curl / libcurl / API / Examples / debug.c

debug.c

Download debug.c raw

/***************************************************************************
 *                                  _   _ ____  _
 *  Project                     ___| | | |  _ \| |
 *                             / __| | | | |_) | |
 *                            | (__| |_| |  _ <| |___
 *                             \___|\___/|_| \_\_____|
 *
 * Copyright (C) 1998 - 2016, 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
 * are also available at https://curl.haxx.se/docs/copyright.html.
 *
 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
 * copies of the Software, and permit persons to whom the Software is
 * furnished to do so, under the terms of the COPYING file.
 *
 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
 * KIND, either express or implied.
 *
 ***************************************************************************/ 
/* <DESC>
 * Show how CURLOPT_DEBUGFUNCTION can be used.
 * </DESC>
 */ 
#include <stdio.h>
#include <curl/curl.h>
 
struct data {
  char trace_ascii; /* 1 or 0 */ 
};
 
static
void dump(const char *text,
          FILE *stream, unsigned char *ptr, size_t size,
          char nohex)
{
  size_t i;
  size_t c;
 
  unsigned int width=0x10;
 
  if(nohex)
    /* without the hex output, we can fit more on screen */ 
    width = 0x40;
 
  fprintf(stream, "%s, %10.10ld bytes (0x%8.8lx)\n",
          text, (long)size, (long)size);
 
  for(i=0; i<size; i+= width) {
 
    fprintf(stream, "%4.4lx: ", (long)i);
 
    if(!nohex) {
      /* hex not disabled, show it */ 
      for(c = 0; c < width; c++)
        if(i+c < size)
          fprintf(stream, "%02x ", ptr[i+c]);
        else
          fputs("   ", stream);
    }
 
    for(c = 0; (c < width) && (i+c < size); c++) {
      /* check for 0D0A; if found, skip past and start a new line of output */ 
      if(nohex && (i+c+1 < size) && ptr[i+c]==0x0D && ptr[i+c+1]==0x0A) {
        i+=(c+2-width);
        break;
      }
      fprintf(stream, "%c",
              (ptr[i+c]>=0x20) && (ptr[i+c]<0x80)?ptr[i+c]:'.');
      /* check again for 0D0A, to avoid an extra \n if it's at width */ 
      if(nohex && (i+c+2 < size) && ptr[i+c+1]==0x0D && ptr[i+c+2]==0x0A) {
        i+=(c+3-width);
        break;
      }
    }
    fputc('\n', stream); /* newline */ 
  }
  fflush(stream);
}
 
static
int my_trace(CURL *handle, curl_infotype type,
             char *data, size_t size,
             void *userp)
{
  struct data *config = (struct data *)userp;
  const char *text;
  (void)handle; /* prevent compiler warning */ 
 
  switch(type) {
  case CURLINFO_TEXT:
    fprintf(stderr, "== Info: %s", data);
  default: /* in case a new one is introduced to shock us */ 
    return 0;
 
  case CURLINFO_HEADER_OUT:
    text = "=> Send header";
    break;
  case CURLINFO_DATA_OUT:
    text = "=> Send data";
    break;
  case CURLINFO_SSL_DATA_OUT:
    text = "=> Send SSL data";
    break;
  case CURLINFO_HEADER_IN:
    text = "<= Recv header";
    break;
  case CURLINFO_DATA_IN:
    text = "<= Recv data";
    break;
  case CURLINFO_SSL_DATA_IN:
    text = "<= Recv SSL data";
    break;
  }
 
  dump(text, stderr, (unsigned char *)data, size, config->trace_ascii);
  return 0;
}
 
int main(void)
{
  CURL *curl;
  CURLcode res;
  struct data config;
 
  config.trace_ascii = 1; /* enable ascii tracing */ 
 
  curl = curl_easy_init();
  if(curl) {
    curl_easy_setopt(curl, CURLOPT_DEBUGFUNCTION, my_trace);
    curl_easy_setopt(curl, CURLOPT_DEBUGDATA, &config);
 
    /* the DEBUGFUNCTION has no effect until we enable VERBOSE */ 
    curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L);
 
    /* example.com is redirected, so we tell libcurl to follow redirection */ 
    curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1L);
 
    curl_easy_setopt(curl, CURLOPT_URL, "http://example.com/");
    res = curl_easy_perform(curl);
    /* Check for errors */ 
    if(res != CURLE_OK)
      fprintf(stderr, "curl_easy_perform() failed: %s\n",
              curl_easy_strerror(res));
 
    /* always cleanup */ 
    curl_easy_cleanup(curl);
  }
  return 0;
}