summaryrefslogtreecommitdiff
path: root/src/chmod.c
blob: b508b45ede1aaaee0246dc52e8291cb76a8d134b (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
/* chmod -- change permission modes of files
   Copyright (C) 1989, 1990, 1991, 1995 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., 675 Mass Ave, Cambridge, MA 02139, USA.  */

/* Options:
   -R	Recursively change modes of directory contents.
   -c	Verbosely describe only files whose modes actually change.
   -f	Do not print error messages about files.
   -v	Verbosely describe changed modes.

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

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

#include "modechange.h"
#include "system.h"
#include "version.h"
#include "error.h"

void mode_string ();
char *savedir ();
void strip_trailing_slashes ();
char *xmalloc ();
char *xrealloc ();

static int change_dir_mode __P ((char *dir, struct mode_change *changes,
				 struct stat *statp));

/* 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;

/* If nonzero, describe the modes we set. */
static int verbose;

/* If nonzero, describe only modes that change. */
static int changes_only;

/* If nonzero, display usage information and exit.  */
static int show_help;

/* If nonzero, print the version on standard output and exit.  */
static int show_version;

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'},
  {"verbose", no_argument, 0, 'v'},
  {"help", no_argument, &show_help, 1},
  {"version", no_argument, &show_version, 1},
  {0, 0, 0, 0}
};

/* Tell the user the mode MODE that file FILE has been set to;
   if CHANGED is zero, FILE had that mode already. */

static void
describe_change (char *file, short unsigned int mode, int changed)
{
  char perms[11];		/* "-rwxrwxrwx" ls-style modes. */

  mode_string (mode, perms);
  perms[10] = '\0';		/* `mode_string' does not null terminate. */
  if (changed)
    printf (_("mode of %s changed to %04o (%s)\n"),
	    file, mode & 07777, &perms[1]);
  else
    printf (_("mode of %s retained as %04o (%s)\n"),
	    file, mode & 07777, &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 (char *file, struct mode_change *changes, int deref_symlink)
{
  struct stat file_stats;
  unsigned short newmode;
  int errors = 0;

  if (lstat (file, &file_stats))
    {
      if (force_silent == 0)
	error (0, errno, "%s", file);
      return 1;
    }
#ifdef S_ISLNK
  if (S_ISLNK (file_stats.st_mode))
    {
      if (! deref_symlink)
	return 0;
      else
	if (stat (file, &file_stats))
	  {
	    if (force_silent == 0)
	      error (0, errno, "%s", file);
	    return 1;
	  }
    }
#endif

  newmode = mode_adjust (file_stats.st_mode, changes);

  if (newmode != (file_stats.st_mode & 07777))
    {
      if (verbose)
	describe_change (file, newmode, 1);
      if (chmod (file, (int) newmode))
	{
	  if (force_silent == 0)
	    error (0, errno, "%s", file);
	  errors = 1;
	}
    }
  else if (verbose && changes_only == 0)
    describe_change (file, newmode, 0);

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

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

static int
change_dir_mode (char *dir, struct mode_change *changes, struct stat *statp)
{
  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;

  errno = 0;
  name_space = savedir (dir, statp->st_size);
  if (name_space == NULL)
    {
      if (errno)
	{
	  if (force_silent == 0)
	    error (0, errno, "%s", dir);
	  return 1;
	}
      else
	error (1, 0, _("virtual memory exhausted"));
    }

  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;
}

static 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\
"),
	      program_name, program_name);
      printf (_("\
\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\
  -R, --recursive         change files and directories recursively\n\
      --help              display this help and exit\n\
      --version           output version information and exit\n\
\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"));
    }
  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. */

void
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];
  recurse = force_silent = verbose = changes_only = 0;

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

      c = getopt_long (argc, argv, "RcfvrwxXstugoa,+-=", long_options,
		       (int *) 0);
      if (c == EOF)
	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)
	    error (1, 0, _("invalid mode"));
	  modeind = thisind;
	  break;
	case 'R':
	  recurse = 1;
	  break;
	case 'c':
	  verbose = 1;
	  changes_only = 1;
	  break;
	case 'f':
	  force_silent = 1;
	  break;
	case 'v':
	  verbose = 1;
	  break;
	default:
	  usage (1);
	}
    }

  if (show_version)
    {
      printf ("chmod - %s\n", version_string);
      exit (0);
    }

  if (show_help)
    usage (0);

  if (modeind == 0)
    modeind = optind++;

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

  changes = mode_compile (argv[modeind],
			  MODE_MASK_EQUALS | MODE_MASK_PLUS | MODE_MASK_MINUS);
  if (changes == MODE_INVALID)
    error (1, 0, _("invalid mode"));
  else if (changes == MODE_MEMORY_EXHAUSTED)
    error (1, 0, _("virtual memory exhausted"));

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

  exit (errors);
}