[apple/libc.git] / gen / FreeBSD / setmode.c

/*
 * Copyright (c) 1989, 1993, 1994
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Dave Borman at Cray Research, Inc.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)setmode.c	8.2 (Berkeley) 3/25/94";
#endif /* LIBC_SCCS and not lint */
#include <sys/cdefs.h>
__FBSDID("$FreeBSD: src/lib/libc/gen/setmode.c,v 1.11 2007/01/09 00:27:55 imp Exp $");

#include "namespace.h"
#include <sys/types.h>
#include <sys/stat.h>

#include <ctype.h>
#include <signal.h>
#include <stddef.h>
#include <stdlib.h>
#include <unistd.h>

#ifdef SETMODE_DEBUG
#include <stdio.h>
#endif
#include "un-namespace.h"

#define	SET_LEN	6		/* initial # of bitcmd struct to malloc */
#define	SET_LEN_INCR 4		/* # of bitcmd structs to add as needed */

typedef struct bitcmd {
	char	cmd;
	char	cmd2;
	mode_t	bits;
} BITCMD;

#define	CMD2_CLR	0x01
#define	CMD2_SET	0x02
#define	CMD2_GBITS	0x04
#define	CMD2_OBITS	0x08
#define	CMD2_UBITS	0x10

static BITCMD	*addcmd(BITCMD *, int, int, int, u_int);
static void	 compress_mode(BITCMD *);
#ifdef SETMODE_DEBUG
static void	 dumpmode(BITCMD *);
#endif

/*
 * Given the old mode and an array of bitcmd structures, apply the operations
 * described in the bitcmd structures to the old mode, and return the new mode.
 * Note that there is no '=' command; a strict assignment is just a '-' (clear
 * bits) followed by a '+' (set bits).
 */
mode_t
getmode(const void *bbox, mode_t omode)
{
	const BITCMD *set;
	mode_t clrval, newmode, value;

	set = (const BITCMD *)bbox;
	newmode = omode;
	for (value = 0;; set++)
		switch(set->cmd) {
		/*
		 * When copying the user, group or other bits around, we "know"
		 * where the bits are in the mode so that we can do shifts to
		 * copy them around.  If we don't use shifts, it gets real
		 * grundgy with lots of single bit checks and bit sets.
		 */
		case 'u':
			value = (newmode & S_IRWXU) >> 6;
			goto common;

		case 'g':
			value = (newmode & S_IRWXG) >> 3;
			goto common;

		case 'o':
			value = newmode & S_IRWXO;
common:			if (set->cmd2 & CMD2_CLR) {
				clrval =
				    (set->cmd2 & CMD2_SET) ?  S_IRWXO : value;
				if (set->cmd2 & CMD2_UBITS)
					newmode &= ~((clrval<<6) & set->bits);
				if (set->cmd2 & CMD2_GBITS)
					newmode &= ~((clrval<<3) & set->bits);
				if (set->cmd2 & CMD2_OBITS)
					newmode &= ~(clrval & set->bits);
			}
			if (set->cmd2 & CMD2_SET) {
				if (set->cmd2 & CMD2_UBITS)
					newmode |= (value<<6) & set->bits;
				if (set->cmd2 & CMD2_GBITS)
					newmode |= (value<<3) & set->bits;
				if (set->cmd2 & CMD2_OBITS)
					newmode |= value & set->bits;
			}
			break;

		case '+':
			newmode |= set->bits;
			break;

		case '-':
			newmode &= ~set->bits;
			break;

		case 'X':
			if (omode & (S_IFDIR|S_IXUSR|S_IXGRP|S_IXOTH))
				newmode |= set->bits;
			break;

		case '\0':
		default:
#ifdef SETMODE_DEBUG
			(void)printf("getmode:%04o -> %04o\n", omode, newmode);
#endif
			return (newmode);
		}
}

#define	ADDCMD(a, b, c, d)						\
	if (set >= endset) {						\
		BITCMD *newset;						\
		setlen += SET_LEN_INCR;					\
		newset = realloc(saveset, sizeof(BITCMD) * setlen);	\
		if (!newset) {						\
			if (saveset)					\
				free(saveset);				\
			saveset = NULL;					\
			return (NULL);					\
		}							\
		set = newset + (set - saveset);				\
		saveset = newset;					\
		endset = newset + (setlen - 2);				\
	}								\
	set = addcmd(set, (a), (b), (c), (d))

