libcurl - HTTP Request

1#include <curl/curl.h>
2#include <string.h>
3 
4struct response {
5    char *data;
6    size_t size;
7};
8 
9static size_t write_callback(void *contents, size_t size,
10                             size_t nmemb, void *userp)
11{
12    size_t realsize = size * nmemb;
13    struct response *resp = (struct response *)userp;
14 
15    char *ptr = realloc(resp->data, resp->size + realsize + 1);
16    if (!ptr) return 0;
17 
18    resp->data = ptr;
19    memcpy(&(resp->data[resp->size]), contents, realsize);
20    resp->size += realsize;
21    resp->data[resp->size] = '\0';
22 
23    return realsize;
24}
25 
26int http_get(const char *url, struct response *resp)
27{
28    CURL *curl = curl_easy_init();
29    if (!curl) return -1;
30 
31    resp->data = malloc(1);
32    resp->size = 0;
33 
34    curl_easy_setopt(curl, CURLOPT_URL, url);
35    curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_callback);
36    curl_easy_setopt(curl, CURLOPT_WRITEDATA, resp);
37 
38    CURLcode res = curl_easy_perform(curl);
39    curl_easy_cleanup(curl);
40 
41    return (res == CURLE_OK) ? 0 : -1;
42}