[apple/file_cmds.git] / chown / chown.c

/*
 * Copyright (c) 1988, 1993, 1994
 *	The Regents of the University of California.  All rights reserved.
 *
 * 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.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 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.
 */

#include <sys/cdefs.h>
#ifndef lint
__used static const char copyright[] =
"@(#) Copyright (c) 1988, 1993, 1994\n\
	The Regents of the University of California.  All rights reserved.\n";
#endif /* not lint */

#ifndef lint
#if 0
static char sccsid[] = "@(#)chown.c	8.8 (Berkeley) 4/4/94";
#endif
#endif /* not lint */

#include <sys/cdefs.h>
__RCSID("$FreeBSD: src/usr.sbin/chown/chown.c,v 1.24 2002/07/17 16:22:24 dwmalone Exp $");

#include <sys/param.h>
#include <sys/stat.h>

#include <err.h>
#include <errno.h>
#include <fts.h>
#include <grp.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/time.h>

#ifdef __APPLE__
#include <get_compat.h>
#else
#define COMPAT_MODE(a,b) (1)
#endif /* __APPLE__ */

void	a_gid(const char *);
void	a_uid(const char *);
void	chownerr(const char *);
static uid_t	id(const char *, const char *);
void	usage(void);

uid_t uid;
gid_t gid;
int ischown;
#ifdef __APPLE__
int isnumeric = 0;
#endif
const char *gname;

int
main(int argc, char **argv)
{
	FTS *ftsp;
	FTSENT *p;
	int Hflag, Lflag, Pflag, Rflag, fflag, hflag, vflag;
	int ch, fts_options, rval;
	char *cp;
	int unix2003_compat = 0;
	int symlink_found = 0;

	if (argc < 1)
		usage();
	cp = strrchr(argv[0], '/');
	cp = (cp != NULL) ? cp + 1 : argv[0];
	ischown = (strcmp(cp, "chown") == 0);

	Hflag = Lflag = Pflag = Rflag = fflag = hflag = vflag = 0;
#ifdef __APPLE__
	while ((ch = getopt(argc, argv, "HLPRfhnv")) != -1)
#else
	while ((ch = getopt(argc, argv, "HLPRfhv")) != -1)
#endif
		switch (ch) {
		case 'H':
			Hflag = 1;
			Lflag = Pflag = 0;
			break;
		case 'L':
			Lflag = 1;
			Hflag = Pflag = 0;
			break;
		case 'P':
			Pflag = 1;
			Hflag = Lflag = 0;
			break;
		case 'R':
			Rflag = 1;
			break;
		case 'f':
			fflag = 1;
			break;
		case 'h':
			hflag = 1;
	 		break;
#ifdef __APPLE__
		case 'n':
			isnumeric = 1;
			break;
#endif
		case 'v':
			vflag = 1;
			break;
		case '?':
		default:
			usage();
		}
	argv += optind;
	argc -= optind;

	if (argc < 2)
		usage();
	if (!Rflag && (Hflag || Lflag || Pflag))
		warnx("options -H, -L, -P only useful with -R");

	if (Rflag) {
		fts_options = FTS_PHYSICAL;
		if (hflag && (Hflag || Lflag))
			errx(1, "the -R%c and -h options may not be "
			    "specified together", Hflag ? 'H' : 'L');
		if (Hflag)
			fts_options |= FTS_COMFOLLOW;
		else if (Lflag) {
			fts_options &= ~FTS_PHYSICAL;
			fts_options |= FTS_LOGICAL;
		}
	} else
		fts_options = hflag ? FTS_PHYSICAL : FTS_LOGICAL;

	uid = (uid_t)-1;
	gid = (gid_t)-1;
	if (ischown) {
		unix2003_compat = COMPAT_MODE("bin/chown", "Unix2003");
		if ((cp = strchr(*argv, ':')) != NULL) {
			*cp++ = '\0';
			a_gid(cp);
		}
#ifdef SUPPORT_DOT
		else if ((cp = strchr(*argv, '.')) != NULL) {
			warnx("separation of user and group with a period is deprecated");
			*cp++ = '\0';
			a_gid(cp);
		}
#endif
		a_uid(*argv);
	} else {
		unix2003_compat = COMPAT_MODE("bin/chgrp", "Unix2003");
		a_gid(*argv);
	}