#define	STANDARD_BITS	(S_ISUID|S_ISGID|S_IRWXU|S_IRWXG|S_IRWXO)

void *
setmode(const char *p)
{
	int perm, who;
	char op, *ep;
	BITCMD *set, *saveset, *endset;
	sigset_t sigset, sigoset;
	mode_t mask;
	int equalopdone=0, permXbits, setlen;
	long perml;

	if (!*p)
		return (NULL);

	/*
	 * Get a copy of the mask for the permissions that are mask relative.
	 * Flip the bits, we want what's not set.  Since it's possible that
	 * the caller is opening files inside a signal handler, protect them
	 * as best we can.
	 */
	sigfillset(&sigset);
        (void)_sigprocmask(SIG_BLOCK, &sigset, &sigoset);
	(void)umask(mask = umask(0));
	mask = ~mask;
        (void)_sigprocmask(SIG_SETMASK, &sigoset, NULL);

	setlen = SET_LEN + 2;

	if ((set = malloc((u_int)(sizeof(BITCMD) * setlen))) == NULL)
		return (NULL);
	saveset = set;
	endset = set + (setlen - 2);

	/*
	 * If an absolute number, get it and return; disallow non-octal digits
	 * or illegal bits.
	 */
	if (isdigit((unsigned char)*p)) {
		perml = strtol(p, &ep, 8);
		if (*ep || perml < 0 || perml & ~(STANDARD_BITS|S_ISTXT)) {
			free(saveset);
			return (NULL);
		}
		perm = (mode_t)perml;
		ADDCMD('=', (STANDARD_BITS|S_ISTXT), perm, mask);
		set->cmd = 0;
		return (saveset);
	}

	/*
	 * Build list of structures to set/clear/copy bits as described by
	 * each clause of the symbolic mode.
	 */
	for (;;) {
		/* First, find out which bits might be modified. */
		for (who = 0;; ++p) {
			switch (*p) {
			case 'a':
				who |= STANDARD_BITS;
				break;
			case 'u':
				who |= S_ISUID|S_IRWXU;
				break;
			case 'g':
				who |= S_ISGID|S_IRWXG;
				break;
			case 'o':
				who |= S_IRWXO;
				break;
			default:
				goto getop;
			}
		}

getop:		if ((op = *p++) != '+' && op != '-' && op != '=') {
			free(saveset);
			return (NULL);
		}
		if (op == '=')
			equalopdone = 0;

		who &= ~S_ISTXT;
		for (perm = 0, permXbits = 0;; ++p) {
			switch (*p) {
			case 'r':
				perm |= S_IRUSR|S_IRGRP|S_IROTH;
				break;
			case 's':
				/* If only "other" bits ignore set-id. */
				if (!who || who & ~S_IRWXO)
					perm |= S_ISUID|S_ISGID;
				break;
			case 't':
				/* If only "other" bits ignore sticky. */
				if (!who || who & ~S_IRWXO) {
					who |= S_ISTXT;
					perm |= S_ISTXT;
				}
				break;
			case 'w':
				perm |= S_IWUSR|S_IWGRP|S_IWOTH;
				break;
			case 'X':
				permXbits = S_IXUSR|S_IXGRP|S_IXOTH;
				break;
			case 'x':
				perm |= S_IXUSR|S_IXGRP|S_IXOTH;
				break;
			case 'u':
			case 'g':
			case 'o':
				/*
				 * When ever we hit 'u', 'g', or 'o', we have
				 * to flush out any partial mode that we have,
				 * and then do the copying of the mode bits.
				 */
				if (perm) {
					ADDCMD(op, who, perm, mask);
					perm = 0;
				}
				if (op == '=')
					equalopdone = 1;
				if (op == '+' && permXbits) {
					ADDCMD('X', who, permXbits, mask);
					permXbits = 0;
				}
				ADDCMD(*p, who, op, mask);
				break;

