index.php

   1 <?php
   2 // Shaarli 0.0.45beta - Shaare your links...
   3 // The personal, minimalist, super-fast, no-database Delicious clone. By sebsauvage.net
   4 // http://sebsauvage.net/wiki/doku.php?id=php:shaarli
   5 // Licence: http://www.opensource.org/licenses/zlib-license.php
   6 // Requires: PHP 5.1.x  (but autocomplete fields will only work if you have PHP 5.2.x)
   7 // -----------------------------------------------------------------------------------------------
   8 // NEVER TRUST IN PHP.INI
   9 // Some hosts do not define a default timezone in php.ini,
  10 // so we have to do this for avoid the strict standard error.
  11 date_default_timezone_set('UTC');
  12
  13 // -----------------------------------------------------------------------------------------------
  14 // Hardcoded parameter (These parameters can be overwritten by creating the file /data/options.php)
  15 $GLOBALS['config']['DATADIR'] = 'data'; // Data subdirectory
  16 $GLOBALS['config']['CONFIG_FILE'] = $GLOBALS['config']['DATADIR'].'/config.php'; // Configuration file (user login/password)
  17 $GLOBALS['config']['DATASTORE'] = $GLOBALS['config']['DATADIR'].'/datastore.php'; // Data storage file.
  18 $GLOBALS['config']['LINKS_PER_PAGE'] = 20; // Default links per page.
  19 $GLOBALS['config']['IPBANS_FILENAME'] = $GLOBALS['config']['DATADIR'].'/ipbans.php'; // File storage for failures and bans.
  20 $GLOBALS['config']['BAN_AFTER'] = 4;        // Ban IP after this many failures.
  21 $GLOBALS['config']['BAN_DURATION'] = 1800;  // Ban duration for IP address after login failures (in seconds) (1800 sec. = 30 minutes)
  22 $GLOBALS['config']['OPEN_SHAARLI'] = false; // If true, anyone can add/edit/delete links without having to login
  23 $GLOBALS['config']['HIDE_TIMESTAMPS'] = false; // If true, the moment when links were saved are not shown to users that are not logged in.
  24 $GLOBALS['config']['SHOW_ATOM'] = false; // If true, an extra "ATOM feed" button will be displayed in the toolbar
  25 $GLOBALS['config']['ENABLE_THUMBNAILS'] = true; // Enable thumbnails in links.
  26 $GLOBALS['config']['CACHEDIR'] = 'cache'; // Cache directory for thumbnails for SLOW services (like flickr)
  27 $GLOBALS['config']['PAGECACHE'] = 'pagecache'; // Page cache directory.
  28 $GLOBALS['config']['ENABLE_LOCALCACHE'] = true; // Enable Shaarli to store thumbnail in a local cache. Disable to reduce web space usage.
  29 $GLOBALS['config']['PUBSUBHUB_URL'] = ''; // PubSubHubbub support. Put an empty string to disable, or put your hub url here to enable.
  30 $GLOBALS['config']['RAINTPL_TMP'] = 'tmp/' ; // Raintpl cache directory  (keep the trailing slash!)
  31 $GLOBALS['config']['RAINTPL_TPL'] = 'tpl/' ; // Raintpl template directory (keep the trailing slash!)
  32 $GLOBALS['config']['UPDATECHECK_FILENAME'] = $GLOBALS['config']['DATADIR'].'/lastupdatecheck.txt'; // For updates check of Shaarli.
  33 $GLOBALS['config']['UPDATECHECK_INTERVAL'] = 86400 ; // Updates check frequency for Shaarli. 86400 seconds=24 hours
  34                                           // Note: You must have publisher.php in the same directory as Shaarli index.php
  35 $GLOBALS['config']['ARCHIVE_ORG'] = false; // For each link, add a link to an archived version on archive.org
  36 $GLOBALS['config']['ENABLE_RSS_PERMALINKS'] = true;  // Enable RSS permalinks by default. This corresponds to the default behavior of shaarli before this was added as an option.
  37 $GLOBALS['config']['HIDE_PUBLIC_LINKS'] = false;
  38 // -----------------------------------------------------------------------------------------------
  39 // You should not touch below (or at your own risks!)
  40 // Optional config file.
  41 if (is_file($GLOBALS['config']['DATADIR'].'/options.php')) require($GLOBALS['config']['DATADIR'].'/options.php');
  42
  43 define('shaarli_version','0.0.45beta');
  44 define('PHPPREFIX','<?php /* '); // Prefix to encapsulate data in PHP code.
  45 define('PHPSUFFIX',' */ ?>'); // Suffix to encapsulate data in PHP code.
  46 // http://server.com/x/shaarli --> /shaarli/
  47 define('WEB_PATH', substr($_SERVER["REQUEST_URI"], 0, 1+strrpos($_SERVER["REQUEST_URI"], '/', 0)));
  48
  49 // Force cookie path (but do not change lifetime)
  50 $cookie=session_get_cookie_params();
  51 $cookiedir = ''; if(dirname($_SERVER['SCRIPT_NAME'])!='/') $cookiedir=dirname($_SERVER["SCRIPT_NAME"]).'/';
  52 session_set_cookie_params($cookie['lifetime'],$cookiedir,$_SERVER['SERVER_NAME']); // Set default cookie expiration and path.
  53
  54 // Set session parameters on server side.
  55 define('INACTIVITY_TIMEOUT',3600); // (in seconds). If the user does not access any page within this time, his/her session is considered expired.
  56 ini_set('session.use_cookies', 1);       // Use cookies to store session.
  57 ini_set('session.use_only_cookies', 1);  // Force cookies for session (phpsessionID forbidden in URL).
  58 ini_set('session.use_trans_sid', false); // Prevent PHP form using sessionID in URL if cookies are disabled.
  59 session_name('shaarli');
  60 if (session_id() == '') session_start();  // Start session if needed (Some server auto-start sessions).
  61
  62 // PHP Settings
  63 ini_set('max_input_time','60');  // High execution time in case of problematic imports/exports.
  64 ini_set('memory_limit', '128M');  // Try to set max upload file size and read (May not work on some hosts).
  65 ini_set('post_max_size', '16M');
  66 ini_set('upload_max_filesize', '16M');
  67 checkphpversion();
  68 error_reporting(E_ALL^E_WARNING);  // See all error except warnings.
  69 //error_reporting(-1); // See all errors (for debugging only)
  70
  71 // Shaarli library
  72 require_once 'application/LinkDB.php';
  73 require_once 'application/Utils.php';
  74
  75 include "inc/rain.tpl.class.php"; //include Rain TPL
  76 raintpl::$tpl_dir = $GLOBALS['config']['RAINTPL_TPL']; // template directory
  77 raintpl::$cache_dir = $GLOBALS['config']['RAINTPL_TMP']; // cache directory
  78
  79 ob_start();  // Output buffering for the page cache.
  80
  81
  82 // In case stupid admin has left magic_quotes enabled in php.ini:
  83 if (get_magic_quotes_gpc())
  84 {
  85     function stripslashes_deep($value) { $value = is_array($value) ? array_map('stripslashes_deep', $value) : stripslashes($value); return $value; }
  86     $_POST = array_map('stripslashes_deep', $_POST);
  87     $_GET = array_map('stripslashes_deep', $_GET);
  88     $_COOKIE = array_map('stripslashes_deep', $_COOKIE);
  89 }
  90
  91 // Prevent caching on client side or proxy: (yes, it's ugly)
  92 header("Last-Modified: " . gmdate("D, d M Y H:i:s") . " GMT");
  93 header("Cache-Control: no-store, no-cache, must-revalidate");
  94 header("Cache-Control: post-check=0, pre-check=0", false);
  95 header("Pragma: no-cache");
  96
  97 // Directories creations (Note that your web host may require different rights than 705.)
  98 if (!is_writable(realpath(dirname(__FILE__)))) die('<pre>ERROR: Shaarli does not have the right to write in its own directory.</pre>');
  99
 100 // Handling of old config file which do not have the new parameters.
 101 if (empty($GLOBALS['title'])) $GLOBALS['title']='Shared links on '.escape(indexUrl());
 102 if (empty($GLOBALS['timezone'])) $GLOBALS['timezone']=date_default_timezone_get();
 103 if (empty($GLOBALS['redirector'])) $GLOBALS['redirector']='';
 104 if (empty($GLOBALS['disablesessionprotection'])) $GLOBALS['disablesessionprotection']=false;
 105 if (empty($GLOBALS['disablejquery'])) $GLOBALS['disablejquery']=false;
 106 if (empty($GLOBALS['privateLinkByDefault'])) $GLOBALS['privateLinkByDefault']=false;
 107 if (empty($GLOBALS['titleLink'])) $GLOBALS['titleLink']='?';
 108 // I really need to rewrite Shaarli with a proper configuation manager.
