端口映射后socket怎样建立连接

Question

我想通过socket使两台电脑建立连接，两台电脑都处于不同的局域网中，所以要先端口映射。其中一台电脑通过端口映射后的ip地址为180.160.71.130:3389 .
在映射后怎样写socket的关键语句使得两台电脑建立连接呢？

在端口映射之前socket语句是这样的，并且两台电脑在同一个局域网下可以工作:

//服务器
DWORD WINAPI AnswerThread(LPVOID lparam)
{
printf("Thread ID:%4d create!\n", GetCurrentThreadId());
int ret;
char buf[50] = { 0 };
char sendBuf[80] = { 0 };
SOCKET clientSocket = (SOCKET)(LPVOID)lparam;
while (true)
{
memset(buf, 0, sizeof(buf));
ret = recv(clientSocket, buf, sizeof(buf), 0);
if (ret<=0)
{
break;
}
printf("revc: %s\n", buf);
sprintf_s(sendBuf, "Thread ID:%4d revced", GetCurrentThreadId());
ret = send(clientSocket, sendBuf, strlen(sendBuf) + sizeof(char), 0);
if (ret <= 0)
{
break;
}
}
printf("Thread ID:%4d stop!\n", GetCurrentThreadId());
closesocket(clientSocket);
return 1;
}
int _tmain(int argc, _TCHAR* argv[])
{
WORD wVersionRequested;
WSADATA wsaData;
wVersionRequested = MAKEWORD(1, 1);
if (WSAStartup(wVersionRequested, &wsaData) == INVALID_SOCKET)
{
return 0;
}

if (LOBYTE(wsaData.wVersion) != 1 ||
HIBYTE(wsaData.wVersion) != 1) {
WSACleanup();
return 0;
}
SOCKET sockSrv = socket(AF_INET, SOCK_STREAM, 0);
int len = sizeof(SOCKADDR);
SOCKADDR_IN clientAddr;
SOCKADDR_IN serviceAddr;
serviceAddr.sin_addr.S_un.S_addr = htonl(INADDR_ANY);
serviceAddr.sin_family = AF_INET;
serviceAddr.sin_port = htons(8000);

if (bind(sockSrv, (SOCKADDR*)&serviceAddr, len) == INVALID_SOCKET)
{
printf("failed bind!\n");
closesocket(sockSrv);
WSACleanup();
return 0;
}
if (listen(sockSrv, LISTEN_MAX_COUNT) == SOCKET_ERROR) {
printf("Listen failed with error: %ld\n", WSAGetLastError());
closesocket(sockSrv);
WSACleanup();
return 0;
}

SOCKET sockClient;
HANDLE hThread = NULL;
DWORD dwThreadId;
while (1)
{
sockClient = accept(sockSrv, (SOCKADDR*)&clientAddr, &len);

Sleep(1000);
hThread = CreateThread(NULL, NULL, AnswerThread, (LPVOID)sockClient, 0, &dwThreadId);

if (hThread == NULL)
{
    printf("CreatThread AnswerThread() failed.\n");
}

}

closesocket(sockSrv);
WSACleanup();
return 0;
}
客户端 client 代码：

//客户端
int _tmain(int argc, _TCHAR* argv[])
{
WORD wVersionRequested;
WSADATA wsaData;
int err;

wVersionRequested = MAKEWORD(1, 1);
if (WSAStartup(wVersionRequested, &wsaData) == INVALID_SOCKET)
{
return -1;
}

if (LOBYTE(wsaData.wVersion) != 1 ||
HIBYTE(wsaData.wVersion) != 1) {
WSACleanup();
return -1;
}

SOCKET sockClient = socket(AF_INET, SOCK_STREAM, 0);
int len = sizeof(SOCKADDR);

SOCKADDR_IN local;
local.sin_addr.S_un.S_addr = inet_addr("222.66.117.26");
local.sin_family = AF_INET;
local.sin_port = htons(8000);

if (connect(sockClient, (SOCKADDR*)&local, len) == INVALID_SOCKET)
{
printf("connect error/n");
return 0;
}

char inputBuf[30];
char recvBuf[50];
int ret;
// while (scanf_s("%s", inputBuf, sizeof(inputBuf)) != EOF)
while (gets_s(inputBuf))
{
if (strcmp(inputBuf, "stop") ==0)
{
break;
}
ret = send(sockClient, inputBuf, strlen(inputBuf) + sizeof(char), 0);
if (ret<=0)
{
printf("send failed!\n");
break;
}
ret = recv(sockClient, recvBuf, sizeof(recvBuf), 0);
if (ret <= 0)
{
printf("recv failed!\n");
break;
}
printf("my reply is : %s\n", recvBuf);
//printf("%s\n", inet_ntoa(local.sin_addr));
}
closesocket(sockClient);
WSACleanup();
return 0;
}

Answer 1

你想要你的电脑，在外网可以使用你的网络服务，需要做一下花生壳映射，你给的那个ip是你的入网的ip，入网ip说白了同你的电脑发生不了关系，
我曾经就是使用路由器的花生壳功能，将自己的电脑开放到外网去，然后其他电脑就可以访问我的服务器网站了