Return to progressfunc.c CVS log

Up to [ELWIX - Embedded LightWeight unIX -] / embedaddon / curl / docs / examples

curl

    1: /***************************************************************************
    2:  *                                  _   _ ____  _
    3:  *  Project                     ___| | | |  _ \| |
    4:  *                             / __| | | | |_) | |
    5:  *                            | (__| |_| |  _ <| |___
    6:  *                             \___|\___/|_| \_\_____|
    7:  *
    8:  * Copyright (C) 1998 - 2018, 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:  * 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: #if LIBCURL_VERSION_NUM >= 0x073d00
   31: /* In libcurl 7.61.0, support was added for extracting the time in plain
   32:    microseconds. Older libcurl versions are stuck in using 'double' for this
   33:    information so we complicate this example a bit by supporting either
   34:    approach. */
   35: #define TIME_IN_US 1 /* microseconds */
   36: #define TIMETYPE curl_off_t
   37: #define TIMEOPT CURLINFO_TOTAL_TIME_T
   38: #define MINIMAL_PROGRESS_FUNCTIONALITY_INTERVAL     3000000
   39: #else
   40: #define TIMETYPE double
   41: #define TIMEOPT CURLINFO_TOTAL_TIME
   42: #define MINIMAL_PROGRESS_FUNCTIONALITY_INTERVAL     3
   43: #endif
   44: 
   45: #define STOP_DOWNLOAD_AFTER_THIS_MANY_BYTES         6000
   46: 
   47: struct myprogress {
   48:   TIMETYPE lastruntime; /* type depends on version, see above */
   49:   CURL *curl;
   50: };
   51: 
   52: /* this is how the CURLOPT_XFERINFOFUNCTION callback works */
   53: static int xferinfo(void *p,
   54:                     curl_off_t dltotal, curl_off_t dlnow,
   55:                     curl_off_t ultotal, curl_off_t ulnow)
   56: {
   57:   struct myprogress *myp = (struct myprogress *)p;
   58:   CURL *curl = myp->curl;
   59:   TIMETYPE curtime = 0;
   60: 
   61:   curl_easy_getinfo(curl, TIMEOPT, &curtime);
   62: 
   63:   /* under certain circumstances it may be desirable for certain functionality
   64:      to only run every N seconds, in order to do this the transaction time can
   65:      be used */
   66:   if((curtime - myp->lastruntime) >= MINIMAL_PROGRESS_FUNCTIONALITY_INTERVAL) {
   67:     myp->lastruntime = curtime;
   68: #ifdef TIME_IN_US
   69:     fprintf(stderr, "TOTAL TIME: %" CURL_FORMAT_CURL_OFF_T ".%06ld\r\n",
   70:             (curtime / 1000000), (long)(curtime % 1000000));
   71: #else
   72:     fprintf(stderr, "TOTAL TIME: %f \r\n", curtime);
   73: #endif
   74:   }
   75: 
   76:   fprintf(stderr, "UP: %" CURL_FORMAT_CURL_OFF_T " of %" CURL_FORMAT_CURL_OFF_T
   77:           "  DOWN: %" CURL_FORMAT_CURL_OFF_T " of %" CURL_FORMAT_CURL_OFF_T
   78:           "\r\n",
   79:           ulnow, ultotal, dlnow, dltotal);
   80: 
   81:   if(dlnow > STOP_DOWNLOAD_AFTER_THIS_MANY_BYTES)
   82:     return 1;
   83:   return 0;
   84: }
   85: 
   86: #if LIBCURL_VERSION_NUM < 0x072000
   87: /* for libcurl older than 7.32.0 (CURLOPT_PROGRESSFUNCTION) */
   88: static int older_progress(void *p,
   89:                           double dltotal, double dlnow,
   90:                           double ultotal, double ulnow)
   91: {
   92:   return xferinfo(p,
   93:                   (curl_off_t)dltotal,
   94:                   (curl_off_t)dlnow,
   95:                   (curl_off_t)ultotal,
   96:                   (curl_off_t)ulnow);
   97: }
   98: #endif
   99: 
  100: int main(void)
  101: {
  102:   CURL *curl;
  103:   CURLcode res = CURLE_OK;
  104:   struct myprogress prog;
  105: 
  106:   curl = curl_easy_init();
  107:   if(curl) {
  108:     prog.lastruntime = 0;
  109:     prog.curl = curl;
  110: 
  111:     curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
  112: 
  113: #if LIBCURL_VERSION_NUM >= 0x072000
  114:     /* xferinfo was introduced in 7.32.0, no earlier libcurl versions will
  115:        compile as they won't have the symbols around.
  116: 
  117:        If built with a newer libcurl, but running with an older libcurl:
  118:        curl_easy_setopt() will fail in run-time trying to set the new
  119:        callback, making the older callback get used.
  120: 
  121:        New libcurls will prefer the new callback and instead use that one even
  122:        if both callbacks are set. */
  123: 
  124:     curl_easy_setopt(curl, CURLOPT_XFERINFOFUNCTION, xferinfo);
  125:     /* pass the struct pointer into the xferinfo function, note that this is
  126:        an alias to CURLOPT_PROGRESSDATA */
  127:     curl_easy_setopt(curl, CURLOPT_XFERINFODATA, &prog);
  128: #else
  129:     curl_easy_setopt(curl, CURLOPT_PROGRESSFUNCTION, older_progress);
  130:     /* pass the struct pointer into the progress function */
  131:     curl_easy_setopt(curl, CURLOPT_PROGRESSDATA, &prog);
  132: #endif
  133: 
  134:     curl_easy_setopt(curl, CURLOPT_NOPROGRESS, 0L);
  135:     res = curl_easy_perform(curl);
  136: 
  137:     if(res != CURLE_OK)
  138:       fprintf(stderr, "%s\n", curl_easy_strerror(res));
  139: 
  140:     /* always cleanup */
  141:     curl_easy_cleanup(curl);
  142:   }
  143:   return (int)res;
  144: }