 109
 110 // Run config screen if first run:
 111 if (!is_file($GLOBALS['config']['CONFIG_FILE'])) install();
 112
 113 require $GLOBALS['config']['CONFIG_FILE'];  // Read login/password hash into $GLOBALS.
 114 $GLOBALS['title'] = !empty($GLOBALS['title']) ? escape($GLOBALS['title']) : '';
 115 $GLOBALS['titleLink'] = !empty($GLOBALS['titleLink']) ? escape($GLOBALS['titleLink']) : '';
 116 $GLOBALS['redirector'] = !empty($GLOBALS['redirector']) ? escape($GLOBALS['redirector']) : '';
 117
 118 // a token depending of deployment salt, user password, and the current ip
 119 define('STAY_SIGNED_IN_TOKEN', sha1($GLOBALS['hash'].$_SERVER["REMOTE_ADDR"].$GLOBALS['salt']));
 120
 121 autoLocale(); // Sniff browser language and set date format accordingly.
 122 header('Content-Type: text/html; charset=utf-8'); // We use UTF-8 for proper international characters handling.
 123
 124 //==================================================================================================
 125 // Checking session state (i.e. is the user still logged in)
 126 //==================================================================================================
 127
 128 function setup_login_state() {
 129         $userIsLoggedIn = false; // By default, we do not consider the user as logged in;
 130         $loginFailure = false; // If set to true, every attempt to authenticate the user will fail. This indicates that an important condition isn't met.
 131         if ($GLOBALS['config']['OPEN_SHAARLI']) {
 132             $userIsLoggedIn = true;
 133         }
 134         if (!isset($GLOBALS['login'])) {
 135             $userIsLoggedIn = false;  // Shaarli is not configured yet.
 136             $loginFailure = true;
 137         }
 138         if (isset($_COOKIE['shaarli_staySignedIn']) &&
 139             $_COOKIE['shaarli_staySignedIn']===STAY_SIGNED_IN_TOKEN &&
 140             !$loginFailure)
 141         {
 142             fillSessionInfo();
 143             $userIsLoggedIn = true;
 144         }
 145         // If session does not exist on server side, or IP address has changed, or session has expired, logout.
 146         if (empty($_SESSION['uid']) ||
 147             ($GLOBALS['disablesessionprotection']==false && $_SESSION['ip']!=allIPs()) ||
 148             time() >= $_SESSION['expires_on'])
 149         {
 150             logout();
 151             $userIsLoggedIn = false;
 152             $loginFailure = true;
 153         }
 154         if (!empty($_SESSION['longlastingsession'])) {
 155             $_SESSION['expires_on']=time()+$_SESSION['longlastingsession']; // In case of "Stay signed in" checked.
 156         }
 157         else {
 158             $_SESSION['expires_on']=time()+INACTIVITY_TIMEOUT; // Standard session expiration date.
 159         }
 160         if (!$loginFailure) {
 161             $userIsLoggedIn = true;
 162         }
 163
 164         return $userIsLoggedIn;
 165 }
 166 //==================================================================================================
 167 $userIsLoggedIn = setup_login_state();
 168 //==================================================================================================
 169 //==================================================================================================
 170
 171 // Check PHP version
 172 function checkphpversion()
 173 {
 174     if (version_compare(PHP_VERSION, '5.1.0') < 0)
 175     {
 176         header('Content-Type: text/plain; charset=utf-8');
 177         echo 'Your PHP version is obsolete! Shaarli requires at least php 5.1.0, and thus cannot run. Sorry. Your PHP version has known security vulnerabilities and should be updated as soon as possible.';
 178         exit;
 179     }
 180 }
 181
 182 // Checks if an update is available for Shaarli.
 183 // (at most once a day, and only for registered user.)
 184 // Output: '' = no new version.
 185 //         other= the available version.
 186 function checkUpdate()
 187 {
 188     if (!isLoggedIn()) return ''; // Do not check versions for visitors.
 189     if (empty($GLOBALS['config']['ENABLE_UPDATECHECK'])) return ''; // Do not check if the user doesn't want to.
 190
 191     // Get latest version number at most once a day.
 192     if (!is_file($GLOBALS['config']['UPDATECHECK_FILENAME']) || (filemtime($GLOBALS['config']['UPDATECHECK_FILENAME'])<time()-($GLOBALS['config']['UPDATECHECK_INTERVAL'])))
 193     {
 194         $version=shaarli_version;
 195         list($httpstatus,$headers,$data) = getHTTP('https://raw.githubusercontent.com/shaarli/Shaarli/master/shaarli_version.php',2);
 196         if (strpos($httpstatus,'200 OK')!==false) $version=str_replace(' */ ?>','',str_replace('<?php /* ','',$data));
 197         // If failed, never mind. We don't want to bother the user with that.
 198         file_put_contents($GLOBALS['config']['UPDATECHECK_FILENAME'],$version); // touch file date
 199     }
 200     // Compare versions:
 201     $newestversion=file_get_contents($GLOBALS['config']['UPDATECHECK_FILENAME']);
 202     if (version_compare($newestversion,shaarli_version)==1) return $newestversion;
 203     return '';
 204 }
 205
 206
 207 // -----------------------------------------------------------------------------------------------
 208 // Simple cache system (mainly for the RSS/ATOM feeds).
 209
 210 class pageCache
 211 {
 212     private $url; // Full URL of the page to cache (typically the value returned by pageUrl())
 213     private $shouldBeCached; // boolean: Should this url be cached?
 214     private $filename; // Name of the cache file for this url.
 215
 216     /*
 217          $url = URL (typically the value returned by pageUrl())
 218          $shouldBeCached = boolean. If false, the cache will be disabled.
 219     */
 220     public function __construct($url,$shouldBeCached)
 221     {
 222         $this->url = $url;
 223         $this->filename = $GLOBALS['config']['PAGECACHE'].'/'.sha1($url).'.cache';
 224         $this->shouldBeCached = $shouldBeCached;
 225     }
 226
 227     // If the page should be cached and a cached version exists,
 228     // returns the cached version (otherwise, return null).
 229     public function cachedVersion()
 230     {
 231         if (!$this->shouldBeCached) return null;
 232         if (is_file($this->filename)) { return file_get_contents($this->filename); exit; }
 233         return null;
 234     }
 235
 236     // Put a page in the cache.
 237     public function cache($page)
 238     {
 239         if (!$this->shouldBeCached) return;
 240         file_put_contents($this->filename,$page);
 241     }
 242
 243     // Purge the whole cache.
 244     // (call with pageCache::purgeCache())
 245     public static function purgeCache()
 246     {
 247         if (is_dir($GLOBALS['config']['PAGECACHE']))
 248         {
 249             $handler = opendir($GLOBALS['config']['PAGECACHE']);
 250             if ($handler!==false)
 251             {
 252                 while (($filename = readdir($handler))!==false)
 253                 {
 254                     if (endsWith($filename,'.cache')) { unlink($GLOBALS['config']['PAGECACHE'].'/'.$filename); }
 255                 }
 256                 closedir($handler);
 257             }
 258         }
 259     }
 260
 261 }
 262
 263
 264 // -----------------------------------------------------------------------------------------------
 265 // Log to text file
 266 function logm($message)
 267 {
 268     $t = strval(date('Y/m/d_H:i:s')).' - '.$_SERVER["REMOTE_ADDR"].' - '.strval($message)."\n";
 269     file_put_contents($GLOBALS['config']['DATADIR'].'/log.txt',$t,FILE_APPEND);
 270 }
 271
 272 // Same as nl2br(), but escapes < and >
 273 function nl2br_escaped($html)
 274 {
 275     return str_replace('>','&gt;',str_replace('<','&lt;',nl2br($html)));
 276 }
 277
 278 function escape($str) {
 279     return htmlspecialchars($str, ENT_COMPAT, 'UTF-8', false);
 280 }
 281
 282 function sanitizeLink(&$link) {
 283     $link['url'] = escape($link['url']); // useful?
 284     $link['title'] = escape($link['title']);
 285     $link['description'] = escape($link['description']);
 286     $link['tags'] = escape($link['tags']);
 287 }
 288
 289 // In a string, converts URLs to clickable links.
 290 // Function inspired from http://www.php.net/manual/en/function.preg-replace.php#85722
 291 function text2clickable($url)
 292 {
 293     $redir = empty($GLOBALS['redirector']) ? '' : $GLOBALS['redirector'];
 294     return preg_replace('!(((?:https?|ftp|file)://|apt:|magnet:)\S+[[:alnum:]]/?)!si','<a href="'.$redir.'$1" rel="nofollow">$1</a>',$url);
 295 }
 296
 297 // This function inserts &nbsp; where relevant so that multiple spaces are properly displayed in HTML
 298 // even in the absence of <pre>  (This is used in description to keep text formatting)
 299 function keepMultipleSpaces($text)
 300 {
 301     return str_replace('  ',' &nbsp;',$text);
 302
 303 }
 304 // ------------------------------------------------------------------------------------------
 305 // Sniff browser language to display dates in the right format automatically.
