我正在制作一个Winsock应用程序，当它尝试进行关闭功能时，服务器中的某些内容会失败。该项目构建并运行，但是当客户端的第一个连接到达时，它会接受它并在命令行中显示失败： ＆＃34;关机失败，错误：10038＆＃34;。 我一直在阅读有关错误的内容，据说这通常是因为函数关闭应用于不是SOCKET的东西，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;
}
我上传整个项目，以防你想更深入地检查（https://mega.nz/#!dtcx1DCL!dKWV2ryDDfiXv5H3Mi2p4PrBpie2CGrGJOTAwvQAV8M），但问题出在服务器上（我简化了代码），客户端只是为了你可以启动连接输入用户名（但不关心它）。
提前感谢您，我们将不胜感激。
答案 0 :(得分：2)
让我们从您显示的来源中考虑以下几行：
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关闭（很好）。发生这种情况时，请调用closesocket关闭套接字。 但是 然后您继续无条件地在已关闭的套接字上调用shutdown，从而导致出现错误。
简单的解决方案？只需使用closesocket 关闭套接字，就可以看到shutdown，我可以看到（很少有）。