C++簡單封裝互斥量
阿新 • • 發佈：2018-11-10
在編寫多執行緒程式中，經常需要遇到多執行緒同步操作，例如操作sqlite3資料庫，寫一個日誌檔案，操作一個連結串列等，只能同時一個執行緒操作，因此需要經常用到互斥鎖。
筆者為了方便使用，採用C++簡單封裝Linux互斥鎖，根據建構函式的引數，可以建立遞迴互斥鎖和非遞迴互斥鎖。
程式碼如下：
CMutex.h
/************************************************************************* > File Name: CMutex.h > Author: KentZhang > Mail:[email protected] > Created Time: Wed 02 Sep 2015 01:49:15 PM CST ************************************************************************/ #ifndef __CMUTEX_H__ #define __CMUTEX_H__ #include <pthread.h> #include <sys/types.h> class CMutex { public: CMutex(bool IsRecursive=false);//預設建立非遞迴互斥鎖 ~CMutex(); bool Lock(); bool UnLock(); bool TryLock(); private: pthread_mutex_t *m_pMutex; }; #endif
CMutex.cpp
/************************************************************************* > File Name: CMutex.cpp > Author: KentZhang > Mail: [email protected] > Created Time: Wed 02 Sep 2015 01:46:36 PM CST ************************************************************************/ //封裝互斥鎖 #include "CMutex.h" #include <errno.h> #include <stdlib.h> #include <stdio.h> #include <string.h> #define DEBUG_ERROR(format,...) do{ printf(""format", FileName:%s, FuncName:%s, LineNum:%d\n",\ ##__VA_ARGS__, __FILE__, __func__, __LINE__);}while(0) CMutex::CMutex(bool IsRecursive) { m_pMutex = new pthread_mutex_t; pthread_mutexattr_t attr; pthread_mutexattr_init(&attr); int nResult = 0; do{ if (IsRecursive) { //設定屬性為可遞迴 nResult = pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE); nResult = 20; if ( 0 != nResult ) { DEBUG_ERROR("pthread_mutexattr_settype() failed:%s", strerror(nResult)); break; } } else { //設定屬性為不可遞迴 nResult = pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_NORMAL); if ( 0 != nResult ) { DEBUG_ERROR("pthread_mutexattr_settype() failed:%s", strerror(nResult)); break; } } nResult = pthread_mutex_init(m_pMutex, &attr); if( 0 != nResult ) { DEBUG_ERROR("pthread_mutexattr_settype() failed:%s", strerror(nResult)); break; } }while(0); } CMutex::~CMutex() { int nResult = pthread_mutex_destroy(m_pMutex); if( nResult != 0 ) { DEBUG_ERROR("CMutex ~CMutex() pthread_mutex_destroy() failed:%s", strerror(nResult)); } if ( m_pMutex != NULL ) delete m_pMutex; } bool CMutex::Lock() { int nResult = pthread_mutex_lock(m_pMutex); if( nResult < 0 ) { DEBUG_ERROR("CMutex lock() pthread_mutex_lock() failed:%s", strerror(nResult)); return false; } return true; } bool CMutex::UnLock() { int nResult = pthread_mutex_unlock(m_pMutex); if ( nResult < 0 ) { DEBUG_ERROR("CMutex unlock() pthread_mutex_unlock() failed:%s", strerror(nResult)); return false; } return true; } bool CMutex::TryLock() { int nResult = pthread_mutex_trylock(m_pMutex); if ( nResult != 0 ) { DEBUG_ERROR("CMutex trylock() pthread_mutex_trylock() failed:%s", strerror(nResult)); return false; } return true; }
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