c++中实现websocket生产端和服务端

在C++中，可以使用第三方库来实现WebSocket生产端和服务端。常用的WebSocket库有：libwebsockets、uWebSockets和Boost.Beast等。

以下是使用libwebsockets库实现WebSocket生产端和服务端的示例代码：

WebSocket服务端：

#include <libwebsockets.h>
#include <string.h>

static int callback_echo(struct libwebsocket_context *context,
                         struct libwebsocket *wsi,
                         enum libwebsocket_callback_reasons reason,
                         void *user, void *in, size_t len)
{
    switch (reason) {
        case LWS_CALLBACK_ESTABLISHED:
            printf("Connection established\n");
            break;

        case LWS_CALLBACK_RECEIVE:
            // 从客户端接收到消息
            printf("Received message: %s\n", (char *) in);

            // 回复消息给客户端
            libwebsocket_write(wsi, (unsigned char *) in, strlen((char *) in), LWS_WRITE_TEXT);
            break;

        default:
            break;
    }

    return 0;
}

int main(int argc, char **argv)
{
    struct libwebsocket_context *context;
    struct libwebsocket_protocols protocols[] = {
            { "echo-protocol", callback_echo, 0 },
            { NULL, NULL, 0 }
    };

    struct lws_context_creation_info info;
    memset(&info, 0, sizeof info);
    info.port = 9000;
    info.protocols = protocols;

    context = libwebsocket_create_context(&info);
    if (context == NULL) {
        printf("Could not create WebSocket context\n");
        return 1;
    }

    printf("WebSocket server started\n");

    while (1) {
        libwebsocket_service(context, 50);
    }

    libwebsocket_context_destroy(context);
    return 0;
}

WebSocket生产端：

#include <libwebsockets.h>
#include <string.h>

static void connect_callback(struct libwebsocket_context *context,
                             struct libwebsocket *wsi,
                             enum libwebsocket_callback_reasons reason,
                             void *user, void *in, size_t len)
{
    if (reason == LWS_CALLBACK_CLIENT_CONNECTION_ERROR) {
        printf("Connection failed\n");
        exit(1);
    }

    if (reason == LWS_CALLBACK_CLIENT_ESTABLISHED) {
        printf("Connection established\n");

        // 发送消息给服务端
        char *message = "Hello, WebSocket server!";
        libwebsocket_write(wsi, (unsigned char *) message, strlen(message), LWS_WRITE_TEXT);
    }
}

int main(int argc, char **argv)
{
    struct lws_context_creation_info info;
    memset(&info, 0, sizeof info);
    info.port = CONTEXT_PORT_NO_LISTEN;
    info.protocols = NULL;

    struct libwebsocket_context *context = libwebsocket_create_context(&info);
    if (context == NULL) {
        printf("Could not create WebSocket context\n");
        return 1;
    }

    struct libwebsocket *wsi = libwebsocket_client_connect(context, "localhost", 9000,
                                                           0, "/", "localhost", NULL, NULL, -1);
    if (wsi == NULL) {
        printf("Could not connect to WebSocket server\n");
        return 1;
    }

    printf("Connecting to WebSocket server...\n");

    while (1) {
        libwebsocket_service(context, 50);
    }

    libwebsocket_context_destroy(context);
    return 0;
}

注意：以上示例代码仅供参考，实际使用时需要根据具体需求进行修改。