			default:
				/*
				 * Add any permissions that we haven't already
				 * done.
				 */
				if (perm || (op == '=' && !equalopdone)) {
					if (op == '=')
						equalopdone = 1;
					ADDCMD(op, who, perm, mask);
					perm = 0;
				}
				if (permXbits) {
					ADDCMD('X', who, permXbits, mask);
					permXbits = 0;
				}
				goto apply;
			}
		}

apply:		if (!*p)
			break;
		if (*p != ',')
			goto getop;
		++p;
	}
	set->cmd = 0;
#ifdef SETMODE_DEBUG
	(void)printf("Before compress_mode()\n");
	dumpmode(saveset);
#endif
	compress_mode(saveset);
#ifdef SETMODE_DEBUG
	(void)printf("After compress_mode()\n");
	dumpmode(saveset);
#endif
	return (saveset);
}

static BITCMD *
addcmd(BITCMD *set, int op, int who, int oparg, u_int mask)
{
	switch (op) {
	case '=':
		set->cmd = '-';
		set->bits = who ? who : STANDARD_BITS;
		set++;

		op = '+';
		/* FALLTHROUGH */
	case '+':
	case '-':
	case 'X':
		set->cmd = op;
		set->bits = (who ? who : mask) & oparg;
		break;

	case 'u':
	case 'g':
	case 'o':
		set->cmd = op;
		if (who) {
			set->cmd2 = ((who & S_IRUSR) ? CMD2_UBITS : 0) |
				    ((who & S_IRGRP) ? CMD2_GBITS : 0) |
				    ((who & S_IROTH) ? CMD2_OBITS : 0);
			set->bits = (mode_t)~0;
		} else {
			set->cmd2 = CMD2_UBITS | CMD2_GBITS | CMD2_OBITS;
			set->bits = mask;
		}

		if (oparg == '+')
			set->cmd2 |= CMD2_SET;
		else if (oparg == '-')
			set->cmd2 |= CMD2_CLR;
		else if (oparg == '=')
			set->cmd2 |= CMD2_SET|CMD2_CLR;
		break;
	}
	return (set + 1);
}

#ifdef SETMODE_DEBUG
static void
dumpmode(BITCMD *set)
{
	for (; set->cmd; ++set)
		(void)printf("cmd: '%c' bits %04o%s%s%s%s%s%s\n",
		    set->cmd, set->bits, set->cmd2 ? " cmd2:" : "",
		    set->cmd2 & CMD2_CLR ? " CLR" : "",
		    set->cmd2 & CMD2_SET ? " SET" : "",
		    set->cmd2 & CMD2_UBITS ? " UBITS" : "",
		    set->cmd2 & CMD2_GBITS ? " GBITS" : "",
		    set->cmd2 & CMD2_OBITS ? " OBITS" : "");
}
#endif

/*
 * Given an array of bitcmd structures, compress by compacting consecutive
 * '+', '-' and 'X' commands into at most 3 commands, one of each.  The 'u',
 * 'g' and 'o' commands continue to be separate.  They could probably be
 * compacted, but it's not worth the effort.
 */
static void
compress_mode(BITCMD *set)
{
	BITCMD *nset;
	int setbits, clrbits, Xbits, op;

	for (nset = set;;) {
		/* Copy over any 'u', 'g' and 'o' commands. */
		while ((op = nset->cmd) != '+' && op != '-' && op != 'X') {
			*set++ = *nset++;
			if (!op)
				return;
		}

