1 /** 2 * Copyright(c) 2011 Trusted Logic. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in 12 * the documentation and/or other materials provided with the 13 * distribution. 14 * * Neither the name Trusted Logic nor the names of its 15 * contributors may be used to endorse or promote products derived 16 * from this software without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31 #ifndef __LIB_MUTEX_H__ 32 #define __LIB_MUTEX_H__ 33 34 /** 35 * This libray defines a type of simple non-recursive mutex that can 36 * be statically initialized. The interface is very similar to pthread 37 * mutexes. 38 **/ 39 40 #ifdef WIN32 41 42 #include <windows.h> 43 #include "s_type.h" 44 45 /* Windows API: use a critical section with a state describing 46 whether it has been initialized or not or is being initialized. 47 We use interlocked operations on the state to synchronize between 48 multiple threads competing to initialize the critical section */ 49 typedef struct 50 { 51 volatile uint32_t nInitState; 52 CRITICAL_SECTION sCriticalSection; 53 } 54 LIB_MUTEX; 55 56 #define LIB_MUTEX_WIN32_STATE_UNINITIALIZED 0 57 #define LIB_MUTEX_WIN32_STATE_INITIALIZING 1 58 #define LIB_MUTEX_WIN32_STATE_INITIALIZED 2 59 60 #define LIB_MUTEX_INITIALIZER { 0 } 61 62 #endif /* WIN32 */ 63 64 #ifdef LINUX 65 66 #include <pthread.h> 67 #include "s_type.h" 68 69 /* Linux: directly use a pthread mutex. */ 70 typedef pthread_mutex_t LIB_MUTEX; 71 #define LIB_MUTEX_INITIALIZER PTHREAD_MUTEX_INITIALIZER 72 73 #endif /* LINUX */ 74 75 /** 76 * Initialize a mutex. Note that thie function cannot fail. If there 77 * is not enough resource to initialize the mutex, the implementation 78 * resort to active-wait 79 **/ 80 void libMutexInit(LIB_MUTEX* pMutex); 81 82 /** 83 * Lock the mutex 84 */ 85 void libMutexLock(LIB_MUTEX* pMutex); 86 87 /** 88 * Unlock the mutex 89 */ 90 void libMutexUnlock(LIB_MUTEX* pMutex); 91 92 /** 93 * Destroy the mutex 94 */ 95 void libMutexDestroy(LIB_MUTEX* pMutex); 96 97 #endif /* __LIB_MUTEX_H__ */ 98