版权声明:本文为博主原创文章,未经博主允许不得转载。 https://blog.csdn.net/KentZhang_/article/details/48180865
在编写多线程程序中,经常需要遇到多线程同步操作,例如操作sqlite3数据库,写一个日志文件,操作一个链表等,只能同时一个线程操作,因此需要经常用到互斥锁。
笔者为了方便使用,采用C++简单封装Linux互斥锁,根据构造函数的参数,可以创建递归互斥锁和非递归互斥锁。
代码如下:
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);//默认创建非递归互斥锁
~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
************************************************************************/
//封装互斥锁
#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)
{
//设置属性为可递归
nResult = pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE);
nResult = 20;
if ( 0 != nResult )
{
DEBUG_ERROR("pthread_mutexattr_settype() failed:%s", strerror(nResult));
break;
}
}
else
{
//设置属性为不可递归
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;
}
由于笔者的水平有限,出错在所难免,恳请读者拍砖指正,谢谢阅读。