IOCP WSASend遇到的奇怪问题?

[songxz]

我写了一个IOCP类，用WSASend发送数据,通过

		BOOL isOK = GetQueuedCompletionStatus(
			hCompletionPort,
			&dwTrans,
			(LPDWORD) &lpClientContext,
			&lpOverlapped, INFINITE);

获取发送结果。发现有 dwTrans > lpOverlapped->m_wsabuf.len并且lpOverlapped->m_wsabuf.len == 0的情况出现。dwTrans 一般与原来发送的数据长度（lpOverlapped->m_wsabuf.len）相等。问题是lpOverlapped->m_wsabuf.len == 0这是什么原因引起的？另外数据是发送成功还是没有成功呢？

请高手指点。

[songxz]

没有重复发送，Overlapped关联的是发送，不是接收

[liye378]

是不是 由于多次发送出现的原因啊？
我才刚刚接触IOCP。。下面是一段IOCP的代码，英文注释你看看。。

 while (TRUE)
     {
       // 完成端口有消息来了 
        if  (GetQueuedCompletionStatus(CompletionPort,  & BytesTransferred,(LPDWORD) & PerHandleData, (LPOVERLAPPED  * )  & PerIoData, INFINITE)  ==   0 )
        {
          printf( " GetQueuedCompletionStatus failed with error %d\n " , GetLastError());
          return   0 ;
		} 
 
       // 是不是有人退出了 
 
       if  (BytesTransferred  ==   0 )
        {
         printf( " Closing socket %d\n " , PerHandleData -> Socket);

          if  (closesocket(PerHandleData -> Socket)  ==  SOCKET_ERROR)
           {
            printf( " closesocket() failed with error %d\n " , WSAGetLastError());
             return   0 ;
         } 
 
         GlobalFree(PerHandleData);
         GlobalFree(PerIoData);
          continue ;
      } 
 
       //
 
       if  (PerIoData -> BytesRECV  ==   0 )
       {
         PerIoData -> BytesRECV  =  BytesTransferred;
         PerIoData -> BytesSEND  =   0 ;
	   } 
       else 
       {
         PerIoData -> BytesSEND  +=  BytesTransferred;
	   } 
 
       if  (PerIoData -> BytesRECV  >  PerIoData -> BytesSEND)
       {

          //  Post another WSASend() request.
          //  Since WSASend() is not gauranteed to send all of the bytes requested,
          //  continue posting WSASend() calls until all received bytes are sent. 
         ZeroMemory( & (PerIoData -> Overlapped),  sizeof (OVERLAPPED));
         PerIoData -> DataBuf.buf  =  PerIoData -> Buffer  +  PerIoData -> BytesSEND;
         PerIoData -> DataBuf.len  =  PerIoData -> BytesRECV  -  PerIoData -> BytesSEND;
          if  (WSASend(PerHandleData -> Socket,  & (PerIoData -> DataBuf),  1 ,  & SendBytes,  0 ,
             & (PerIoData -> Overlapped), NULL)  ==  SOCKET_ERROR)
          {
             if  (WSAGetLastError()  !=  ERROR_IO_PENDING)
             {
                printf( " WSASend() failed with error %d\n " , WSAGetLastError());
                return   0 ;
			 } 
		  } 
	   } 
       else 
        {
         PerIoData -> BytesRECV  =   0 ;

          //  Now that there are no more bytes to send post another WSARecv() request. 
 
         Flags  =   0 ;
         ZeroMemory( & (PerIoData -> Overlapped),  sizeof (OVERLAPPED));

         PerIoData -> DataBuf.len  =  DATA_BUFSIZE;
         PerIoData -> DataBuf.buf  =  PerIoData -> Buffer;

          if  (WSARecv(PerHandleData -> Socket,  & (PerIoData -> DataBuf),  1 ,  & RecvBytes,  & Flags, & (PerIoData -> Overlapped), NULL)  ==  SOCKET_ERROR)
          {
             if  (WSAGetLastError()  !=  ERROR_IO_PENDING)
             {
                printf( " WSARecv() failed with error %d\n " , WSAGetLastError());
                return   0 ;
			 } 
		  } 
       } 
   } 

[Eleven]

你的lpOverlapped关联的Overlapped关联的确定是发送，不是接收？？

[mscrack]

内存访问断点, 看谁改了m_wsabuf.len, 应该就知道怎么回事了

[songxz]

原因找到啦，是我发送数据处理有问题。结贴啦，参与的都有分！