SCARY STUFF

gistfile1.php

function torrent_scrape($torrent_id) {
	$times['start'] = microtime(1);
	$times['last'] = microtime(1);

	$torrents = torrent_get(get_str_build(array('extended' => '', 'torrent_id' => $torrent_id)));
	$times['query'] = microtime(1) - $times['last'];
	$times['last'] = microtime(1);

	// Return if the torrent_id doesn't exist
	if (!isset($torrents) || !is_array($torrents) || !count($torrents)) { return; }

	$torrent = $torrents[0];
	
	// Only scrape torrents every 1800 seconds
	if (($torrent['scrape_time']+1800) > time()) { return; }

	api_ping('torrent_scrape', $torrent_id);

	// This will be set if the user has an external application that runs off the ping API doing scrapes.
	if (isset($config['no_scrape'])) {
		return;
	}

	// The following code is inspired by the Weaboo language setting, because it's stupid and should never be used in production.
	// Hopefully none of this will ever actually be needed.

	// Set this to 1 if you want some verbose output for testing
	$http_debug = 0;

	if ($http_debug) { header('Content-Type: text/plain'); }

	// Set up the scrape array
	$scrape = array();
	$handles = array();
	foreach ($torrent['trackers'] as $tracker_id => $tracker) {
		// Create tracker entry
		$scrape[$tracker_id] = array();

		// Store the ID for later
		$scrape[$tracker_id]['id'] = $tracker_id;

		// See -> http://wiki.theory.org/BitTorrentSpecification#Tracker_.27scrape.27_Convention
		$scrape[$tracker_id]['url'] = sprintf('%s?info_hash=%s', str_replace('announce', 'scrape', $tracker['tracker']), urlencode($torrent['info_hash']));

		// Parse the tracker URL
		$url = parse_url($scrape[$tracker_id]['url']);

		// URL wa warui da yo
		if (!is_array($url) || !count($url) || !isset($url['path'])) {
			unset($scrape[$tracker_id]);
			continue;
		}

		// Stupid parse_url doesn't provide defaults or even empty values
		if (!isset($url['port']))  { $url['port']  = 80; }
		if (!isset($url['query'])) { $url['query'] = ''; }

		// Fix the stupid output from parse_url durr
		$url['path'] = $url['path'].(strlen($url['query']) ? '?'.$url['query'] : '');
		unset($url['query']);
		unset($url['scheme']);
		$scrape[$tracker_id]['url'] = $url;
		unset($url);

		// Build the request
		$scrape[$tracker_id]['req'] = sprintf(
			"GET %s HTTP/1.1\r\nHost: %s:%s\r\nConnection: close\r\nUser-Agent: Jishaku/0.1\r\n\r\n",
			$scrape[$tracker_id]['url']['path'], $scrape[$tracker_id]['url']['host'], $scrape[$tracker_id]['url']['port']
		);

		$scrape[$tracker_id]['response'] = '';
		$scrape[$tracker_id]['headers'] = '';
		$scrape[$tracker_id]['body'] = '';
		$scrape[$tracker_id]['array'] = array();
	}

	$times['setup'] = microtime(1) - $times['last'];
	$times['last'] = microtime(1);

	// Resolve DNS
	foreach ($torrent['trackers'] as $tracker_id => $tracker) {
		if (!isset($scrape[$tracker_id])) { continue; }
		
		if ($http_debug) { printf("init: getting ip for %s\n", $tracker['tracker']); flush(); }

		$dns = dns_get_record($scrape[$tracker_id]['url']['host'], DNS_A);
		if (is_array($dns) && count($dns)) {
			if ($http_debug) { printf("init: got ip for %s (%s)\n", $tracker['tracker'], $dns[0]['ip']); flush(); }
			$scrape[$tracker_id]['url']['ip'] = $dns[0]['ip'];
		} else {
			if ($http_debug) { printf("init: couldn't get ip for %s\n", $tracker['tracker']); flush(); }
			unset($scrape[$tracker_id]);
		}
	}

