setmode.c@ 902

Last change on this file since 902 was 616, checked in by bird, 18 years ago
Ported the new setmode to MSC.
Property svn:eol-style set to `native` Property svn:keywords set to `Author Date Id Revision`
File size: 11.4 KB

Line
1	/* $NetBSD: setmode.c,v 1.30 2003/08/07 16:42:56 agc Exp $ */
2
3	/*
4	* Copyright (c) 1989, 1993, 1994
5	* The Regents of the University of California. All rights reserved.
6	*
7	* This code is derived from software contributed to Berkeley by
8	* Dave Borman at Cray Research, Inc.
9	*
10	* Redistribution and use in source and binary forms, with or without
11	* modification, are permitted provided that the following conditions
12	* are met:
13	* 1. Redistributions of source code must retain the above copyright
14	* notice, this list of conditions and the following disclaimer.
15	* 2. Redistributions in binary form must reproduce the above copyright
16	* notice, this list of conditions and the following disclaimer in the
17	* documentation and/or other materials provided with the distribution.
18	* 3. Neither the name of the University nor the names of its contributors
19	* may be used to endorse or promote products derived from this software
20	* without specific prior written permission.
21	*
22	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32	* SUCH DAMAGE.
33	*/
34
35	/#include <sys/cdefs.h>/
36	#if defined(LIBC_SCCS) && !defined(lint)
37	#if 0
38	static char sccsid[] = "@(#)setmode.c 8.2 (Berkeley) 3/25/94";
39	#else
40	__RCSID("$NetBSD: setmode.c,v 1.30 2003/08/07 16:42:56 agc Exp $");
41	#endif
42	#endif /* LIBC_SCCS and not lint */
43
44	/#include "namespace.h"/
45	#include <sys/types.h>
46	#include <sys/stat.h>
47
48	#include <assert.h>
49	#include <ctype.h>
50	#include <errno.h>
51	#include <signal.h>
52	#include <stdlib.h>
53	#ifndef _MSC_VER
54	#include <unistd.h>
55	#else
56	#include "mscfakes.h"
57	#endif
58
59	#ifdef SETMODE_DEBUG
60	#include <stdio.h>
61	#endif
62
63	/*#ifdef __weak_alias
64	__weak_alias(getmode,_getmode)
65	__weak_alias(setmode,_setmode)
66	#endif*/
67
68	#define SET_LEN 6 /* initial # of bitcmd struct to malloc */
69	#define SET_LEN_INCR 4 /* # of bitcmd structs to add as needed */
70
71	typedef struct bitcmd {
72	char cmd;
73	char cmd2;
74	mode_t bits;
75	} BITCMD;
76
77	#define CMD2_CLR 0x01
78	#define CMD2_SET 0x02
79	#define CMD2_GBITS 0x04
80	#define CMD2_OBITS 0x08
81	#define CMD2_UBITS 0x10
82
83	static BITCMD addcmd(BITCMD , int, int, int, u_int);
84	static void compress_mode(BITCMD *);
85	#ifdef SETMODE_DEBUG
86	static void dumpmode(BITCMD *);
87	#endif
88
89	#ifndef _DIAGASSERT
90	# define _DIAGASSERT assert
91	#endif
92
93	#ifndef S_ISTXT
94	# ifdef S_ISVTX
95	# define S_ISTXT S_ISVTX
96	# else
97	# define S_ISTXT 0
98	# endif
99	#endif /* !S_ISTXT */
100
101	/*
102	* Given the old mode and an array of bitcmd structures, apply the operations
103	* described in the bitcmd structures to the old mode, and return the new mode.
104	* Note that there is no '=' command; a strict assignment is just a '-' (clear
105	* bits) followed by a '+' (set bits).
106	*/
107	mode_t
108	getmode(bbox, omode)
109	const void *bbox;
110	mode_t omode;
111	{
112	const BITCMD *set;
113	mode_t clrval, newmode, value;
114
115	_DIAGASSERT(bbox != NULL);
116
117	set = (const BITCMD *)bbox;
118	newmode = omode;
119	for (value = 0;; set++)
120	switch(set->cmd) {
121	/*
122	* When copying the user, group or other bits around, we "know"
123	* where the bits are in the mode so that we can do shifts to
124	* copy them around. If we don't use shifts, it gets real
125	* grundgy with lots of single bit checks and bit sets.
