1 /***************************************************************************
2 * _ _ ____ _
3 * Project ___| | | | _ \| |
4 * / __| | | | |_) | |
5 * | (__| |_| | _ <| |___
6 * \___|\___/|_| \_\_____|
7 *
8 * Copyright (C) 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.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 * SPDX-License-Identifier: curl
22 *
23 ***************************************************************************/
24 /* <DESC>
25 * Download many files in parallel, in the same thread.
26 * </DESC>
27 */
28
29 #include <stdlib.h>
30 #include <string.h>
31 #include <curl/curl.h>
32
33 static const char *urls[] = {
34 "https://www.microsoft.com",
35 "https://opensource.org",
36 "https://www.google.com",
37 "https://www.yahoo.com",
38 "https://www.ibm.com",
39 "https://www.mysql.com",
40 "https://www.oracle.com",
41 "https://www.ripe.net",
42 "https://www.iana.org",
43 "https://www.amazon.com",
44 "https://www.netcraft.com",
45 "https://www.heise.de",
46 "https://www.chip.de",
47 "https://www.ca.com",
48 "https://www.cnet.com",
49 "https://www.mozilla.org",
50 "https://www.cnn.com",
51 "https://www.wikipedia.org",
52 "https://www.dell.com",
53 "https://www.hp.com",
54 "https://www.cert.org",
55 "https://www.mit.edu",
56 "https://www.nist.gov",
57 "https://www.ebay.com",
58 "https://www.playstation.com",
59 "https://www.uefa.com",
60 "https://www.ieee.org",
61 "https://www.apple.com",
62 "https://www.symantec.com",
63 "https://www.zdnet.com",
64 "https://www.fujitsu.com/global/",
65 "https://www.supermicro.com",
66 "https://www.hotmail.com",
67 "https://www.ietf.org",
68 "https://www.bbc.co.uk",
69 "https://news.google.com",
70 "https://www.foxnews.com",
71 "https://www.msn.com",
72 "https://www.wired.com",
73 "https://www.sky.com",
74 "https://www.usatoday.com",
75 "https://www.cbs.com",
76 "https://www.nbc.com/",
77 "https://slashdot.org",
78 "https://www.informationweek.com",
79 "https://apache.org",
80 "https://www.un.org",
81 };
82
83 #define MAX_PARALLEL 10 /* number of simultaneous transfers */
84 #define NUM_URLS sizeof(urls)/sizeof(char *)
85
write_cb(char * data,size_t n,size_t l,void * userp)86 static size_t write_cb(char *data, size_t n, size_t l, void *userp)
87 {
88 /* take care of the data here, ignored in this example */
89 (void)data;
90 (void)userp;
91 return n*l;
92 }
93
add_transfer(CURLM * cm,unsigned int i,int * left)94 static void add_transfer(CURLM *cm, unsigned int i, int *left)
95 {
96 CURL *eh = curl_easy_init();
97 curl_easy_setopt(eh, CURLOPT_WRITEFUNCTION, write_cb);
98 curl_easy_setopt(eh, CURLOPT_URL, urls[i]);
99 curl_easy_setopt(eh, CURLOPT_PRIVATE, urls[i]);
100 curl_multi_add_handle(cm, eh);
101 (*left)++;
102 }
103
main(void)104 int main(void)
105 {
106 CURLM *cm;
107 CURLMsg *msg;
108 unsigned int transfers = 0;
109 int msgs_left = -1;
110 int left = 0;
111
112 curl_global_init(CURL_GLOBAL_ALL);
113 cm = curl_multi_init();
114
115 /* Limit the amount of simultaneous connections curl should allow: */
116 curl_multi_setopt(cm, CURLMOPT_MAXCONNECTS, (long)MAX_PARALLEL);
117
118 for(transfers = 0; transfers < MAX_PARALLEL && transfers < NUM_URLS;
119 transfers++)
120 add_transfer(cm, transfers, &left);
121
122 do {
123 int still_alive = 1;
124 curl_multi_perform(cm, &still_alive);
125
126 /* !checksrc! disable EQUALSNULL 1 */
127 while((msg = curl_multi_info_read(cm, &msgs_left)) != NULL) {
128 if(msg->msg == CURLMSG_DONE) {
129 char *url;
130 CURL *e = msg->easy_handle;
131 curl_easy_getinfo(msg->easy_handle, CURLINFO_PRIVATE, &url);
132 fprintf(stderr, "R: %d - %s <%s>\n",
133 msg->data.result, curl_easy_strerror(msg->data.result), url);
134 curl_multi_remove_handle(cm, e);
135 curl_easy_cleanup(e);
136 left--;
137 }
138 else {
139 fprintf(stderr, "E: CURLMsg (%d)\n", msg->msg);
140 }
141 if(transfers < NUM_URLS)
142 add_transfer(cm, transfers++, &left);
143 }
144 if(left)
145 curl_multi_wait(cm, NULL, 0, 1000, NULL);
146
147 } while(left);
148
149 curl_multi_cleanup(cm);
150 curl_global_cleanup();
151
152 return EXIT_SUCCESS;
153 }
154
