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| -rw-r--r-- | docs/examples/Makefile.inc | 2 | ||||
| -rw-r--r-- | docs/examples/threaded-shared-conn.c | 156 |
2 files changed, 157 insertions, 1 deletions
diff --git a/docs/examples/Makefile.inc b/docs/examples/Makefile.inc index 075df9ea2..b560882f4 100644 --- a/docs/examples/Makefile.inc +++ b/docs/examples/Makefile.inc @@ -34,7 +34,7 @@ check_PROGRAMS = 10-at-a-time anyauthput cookie_interface debug fileupload \ imap-tls imap-multi url2file sftpget ftpsget postinmemory http2-download \ http2-upload http2-serverpush getredirect ftpuploadfrommem \ ftpuploadresume sslbackend postit2-formadd multi-formadd \ - shared-connection-cache + shared-connection-cache threaded-shared-conn # These examples require external dependencies that may not be commonly # available on POSIX systems, so don't bother attempting to compile them here. diff --git a/docs/examples/threaded-shared-conn.c b/docs/examples/threaded-shared-conn.c new file mode 100644 index 000000000..7ff832e84 --- /dev/null +++ b/docs/examples/threaded-shared-conn.c @@ -0,0 +1,156 @@ +/*************************************************************************** + * _ _ ____ _ + * Project ___| | | | _ \| | + * / __| | | | |_) | | + * | (__| |_| | _ <| |___ + * \___|\___/|_| \_\_____| + * + * Copyright (C) 1998 - 2017, 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.haxx.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. + * + ***************************************************************************/ +/* <DESC> + * Multi-threaded transfers sharing a single connection pool + * </DESC> + * + * This example fires up NUM_THREADS threads and in each single thread, it + * downloads the same fixed URL a URL_ITERATIONS number of times. The received + * data is just thrown away. It sets up a single shared object that holds the + * connection cache and all easy threads in all threads share that same cache. + * + * This example uses pthreads for threads and mutexes, but should be easy to + * modify to use different thread/mutex system should you want to. + * + */ + +#include <stdio.h> +#include <pthread.h> +#include <curl/curl.h> + +/* + URL to fetch. If you select HTTPS, you need to use a TLS backend with mutex + locks taken care of (OpenSSL 1.1.x, NSS, etc) or add SSL mutex callbacks! +*/ +#define URL "http://localhost/4KB" + +/* number of threads to fire up in parallel */ +#define NUM_THREADS 67 + +/* how many times each URL is transferred per thread */ +#define URL_ITERATIONS 11235 + +static pthread_mutex_t connlock; + +static size_t write_db(void *ptr, size_t size, size_t nmemb, void *data) +{ + /* not interested in the downloaded bytes, return the size */ + (void)ptr; /* unused */ + (void)data; /* unused */ + return (size_t)(size * nmemb); +} + +static void lock_cb(CURL *handle, curl_lock_data data, + curl_lock_access access, void *userptr) +{ + (void)access; /* unused */ + (void)userptr; /* unused */ + (void)handle; /* unused */ + (void)data; /* unused */ + pthread_mutex_lock(&connlock); +} + +static void unlock_cb(CURL *handle, curl_lock_data data, + void *userptr) +{ + (void)userptr; /* unused */ + (void)handle; /* unused */ + (void)data; /* unused */ + pthread_mutex_unlock(&connlock); +} + +static void init_locks(void) +{ + pthread_mutex_init(&connlock, NULL); +} + +static void kill_locks(void) +{ + pthread_mutex_destroy(&connlock); +} + +struct initurl { + const char *url; + CURLSH *share; + int threadno; +}; + +static void *run_thread(void *ptr) +{ + struct initurl *u = (struct initurl *)ptr; + int i; + + for(i = 0; i < URL_ITERATIONS; i++) { + CURL *curl = curl_easy_init(); + curl_easy_setopt(curl, CURLOPT_URL, u->url); + curl_easy_setopt(curl, CURLOPT_VERBOSE, 0L); + curl_easy_setopt(curl, CURLOPT_SHARE, u->share); + curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_db); + curl_easy_perform(curl); /* ignores error */ + curl_easy_cleanup(curl); + fprintf(stderr, "Tread %d transfer %d\n", u->threadno, i); + } + + return NULL; +} + +int main(void) +{ + pthread_t tid[NUM_THREADS]; + int i; + int error; + CURLSH *share; + struct initurl url[NUM_THREADS]; + + /* Must initialize libcurl before any threads are started */ + curl_global_init(CURL_GLOBAL_ALL); + + share = curl_share_init(); + curl_share_setopt(share, CURLSHOPT_LOCKFUNC, lock_cb); + curl_share_setopt(share, CURLSHOPT_UNLOCKFUNC, unlock_cb); + curl_share_setopt(share, CURLSHOPT_SHARE, CURL_LOCK_DATA_CONNECT); + + init_locks(); + + for(i = 0; i< NUM_THREADS; i++) { + url[i].url = URL; + url[i].share = share; + url[i].threadno = i; + error = pthread_create(&tid[i], NULL, run_thread, &url[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, URL); + } + + /* now wait for all threads to terminate */ + for(i = 0; i< NUM_THREADS; i++) { + error = pthread_join(tid[i], NULL); + fprintf(stderr, "Thread %d terminated\n", i); + } + + kill_locks(); + + curl_share_cleanup(share); + curl_global_cleanup(); + return 0; +} |