	if ((ftsp = fts_open(++argv, fts_options, 0)) == NULL)
		err(1, NULL);

	for (rval = 0; (p = fts_read(ftsp)) != NULL;) {
		symlink_found = 0;
		switch (p->fts_info) {
		case FTS_D:			/* Change it at FTS_DP. */
			if (!Rflag)
				fts_set(ftsp, p, FTS_SKIP);
			continue;
		case FTS_DNR:			/* Warn, chown. */
			warnx("%s: %s", p->fts_path, strerror(p->fts_errno));
			rval = 1;
			break;
		case FTS_ERR:			/* Warn, continue. */
		case FTS_NS:
			warnx("%s: %s", p->fts_path, strerror(p->fts_errno));
			rval = 1;
			continue;
		case FTS_SL:
		case FTS_SLNONE:
			/*
			 * The only symlinks that end up here are ones that
			 * don't point to anything and ones that we found
			 * doing a physical walk.
			 */
			if (hflag)
				break;
			else {
				symlink_found = 1;
				if (unix2003_compat) {
					if (Hflag || Lflag) {       /* -H or -L was specified */
						if (p->fts_errno) {
							warnx("%s: %s", p->fts_name, strerror(p->fts_errno));
							rval = 1;
							continue;
						}
					}
					break; /* Otherwise symlinks keep going */
				}
				continue;
			}
		default:
			break;
		}
		if (unix2003_compat) {
			/* Can only avoid updating times if both uid and gid are -1 */
			if ((uid == (uid_t)-1) && (gid == (gid_t)-1))
				continue;
		} else {
			if ((uid == (uid_t)-1 || uid == p->fts_statp->st_uid) &&
			    (gid == (gid_t)-1 || gid == p->fts_statp->st_gid))
				continue;
		}
		if (((hflag || symlink_found) ? lchown : chown)(p->fts_accpath, uid, gid) == -1) {
			if (!fflag) {
				chownerr(p->fts_path);
				rval = 1;
			}
		} else {
			if (vflag)
				printf("%s\n", p->fts_path);
		}
	}
	if (errno)
		err(1, "fts_read");
	exit(rval);
}

void
a_gid(const char *s)
{
	struct group *gr;

	if (*s == '\0')			/* Argument was "uid[:.]". */
		return;
	gname = s;
#ifdef __APPLE__
	gid = (!isnumeric && ((gr = getgrnam(s)) != NULL)) ? gr->gr_gid : id(s, "group");
#else
	gid = ((gr = getgrnam(s)) != NULL) ? gr->gr_gid : id(s, "group");
#endif
}

void
a_uid(const char *s)
{
	struct passwd *pw;

	if (*s == '\0')			/* Argument was "[:.]gid". */
		return;
#ifdef __APPLE__
	uid = (!isnumeric && ((pw = getpwnam(s)) != NULL)) ? pw->pw_uid : id(s, "user");
#else
	uid = ((pw = getpwnam(s)) != NULL) ? pw->pw_uid : id(s, "user");
#endif
}

static uid_t
id(const char *name, const char *type)
{
	unsigned long val;
	char *ep;

	errno = 0;
	val = strtoul(name, &ep, 10);
	if (errno || *ep != '\0' || val > UID_MAX)
		errx(1, "%s: illegal %s name", name, type);
	return (uid_t)val;
}

void
chownerr(const char *file)
{
	static uid_t euid = -1;
	static int ngroups = -1;
	gid_t groups[NGROUPS_MAX];

	/* Check for chown without being root. */
	if (errno != EPERM || (uid != (uid_t)-1 &&
	    euid == (uid_t)-1 && (euid = geteuid()) != 0)) {
		warn("%s", file);
		return;
	}

