1/***************************************************************************
2 *                                  _   _ ____  _
3 *  Project                     ___| | | |  _ \| |
4 *                             / __| | | | |_) | |
5 *                            | (__| |_| |  _ <| |___
6 *                             \___|\___/|_| \_\_____|
7 *
8 * Copyright (C) 1998 - 2016, 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.haxx.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 ***************************************************************************/
22/* <DESC>
23 * A basic application source code using the multi interface doing two
24 * transfers in parallel.
25 * </DESC>
26 */
27
28#include <stdio.h>
29#include <string.h>
30
31/* somewhat unix-specific */
32#include <sys/time.h>
33#include <unistd.h>
34
35/* curl stuff */
36#include <curl/curl.h>
37
38/*
39 * Download a HTTP file and upload an FTP file simultaneously.
40 */
41
42#define HANDLECOUNT 2   /* Number of simultaneous transfers */
43#define HTTP_HANDLE 0   /* Index for the HTTP transfer */
44#define FTP_HANDLE 1    /* Index for the FTP transfer */
45
46int main(void)
47{
48  CURL *handles[HANDLECOUNT];
49  CURLM *multi_handle;
50
51  int still_running; /* keep number of running handles */
52  int i;
53
54  CURLMsg *msg; /* for picking up messages with the transfer status */
55  int msgs_left; /* how many messages are left */
56
57  /* Allocate one CURL handle per transfer */
58  for(i=0; i<HANDLECOUNT; i++)
59    handles[i] = curl_easy_init();
60
61  /* set the options (I left out a few, you'll get the point anyway) */
62  curl_easy_setopt(handles[HTTP_HANDLE], CURLOPT_URL, "http://example.com");
63
64  curl_easy_setopt(handles[FTP_HANDLE], CURLOPT_URL, "ftp://example.com");
65  curl_easy_setopt(handles[FTP_HANDLE], CURLOPT_UPLOAD, 1L);
66
67  /* init a multi stack */
68  multi_handle = curl_multi_init();
69
70  /* add the individual transfers */
71  for(i=0; i<HANDLECOUNT; i++)
72    curl_multi_add_handle(multi_handle, handles[i]);
73
74  /* we start some action by calling perform right away */
75  curl_multi_perform(multi_handle, &still_running);
76
77  do {
78    struct timeval timeout;
79    int rc; /* select() return code */
80    CURLMcode mc; /* curl_multi_fdset() return code */
81
82    fd_set fdread;
83    fd_set fdwrite;
84    fd_set fdexcep;
85    int maxfd = -1;
86
87    long curl_timeo = -1;
88
89    FD_ZERO(&fdread);
90    FD_ZERO(&fdwrite);
91    FD_ZERO(&fdexcep);
92
93    /* set a suitable timeout to play around with */
94    timeout.tv_sec = 1;
95    timeout.tv_usec = 0;
96
97    curl_multi_timeout(multi_handle, &curl_timeo);
98    if(curl_timeo >= 0) {
99      timeout.tv_sec = curl_timeo / 1000;
100      if(timeout.tv_sec > 1)
101        timeout.tv_sec = 1;
102      else
103        timeout.tv_usec = (curl_timeo % 1000) * 1000;
104    }
105
106    /* get file descriptors from the transfers */
107    mc = curl_multi_fdset(multi_handle, &fdread, &fdwrite, &fdexcep, &maxfd);
108
109    if(mc != CURLM_OK) {
110      fprintf(stderr, "curl_multi_fdset() failed, code %d.\n", mc);
111      break;
112    }
113
114    /* On success the value of maxfd is guaranteed to be >= -1. We call
115       select(maxfd + 1, ...); specially in case of (maxfd == -1) there are
116       no fds ready yet so we call select(0, ...) --or Sleep() on Windows--
117       to sleep 100ms, which is the minimum suggested value in the
118       curl_multi_fdset() doc. */
119
120    if(maxfd == -1) {
121#ifdef _WIN32
122      Sleep(100);
123      rc = 0;
124#else
125      /* Portable sleep for platforms other than Windows. */
126      struct timeval wait = { 0, 100 * 1000 }; /* 100ms */
127      rc = select(0, NULL, NULL, NULL, &wait);
128#endif
129    }
130    else {
131      /* Note that on some platforms 'timeout' may be modified by select().
132         If you need access to the original value save a copy beforehand. */
133      rc = select(maxfd+1, &fdread, &fdwrite, &fdexcep, &timeout);
134    }
135
136    switch(rc) {
137    case -1:
138      /* select error */
139      break;
140    case 0: /* timeout */
141    default: /* action */
142      curl_multi_perform(multi_handle, &still_running);
143      break;
144    }
145  } while(still_running);
146
147  /* See how the transfers went */
148  while((msg = curl_multi_info_read(multi_handle, &msgs_left))) {
149    if(msg->msg == CURLMSG_DONE) {
150      int idx, found = 0;
151
152      /* Find out which handle this message is about */
153      for(idx=0; idx<HANDLECOUNT; idx++) {
154        found = (msg->easy_handle == handles[idx]);
155        if(found)
156          break;
157      }
158
159      switch (idx) {
160      case HTTP_HANDLE:
161        printf("HTTP transfer completed with status %d\n", msg->data.result);
162        break;
163      case FTP_HANDLE:
164        printf("FTP transfer completed with status %d\n", msg->data.result);
165        break;
166      }
167    }
168  }
169
170  curl_multi_cleanup(multi_handle);
171
172  /* Free the CURL handles */
173  for(i=0; i<HANDLECOUNT; i++)
174    curl_easy_cleanup(handles[i]);
175
176  return 0;
177}
178