curl-curl/tests/libtest/lib3207.c
Stefan Eissing 82009c4220
share: concurrency handling, easy updates
Replace the `volatile int dirty` with a reference counter
protected by a mutex when available.

Solve the problem of when to call application's lock function
by adding a volatile flag that indicates a share has been added
to easy handles in its lifetime. That flag ever goes from
FALSE to TRUE, so volatile might work (in the absence of a mutex).

(The problem is that the lock/unlock functions need 2-3
`curl_share_setopt()` invocations to become usable and there
is no way of telling if the third will ever happen. Calling
the lock function before the 3rd setopt may crash the
application.)

When removing a share from an easy handle (or replacing it with
another share), detach the easy connection on a share with a
connection pool.

When cleaning up a share, allow this even if it is still used in
easy handles. It will be destroyed when the reference count
drops to 0.

Closes #20870
2026-03-21 14:42:49 +01:00

215 lines
5.7 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
*
***************************************************************************/
#include "first.h"
#include "curl_threads.h"
#define THREAD_SIZE 16
#define PER_THREAD_SIZE 8
struct Ctx {
const char *URL;
CURLSH *share;
CURLcode result;
size_t thread_id;
struct curl_slist *contents;
};
static size_t write_memory_callback(char *contents, size_t size,
size_t nmemb, void *userp)
{
/* append the data to contents */
size_t realsize = size * nmemb;
struct Ctx *mem = (struct Ctx *)userp;
char *data = curlx_malloc(realsize + 1);
struct curl_slist *item_append = NULL;
if(!data) {
curl_mprintf("not enough memory (malloc returned NULL)\n");
return 0;
}
memcpy(data, contents, realsize);
data[realsize] = '\0';
item_append = curl_slist_append(mem->contents, data);
curlx_free(data);
if(item_append) {
mem->contents = item_append;
}
else {
curl_mprintf("not enough memory (curl_slist_append returned NULL)\n");
return 0;
}
return realsize;
}
#ifdef USE_THREADS
static CURL_THREAD_RETURN_T CURL_STDCALL test_thread(void *ptr)
#else
static unsigned int test_thread(void *ptr)
#endif
{
struct Ctx *ctx = (struct Ctx *)ptr;
CURLcode result = CURLE_OK;
int i;
/* Loop the transfer and cleanup the handle properly every lap. This will
still reuse ssl session since the pool is in the shared object! */
for(i = 0; i < PER_THREAD_SIZE; i++) {
CURL *curl = curl_easy_init();
if(curl) {
curl_easy_setopt(curl, CURLOPT_URL, ctx->URL);
/* use the share object */
curl_easy_setopt(curl, CURLOPT_SHARE, ctx->share);
curl_easy_setopt(curl, CURLOPT_CAINFO, libtest_arg2);
curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_memory_callback);
curl_easy_setopt(curl, CURLOPT_WRITEDATA, ptr);
curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L);
/* Perform the request, result will get the return code */
result = curl_easy_perform(curl);
/* always cleanup */
curl_easy_cleanup(curl);
/* Check for errors */
if(result != CURLE_OK) {
curl_mfprintf(stderr, "curl_easy_perform() failed: %s\n",
curl_easy_strerror(result));
goto test_cleanup;
}
}
}
test_cleanup:
ctx->result = result;
return 0;
}
#ifdef USE_THREADS
static void t3207_test_lock(CURL *curl, curl_lock_data data,
curl_lock_access laccess, void *useptr)
{
curl_mutex_t *mutexes = (curl_mutex_t *)useptr;
(void)curl;
(void)laccess;
Curl_mutex_acquire(&mutexes[data]);
}
static void t3207_test_unlock(CURL *curl, curl_lock_data data, void *useptr)
{
curl_mutex_t *mutexes = (curl_mutex_t *)useptr;
(void)curl;
Curl_mutex_release(&mutexes[data]);
}
static void execute(CURLSH *share, struct Ctx *ctx)
{
size_t i;
curl_mutex_t mutexes[CURL_LOCK_DATA_LAST - 1];
curl_thread_t thread[THREAD_SIZE];
for(i = 0; i < CURL_ARRAYSIZE(mutexes); i++) {
Curl_mutex_init(&mutexes[i]);
}
curl_share_setopt(share, CURLSHOPT_LOCKFUNC, t3207_test_lock);
curl_share_setopt(share, CURLSHOPT_UNLOCKFUNC, t3207_test_unlock);
curl_share_setopt(share, CURLSHOPT_USERDATA, (void *)mutexes);
curl_share_setopt(share, CURLSHOPT_SHARE, CURL_LOCK_DATA_SSL_SESSION);
for(i = 0; i < CURL_ARRAYSIZE(thread); i++) {
thread[i] = Curl_thread_create(test_thread, (void *)&ctx[i]);
}
for(i = 0; i < CURL_ARRAYSIZE(thread); i++) {
if(thread[i]) {
Curl_thread_join(&thread[i]);
Curl_thread_destroy(&thread[i]);
}
}
curl_share_setopt(share, CURLSHOPT_LOCKFUNC, NULL);
curl_share_setopt(share, CURLSHOPT_UNLOCKFUNC, NULL);
for(i = 0; i < CURL_ARRAYSIZE(mutexes); i++) {
Curl_mutex_destroy(&mutexes[i]);
}
}
#else /* without pthread, run serially */
static void execute(CURLSH *share, struct Ctx *ctx)
{
size_t i;
(void)share;
for(i = 0; i < THREAD_SIZE; i++) {
test_thread((void *)&ctx[i]);
}
}
#endif
static CURLcode test_lib3207(const char *URL)
{
CURLcode result = CURLE_OK;
size_t i;
CURLSH *share;
struct Ctx ctx[THREAD_SIZE];
curl_global_init(CURL_GLOBAL_ALL);
share = curl_share_init();
if(!share) {
curl_mfprintf(stderr, "curl_share_init() failed\n");
goto test_cleanup;
}
for(i = 0; i < CURL_ARRAYSIZE(ctx); i++) {
ctx[i].share = share;
ctx[i].URL = URL;
ctx[i].thread_id = i;
ctx[i].result = CURLE_OK;
ctx[i].contents = NULL;
}
execute(share, ctx);
for(i = 0; i < CURL_ARRAYSIZE(ctx); i++) {
if(ctx[i].result) {
result = ctx[i].result;
}
else {
struct curl_slist *item = ctx[i].contents;
while(item) {
curl_mprintf("%s", item->data);
item = item->next;
}
}
curl_slist_free_all(ctx[i].contents);
}
test_cleanup:
if(share)
curl_share_cleanup(share);
curl_global_cleanup();
return result;
}