/* * Copyright (c) 2008 Jakub Jermar * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * - Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * - Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * - The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ /** @addtogroup libc * @{ */ /** * @file * @brief This file contains rwlock API and provides its fake * implementation based on futexes. */ #ifndef LIBC_RWLOCK_H_ #define LIBC_RWLOCK_H_ #include #include #include typedef atomic_t rwlock_t; #define RWLOCK_INITIALIZE(rwlock) \ rwlock_t rwlock = FUTEX_INITIALIZER #define rwlock_initialize(rwlock) futex_initialize((rwlock), 1) #define rwlock_read_lock(rwlock) futex_down((rwlock)) #define rwlock_write_lock(rwlock) futex_down((rwlock)) #define rwlock_read_unlock(rwlock) futex_up((rwlock)) #define rwlock_write_unlock(rwlock) futex_up((rwlock)) #endif /** @} */