rm.c (GNU coreutils 8.26)

gistfile1.txt

/* 'rm' file deletion utility for GNU.
   Copyright (C) 1988-2016 Free Software Foundation, Inc.

   This program is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation, either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

/* Initially written by Paul Rubin, David MacKenzie, and Richard Stallman.
   Reworked to use chdir and avoid recursion, and later, rewritten
   once again, to use fts, by Jim Meyering.  */

#include <config.h>
#include <stdio.h>
#include <getopt.h>
#include <sys/types.h>
#include <assert.h>

#include "system.h"
#include "argmatch.h"
#include "die.h"
#include "error.h"
#include "remove.h"
#include "root-dev-ino.h"
#include "yesno.h"
#include "priv-set.h"

/* The official name of this program (e.g., no 'g' prefix).  */
#define PROGRAM_NAME "rm"

#define AUTHORS \
  proper_name ("Paul Rubin"), \
  proper_name ("David MacKenzie"), \
  proper_name ("Richard M. Stallman"), \
  proper_name ("Jim Meyering")

/* For long options that have no equivalent short option, use a
   non-character as a pseudo short option, starting with CHAR_MAX + 1.  */
enum
{
  INTERACTIVE_OPTION = CHAR_MAX + 1,
  ONE_FILE_SYSTEM,
  NO_PRESERVE_ROOT,
  PRESERVE_ROOT,
  PRESUME_INPUT_TTY_OPTION
};

enum interactive_type
  {
    interactive_never,		/* 0: no option or --interactive=never */
    interactive_once,		/* 1: -I or --interactive=once */
    interactive_always		/* 2: default, -i or --interactive=always */
  };

static struct option const long_opts[] =
{
  {"force", no_argument, NULL, 'f'},
  {"interactive", optional_argument, NULL, INTERACTIVE_OPTION},

  {"one-file-system", no_argument, NULL, ONE_FILE_SYSTEM},
  {"no-preserve-root", no_argument, NULL, NO_PRESERVE_ROOT},
  {"preserve-root", no_argument, NULL, PRESERVE_ROOT},

  /* This is solely for testing.  Do not document.  */
  /* It is relatively difficult to ensure that there is a tty on stdin.
     Since rm acts differently depending on that, without this option,
     it'd be harder to test the parts of rm that depend on that setting.  */
  {"-presume-input-tty", no_argument, NULL, PRESUME_INPUT_TTY_OPTION},

  {"recursive", no_argument, NULL, 'r'},
  {"dir", no_argument, NULL, 'd'},
  {"verbose", no_argument, NULL, 'v'},
  {GETOPT_HELP_OPTION_DECL},
  {GETOPT_VERSION_OPTION_DECL},
  {NULL, 0, NULL, 0}
};

static char const *const interactive_args[] =
{
  "never", "no", "none",
  "once",
  "always", "yes", NULL
};
static enum interactive_type const interactive_types[] =
{
  interactive_never, interactive_never, interactive_never,
  interactive_once,
  interactive_always, interactive_always
};
ARGMATCH_VERIFY (interactive_args, interactive_types);

/* Advise the user about invalid usages like "rm -foo" if the file
   "-foo" exists, assuming ARGC and ARGV are as with 'main'.  */

static void
diagnose_leading_hyphen (int argc, char **argv)
{
  /* OPTIND is unreliable, so iterate through the arguments looking
     for a file name that looks like an option.  */
  int i;

  for (i = 1; i < argc; i++)
    {
      char const *arg = argv[i];
      struct stat st;

      if (arg[0] == '-' && arg[1] && lstat (arg, &st) == 0)
        {
          fprintf (stderr,
                   _("Try '%s ./%s' to remove the file %s.\n"),
                   argv[0],
                   quotearg_n_style (1, shell_escape_quoting_style, arg),
                   quoteaf (arg));
          break;
        }
    }
}