 306 // (Note that is may not work on your server if the corresponding local is not installed.)
 307 function autoLocale()
 308 {
 309     $attempts = array('en_US'); // Default if browser does not send HTTP_ACCEPT_LANGUAGE
 310     if (isset($_SERVER['HTTP_ACCEPT_LANGUAGE'])) // e.g. "fr,fr-fr;q=0.8,en;q=0.5,en-us;q=0.3"
 311     {   // (It's a bit crude, but it works very well. Preferred language is always presented first.)
 312         if (preg_match('/([a-z]{2})-?([a-z]{2})?/i',$_SERVER['HTTP_ACCEPT_LANGUAGE'],$matches)) {
 313             $loc = $matches[1] . (!empty($matches[2]) ? '_' . strtoupper($matches[2]) : '');
 314             $attempts = array($loc.'.UTF-8', $loc, str_replace('_', '-', $loc).'.UTF-8', str_replace('_', '-', $loc),
 315                 $loc . '_' . strtoupper($loc).'.UTF-8', $loc . '_' . strtoupper($loc),
 316                 $loc . '_' . $loc.'.UTF-8', $loc . '_' . $loc, $loc . '-' . strtoupper($loc).'.UTF-8',
 317                 $loc . '-' . strtoupper($loc), $loc . '-' . $loc.'.UTF-8', $loc . '-' . $loc);
 318         }
 319     }
 320     setlocale(LC_TIME, $attempts);  // LC_TIME = Set local for date/time format only.
 321 }
 322
 323 // ------------------------------------------------------------------------------------------
 324 // PubSubHubbub protocol support (if enabled)  [UNTESTED]
 325 // (Source: http://aldarone.fr/les-flux-rss-shaarli-et-pubsubhubbub/ )
 326 if (!empty($GLOBALS['config']['PUBSUBHUB_URL'])) include './publisher.php';
 327 function pubsubhub()
 328 {
 329     if (!empty($GLOBALS['config']['PUBSUBHUB_URL']))
 330     {
 331        $p = new Publisher($GLOBALS['config']['PUBSUBHUB_URL']);
 332        $topic_url = array (
 333                        indexUrl().'?do=atom',
 334                        indexUrl().'?do=rss'
 335                     );
 336        $p->publish_update($topic_url);
 337     }
 338 }
 339
 340 // ------------------------------------------------------------------------------------------
 341 // Session management
 342
 343 // Returns the IP address of the client (Used to prevent session cookie hijacking.)
 344 function allIPs()
 345 {
 346     $ip = $_SERVER["REMOTE_ADDR"];
 347     // Then we use more HTTP headers to prevent session hijacking from users behind the same proxy.
 348     if (isset($_SERVER['HTTP_X_FORWARDED_FOR'])) { $ip=$ip.'_'.$_SERVER['HTTP_X_FORWARDED_FOR']; }
 349     if (isset($_SERVER['HTTP_CLIENT_IP'])) { $ip=$ip.'_'.$_SERVER['HTTP_CLIENT_IP']; }
 350     return $ip;
 351 }
 352
 353 function fillSessionInfo() {
 354         $_SESSION['uid'] = sha1(uniqid('',true).'_'.mt_rand()); // Generate unique random number (different than phpsessionid)
 355         $_SESSION['ip']=allIPs();                // We store IP address(es) of the client to make sure session is not hijacked.
 356         $_SESSION['username']=$GLOBALS['login'];
 357         $_SESSION['expires_on']=time()+INACTIVITY_TIMEOUT;  // Set session expiration.
 358 }
 359
 360 // Check that user/password is correct.
 361 function check_auth($login,$password)
 362 {
 363     $hash = sha1($password.$login.$GLOBALS['salt']);
 364     if ($login==$GLOBALS['login'] && $hash==$GLOBALS['hash'])
 365     {   // Login/password is correct.
 366                 fillSessionInfo();
 367         logm('Login successful');
 368         return True;
 369     }
 370     logm('Login failed for user '.$login);
 371     return False;
 372 }
 373
 374 // Returns true if the user is logged in.
 375 function isLoggedIn()
 376 {
 377     global $userIsLoggedIn;
 378     return $userIsLoggedIn;
 379 }
 380
 381 // Force logout.
 382 function logout() {
 383     if (isset($_SESSION)) {
 384         unset($_SESSION['uid']);
 385         unset($_SESSION['ip']);
 386         unset($_SESSION['username']);
 387         unset($_SESSION['privateonly']);
 388     }
 389     setcookie('shaarli_staySignedIn', FALSE, 0, WEB_PATH);
 390 }
 391
 392
 393 // ------------------------------------------------------------------------------------------
 394 // Brute force protection system
 395 // Several consecutive failed logins will ban the IP address for 30 minutes.
 396 if (!is_file($GLOBALS['config']['IPBANS_FILENAME'])) file_put_contents($GLOBALS['config']['IPBANS_FILENAME'], "<?php\n\$GLOBALS['IPBANS']=".var_export(array('FAILURES'=>array(),'BANS'=>array()),true).";\n?>");
 397 include $GLOBALS['config']['IPBANS_FILENAME'];
 398 // Signal a failed login. Will ban the IP if too many failures:
 399 function ban_loginFailed()
 400 {
 401     $ip=$_SERVER["REMOTE_ADDR"]; $gb=$GLOBALS['IPBANS'];
 402     if (!isset($gb['FAILURES'][$ip])) $gb['FAILURES'][$ip]=0;
 403     $gb['FAILURES'][$ip]++;
 404     if ($gb['FAILURES'][$ip]>($GLOBALS['config']['BAN_AFTER']-1))
 405     {
 406         $gb['BANS'][$ip]=time()+$GLOBALS['config']['BAN_DURATION'];
 407         logm('IP address banned from login');
 408     }
 409     $GLOBALS['IPBANS'] = $gb;
 410     file_put_contents($GLOBALS['config']['IPBANS_FILENAME'], "<?php\n\$GLOBALS['IPBANS']=".var_export($gb,true).";\n?>");
 411 }
 412
 413 // Signals a successful login. Resets failed login counter.
 414 function ban_loginOk()
 415 {
 416     $ip=$_SERVER["REMOTE_ADDR"]; $gb=$GLOBALS['IPBANS'];
 417     unset($gb['FAILURES'][$ip]); unset($gb['BANS'][$ip]);
 418     $GLOBALS['IPBANS'] = $gb;
 419     file_put_contents($GLOBALS['config']['IPBANS_FILENAME'], "<?php\n\$GLOBALS['IPBANS']=".var_export($gb,true).";\n?>");
 420 }
 421
 422 // Checks if the user CAN login. If 'true', the user can try to login.
 423 function ban_canLogin()
 424 {
 425     $ip=$_SERVER["REMOTE_ADDR"]; $gb=$GLOBALS['IPBANS'];
 426     if (isset($gb['BANS'][$ip]))
 427     {
 428         // User is banned. Check if the ban has expired:
 429         if ($gb['BANS'][$ip]<=time())
 430         {   // Ban expired, user can try to login again.
 431             logm('Ban lifted.');
 432             unset($gb['FAILURES'][$ip]); unset($gb['BANS'][$ip]);
 433             file_put_contents($GLOBALS['config']['IPBANS_FILENAME'], "<?php\n\$GLOBALS['IPBANS']=".var_export($gb,true).";\n?>");
 434             return true; // Ban has expired, user can login.
 435         }
 436         return false; // User is banned.
 437     }
 438     return true; // User is not banned.
 439 }
 440
 441 // ------------------------------------------------------------------------------------------
 442 // Process login form: Check if login/password is correct.
 443 if (isset($_POST['login']))
 444 {
 445     if (!ban_canLogin()) die('I said: NO. You are banned for the moment. Go away.');
 446     if (isset($_POST['password']) && tokenOk($_POST['token']) && (check_auth($_POST['login'], $_POST['password'])))
 447     {   // Login/password is OK.
 448         ban_loginOk();
 449         // If user wants to keep the session cookie even after the browser closes:
 450         if (!empty($_POST['longlastingsession']))
 451         {
 452                         setcookie('shaarli_staySignedIn', STAY_SIGNED_IN_TOKEN, time()+31536000, WEB_PATH);
 453             $_SESSION['longlastingsession']=31536000;  // (31536000 seconds = 1 year)
 454             $_SESSION['expires_on']=time()+$_SESSION['longlastingsession'];  // Set session expiration on server-side.
 455
 456             $cookiedir = ''; if(dirname($_SERVER['SCRIPT_NAME'])!='/') $cookiedir=dirname($_SERVER["SCRIPT_NAME"]).'/';
 457             session_set_cookie_params($_SESSION['longlastingsession'],$cookiedir,$_SERVER['SERVER_NAME']); // Set session cookie expiration on client side
 458             // Note: Never forget the trailing slash on the cookie path!