126	*/
127	case 'u':
128	value = (newmode & S_IRWXU) >> 6;
129	goto common;
130
131	case 'g':
132	value = (newmode & S_IRWXG) >> 3;
133	goto common;
134
135	case 'o':
136	value = newmode & S_IRWXO;
137	common: if (set->cmd2 & CMD2_CLR) {
138	clrval =
139	(set->cmd2 & CMD2_SET) ? S_IRWXO : value;
140	if (set->cmd2 & CMD2_UBITS)
141	newmode &= ~((clrval<<6) & set->bits);
142	if (set->cmd2 & CMD2_GBITS)
143	newmode &= ~((clrval<<3) & set->bits);
144	if (set->cmd2 & CMD2_OBITS)
145	newmode &= ~(clrval & set->bits);
146	}
147	if (set->cmd2 & CMD2_SET) {
148	if (set->cmd2 & CMD2_UBITS)
149	newmode \|= (value<<6) & set->bits;
150	if (set->cmd2 & CMD2_GBITS)
151	newmode \|= (value<<3) & set->bits;
152	if (set->cmd2 & CMD2_OBITS)
153	newmode \|= value & set->bits;
154	}
155	break;
156
157	case '+':
158	newmode \|= set->bits;
159	break;
160
161	case '-':
162	newmode &= ~set->bits;
163	break;
164
165	case 'X':
166	if (omode & (S_IFDIR\|S_IXUSR\|S_IXGRP\|S_IXOTH))
167	newmode \|= set->bits;
168	break;
169
170	case '\0':
171	default:
172	#ifdef SETMODE_DEBUG
173	(void)printf("getmode:%04o -> %04o\n", omode, newmode);
174	#endif
175	return (newmode);
176	}
177	}
178
179	#define ADDCMD(a, b, c, d) do { \
180	if (set >= endset) { \
181	BITCMD *newset; \
182	setlen += SET_LEN_INCR; \
183	newset = realloc(saveset, sizeof(BITCMD) * setlen); \
184	if (newset == NULL) { \
185	free(saveset); \
186	return (NULL); \
187	} \
188	set = newset + (set - saveset); \
189	saveset = newset; \
190	endset = newset + (setlen - 2); \
191	} \
192	set = addcmd(set, (a), (b), (c), (d)); \
193	} while (/CONSTCOND/0)
194
195	#define STANDARD_BITS (S_ISUID\|S_ISGID\|S_IRWXU\|S_IRWXG\|S_IRWXO)
196
197	void *
198	setmode(p)
199	const char *p;
200	{
201	int perm, who;
202	char op, *ep;
203	BITCMD set, saveset, *endset;
204	#ifndef _MSC_VER
205	sigset_t signset, sigoset;
206	#endif
207	mode_t mask;
208	int equalopdone = 0; /* pacify gcc */
209	int permXbits, setlen;
210
211	if (!*p)
212	return (NULL);
213
214	/*
215	* Get a copy of the mask for the permissions that are mask relative.
216	* Flip the bits, we want what's not set. Since it's possible that
217	* the caller is opening files inside a signal handler, protect them
218	* as best we can.
219	*/
220	#ifndef _MSC_VER
221	sigfillset(&signset);
222	(void)sigprocmask(SIG_BLOCK, &signset, &sigoset);
223	#endif
224	(void)umask(mask = umask(0));
225	mask = ~mask;
226	#ifndef _MSC_VER
227	(void)sigprocmask(SIG_SETMASK, &sigoset, NULL);
228	#endif
229
230	setlen = SET_LEN + 2;
231
232	if ((set = malloc((u_int)(sizeof(BITCMD) * setlen))) == NULL)
233	return (NULL);
234	saveset = set;
235	endset = set + (setlen - 2);
236
237	/*
238	* If an absolute number, get it and return; disallow non-octal digits
239	* or illegal bits.
