/* * pthread_rwlock_unlock.c * * Description: * This translation unit implements read/write lock primitives. * * -------------------------------------------------------------------------- * * Pthreads4w - POSIX Threads Library for Win32 * Copyright(C) 1998 John E. Bossom * Copyright(C) 1999-2018, Pthreads4w contributors * * Homepage: https://sourceforge.net/projects/pthreads4w/ * * The current list of contributors is contained * in the file CONTRIBUTORS included with the source * code distribution. The list can also be seen at the * following World Wide Web location: * https://sourceforge.net/p/pthreads4w/wiki/Contributors/ * * This file is part of Pthreads4w. * * Pthreads4w 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 3 of the License, or * (at your option) any later version. * * Pthreads4w 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 Pthreads4w. If not, see . * */ #ifdef HAVE_CONFIG_H # include #endif #include #include "pthread.h" #include "implement.h" int pthread_rwlock_unlock (pthread_rwlock_t * rwlock) { int result, result1; pthread_rwlock_t rwl; if (rwlock == NULL || *rwlock == NULL) { return (EINVAL); } if (*rwlock == PTHREAD_RWLOCK_INITIALIZER) { /* * Assume any race condition here is harmless. */ return 0; } rwl = *rwlock; if (rwl->nMagic != PTW32_RWLOCK_MAGIC) { return EINVAL; } if (rwl->nExclusiveAccessCount == 0) { if ((result = pthread_mutex_lock (&(rwl->mtxSharedAccessCompleted))) != 0) { return result; } if (++rwl->nCompletedSharedAccessCount == 0) { result = pthread_cond_signal (&(rwl->cndSharedAccessCompleted)); } result1 = pthread_mutex_unlock (&(rwl->mtxSharedAccessCompleted)); } else { rwl->nExclusiveAccessCount--; result = pthread_mutex_unlock (&(rwl->mtxSharedAccessCompleted)); result1 = pthread_mutex_unlock (&(rwl->mtxExclusiveAccess)); } return ((result != 0) ? result : result1); }