关机失败，错误 10038

Question

我正在制作一个 Winsock 应用程序，但在尝试执行关机功能时服务器出现故障。该项目构建并运行，但是当客户端的第一个连接到达时，它会使用它并且无法在命令行中显示： “关机失败，错误：10038”。 我一直在阅读有关该错误的信息，据说这通常是因为功能关闭应用于不是 SOCKET 或类似的东西。但是在调试时我看到它显然是一个Socket，所以我不知道该怎么做。

#undef UNICODE

#define WIN32_LEAN_AND_MEAN

#include "stdafx.h"

// Need to link with Ws2_32.lib
#pragma comment (lib, "Ws2_32.lib")
// #pragma comment (lib, "Mswsock.lib")

#define DEFAULT_BUFLEN 512
#define DEFAULT_PORT "27015"
//Function declaration
const std::string currentDateTime();
int __cdecl NewClient(SOCKET ListenSocket, SOCKET ClientSocket, char *recvbuf,  int recvbuflen, int iSendResult, int iResult);
std::string CommandGet(char *recvbuf);
void Login(char *recvbuf);
void print_data(char *recvbuf);
string GetUsername(char *recvbuf);
string GetThirdToken(char *recvbuf);

//Map & Struct creation
struct message{
    static unsigned int last_id;
    unsigned int id;
    std::string baa;
    std::string timestamp;
    message(){};
    message(const std::string& recvbuf_baa,const std::string& a_timestamp) :
    baa(recvbuf_baa), timestamp(a_timestamp), id(++last_id)
  {
  }
};
map<std::string,std::vector<message *> > data;
map<std::string,std::vector<string> > followers;
//Global variables
unsigned int message::last_id = 0;
map<std::string,bool> loggedin;

int __cdecl main(void) 
{
    WSADATA wsaData;
    int iResult;

    SOCKET ListenSocket = INVALID_SOCKET;
    SOCKET ClientSocket = INVALID_SOCKET;

    struct addrinfo *result = NULL;
    struct addrinfo hints;



    int iSendResult=0;
    char recvbuf[DEFAULT_BUFLEN];
    int recvbuflen = DEFAULT_BUFLEN;

    // Initialize Winsock
    iResult = WSAStartup(MAKEWORD(2,2), &wsaData);
    if (iResult != 0) {
        printf("WSAStartup failed with error: %d\n", iResult);
        return 1;
    }

    ZeroMemory(&hints, sizeof(hints));
    hints.ai_family = AF_INET;
    hints.ai_socktype = SOCK_STREAM;
    hints.ai_protocol = IPPROTO_TCP;
    hints.ai_flags = AI_PASSIVE;
    while(true){
        // Resolve the server address and port
        iResult = getaddrinfo(NULL, DEFAULT_PORT, &hints, &result);
        if ( iResult != 0 ) {
            printf("getaddrinfo failed with error: %d\n", iResult);
            WSACleanup();
            return 1;
        }

        // Create a SOCKET for connecting to server
        ListenSocket = socket(result->ai_family, result->ai_socktype, result->ai_protocol);
        if (ListenSocket == INVALID_SOCKET) {
            printf("socket failed with error: %ld\n", WSAGetLastError());
            freeaddrinfo(result);
            WSACleanup();
            return 1;
        }

        // Setup the TCP listening socket
        iResult = ::bind( ListenSocket, result->ai_addr, (int)result->ai_addrlen);
        if (iResult == SOCKET_ERROR) {
            printf("bind failed with error: %d\n", WSAGetLastError());
            freeaddrinfo(result);
            closesocket(ListenSocket);
            WSACleanup();
            return 1;
        }

        freeaddrinfo(result);

        iResult = listen(ListenSocket, SOMAXCONN);
        if (iResult == SOCKET_ERROR) {
            printf("listen failed with error: %d\n", WSAGetLastError());
            closesocket(ListenSocket);
            WSACleanup();
            return 1;
        }
        // Accept a client socket
        ClientSocket = accept(ListenSocket, NULL, NULL);
        if (ClientSocket == INVALID_SOCKET) {
            printf("accept failed with error: %d\n", WSAGetLastError());
            closesocket(ListenSocket);
            WSACleanup();
            return 1;
        }

        // No longer need server socket
        closesocket(ListenSocket);

         return NewClient(ListenSocket, ClientSocket, recvbuf, recvbuflen, iSendResult, iResult);



    }
}

int __cdecl NewClient(SOCKET ListenSocket, SOCKET ClientSocket,  char *recvbuf,  int recvbuflen, int iSendResult, int iResult){