240	*/
241	if (isdigit((unsigned char)*p)) {
242	perm = (mode_t)strtol(p, &ep, 8);
243	if (*ep \|\| perm & ~(STANDARD_BITS\|S_ISTXT)) {
244	free(saveset);
245	return (NULL);
246	}
247	ADDCMD('=', (STANDARD_BITS\|S_ISTXT), perm, mask);
248	set->cmd = 0;
249	return (saveset);
250	}
251
252	/*
253	* Build list of structures to set/clear/copy bits as described by
254	* each clause of the symbolic mode.
255	*/
256	for (;;) {
257	/* First, find out which bits might be modified. */
258	for (who = 0;; ++p) {
259	switch (*p) {
260	case 'a':
261	who \|= STANDARD_BITS;
262	break;
263	case 'u':
264	who \|= S_ISUID\|S_IRWXU;
265	break;
266	case 'g':
267	who \|= S_ISGID\|S_IRWXG;
268	break;
269	case 'o':
270	who \|= S_IRWXO;
271	break;
272	default:
273	goto getop;
274	}
275	}
276
277	getop: if ((op = *p++) != '+' && op != '-' && op != '=') {
278	free(saveset);
279	return (NULL);
280	}
281	if (op == '=')
282	equalopdone = 0;
283
284	who &= ~S_ISTXT;
285	for (perm = 0, permXbits = 0;; ++p) {
286	switch (*p) {
287	case 'r':
288	perm \|= S_IRUSR\|S_IRGRP\|S_IROTH;
289	break;
290	case 's':
291	/*
292	* If specific bits where requested and
293	* only "other" bits ignore set-id.
294	*/
295	if (who == 0 \|\| (who & ~S_IRWXO))
296	perm \|= S_ISUID\|S_ISGID;
297	break;
298	case 't':
299	/*
300	* If specific bits where requested and
301	* only "other" bits ignore set-id.
302	*/
303	if (who == 0 \|\| (who & ~S_IRWXO)) {
304	who \|= S_ISTXT;
305	perm \|= S_ISTXT;
306	}
307	break;
308	case 'w':
309	perm \|= S_IWUSR\|S_IWGRP\|S_IWOTH;
310	break;
311	case 'X':
312	permXbits = S_IXUSR\|S_IXGRP\|S_IXOTH;
313	break;
314	case 'x':
315	perm \|= S_IXUSR\|S_IXGRP\|S_IXOTH;
316	break;
317	case 'u':
318	case 'g':
319	case 'o':
320	/*
321	* When ever we hit 'u', 'g', or 'o', we have
322	* to flush out any partial mode that we have,
323	* and then do the copying of the mode bits.
324	*/
325	if (perm) {
326	ADDCMD(op, who, perm, mask);
327	perm = 0;
328	}
329	if (op == '=')
330	equalopdone = 1;
331	if (op == '+' && permXbits) {
332	ADDCMD('X', who, permXbits, mask);
333	permXbits = 0;
334	}
335	ADDCMD(*p, who, op, mask);
336	break;
337
338	default:
339	/*
340	* Add any permissions that we haven't already
341	* done.
