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 * A basic application source code using the multi interface doing two
26 * transfers in parallel without curl_multi_wait/poll.
27 * </DESC>
28 */
29
30 #include <stdio.h>
31 #include <string.h>
32
33 /* somewhat unix-specific */
34 #include <sys/time.h>
35 #include <unistd.h>
36
37 /* curl stuff */
38 #include <curl/curl.h>
39
40 /*
41 * Download an HTTP file and upload an FTP file simultaneously.
42 */
43
44 #define HANDLECOUNT 2 /* Number of simultaneous transfers */
45 #define HTTP_HANDLE 0 /* Index for the HTTP transfer */
46 #define FTP_HANDLE 1 /* Index for the FTP transfer */
47
main(void)48 int main(void)
49 {
50 CURL *handles[HANDLECOUNT];
51 CURLM *multi_handle;
52
53 int still_running = 0; /* keep number of running handles */
54 int i;
55
56 CURLMsg *msg; /* for picking up messages with the transfer status */
57 int msgs_left; /* how many messages are left */
58
59 /* Allocate one CURL handle per transfer */
60 for(i = 0; i<HANDLECOUNT; i++)
61 handles[i] = curl_easy_init();
62
63 /* set the options (I left out a few, you will get the point anyway) */
64 curl_easy_setopt(handles[HTTP_HANDLE], CURLOPT_URL, "https://example.com");
65
66 curl_easy_setopt(handles[FTP_HANDLE], CURLOPT_URL, "ftp://example.com");
67 curl_easy_setopt(handles[FTP_HANDLE], CURLOPT_UPLOAD, 1L);
68
69 /* init a multi stack */
70 multi_handle = curl_multi_init();
71
72 /* add the individual transfers */
73 for(i = 0; i<HANDLECOUNT; i++)
74 curl_multi_add_handle(multi_handle, handles[i]);
75
76 /* we start some action by calling perform right away */
77 curl_multi_perform(multi_handle, &still_running);
78
79 while(still_running) {
80 struct timeval timeout;
81 int rc; /* select() return code */
82 CURLMcode mc; /* curl_multi_fdset() return code */
83
84 fd_set fdread;
85 fd_set fdwrite;
86 fd_set fdexcep;
87 int maxfd = -1;
88
89 long curl_timeo = -1;
90
91 FD_ZERO(&fdread);
92 FD_ZERO(&fdwrite);
93 FD_ZERO(&fdexcep);
94
95 /* set a suitable timeout to play around with */
96 timeout.tv_sec = 1;
97 timeout.tv_usec = 0;
98
99 curl_multi_timeout(multi_handle, &curl_timeo);
100 if(curl_timeo >= 0) {
101 timeout.tv_sec = curl_timeo / 1000;
102 if(timeout.tv_sec > 1)
103 timeout.tv_sec = 1;
104 else
105 timeout.tv_usec = (int)(curl_timeo % 1000) * 1000;
106 }
107
108 /* get file descriptors from the transfers */
109 mc = curl_multi_fdset(multi_handle, &fdread, &fdwrite, &fdexcep, &maxfd);
110
111 if(mc != CURLM_OK) {
112 fprintf(stderr, "curl_multi_fdset() failed, code %d.\n", mc);
113 break;
114 }
115
116 /* On success the value of maxfd is guaranteed to be >= -1. We call
117 select(maxfd + 1, ...); specially in case of (maxfd == -1) there are
118 no fds ready yet so we call select(0, ...) --or Sleep() on Windows--
119 to sleep 100ms, which is the minimum suggested value in the
120 curl_multi_fdset() doc. */
121
122 if(maxfd == -1) {
123 #ifdef _WIN32
124 Sleep(100);
125 rc = 0;
126 #else
127 /* Portable sleep for platforms other than Windows. */
128 struct timeval wait = { 0, 100 * 1000 }; /* 100ms */
129 rc = select(0, NULL, NULL, NULL, &wait);
130 #endif
131 }
132 else {
133 /* Note that on some platforms 'timeout' may be modified by select().
134 If you need access to the original value save a copy beforehand. */
135 rc = select(maxfd + 1, &fdread, &fdwrite, &fdexcep, &timeout);
136 }
137
138 switch(rc) {
139 case -1:
140 /* select error */
141 break;
142 case 0: /* timeout */
143 default: /* action */
144 curl_multi_perform(multi_handle, &still_running);
145 break;
146 }
147 }
148
149 /* See how the transfers went */
150 while((msg = curl_multi_info_read(multi_handle, &msgs_left))) {
151 if(msg->msg == CURLMSG_DONE) {
152 int idx;
153
154 /* Find out which handle this message is about */
155 for(idx = 0; idx<HANDLECOUNT; idx++) {
156 int found = (msg->easy_handle == handles[idx]);
157 if(found)
158 break;
159 }
160
161 switch(idx) {
162 case HTTP_HANDLE:
163 printf("HTTP transfer completed with status %d\n", msg->data.result);
164 break;
165 case FTP_HANDLE:
166 printf("FTP transfer completed with status %d\n", msg->data.result);
167 break;
168 }
169 }
170 }
171
172 curl_multi_cleanup(multi_handle);
173
174 /* Free the CURL handles */
175 for(i = 0; i<HANDLECOUNT; i++)
176 curl_easy_cleanup(handles[i]);
177
178 return 0;
179 }
180