summaryrefslogtreecommitdiff
path: root/src/chmod.c
blob: 852fe47e6327eef763e54e0981af90eb649bd29b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
/* chmod -- change permission modes of files
   Copyright (C) 89, 90, 91, 1995-2001 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 2, 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, write to the Free Software Foundation,
   Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */

/* Written by David MacKenzie <djm@gnu.ai.mit.edu> */

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

#include "system.h"
#include "error.h"
#include "filemode.h"
#include "modechange.h"
#include "quote.h"
#include "savedir.h"

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

#define AUTHORS "David MacKenzie"

enum Change_status
{
  CH_SUCCEEDED,
  CH_FAILED,
  CH_NO_CHANGE_REQUESTED
};

enum Verbosity
{
  /* Print a message for each file that is processed.  */
  V_high,

  /* Print a message for each file whose attributes we change.  */
  V_changes_only,

  /* Do not be verbose.  This is the default. */
  V_off
};

static int change_dir_mode PARAMS ((const char *dir,
				    const struct mode_change *changes));

/* The name the program was run with. */
char *program_name;

/* If nonzero, change the modes of directories recursively. */
static int recurse;

/* If nonzero, force silence (no error messages). */
static int force_silent;

/* Level of verbosity.  */
static enum Verbosity verbosity = V_off;

/* The argument to the --reference option.  Use the owner and group IDs
   of this file.  This file must exist.  */
static char *reference_file;

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

static struct option const long_options[] =
{
  {"recursive", no_argument, 0, 'R'},
  {"changes", no_argument, 0, 'c'},
  {"silent", no_argument, 0, 'f'},
  {"quiet", no_argument, 0, 'f'},
  {"reference", required_argument, 0, REFERENCE_FILE_OPTION},
  {"verbose", no_argument, 0, 'v'},
  {GETOPT_HELP_OPTION_DECL},
  {GETOPT_VERSION_OPTION_DECL},
  {0, 0, 0, 0}
};

static int
mode_changed (const char *file, mode_t old_mode)
{
  struct stat new_stats;

  if (stat (file, &new_stats))
    {
      if (force_silent == 0)
	error (0, errno, _("getting new attributes of %s"), quote (file));
      return 0;
    }

  return old_mode != new_stats.st_mode;
}

/* Tell the user how/if the MODE of FILE has been changed.
   CHANGED describes what (if anything) has happened. */

static void
describe_change (const char *file, mode_t mode,
		 enum Change_status changed)
{
  char perms[11];		/* "-rwxrwxrwx" ls-style modes. */
  const char *fmt;

  mode_string (mode, perms);
  perms[10] = '\0';		/* `mode_string' does not null terminate. */
  switch (changed)
    {
    case CH_SUCCEEDED:
      fmt = _("mode of %s changed to %04lo (%s)\n");
      break;
    case CH_FAILED:
      fmt = _("failed to change mode of %s to %04lo (%s)\n");
      break;
    case CH_NO_CHANGE_REQUESTED:
      fmt = _("mode of %s retained as %04lo (%s)\n");
      break;
    default:
      abort ();
    }
  printf (fmt, quote (file),
	  (unsigned long) (mode & CHMOD_MODE_BITS), &perms[1]);
}

/* Change the mode of FILE according to the list of operations CHANGES.
   If DEREF_SYMLINK is nonzero and FILE is a symbolic link, change the
   mode of the referenced file.  If DEREF_SYMLINK is zero, ignore symbolic
   links.  Return 0 if successful, 1 if errors occurred. */

static int
change_file_mode (const char *file, const struct mode_change *changes,
		  const int deref_symlink)
{
  struct stat file_stats;
  mode_t newmode;
  int errors = 0;
  int fail;
  int saved_errno;

  if (deref_symlink ? stat (file, &file_stats) : lstat (file, &file_stats))
    {
      if (force_silent == 0)
	error (0, errno, _("failed to get attributes of %s"), quote (file));
      return 1;
    }

#ifdef S_ISLNK
  if (S_ISLNK (file_stats.st_mode))
    return 0;
#endif

  newmode = mode_adjust (file_stats.st_mode, changes);

  fail = chmod (file, newmode);
  saved_errno = errno;

  if (verbosity == V_high
      || (verbosity == V_changes_only
	  && !fail && mode_changed (file, file_stats.st_mode)))
    describe_change (file, newmode, (fail ? CH_FAILED : CH_SUCCEEDED));

  if (fail)
    {
      if (force_silent == 0)
	error (0, saved_errno, _("changing permissions of %s"),
	       quote (file));
      errors = 1;
    }

  if (recurse && S_ISDIR (file_stats.st_mode))
    errors |= change_dir_mode (file, changes);
  return errors;
}