		for (setbits = clrbits = Xbits = 0;; nset++) {
			if ((op = nset->cmd) == '-') {
				clrbits |= nset->bits;
				setbits &= ~nset->bits;
				Xbits &= ~nset->bits;
			} else if (op == '+') {
				setbits |= nset->bits;
				clrbits &= ~nset->bits;
				Xbits &= ~nset->bits;
			} else if (op == 'X')
				Xbits |= nset->bits & ~setbits;
			else
				break;
		}
		if (clrbits) {
			set->cmd = '-';
			set->cmd2 = 0;
			set->bits = clrbits;
			set++;
		}
		if (setbits) {
			set->cmd = '+';
			set->cmd2 = 0;
			set->bits = setbits;
			set++;
		}
		if (Xbits) {
			set->cmd = 'X';
			set->cmd2 = 0;
			set->bits = Xbits;
			set++;
		}
	}
}
Commit	Line	Data
e9ce8d39 A	1	/*
	2	* Copyright (c) 1989, 1993, 1994
	3	* The Regents of the University of California. All rights reserved.
	4	*
	5	* This code is derived from software contributed to Berkeley by
	6	* Dave Borman at Cray Research, Inc.
	7	*
	8	* Redistribution and use in source and binary forms, with or without
	9	* modification, are permitted provided that the following conditions
	10	* are met:
	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.
e9ce8d39 A	16	* 4. Neither the name of the University nor the names of its contributors
	17	* may be used to endorse or promote products derived from this software
	18	* without specific prior written permission.
	19	*
	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
	24	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	25	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	26	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	27	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	28	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	29	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	30	* SUCH DAMAGE.
	31	*/
	32
5b2abdfb	33	#if defined(LIBC_SCCS) && !defined(lint)
5b2abdfb	34	static char sccsid[] = "@(#)setmode.c 8.2 (Berkeley) 3/25/94";
5b2abdfb	35	#endif /* LIBC_SCCS and not lint */
9385eb3d	36	#include <sys/cdefs.h>
1f2f436a	37	__FBSDID("$FreeBSD: src/lib/libc/gen/setmode.c,v 1.11 2007/01/09 00:27:55 imp Exp $");
e9ce8d39	38
9385eb3d	39	#include "namespace.h"
e9ce8d39 A	40	#include <sys/types.h>
	41	#include <sys/stat.h>
	42
	43	#include <ctype.h>
e9ce8d39 A	44	#include <signal.h>
	45	#include <stddef.h>
	46	#include <stdlib.h>
9385eb3d	47	#include <unistd.h>
e9ce8d39 A	48
	49	#ifdef SETMODE_DEBUG
	50	#include <stdio.h>
	51	#endif
9385eb3d	52	#include "un-namespace.h"
e9ce8d39 A	53
	54	#define SET_LEN 6 /* initial # of bitcmd struct to malloc */
	55	#define SET_LEN_INCR 4 /* # of bitcmd structs to add as needed */
	56
	57	typedef struct bitcmd {
	58	char cmd;
	59	char cmd2;
	60	mode_t bits;
	61	} BITCMD;
	62
	63	#define CMD2_CLR 0x01
	64	#define CMD2_SET 0x02
	65	#define CMD2_GBITS 0x04
	66	#define CMD2_OBITS 0x08
	67	#define CMD2_UBITS 0x10
	68
9385eb3d A	69	static BITCMD addcmd(BITCMD , int, int, int, u_int);
9385eb3d A	70	static void compress_mode(BITCMD *);
e9ce8d39	71	#ifdef SETMODE_DEBUG
9385eb3d	72	static void dumpmode(BITCMD *);
e9ce8d39 A	73	#endif
	74
	75	/*
	76	* Given the old mode and an array of bitcmd structures, apply the operations
	77	* described in the bitcmd structures to the old mode, and return the new mode.
