Return to threaded-shared-conn.c CVS log

Up to [ELWIX - Embedded LightWeight unIX -] / embedaddon / curl / docs / examples

Annotation of embedaddon/curl/docs/examples/threaded-shared-conn.c, revision 1.1

1.1     ! misho       1: /***************************************************************************
        !             2:  *                                  _   _ ____  _
        !             3:  *  Project                     ___| | | |  _ \| |
        !             4:  *                             / __| | | | |_) | |
        !             5:  *                            | (__| |_| |  _ <| |___
        !             6:  *                             \___|\___/|_| \_\_____|
        !             7:  *
        !             8:  * Copyright (C) 1998 - 2019, Daniel Stenberg, <daniel@haxx.se>, et al.
        !             9:  *
        !            10:  * This software is licensed as described in the file COPYING, which
        !            11:  * you should have received as part of this distribution. The terms
        !            12:  * are also available at https://curl.haxx.se/docs/copyright.html.
        !            13:  *
        !            14:  * You may opt to use, copy, modify, merge, publish, distribute and/or sell
        !            15:  * copies of the Software, and permit persons to whom the Software is
        !            16:  * furnished to do so, under the terms of the COPYING file.
        !            17:  *
        !            18:  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
        !            19:  * KIND, either express or implied.
        !            20:  *
        !            21:  ***************************************************************************/
        !            22: /* <DESC>
        !            23:  * Multi-threaded transfers sharing a single connection pool
        !            24:  * </DESC>
        !            25:  *
        !            26:  * This example fires up NUM_THREADS threads and in each single thread, it
        !            27:  * downloads the same fixed URL a URL_ITERATIONS number of times. The received
        !            28:  * data is just thrown away. It sets up a single shared object that holds the
        !            29:  * connection cache and all easy handles in all threads share that same cache.
        !            30:  *
        !            31:  * This example uses pthreads for threads and mutexes, but should be easy to
        !            32:  * modify to use different thread/mutex system should you want to.
        !            33:  *
        !            34:  */
        !            35: 
        !            36: #include <stdio.h>
        !            37: #include <pthread.h>
        !            38: #include <curl/curl.h>
        !            39: 
        !            40: /*
        !            41:   URL to fetch. If you select HTTPS, you need to use a TLS backend with mutex
        !            42:   locks taken care of (OpenSSL 1.1.x, NSS, etc) or add SSL mutex callbacks!
        !            43: */
        !            44: #define URL "http://localhost/4KB"
        !            45: 
        !            46: /* number of threads to fire up in parallel */
        !            47: #define NUM_THREADS 67
        !            48: 
        !            49: /* how many times each URL is transferred per thread */
        !            50: #define URL_ITERATIONS 11235
        !            51: 
        !            52: static pthread_mutex_t connlock;
        !            53: 
        !            54: static size_t write_db(void *ptr, size_t size, size_t nmemb, void *data)
        !            55: {
        !            56:   /* not interested in the downloaded bytes, return the size */
        !            57:   (void)ptr;  /* unused */
        !            58:   (void)data; /* unused */
        !            59:   return (size_t)(size * nmemb);
        !            60: }
        !            61: 
        !            62: static void lock_cb(CURL *handle, curl_lock_data data,
        !            63:                     curl_lock_access access, void *userptr)
        !            64: {
        !            65:   (void)access; /* unused */
        !            66:   (void)userptr; /* unused */
        !            67:   (void)handle; /* unused */
        !            68:   (void)data; /* unused */
        !            69:   pthread_mutex_lock(&connlock);
        !            70: }
        !            71: 
        !            72: static void unlock_cb(CURL *handle, curl_lock_data data,
        !            73:                       void *userptr)
        !            74: {
        !            75:   (void)userptr; /* unused */
        !            76:   (void)handle;  /* unused */
        !            77:   (void)data;    /* unused */
        !            78:   pthread_mutex_unlock(&connlock);
        !            79: }
        !            80: 
        !            81: static void init_locks(void)
        !            82: {
        !            83:   pthread_mutex_init(&connlock, NULL);
        !            84: }
        !            85: 
        !            86: static void kill_locks(void)
        !            87: {
        !            88:   pthread_mutex_destroy(&connlock);
        !            89: }
        !            90: 
        !            91: struct initurl {
        !            92:   const char *url;
        !            93:   CURLSH *share;
        !            94:   int threadno;
        !            95: };
        !            96: 
        !            97: static void *run_thread(void *ptr)
        !            98: {
        !            99:   struct initurl *u = (struct initurl *)ptr;
        !           100:   int i;
        !           101: 
        !           102:   for(i = 0; i < URL_ITERATIONS; i++) {
        !           103:     CURL *curl = curl_easy_init();
        !           104:     curl_easy_setopt(curl, CURLOPT_URL, u->url);
        !           105:     curl_easy_setopt(curl, CURLOPT_VERBOSE, 0L);
        !           106:     curl_easy_setopt(curl, CURLOPT_SHARE, u->share);
        !           107:     curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_db);
        !           108:     curl_easy_perform(curl); /* ignores error */
        !           109:     curl_easy_cleanup(curl);
        !           110:     fprintf(stderr, "Thread %d transfer %d\n", u->threadno, i);
        !           111:   }
        !           112: 
        !           113:   return NULL;
        !           114: }
        !           115: 
        !           116: int main(void)
        !           117: {
        !           118:   pthread_t tid[NUM_THREADS];
        !           119:   int i;
        !           120:   CURLSH *share;
        !           121:   struct initurl url[NUM_THREADS];
        !           122: 
        !           123:   /* Must initialize libcurl before any threads are started */
        !           124:   curl_global_init(CURL_GLOBAL_ALL);
        !           125: 
        !           126:   share = curl_share_init();
        !           127:   curl_share_setopt(share, CURLSHOPT_LOCKFUNC, lock_cb);
        !           128:   curl_share_setopt(share, CURLSHOPT_UNLOCKFUNC, unlock_cb);
        !           129:   curl_share_setopt(share, CURLSHOPT_SHARE, CURL_LOCK_DATA_CONNECT);
        !           130: 
        !           131:   init_locks();
        !           132: 
        !           133:   for(i = 0; i< NUM_THREADS; i++) {
        !           134:     int error;
        !           135:     url[i].url = URL;
        !           136:     url[i].share = share;
        !           137:     url[i].threadno = i;
        !           138:     error = pthread_create(&tid[i], NULL, run_thread, &url[i]);
        !           139:     if(0 != error)
        !           140:       fprintf(stderr, "Couldn't run thread number %d, errno %d\n", i, error);
        !           141:     else
        !           142:       fprintf(stderr, "Thread %d, gets %s\n", i, URL);
        !           143:   }
        !           144: 
        !           145:   /* now wait for all threads to terminate */
        !           146:   for(i = 0; i< NUM_THREADS; i++) {
        !           147:     pthread_join(tid[i], NULL);
        !           148:     fprintf(stderr, "Thread %d terminated\n", i);
        !           149:   }
        !           150: 
        !           151:   kill_locks();
        !           152: 
        !           153:   curl_share_cleanup(share);
        !           154:   curl_global_cleanup();
        !           155:   return 0;
        !           156: }