (close_stdout);
 173
 174   rm_option_init (&x);
 175
 176   while ((c = getopt_long (argc, argv, "dfirvR", long_opts, NULL)) != -1)
 177     {
 178       switch (c)
 179         {
 180         case 0:         /* Long option.  */
 181           break;
 182
 183         case 'd':
 184           x.unlink_dirs = 1;
 185           break;
 186
 187         case 'f':
 188           x.interactive = 0;
 189           x.ignore_missing_files = 1;
 190           break;
 191
 192         case 'i':
 193           x.interactive = 1;
 194           x.ignore_missing_files = 0;
 195           break;
 196
 197         case 'r':
 198         case 'R':
 199           x.recursive = 1;
 200           break;
 201
 202         case NO_PRESERVE_ROOT:
 203           preserve_root = false;
 204           break;
 205
 206         case PRESERVE_ROOT:
 207           preserve_root = true;
 208           break;
 209
 210         case PRESUME_INPUT_TTY_OPTION:
 211           x.stdin_tty = 1;
 212           break;
 213
 214         case 'v':
 215           x.verbose = 1;
 216           break;
 217
 218         case_GETOPT_HELP_CHAR;
 219         case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
 220         default:
 221           usage (EXIT_FAILURE);
 222         }
 223     }
 224
 225   if (argc <= optind)
 226     {
 227       if (x.ignore_missing_files)
 228         exit (EXIT_SUCCESS);
 229       else
 230         {
 231           error (0, 0, _("too few arguments"));
 232           usage (EXIT_FAILURE);
 233         }
 234     }
 235
 236   if (x.recursive && preserve_root)
 237     {
 238       static struct dev_ino dev_ino_buf;
 239       x.root_dev_ino = get_root_dev_ino (&dev_ino_buf);
 240       if (x.root_dev_ino == NULL)
 241         error (EXIT_FAILURE, errno, _("failed to get attributes of %s"),
 242                quote ("/"));
 243     }
 244
 245   {
 246     size_t n_files = argc - optind;
 247     char const *const *file = (char const *const *) argv + optind;
 248
 249     enum RM_status status = rm (n_files, file, &x);
 250     assert (VALID_STATUS (status));
 251     if (status == RM_ERROR)
 252       fail = 1;
 253   }
 254
 255   exit (fail);
 256 }