libevent websocket c代码

以下一个使用libevent实现websocket服务端的简单代码示例：

#include <event2/event.h>
#include <event2/http.h>
#include <event2/http_struct.h>
#include <event2/buffer.h>
#include <event2/keyvalq_struct.h>
#include <event2/websocket.h>
#include <event2/listener.h>

static void websocket_handler(struct evhttp_request *req, void *arg) {
    struct evhttp_connection *conn = evhttp_request_get_connection(req);
    struct bufferevent *bev = evhttp_connection_get_bufferevent(conn);
    struct evhttp_uri *uri = evhttp_uri_parse(evhttp_request_get_uri(req));
    const char *path = evhttp_uri_get_path(uri);
    if (strcmp(path, "/websocket") != 0) {
        evhttp_send_error(req, HTTP_BADREQUEST, "Bad Request");
        return;
    }
    struct evkeyvalq headers;
    evhttp_headers_copy(evhttp_request_get_input_headers(req), &headers);
    const char *sec_websocket_key = evhttp_find_header(&headers, "Sec-WebSocket-Key");
    char response_key[29];
    evutil_base64_encode(sec_websocket_key, strlen(sec_websocket_key), response_key, sizeof(response_key));
    evhttp_add_header(evhttp_request_get_output_headers(req), "Sec-WebSocket-Accept", response_key);
    evhttp_add_header(evhttp_request_get_output_headers(req), "Connection", "Upgrade");
    evhttp_add_header(evhttp_request_get_output_headers(req), "Upgrade", "websocket");
    evhttp_send_reply(req, HTTP_SWITCHING_PROTOCOLS, "Switching Protocols", NULL);
    struct websocket *ws = websocket_new(bev);
    websocket_start(ws);
    evhttp_uri_free(uri);
}

int main(int argc, char **argv) {
    struct event_base *base;
    struct evhttp *http;
    struct evhttp_bound_socket *handle;
    struct evhttp_request *req;
    struct evhttp_connection *conn;
    struct event *ev;
    base = event_base_new();
    http = evhttp_new(base);
    evhttp_set_cb(http, "/websocket", websocket_handler, NULL);
    handle = evhttp_bind_socket_with_handle(http, "0.0.0.0", 8080);
    event_base_dispatch(base);
    return 0;
}

这个代码示例使用libevent库实现了一个简单的websocket服务端，监听本地8080端口，当有客户端请求连接时，会发送一个握手响应，建立websocket连接。你可以根据自己的需求，修改相应的代码实现更复杂的功能。