CMakeLua/Utilities/cmcurl-7.19.0/docs/examples/10-at-a-time.c

   1 /*****************************************************************************
   2  *                                  _   _ ____  _
   3  *  Project                     ___| | | |  _ \| |
   4  *                             / __| | | | |_) | |
   5  *                            | (__| |_| |  _ <| |___
   6  *                             \___|\___/|_| \_\_____|
   7  *
   8  * $Id: 10-at-a-time.c,v 1.1.1.1 2008-09-23 16:32:05 hoffman Exp $
   9  *
  10  * Example application source code using the multi interface to download many
  11  * files, but with a capped maximum amount of simultaneous transfers.
  12  *
  13  * Written by Michael Wallner
  14  */
  15
  16 #include <errno.h>
  17 #include <stdlib.h>
  18 #include <string.h>
  19 #ifndef WIN32
  20 #  include <unistd.h>
  21 #endif
  22 #include <curl/multi.h>
  23
  24 static const char *urls[] = {
  25   "http://www.microsoft.com",
  26   "http://www.opensource.org",
  27   "http://www.google.com",
  28   "http://www.yahoo.com",
  29   "http://www.ibm.com",
  30   "http://www.mysql.com",
  31   "http://www.oracle.com",
  32   "http://www.ripe.net",
  33   "http://www.iana.org",
  34   "http://www.amazon.com",
  35   "http://www.netcraft.com",
  36   "http://www.heise.de",
  37   "http://www.chip.de",
  38   "http://www.ca.com",
  39   "http://www.cnet.com",
  40   "http://www.news.com",
  41   "http://www.cnn.com",
  42   "http://www.wikipedia.org",
  43   "http://www.dell.com",
  44   "http://www.hp.com",
  45   "http://www.cert.org",
  46   "http://www.mit.edu",
  47   "http://www.nist.gov",
  48   "http://www.ebay.com",
  49   "http://www.playstation.com",
  50   "http://www.uefa.com",
  51   "http://www.ieee.org",
  52   "http://www.apple.com",
  53   "http://www.sony.com",
  54   "http://www.symantec.com",
  55   "http://www.zdnet.com",
  56   "http://www.fujitsu.com",
  57   "http://www.supermicro.com",
  58   "http://www.hotmail.com",
  59   "http://www.ecma.com",
  60   "http://www.bbc.co.uk",
  61   "http://news.google.com",
  62   "http://www.foxnews.com",
  63   "http://www.msn.com",
  64   "http://www.wired.com",
  65   "http://www.sky.com",
  66   "http://www.usatoday.com",
  67   "http://www.cbs.com",
  68   "http://www.nbc.com",
  69   "http://slashdot.org",
  70   "http://www.bloglines.com",
  71   "http://www.techweb.com",
  72   "http://www.newslink.org",
  73   "http://www.un.org",
  74 };
  75
  76 #define MAX 10 /* number of simultaneous transfers */
  77 #define CNT sizeof(urls)/sizeof(char*) /* total number of transfers to do */
  78
  79 static size_t cb(char *d, size_t n, size_t l, void *p)
  80 {
  81   /* take care of the data here, ignored in this example */
  82   (void)d;
  83   (void)p;
  84   return n*l;
  85 }
  86
  87 static void init(CURLM *cm, int i)
  88 {
  89   CURL *eh = curl_easy_init();
  90
  91   curl_easy_setopt(eh, CURLOPT_WRITEFUNCTION, cb);
  92   curl_easy_setopt(eh, CURLOPT_HEADER, 0L);
  93   curl_easy_setopt(eh, CURLOPT_URL, urls[i]);
  94   curl_easy_setopt(eh, CURLOPT_PRIVATE, urls[i]);
  95   curl_easy_setopt(eh, CURLOPT_VERBOSE, 0L);
  96
  97   curl_multi_add_handle(cm, eh);
  98 }
  99
 100 int main(void)
 101 {
 102   CURLM *cm;
 103   CURLMsg *msg;
 104   long L;
 105   unsigned int C=0;
 106   int M, Q, U = -1;
 107   fd_set R, W, E;
 108   struct timeval T;
 109
 110   curl_global_init(CURL_GLOBAL_ALL);
 111
 112   cm = curl_multi_init();
 113
 114   /* we can optionally limit the total amount of connections this multi handle
 115      uses */
 116   curl_multi_setopt(cm, CURLMOPT_MAXCONNECTS, MAX);
 117
 118   for (C = 0; C < MAX; ++C) {
 119     init(cm, C);
 120   }
 121
 122   while (U) {
 123     while (CURLM_CALL_MULTI_PERFORM == curl_multi_perform(cm, &U));
 124
 125     if (U) {
 126       FD_ZERO(&R);
 127       FD_ZERO(&W);
 128       FD_ZERO(&E);
 129
 130       if (curl_multi_fdset(cm, &R, &W, &E, &M)) {
 131         fprintf(stderr, "E: curl_multi_fdset\n");
 132         return EXIT_FAILURE;
 133       }
 134
 135       if (curl_multi_timeout(cm, &L)) {
 136         fprintf(stderr, "E: curl_multi_timeout\n");
 137         return EXIT_FAILURE;
 138       }
 139       if (L == -1)
 140         L = 100;
 141
 142       if (M == -1) {
 143 #ifdef WIN32
 144         Sleep(L);
 145 #else
 146         sleep(L / 1000);
 147 #endif
 148       } else {
 149         T.tv_sec = L/1000;
 150         T.tv_usec = (L%1000)*1000;
 151
 152         if (0 > select(M+1, &R, &W, &E, &T)) {
 153           fprintf(stderr, "E: select(%i,,,,%li): %i: %s\n",
 154               M+1, L, errno, strerror(errno));
 155           return EXIT_FAILURE;
 156         }
 157       }
 158     }
 159
 160     while ((msg = curl_multi_info_read(cm, &Q))) {
 161       if (msg->msg == CURLMSG_DONE) {
 162         char *url;
 163         CURL *e = msg->easy_handle;
 164         curl_easy_getinfo(msg->easy_handle, CURLINFO_PRIVATE, &url);
 165         fprintf(stderr, "R: %d - %s <%s>\n",
 166                 msg->data.result, curl_easy_strerror(msg->data.result), url);
 167         curl_multi_remove_handle(cm, e);
 168         curl_easy_cleanup(e);
 169       }
 170       else {
 171         fprintf(stderr, "E: CURLMsg (%d)\n", msg->msg);
 172       }
 173       if (C < CNT) {
 174         init(cm, C++);
 175         U++; /* just to prevent it from remaining at 0 if there are more
 176                 URLs to get */
 177       }
 178     }
 179   }
 180
 181   curl_multi_cleanup(cm);
 182   curl_global_cleanup();
 183
 184   return EXIT_SUCCESS;
 185 }