1/* 2 * initgroups.c - This file is part of the libc-8086/grp package for ELKS, 3 * Copyright (C) 1995, 1996 Nat Friedman <ndf@linux.mit.edu>. 4 * 5 * This library is free software; you can redistribute it and/or 6 * modify it under the terms of the GNU Library General Public 7 * License as published by the Free Software Foundation; either 8 * version 2 of the License, or (at your option) any later version. 9 * 10 * This library is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 * Library General Public License for more details. 14 * 15 * You should have received a copy of the GNU Library General Public 16 * License along with this library; if not, write to the Free 17 * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 18 * 19 */ 20 21#include <unistd.h> 22#include <string.h> 23#include <fcntl.h> 24#include "grp.h" 25#include "config.h" 26 27int initgroups(__const char *user, gid_t gid) 28{ 29 register struct group *group; 30 31#ifndef GR_DYNAMIC_GROUP_LIST 32 gid_t group_list[GR_MAX_GROUPS]; 33#else 34 gid_t *group_list = NULL; 35#endif 36 register char **tmp_mem; 37 int num_groups; 38 int grp_fd; 39 40 41 if ((grp_fd = open("/etc/group", O_RDONLY)) < 0) 42 return -1; 43 44 num_groups = 0; 45#ifdef GR_DYNAMIC_GROUP_LIST 46 group_list = (gid_t *) realloc(group_list, 1); 47#endif 48 group_list[num_groups] = gid; 49#ifndef GR_DYNAMIC_GROUP_LIST 50 while (num_groups < GR_MAX_GROUPS && 51 (group = __getgrent(grp_fd)) != NULL) 52#else 53 while ((group = __getgrent(grp_fd)) != NULL) 54#endif 55 { 56 if (group->gr_gid != gid); 57 { 58 tmp_mem = group->gr_mem; 59 while (*tmp_mem != NULL) { 60 if (!strcmp(*tmp_mem, user)) { 61 num_groups++; 62#ifdef GR_DYNAMIC_GROUP_LIST 63 group_list = (gid_t *) realloc(group_list, num_groups * 64 sizeof(gid_t *)); 65#endif 66 group_list[num_groups] = group->gr_gid; 67 } 68 tmp_mem++; 69 } 70 } 71 } 72 close(grp_fd); 73 return setgroups(num_groups, group_list); 74} 75