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.
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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.
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17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * @(#)setmode.c 8.2 (Berkeley) 3/25/94
33 * $FreeBSD: src/lib/libc/gen/setmode.c,v 1.11 2007/01/09 00:27:55 imp Exp $
34 * $DragonFly: src/lib/libc/gen/setmode.c,v 1.7 2005/11/19 22:32:53 swildner Exp $
37 #include "namespace.h"
38 #include <sys/types.h>
50 #include "un-namespace.h"
52 #define SET_LEN 6 /* initial # of bitcmd struct to malloc */
53 #define SET_LEN_INCR 4 /* # of bitcmd structs to add as needed */
55 typedef struct bitcmd
{
63 #define CMD2_GBITS 0x04
64 #define CMD2_OBITS 0x08
65 #define CMD2_UBITS 0x10
67 static BITCMD
*addcmd(BITCMD
*, int, int, int, u_int
);
68 static void compress_mode(BITCMD
*);
70 static void dumpmode(BITCMD
*);
74 * Given the old mode and an array of bitcmd structures, apply the operations
75 * described in the bitcmd structures to the old mode, and return the new mode.
76 * Note that there is no '=' command; a strict assignment is just a '-' (clear
77 * bits) followed by a '+' (set bits).
80 getmode(const void *bbox
, mode_t omode
)
83 mode_t clrval
, newmode
, value
;
85 set
= (const BITCMD
*)bbox
;
87 for (value
= 0;; set
++)
90 * When copying the user, group or other bits around, we "know"
91 * where the bits are in the mode so that we can do shifts to
92 * copy them around. If we don't use shifts, it gets real
93 * grundgy with lots of single bit checks and bit sets.
96 value
= (newmode
& S_IRWXU
) >> 6;
100 value
= (newmode
& S_IRWXG
) >> 3;
104 value
= newmode
& S_IRWXO
;
105 common
: if (set
->cmd2
& CMD2_CLR
) {
107 (set
->cmd2
& CMD2_SET
) ? S_IRWXO
: value
;
108 if (set
->cmd2
& CMD2_UBITS
)
109 newmode
&= ~((clrval
<<6) & set
->bits
);
110 if (set
->cmd2
& CMD2_GBITS
)
111 newmode
&= ~((clrval
<<3) & set
->bits
);
112 if (set
->cmd2
& CMD2_OBITS
)
113 newmode
&= ~(clrval
& set
->bits
);
115 if (set
->cmd2
& CMD2_SET
) {
116 if (set
->cmd2
& CMD2_UBITS
)
117 newmode
|= (value
<<6) & set
->bits
;
118 if (set
->cmd2
& CMD2_GBITS
)
119 newmode
|= (value
<<3) & set
->bits
;
120 if (set
->cmd2
& CMD2_OBITS
)
121 newmode
|= value
& set
->bits
;
126 newmode
|= set
->bits
;
130 newmode
&= ~set
->bits
;
134 if (omode
& (S_IFDIR
|S_IXUSR
|S_IXGRP
|S_IXOTH
))
135 newmode
|= set
->bits
;
141 printf("getmode:%04o -> %04o\n", omode
, newmode
);
147 #define ADDCMD(a, b, c, d) \
148 if (set >= endset) { \
150 setlen += SET_LEN_INCR; \
151 newset = realloc(saveset, sizeof(BITCMD) * setlen); \
158 set = newset + (set - saveset); \
160 endset = newset + (setlen - 2); \
162 set = addcmd(set, (a), (b), (c), (d))
164 #define STANDARD_BITS (S_ISUID|S_ISGID|S_IRWXU|S_IRWXG|S_IRWXO)
167 setmode(const char *p
)
171 BITCMD
*set
, *saveset
, *endset
;
172 sigset_t sigset
, sigoset
;
174 int equalopdone
=0, permXbits
, setlen
;
181 * Get a copy of the mask for the permissions that are mask relative.
182 * Flip the bits, we want what's not set. Since it's possible that
183 * the caller is opening files inside a signal handler, protect them
187 _sigprocmask(SIG_BLOCK
, &sigset
, &sigoset
);
188 umask(mask
= umask(0));
190 _sigprocmask(SIG_SETMASK
, &sigoset
, NULL
);
192 setlen
= SET_LEN
+ 2;
194 if ((set
= malloc((u_int
)(sizeof(BITCMD
) * setlen
))) == NULL
)
197 endset
= set
+ (setlen
- 2);
200 * If an absolute number, get it and return; disallow non-octal digits
203 if (isdigit((unsigned char)*p
)) {
204 perml
= strtol(p
, &ep
, 8);
205 if (*ep
|| perml
< 0 || perml
& ~(STANDARD_BITS
|S_ISTXT
)) {
209 perm
= (mode_t
)perml
;
210 ADDCMD('=', (STANDARD_BITS
|S_ISTXT
), perm
, mask
);
216 * Build list of structures to set/clear/copy bits as described by
217 * each clause of the symbolic mode.
