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 #ifndef _WIN32
35 #include <sys/time.h>
36 #include <unistd.h>
37 #endif
38
39 /* curl stuff */
40 #include <curl/curl.h>
41
42 /*
43 * Download an HTTP file and upload an FTP file simultaneously.
44 */
45
46 #define HANDLECOUNT 2 /* Number of simultaneous transfers */
47 #define HTTP_HANDLE 0 /* Index for the HTTP transfer */
48 #define FTP_HANDLE 1 /* Index for the FTP transfer */
49
main(void)50 int main(void)
51 {
52 CURL *handles[HANDLECOUNT];
53 CURLM *multi_handle;
54
55 int still_running = 0; /* keep number of running handles */
56 int i;
57
58 CURLMsg *msg; /* for picking up messages with the transfer status */
59 int msgs_left; /* how many messages are left */
60
61 /* Allocate one CURL handle per transfer */
62 for(i = 0; i < HANDLECOUNT; i++)
63 handles[i] = curl_easy_init();
64
65 /* set the options (I left out a few, you get the point anyway) */
66 curl_easy_setopt(handles[HTTP_HANDLE], CURLOPT_URL, "https://example.com");
67
68 curl_easy_setopt(handles[FTP_HANDLE], CURLOPT_URL, "ftp://example.com");
69 curl_easy_setopt(handles[FTP_HANDLE], CURLOPT_UPLOAD, 1L);
70
71 /* init a multi stack */
72 multi_handle = curl_multi_init();
73
74 /* add the individual transfers */
75 for(i = 0; i < HANDLECOUNT; i++)
76 curl_multi_add_handle(multi_handle, handles[i]);
77
78 /* we start some action by calling perform right away */
79 curl_multi_perform(multi_handle, &still_running);
80
81 while(still_running) {
82 struct timeval timeout;
83 int rc; /* select() return code */
84 CURLMcode mc; /* curl_multi_fdset() return code */
85
86 fd_set fdread;
87 fd_set fdwrite;
88 fd_set fdexcep;
89 int maxfd = -1;
90
91 long curl_timeo = -1;
92
93 FD_ZERO(&fdread);
94 FD_ZERO(&fdwrite);
95 FD_ZERO(&fdexcep);
96
97 /* set a suitable timeout to play around with */
98 timeout.tv_sec = 1;
99 timeout.tv_usec = 0;
100
101 curl_multi_timeout(multi_handle, &curl_timeo);
102 if(curl_timeo >= 0) {
103 timeout.tv_sec = curl_timeo / 1000;
104 if(timeout.tv_sec > 1)
105 timeout.tv_sec = 1;
106 else
107 timeout.tv_usec = (int)(curl_timeo % 1000) * 1000;
108 }
109
110 /* get file descriptors from the transfers */
111 mc = curl_multi_fdset(multi_handle, &fdread, &fdwrite, &fdexcep, &maxfd);
112
113 if(mc != CURLM_OK) {
114 fprintf(stderr, "curl_multi_fdset() failed, code %d.\n", mc);
115 break;
116 }
117
118 /* On success the value of maxfd is guaranteed to be >= -1. We call
119 select(maxfd + 1, ...); specially in case of (maxfd == -1) there are
120 no fds ready yet so we call select(0, ...) --or Sleep() on Windows--
121 to sleep 100ms, which is the minimum suggested value in the
122 curl_multi_fdset() doc. */
123
124 if(maxfd == -1) {
125 #ifdef _WIN32
126 Sleep(100);
127 rc = 0;
128 #else
129 /* Portable sleep for platforms other than Windows. */
130 struct timeval wait = { 0, 100 * 1000 }; /* 100ms */
131 rc = select(0, NULL, NULL, NULL, &wait);
132 #endif
133 }
134 else {
135 /* Note that on some platforms 'timeout' may be modified by select().
136 If you need access to the original value save a copy beforehand. */
137 rc = select(maxfd + 1, &fdread, &fdwrite, &fdexcep, &timeout);
138 }
139
140 switch(rc) {
141 case -1:
142 /* select error */
143 break;
144 case 0: /* timeout */
145 default: /* action */
146 curl_multi_perform(multi_handle, &still_running);
147 break;
148 }
149 }
150
151 /* See how the transfers went */
152 /* !checksrc! disable EQUALSNULL 1 */
153 while((msg = curl_multi_info_read(multi_handle, &msgs_left)) != NULL) {
154 if(msg->msg == CURLMSG_DONE) {
155 int idx;
156
157 /* Find out which handle this message is about */
158 for(idx = 0; idx < HANDLECOUNT; idx++) {
159 int found = (msg->easy_handle == handles[idx]);
160 if(found)
161 break;
162 }
163
164 switch(idx) {
165 case HTTP_HANDLE:
166 printf("HTTP transfer completed with status %d\n", msg->data.result);
167 break;
168 case FTP_HANDLE:
169 printf("FTP transfer completed with status %d\n", msg->data.result);
170 break;
171 }
172 }
173 }
174
175 curl_multi_cleanup(multi_handle);
176
177 /* Free the CURL handles */
178 for(i = 0; i < HANDLECOUNT; i++)
179 curl_easy_cleanup(handles[i]);
180
181 return 0;
182 }
183