void
usage (int status)
{
  if (status != EXIT_SUCCESS)
    emit_try_help ();
  else
    {
      printf (_("Usage: %s [OPTION]... [FILE]...\n"), program_name);
      fputs (_("\
Remove (unlink) the FILE(s).\n\
\n\
  -f, --force           ignore nonexistent files and arguments, never prompt\n\
  -i                    prompt before every removal\n\
"), stdout);
      fputs (_("\
  -I                    prompt once before removing more than three files, or\n\
                          when removing recursively; less intrusive than -i,\n\
                          while still giving protection against most mistakes\n\
      --interactive[=WHEN]  prompt according to WHEN: never, once (-I), or\n\
                          always (-i); without WHEN, prompt always\n\
"), stdout);
      fputs (_("\
      --one-file-system  when removing a hierarchy recursively, skip any\n\
                          directory that is on a file system different from\n\
                          that of the corresponding command line argument\n\
"), stdout);
      fputs (_("\
      --no-preserve-root  do not treat '/' specially\n\
      --preserve-root   do not remove '/' (default)\n\
  -r, -R, --recursive   remove directories and their contents recursively\n\
  -d, --dir             remove empty directories\n\
  -v, --verbose         explain what is being done\n\
"), stdout);
      fputs (HELP_OPTION_DESCRIPTION, stdout);
      fputs (VERSION_OPTION_DESCRIPTION, stdout);
      fputs (_("\
\n\
By default, rm does not remove directories.  Use the --recursive (-r or -R)\n\
option to remove each listed directory, too, along with all of its contents.\n\
"), stdout);
      printf (_("\
\n\
To remove a file whose name starts with a '-', for example '-foo',\n\
use one of these commands:\n\
  %s -- -foo\n\
\n\
  %s ./-foo\n\
"),
              program_name, program_name);
      fputs (_("\
\n\
Note that if you use rm to remove a file, it might be possible to recover\n\
some of its contents, given sufficient expertise and/or time.  For greater\n\
assurance that the contents are truly unrecoverable, consider using shred.\n\
"), stdout);
      emit_ancillary_info (PROGRAM_NAME);
    }
  exit (status);
}

static void
rm_option_init (struct rm_options *x)
{
  x->ignore_missing_files = false;
  x->interactive = RMI_SOMETIMES;
  x->one_file_system = false;
  x->remove_empty_directories = false;
  x->recursive = false;
  x->root_dev_ino = NULL;
  x->stdin_tty = isatty (STDIN_FILENO);
  x->verbose = false;

  /* Since this program exits immediately after calling 'rm', rm need not
     expend unnecessary effort to preserve the initial working directory.  */
  x->require_restore_cwd = false;
}

int
main (int argc, char **argv)
{
  bool preserve_root = true;
  struct rm_options x;
  bool prompt_once = false;
  int c;

  initialize_main (&argc, &argv);
  set_program_name (argv[0]);
  setlocale (LC_ALL, "");
  bindtextdomain (PACKAGE, LOCALEDIR);
  textdomain (PACKAGE);

  atexit (close_stdin);

  rm_option_init (&x);

  /* Try to disable the ability to unlink a directory.  */
  priv_set_remove_linkdir ();

  while ((c = getopt_long (argc, argv, "dfirvIR", long_opts, NULL)) != -1)
    {
      switch (c)
        {
        case 'd':
          x.remove_empty_directories = true;
          break;

        case 'f':
          x.interactive = RMI_NEVER;
          x.ignore_missing_files = true;
          prompt_once = false;
          break;

        case 'i':
          x.interactive = RMI_ALWAYS;
          x.ignore_missing_files = false;
          prompt_once = false;
          break;

        case 'I':
          x.interactive = RMI_SOMETIMES;
          x.ignore_missing_files = false;
          prompt_once = true;
          break;

        case 'r':
        case 'R':
          x.recursive = true;
          break;

        case INTERACTIVE_OPTION:
          {
            int i;
            if (optarg)
              i = XARGMATCH ("--interactive", optarg, interactive_args,
                             interactive_types);
            else
              i = interactive_always;
            switch (i)
              {
              case interactive_never:
                x.interactive = RMI_NEVER;
                prompt_once = false;
                break;

