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      1 /***************************************************************************
      2  *                                  _   _ ____  _
      3  *  Project                     ___| | | |  _ \| |
      4  *                             / __| | | | |_) | |
      5  *                            | (__| |_| |  _ <| |___
      6  *                             \___|\___/|_| \_\_____|
      7  *
      8  * Copyright (C) 1998 - 2016, Daniel Stenberg, <daniel (at) 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  * Use the progress callbacks, old and/or new one depending on available
     24  * libcurl version.
     25  * </DESC>
     26  */
     27 #include <stdio.h>
     28 #include <curl/curl.h>
     29 
     30 #define STOP_DOWNLOAD_AFTER_THIS_MANY_BYTES         6000
     31 #define MINIMAL_PROGRESS_FUNCTIONALITY_INTERVAL     3
     32 
     33 struct myprogress {
     34   double lastruntime;
     35   CURL *curl;
     36 };
     37 
     38 /* this is how the CURLOPT_XFERINFOFUNCTION callback works */
     39 static int xferinfo(void *p,
     40                     curl_off_t dltotal, curl_off_t dlnow,
     41                     curl_off_t ultotal, curl_off_t ulnow)
     42 {
     43   struct myprogress *myp = (struct myprogress *)p;
     44   CURL *curl = myp->curl;
     45   double curtime = 0;
     46 
     47   curl_easy_getinfo(curl, CURLINFO_TOTAL_TIME, &curtime);
     48 
     49   /* under certain circumstances it may be desirable for certain functionality
     50      to only run every N seconds, in order to do this the transaction time can
     51      be used */
     52   if((curtime - myp->lastruntime) >= MINIMAL_PROGRESS_FUNCTIONALITY_INTERVAL) {
     53     myp->lastruntime = curtime;
     54     fprintf(stderr, "TOTAL TIME: %f \r\n", curtime);
     55   }
     56 
     57   fprintf(stderr, "UP: %" CURL_FORMAT_CURL_OFF_T " of %" CURL_FORMAT_CURL_OFF_T
     58           "  DOWN: %" CURL_FORMAT_CURL_OFF_T " of %" CURL_FORMAT_CURL_OFF_T
     59           "\r\n",
     60           ulnow, ultotal, dlnow, dltotal);
     61 
     62   if(dlnow > STOP_DOWNLOAD_AFTER_THIS_MANY_BYTES)
     63     return 1;
     64   return 0;
     65 }
     66 
     67 /* for libcurl older than 7.32.0 (CURLOPT_PROGRESSFUNCTION) */
     68 static int older_progress(void *p,
     69                           double dltotal, double dlnow,
     70                           double ultotal, double ulnow)
     71 {
     72   return xferinfo(p,
     73                   (curl_off_t)dltotal,
     74                   (curl_off_t)dlnow,
     75                   (curl_off_t)ultotal,
     76                   (curl_off_t)ulnow);
     77 }
     78 
     79 
     80 int main(void)
     81 {
     82   CURL *curl;
     83   CURLcode res = CURLE_OK;
     84   struct myprogress prog;
     85 
     86   curl = curl_easy_init();
     87   if(curl) {
     88     prog.lastruntime = 0;
     89     prog.curl = curl;
     90 
     91     curl_easy_setopt(curl, CURLOPT_URL, "http://example.com/");
     92 
     93     curl_easy_setopt(curl, CURLOPT_PROGRESSFUNCTION, older_progress);
     94     /* pass the struct pointer into the progress function */
     95     curl_easy_setopt(curl, CURLOPT_PROGRESSDATA, &prog);
     96 
     97 #if LIBCURL_VERSION_NUM >= 0x072000
     98     /* xferinfo was introduced in 7.32.0, no earlier libcurl versions will
     99        compile as they won't have the symbols around.
    100 
    101        If built with a newer libcurl, but running with an older libcurl:
    102        curl_easy_setopt() will fail in run-time trying to set the new
    103        callback, making the older callback get used.
    104 
    105        New libcurls will prefer the new callback and instead use that one even
    106        if both callbacks are set. */
    107 
    108     curl_easy_setopt(curl, CURLOPT_XFERINFOFUNCTION, xferinfo);
    109     /* pass the struct pointer into the xferinfo function, note that this is
    110        an alias to CURLOPT_PROGRESSDATA */
    111     curl_easy_setopt(curl, CURLOPT_XFERINFODATA, &prog);
    112 #endif
    113 
    114     curl_easy_setopt(curl, CURLOPT_NOPROGRESS, 0L);
    115     res = curl_easy_perform(curl);
    116 
    117     if(res != CURLE_OK)
    118       fprintf(stderr, "%s\n", curl_easy_strerror(res));
    119 
    120     /* always cleanup */
    121     curl_easy_cleanup(curl);
    122   }
    123   return (int)res;
    124 }
    125