/* Recursively change the modes of the files in directory DIR
   according to the list of operations CHANGES.
   Return 0 if successful, 1 if errors occurred. */

static int
change_dir_mode (const char *dir, const struct mode_change *changes)
{
  char *name_space, *namep;
  char *path;			/* Full path of each entry to process. */
  unsigned dirlength;		/* Length of DIR and '\0'. */
  unsigned filelength;		/* Length of each pathname to process. */
  unsigned pathlength;		/* Bytes allocated for `path'. */
  int errors = 0;

  name_space = savedir (dir);
  if (name_space == NULL)
    {
      if (force_silent == 0)
	error (0, errno, "%s", quote (dir));
      return 1;
    }

  dirlength = strlen (dir) + 1;	/* + 1 is for the trailing '/'. */
  pathlength = dirlength + 1;
  /* Give `path' a dummy value; it will be reallocated before first use. */
  path = xmalloc (pathlength);
  strcpy (path, dir);
  path[dirlength - 1] = '/';

  for (namep = name_space; *namep; namep += filelength - dirlength)
    {
      filelength = dirlength + strlen (namep) + 1;
      if (filelength > pathlength)
	{
	  pathlength = filelength * 2;
	  path = xrealloc (path, pathlength);
	}
      strcpy (path + dirlength, namep);
      errors |= change_file_mode (path, changes, 0);
    }
  free (path);
  free (name_space);
  return errors;
}

void
usage (int status)
{
  if (status != 0)
    fprintf (stderr, _("Try `%s --help' for more information.\n"),
	     program_name);
  else
    {
      printf (_("\
Usage: %s [OPTION]... MODE[,MODE]... FILE...\n\
  or:  %s [OPTION]... OCTAL-MODE FILE...\n\
  or:  %s [OPTION]... --reference=RFILE FILE...\n\
"),
	      program_name, program_name, program_name);
      fputs (_("\
Change the mode of each FILE to MODE.\n\
\n\
  -c, --changes           like verbose but report only when a change is made\n\
  -f, --silent, --quiet   suppress most error messages\n\
  -v, --verbose           output a diagnostic for every file processed\n\
      --reference=RFILE   use RFILE's mode instead of MODE values\n\
  -R, --recursive         change files and directories recursively\n\
"), stdout);
      fputs (HELP_OPTION_DESCRIPTION, stdout);
      fputs (VERSION_OPTION_DESCRIPTION, stdout);
      fputs (_("\
\n\
Each MODE is one or more of the letters ugoa, one of the symbols +-= and\n\
one or more of the letters rwxXstugo.\n\
"), stdout);
      printf (_("\nReport bugs to <%s>.\n"), PACKAGE_BUGREPORT);
    }
  exit (status);
}

/* Parse the ASCII mode given on the command line into a linked list
   of `struct mode_change' and apply that to each file argument. */

int
main (int argc, char **argv)
{
  struct mode_change *changes;
  int errors = 0;
  int modeind = 0;		/* Index of the mode argument in `argv'. */
  int thisind;
  int c;

  program_name = argv[0];
  setlocale (LC_ALL, "");
  bindtextdomain (PACKAGE, LOCALEDIR);
  textdomain (PACKAGE);

  atexit (close_stdout);

  recurse = force_silent = 0;

  while (1)
    {
      thisind = optind ? optind : 1;

      c = getopt_long (argc, argv, "RcfvrwxXstugoa,+-=", long_options, NULL);
      if (c == -1)
	break;

      switch (c)
	{
	case 0:
	  break;
	case 'r':
	case 'w':
	case 'x':
	case 'X':
	case 's':
	case 't':
	case 'u':
	case 'g':
	case 'o':
	case 'a':
	case ',':
	case '+':
	case '-':
	case '=':
	  if (modeind != 0 && modeind != thisind)
	    {
	      static char char_string[2] = {0, 0};
	      char_string[0] = c;
	      error (1, 0, _("invalid character %s in mode string %s"),
		     quote_n (0, char_string), quote_n (1, argv[thisind]));
	    }
	  modeind = thisind;
	  break;
	case REFERENCE_FILE_OPTION:
	  reference_file = optarg;
	  break;
	case 'R':
	  recurse = 1;
	  break;
	case 'c':
	  verbosity = V_changes_only;
	  break;
	case 'f':
	  force_silent = 1;
	  break;
	case 'v':
	  verbosity = V_high;
	  break;
	case_GETOPT_HELP_CHAR;
	case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
	default:
	  usage (1);
	}
    }

  if (modeind == 0 && reference_file == NULL)
    modeind = optind++;

  if (optind >= argc)
    {
      error (0, 0, _("too few arguments"));
      usage (1);
    }

  changes = (reference_file ? mode_create_from_ref (reference_file)
	     : mode_compile (argv[modeind], MODE_MASK_ALL));

  if (changes == MODE_INVALID)
    error (1, 0, _("invalid mode string: %s"), quote (argv[modeind]));
  else if (changes == MODE_MEMORY_EXHAUSTED)
    xalloc_die ();
  else if (changes == MODE_BAD_REFERENCE)
    error (1, errno, _("failed to get attributes of %s"),
	   quote (reference_file));

  for (; optind < argc; ++optind)
    errors |= change_file_mode (argv[optind], changes, 1);

  exit (errors);
}