NetBSD/lib/libc/gen/getgrouplist.c

113 lines
3.2 KiB
C

/* $NetBSD: getgrouplist.c,v 1.17 2003/08/07 16:42:49 agc Exp $ */
/*
* Copyright (c) 1991, 1993
* 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. 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>
#if defined(LIBC_SCCS) && !defined(lint)
#if 0
static char sccsid[] = "@(#)getgrouplist.c 8.2 (Berkeley) 12/8/94";
#else
__RCSID("$NetBSD: getgrouplist.c,v 1.17 2003/08/07 16:42:49 agc Exp $");
#endif
#endif /* LIBC_SCCS and not lint */
/*
* get credential
*/
#include "namespace.h"
#include <sys/param.h>
#include <assert.h>
#include <grp.h>
#include <string.h>
#include <unistd.h>
#ifdef __weak_alias
__weak_alias(getgrouplist,_getgrouplist)
#endif
/*
* _getgrent_user() is a libc-private function defined in getgrent.c which
* use because certain name service types such as Hesiod lookup grouplists
* by username rather than just iterating over the list of groups.
*/
struct group *_getgrent_user(const char *);
int
getgrouplist(uname, agroup, groups, grpcnt)
const char *uname;
gid_t agroup;
gid_t *groups;
int *grpcnt;
{
struct group *grp;
int i, ngroups;
int ret, maxgroups;
_DIAGASSERT(uname != NULL);
_DIAGASSERT(groups != NULL);
_DIAGASSERT(grpcnt != NULL);
ret = 0;
ngroups = 0;
maxgroups = *grpcnt;
/*
* install primary group
*/
if (ngroups < maxgroups)
groups[ngroups] = agroup;
else
ret = -1;
ngroups++;
/*
* Scan the group file to find additional groups.
*/
setgrent();
nextgroup:
while ((grp = _getgrent_user(uname)) != NULL) {
if (grp->gr_gid == agroup)
continue;
for (i = 0; i < MIN(ngroups, maxgroups); i++) {
if (grp->gr_gid == groups[i])
goto nextgroup;
}
if (ngroups < maxgroups)
groups[ngroups] = grp->gr_gid;
else
ret = -1;
ngroups++;
}
endgrent();
*grpcnt = ngroups;
return (ret);
}