如何使用客户端套接字绑定

我正在编写一个套接字库，但在绑定到特定地址和端口的客户端套接字时遇到了一些问题。我目前正在测试我的 winsock TCP 库，尽管我确信没有理由在 *nix 上不会出现同样的问题。到目前为止，一切正常（如果我connect()没有先打电话给bind()我可以send()和recv()）。

我有一个服务器在监听 192.168.1.99：XXXX（我的机器地址）。

然后我得到一个套接字并绑定到 192.168.1.99：0。尝试连接时出现套接字错误 10049 （WSAEADDRNOTAVAIL）。如果我尝试绑定到 0.0.0.0：0，也会发生同样的事情。

如果我尝试绑定到 127.0.0.1：0 或本地主机或保留主机名 NULL（如果可能的话，我应该使用 AI_PASSIVE 标志吗？）然后连接，我会得到 10061 （ WSACONNREFUSED ）。

有人知道在这里这样做的正确方法吗？

EDIT3：事实证明，问题是我在调用绑定之前调用套接字，然后在调用连接之前再次调用它。在调用绑定之前，我将其切换为仅呼叫套接字。我不知道是否有其他人对整个概念感到困惑，所以我会把它留在这里，除非有人觉得它应该关闭？

编辑2：我调用套接字两次的问题吗？

编辑：这是一些功能

int main() {
    WSADATA wsaData;   // if this doesn't work
    if(WSAStartup(MAKEWORD(2,0), &wsaData) != 0) {
        cout << WSAStartup failed << endl;
        return -1;
    }
    ClientSocket* cs = new ClientSocket("192.168.1.99", "XXXX");
    cs->bind("", "0"); //error 10049 (WSAEADDRNOTAVAIL)
    //cs->bind("", "60000"); //error 10049 (WSAEADDRNOTAVAIL)
    //cs->bind("0.0.0.0", "0"); //error 10049 (WSAEADDRNOTAVAIL)
    //cs->bind("0.0.0.0", "60000"); //error 10049 (WSAEADDRNOTAVAIL)
    //cs->bind("192.168.1.99", "0"); //error 10061 (WSACONNREFUSED)
    //cs->bind("192.168.1.99", "60000"); //error 10061 (WSACONNREFUSED)
    //cs->bind("127.0.0.1", "0"); //error 10061 (WSACONNREFUSED)
    //cs->bind("127.0.0.1", "60000"); //error 10061 (WSACONNREFUSED)
    //cs->bind("localhost", "0"); //error 10061 (WSACONNREFUSED)
    //cs->bind("localhost", "60000"); //error 10061 (WSACONNREFUSED)

    cs->connect(); //connects to the info passed in ctor
    Socket* s = cs->getSocket();
    if(s == NULL) {
        cs->close();
        return -1;
    }
    .
    .
    .
    .
}
//these are the methods exposed by my API
int ClientSocket::bind(std::string hostname, std::string port) {
    if(bound) {
        return -1;
    }
    if(connected) {
        return -2;
    }
    //this defines what specialSockOp will do
    ssop = &ClientSocket::BaseDef::bind;
    info->hostname = hostname;
    if(hostname.compare("") == 0) {
        info->AI_FLAG_PASSIVE = true;
    }
    info->port = port;
    //calls SpecialSocket::socket()
    socket();
    bound = true;
    return 0;
}
int ClientSocket::connect() {
    if(connected) {
        return SOCKET_ERROR;
        //throw exception
    }
    if(bound) {
        ssop = &ClientSocket::BaseDef::connect;
    }
    socket();
    return 0;
}
void SpecialSocket::WinImp::socket() {
    struct addrinfo *results = NULL, *p = NULL, hints;
    int rv;
    ZeroMemory(&hints, sizeof(hints));
    hints.ai_family = (containerClass->info->ipType == IP_DUAL ? AF_UNSPEC :
        containerClass->info->ipType == IPV6 ? AF_INET6 : AF_INET);
    hints.ai_socktype = (containerClass->info->protocol == TCP ? SOCK_STREAM : 
        SOCK_DGRAM);
    hints.ai_protocol = 0;
    if(containerClass->info->AI_FLAG_PASSIVE) {
        hints.ai_flags |= AI_PASSIVE;
    }
    if(containerClass->info->AI_FLAG_CANONNAME) {
        hints.ai_flags |= AI_CANONNAME;
    }
    //cStringHostname returns NULL if an empty string has been passed in
    if((rv = getaddrinfo(containerClass->info->cStringHostname(),
         containerClass->info->cStringPort(), &hints, &results)) != 0) {
            //throw exception
    }
    for(p = results; p != NULL; p = p->ai_next) {
        if((containerClass->info->sock_fd = ::socket(p->ai_family,
                 p->ai_socktype, p->ai_protocol)) == INVALID_SOCKET) {
            closesocket(containerClass->info->sock_fd);
            continue;
        }
        //for a ClientSocket specialSockOp will call either bind or connect
        //corresponding to the function called by ClientSocket
        if(containerClass->specialSockOp(p->ai_addr) == SOCKET_ERROR) {
            closesocket(containerClass->info->sock_fd);
            continue;
        }
        break; //successfully connected
    }
    if(p == NULL) {
        //none of the connections in results were good
        //throw exception - could not connect
    }
    freeaddrinfo(results);
}
int SpecialSocket::WinImp::bind(const void* addr) {
    struct sockaddr* ai_addr = (struct sockaddr*)addr;
    return ::bind(containerClass->getSockFd(), ai_addr, sizeof(*ai_addr));
}
int ClientSocket::WinImp::connect(const void* addr) {
    struct sockaddr* ai_addr = (struct sockaddr*)addr;
    int result = ::connect(containerClass->getSockFd(), ai_addr, sizeof(*ai_addr));
    if(result == SOCKET_ERROR) {
        //these are where my errors are showing up
        cout << "error after connect() is - " << WSAGetLastError() << endl;
        return SOCKET_ERROR;
    }
    containerClass->servInfo->sock_fd = containerClass->getSockFd();
    //I separated the functionality here - Socket can only send/recv
    containerClass->s = new Socket();
    //I use getpeername here to get information about the remote socket
    //Long story but basically sets up the Socket
    containerClass->initRWSocket(containerClass->s, containerClass->servInfo);
    return result;
}

然后，用户可以调用ClientSocket.getSocket()，这将返回一个Socket，然后他们可以send/recv该。在我的例子中，这是返回NULL，因为Socket永远不会实例化，因为SpecialSocket::connect在它这样做之前返回。