 459             session_regenerate_id(true);  // Send cookie with new expiration date to browser.
 460         }
 461         else // Standard session expiration (=when browser closes)
 462         {
 463             $cookiedir = ''; if(dirname($_SERVER['SCRIPT_NAME'])!='/') $cookiedir=dirname($_SERVER["SCRIPT_NAME"]).'/';
 464             session_set_cookie_params(0,$cookiedir,$_SERVER['SERVER_NAME']); // 0 means "When browser closes"
 465             session_regenerate_id(true);
 466         }
 467         // Optional redirect after login:
 468         if (isset($_GET['post'])) { header('Location: ?post='.urlencode($_GET['post']).(!empty($_GET['title'])?'&title='.urlencode($_GET['title']):'').(!empty($_GET['description'])?'&description='.urlencode($_GET['description']):'').(!empty($_GET['source'])?'&source='.urlencode($_GET['source']):'')); exit; }
 469         if (isset($_POST['returnurl']))
 470         {
 471             if (endsWith($_POST['returnurl'],'?do=login')) { header('Location: ?'); exit; } // Prevent loops over login screen.
 472             header('Location: '.$_POST['returnurl']); exit;
 473         }
 474         header('Location: ?'); exit;
 475     }
 476     else
 477     {
 478         ban_loginFailed();
 479         $redir = '';
 480         if (isset($_GET['post'])) { $redir = '&post='.urlencode($_GET['post']).(!empty($_GET['title'])?'&title='.urlencode($_GET['title']):'').(!empty($_GET['description'])?'&description='.urlencode($_GET['description']):'').(!empty($_GET['source'])?'&source='.urlencode($_GET['source']):''); }
 481         echo '<script>alert("Wrong login/password.");document.location=\'?do=login'.$redir.'\';</script>'; // Redirect to login screen.
 482         exit;
 483     }
 484 }
 485
 486 // ------------------------------------------------------------------------------------------
 487 // Misc utility functions:
 488
 489 // Returns the server URL (including port and http/https), without path.
 490 // e.g. "http://myserver.com:8080"
 491 // You can append $_SERVER['SCRIPT_NAME'] to get the current script URL.
 492 function serverUrl()
 493 {
 494     $https = (!empty($_SERVER['HTTPS']) && (strtolower($_SERVER['HTTPS'])=='on')) || $_SERVER["SERVER_PORT"]=='443'; // HTTPS detection.
 495     $serverport = ($_SERVER["SERVER_PORT"]=='80' || ($https && $_SERVER["SERVER_PORT"]=='443') ? '' : ':'.$_SERVER["SERVER_PORT"]);
 496     return 'http'.($https?'s':'').'://'.$_SERVER['SERVER_NAME'].$serverport;
 497 }
 498
 499 // Returns the absolute URL of current script, without the query.
 500 // (e.g. http://sebsauvage.net/links/)
 501 function indexUrl()
 502 {
 503     $scriptname = $_SERVER["SCRIPT_NAME"];
 504     // If the script is named 'index.php', we remove it (for better looking URLs,
 505     // e.g. http://mysite.com/shaarli/?abcde instead of http://mysite.com/shaarli/index.php?abcde)
 506     if (endswith($scriptname,'index.php')) $scriptname = substr($scriptname,0,strlen($scriptname)-9);
 507     return serverUrl() . $scriptname;
 508 }
 509
 510 // Returns the absolute URL of current script, WITH the query.
 511 // (e.g. http://sebsauvage.net/links/?toto=titi&spamspamspam=humbug)
 512 function pageUrl()
 513 {
 514     return indexUrl().(!empty($_SERVER["QUERY_STRING"]) ? '?'.$_SERVER["QUERY_STRING"] : '');
 515 }
 516
 517 // Convert post_max_size/upload_max_filesize (e.g. '16M') parameters to bytes.
 518 function return_bytes($val)
 519 {
 520     $val = trim($val); $last=strtolower($val[strlen($val)-1]);
 521     switch($last)
 522     {
 523         case 'g': $val *= 1024;
 524         case 'm': $val *= 1024;
 525         case 'k': $val *= 1024;
 526     }
 527     return $val;
 528 }
 529
 530 // Try to determine max file size for uploads (POST).
 531 // Returns an integer (in bytes)
 532 function getMaxFileSize()
 533 {
 534     $size1 = return_bytes(ini_get('post_max_size'));
 535     $size2 = return_bytes(ini_get('upload_max_filesize'));
 536     // Return the smaller of two:
 537     $maxsize = min($size1,$size2);
 538     // FIXME: Then convert back to readable notations ? (e.g. 2M instead of 2000000)
 539     return $maxsize;
 540 }
 541
 542 /*  Converts a linkdate time (YYYYMMDD_HHMMSS) of an article to a timestamp (Unix epoch)
 543     (used to build the ADD_DATE attribute in Netscape-bookmarks file)
 544     PS: I could have used strptime(), but it does not exist on Windows. I'm too kind. */
 545 function linkdate2timestamp($linkdate)
 546 {
 547     if(strcmp($linkdate, '_000000') !== 0 || !$linkdate){
 548         $Y=$M=$D=$h=$m=$s=0;
 549         $r = sscanf($linkdate,'%4d%2d%2d_%2d%2d%2d',$Y,$M,$D,$h,$m,$s);
 550         return mktime($h,$m,$s,$M,$D,$Y);
 551     }
 552     return time();
 553 }
 554
 555 /*  Converts a linkdate time (YYYYMMDD_HHMMSS) of an article to a RFC822 date.
 556     (used to build the pubDate attribute in RSS feed.)  */
 557 function linkdate2rfc822($linkdate)
 558 {
 559     return date('r',linkdate2timestamp($linkdate)); // 'r' is for RFC822 date format.
 560 }
 561
 562 /*  Converts a linkdate time (YYYYMMDD_HHMMSS) of an article to a ISO 8601 date.
 563     (used to build the updated tags in ATOM feed.)  */
 564 function linkdate2iso8601($linkdate)
 565 {
 566     return date('c',linkdate2timestamp($linkdate)); // 'c' is for ISO 8601 date format.
 567 }
 568
 569 // Parse HTTP response headers and return an associative array.
 570 function http_parse_headers_shaarli( $headers )
 571 {
 572     $res=array();
 573     foreach($headers as $header)
 574     {
 575         $i = strpos($header,': ');
 576         if ($i!==false)
 577         {
 578             $key=substr($header,0,$i);
 579             $value=substr($header,$i+2,strlen($header)-$i-2);
 580             $res[$key]=$value;
 581         }
 582     }
 583     return $res;
 584 }
 585
 586 /* GET an URL.
 587    Input: $url : URL to get (http://...)
 588           $timeout : Network timeout (will wait this many seconds for an anwser before giving up).
 589    Output: An array.  [0] = HTTP status message (e.g. "HTTP/1.1 200 OK") or error message
 590                       [1] = associative array containing HTTP response headers (e.g. echo getHTTP($url)[1]['Content-Type'])
 591                       [2] = data
 592     Example: list($httpstatus,$headers,$data) = getHTTP('http://sebauvage.net/');
 593              if (strpos($httpstatus,'200 OK')!==false)
 594                  echo 'Data type: '.htmlspecialchars($headers['Content-Type']);
 595              else
 596                  echo 'There was an error: '.htmlspecialchars($httpstatus)
 597 */
 598 function getHTTP($url,$timeout=30)
 599 {
 600     try
 601     {
 602         $options = array('http'=>array('method'=>'GET','timeout' => $timeout, 'user_agent' => 'Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:23.0) Gecko/20100101 Firefox/23.0')); // Force network timeout
 603         $context = stream_context_create($options);
 604         $data=file_get_contents($url,false,$context,-1, 4000000); // We download at most 4 Mb from source.
 605         if (!$data) { return array('HTTP Error',array(),''); }
 606         $httpStatus=$http_response_header[0]; // e.g. "HTTP/1.1 200 OK"
 607         $responseHeaders=http_parse_headers_shaarli($http_response_header);
 608         return array($httpStatus,$responseHeaders,$data);
 609     }
 610     catch (Exception $e)  // getHTTP *can* fail silently (we don't care if the title cannot be fetched)
 611     {
 612         return array($e->getMessage(),'','');
 613     }
 614 }
 615
 616 // Extract title from an HTML document.
 617 // (Returns an empty string if not found.)
 618 function html_extract_title($html)
 619 {
 620   return preg_match('!<title>(.*?)</title>!is', $html, $matches) ? trim(str_replace("\n",' ', $matches[1])) : '' ;
 621 }
 622
 623 // ------------------------------------------------------------------------------------------
 624 // Token management for XSRF protection
 625 // Token should be used in any form which acts on data (create,update,delete,import...).
 626 if (!isset($_SESSION['tokens'])) $_SESSION['tokens']=array();  // Token are attached to the session.
 627
 628 // Returns a token.
