1 /* 2 * ptw32_cond_check_need_init.c 3 * 4 * Description: 5 * This translation unit implements condition variables and their primitives. 6 * 7 * 8 * -------------------------------------------------------------------------- 9 * 10 * Pthreads-win32 - POSIX Threads Library for Win32 11 * Copyright(C) 1998 John E. Bossom 12 * Copyright(C) 1999,2005 Pthreads-win32 contributors 13 * 14 * Contact Email: rpj (at) callisto.canberra.edu.au 15 * 16 * The current list of contributors is contained 17 * in the file CONTRIBUTORS included with the source 18 * code distribution. The list can also be seen at the 19 * following World Wide Web location: 20 * http://sources.redhat.com/pthreads-win32/contributors.html 21 * 22 * This library is free software; you can redistribute it and/or 23 * modify it under the terms of the GNU Lesser General Public 24 * License as published by the Free Software Foundation; either 25 * version 2 of the License, or (at your option) any later version. 26 * 27 * This library is distributed in the hope that it will be useful, 28 * but WITHOUT ANY WARRANTY; without even the implied warranty of 29 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 30 * Lesser General Public License for more details. 31 * 32 * You should have received a copy of the GNU Lesser General Public 33 * License along with this library in the file COPYING.LIB; 34 * if not, write to the Free Software Foundation, Inc., 35 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA 36 */ 37 38 #include "pthread.h" 39 #include "implement.h" 40 41 42 INLINE int 43 ptw32_cond_check_need_init (pthread_cond_t * cond) 44 { 45 int result = 0; 46 ptw32_mcs_local_node_t node; 47 48 /* 49 * The following guarded test is specifically for statically 50 * initialised condition variables (via PTHREAD_OBJECT_INITIALIZER). 51 */ 52 ptw32_mcs_lock_acquire(&ptw32_cond_test_init_lock, &node); 53 54 /* 55 * We got here possibly under race 56 * conditions. Check again inside the critical section. 57 * If a static cv has been destroyed, the application can 58 * re-initialise it only by calling pthread_cond_init() 59 * explicitly. 60 */ 61 if (*cond == PTHREAD_COND_INITIALIZER) 62 { 63 result = pthread_cond_init (cond, NULL); 64 } 65 else if (*cond == NULL) 66 { 67 /* 68 * The cv has been destroyed while we were waiting to 69 * initialise it, so the operation that caused the 70 * auto-initialisation should fail. 71 */ 72 result = EINVAL; 73 } 74 75 ptw32_mcs_lock_release(&node); 76 77 return result; 78 } 79
