1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
|
/*****************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* $Id$
*
* A multi-threaded example that uses pthreads and fetches 4 remote files at
* once over HTTPS. The lock callbacks and stuff assume OpenSSL so far.
* Should be expanded to do optional GnuTLS style locking.
*
* OpenSSL docs for this: http://www.openssl.org/docs/crypto/threads.html
*/
#include <stdio.h>
#include <pthread.h>
#include <curl/curl.h>
#include <openssl/crypto.h>
/* we have this global to let the callback get easy access to it */
static pthread_mutex_t *lockarray;
static void lock_callback(int mode, int type, char *file, int line)
{
(void)file;
(void)line;
if (mode & CRYPTO_LOCK) {
pthread_mutex_lock(&(lockarray[type]));
}
else {
pthread_mutex_unlock(&(lockarray[type]));
}
}
static unsigned long thread_id(void)
{
unsigned long ret;
ret=(unsigned long)pthread_self();
return(ret);
}
static void init_locks(void)
{
int i;
lockarray=(pthread_mutex_t *)OPENSSL_malloc(CRYPTO_num_locks() *
sizeof(pthread_mutex_t));
for (i=0; i<CRYPTO_num_locks(); i++) {
pthread_mutex_init(&(lockarray[i]),NULL);
}
CRYPTO_set_id_callback((unsigned long (*)())thread_id);
CRYPTO_set_locking_callback((void (*)())lock_callback);
}
static void kill_locks(void)
{
int i;
CRYPTO_set_locking_callback(NULL);
for (i=0; i<CRYPTO_num_locks(); i++)
pthread_mutex_destroy(&(lockarray[i]));
OPENSSL_free(lockarray);
}
/* List of URLs to fetch.*/
const char *urls[]= {
"https://www.sf.net/",
"https://www.openssl.org/",
"https://www.sf.net/",
"https://www.openssl.org/",
};
static void *pull_one_url(void *url)
{
CURL *curl;
curl = curl_easy_init();
curl_easy_setopt(curl, CURLOPT_URL, url);
/* this example doesn't verify the server's certificate, which means we
might be downloading stuff from an impostor */
curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 0);
curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 0);
curl_easy_perform(curl); /* ignores error */
curl_easy_cleanup(curl);
return NULL;
}
int main(int argc, char **argv)
{
pthread_t tid[4];
int i;
int error;
(void)argc; /* we don't use any arguments in this example */
(void)argv;
init_locks();
for(i=0; i< 4; i++) {
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< 4; i++) {
error = pthread_join(tid[i], NULL);
fprintf(stderr, "Thread %d terminated\n", i);
}
kill_locks();
return 0;
}
|