              case interactive_once:
                x.interactive = RMI_SOMETIMES;
                x.ignore_missing_files = false;
                prompt_once = true;
                break;

              case interactive_always:
                x.interactive = RMI_ALWAYS;
                x.ignore_missing_files = false;
                prompt_once = false;
                break;
              }
            break;
          }

        case ONE_FILE_SYSTEM:
          x.one_file_system = true;
          break;

        case NO_PRESERVE_ROOT:
          if (! STREQ (argv[optind - 1], "--no-preserve-root"))
            die (EXIT_FAILURE, 0,
                 _("you may not abbreviate the --no-preserve-root option"));
          preserve_root = false;
          break;

        case PRESERVE_ROOT:
          preserve_root = true;
          break;

        case PRESUME_INPUT_TTY_OPTION:
          x.stdin_tty = true;
          break;

        case 'v':
          x.verbose = true;
          break;

        case_GETOPT_HELP_CHAR;
        case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
        default:
          diagnose_leading_hyphen (argc, argv);
          usage (EXIT_FAILURE);
        }
    }

  if (argc <= optind)
    {
      if (x.ignore_missing_files)
        return EXIT_SUCCESS;
      else
        {
          error (0, 0, _("missing operand"));
          usage (EXIT_FAILURE);
        }
    }

  if (x.recursive && preserve_root)
    {
      static struct dev_ino dev_ino_buf;
      x.root_dev_ino = get_root_dev_ino (&dev_ino_buf);
      if (x.root_dev_ino == NULL)
        die (EXIT_FAILURE, errno, _("failed to get attributes of %s"),
             quoteaf ("/"));
    }

  uintmax_t n_files = argc - optind;
  char **file =  argv + optind;

  if (prompt_once && (x.recursive || 3 < n_files))
    {
      fprintf (stderr,
               (x.recursive
                ? ngettext ("%s: remove %"PRIuMAX" argument recursively? ",
                            "%s: remove %"PRIuMAX" arguments recursively? ",
                            select_plural (n_files))
                : ngettext ("%s: remove %"PRIuMAX" argument? ",
                            "%s: remove %"PRIuMAX" arguments? ",
                            select_plural (n_files))),
               program_name, n_files);
      if (!yesno ())
        return EXIT_SUCCESS;
    }

  enum RM_status status = rm (file, &x);
  assert (VALID_STATUS (status));
  return status == RM_ERROR ? EXIT_FAILURE : EXIT_SUCCESS;
}

struct rm_options
{
  /* If true, ignore nonexistent files.  */
  bool ignore_missing_files;

  /* If true, query the user about whether to remove each file.  */
  enum rm_interactive interactive;

  // FIXME: remove
  /* If true, do not traverse into (or remove) any directory that is
     on a file system (i.e., that has a different device number) other
     than that of the corresponding command line argument.  Note that
     even without this option, rm will fail in the end, due to its
     probable inability to remove the mount point.  But there, the
     diagnostic comes too late -- after removing all contents.  */
  bool one_file_system;

  /* If true, recursively remove directories.  */
  bool recursive;

  /* If true, remove empty directories.  */
  bool remove_empty_directories;

  /* Pointer to the device and inode numbers of '/', when --recursive
     and preserving '/'.  Otherwise NULL.  */
  struct dev_ino *root_dev_ino;

  /* If nonzero, stdin is a tty.  */
  bool stdin_tty;

  /* If true, display the name of each file removed.  */
  bool verbose;

  /* If true, treat the failure by the rm function to restore the
     current working directory as a fatal error.  I.e., if this field
     is true and the rm function cannot restore cwd, it must exit with
     a nonzero status.  Some applications require that the rm function
     restore cwd (e.g., mv) and some others do not (e.g., rm,
     in many cases).  */
  bool require_restore_cwd;
};