	/* Check group membership; kernel just returns EPERM. */
	if (gid != (gid_t)-1 && ngroups == -1 &&
	    euid == (uid_t)-1 && (euid = geteuid()) != 0) {
		ngroups = getgroups(NGROUPS_MAX, groups);
		while (--ngroups >= 0 && gid != groups[ngroups]);
		if (ngroups < 0) {
			warnx("you are not a member of group %s", gname);
			return;
		}
	}
	warn("%s", file);
}

void
usage(void)
{

	if (ischown)
		(void)fprintf(stderr, "%s\n%s\n",
#ifdef __APPLE__
		    "usage: chown [-fhnv] [-R [-H | -L | -P]] owner[:group]"
		    " file ...",
		    "       chown [-fhnv] [-R [-H | -L | -P]] :group file ...");
#else
		    "usage: chown [-fhv] [-R [-H | -L | -P]] owner[:group]"
		    " file ...",
		    "       chown [-fhv] [-R [-H | -L | -P]] :group file ...");
#endif
	else
		(void)fprintf(stderr, "%s\n",
#ifdef __APPLE__
		    "usage: chgrp [-fhnv] [-R [-H | -L | -P]] group file ...");
#else
		    "usage: chgrp [-fhv] [-R [-H | -L | -P]] group file ...");
#endif
	exit(1);
}
Commit	Line	Data
44a7a5ab A	1	/*
	2	* Copyright (c) 1988, 1993, 1994
	3	* The Regents of the University of California. All rights reserved.
	4	*
	5	* Redistribution and use in source and binary forms, with or without
	6	* modification, are permitted provided that the following conditions
	7	* are met:
	8	* 1. Redistributions of source code must retain the above copyright
	9	* notice, this list of conditions and the following disclaimer.
	10	* 2. Redistributions in binary form must reproduce the above copyright
	11	* notice, this list of conditions and the following disclaimer in the
	12	* documentation and/or other materials provided with the distribution.
	13	* 3. All advertising materials mentioning features or use of this software
	14	* must display the following acknowledgement:
	15	* This product includes software developed by the University of
	16	* California, Berkeley and its contributors.
	17	* 4. Neither the name of the University nor the names of its contributors
	18	* may be used to endorse or promote products derived from this software
	19	* without specific prior written permission.
	20	*
	21	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	22	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	23	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	24	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	25	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	26	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	27	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	28	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	29	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	30	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	31	* SUCH DAMAGE.
	32	*/
	33
00337e45	34	#include <sys/cdefs.h>
44a7a5ab	35	#ifndef lint
00337e45	36	__used static const char copyright[] =
6c780a1f A	37	"@(#) Copyright (c) 1988, 1993, 1994\n\
6c780a1f A	38	The Regents of the University of California. All rights reserved.\n";
