1 /** 2 * Copyright (c) 2013 Larisa Grigore<larisagrigore@gmail.com>. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. The name of the author may not be used to endorse or promote products 14 * derived from this software without specific prior written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28 #ifndef _SYSVIPC_LOCK_H_ 29 #define _SYSVIPC_LOCK_H_ 30 31 #include "sysvipc_lock_generic.h" 32 33 #define SYSV_RWLOCK 34 35 struct sysv_mutex { 36 umtx_t _mutex_static_lock; 37 int pid_owner; 38 int tid_owner; 39 }; 40 41 struct sysv_rwlock { 42 struct sysv_mutex lock; /* monitor lock */ 43 int read_signal; 44 int write_signal; 45 int state; /* 0 = idle >0 = # of readers -1 = writer */ 46 int blocked_writers; 47 }; 48 49 int sysv_mutex_init(struct sysv_mutex *); 50 int sysv_mutex_lock(struct sysv_mutex *); 51 int sysv_mutex_unlock(struct sysv_mutex *); 52 53 int sysv_rwlock_init(struct sysv_rwlock *); 54 int sysv_rwlock_unlock(struct sysv_rwlock *); 55 int sysv_rwlock_wrlock(struct sysv_rwlock *); 56 int sysv_rwlock_rdlock(struct sysv_rwlock *); 57 58 #endif /* !_SYSVIPC_LOCK_H_ */ 59