2 * Copyright (c) 1989, 1993, 1994
3 * The Regents of the University of California. All rights reserved.
5 * This code is derived from software contributed to Berkeley by
6 * Dave Borman at Cray Research, Inc.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 * must display the following acknowledgement:
18 * This product includes software developed by the University of
19 * California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37 #if defined(LIBC_SCCS) && !defined(lint)
39 static char sccsid[] = "@(#)setmode.c 8.2 (Berkeley) 3/25/94";
41 static const char rcsid[] =
42 "$FreeBSD: src/lib/libc/gen/setmode.c,v 1.5.2.1 2001/03/05 09:34:10 obrien Exp $";
43 #endif /* LIBC_SCCS and not lint */
45 #include <sys/types.h>
57 #define SET_LEN 6 /* initial # of bitcmd struct to malloc */
58 #define SET_LEN_INCR 4 /* # of bitcmd structs to add as needed */
60 typedef struct bitcmd {
68 #define CMD2_GBITS 0x04
69 #define CMD2_OBITS 0x08
70 #define CMD2_UBITS 0x10
72 static BITCMD *addcmd __P((BITCMD *, int, int, int, u_int));
73 static void compress_mode __P((BITCMD *));
75 static void dumpmode __P((BITCMD *));
79 * Given the old mode and an array of bitcmd structures, apply the operations
80 * described in the bitcmd structures to the old mode, and return the new mode.
81 * Note that there is no '=' command; a strict assignment is just a '-' (clear
82 * bits) followed by a '+' (set bits).
90 register mode_t clrval, newmode, value;
94 for (value = 0;; set++)
97 * When copying the user, group or other bits around, we "know"
98 * where the bits are in the mode so that we can do shifts to
99 * copy them around. If we don't use shifts, it gets real
100 * grundgy with lots of single bit checks and bit sets.
103 value = (newmode & S_IRWXU) >> 6;
107 value = (newmode & S_IRWXG) >> 3;
111 value = newmode & S_IRWXO;
112 common: if (set->cmd2 & CMD2_CLR) {
114 (set->cmd2 & CMD2_SET) ? S_IRWXO : value;
115 if (set->cmd2 & CMD2_UBITS)
116 newmode &= ~((clrval<<6) & set->bits);
117 if (set->cmd2 & CMD2_GBITS)
118 newmode &= ~((clrval<<3) & set->bits);
119 if (set->cmd2 & CMD2_OBITS)
120 newmode &= ~(clrval & set->bits);
122 if (set->cmd2 & CMD2_SET) {
123 if (set->cmd2 & CMD2_UBITS)
124 newmode |= (value<<6) & set->bits;
125 if (set->cmd2 & CMD2_GBITS)
126 newmode |= (value<<3) & set->bits;
127 if (set->cmd2 & CMD2_OBITS)
128 newmode |= value & set->bits;
133 newmode |= set->bits;
137 newmode &= ~set->bits;
141 if (omode & (S_IFDIR|S_IXUSR|S_IXGRP|S_IXOTH))
142 newmode |= set->bits;
148 (void)printf("getmode:%04o -> %04o\n", omode, newmode);
154 #define ADDCMD(a, b, c, d) \
155 if (set >= endset) { \
156 register BITCMD *newset; \
157 setlen += SET_LEN_INCR; \
158 newset = realloc(saveset, sizeof(BITCMD) * setlen); \
161 set = newset + (set - saveset); \
163 endset = newset + (setlen - 2); \
165 set = addcmd(set, (a), (b), (c), (d))
167 #define STANDARD_BITS (S_ISUID|S_ISGID|S_IRWXU|S_IRWXG|S_IRWXO)
173 register int perm, who;
175 BITCMD *set, *saveset, *endset;
176 sigset_t sigset, sigoset;
178 int equalopdone=0, permXbits, setlen;
184 * Get a copy of the mask for the permissions that are mask relative.
185 * Flip the bits, we want what's not set. Since it's possible that
186 * the caller is opening files inside a signal handler, protect them
190 (void)sigprocmask(SIG_BLOCK, &sigset, &sigoset);
191 (void)umask(mask = umask(0));
193 (void)sigprocmask(SIG_SETMASK, &sigoset, NULL);
195 setlen = SET_LEN + 2;
197 if ((set = malloc((u_int)(sizeof(BITCMD) * setlen))) == NULL)
200 endset = set + (setlen - 2);
203 * If an absolute number, get it and return; disallow non-octal digits
206 if (isdigit((unsigned char)*p)) {
207 perm = (mode_t)strtol(p, NULL, 8);
208 if (perm & ~(STANDARD_BITS|S_ISTXT)) {
213 if (*p < '0' || *p > '7') {
217 ADDCMD('=', (STANDARD_BITS|S_ISTXT), perm, mask);
222 * Build list of structures to set/clear/copy bits as described by
223 * each clause of the symbolic mode.
