curl / libcurl / API / Examples / progressfunc.c

progressfunc.c

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 * Copyright (C) 1998 - 2021, Daniel Stenberg, <daniel@haxx.se>, et al.
 *
 * This software is licensed as described in the file COPYING, which
 * you should have received as part of this distribution. The terms
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 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
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 * furnished to do so, under the terms of the COPYING file.
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 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
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/* <DESC>
 * Use the progress callbacks, old and/or new one depending on available
 * libcurl version.
 * </DESC>
 */
#include <stdio.h>
#include <curl/curl.h>
 
#define MINIMAL_PROGRESS_FUNCTIONALITY_INTERVAL     3000000
#define STOP_DOWNLOAD_AFTER_THIS_MANY_BYTES         6000
 
struct myprogress {
  curl_off_t lastruntime; /* type depends on version, see above */
  CURL *curl;
};
 
/* this is how the CURLOPT_XFERINFOFUNCTION callback works */
static int xferinfo(void *p,
                    curl_off_t dltotal, curl_off_t dlnow,
                    curl_off_t ultotal, curl_off_t ulnow)
{
  struct myprogress *myp = (struct myprogress *)p;
  CURL *curl = myp->curl;
  curl_off_t curtime = 0;
 
  curl_easy_getinfo(curl, CURLINFO_TOTAL_TIME_T, &curtime);
 
  /* under certain circumstances it may be desirable for certain functionality
     to only run every N seconds, in order to do this the transaction time can
     be used */
  if((curtime - myp->lastruntime) >= MINIMAL_PROGRESS_FUNCTIONALITY_INTERVAL) {
    myp->lastruntime = curtime;
    fprintf(stderr, "TOTAL TIME: %lu.%06lu\r\n",
            (unsigned long)(curtime / 1000000),
            (unsigned long)(curtime % 1000000));
  }
 
  fprintf(stderr, "UP: %lu of %lu  DOWN: %lu of %lu\r\n",
          (unsigned long)ulnow, (unsigned long)ultotal,
          (unsigned long)dlnow, (unsigned long)dltotal);
 
  if(dlnow > STOP_DOWNLOAD_AFTER_THIS_MANY_BYTES)
    return 1;
  return 0;
}
 
int main(void)
{
  CURL *curl;
  CURLcode res = CURLE_OK;
  struct myprogress prog;
 
  curl = curl_easy_init();
  if(curl) {
    prog.lastruntime = 0;
    prog.curl = curl;
 
    curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
 
    curl_easy_setopt(curl, CURLOPT_XFERINFOFUNCTION, xferinfo);
    /* pass the struct pointer into the xferinfo function */
    curl_easy_setopt(curl, CURLOPT_XFERINFODATA, &prog);
 
    curl_easy_setopt(curl, CURLOPT_NOPROGRESS, 0L);
    res = curl_easy_perform(curl);
 
    if(res != CURLE_OK)
      fprintf(stderr, "%s\n", curl_easy_strerror(res));
 
    /* always cleanup */
    curl_easy_cleanup(curl);
  }
  return (int)res;
}