mirror of
https://github.com/topjohnwu/ndk-busybox.git
synced 2024-11-25 04:39:48 +00:00
116 lines
3.3 KiB
C
116 lines
3.3 KiB
C
/*
|
|
* initgroups.c - This file is part of the libc-8086/grp package for ELKS,
|
|
* Copyright (C) 1995, 1996 Nat Friedman <ndf@linux.mit.edu>.
|
|
*
|
|
* This library is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU Library General Public
|
|
* License as published by the Free Software Foundation; either
|
|
* version 2 of the License, or (at your option) any later version.
|
|
*
|
|
* This library 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
|
|
* Library General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Library General Public
|
|
* License along with this library; if not, write to the Free
|
|
* Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
|
|
*
|
|
*/
|
|
|
|
#include "busybox.h"
|
|
|
|
#include <unistd.h>
|
|
#include <string.h>
|
|
#include <fcntl.h>
|
|
#include "grp_.h"
|
|
|
|
/*
|
|
* Define GR_SCALE_DYNAMIC if you want grp to dynamically scale its read buffer
|
|
* so that lines of any length can be used. On very very small systems,
|
|
* you may want to leave this undefined becasue it will make the grp functions
|
|
* somewhat larger (because of the inclusion of malloc and the code necessary).
|
|
* On larger systems, you will want to define this, because grp will _not_
|
|
* deal with long lines gracefully (they will be skipped).
|
|
*/
|
|
#undef GR_SCALE_DYNAMIC
|
|
|
|
#ifndef GR_SCALE_DYNAMIC
|
|
/*
|
|
* If scaling is not dynamic, the buffers will be statically allocated, and
|
|
* maximums must be chosen. GR_MAX_LINE_LEN is the maximum number of
|
|
* characters per line in the group file. GR_MAX_MEMBERS is the maximum
|
|
* number of members of any given group.
|
|
*/
|
|
#define GR_MAX_LINE_LEN 128
|
|
/* GR_MAX_MEMBERS = (GR_MAX_LINE_LEN-(24+3+6))/9 */
|
|
#define GR_MAX_MEMBERS 11
|
|
|
|
#endif /* !GR_SCALE_DYNAMIC */
|
|
|
|
|
|
/*
|
|
* Define GR_DYNAMIC_GROUP_LIST to make initgroups() dynamically allocate
|
|
* space for it's GID array before calling setgroups(). This is probably
|
|
* unnecessary scalage, so it's undefined by default.
|
|
*/
|
|
#undef GR_DYNAMIC_GROUP_LIST
|
|
|
|
#ifndef GR_DYNAMIC_GROUP_LIST
|
|
/*
|
|
* GR_MAX_GROUPS is the size of the static array initgroups() uses for
|
|
* its static GID array if GR_DYNAMIC_GROUP_LIST isn't defined.
|
|
*/
|
|
#define GR_MAX_GROUPS 64
|
|
|
|
#endif /* !GR_DYNAMIC_GROUP_LIST */
|
|
|
|
int initgroups(__const char *user, gid_t gid)
|
|
{
|
|
register struct group *group;
|
|
|
|
#ifndef GR_DYNAMIC_GROUP_LIST
|
|
gid_t group_list[GR_MAX_GROUPS];
|
|
#else
|
|
gid_t *group_list = NULL;
|
|
#endif
|
|
register char **tmp_mem;
|
|
int num_groups;
|
|
int grp_fd;
|
|
|
|
|
|
if ((grp_fd = open("/etc/group", O_RDONLY)) < 0)
|
|
return -1;
|
|
|
|
num_groups = 0;
|
|
#ifdef GR_DYNAMIC_GROUP_LIST
|
|
group_list = (gid_t *) realloc(group_list, 1);
|
|
#endif
|
|
group_list[num_groups] = gid;
|
|
#ifndef GR_DYNAMIC_GROUP_LIST
|
|
while (num_groups < GR_MAX_GROUPS &&
|
|
(group = __getgrent(grp_fd)) != NULL)
|
|
#else
|
|
while ((group = __getgrent(grp_fd)) != NULL)
|
|
#endif
|
|
{
|
|
if (group->gr_gid != gid)
|
|
{
|
|
tmp_mem = group->gr_mem;
|
|
while (*tmp_mem != NULL) {
|
|
if (!strcmp(*tmp_mem, user)) {
|
|
num_groups++;
|
|
#ifdef GR_DYNAMIC_GROUP_LIST
|
|
group_list = (gid_t *) realloc(group_list, num_groups *
|
|
sizeof(gid_t *));
|
|
#endif
|
|
group_list[num_groups-1] = group->gr_gid;
|
|
}
|
|
tmp_mem++;
|
|
}
|
|
}
|
|
}
|
|
close(grp_fd);
|
|
return setgroups(num_groups, group_list);
|
|
}
|