44a7a5ab A	39	#endif /* not lint */
	40
	41	#ifndef lint
	42	#if 0
	43	static char sccsid[] = "@(#)chown.c 8.8 (Berkeley) 4/4/94";
44a7a5ab A	44	#endif
	45	#endif /* not lint */
	46
6c780a1f A	47	#include <sys/cdefs.h>
	48	__RCSID("$FreeBSD: src/usr.sbin/chown/chown.c,v 1.24 2002/07/17 16:22:24 dwmalone Exp $");
	49
44a7a5ab A	50	#include <sys/param.h>
	51	#include <sys/stat.h>
	52
44a7a5ab A	53	#include <err.h>
44a7a5ab A	54	#include <errno.h>
44a7a5ab A	55	#include <fts.h>
	56	#include <grp.h>
	57	#include <pwd.h>
	58	#include <stdio.h>
	59	#include <stdlib.h>
	60	#include <string.h>
	61	#include <unistd.h>
864a4b6e A	62	#include <sys/time.h>
	63
	64	#ifdef __APPLE__
	65	#include <get_compat.h>
	66	#else
	67	#define COMPAT_MODE(a,b) (1)
	68	#endif /* __APPLE__ */
44a7a5ab	69
6c780a1f A	70	void a_gid(const char *);
	71	void a_uid(const char *);
	72	void chownerr(const char *);
4d0bb651	73	static uid_t id(const char , const char );
6c780a1f	74	void usage(void);
44a7a5ab A	75
	76	uid_t uid;
	77	gid_t gid;
6c780a1f	78	int ischown;
48fce603 A	79	#ifdef __APPLE__
	80	int isnumeric = 0;
	81	#endif
6c780a1f	82	const char *gname;
44a7a5ab A	83
44a7a5ab A	84	int
6c780a1f	85	main(int argc, char **argv)
44a7a5ab A	86	{
	87	FTS *ftsp;
	88	FTSENT *p;
40bf83fe	89	int Hflag, Lflag, Pflag, Rflag, fflag, hflag, vflag;
6c780a1f	90	int ch, fts_options, rval;
44a7a5ab	91	char *cp;
864a4b6e A	92	int unix2003_compat = 0;
864a4b6e A	93	int symlink_found = 0;
44a7a5ab	94
864a4b6e A	95	if (argc < 1)
864a4b6e A	96	usage();
6c780a1f A	97	cp = strrchr(argv[0], '/');
	98	cp = (cp != NULL) ? cp + 1 : argv[0];
	99	ischown = (strcmp(cp, "chown") == 0);
	100
40bf83fe	101	Hflag = Lflag = Pflag = Rflag = fflag = hflag = vflag = 0;
48fce603 A	102	#ifdef __APPLE__
	103	while ((ch = getopt(argc, argv, "HLPRfhnv")) != -1)
	104	#else
6c780a1f	105	while ((ch = getopt(argc, argv, "HLPRfhv")) != -1)
48fce603	106	#endif
44a7a5ab A	107	switch (ch) {
	108	case 'H':
	109	Hflag = 1;
40bf83fe	110	Lflag = Pflag = 0;
44a7a5ab A	111	break;
	112	case 'L':
	113	Lflag = 1;
40bf83fe	114	Hflag = Pflag = 0;
44a7a5ab A	115	break;
44a7a5ab A	116	case 'P':
40bf83fe	117	Pflag = 1;
44a7a5ab A	118	Hflag = Lflag = 0;
	119	break;
	120	case 'R':
	121	Rflag = 1;
	122	break;
	123	case 'f':
	124	fflag = 1;
	125	break;
	126	case 'h':
44a7a5ab	127	hflag = 1;
f383e97b	128	break;
48fce603 A	129	#ifdef __APPLE__
	130	case 'n':
	131	isnumeric = 1;
	132	break;
	133	#endif
6c780a1f A	134	case 'v':
	135	vflag = 1;
	136	break;
44a7a5ab A	137	case '?':
	138	default:
	139	usage();
	140	}
	141	argv += optind;
	142	argc -= optind;
	143
	144	if (argc < 2)
	145	usage();
40bf83fe A	146	if (!Rflag && (Hflag \|\| Lflag \|\| Pflag))
40bf83fe A	147	warnx("options -H, -L, -P only useful with -R");
44a7a5ab	148
44a7a5ab	149	if (Rflag) {
6c780a1f A	150	fts_options = FTS_PHYSICAL;
	151	if (hflag && (Hflag \|\| Lflag))
	152	errx(1, "the -R%c and -h options may not be "
