mirror of
https://github.com/coreutils/coreutils.git
synced 2024-12-03 23:13:50 +08:00
108 lines
2.7 KiB
C
108 lines
2.7 KiB
C
/* getugroups.c -- return a list of the groups a user is in
|
|
|
|
Copyright (C) 1990, 1991, 1998, 1999, 2000, 2003, 2004, 2005 Free
|
|
Software Foundation.
|
|
|
|
This program is free software; you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation; either version 2, or (at your option)
|
|
any later version.
|
|
|
|
This program is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with this program; if not, write to the Free Software Foundation,
|
|
Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
|
|
|
|
/* Written by David MacKenzie. */
|
|
|
|
#ifdef HAVE_CONFIG_H
|
|
# include <config.h>
|
|
#endif
|
|
|
|
#include <sys/types.h>
|
|
#include <stdio.h> /* grp.h on alpha OSF1 V2.0 uses "FILE *". */
|
|
#include <grp.h>
|
|
|
|
#include <unistd.h>
|
|
|
|
#include <errno.h>
|
|
#ifndef EOVERFLOW
|
|
# define EOVERFLOW EINVAL
|
|
#endif
|
|
|
|
/* setgrent, getgrent, and endgrent are not specified by POSIX.1,
|
|
so header files might not declare them.
|
|
If you don't have them at all, we can't implement this function.
|
|
You lose! */
|
|
struct group *getgrent ();
|
|
|
|
#include <string.h>
|
|
|
|
#define STREQ(s1, s2) ((strcmp (s1, s2) == 0))
|
|
|
|
/* Like `getgroups', but for user USERNAME instead of for the current
|
|
process. Store at most MAXCOUNT group IDs in the GROUPLIST array.
|
|
If GID is not -1, store it first (if possible). GID should be the
|
|
group ID (pw_gid) obtained from getpwuid, in case USERNAME is not
|
|
listed in /etc/groups.
|
|
Always return the number of groups of which USERNAME is a member. */
|
|
|
|
int
|
|
getugroups (int maxcount, GETGROUPS_T *grouplist, char *username, gid_t gid)
|
|
{
|
|
struct group *grp;
|
|
register char **cp;
|
|
register int count = 0;
|
|
|
|
if (gid != (gid_t) -1)
|
|
{
|
|
if (maxcount != 0)
|
|
grouplist[count] = gid;
|
|
++count;
|
|
}
|
|
|
|
setgrent ();
|
|
while ((grp = getgrent ()) != 0)
|
|
{
|
|
for (cp = grp->gr_mem; *cp; ++cp)
|
|
{
|
|
int n;
|
|
|
|
if ( ! STREQ (username, *cp))
|
|
continue;
|
|
|
|
/* See if this group number is already on the list. */
|
|
for (n = 0; n < count; ++n)
|
|
if (grouplist && grouplist[n] == grp->gr_gid)
|
|
break;
|
|
|
|
/* If it's a new group number, then try to add it to the list. */
|
|
if (n == count)
|
|
{
|
|
if (maxcount != 0)
|
|
{
|
|
if (count >= maxcount)
|
|
{
|
|
endgrent ();
|
|
return count;
|
|
}
|
|
grouplist[count] = grp->gr_gid;
|
|
}
|
|
count++;
|
|
if (count < 0)
|
|
{
|
|
errno = EOVERFLOW;
|
|
return -1;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
endgrent ();
|
|
|
|
return count;
|
|
}
|