共享内存加锁互斥访问

在做项目时遇到需要用到多个进程对共享内存读写，考虑到数据冲突问题，特加上互斥作为访问约束条件，具体代码如下：

HANDLE CreateOpenFileMapping(LPCTSTR lpShareMemName){//打开共享的文件对象。 HANDLE hMapFile = OpenFileMapping(FILE_MAP_ALL_ACCESS, FALSE,lpShareMemName); if (hMapFile)  {}else{ //创建共享文件。 hMapFile = CreateFileMapping(INVALID_HANDLE_VALUE,NULL, PAGE_READWRITE,0,BUF_SIZE,lpShareMemName); } return hMapFile;}//向共享内存写入数据////////////////////////////////////////////////////////函数主要对共享内存读写///hMapFile :共享内训映射句柄///bInOutData:写入或者读取数据///lpMutexName:互斥量名字///bRW :读写标志 0 read ; 1 write///返回值 ture成功 ;false 失败/////////////////////////////////////////////////////BOOL OperateData(HANDLE hMapFile,BYTE *bInOutData,LPCTSTR lpMutexName,bool bRW){BOOL bSuc = FALSE;BYTE *pBuf = (BYTE *)MapViewOfFile(hMapFile,            // 共享内存的句柄FILE_MAP_ALL_ACCESS, // 可读写许可0,0,BUF_SIZE);if (pBuf){//加把锁在这地方HANDLE hMutex = CreateMutex(NULL,FALSE,lpMutexName);if (hMutex && WaitForSingleObject(hMutex, 30*1000) == WAIT_OBJECT_0){if (bRW){memset(pBuf,0,BUF_SIZE);memcpy(pBuf,bInOutData,BUF_SIZE - 1);} else{memcpy(bInOutData,pBuf,BUF_SIZE - 1);} ReleaseMutex(hMutex);CloseHandle(hMutex);UnmapViewOfFile(pBuf);hMutex = NULL;pBuf = NULL;bSuc = TRUE;}}return bSuc;}//读取共享内存数据BOOL ReadFromMen(HANDLE hMapFile,BYTE *bOutData,LPCTSTR lpMutexName){BOOL bSuc = FALSE;BYTE *pBuf = (BYTE *)MapViewOfFile(hMapFile,            // 共享内存的句柄FILE_MAP_ALL_ACCESS, // 可读写许可0,0,BUF_SIZE);if (pBuf){//加把锁在这地方HANDLE hMutex = CreateMutex(NULL,FALSE,lpMutexName);if (hMutex && WaitForSingleObject(hMutex, 30*1000) == WAIT_OBJECT_0){ReleaseMutex(hMutex);CloseHandle(hMutex);UnmapViewOfFile(pBuf);hMutex = NULL;pBuf = NULL;bSuc = TRUE;}}return bSuc;}wchar_t *MultToWide(LPSTR pChar){wchar_t* pWCHAR=NULL;//计算pChar所指向的多字节字符串相当于多少个宽字节DWORD num=MultiByteToWideChar(CP_ACP,0,pChar,-1,NULL,0);pWCHAR=(wchar_t*)malloc(num*sizeof(wchar_t));if (pWCHAR==NULL){free(pWCHAR);}memset(pWCHAR,0,num*sizeof(wchar_t));//多字节转换为宽字节MultiByteToWideChar(CP_ACP,0,pChar,-1,pWCHAR,num);return pWCHAR;}char *WideToMult(LPWSTR pWCHAR){//计算需要多少个字节才能表示对应的多字节字符串DWORD num=WideCharToMultiByte(CP_ACP,0,pWCHAR,-1,NULL,0,NULL,0);//开辟空间char *pChar=NULL;pChar=(char*)malloc(num*sizeof(char));if (pChar){memset(pChar,0,num*sizeof(char));//将宽字节字符串转换为多字节字符串WideCharToMultiByte(CP_ACP,0,pWCHAR,-1,pChar,num,NULL,0);}return pChar;}int _tmain(){//// 创建共享文件句柄//HANDLE hMapFile = CreateFileMapping(// INVALID_HANDLE_VALUE,    // 物理文件句柄// NULL,                    // 默认安全级别// PAGE_READWRITE,          // 可读可写// 0,                       // 高位文件大小// BUF_SIZE,                // 地位文件大小// szName                   // 共享内存名称// );//char *pBuf = (char *)MapViewOfFile(// hMapFile,            // 共享内存的句柄// FILE_MAP_ALL_ACCESS, // 可读写许可// 0,// 0,// BUF_SIZE// );//while(1)//{// cout << "input..." << endl;// char szInfo[BUF_SIZE] = {0};// gets(szInfo); // 其实gets并不安全// strncpy(pBuf, szInfo, BUF_SIZE - 1);// pBuf[BUF_SIZE - 1] = '\0';//}//UnmapViewOfFile(pBuf);//CloseHandle(hMapFile);//////////写入HANDLE hMapFile = CreateOpenFileMapping(_T("NameOfMappingObject"));for (int i=0;i<1000000;i++){CString strInput = _T("");strInput.Format(_T("%d%d%d%d%d%d;"),i,i,i,i,i,i);char *bInOutData = WideToMult(strInput.GetBuffer(NULL));BOOL Suc = OperateData(hMapFile,(BYTE*)bInOutData,_T("NameOfMappingObjectMutex"),1);cout<<bInOutData<<endl;delete []bInOutData;bInOutData = NULL;}//////////读取数据//for (int i=1;i>0;i++)//{// HANDLE hMapFile1 = CreateOpenFileMapping(_T("NameOfMappingObject"));// BYTE bOutData[1024];// BOOL  Suc = OperateData(hMapFile1,(BYTE*)bOutData,_T("NameOfMappingObjectMutex"),0);// char *P = (char*)bOutData;// cout<<P<<endl;// wchar_t *pWchar = MultToWide(P);// CString strOut = pWchar;// delete []pWchar;// pWchar = NULL;// Sleep(100);//}return 0;}