C - Mongoose 库回复消息

Question

我的代码有问题，但它是对的!但是当我插入一个错误的地址时我会这样做:例如 http://127.0.0.1:27017/this_is_a_try 我的服务器回复我一条消息“这是一次尝试”而不是“错误 404”未找到”。有这么难吗？谢谢大家帮助我。

#include <signal.h>
#include <stdlib.h>
#include "mongoose.h"
static int s_received_signal = 0;
static struct mg_server *s_server = NULL;
static const char *s_remote_addr = "glosbe.com:80";
static void signal_handler(int sig_num) {
    signal(sig_num, signal_handler);
    s_received_signal = sig_num;
}
static int ev_handler(struct mg_connection *conn, enum mg_event ev) {
    struct mg_connection *client, *orig;
    switch (ev) {
    case MG_AUTH:
        return MG_TRUE;
    case MG_CONNECT:
// Send request to the remote host.
// TODO(lsm): handle connect error here.
        mg_printf(conn, "GET %s HTTP/1.0\r\nHost: %s\r\n\r\n",
                "/gapi/translate?from=eng&dest=fra&format=json&phrase=cat",
                s_remote_addr);
        return MG_TRUE;
    case MG_REPLY:
// Send reply to the original connection
        orig = (struct mg_connection *) conn->connection_param;
        mg_send_header(orig, "Content-Type", "text/plain");
        mg_send_data(orig, conn->content, conn->content_len);
        mg_send_data(orig, "", 0); // Last chunk: mark the end of reply
// Disconnect connections
        orig->connection_param = NULL;
        conn->connection_param = NULL;
        return MG_TRUE;
    case MG_REQUEST:
        if ((client = mg_connect(s_server, s_remote_addr)) != NULL) {
// Interconnect requests
            client->connection_param = conn;
            conn->connection_param = client;
            return MG_MORE;
        } else {
            mg_printf_data(conn, "%s", "cannot send API request");
            return MG_TRUE;
        }
    default:
        return MG_FALSE;
    }
}
int main(void) {
    s_server = mg_create_server(NULL, ev_handler);
    mg_set_option(s_server, "listening_port", "27017");
// Setup signal handlers
    signal(SIGTERM, signal_handler);
    signal(SIGINT, signal_handler);
    printf("Listening on port %s\n", mg_get_option(s_server, "listening_port"));
    while (s_received_signal == 0) {
        mg_poll_server(s_server, 1000);
    }
    mg_destroy_server(&s_server);
    printf("Existing on signal %d\n", s_received_signal);
    return EXIT_SUCCESS;
}

Answer 1

您的代码似乎非常接近 mongoose http_client.c样本。

无论如何阅读 mongoose 代码，似乎 http 应答代码填充了 uri 字段。
在 mongoose.c parse_http_message 使用以下代码处理 HTTP 请求和应答:

  ri->request_method = skip(&buf, " ");
  ri->uri = skip(&buf, " ");
  ri->http_version = skip(&buf, "\r\n");

然后它给出机会使用:

mg_send_status(orig, atoi(conn->uri)); // uri contains status response

然后答案代码会变成这样:

case MG_REPLY:
    orig = (struct mg_connection *) conn->connection_param;
    mg_send_status(orig, atoi(conn->uri)); // uri contains status of the http response
    mg_send_header(orig, "Content-Type", "text/plain");
    mg_send_data(orig, conn->content, conn->content_len);
    mg_send_data(orig, "", 0); // Last chunk: mark the end of reply
    orig->connection_param = NULL;
    conn->connection_param = NULL;
    return MG_TRUE;

编辑由于这个commit可以以更明确的方式访问 http 客户端应答代码:

mg_send_status(orig, conn->status_code);