 629 function getToken()
 630 {
 631     $rnd = sha1(uniqid('',true).'_'.mt_rand().$GLOBALS['salt']);  // We generate a random string.
 632     $_SESSION['tokens'][$rnd]=1;  // Store it on the server side.
 633     return $rnd;
 634 }
 635
 636 // Tells if a token is OK. Using this function will destroy the token.
 637 // true=token is OK.
 638 function tokenOk($token)
 639 {
 640     if (isset($_SESSION['tokens'][$token]))
 641     {
 642         unset($_SESSION['tokens'][$token]); // Token is used: destroy it.
 643         return true; // Token is OK.
 644     }
 645     return false; // Wrong token, or already used.
 646 }
 647
 648 // ------------------------------------------------------------------------------------------
 649 /* This class is in charge of building the final page.
 650    (This is basically a wrapper around RainTPL which pre-fills some fields.)
 651    p = new pageBuilder;
 652    p.assign('myfield','myvalue');
 653    p.renderPage('mytemplate');
 654
 655 */
 656 class pageBuilder
 657 {
 658     private $tpl; // RainTPL template
 659
 660     function __construct()
 661     {
 662         $this->tpl=false;
 663     }
 664
 665     private function initialize()
 666     {
 667         $this->tpl = new RainTPL;
 668         $this->tpl->assign('newversion',escape(checkUpdate()));
 669         $this->tpl->assign('feedurl',escape(indexUrl()));
 670         $searchcrits=''; // Search criteria
 671         if (!empty($_GET['searchtags'])) $searchcrits.='&searchtags='.urlencode($_GET['searchtags']);
 672         elseif (!empty($_GET['searchterm'])) $searchcrits.='&searchterm='.urlencode($_GET['searchterm']);
 673         $this->tpl->assign('searchcrits',$searchcrits);
 674         $this->tpl->assign('source',indexUrl());
 675         $this->tpl->assign('version',shaarli_version);
 676         $this->tpl->assign('scripturl',indexUrl());
 677         $this->tpl->assign('pagetitle','Shaarli');
 678         $this->tpl->assign('privateonly',!empty($_SESSION['privateonly'])); // Show only private links?
 679         if (!empty($GLOBALS['title'])) $this->tpl->assign('pagetitle',$GLOBALS['title']);
 680         if (!empty($GLOBALS['titleLink'])) $this->tpl->assign('titleLink',$GLOBALS['titleLink']);
 681         if (!empty($GLOBALS['pagetitle'])) $this->tpl->assign('pagetitle',$GLOBALS['pagetitle']);
 682         $this->tpl->assign('shaarlititle',empty($GLOBALS['title']) ? 'Shaarli': $GLOBALS['title'] );
 683         return;
 684     }
 685
 686     // The following assign() method is basically the same as RainTPL (except that it's lazy)
 687     public function assign($what,$where)
 688     {
 689         if ($this->tpl===false) $this->initialize(); // Lazy initialization
 690         $this->tpl->assign($what,$where);
 691     }
 692
 693     // Render a specific page (using a template).
 694     // e.g. pb.renderPage('picwall')
 695     public function renderPage($page)
 696     {
 697         if ($this->tpl===false) $this->initialize(); // Lazy initialization
 698         $this->tpl->draw($page);
 699     }
 700 }
 701
 702 // ------------------------------------------------------------------------------------------
 703 // Output the last N links in RSS 2.0 format.
 704 function showRSS()
 705 {
 706     header('Content-Type: application/rss+xml; charset=utf-8');
 707
 708     // $usepermalink : If true, use permalink instead of final link.
 709     // User just has to add 'permalink' in URL parameters. e.g. http://mysite.com/shaarli/?do=rss&permalinks
 710     // Also enabled through a config option
 711     $usepermalinks = isset($_GET['permalinks']) || !$GLOBALS['config']['ENABLE_RSS_PERMALINKS'];
 712
 713     // Cache system
 714     $query = $_SERVER["QUERY_STRING"];
 715     $cache = new pageCache(pageUrl(),startsWith($query,'do=rss') && !isLoggedIn());
 716     $cached = $cache->cachedVersion(); if (!empty($cached)) { echo $cached; exit; }
 717
 718     // If cached was not found (or not usable), then read the database and build the response:
 719     $LINKSDB = new LinkDB(
 720         isLoggedIn() || $GLOBALS['config']['OPEN_SHAARLI'],
 721         $GLOBALS['config']['HIDE_PUBLIC_LINKS']
 722     );
 723     // Read links from database (and filter private links if user it not logged in).
 724
 725     // Optionally filter the results:
 726     $linksToDisplay=array();
 727     if (!empty($_GET['searchterm'])) $linksToDisplay = $LINKSDB->filterFulltext($_GET['searchterm']);
 728     else if (!empty($_GET['searchtags']))   $linksToDisplay = $LINKSDB->filterTags(trim($_GET['searchtags']));
 729     else $linksToDisplay = $LINKSDB;
 730
 731     $nblinksToDisplay = 50;  // Number of links to display.
 732     if (!empty($_GET['nb']))  // In URL, you can specificy the number of links. Example: nb=200 or nb=all for all links.
 733     {
 734         $nblinksToDisplay = $_GET['nb']=='all' ? count($linksToDisplay) : max($_GET['nb']+0,1) ;
 735     }
 736
 737     $pageaddr=escape(indexUrl());
 738     echo '<?xml version="1.0" encoding="UTF-8"?><rss version="2.0" xmlns:content="http://purl.org/rss/1.0/modules/content/">';
 739     echo '<channel><title>'.$GLOBALS['title'].'</title><link>'.$pageaddr.'</link>';
 740     echo '<description>Shared links</description><language>en-en</language><copyright>'.$pageaddr.'</copyright>'."\n\n";
 741     if (!empty($GLOBALS['config']['PUBSUBHUB_URL']))
 742     {
 743         echo '<!-- PubSubHubbub Discovery -->';
 744         echo '<link rel="hub" href="'.escape($GLOBALS['config']['PUBSUBHUB_URL']).'" xmlns="http://www.w3.org/2005/Atom" />';
 745         echo '<link rel="self" href="'.$pageaddr.'?do=rss" xmlns="http://www.w3.org/2005/Atom" />';
 746         echo '<!-- End Of PubSubHubbub Discovery -->';
 747     }
 748     $i=0;
 749     $keys=array(); foreach($linksToDisplay as $key=>$value) { $keys[]=$key; }  // No, I can't use array_keys().
 750     while ($i<$nblinksToDisplay && $i<count($keys))
 751     {
 752         $link = $linksToDisplay[$keys[$i]];
 753         $guid = $pageaddr.'?'.smallHash($link['linkdate']);
 754         $rfc822date = linkdate2rfc822($link['linkdate']);
 755         $absurl = $link['url'];
 756         if (startsWith($absurl,'?')) $absurl=$pageaddr.$absurl;  // make permalink URL absolute
 757         if ($usepermalinks===true)
 758             echo '<item><title>'.$link['title'].'</title><guid isPermaLink="true">'.$guid.'</guid><link>'.$guid.'</link>';
 759         else
 760             echo '<item><title>'.$link['title'].'</title><guid isPermaLink="false">'.$guid.'</guid><link>'.$absurl.'</link>';
 761         if (!$GLOBALS['config']['HIDE_TIMESTAMPS'] || isLoggedIn()) echo '<pubDate>'.escape($rfc822date)."</pubDate>\n";
 762         if ($link['tags']!='') // Adding tags to each RSS entry (as mentioned in RSS specification)
 763         {
 764             foreach(explode(' ',$link['tags']) as $tag) { echo '<category domain="'.$pageaddr.'">'.$tag.'</category>'."\n"; }
 765         }
 766
 767         // Add permalink in description
 768         $descriptionlink = '(<a href="'.$guid.'">Permalink</a>)';
 769         // If user wants permalinks first, put the final link in description
 770         if ($usepermalinks===true) $descriptionlink = '(<a href="'.$absurl.'">Link</a>)';
 771         if (strlen($link['description'])>0) $descriptionlink = '<br>'.$descriptionlink;
 772         echo '<description><![CDATA['.nl2br(keepMultipleSpaces(text2clickable($link['description']))).$descriptionlink.']]></description>'."\n</item>\n";
 773         $i++;
 774     }
 775     echo '</channel></rss><!-- Cached version of '.escape(pageUrl()).' -->';
 776
 777     $cache->cache(ob_get_contents());
 778     ob_end_flush();
 779     exit;
 780 }
 781
 782 // ------------------------------------------------------------------------------------------
 783 // Output the last N links in ATOM format.
 784 function showATOM()
 785 {
 786     header('Content-Type: application/atom+xml; charset=utf-8');
 787
 788     // $usepermalink : If true, use permalink instead of final link.