	$times['dns'] = microtime(1) - $times['last'];
	$times['last'] = microtime(1);

	// Open the sockets
	foreach ($torrent['trackers'] as $tracker_id => $tracker) {
		if (!isset($scrape[$tracker_id])) { continue; }

		if ($http_debug) { printf("init: opening socket for %s\n", $tracker['tracker']); flush(); }

		$scrape[$tracker_id]['sent'] = 0;
		$scrape[$tracker_id]['read'] = 0;
		$scrape[$tracker_id]['error'] = 0;

		$scrape[$tracker_id]['fh'] = @stream_socket_client(sprintf("tcp://%s:%s", $scrape[$tracker_id]['url']['ip'], $scrape[$tracker_id]['url']['port']), $errno, $errstr, 0, STREAM_CLIENT_ASYNC_CONNECT);
		$handles[(int)$scrape[$tracker_id]['fh']] = $tracker_id;
	}

	$times['open-sockets'] = microtime(1) - $times['last'];
	$times['last'] = microtime(1);

	$http_timeout = 15;
	$http_start   = time();

	// Read stuff for $http_timeout seconds
	while (time() < ($http_start + $http_timeout)) {
		list($read, $write, $error) = array(array(), array(), array());

		foreach ($torrent['trackers'] as $tracker_id => $tracker) {
			if (!isset($scrape[$tracker_id])) { continue; }

			if (!$scrape[$tracker_id]['sent']) {
				if (@ftell($scrape[$tracker_id]['fh']) !== false) { $write[] = $scrape[$tracker_id]['fh']; }
			} elseif (!$scrape[$tracker_id]['read']) {
				if (@ftell($scrape[$tracker_id]['fh']) !== false) { $read[] = $scrape[$tracker_id]['fh']; }
			}

			// TODO: This might be bad?
			// BUG:0000039
			if (@ftell($scrape[$tracker_id]['fh']) !== false) { $error[] = $scrape[$tracker_id]['fh']; }
		}

		if (!count($read) && !count($write)) { break; }

		stream_select($read, $write, $error, 1);

		if ($http_debug) {
			printf("http: %s sockets ready for reading\n", count($read));
			printf("http: %s sockets ready for writing\n", count($write));
			printf("http: %s sockets with errors\n", count($error));
			flush();
		}

		foreach ($error as $fh) {
			if (!isset($handles[(int)$fh])) { continue; }

			$tracker_id = $handles[(int)$fh];
			$tracker = $torrent['trackers'][$tracker_id];

			if ($http_debug) { printf("http: error on %s\n", $tracker['tracker']); flush(); }

			fclose($fh);

			//unset($scrape[$tracker_id]);
			//unset($handles[$fh]);
		}

		foreach ($read as $fh) {
			if (!isset($handles[(int)$fh])) { continue; }

			$tracker_id = $handles[(int)$fh];
			$tracker = $torrent['trackers'][$tracker_id];

			if ($http_debug) { printf("http: activity on %s\n", $tracker['tracker']); flush(); }

			if (($buf = @fread($scrape[$tracker_id]['fh'], 1024)) != false) {
				if ($http_debug) { printf("http: read %s bytes from %s\n", strlen($buf), $tracker['tracker']); flush(); }
				$scrape[$tracker_id]['response'] .= $buf;
			} else {
				if ($http_debug) { printf("http: closed socket for %s\n", $tracker['tracker']); flush(); }
				@fclose($scrape[$tracker_id]['fh']);
				$scrape[$tracker_id]['read'] = 1;
			}
		}

		foreach ($write as $fh) {
			if (!isset($handles[(int)$fh])) { continue; }

			$tracker_id = $handles[(int)$fh];
			$tracker = $torrent['trackers'][$tracker_id];

			if ($http_debug) { printf("http: ready to write on %s\n", $tracker['tracker']); flush(); }

			if (!$scrape[$tracker_id]['sent']) {
				if (@fwrite($scrape[$tracker_id]['fh'], $scrape[$tracker_id]['req']) === false) {
					unset($scrape[$tracker_id]);
					unset($handles[(int)$fh]);
					continue;
				}

