非套接字上的WINSOCK套接字操作

Question

这是类方法（所有方法和var都声明为公共的）。注意：DiscoverWinsockLib会执行WSAStartup的工作，我知道这部分工作了。 它还会执行LoadLibrary并查找以下功能的DLLs入口点，这些入口已使用lpfn_前缀重命名。

不管我做什么，我似乎都无法解决为什么我在线程中的非套接字上收到套接字操作的错误情况。

任何帮助是极大的赞赏。

bool __fastcall TRANSPORT::Establish (const char *host, int port, int timeout)
{
bool rFlag;
int rval;

rFlag = false;
DiscoverWinsockLib();

if( WSH )
{
    hostEntry = gethostbyname(host);

    if( !hostEntry )
    {
        LastErrorCode = lpfn_WSAGetLastError();
        lpfn_WSACleanup();
        SetErrorMsg();
    }
    else
    {
        CSocket = lpfn_socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);

        if (CSocket == INVALID_SOCKET)
        {
            LastErrorCode = lpfn_WSAGetLastError();
            SetErrorMsg();
            lpfn_WSACleanup();
        }
        else
        {

            RxDataBuf.len = RXDATA_BUFSIZE;
            RxDataBuf.buf = RxBuffer;
            RxOverlapped.hEvent = lpfn_WSACreateEvent();

            if(RxOverlapped.hEvent == WSA_INVALID_EVENT)
            {
                LastErrorCode = lpfn_WSAGetLastError();
                SetErrorMsg();
                SocketShutdown();
                //lpfn_closesocket(CSocket);
            }
            else
            {
                if(lpfn_WSAEventSelect(CSocket, RxOverlapped.hEvent, FD_ALL_EVENTS) == SOCKET_ERROR)
                {
                    LastErrorCode = lpfn_WSAGetLastError();
                    SetErrorMsg();
                    lpfn_closesocket(CSocket);
                    lpfn_WSACloseEvent(RxOverlapped.hEvent);
                }
                else
                {
                    hThreadIO = CreateThread(0, 0, ProcessEvents, (void *)this, 0, &ThreadID);

                    // Try to connect to the server
                    serverInfo.sin_family = AF_INET;
                    serverInfo.sin_addr = *((LPIN_ADDR)*hostEntry->h_addr_list);
                    serverInfo.sin_port = htons(port);

                    if( lpfn_connect(CSocket, (LPSOCKADDR)&serverInfo, sizeof(struct sockaddr)) == SOCKET_ERROR  )
                    {
                        LastErrorCode = lpfn_WSAGetLastError();
                        if( LastErrorCode != WSAEWOULDBLOCK )
                        {
                            SetErrorMsg();
                            SocketShutdown();
                        }
                        else
            rFlag = true;
                    }
                    else
                        rFlag = true;
                }
            }
        }
    }
}
return(rFlag);
}

这是上面引用的线程：

DWORD WINAPI ProcessEvents(void *pParam)
{

TRANSPORT *T;
WSANETWORKEVENTS NetEvents;
DWORD EIndex;
DWORD  rc;
bool Failure;


T = (TRANSPORT *)pParam;
Failure = false;

do
{
    EIndex = T->lpfn_WSAWaitForMultipleEvents( 1, &T->RxOverlapped.hEvent, false, 3000, true );

    if( EIndex == WSA_WAIT_FAILED )
    {
        T->LastErrorCode = T->lpfn_WSAGetLastError();
        T->SetErrorMsg();
        Failure = true;
    }

    if( EIndex == WSA_WAIT_TIMEOUT )
    {
        if( T->OnConnectTimeout )
            T->OnConnectTimeout(T);

        Failure = true;
    }

}while( EIndex != WAIT_IO_COMPLETION && !Failure );

if( Failure )
    return(EIndex);

// Get the event(s) that occurred and their associated error array
if(T->lpfn_WSAEnumNetworkEvents(T->CSocket, T->RxOverlapped.hEvent, &NetEvents) == SOCKET_ERROR)
{
    T->LastErrorCode = T->lpfn_WSAGetLastError();
    T->SetErrorMsg();
    return(EIndex);
}

// =================================================================
// Code above fetches the event that woke this thread up
// Code below deals with the events as they are detected
// =================================================================

if( NetEvents.lNetworkEvents & FD_CONNECT  )
{
    if( T->OnConnect )
        T->OnConnect(T);

    T->lpfn_WSAResetEvent(T->RxOverlapped.hEvent);
}
else if( ( NetEvents.lNetworkEvents & FD_READ) )
{
    rc = T->lpfn_WSARecv(T->CSocket, &T->RxDataBuf, 1, &T->RxBytes, &T->Flags, &T->RxOverlapped, NULL);
    EIndex = T->lpfn_WSAGetLastError();

    if( (rc == SOCKET_ERROR) && (EIndex != WSA_IO_PENDING || EIndex != WSAEWOULDBLOCK ) )
    {
        T->LastErrorCode = EIndex;
        T->SetErrorMsg();
    }
    else
    {
        rc = T->lpfn_WSAWaitForMultipleEvents(1, &T->RxOverlapped.hEvent, true, INFINITE, true);

        if(rc == WSA_WAIT_FAILED)
        {
            T->LastErrorCode = T->lpfn_WSAGetLastError();
            T->SetErrorMsg();
        }
        else
        {
            rc = T->lpfn_WSAGetOverlappedResult(T->CSocket, &T->RxOverlapped, &T->RxBytes, false, &T->Flags);
            if(!rc)
            {
                T->LastErrorCode = T->lpfn_WSAGetLastError();
                T->SetErrorMsg();
            }
            else
            {
                if( T->RxBytes > 0 && T->OnReceive )
                    T->OnReceive(T);

                T->lpfn_WSAResetEvent(T->RxOverlapped.hEvent);
            }
        }
    }
}

return(rc);
}

**更新**我发现对EIndex的调用= T-> lpfn_WSAWaitForMultipleEvents（1，＆T-> RxOverlapped.hEvent，false，3000，true）; 线程函数内部返回WSA_WAIT_FAILED

而且，如果我禁用线程功能并在连接调用之后立即在线程外部检查lpfn_WSAWaitForMultipleEvents的返回值，则将获得有效的WSAEWOULDBLOCK返回值。

考虑到我从线程内部获取地址可能有问题，我将线程代码更改为如下：

DWORD WINAPI ProcessEvents(void *pParam)
{
 ...

WSAEVENT events[1];

T = (TRANSPORT *)pParam;
Failure = false;


do
{
    events[0] = T->RxOverlapped.hEvent;
    EIndex = T->lpfn_WSAWaitForMultipleEvents( 1, events, false, 3000, true );

            ....

而且我仍然无法使WSAWaitForMultipleEvents开心！

有什么想法/建议吗？

Answer 1

如果connect（）失败，则您正在调用SocketShutdown() 。 大概是，它关闭了套接字（您没有显示该代码），但是如果线程正在运行，它会首先终止线程吗？ 否则，您可能要关闭线程背后的套接字。