/* * grent.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. * */ /* * setgrent(), endgrent(), and getgrent() are mutually-dependent functions, * so they are all included in the same object file, and thus all linked * in together. */ #include <features.h> #include <unistd.h> #include <fcntl.h> #include <paths.h> #include "config.h" #ifdef __UCLIBC_HAS_THREADS__ #include <pthread.h> static pthread_mutex_t mylock = PTHREAD_MUTEX_INITIALIZER; # define LOCK pthread_mutex_lock(&mylock) # define UNLOCK pthread_mutex_unlock(&mylock); #else # define LOCK # define UNLOCK #endif #ifdef __UCLIBC_HAS_THREADS__ #include <pthread.h> extern pthread_mutex_t __getgrent_lock; # define GRENT_LOCK pthread_mutex_lock(&__getgrent_lock) # define GRENT_UNLOCK pthread_mutex_unlock(&__getgrent_lock); #else # define GRENT_LOCK # define GRENT_UNLOCK #endif static int grp_fd = -1; static char *line_buff = NULL; static char **members = NULL; void setgrent(void) { LOCK; if (grp_fd != -1) close(grp_fd); grp_fd = open(_PATH_GROUP, O_RDONLY); UNLOCK; } void endgrent(void) { LOCK; if (grp_fd != -1) close(grp_fd); grp_fd = -1; UNLOCK; } struct group *getgrent(void) { struct group *r; LOCK; if (grp_fd == -1) { UNLOCK; return NULL; } UNLOCK; GRENT_LOCK; r = __getgrent(grp_fd, line_buff, members); GRENT_UNLOCK; return r; }