342	*/
343	if (perm \|\| (op == '=' && !equalopdone)) {
344	if (op == '=')
345	equalopdone = 1;
346	ADDCMD(op, who, perm, mask);
347	perm = 0;
348	}
349	if (permXbits) {
350	ADDCMD('X', who, permXbits, mask);
351	permXbits = 0;
352	}
353	goto apply;
354	}
355	}
356
357	apply: if (!*p)
358	break;
359	if (*p != ',')
360	goto getop;
361	++p;
362	}
363	set->cmd = 0;
364	#ifdef SETMODE_DEBUG
365	(void)printf("Before compress_mode()\n");
366	dumpmode(saveset);
367	#endif
368	compress_mode(saveset);
369	#ifdef SETMODE_DEBUG
370	(void)printf("After compress_mode()\n");
371	dumpmode(saveset);
372	#endif
373	return (saveset);
374	}
375
376	static BITCMD *
377	addcmd(set, op, who, oparg, mask)
378	BITCMD *set;
379	int oparg, who;
380	int op;
381	u_int mask;
382	{
383
384	_DIAGASSERT(set != NULL);
385
386	switch (op) {
387	case '=':
388	set->cmd = '-';
389	set->bits = who ? who : STANDARD_BITS;
390	set++;
391
392	op = '+';
393	/* FALLTHROUGH */
394	case '+':
395	case '-':
396	case 'X':
397	set->cmd = op;
398	set->bits = (who ? who : mask) & oparg;
399	break;
400
401	case 'u':
402	case 'g':
403	case 'o':
404	set->cmd = op;
405	if (who) {
406	set->cmd2 = ((who & S_IRUSR) ? CMD2_UBITS : 0) \|
407	((who & S_IRGRP) ? CMD2_GBITS : 0) \|
408	((who & S_IROTH) ? CMD2_OBITS : 0);
409	set->bits = (mode_t)~0;
410	} else {
411	set->cmd2 = CMD2_UBITS \| CMD2_GBITS \| CMD2_OBITS;
412	set->bits = mask;
413	}
414
415	if (oparg == '+')
416	set->cmd2 \|= CMD2_SET;
417	else if (oparg == '-')
418	set->cmd2 \|= CMD2_CLR;
419	else if (oparg == '=')
420	set->cmd2 \|= CMD2_SET\|CMD2_CLR;
421	break;
422	}
423	return (set + 1);
424	}
425
426	#ifdef SETMODE_DEBUG
427	static void
428	dumpmode(set)
429	BITCMD *set;
430	{
431
432	_DIAGASSERT(set != NULL);
433
434	for (; set->cmd; ++set)
435	(void)printf("cmd: '%c' bits %04o%s%s%s%s%s%s\n",
436	set->cmd, set->bits, set->cmd2 ? " cmd2:" : "",
437	set->cmd2 & CMD2_CLR ? " CLR" : "",
438	set->cmd2 & CMD2_SET ? " SET" : "",
439	set->cmd2 & CMD2_UBITS ? " UBITS" : "",
440	set->cmd2 & CMD2_GBITS ? " GBITS" : "",
441	set->cmd2 & CMD2_OBITS ? " OBITS" : "");
442	}
443	#endif
444
445	/*
446	* Given an array of bitcmd structures, compress by compacting consecutive
447	* '+', '-' and 'X' commands into at most 3 commands, one of each. The 'u',
448	* 'g' and 'o' commands continue to be separate. They could probably be
449	* compacted, but it's not worth the effort.
450	*/
451	static void
452	compress_mode(set)
453	BITCMD *set;
454	{
455	BITCMD *nset;
456	int setbits, clrbits, Xbits, op;
457
458	_DIAGASSERT(set != NULL);
459
460	for (nset = set;;) {
461	/* Copy over any 'u', 'g' and 'o' commands. */
462	while ((op = nset->cmd) != '+' && op != '-' && op != 'X') {
463	set++ = nset++;
464	if (!op)
465	return;
466	}
467
468	for (setbits = clrbits = Xbits = 0;; nset++) {
469	if ((op = nset->cmd) == '-') {
470	clrbits \|= nset->bits;
471	setbits &= ~nset->bits;
472	Xbits &= ~nset->bits;
473	} else if (op == '+') {
474	setbits \|= nset->bits;
475	clrbits &= ~nset->bits;
476	Xbits &= ~nset->bits;
477	} else if (op == 'X')
478	Xbits \|= nset->bits & ~setbits;
479	else
480	break;
481	}
482	if (clrbits) {
483	set->cmd = '-';
484	set->cmd2 = 0;
485	set->bits = clrbits;
486	set++;
487	}
488	if (setbits) {
489	set->cmd = '+';
490	set->cmd2 = 0;
491	set->bits = setbits;
492	set++;
493	}
494	if (Xbits) {
495	set->cmd = 'X';
496	set->cmd2 = 0;
497	set->bits = Xbits;
498	set++;
499	}
500	}
501	}

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source: kBuild/trunk/src/gmakenew/kmkbuiltin/setmode.c@ 902

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