curl/docs/examples/threaded-ssl.c
Jay Satiro fd2315e5ae examples/threaded-ssl: remove locking callback code
- Remove the locking callback code that demonstrates how to meet
  requirements of threading libraries (mainly OpenSSL).

Locking callback code has not been needed for many years. According to
the documentation for OpenSSL and GnuTLS they are thread-safe by design,
assuming support for the underlying OS threading API is built-in.

Ref: https://github.com/curl/curl/pull/13850#issuecomment-2143538458

Closes https://github.com/curl/curl/pull/13851
2024-06-04 13:00:21 -04:00

100 lines
3.2 KiB
C

/***************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
*
* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
* are also available at https://curl.se/docs/copyright.html.
*
* You may opt to use, copy, modify, merge, publish, distribute and/or sell
* copies of the Software, and permit persons to whom the Software is
* furnished to do so, under the terms of the COPYING file.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
* SPDX-License-Identifier: curl
*
***************************************************************************/
/* <DESC>
* Show the required mutex callback setups for GnuTLS and OpenSSL when using
* libcurl multi-threaded.
* </DESC>
*/
/* A multi-threaded example that uses pthreads and fetches 4 remote files at
* once over HTTPS.
*
* Recent versions of OpenSSL and GnuTLS are thread safe by design, assuming
* support for the underlying OS threading API is built-in. Older revisions
* of this example demonstrated locking callbacks for the SSL library, which
* are no longer necessary. An older revision with callbacks can be found at
* https://github.com/curl/curl/blob/curl-7_88_1/docs/examples/threaded-ssl.c
*/
#define USE_OPENSSL /* or USE_GNUTLS accordingly */
#include <stdio.h>
#include <pthread.h>
#include <curl/curl.h>
#define NUMT 4
/* List of URLs to fetch.*/
const char * const urls[]= {
"https://www.example.com/",
"https://www2.example.com/",
"https://www3.example.com/",
"https://www4.example.com/",
};
static void *pull_one_url(void *url)
{
CURL *curl;
curl = curl_easy_init();
curl_easy_setopt(curl, CURLOPT_URL, url);
/* this example does not verify the server's certificate, which means we
might be downloading stuff from an impostor */
curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 0L);
curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 0L);
curl_easy_perform(curl); /* ignores error */
curl_easy_cleanup(curl);
return NULL;
}
int main(int argc, char **argv)
{
pthread_t tid[NUMT];
int i;
(void)argc; /* we do not use any arguments in this example */
(void)argv;
/* Must initialize libcurl before any threads are started */
curl_global_init(CURL_GLOBAL_ALL);
for(i = 0; i< NUMT; i++) {
int error = pthread_create(&tid[i],
NULL, /* default attributes please */
pull_one_url,
(void *)urls[i]);
if(0 != error)
fprintf(stderr, "Couldn't run thread number %d, errno %d\n", i, error);
else
fprintf(stderr, "Thread %d, gets %s\n", i, urls[i]);
}
/* now wait for all threads to terminate */
for(i = 0; i< NUMT; i++) {
pthread_join(tid[i], NULL);
fprintf(stderr, "Thread %d terminated\n", i);
}
return 0;
}