	153	"specified together", Hflag ? 'H' : 'L');
44a7a5ab A	154	if (Hflag)
44a7a5ab A	155	fts_options \|= FTS_COMFOLLOW;
6c780a1f	156	else if (Lflag) {
44a7a5ab A	157	fts_options &= ~FTS_PHYSICAL;
	158	fts_options \|= FTS_LOGICAL;
	159	}
6c780a1f A	160	} else
6c780a1f A	161	fts_options = hflag ? FTS_PHYSICAL : FTS_LOGICAL;
44a7a5ab	162
6c780a1f A	163	uid = (uid_t)-1;
6c780a1f A	164	gid = (gid_t)-1;
44a7a5ab	165	if (ischown) {
864a4b6e	166	unix2003_compat = COMPAT_MODE("bin/chown", "Unix2003");
440bd198	167	if ((cp = strchr(*argv, ':')) != NULL) {
44a7a5ab A	168	*cp++ = '\0';
44a7a5ab A	169	a_gid(cp);
440bd198 A	170	}
	171	#ifdef SUPPORT_DOT
	172	else if ((cp = strchr(*argv, '.')) != NULL) {
6c780a1f	173	warnx("separation of user and group with a period is deprecated");
44a7a5ab A	174	*cp++ = '\0';
44a7a5ab A	175	a_gid(cp);
440bd198 A	176	}
440bd198 A	177	#endif
44a7a5ab	178	a_uid(*argv);
864a4b6e A	179	} else {
864a4b6e A	180	unix2003_compat = COMPAT_MODE("bin/chgrp", "Unix2003");
44a7a5ab	181	a_gid(*argv);
864a4b6e	182	}
44a7a5ab A	183
44a7a5ab A	184	if ((ftsp = fts_open(++argv, fts_options, 0)) == NULL)
6c780a1f	185	err(1, NULL);
44a7a5ab A	186
44a7a5ab A	187	for (rval = 0; (p = fts_read(ftsp)) != NULL;) {
864a4b6e	188	symlink_found = 0;
44a7a5ab	189	switch (p->fts_info) {
6c780a1f A	190	case FTS_D: /* Change it at FTS_DP. */
6c780a1f A	191	if (!Rflag)
44a7a5ab A	192	fts_set(ftsp, p, FTS_SKIP);
44a7a5ab A	193	continue;
6c780a1f	194	case FTS_DNR: /* Warn, chown. */
44a7a5ab A	195	warnx("%s: %s", p->fts_path, strerror(p->fts_errno));
	196	rval = 1;
	197	break;
	198	case FTS_ERR: /* Warn, continue. */
	199	case FTS_NS:
	200	warnx("%s: %s", p->fts_path, strerror(p->fts_errno));
	201	rval = 1;
	202	continue;
6c780a1f	203	case FTS_SL:
44a7a5ab A	204	case FTS_SLNONE:
	205	/*
	206	* The only symlinks that end up here are ones that
	207	* don't point to anything and ones that we found
	208	* doing a physical walk.
	209	*/
6c780a1f A	210	if (hflag)
6c780a1f A	211	break;
864a4b6e A	212	else {
	213	symlink_found = 1;
	214	if (unix2003_compat) {
	215	if (Hflag \|\| Lflag) { /* -H or -L was specified */
	216	if (p->fts_errno) {
	217	warnx("%s: %s", p->fts_name, strerror(p->fts_errno));
	218	rval = 1;
	219	continue;
	220	}
	221	}
	222	break; /* Otherwise symlinks keep going */
	223	}
6c780a1f	224	continue;
864a4b6e	225	}
44a7a5ab A	226	default:
	227	break;
	228	}
864a4b6e A	229	if (unix2003_compat) {
	230	/* Can only avoid updating times if both uid and gid are -1 */
	231	if ((uid == (uid_t)-1) && (gid == (gid_t)-1))
	232	continue;
	233	} else {
	234	if ((uid == (uid_t)-1 \|\| uid == p->fts_statp->st_uid) &&
	235	(gid == (gid_t)-1 \|\| gid == p->fts_statp->st_gid))
	236	continue;
	237	}
	238	if (((hflag \|\| symlink_found) ? lchown : chown)(p->fts_accpath, uid, gid) == -1) {
6c780a1f A	239	if (!fflag) {
	240	chownerr(p->fts_path);
	241	rval = 1;
	242	}
	243	} else {