 789     // User just has to add 'permalink' in URL parameters. e.g. http://mysite.com/shaarli/?do=atom&permalinks
 790     $usepermalinks = isset($_GET['permalinks']) || !$GLOBALS['config']['ENABLE_RSS_PERMALINKS'];
 791
 792     // Cache system
 793     $query = $_SERVER["QUERY_STRING"];
 794     $cache = new pageCache(pageUrl(),startsWith($query,'do=atom') && !isLoggedIn());
 795     $cached = $cache->cachedVersion(); if (!empty($cached)) { echo $cached; exit; }
 796     // If cached was not found (or not usable), then read the database and build the response:
 797
 798 // Read links from database (and filter private links if used it not logged in).
 799     $LINKSDB = new LinkDB(
 800         isLoggedIn() || $GLOBALS['config']['OPEN_SHAARLI'],
 801         $GLOBALS['config']['HIDE_PUBLIC_LINKS']
 802     );
 803
 804     // Optionally filter the results:
 805     $linksToDisplay=array();
 806     if (!empty($_GET['searchterm'])) $linksToDisplay = $LINKSDB->filterFulltext($_GET['searchterm']);
 807     else if (!empty($_GET['searchtags']))   $linksToDisplay = $LINKSDB->filterTags(trim($_GET['searchtags']));
 808     else $linksToDisplay = $LINKSDB;
 809
 810     $nblinksToDisplay = 50;  // Number of links to display.
 811     if (!empty($_GET['nb']))  // In URL, you can specificy the number of links. Example: nb=200 or nb=all for all links.
 812     {
 813         $nblinksToDisplay = $_GET['nb']=='all' ? count($linksToDisplay) : max($_GET['nb']+0,1) ;
 814     }
 815
 816     $pageaddr=escape(indexUrl());
 817     $latestDate = '';
 818     $entries='';
 819     $i=0;
 820     $keys=array(); foreach($linksToDisplay as $key=>$value) { $keys[]=$key; }  // No, I can't use array_keys().
 821     while ($i<$nblinksToDisplay && $i<count($keys))
 822     {
 823         $link = $linksToDisplay[$keys[$i]];
 824         $guid = $pageaddr.'?'.smallHash($link['linkdate']);
 825         $iso8601date = linkdate2iso8601($link['linkdate']);
 826         $latestDate = max($latestDate,$iso8601date);
 827         $absurl = $link['url'];
 828         if (startsWith($absurl,'?')) $absurl=$pageaddr.$absurl;  // make permalink URL absolute
 829         $entries.='<entry><title>'.$link['title'].'</title>';
 830         if ($usepermalinks===true)
 831             $entries.='<link href="'.$guid.'" /><id>'.$guid.'</id>';
 832         else
 833             $entries.='<link href="'.$absurl.'" /><id>'.$guid.'</id>';
 834         if (!$GLOBALS['config']['HIDE_TIMESTAMPS'] || isLoggedIn()) $entries.='<updated>'.escape($iso8601date).'</updated>';
 835
 836         // Add permalink in description
 837         $descriptionlink = '(<a href="'.$guid.'">Permalink</a>)';
 838         // If user wants permalinks first, put the final link in description
 839         if ($usepermalinks===true) $descriptionlink = '(<a href="'.$absurl.'">Link</a>)';
 840         if (strlen($link['description'])>0) $descriptionlink = '<br>'.$descriptionlink;
 841
 842         $entries.='<content type="html"><![CDATA['.nl2br(keepMultipleSpaces(text2clickable($link['description']))).$descriptionlink."]]></content>\n";
 843         if ($link['tags']!='') // Adding tags to each ATOM entry (as mentioned in ATOM specification)
 844         {
 845             foreach(explode(' ',$link['tags']) as $tag)
 846                 { $entries.='<category scheme="'.$pageaddr.'" term="'.$tag.'" />'."\n"; }
 847         }
 848         $entries.="</entry>\n";
 849         $i++;
 850     }
 851     $feed='<?xml version="1.0" encoding="UTF-8"?><feed xmlns="http://www.w3.org/2005/Atom">';
 852     $feed.='<title>'.$GLOBALS['title'].'</title>';
 853     if (!$GLOBALS['config']['HIDE_TIMESTAMPS'] || isLoggedIn()) $feed.='<updated>'.escape($latestDate).'</updated>';
 854     $feed.='<link rel="self" href="'.escape(serverUrl().$_SERVER["REQUEST_URI"]).'" />';
 855     if (!empty($GLOBALS['config']['PUBSUBHUB_URL']))
 856     {
 857         $feed.='<!-- PubSubHubbub Discovery -->';
 858         $feed.='<link rel="hub" href="'.escape($GLOBALS['config']['PUBSUBHUB_URL']).'" />';
 859         $feed.='<!-- End Of PubSubHubbub Discovery -->';
 860     }
 861     $feed.='<author><name>'.$pageaddr.'</name><uri>'.$pageaddr.'</uri></author>';
 862     $feed.='<id>'.$pageaddr.'</id>'."\n\n"; // Yes, I know I should use a real IRI (RFC3987), but the site URL will do.
 863     $feed.=$entries;
 864     $feed.='</feed><!-- Cached version of '.escape(pageUrl()).' -->';
 865     echo $feed;
 866
 867     $cache->cache(ob_get_contents());
 868     ob_end_flush();
 869     exit;
 870 }
 871
 872 // ------------------------------------------------------------------------------------------
 873 // Daily RSS feed: 1 RSS entry per day giving all the links on that day.
 874 // Gives the last 7 days (which have links).
 875 // This RSS feed cannot be filtered.
 876 function showDailyRSS()
 877 {
 878     // Cache system
 879     $query = $_SERVER["QUERY_STRING"];
 880     $cache = new pageCache(pageUrl(),startsWith($query,'do=dailyrss') && !isLoggedIn());
 881     $cached = $cache->cachedVersion(); if (!empty($cached)) { echo $cached; exit; }
 882     // If cached was not found (or not usable), then read the database and build the response:
 883
 884 // Read links from database (and filter private links if used it not logged in).
 885     $LINKSDB = new LinkDB(
 886         isLoggedIn() || $GLOBALS['config']['OPEN_SHAARLI'],
 887         $GLOBALS['config']['HIDE_PUBLIC_LINKS']
 888     );
 889
 890     /* Some Shaarlies may have very few links, so we need to look
 891        back in time (rsort()) until we have enough days ($nb_of_days).
 892     */
 893     $linkdates=array(); foreach($LINKSDB as $linkdate=>$value) { $linkdates[]=$linkdate; }
 894     rsort($linkdates);
 895     $nb_of_days=7; // We take 7 days.
 896     $today=Date('Ymd');
 897     $days=array();
 898     foreach($linkdates as $linkdate)
 899     {
 900         $day=substr($linkdate,0,8); // Extract day (without time)
 901         if (strcmp($day,$today)<0)
 902         {
 903             if (empty($days[$day])) $days[$day]=array();
 904             $days[$day][]=$linkdate;
 905         }
 906         if (count($days)>$nb_of_days) break; // Have we collected enough days?
 907     }
 908
 909     // Build the RSS feed.
 910     header('Content-Type: application/rss+xml; charset=utf-8');
 911     $pageaddr=escape(indexUrl());
 912     echo '<?xml version="1.0" encoding="UTF-8"?><rss version="2.0">';
 913     echo '<channel><title>Daily - '.$GLOBALS['title'].'</title><link>'.$pageaddr.'</link>';
 914     echo '<description>Daily shared links</description><language>en-en</language><copyright>'.$pageaddr.'</copyright>'."\n";
 915
 916     foreach($days as $day=>$linkdates) // For each day.
 917     {
 918         $daydate = utf8_encode(strftime('%A %d, %B %Y',linkdate2timestamp($day.'_000000'))); // Full text date
 919         $rfc822date = linkdate2rfc822($day.'_000000');
 920         $absurl=escape(indexUrl().'?do=daily&day='.$day);  // Absolute URL of the corresponding "Daily" page.
 921         echo '<item><title>'.$GLOBALS['title'].' - '.$daydate.'</title><guid>'.$absurl.'</guid><link>'.$absurl.'</link>';
 922         echo '<pubDate>'.escape($rfc822date)."</pubDate>";
 923
 924         // Build the HTML body of this RSS entry.
 925         $html='';
 926         $href='';
 927         $links=array();
 928         // We pre-format some fields for proper output.
 929         foreach($linkdates as $linkdate)
 930         {
 931             $l = $LINKSDB[$linkdate];
 932             $l['formatedDescription']=nl2br(keepMultipleSpaces(text2clickable($l['description'])));
 933             $l['thumbnail'] = thumbnail($l['url']);
 934             $l['timestamp'] = linkdate2timestamp($l['linkdate']);
 935             if (startsWith($l['url'],'?')) $l['url']=indexUrl().$l['url'];  // make permalink URL absolute
 936             $links[$linkdate]=$l;
 937         }
 938         // Then build the HTML for this day:
 939         $tpl = new RainTPL;
 940         $tpl->assign('links',$links);
 941         $html = $tpl->draw('dailyrss',$return_string=true);
 942         echo "\n";
 943         echo '<description><![CDATA['.$html.']]></description>'."\n</item>\n\n";
 944
 945     }
 946     echo '</channel></rss><!-- Cached version of '.escape(pageUrl()).' -->';
 947
 948     $cache->cache(ob_get_contents());
 949     ob_end_flush();
 950     exit;
 951 }
 952
 953 // "Daily" page.