	78	* Note that there is no '=' command; a strict assignment is just a '-' (clear
	79	* bits) followed by a '+' (set bits).
	80	*/
	81	mode_t
1f2f436a	82	getmode(const void *bbox, mode_t omode)
e9ce8d39	83	{
9385eb3d A	84	const BITCMD *set;
9385eb3d A	85	mode_t clrval, newmode, value;
e9ce8d39	86
9385eb3d	87	set = (const BITCMD *)bbox;
e9ce8d39 A	88	newmode = omode;
	89	for (value = 0;; set++)
	90	switch(set->cmd) {
	91	/*
	92	* When copying the user, group or other bits around, we "know"
	93	* where the bits are in the mode so that we can do shifts to
	94	* copy them around. If we don't use shifts, it gets real
	95	* grundgy with lots of single bit checks and bit sets.
	96	*/
	97	case 'u':
	98	value = (newmode & S_IRWXU) >> 6;
	99	goto common;
	100
	101	case 'g':
	102	value = (newmode & S_IRWXG) >> 3;
	103	goto common;
	104
	105	case 'o':
	106	value = newmode & S_IRWXO;
	107	common: if (set->cmd2 & CMD2_CLR) {
	108	clrval =
	109	(set->cmd2 & CMD2_SET) ? S_IRWXO : value;
	110	if (set->cmd2 & CMD2_UBITS)
	111	newmode &= ~((clrval<<6) & set->bits);
	112	if (set->cmd2 & CMD2_GBITS)
	113	newmode &= ~((clrval<<3) & set->bits);
	114	if (set->cmd2 & CMD2_OBITS)
	115	newmode &= ~(clrval & set->bits);
	116	}
	117	if (set->cmd2 & CMD2_SET) {
	118	if (set->cmd2 & CMD2_UBITS)
	119	newmode \|= (value<<6) & set->bits;
	120	if (set->cmd2 & CMD2_GBITS)
	121	newmode \|= (value<<3) & set->bits;
	122	if (set->cmd2 & CMD2_OBITS)
	123	newmode \|= value & set->bits;
	124	}
	125	break;
	126
	127	case '+':
	128	newmode \|= set->bits;
	129	break;
	130
	131	case '-':
	132	newmode &= ~set->bits;
	133	break;
	134
	135	case 'X':
	136	if (omode & (S_IFDIR\|S_IXUSR\|S_IXGRP\|S_IXOTH))
	137	newmode \|= set->bits;
	138	break;
	139
	140	case '\0':
	141	default:
	142	#ifdef SETMODE_DEBUG
	143	(void)printf("getmode:%04o -> %04o\n", omode, newmode);
	144	#endif
	145	return (newmode);
	146	}
	147	}
	148
	149	#define ADDCMD(a, b, c, d) \
	150	if (set >= endset) { \
9385eb3d	151	BITCMD *newset; \
e9ce8d39 A	152	setlen += SET_LEN_INCR; \
e9ce8d39 A	153	newset = realloc(saveset, sizeof(BITCMD) * setlen); \
9385eb3d A	154	if (!newset) { \
	155	if (saveset) \
	156	free(saveset); \
	157	saveset = NULL; \
e9ce8d39	158	return (NULL); \
9385eb3d	159	} \
e9ce8d39 A	160	set = newset + (set - saveset); \
	161	saveset = newset; \
	162	endset = newset + (setlen - 2); \
	163	} \
	164	set = addcmd(set, (a), (b), (c), (d))
	165
	166	#define STANDARD_BITS (S_ISUID\|S_ISGID\|S_IRWXU\|S_IRWXG\|S_IRWXO)
	167
	168	void *
1f2f436a	169	setmode(const char *p)
e9ce8d39	170	{
9385eb3d A	171	int perm, who;
9385eb3d A	172	char op, *ep;
e9ce8d39 A	173	BITCMD set, saveset, *endset;
	174	sigset_t sigset, sigoset;
	175	mode_t mask;
5b2abdfb	176	int equalopdone=0, permXbits, setlen;
9385eb3d	177	long perml;
e9ce8d39 A	178
	179	if (!*p)
	180	return (NULL);
	181
	182	/*
	183	* Get a copy of the mask for the permissions that are mask relative.
	184	* Flip the bits, we want what's not set. Since it's possible that
	185	* the caller is opening files inside a signal handler, protect them
	186	* as best we can.
	187	*/
	188	sigfillset(&sigset);
9385eb3d	189	(void)_sigprocmask(SIG_BLOCK, &sigset, &sigoset);
