1/* 2 * Copyright (C) 2012 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17/* 18 * Encapsulate a mutex for thread synchronization. 19 */ 20 21#include "Mutex.h" 22#include "NfcJniUtil.h" 23 24#include <cutils/log.h> 25#include <errno.h> 26#include <string.h> 27 28/******************************************************************************* 29** 30** Function: Mutex 31** 32** Description: Initialize member variables. 33** 34** Returns: None. 35** 36*******************************************************************************/ 37Mutex::Mutex () 38{ 39 memset (&mMutex, 0, sizeof(mMutex)); 40 int res = pthread_mutex_init (&mMutex, NULL); 41 if (res != 0) 42 { 43 ALOGE ("Mutex::Mutex: fail init; error=0x%X", res); 44 } 45} 46 47 48/******************************************************************************* 49** 50** Function: ~Mutex 51** 52** Description: Cleanup all resources. 53** 54** Returns: None. 55** 56*******************************************************************************/ 57Mutex::~Mutex () 58{ 59 int res = pthread_mutex_destroy (&mMutex); 60 if (res != 0) 61 { 62 ALOGE ("Mutex::~Mutex: fail destroy; error=0x%X", res); 63 } 64} 65 66 67/******************************************************************************* 68** 69** Function: lock 70** 71** Description: Block the thread and try lock the mutex. 72** 73** Returns: None. 74** 75*******************************************************************************/ 76void Mutex::lock () 77{ 78 int res = pthread_mutex_lock (&mMutex); 79 if (res != 0) 80 { 81 ALOGE ("Mutex::lock: fail lock; error=0x%X", res); 82 } 83} 84 85 86/******************************************************************************* 87** 88** Function: unlock 89** 90** Description: Unlock a mutex to unblock a thread. 91** 92** Returns: None. 93** 94*******************************************************************************/ 95void Mutex::unlock () 96{ 97 int res = pthread_mutex_unlock (&mMutex); 98 if (res != 0) 99 { 100 ALOGE ("Mutex::unlock: fail unlock; error=0x%X", res); 101 } 102} 103 104 105/******************************************************************************* 106** 107** Function: tryLock 108** 109** Description: Try to lock the mutex. 110** 111** Returns: True if the mutex is locked. 112** 113*******************************************************************************/ 114bool Mutex::tryLock () 115{ 116 int res = pthread_mutex_trylock (&mMutex); 117 if ((res != 0) && (res != EBUSY)) 118 { 119 ALOGE ("Mutex::tryLock: error=0x%X", res); 120 } 121 return res == 0; 122} 123 124 125/******************************************************************************* 126** 127** Function: nativeHandle 128** 129** Description: Get the handle of the mutex. 130** 131** Returns: Handle of the mutex. 132** 133*******************************************************************************/ 134pthread_mutex_t* Mutex::nativeHandle () 135{ 136 return &mMutex; 137} 138 139 140