        // Receive until the peer shuts down the connection
        do {
            iResult = recv(ClientSocket, recvbuf, recvbuflen, 0);
            if (iResult > 0) {
                printf("Bytes received: %d\n", iResult);
                std::string cmd=CommandGet(recvbuf);
                if (cmd=="log"){
                    std::string usrn=GetUsername(recvbuf);
                    std::string recvbuf_str="";
                    for(auto it=loggedin.begin();it!=loggedin.end();it++){
                        if ((*it).first==usrn){
                            recvbuf_str="loggedin";
                            if ((*it).second){
                                recvbuf_str="cantlogin";
                                break;
                            }
                            else{
                                loggedin[usrn]=1;
                                break;
                            }
                            break;
                        }
                    }
                    if (recvbuf_str==""){
                        recvbuf_str="newlogin";
                        Login(recvbuf);
                    }
                    iSendResult = send( ClientSocket, recvbuf_str.c_str(), iResult, 0 );
                    if (iSendResult == SOCKET_ERROR) {
                        printf("send failed with error: %d\n", WSAGetLastError());
                        closesocket(ClientSocket);
                        WSACleanup();
                          return 1;
                    }
                }


            }

            else if (iResult == 0){
                printf("Connection closing...\n");
                closesocket(ClientSocket);}
            else  {
                printf("recv failed with error: %d\n", WSAGetLastError());
                closesocket(ClientSocket);
                WSACleanup();
                  return 1;
            }

        } while (iResult > 0);


    // shutdown the connection since we're done
    iResult = shutdown(ClientSocket, SD_SEND);
    if (iResult == SOCKET_ERROR) {
        printf("shutdown failed with error: %d\n", WSAGetLastError());
        closesocket(ClientSocket);
        WSACleanup();
        return 1;
    }

    // cleanup
    closesocket(ClientSocket);
    WSACleanup();

    return 0;
}
const std::string currentDateTime() {
    time_t     now = time(0);
    struct tm  tstruct;
    char       buf[80];
    localtime_s(&tstruct, &now);
    strftime(buf, sizeof(buf), "%Y-%m-%d %X", &tstruct);
    return buf;
}

void Login(char *recvbuf){
    std::string usrn= GetUsername(recvbuf);
    std::vector<message *> messages;
    data[usrn]=messages;
    std::vector<string> follow;
    followers[usrn]=follow;
    loggedin[usrn]=1;
}


void print_data(char *recvbuf){
    std::string usrn= GetUsername(recvbuf);

    for(auto mapIt = data.cbegin(); mapIt != data.cend(); ++mapIt)
    {
    std::cout << "printing data for " << mapIt->first << ":" << std::endl;
    for(auto vectIter = mapIt->second.cbegin(); vectIter != mapIt->second.cend(); ++vectIter)
        {
            std::cout << (*vectIter)->baa << ", " << (*vectIter)->timestamp << ", "
                  << (*vectIter)->id << std::endl;
        }
    }
}

void print_followers(char *recvbuf){
    std::string usrn= GetUsername(recvbuf);

    for(auto mapIt = followers.cbegin(); mapIt != followers.cend(); ++mapIt)
    {
    std::cout << "printing followers for " << mapIt->first << ":" << std::endl;
    for(auto vectIter = mapIt->second.cbegin(); vectIter != mapIt->second.cend(); ++vectIter)
        {
            std::cout << (*vectIter) << endl;
        }
    }
}

std::string CommandGet(char *recvbuf){
        int start0=0;
        std::string recvbuf_cmd;
        std::string recvstr(recvbuf);
        start0=recvstr.find(';');
        recvbuf_cmd=recvstr.substr(0,start0);
        return recvbuf_cmd;
}

string GetUsername(char *recvbuf){
    int start0=0, start1=0;
    std::string recvbuf_usrn;
    std::string recvstr(recvbuf);
    start0=recvstr.find(';');
    start1=recvstr.find(';',start0+1);
    recvbuf_usrn=recvstr.substr(start0+1,start1-start0-1);
    return recvbuf_usrn;
}

string GetThirdToken(char *recvbuf){
    int start0=0, start1=0, start2=0;
    std::string recvbuf_thirdtoken;
    std::string recvstr(recvbuf);
    start0=recvstr.find(';');
    start1=recvstr.find(';',start0+1);
    start2=recvstr.find(';',start1+1);
    recvbuf_thirdtoken=recvstr.substr(start1+1,start2-start1-1);
    return recvbuf_thirdtoken;
}

我上传了整个项目以防你想更深入地检查它（https://mega.nz/#!dtcx1DCL!dKWV2ryDDfiXv5H3Mi2p4PrBpie2CGrGJOTAwvQAV8M），但问题出在服务器上（我简化了代码），客户端只是这样你就可以开始连接进入用户名（但不在乎）。

提前感谢您，任何帮助将不胜感激。

Answer 1

让我们考虑以下几行，取自您显示的来源：

iResult = recv(ClientSocket, recvbuf, recvbuflen, 0);
...
else if (iResult == 0){
    printf("Connection closing...\n");
    closesocket(ClientSocket);}
...
iResult = shutdown(ClientSocket, SD_SEND);

当recv 返回零时，表示连接已被另一端（很好地）关闭。发生这种情况时，您调用closesocket 来关闭套接字。 但是然后你继续在关闭的套接字上无条件地调用shutdown，导致你得到错误。

简单的解决方案？只需使用closesocket 关闭套接字一次，我可以看到这里不需要shutdown（很少有）。