C++插座表现得很奇怪

C++ sockets acting weird

本文关键字:插座 C++      更新时间:2023-10-16

我正在尝试建立一个服务器,但accept()函数有问题。问题是,它接受空连接(我不知道它们来自哪里),并且它还从它们那里接收空的东西。

这是我的服务器.cpp类

#include "Server.h"
#include <thread>
Server::Server()
{
    usercount = 0;
    int RetVal=0;
    WSAData wsaData;
    WORD DllVersion=MAKEWORD(2,1);
    RetVal=WSAStartup(DllVersion,&wsaData);
    if( RetVal != 0 )
    {
        MessageBoxA(NULL,"WinSocket startup failed","Error",MB_OK | MB_ICONERROR );
        exit(1);
    }
}
bool Server::ServerStartUp()
{
sListen  = socket(AF_INET, SOCK_STREAM, NULL);
sConnect = socket(AF_INET, SOCK_STREAM, NULL);
addr.sin_addr.s_addr = inet_addr("192.168.0.100");
addr.sin_port        = htons(69);
addr.sin_family      = AF_INET;
bind(sListen, (SOCKADDR*)&addr,sizeof(addr));
listen(sListen,64);
//  CreateThread(0,0,&Server::ServerThread,0,0,0);
std::thread t1(&Server::ServerThread,this);
t1.join();
return true;
}
void Server::ServerThread()
{
int addrlen = sizeof(addr); 
for(;;Sleep(10))
{
    if( sConnect = accept( sListen, (SOCKADDR*)&addr, &addrlen )) 
    {
        cout << " FUTU ";
        char* UserName = new char[256];
        ZeroMemory(UserName,256);
        recv(sConnect,UserName,256,0);
        char* Password = new char[256];
        ZeroMemory(Password,256);
        recv(sConnect,Password,256,0);

        users[ ++usercount ] = new Client(UserName,Password,sConnect);
        if( users[usercount] ->GetLogInSuccesful() )
            send(sConnect,"0x0001",6,0);
        else
            send(sConnect,"0x0002",6,0);
    }
}
}

还有一个结构几乎完全相同的工作示例,所以我不知道我在哪里做错了什么......

工作示例:

int ReturnValue = 0;
ReturnValue = InitWinSocket();
if(ReturnValue != 0)
{
    MessageBoxA(NULL,"WinSocket startup failed","Error",MB_OK | MB_ICONERROR );
    exit(1);
}
users = new User[64];
sListen  = socket(AF_INET, SOCK_STREAM, NULL);
sConnect = socket(AF_INET, SOCK_STREAM, NULL);
addr.sin_addr.s_addr = inet_addr("192.168.0.100");
addr.sin_port        = htons(1234);
addr.sin_family      = AF_INET;
bind(sListen, (SOCKADDR*)&addr,sizeof(addr));
listen(sListen,64);

int addrlen = sizeof(addr);

for(;;)
{
    if(sConnect = accept(sListen , (SOCKADDR*)&addr,&addrlen))
    {
        int SuccesfulLogIn = 0;
        SuccesfulLogIn = CheckLogInInformation();
        if(SuccesfulLogIn == 0)
        {
            send(sConnect,"0x0002",6,0);
        }
        else
        {
        users[++ConnectionsCounter].UserConnection = sConnect;
        users[ConnectionsCounter].ID = ConnectionsCounter;
        users[ConnectionsCounter].IsUserInGame = false;
        cout<<"Smb Connected";
        send(sConnect,"0x0001",6,0);
        char* Id = new char[20];
        _itoa ( users[ConnectionsCounter].ID,Id,10 );
        send(sConnect,Id,sizeof(Id),0);
        UserThreadHandler[ConnectionsCounter] = CreateThread(0,0,(LPTHREAD_START_ROUTINE)UserThread,(LPVOID)ConnectionsCounter,0,0);
        }
    }
}

在第二个示例中,它只接受正确的连接,并且实际上在点击 accept() 时等待,直到找到连接。

想知道我做错了什么。

因评论而编辑:

发现实际上是我的绑定函数不起作用,我该如何解决这个问题?

我的猜测是,您正在尝试侦听特权端口(低于 1024 的端口),该端口不允许运行程序的用户执行此操作。 bind(), listen(), accept() 等返回指示成功或失败的值 -- 你永远不应该在没有检查这些返回值的情况下调用它们。