220 /* First, find out which bits might be modified. */
221 for (who
= 0;; ++p
) {
224 who
|= STANDARD_BITS
;
227 who
|= S_ISUID
|S_IRWXU
;
230 who
|= S_ISGID
|S_IRWXG
;
240 getop
: if ((op
= *p
++) != '+' && op
!= '-' && op
!= '=') {
248 for (perm
= 0, permXbits
= 0;; ++p
) {
251 perm
|= S_IRUSR
|S_IRGRP
|S_IROTH
;
254 /* If only "other" bits ignore set-id. */
255 if (!who
|| who
& ~S_IRWXO
)
256 perm
|= S_ISUID
|S_ISGID
;
259 /* If only "other" bits ignore sticky. */
260 if (!who
|| who
& ~S_IRWXO
) {
266 perm
|= S_IWUSR
|S_IWGRP
|S_IWOTH
;
269 permXbits
= S_IXUSR
|S_IXGRP
|S_IXOTH
;
272 perm
|= S_IXUSR
|S_IXGRP
|S_IXOTH
;
278 * When ever we hit 'u', 'g', or 'o', we have
279 * to flush out any partial mode that we have,
280 * and then do the copying of the mode bits.
283 ADDCMD(op
, who
, perm
, mask
);
288 if (op
== '+' && permXbits
) {
289 ADDCMD('X', who
, permXbits
, mask
);
292 ADDCMD(*p
, who
, op
, mask
);
297 * Add any permissions that we haven't already
300 if (perm
|| (op
== '=' && !equalopdone
)) {
303 ADDCMD(op
, who
, perm
, mask
);
307 ADDCMD('X', who
, permXbits
, mask
);
322 printf("Before compress_mode()\n");
325 compress_mode(saveset
);
327 printf("After compress_mode()\n");
334 addcmd(BITCMD
*set
, int op
, int who
, int oparg
, u_int mask
)
339 set
->bits
= who
? who
: STANDARD_BITS
;
348 set
->bits
= (who
? who
: mask
) & oparg
;
356 set
->cmd2
= ((who
& S_IRUSR
) ? CMD2_UBITS
: 0) |
357 ((who
& S_IRGRP
) ? CMD2_GBITS
: 0) |
358 ((who
& S_IROTH
) ? CMD2_OBITS
: 0);
359 set
->bits
= (mode_t
)~0;
361 set
->cmd2
= CMD2_UBITS
| CMD2_GBITS
| CMD2_OBITS
;
366 set
->cmd2
|= CMD2_SET
;
367 else if (oparg
== '-')
368 set
->cmd2
|= CMD2_CLR
;
369 else if (oparg
== '=')
370 set
->cmd2
|= CMD2_SET
|CMD2_CLR
;
378 dumpmode(BITCMD
*set
)
380 for (; set
->cmd
; ++set
)
381 printf("cmd: '%c' bits %04o%s%s%s%s%s%s\n",
382 set
->cmd
, set
->bits
, set
->cmd2
? " cmd2:" : "",
383 set
->cmd2
& CMD2_CLR
? " CLR" : "",
384 set
->cmd2
& CMD2_SET
? " SET" : "",
385 set
->cmd2
& CMD2_UBITS
? " UBITS" : "",
386 set
->cmd2
& CMD2_GBITS
? " GBITS" : "",
387 set
->cmd2
& CMD2_OBITS
? " OBITS" : "");
392 * Given an array of bitcmd structures, compress by compacting consecutive
393 * '+', '-' and 'X' commands into at most 3 commands, one of each. The 'u',
394 * 'g' and 'o' commands continue to be separate. They could probably be
395 * compacted, but it's not worth the effort.
398 compress_mode(BITCMD
*set
)
401 int setbits
, clrbits
, Xbits
, op
;
404 /* Copy over any 'u', 'g' and 'o' commands. */
405 while ((op
= nset
->cmd
) != '+' && op
!= '-' && op
!= 'X') {
411 for (setbits
= clrbits
= Xbits
= 0;; nset
++) {
412 if ((op
= nset
->cmd
) == '-') {
413 clrbits
|= nset
->bits
;
414 setbits
&= ~nset
->bits
;
415 Xbits
&= ~nset
->bits
;
416 } else if (op
== '+') {
417 setbits
|= nset
->bits
;
418 clrbits
&= ~nset
->bits
;
419 Xbits
&= ~nset
->bits
;
420 } else if (op
== 'X')
421 Xbits
|= nset
->bits
& ~setbits
;