2 * Implement the core of the --chmod option.
4 * Copyright (C) 2002 Scott Howard
5 * Copyright (C) 2005-2009 Wayne Davison
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 3 of the License, or
10 * (at your option) any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License along
18 * with this program; if not, visit the http://fsf.org website.
23 extern mode_t orig_umask;
25 #define FLAG_X_KEEP (1<<0)
26 #define FLAG_DIRS_ONLY (1<<1)
27 #define FLAG_FILES_ONLY (1<<2)
29 struct chmod_mode_struct {
30 struct chmod_mode_struct *next;
40 #define STATE_1ST_HALF 1
41 #define STATE_2ND_HALF 2
43 /* Parse a chmod-style argument, and break it down into one or more AND/OR
44 * pairs in a linked list. We return a pointer to new items on succcess
45 * (appending the items to the specified list), or NULL on error. */
46 struct chmod_mode_struct *parse_chmod(const char *modestr,
47 struct chmod_mode_struct **root_mode_ptr)
49 int state = STATE_1ST_HALF;
50 int where = 0, what = 0, op = 0, topbits = 0, topoct = 0, flags = 0;
51 struct chmod_mode_struct *first_mode = NULL, *curr_mode = NULL,
54 while (state != STATE_ERROR) {
55 if (!*modestr || *modestr == ',') {
62 prev_mode = curr_mode;
63 curr_mode = new_array(struct chmod_mode_struct, 1);
65 prev_mode->next = curr_mode;
67 first_mode = curr_mode;
68 curr_mode->next = NULL;
74 bits = (where * what) & ~orig_umask;
79 curr_mode->ModeAND = CHMOD_BITS;
80 curr_mode->ModeOR = bits + topoct;
83 curr_mode->ModeAND = CHMOD_BITS - bits - topoct;
84 curr_mode->ModeOR = 0;
87 curr_mode->ModeAND = CHMOD_BITS - (where * 7) - (topoct ? topbits : 0);
88 curr_mode->ModeOR = bits + topoct;
92 curr_mode->flags = flags;
98 state = STATE_1ST_HALF;
99 where = what = op = topoct = topbits = flags = 0;
102 if (state != STATE_2ND_HALF) {
105 if (flags & FLAG_FILES_ONLY)
107 flags |= FLAG_DIRS_ONLY;
110 if (flags & FLAG_DIRS_ONLY)
112 flags |= FLAG_FILES_ONLY;
130 state = STATE_2ND_HALF;
134 state = STATE_2ND_HALF;
138 state = STATE_2ND_HALF;
153 flags |= FLAG_X_KEEP;
175 if (state == STATE_ERROR) {
176 free_chmod_mode(first_mode);
180 if (!(curr_mode = *root_mode_ptr))
181 *root_mode_ptr = first_mode;
183 while (curr_mode->next)
184 curr_mode = curr_mode->next;
185 curr_mode->next = first_mode;
192 /* Takes an existing file permission and a list of AND/OR changes, and
193 * create a new permissions. */
194 int tweak_mode(int mode, struct chmod_mode_struct *chmod_modes)
196 int IsX = mode & 0111;
197 int NonPerm = mode & ~CHMOD_BITS;
199 for ( ; chmod_modes; chmod_modes = chmod_modes->next) {
200 if ((chmod_modes->flags & FLAG_DIRS_ONLY) && !S_ISDIR(NonPerm))
202 if ((chmod_modes->flags & FLAG_FILES_ONLY) && S_ISDIR(NonPerm))
204 mode &= chmod_modes->ModeAND;
205 if ((chmod_modes->flags & FLAG_X_KEEP) && !IsX && !S_ISDIR(NonPerm))
206 mode |= chmod_modes->ModeOR & ~0111;
208 mode |= chmod_modes->ModeOR;
211 return mode | NonPerm;
214 /* Free the linked list created by parse_chmod. */
215 int free_chmod_mode(struct chmod_mode_struct *chmod_modes)
217 struct chmod_mode_struct *next;
219 while (chmod_modes) {
220 next = chmod_modes->next;