TCP 服务端与客户端

介绍如何使用 libcc 的 TCP API：创建监听事件、accept 新连接、处理读写、以及发起主动连接。

TCP 服务端

服务端示例tests/event.c，简化版。

*** 示例代码（tests/event.c）***

#include <libcc.h>
#include <stdio.h>

static bool_t echo_handler(_cc_async_event_t *async, _cc_event_t *e, const uint32_t which) {
    if (which & _CC_EVENT_ACCEPT_) {
        /* 监听端 accept 会在线程中由 async->accept 执行（见 tests 中完整实现） */
        return true;
    }
    if (which & _CC_EVENT_READABLE_) {
        /* 读取并回显 */
        char buf[1024];
        int32_t r = _cc_recv(e->fd, (byte_t*)buf, sizeof(buf));
        if (r <= 0) return false;
        _cc_send(e->fd, (byte_t*)buf, r);
        return true;
    }
    if (which & _CC_EVENT_CLOSED_) {
        return false;
    }
    return true;
}

int main(void) {
    struct sockaddr_in sa;
    _cc_async_event_t async;
    _cc_event_t *e;

    _cc_install_socket();
    if (!_cc_register_poller(&async)) return -1;

    e = _cc_event_alloc(&async, _CC_EVENT_ACCEPT_);
    e->callback = echo_handler;
    e->timeout = 60000;

    _cc_inet_ipv4_addr(&sa, nullptr, 8081);
    if (!_cc_tcp_listen(&async, e, (_cc_sockaddr_t*)&sa, sizeof(struct sockaddr_in))) {
        _cc_free_event(&async, e);
        return -1;
    }

    while (1) {
        async.wait(&async, 100);
    }
    async.free(&async);
    return 0;
}

TCP 客户端

客户端示例（调用 _cc_tcp_connect，参考 tests/test_tcp_client.c 客户端使用 _cc_event_alloc 创建带有 _CC_EVENT_CONNECT_ 标志的事件，然后调用 _cc_tcp_connect 发起连接，并在回调中处理可读/可写事件。

#include <libcc.h>
#include <stdio.h>

static bool_t echo_handler(_cc_async_event_t *async, _cc_event_t *e, const uint32_t which) {
    if (which & _CC_EVENT_CONNECT_) {
        return true;
    }
    if (which & _CC_EVENT_READABLE_) {
        /* 读取并回显 */
        char buf[1024];
        int32_t r = _cc_recv(e->fd, (byte_t*)buf, sizeof(buf));
        if (r <= 0) return false;
        _cc_send(e->fd, (byte_t*)buf, r);
        return true;
    }
    if (which & _CC_EVENT_CLOSED_) {
        return false;
    }
    return true;
}

int main(void) {
    struct sockaddr_in sa;
    _cc_async_event_t async;
    _cc_event_t *e;

    _cc_install_socket();
    if (!_cc_register_poller(&async)) return -1;

    e = _cc_event_alloc(async, _CC_EVENT_CONNECT_|_CC_EVENT_TIMEOUT_|_CC_EVENT_READABLE_);
    e->callback = echo_handler;
    e->timeout = 60000;

    _cc_inet_ipv4_addr(&sa, nullptr, 8081);
    if (!_cc_tcp_connect(async, event, (_cc_sockaddr_t *)&sa, sizeof(struct sockaddr_in))) {
        _cc_free_event(async, event);
        return false;
    }

    while (1) {
        async.wait(&async, 100);
    }
    async.free(&async);
    return 0;
}