e9ce8d39 A	190	(void)umask(mask = umask(0));
e9ce8d39 A	191	mask = ~mask;
9385eb3d	192	(void)_sigprocmask(SIG_SETMASK, &sigoset, NULL);
e9ce8d39 A	193
e9ce8d39 A	194	setlen = SET_LEN + 2;
5b2abdfb	195
e9ce8d39 A	196	if ((set = malloc((u_int)(sizeof(BITCMD) * setlen))) == NULL)
	197	return (NULL);
	198	saveset = set;
	199	endset = set + (setlen - 2);
	200
	201	/*
	202	* If an absolute number, get it and return; disallow non-octal digits
	203	* or illegal bits.
	204	*/
5b2abdfb	205	if (isdigit((unsigned char)*p)) {
9385eb3d A	206	perml = strtol(p, &ep, 8);
9385eb3d A	207	if (*ep \|\| perml < 0 \|\| perml & ~(STANDARD_BITS\|S_ISTXT)) {
e9ce8d39 A	208	free(saveset);
	209	return (NULL);
	210	}
9385eb3d	211	perm = (mode_t)perml;
e9ce8d39	212	ADDCMD('=', (STANDARD_BITS\|S_ISTXT), perm, mask);
9385eb3d	213	set->cmd = 0;
e9ce8d39 A	214	return (saveset);
	215	}
	216
	217	/*
	218	* Build list of structures to set/clear/copy bits as described by
	219	* each clause of the symbolic mode.
	220	*/
	221	for (;;) {
	222	/* First, find out which bits might be modified. */
	223	for (who = 0;; ++p) {
	224	switch (*p) {
	225	case 'a':
	226	who \|= STANDARD_BITS;
	227	break;
	228	case 'u':
	229	who \|= S_ISUID\|S_IRWXU;
	230	break;
	231	case 'g':
	232	who \|= S_ISGID\|S_IRWXG;
	233	break;
	234	case 'o':
	235	who \|= S_IRWXO;
	236	break;
	237	default:
	238	goto getop;
	239	}
	240	}
	241
	242	getop: if ((op = *p++) != '+' && op != '-' && op != '=') {
	243	free(saveset);
	244	return (NULL);
	245	}
	246	if (op == '=')
	247	equalopdone = 0;
	248
	249	who &= ~S_ISTXT;
	250	for (perm = 0, permXbits = 0;; ++p) {
	251	switch (*p) {
	252	case 'r':
	253	perm \|= S_IRUSR\|S_IRGRP\|S_IROTH;
	254	break;
	255	case 's':
	256	/* If only "other" bits ignore set-id. */
5b2abdfb	257	if (!who \|\| who & ~S_IRWXO)
e9ce8d39 A	258	perm \|= S_ISUID\|S_ISGID;
	259	break;
	260	case 't':
	261	/* If only "other" bits ignore sticky. */
5b2abdfb	262	if (!who \|\| who & ~S_IRWXO) {
e9ce8d39 A	263	who \|= S_ISTXT;
	264	perm \|= S_ISTXT;
	265	}
	266	break;
	267	case 'w':
	268	perm \|= S_IWUSR\|S_IWGRP\|S_IWOTH;
	269	break;
	270	case 'X':
	271	permXbits = S_IXUSR\|S_IXGRP\|S_IXOTH;
	272	break;
	273	case 'x':
	274	perm \|= S_IXUSR\|S_IXGRP\|S_IXOTH;
	275	break;
	276	case 'u':
	277	case 'g':
	278	case 'o':
	279	/*
	280	* When ever we hit 'u', 'g', or 'o', we have
	281	* to flush out any partial mode that we have,
	282	* and then do the copying of the mode bits.
	283	*/
	284	if (perm) {
	285	ADDCMD(op, who, perm, mask);
	286	perm = 0;
	287	}
	288	if (op == '=')
	289	equalopdone = 1;
	290	if (op == '+' && permXbits) {
	291	ADDCMD('X', who, permXbits, mask);
	292	permXbits = 0;
	293	}
	294	ADDCMD(*p, who, op, mask);
	295	break;
	296
	297	default:
	298	/*
	299	* Add any permissions that we haven't already
	300	* done.
	301	*/
	302	if (perm \|\| (op == '=' && !equalopdone)) {
	303	if (op == '=')
	304	equalopdone = 1;
	305	ADDCMD(op, who, perm, mask);
	306	perm = 0;
	307	}
	308	if (permXbits) {
	309	ADDCMD('X', who, permXbits, mask);
	310	permXbits = 0;
	311	}
	312	goto apply;
	313	}
	314	}
	315
	316	apply: if (!*p)
	317	break;
	318	if (*p != ',')
	319	goto getop;
	320	++p;
	321	}