 954 function showDaily()
 955 {
 956     $LINKSDB = new LinkDB(
 957         isLoggedIn() || $GLOBALS['config']['OPEN_SHAARLI'],
 958         $GLOBALS['config']['HIDE_PUBLIC_LINKS']
 959     );
 960
 961     $day=Date('Ymd',strtotime('-1 day')); // Yesterday, in format YYYYMMDD.
 962     if (isset($_GET['day'])) $day=$_GET['day'];
 963
 964     $days = $LINKSDB->days();
 965     $i = array_search($day,$days);
 966     if ($i==false) { $i=count($days)-1; $day=$days[$i]; }
 967     $previousday='';
 968     $nextday='';
 969     if ($i!==false)
 970     {
 971         if ($i>1) $previousday=$days[$i-1];
 972         if ($i<count($days)-1) $nextday=$days[$i+1];
 973     }
 974
 975     $linksToDisplay=$LINKSDB->filterDay($day);
 976     // We pre-format some fields for proper output.
 977     foreach($linksToDisplay as $key=>$link)
 978     {
 979
 980         $taglist = explode(' ',$link['tags']);
 981         uasort($taglist, 'strcasecmp');
 982         $linksToDisplay[$key]['taglist']=$taglist;
 983         $linksToDisplay[$key]['formatedDescription']=nl2br(keepMultipleSpaces(text2clickable($link['description'])));
 984         $linksToDisplay[$key]['thumbnail'] = thumbnail($link['url']);
 985         $linksToDisplay[$key]['timestamp'] = linkdate2timestamp($link['linkdate']);
 986     }
 987
 988     /* We need to spread the articles on 3 columns.
 989        I did not want to use a JavaScript lib like http://masonry.desandro.com/
 990        so I manually spread entries with a simple method: I roughly evaluate the
 991        height of a div according to title and description length.
 992     */
 993     $columns=array(array(),array(),array()); // Entries to display, for each column.
 994     $fill=array(0,0,0);  // Rough estimate of columns fill.
 995     foreach($linksToDisplay as $key=>$link)
 996     {
 997         // Roughly estimate length of entry (by counting characters)
 998         // Title: 30 chars = 1 line. 1 line is 30 pixels height.
 999         // Description: 836 characters gives roughly 342 pixel height.
1000         // This is not perfect, but it's usually OK.
1001         $length=strlen($link['title'])+(342*strlen($link['description']))/836;
1002         if ($link['thumbnail']) $length +=100; // 1 thumbnails roughly takes 100 pixels height.
1003         // Then put in column which is the less filled:
1004         $smallest=min($fill); // find smallest value in array.
1005         $index=array_search($smallest,$fill); // find index of this smallest value.
1006         array_push($columns[$index],$link); // Put entry in this column.
1007         $fill[$index]+=$length;
1008     }
1009     $PAGE = new pageBuilder;
1010     $PAGE->assign('linksToDisplay',$linksToDisplay);
1011     $PAGE->assign('linkcount',count($LINKSDB));
1012     $PAGE->assign('cols', $columns);
1013     $PAGE->assign('day',linkdate2timestamp($day.'_000000'));
1014     $PAGE->assign('previousday',$previousday);
1015     $PAGE->assign('nextday',$nextday);
1016     $PAGE->renderPage('daily');
1017     exit;
1018 }
1019
1020
1021 // ------------------------------------------------------------------------------------------
1022 // Render HTML page (according to URL parameters and user rights)
1023 function renderPage()
1024 {
1025     $LINKSDB = new LinkDB(
1026         isLoggedIn() || $GLOBALS['config']['OPEN_SHAARLI'],
1027         $GLOBALS['config']['HIDE_PUBLIC_LINKS']
1028     );
1029
1030     // -------- Display login form.
1031     if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=login'))
1032     {
1033         if ($GLOBALS['config']['OPEN_SHAARLI']) { header('Location: ?'); exit; }  // No need to login for open Shaarli
1034         $token=''; if (ban_canLogin()) $token=getToken(); // Do not waste token generation if not useful.
1035         $PAGE = new pageBuilder;
1036         $PAGE->assign('token',$token);
1037         $PAGE->assign('returnurl',(isset($_SERVER['HTTP_REFERER']) ? escape($_SERVER['HTTP_REFERER']):''));
1038         $PAGE->renderPage('loginform');
1039         exit;
1040     }
1041     // -------- User wants to logout.
1042     if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=logout'))
1043     {
1044         invalidateCaches();
1045         logout();
1046         header('Location: ?');
1047         exit;
1048     }
1049
1050     // -------- Picture wall
1051     if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=picwall'))
1052     {
1053         // Optionally filter the results:
1054         $links=array();
1055         if (!empty($_GET['searchterm'])) $links = $LINKSDB->filterFulltext($_GET['searchterm']);
1056         elseif (!empty($_GET['searchtags']))   $links = $LINKSDB->filterTags(trim($_GET['searchtags']));
1057         else $links = $LINKSDB;
1058
1059         $body='';
1060         $linksToDisplay=array();
1061
1062         // Get only links which have a thumbnail.
1063         foreach($links as $link)
1064         {
1065             $permalink='?'.escape(smallhash($link['linkdate']));
1066             $thumb=lazyThumbnail($link['url'],$permalink);
1067             if ($thumb!='') // Only output links which have a thumbnail.
1068             {
1069                 $link['thumbnail']=$thumb; // Thumbnail HTML code.
1070                 $linksToDisplay[]=$link; // Add to array.
1071             }
1072         }
1073
1074         $PAGE = new pageBuilder;
1075         $PAGE->assign('linkcount',count($LINKSDB));
1076         $PAGE->assign('linksToDisplay',$linksToDisplay);
1077         $PAGE->renderPage('picwall');
1078         exit;
1079     }
1080
1081     // -------- Tag cloud
1082     if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=tagcloud'))
1083     {
1084         $tags= $LINKSDB->allTags();
1085
1086         // We sort tags alphabetically, then choose a font size according to count.
1087         // First, find max value.
1088         $maxcount=0; foreach($tags as $key=>$value) $maxcount=max($maxcount,$value);
1089         ksort($tags);
1090         $tagList=array();
1091         foreach($tags as $key=>$value)
1092         // Tag font size scaling: default 15 and 30 logarithm bases affect scaling, 22 and 6 are arbitrary font sizes for max and min sizes.
1093         {
1094             $tagList[$key] = array('count'=>$value,'size'=>log($value, 15) / log($maxcount, 30) * (22-6) + 6);
1095         }
1096         $PAGE = new pageBuilder;
1097         $PAGE->assign('linkcount',count($LINKSDB));
1098         $PAGE->assign('tags',$tagList);
1099         $PAGE->renderPage('tagcloud');
1100         exit;
1101     }
1102
1103     // -------- User clicks on a tag in a link: The tag is added to the list of searched tags (searchtags=...)
1104     if (isset($_GET['addtag']))
1105     {
1106         // Get previous URL (http_referer) and add the tag to the searchtags parameters in query.
1107         if (empty($_SERVER['HTTP_REFERER'])) { header('Location: ?searchtags='.urlencode($_GET['addtag'])); exit; } // In case browser does not send HTTP_REFERER
1108         parse_str(parse_url($_SERVER['HTTP_REFERER'],PHP_URL_QUERY), $params);
1109
1110         // Check if this tag is already in the search query and ignore it if it is.
1111         // Each tag is always separated by a space
1112         $current_tags = explode(' ', $params['searchtags']);
1113         $addtag = true;
1114         foreach ($current_tags as $value) {
1115             if ($value === $_GET['addtag']) {
1116                 $addtag = false;
1117                 break;
1118             }
1119         }
1120         // Append the tag if necessary
1121         if (empty($params['searchtags'])) {
1122             $params['searchtags'] = trim($_GET['addtag']);
1123         }
1124         else if ($addtag) {
1125             $params['searchtags'] = trim($params['searchtags']).' '.trim($_GET['addtag']);
1126         }
1127
1128         unset($params['page']); // We also remove page (keeping the same page has no sense, since the results are different)
1129         header('Location: ?'.http_build_query($params));
1130         exit;
1131     }
1132
1133     // -------- User clicks on a tag in result count: Remove the tag from the list of searched tags (searchtags=...)
1134     if (isset($_GET['removetag']))
1135     {
1136         // Get previous URL (http_referer) and remove the tag from the searchtags parameters in query.
