Running the Winsock Client and Server Code Sample

àì夳堔傛蜴生んèń 2022-09-10 05:09 123阅读 0赞

This section contains the complete source code for the TCP/IP Client and Server applications:

*  [Complete Winsock Client Code][]
 *  [Complete Winsock Server Code][]

The server application should be started before the client application is started.

To execute the server, compile the complete server source code and run the executable file. The server application listens on TCP port 27015 for a client to connect. Once a client connects, the server receives data from the client and echoes (sends) the data received back to the client. When the client shuts down the connection, the server shuts down the client socket, closes the socket, and exits.

To execute the client, compile the complete client source code and run the executable file. The client application requires that name of the computer or IP address of the computer where the server application is running is passed as a command-line parameter when the client is executed. If the client and server are executed on the sample computer, the client can be started as follows:

**client localhost**

The client tries to connect to the server on TCP port 27015. Once the client connects, the client sends data to the server and receives any data send back from the server. The client then closes the socket and exits.

# Complete Winsock Server Code #

The following is the complete source code for the basic Winsock TCP/IP Server application.

### Winsock Server Source Code ###

\#undef UNICODE

\#define WIN32\_LEAN\_AND\_MEAN

\#include <windows.h>  
\#include <winsock2.h>  
\#include <ws2tcpip.h>  
\#include <stdlib.h>  
\#include <stdio.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"

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;  
    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;

// 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);

// Receive until the peer shuts down the connection  
    do \{

iResult = recv(ClientSocket, recvbuf, recvbuflen, 0);  
        if (iResult > 0) \{  
            printf("Bytes received: %d\\n", iResult);

// Echo the buffer back to the sender  
            iSendResult = send( ClientSocket, recvbuf, iResult, 0 );  
            if (iSendResult == SOCKET\_ERROR) \{  
                printf("send failed with error: %d\\n", WSAGetLastError());  
                closesocket(ClientSocket);  
                WSACleanup();  
                return 1;  
            \}  
            printf("Bytes sent: %d\\n", iSendResult);  
        \}  
        else if (iResult == 0)  
            printf("Connection closing...\\n");  
        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;  
\}

# Complete Winsock Client Code #

The following is the complete source code for the basic Winsock TCP/IP Client Application.

### Winsock Client Source Code ###

\#define WIN32\_LEAN\_AND\_MEAN

\#include <windows.h>  
\#include <winsock2.h>  
\#include <ws2tcpip.h>  
\#include <stdlib.h>  
\#include <stdio.h>

// Need to link with Ws2\_32.lib, Mswsock.lib, and Advapi32.lib  
\#pragma comment (lib, "Ws2\_32.lib")  
\#pragma comment (lib, "Mswsock.lib")  
\#pragma comment (lib, "AdvApi32.lib")

\#define DEFAULT\_BUFLEN 512  
\#define DEFAULT\_PORT "27015"

int \_\_cdecl main(int argc, char \*\*argv)  
\{  
    WSADATA wsaData;  
    SOCKET ConnectSocket = INVALID\_SOCKET;  
    struct addrinfo \*result = NULL,  
                    \*ptr = NULL,  
                    hints;  
    char \*sendbuf = "this is a test";  
    char recvbuf\[DEFAULT\_BUFLEN\];  
    int iResult;  
    int recvbuflen = DEFAULT\_BUFLEN;  
     
    // Validate the parameters  
    if (argc != 2) \{  
        printf("usage: %s server-name\\n", argv\[0\]);  
        return 1;  
    \}

// 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\_UNSPEC;  
    hints.ai\_socktype = SOCK\_STREAM;  
    hints.ai\_protocol = IPPROTO\_TCP;

// Resolve the server address and port  
    iResult = getaddrinfo(argv\[1\], DEFAULT\_PORT, &hints, &result);  
    if ( iResult != 0 ) \{  
        printf("getaddrinfo failed with error: %d\\n", iResult);  
        WSACleanup();  
        return 1;  
    \}

// Attempt to connect to an address until one succeeds  
    for(ptr=result; ptr != NULL ;ptr=ptr->ai\_next) \{

// Create a SOCKET for connecting to server  
        ConnectSocket = socket(ptr->ai\_family, ptr->ai\_socktype,  
            ptr->ai\_protocol);  
        if (ConnectSocket == INVALID\_SOCKET) \{  
            printf("socket failed with error: %ld\\n", WSAGetLastError());  
            WSACleanup();  
            return 1;  
        \}

// Connect to server.  
        iResult = connect( ConnectSocket, ptr->ai\_addr, (int)ptr->ai\_addrlen);  
        if (iResult == SOCKET\_ERROR) \{  
            closesocket(ConnectSocket);  
            ConnectSocket = INVALID\_SOCKET;  
            continue;  
        \}  
        break;  
    \}

freeaddrinfo(result);

if (ConnectSocket == INVALID\_SOCKET) \{  
        printf("Unable to connect to server!\\n");  
        WSACleanup();  
        return 1;  
    \}

// Send an initial buffer  
    iResult = send( ConnectSocket, sendbuf, (int)strlen(sendbuf), 0 );  
    if (iResult == SOCKET\_ERROR) \{  
        printf("send failed with error: %d\\n", WSAGetLastError());  
        closesocket(ConnectSocket);  
        WSACleanup();  
        return 1;  
    \}

printf("Bytes Sent: %ld\\n", iResult);

// shutdown the connection since no more data will be sent  
    iResult = shutdown(ConnectSocket, SD\_SEND);  
    if (iResult == SOCKET\_ERROR) \{  
        printf("shutdown failed with error: %d\\n", WSAGetLastError());  
        closesocket(ConnectSocket);  
        WSACleanup();  
        return 1;  
    \}

// Receive until the peer closes the connection  
    do \{

iResult = recv(ConnectSocket, recvbuf, recvbuflen, 0);  
        if ( iResult > 0 )  
            printf("Bytes received: %d\\n", iResult);  
        else if ( iResult == 0 )  
            printf("Connection closed\\n");  
        else  
            printf("recv failed with error: %d\\n", WSAGetLastError());

\} while( iResult > 0 );

// cleanup  
    closesocket(ConnectSocket);  
    WSACleanup();

return 0;  
\}

[Complete Winsock Client Code]: http://msdn.microsoft.com/en-us/library/windows/desktop/ms737591%28v=vs.85%29.aspx
[Complete Winsock Server Code]: http://msdn.microsoft.com/en-us/library/windows/desktop/ms737593%28v=vs.85%29.aspx