226 /* First, find out which bits might be modified. */
227 for (who = 0;; ++p) {
230 who |= STANDARD_BITS;
233 who |= S_ISUID|S_IRWXU;
236 who |= S_ISGID|S_IRWXG;
246 getop: if ((op = *p++) != '+' && op != '-' && op != '=') {
254 for (perm = 0, permXbits = 0;; ++p) {
257 perm |= S_IRUSR|S_IRGRP|S_IROTH;
260 /* If only "other" bits ignore set-id. */
261 if (!who || who & ~S_IRWXO)
262 perm |= S_ISUID|S_ISGID;
265 /* If only "other" bits ignore sticky. */
266 if (!who || who & ~S_IRWXO) {
272 perm |= S_IWUSR|S_IWGRP|S_IWOTH;
275 permXbits = S_IXUSR|S_IXGRP|S_IXOTH;
278 perm |= S_IXUSR|S_IXGRP|S_IXOTH;
284 * When ever we hit 'u', 'g', or 'o', we have
285 * to flush out any partial mode that we have,
286 * and then do the copying of the mode bits.
289 ADDCMD(op, who, perm, mask);
294 if (op == '+' && permXbits) {
295 ADDCMD('X', who, permXbits, mask);
298 ADDCMD(*p, who, op, mask);
303 * Add any permissions that we haven't already
306 if (perm || (op == '=' && !equalopdone)) {
309 ADDCMD(op, who, perm, mask);
313 ADDCMD('X', who, permXbits, mask);
328 (void)printf("Before compress_mode()\n");
331 compress_mode(saveset);
333 (void)printf("After compress_mode()\n");
340 addcmd(set, op, who, oparg, mask)
342 register int oparg, who;
349 set->bits = who ? who : STANDARD_BITS;
358 set->bits = (who ? who : mask) & oparg;
366 set->cmd2 = ((who & S_IRUSR) ? CMD2_UBITS : 0) |
367 ((who & S_IRGRP) ? CMD2_GBITS : 0) |
368 ((who & S_IROTH) ? CMD2_OBITS : 0);
371 set->cmd2 = CMD2_UBITS | CMD2_GBITS | CMD2_OBITS;
376 set->cmd2 |= CMD2_SET;
377 else if (oparg == '-')
378 set->cmd2 |= CMD2_CLR;
379 else if (oparg == '=')
380 set->cmd2 |= CMD2_SET|CMD2_CLR;
389 register BITCMD *set;
391 for (; set->cmd; ++set)
392 (void)printf("cmd: '%c' bits %04o%s%s%s%s%s%s\n",
393 set->cmd, set->bits, set->cmd2 ? " cmd2:" : "",
394 set->cmd2 & CMD2_CLR ? " CLR" : "",
395 set->cmd2 & CMD2_SET ? " SET" : "",
396 set->cmd2 & CMD2_UBITS ? " UBITS" : "",
397 set->cmd2 & CMD2_GBITS ? " GBITS" : "",
398 set->cmd2 & CMD2_OBITS ? " OBITS" : "");
403 * Given an array of bitcmd structures, compress by compacting consecutive
404 * '+', '-' and 'X' commands into at most 3 commands, one of each. The 'u',
405 * 'g' and 'o' commands continue to be separate. They could probably be
406 * compacted, but it's not worth the effort.
410 register BITCMD *set;
412 register BITCMD *nset;
413 register int setbits, clrbits, Xbits, op;
416 /* Copy over any 'u', 'g' and 'o' commands. */
417 while ((op = nset->cmd) != '+' && op != '-' && op != 'X') {
423 for (setbits = clrbits = Xbits = 0;; nset++) {
424 if ((op = nset->cmd) == '-') {
425 clrbits |= nset->bits;
426 setbits &= ~nset->bits;
427 Xbits &= ~nset->bits;
428 } else if (op == '+') {
429 setbits |= nset->bits;
430 clrbits &= ~nset->bits;
431 Xbits &= ~nset->bits;
432 } else if (op == 'X')
433 Xbits |= nset->bits & ~setbits;