				$scrape[$tracker_id]['sent'] = 1;
			}
		}
	}

	$times['http'] = microtime(1) - $times['last'];
	$times['last'] = microtime(1);

	unset($handles);

	// Split the headers/body of the HTTP response
	foreach ($torrent['trackers'] as $tracker_id => $tracker) {
		// Only try to parse stuff that exists still
		if (isset($scrape[$tracker_id]) && isset($scrape[$tracker_id]['response']) && strlen($scrape[$tracker_id]['response']) && preg_match('/\r\n\r\n/', $scrape[$tracker_id]['response'])) {
			list($scrape[$tracker_id]['headers'], $scrape[$tracker_id]['body']) = explode("\r\n\r\n", $scrape[$tracker_id]['response'], 2);
		} elseif (isset($scrape[$tracker_id])) {
			unset($scrape[$tracker_id]);
		}
	}

	$times['split'] = microtime(1) - $times['last'];
	$times['last'] = microtime(1);

	// Parse stuff
	foreach ($torrent['trackers'] as $tracker_id => $tracker) {
		// Only try to parse stuff that exists still (kyon-kun, denwa)
		if (isset($scrape[$tracker_id]) && isset($scrape[$tracker_id]['body']) && strlen($scrape[$tracker_id]['body'])) {
			$scrape[$tracker_id]['array'] = torrent_parse($scrape[$tracker_id]['body']);
		}

		// If it didn't parse properly, discard it
		if (!isset($scrape[$tracker_id]['array']) || !is_array($scrape[$tracker_id]['array']) || !count($scrape[$tracker_id]['array'])) {
			if ($http_debug) { printf("parse: couldn't parse data for %s\n", $tracker['tracker']); flush(); }
			unset($scrape[$tracker_id]);
		} else {
			if ($http_debug) {
				printf("parse: parsed data for %s\n", $tracker['tracker']); flush();
				$scrape[$tracker_id]['response'] = '<removed>';
			}
		}
	}

	$times['parse'] = microtime(1) - $times['last'];
	$times['last'] = microtime(1);

	$times['total'] = microtime(1) - $times['start'];

	unset($times['last']);
	unset($times['start']);

	if ($http_debug) {
		var_dump($scrape);
		var_dump($times);
		exit();
	}

	foreach ($torrent['trackers'] as $tracker_id => $tracker) {
		if (!isset($scrape[$tracker_id])) { continue; }

		$stats = array_shift($scrape[$tracker_id]['array']['files']);

		$torrents_trackers_update_query = sprintf(
			"UPDATE `torrents_trackers` SET `scrape_time` = %d, `seeds` = %d, `leechers` = %d, `completed` = %d WHERE `torrent_id` = %d AND `tracker_id` = %d LIMIT 1;",
			time(), $stats['complete'], $stats['incomplete'], $stats['downloaded'], $torrent['torrent_id'], $tracker_id
		);

		$torrents_update_query = sprintf(
			"UPDATE `torrents` SET `scrape_time` = %d, `seeds` = (SELECT MAX(`seeds`) FROM `torrents_trackers` WHERE `torrent_id` = %d LIMIT 1), `leechers` = (SELECT MAX(`leechers`) FROM `torrents_trackers` WHERE `torrent_id` = %d LIMIT 1), `completed` = (SELECT MAX(`completed`) FROM `torrents_trackers` WHERE `torrent_id` = %d LIMIT 1) WHERE `torrent_id` = %d LIMIT 1;",
			time(), $torrent_id, $torrent_id, $torrent_id, $torrent_id
		);

		mysql_query($torrents_trackers_update_query);
		mysql_query($torrents_update_query);
	}
}