/*
 * get_http.c-v0.9:
 *   get_http is a simple libcurl-based http client that will display headers
 *   and/or body from a web server.
 *
 * Requirements:
 *   libcurl - http://curl.haxx.se/
 *
 * Compiling:
 *   gcc -Wall -O2 `curl-config --cflags` get_http.c -o get_http \
 *     `curl-config --libs`
 *
 * Usage:
 *   see get_http -h
 *
 *   # displays headers only, follows redirects
 *   get_http -Hf http://www.gozer.org/
 *
 *   # execute a request with a specific user-agent id or string (see help)
 *   get_http -a 0 msn.com
 *   get_http -a "Dancin' Jackson 2.0!" https://have.bigger.for-you.com
 *
 *   # run a request on a protected site
 *   get_http -u user:pass http://staff.example.com/
 *
 * (c) 2003-2006 Mike Hokenson <logan at dct dot com>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <getopt.h>

#include <curl/curl.h>
#include <curl/types.h>
#include <curl/easy.h>

#define _VERSION "0.9"
#define _HOME    "http://www.gozer.org/programs/c/"

#ifndef isdigit
#define isdigit(c) (((c) >= '0') && ((c) <= '9'))
#endif

#define _N_ELEMENTS(s) (sizeof(s) / sizeof((s)[0]))

typedef struct {
  const char *key;
  const char *val;
} UserAgent;

UserAgent useragent_map[] = {
  {
    "Internet Explorer 6.0 (Windows XP)",
    "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1)"
  },
  {
    "Internet Explorer 5.1 (Mac OS)",
    "Mozilla/4.0 (compatible; MSIE 5.15; Mac_PowerPC)"
  },
  {
    "Mozilla Firefox 1.5.0.6 (Windows XP)",
    "Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.0.6) Gecko/20060728 Firefox/1.5.0.6"
  },
  {
    "Mozilla Firefox 1.5.0.6 (Linux)",
    "Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.8.0.6) Gecko/20060728 Firefox/1.5.0.6"
  },
  {
    "Mozilla 1.7.13 (Windows XP)",
    "Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.7.13) Gecko/20060414",
  },
  {
    "Mozilla 1.7.13 (Linux)",
    "Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.13) Gecko/20060417"
  },
  {
    "Opera 9.01 (Windows XP)",
    "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; en) Opera 9.01"
  },
  {
    "Opera 9.01 (Linux)",
    "Mozilla/4.0 (compatible; MSIE 6.0; X11; Linux i686; en) Opera 9.01"
  },
  {
    "Opera 8.52 (Windows XP)",
    "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; en) Opera 8.52"
  },
  {
    "Opera 8.52 (Linux)",
    "Mozilla/4.0 (compatible; MSIE 6.0; X11; Linux i686; en) Opera 8.52"
  },
  {
    "Safari 2.0.3 (Mac OS X 10.4.5)",
    "Mozilla/5.0 (Macintosh; U; PPC Mac OS X; en) AppleWebKit/418 (KHTML, like Gecko) Safari/417.9.3"
  },
  {
    "Safari 1.0 (Mac OS X)",
    "Mozilla/5.0 (Macintosh; U; PPC Mac OS X; en-us) AppleWebKit/85 (KHTML, like Gecko) Safari/85"
  },
  {
    "Konqueror 3.4 (Linux)",
    "Mozilla/5.0 (compatible; Konqueror/3.4; Linux) KHTML/3.4.0 (like Gecko)"
  },
  {
    "Netscape 4.8 (Windows XP)",
    "Mozilla/4.8 [en] (Windows NT 5.1; U)"
  },
  {
    "Netscape 4.8 (Linux)",
    "Mozilla/4.8 [en] (X11; U; Linux 2.6.17 i686)"
  },
  {
    "OmniWeb 4.2.1 (Mac OS)",
    "Mozilla/4.5 (compatible; OmniWeb/4.2.1-v435.9; Mac_PowerPC)"
  },
  {
    "WebTV",
    "Mozilla/4.0 WebTV/2.6 (compatible; MSIE 4.0)"
  },
  {
    "Googlebot",
    "Googlebot/2.1 (+http://www.googlebot.com/bot.html)"
  },
  {
    "MSNBot",
    "msnbot/0.1 (+http://search.msn.com/msnbot.htm)"
  },
  {
    NULL,
    NULL
  }
};

void show_help(void)
{
  int i;

  fprintf(stderr, "Usage: get_http [OPTS] [URL1 URL2 ...]\n");

  fprintf(stderr, "  OPTS:\n");
  fprintf(stderr, "    -a [id/string]  set user-agent by id or string\n");
  fprintf(stderr, "    -b              display response body only\n");
  fprintf(stderr, "    -f              follow Location: redirects\n");
  fprintf(stderr, "    -h              display help\n");
  fprintf(stderr, "    -H              display response headers only\n");
  fprintf(stderr, "    -r [referrer]   send HTTP referrer\n");
  fprintf(stderr, "    -t [timeout]    set overall connection timeout\n");
  fprintf(stderr, "    -T              enable transaction timer\n");
  fprintf(stderr, "    -u [user:pass]  set authentication credentials\n");
  fprintf(stderr, "    -v              make verbose (libcurl)\n");
  fprintf(stderr, "    -V              display version\n\n");

  fprintf(stderr, "  Builtin agents:\n");

  for (i = 0; useragent_map[i].key; i++)
    fprintf(stderr, "    %2d: %s\n", i, useragent_map[i].key);
}

int str_is_digit(const char *str, int *val)
{
  const char *p;

  if (!str)
      return 0;

  for (p = str; *p; p++)
    if (!isdigit(*p))
      return 0;

  if (val)
    *val = atoi(str);

  return 1;
}

int main(int argc, char **argv)
{
  int option, timer = 0;