	322	set->cmd = 0;
	323	#ifdef SETMODE_DEBUG
	324	(void)printf("Before compress_mode()\n");
	325	dumpmode(saveset);
	326	#endif
327	compress_mode(saveset);
328	#ifdef SETMODE_DEBUG
329	(void)printf("After compress_mode()\n");
330	dumpmode(saveset);
331	#endif
332	return (saveset);
333	}
334
335	static BITCMD *
1f2f436a	336	addcmd(BITCMD *set, int op, int who, int oparg, u_int mask)
e9ce8d39 A	337	{
	338	switch (op) {
	339	case '=':
	340	set->cmd = '-';
	341	set->bits = who ? who : STANDARD_BITS;
	342	set++;
	343
	344	op = '+';
	345	/* FALLTHROUGH */
	346	case '+':
	347	case '-':
	348	case 'X':
	349	set->cmd = op;
	350	set->bits = (who ? who : mask) & oparg;
	351	break;
	352
	353	case 'u':
	354	case 'g':
	355	case 'o':
	356	set->cmd = op;
	357	if (who) {
	358	set->cmd2 = ((who & S_IRUSR) ? CMD2_UBITS : 0) \|
	359	((who & S_IRGRP) ? CMD2_GBITS : 0) \|
	360	((who & S_IROTH) ? CMD2_OBITS : 0);
9385eb3d	361	set->bits = (mode_t)~0;
e9ce8d39 A	362	} else {
	363	set->cmd2 = CMD2_UBITS \| CMD2_GBITS \| CMD2_OBITS;
	364	set->bits = mask;
	365	}
5b2abdfb	366
e9ce8d39 A	367	if (oparg == '+')
	368	set->cmd2 \|= CMD2_SET;
	369	else if (oparg == '-')
	370	set->cmd2 \|= CMD2_CLR;
	371	else if (oparg == '=')
	372	set->cmd2 \|= CMD2_SET\|CMD2_CLR;
	373	break;
	374	}
	375	return (set + 1);
	376	}
	377
	378	#ifdef SETMODE_DEBUG
	379	static void
1f2f436a	380	dumpmode(BITCMD *set)
e9ce8d39 A	381	{
	382	for (; set->cmd; ++set)
	383	(void)printf("cmd: '%c' bits %04o%s%s%s%s%s%s\n",
	384	set->cmd, set->bits, set->cmd2 ? " cmd2:" : "",
	385	set->cmd2 & CMD2_CLR ? " CLR" : "",
	386	set->cmd2 & CMD2_SET ? " SET" : "",
	387	set->cmd2 & CMD2_UBITS ? " UBITS" : "",
	388	set->cmd2 & CMD2_GBITS ? " GBITS" : "",
	389	set->cmd2 & CMD2_OBITS ? " OBITS" : "");
	390	}
	391	#endif
	392
	393	/*
	394	* Given an array of bitcmd structures, compress by compacting consecutive
	395	* '+', '-' and 'X' commands into at most 3 commands, one of each. The 'u',
5b2abdfb	396	* 'g' and 'o' commands continue to be separate. They could probably be
e9ce8d39 A	397	* compacted, but it's not worth the effort.
e9ce8d39 A	398	*/
5b2abdfb	399	static void
1f2f436a	400	compress_mode(BITCMD *set)
e9ce8d39	401	{
9385eb3d A	402	BITCMD *nset;
9385eb3d A	403	int setbits, clrbits, Xbits, op;
e9ce8d39 A	404
	405	for (nset = set;;) {
	406	/* Copy over any 'u', 'g' and 'o' commands. */
	407	while ((op = nset->cmd) != '+' && op != '-' && op != 'X') {
	408	set++ = nset++;
	409	if (!op)
	410	return;
	411	}
	412
	413	for (setbits = clrbits = Xbits = 0;; nset++) {
	414	if ((op = nset->cmd) == '-') {
	415	clrbits \|= nset->bits;
	416	setbits &= ~nset->bits;
	417	Xbits &= ~nset->bits;
	418	} else if (op == '+') {
	419	setbits \|= nset->bits;
	420	clrbits &= ~nset->bits;
	421	Xbits &= ~nset->bits;
	422	} else if (op == 'X')
	423	Xbits \|= nset->bits & ~setbits;
	424	else
	425	break;
	426	}
	427	if (clrbits) {
	428	set->cmd = '-';
	429	set->cmd2 = 0;
	430	set->bits = clrbits;
	431	set++;
	432	}
	433	if (setbits) {
	434	set->cmd = '+';
	435	set->cmd2 = 0;
	436	set->bits = setbits;
	437	set++;
	438	}
	439	if (Xbits) {
	440	set->cmd = 'X';
	441	set->cmd2 = 0;
	442	set->bits = Xbits;
	443	set++;
	444	}
	445	}
	446	}