mongoose/examples/http-client/main.c
Sergio R. Caprile 95f44246bf
fix old comment
2023-03-29 11:46:40 -03:00

73 lines
3.0 KiB
C

// Copyright (c) 2021 Cesanta Software Limited
// All rights reserved
//
// Example HTTP client. Connect to `s_url`, send request, wait for a response,
// print the response and exit.
// You can change `s_url` from the command line by executing: ./example YOUR_URL
//
// To enable SSL/TLS, , see https://mongoose.ws/tutorials/tls/#how-to-build
#include "mongoose.h"
// The very first web page in history. You can replace it from command line
static const char *s_url = "http://info.cern.ch/";
static const char *s_post_data = NULL; // POST data
static const uint64_t s_timeout_ms = 1500; // Connect timeout in milliseconds
// Print HTTP response and signal that we're done
static void fn(struct mg_connection *c, int ev, void *ev_data, void *fn_data) {
if (ev == MG_EV_OPEN) {
// Connection created. Store connect expiration time in c->data
*(uint64_t *) c->data = mg_millis() + s_timeout_ms;
} else if (ev == MG_EV_POLL) {
if (mg_millis() > *(uint64_t *) c->data &&
(c->is_connecting || c->is_resolving)) {
mg_error(c, "Connect timeout");
}
} else if (ev == MG_EV_CONNECT) {
// Connected to server. Extract host name from URL
struct mg_str host = mg_url_host(s_url);
// If s_url is https://, tell client connection to use TLS
if (mg_url_is_ssl(s_url)) {
struct mg_tls_opts opts = {.ca = "ca.pem", .srvname = host};
mg_tls_init(c, &opts);
}
// Send request
int content_length = s_post_data ? strlen(s_post_data) : 0;
mg_printf(c,
"%s %s HTTP/1.0\r\n"
"Host: %.*s\r\n"
"Content-Type: octet-stream\r\n"
"Content-Length: %d\r\n"
"\r\n",
s_post_data ? "POST" : "GET", mg_url_uri(s_url), (int) host.len,
host.ptr, content_length);
mg_send(c, s_post_data, content_length);
} else if (ev == MG_EV_HTTP_MSG) {
// Response is received. Print it
struct mg_http_message *hm = (struct mg_http_message *) ev_data;
printf("%.*s", (int) hm->message.len, hm->message.ptr);
c->is_closing = 1; // Tell mongoose to close this connection
*(bool *) fn_data = true; // Tell event loop to stop
} else if (ev == MG_EV_ERROR) {
*(bool *) fn_data = true; // Error, tell event loop to stop
}
}
int main(int argc, char *argv[]) {
const char *log_level = getenv("LOG_LEVEL"); // Allow user to set log level
if (log_level == NULL) log_level = "4"; // Default is verbose
struct mg_mgr mgr; // Event manager
bool done = false; // Event handler flips it to true
if (argc > 1) s_url = argv[1]; // Use URL provided in the command line
mg_log_set(atoi(log_level)); // Set to 0 to disable debug
mg_mgr_init(&mgr); // Initialise event manager
mg_http_connect(&mgr, s_url, fn, &done); // Create client connection
while (!done) mg_mgr_poll(&mgr, 50); // Event manager loops until 'done'
mg_mgr_free(&mgr); // Free resources
return 0;
}