  CURL *curl;

  char error[CURL_ERROR_SIZE];

  if (!(curl = curl_easy_init())) {
      fprintf(stderr, "Unable to initialize curl\n");
      exit(1);
  }

  curl_easy_setopt(curl, CURLOPT_HEADER, 1);
  curl_easy_setopt(curl, CURLOPT_NOPROGRESS, 1);
  curl_easy_setopt(curl, CURLOPT_TRANSFERTEXT, 1);

  curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 0);
  curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 0);

  curl_easy_setopt(curl, CURLOPT_ERRORBUFFER, error);

  while ((option = getopt(argc, argv, "a:bfhHr:t:Tu:vV")) != EOF) {
    switch (option) {
      case 'a':
        {
          const char *agent = NULL;

          int id;

          if (str_is_digit(optarg, &id)) {
            if (id >= 0 && id < _N_ELEMENTS(useragent_map))
              agent = useragent_map[id].val;
          } else
            agent = optarg;

          if (agent)
            curl_easy_setopt(curl, CURLOPT_USERAGENT, agent);
        }

        break;
      case 'b':
        curl_easy_setopt(curl, CURLOPT_HEADER, 0);
        curl_easy_setopt(curl, CURLOPT_NOBODY, 0);
        break;
      case 'f':
        curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1);
        break;
      case 'h':
        show_help();
        exit(0);
      case 'H':
        curl_easy_setopt(curl, CURLOPT_HEADER, 1);
        curl_easy_setopt(curl, CURLOPT_NOBODY, 1);
        break;
      case 'r':
        curl_easy_setopt(curl, CURLOPT_REFERER, optarg);
        break;
      case 't':
        {
          int timeout;

          if (!str_is_digit(optarg, &timeout)) {
            show_help();
            exit(1);
          }

          curl_easy_setopt(curl, CURLOPT_TIMEOUT, timeout);
        }
        break;
      case 'T':
        timer = 1;
        break;
      case 'u':
        curl_easy_setopt(curl, CURLOPT_USERPWD, optarg);
        break;
      case 'v':
        curl_easy_setopt(curl, CURLOPT_VERBOSE, 1);
        break;
      case 'V':
        fprintf(stderr, "get_http/%s (%s)\n", _VERSION, _HOME);
        exit(0);
      default:
        show_help();
        exit(1);
    }
  }

  if (optind >= argc) {
    show_help();
    exit(1);
  }

  while (optind < argc) {
    const char *uri = argv[optind++];

    error[0] = '\0';

    curl_easy_setopt(curl, CURLOPT_URL, uri);

    if (curl_easy_perform(curl) == CURLE_OK) {
      if (timer) {
        double s;

        curl_easy_getinfo(curl, CURLINFO_TOTAL_TIME, &s);

        fprintf(stdout, "Time: %0.3fs\n\n", s);
      }
    } else
      fprintf(stderr, "%s: %s\n\n", uri, (error[0]) ? error : "Unknown Error");
  }

  curl_easy_cleanup(curl);

  exit(0);
}

/*
 * --- Changelog --------------------------------------------------------------
 *
 * 0.1 - 2003/06/26:
 *   initial release.
 *
 * 0.2 - 2003/06/27:
 *   added -o, errors are displayed in red, reworked and updated User-Agents
 *
 * 0.3 - 2003/06/30:
 *   added resolver and http status stats, individual colors for each stats
 *     item.
 *
 * 0.4 - 2003/07/24:
 *   resume transfers (-r), quiet mode (-q), referrer (-R), authentication
 *     (-U), added Safari, Firebird, and WebTV UA's, example usage.
 *
 * 0.5 - 2003/07/29:
 *   added more ugliness to download filename handling, added callback to
 *     check for HTTP Content-Disposition: attachment; filename="..." header,
 *     try to include the pathname in the default file (replace / with _).
 *
 * 0.6 - 2004/04/27:
 *   reverted to a more simple application: removed stats, file downloads,
 *     and other nonsense.
 *   changed default user-agent from IE6 to CURL's default.
 *   don't verify ssl certs.
 *   now under a BSD license.
 *
 * 0.7 - 2004/06/24:
 *   added -b (body only).
 *   updated usage, added missing -V option.
 *
 * 0.8 - 2006/08/09:
 *   switch changes (-R to -r, -V to -d, -u to -a, -U to -u)
 *   agent overhaul
 *
 * 0.9 - 2006/12/13:
 *   add timer (-T), which displays the duration of each request (in seconds)
 *   more switch changes (-v to -V, -d to -v)
 *
 * --- Changelog --------------------------------------------------------------
 */