	244	if (vflag)
	245	printf("%s\n", p->fts_path);
44a7a5ab A	246	}
	247	}
	248	if (errno)
	249	err(1, "fts_read");
	250	exit(rval);
	251	}
	252
	253	void
6c780a1f	254	a_gid(const char *s)
44a7a5ab A	255	{
	256	struct group *gr;
	257
	258	if (s == '\0') / Argument was "uid[:.]". */
	259	return;
	260	gname = s;
48fce603 A	261	#ifdef __APPLE__
	262	gid = (!isnumeric && ((gr = getgrnam(s)) != NULL)) ? gr->gr_gid : id(s, "group");
	263	#else
6c780a1f	264	gid = ((gr = getgrnam(s)) != NULL) ? gr->gr_gid : id(s, "group");
48fce603	265	#endif
44a7a5ab A	266	}
	267
	268	void
6c780a1f	269	a_uid(const char *s)
44a7a5ab A	270	{
	271	struct passwd *pw;
	272
	273	if (s == '\0') / Argument was "[:.]gid". */
	274	return;
48fce603 A	275	#ifdef __APPLE__
	276	uid = (!isnumeric && ((pw = getpwnam(s)) != NULL)) ? pw->pw_uid : id(s, "user");
	277	#else
6c780a1f	278	uid = ((pw = getpwnam(s)) != NULL) ? pw->pw_uid : id(s, "user");
48fce603	279	#endif
44a7a5ab A	280	}
44a7a5ab A	281
4d0bb651	282	static uid_t
6c780a1f	283	id(const char name, const char type)
44a7a5ab	284	{
4d0bb651	285	unsigned long val;
44a7a5ab A	286	char *ep;
44a7a5ab A	287
44a7a5ab A	288	errno = 0;
44a7a5ab A	289	val = strtoul(name, &ep, 10);
4d0bb651	290	if (errno \|\| *ep != '\0' \|\| val > UID_MAX)
6c780a1f	291	errx(1, "%s: illegal %s name", name, type);
4d0bb651	292	return (uid_t)val;
44a7a5ab A	293	}
	294
	295	void
6c780a1f	296	chownerr(const char *file)
44a7a5ab	297	{
6c780a1f A	298	static uid_t euid = -1;
	299	static int ngroups = -1;
	300	gid_t groups[NGROUPS_MAX];
	301
	302	/* Check for chown without being root. */
	303	if (errno != EPERM \|\| (uid != (uid_t)-1 &&
	304	euid == (uid_t)-1 && (euid = geteuid()) != 0)) {
	305	warn("%s", file);
	306	return;
	307	}
	308
	309	/* Check group membership; kernel just returns EPERM. */
	310	if (gid != (gid_t)-1 && ngroups == -1 &&
	311	euid == (uid_t)-1 && (euid = geteuid()) != 0) {
	312	ngroups = getgroups(NGROUPS_MAX, groups);
	313	while (--ngroups >= 0 && gid != groups[ngroups]);
	314	if (ngroups < 0) {
	315	warnx("you are not a member of group %s", gname);
	316	return;
	317	}
	318	}
	319	warn("%s", file);
	320	}
	321
	322	void
	323	usage(void)
	324	{
	325
	326	if (ischown)
	327	(void)fprintf(stderr, "%s\n%s\n",
48fce603 A	328	#ifdef __APPLE__
	329	"usage: chown [-fhnv] [-R [-H \| -L \| -P]] owner[:group]"
	330	" file ...",
	331	" chown [-fhnv] [-R [-H \| -L \| -P]] :group file ...");
	332	#else
6c780a1f A	333	"usage: chown [-fhv] [-R [-H \| -L \| -P]] owner[:group]"
	334	" file ...",
	335	" chown [-fhv] [-R [-H \| -L \| -P]] :group file ...");
48fce603	336	#endif
6c780a1f A	337	else
6c780a1f A	338	(void)fprintf(stderr, "%s\n",
48fce603 A	339	#ifdef __APPLE__
	340	"usage: chgrp [-fhnv] [-R [-H \| -L \| -P]] group file ...");
	341	#else
6c780a1f	342	"usage: chgrp [-fhv] [-R [-H \| -L \| -P]] group file ...");
48fce603	343	#endif
44a7a5ab A	344	exit(1);
44a7a5ab A	345	}