1137         if (empty($_SERVER['HTTP_REFERER'])) { header('Location: ?'); exit; } // In case browser does not send HTTP_REFERER
1138         parse_str(parse_url($_SERVER['HTTP_REFERER'],PHP_URL_QUERY), $params);
1139         if (isset($params['searchtags']))
1140         {
1141             $tags = explode(' ',$params['searchtags']);
1142             $tags=array_diff($tags, array($_GET['removetag'])); // Remove value from array $tags.
1143             if (count($tags)==0) unset($params['searchtags']); else $params['searchtags'] = implode(' ',$tags);
1144             unset($params['page']); // We also remove page (keeping the same page has no sense, since the results are different)
1145         }
1146         header('Location: ?'.http_build_query($params));
1147         exit;
1148     }
1149
1150     // -------- User wants to change the number of links per page (linksperpage=...)
1151     if (isset($_GET['linksperpage']))
1152     {
1153         if (is_numeric($_GET['linksperpage'])) { $_SESSION['LINKS_PER_PAGE']=abs(intval($_GET['linksperpage'])); }
1154         // Make sure the referrer is Shaarli itself.
1155         $referer = '?';
1156         if (!empty($_SERVER['HTTP_REFERER']) && strcmp(parse_url($_SERVER['HTTP_REFERER'],PHP_URL_HOST),$_SERVER['HTTP_HOST'])==0)
1157             $referer = $_SERVER['HTTP_REFERER'];
1158         header('Location: '.$referer);
1159         exit;
1160     }
1161
1162     // -------- User wants to see only private links (toggle)
1163     if (isset($_GET['privateonly']))
1164     {
1165         if (empty($_SESSION['privateonly']))
1166         {
1167             $_SESSION['privateonly']=1; // See only private links
1168         }
1169         else
1170         {
1171             unset($_SESSION['privateonly']); // See all links
1172         }
1173         // Make sure the referrer is Shaarli itself.
1174         $referer = '?';
1175         if (!empty($_SERVER['HTTP_REFERER']) && strcmp(parse_url($_SERVER['HTTP_REFERER'],PHP_URL_HOST),$_SERVER['HTTP_HOST'])==0)
1176             $referer = $_SERVER['HTTP_REFERER'];
1177         header('Location: '.$referer);
1178         exit;
1179     }
1180
1181     // -------- Handle other actions allowed for non-logged in users:
1182     if (!isLoggedIn())
1183     {
1184         // User tries to post new link but is not logged in:
1185         // Show login screen, then redirect to ?post=...
1186         if (isset($_GET['post']))
1187         {
1188             header('Location: ?do=login&post='.urlencode($_GET['post']).(!empty($_GET['title'])?'&title='.urlencode($_GET['title']):'').(!empty($_GET['description'])?'&description='.urlencode($_GET['description']):'').(!empty($_GET['source'])?'&source='.urlencode($_GET['source']):'')); // Redirect to login page, then back to post link.
1189             exit;
1190         }
1191
1192                 // Same case as above except that user tried to access ?do=addlink without being logged in
1193                 // Note: passing empty parameters makes Shaarli generate default URLs and descriptions.
1194                 if (isset($_GET['do']) && $_GET['do'] === 'addlink') {
1195                         header('Location: ?do=login&post=');
1196                         exit;
1197                 }
1198
1199         $PAGE = new pageBuilder;
1200         buildLinkList($PAGE,$LINKSDB); // Compute list of links to display
1201         $PAGE->renderPage('linklist');
1202         exit; // Never remove this one! All operations below are reserved for logged in user.
1203     }
1204
1205     // -------- All other functions are reserved for the registered user:
1206
1207     // -------- Display the Tools menu if requested (import/export/bookmarklet...)
1208     if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=tools'))
1209     {
1210         $PAGE = new pageBuilder;
1211         $PAGE->assign('linkcount',count($LINKSDB));
1212         $PAGE->assign('pageabsaddr',indexUrl());
1213         $PAGE->renderPage('tools');
1214         exit;
1215     }
1216
1217     // -------- User wants to change his/her password.
1218     if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=changepasswd'))
1219     {
1220         if ($GLOBALS['config']['OPEN_SHAARLI']) die('You are not supposed to change a password on an Open Shaarli.');
1221         if (!empty($_POST['setpassword']) && !empty($_POST['oldpassword']))
1222         {
1223             if (!tokenOk($_POST['token'])) die('Wrong token.'); // Go away!
1224
1225             // Make sure old password is correct.
1226             $oldhash = sha1($_POST['oldpassword'].$GLOBALS['login'].$GLOBALS['salt']);
1227             if ($oldhash!=$GLOBALS['hash']) { echo '<script>alert("The old password is not correct.");document.location=\'?do=changepasswd\';</script>'; exit; }
1228             // Save new password
1229             $GLOBALS['salt'] = sha1(uniqid('',true).'_'.mt_rand()); // Salt renders rainbow-tables attacks useless.
1230             $GLOBALS['hash'] = sha1($_POST['setpassword'].$GLOBALS['login'].$GLOBALS['salt']);
1231             writeConfig();
1232             echo '<script>alert("Your password has been changed.");document.location=\'?do=tools\';</script>';
1233             exit;
1234         }
1235         else // show the change password form.
1236         {
1237             $PAGE = new pageBuilder;
1238             $PAGE->assign('linkcount',count($LINKSDB));
1239             $PAGE->assign('token',getToken());
1240             $PAGE->renderPage('changepassword');
1241             exit;
1242         }
1243     }
1244
1245     // -------- User wants to change configuration
1246     if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=configure'))
1247     {
1248         if (!empty($_POST['title']) )
1249         {
1250             if (!tokenOk($_POST['token'])) die('Wrong token.'); // Go away!
1251             $tz = 'UTC';
1252             if (!empty($_POST['continent']) && !empty($_POST['city']))
1253                 if (isTZvalid($_POST['continent'],$_POST['city']))
1254                     $tz = $_POST['continent'].'/'.$_POST['city'];
1255             $GLOBALS['timezone'] = $tz;
1256             $GLOBALS['title']=$_POST['title'];
1257             $GLOBALS['titleLink']=$_POST['titleLink'];
1258             $GLOBALS['redirector']=$_POST['redirector'];
1259             $GLOBALS['disablesessionprotection']=!empty($_POST['disablesessionprotection']);
1260             $GLOBALS['disablejquery']=!empty($_POST['disablejquery']);
1261             $GLOBALS['privateLinkByDefault']=!empty($_POST['privateLinkByDefault']);
1262             $GLOBALS['config']['ENABLE_RSS_PERMALINKS']= !empty($_POST['enableRssPermalinks']);
1263             $GLOBALS['config']['ENABLE_UPDATECHECK'] = !empty($_POST['updateCheck']);
1264             $GLOBALS['config']['HIDE_PUBLIC_LINKS'] = !empty($_POST['hidePublicLinks']);
1265             writeConfig();
1266             echo '<script>alert("Configuration was saved.");document.location=\'?do=tools\';</script>';
1267             exit;
1268         }
1269         else // Show the configuration form.
1270         {
1271             $PAGE = new pageBuilder;
1272             $PAGE->assign('linkcount',count($LINKSDB));
1273             $PAGE->assign('token',getToken());
1274             $PAGE->assign('title', empty($GLOBALS['title']) ? '' : $GLOBALS['title'] );
1275             $PAGE->assign('redirector', empty($GLOBALS['redirector']) ? '' : $GLOBALS['redirector'] );
1276             list($timezone_form,$timezone_js) = templateTZform($GLOBALS['timezone']);
1277             $PAGE->assign('timezone_form',$timezone_form); // FIXME: Put entire tz form generation in template?
1278             $PAGE->assign('timezone_js',$timezone_js);
1279             $PAGE->renderPage('configure');
1280             exit;
1281         }
1282     }
1283
1284     // -------- User wants to rename a tag or delete it
1285     if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=changetag'))
1286     {
1287         if (empty($_POST['fromtag']))
1288         {
1289             $PAGE = new pageBuilder;
1290             $PAGE->assign('linkcount',count($LINKSDB));
1291             $PAGE->assign('token',getToken());
1292             $PAGE->assign('tags', $LINKSDB->allTags());
1293             $PAGE->renderPage('changetag');
1294             exit;
1295         }
1296         if (!tokenOk($_POST['token'])) die('Wrong token.');
1297
1298         // Delete a tag:
1299         if (!empty($_POST['deletetag']) && !empty($_POST['fromtag']))
1300         {
1301             $needle=trim($_POST['fromtag']);
1302             $linksToAlter = $LINKSDB->filterTags($needle,true); // True for case-sensitive tag search.
1303             foreach($linksToAlter as $key=>$value)
1304             {
1305                 $tags = explode(' ',trim($value['tags']));
1306                 unset($tags[array_search($needle,$tags)]); // Remove tag.
1307                 $value['tags']=trim(implode(' ',$tags));
1308                 $LINKSDB[$key]=$value;
1309             }
1310             $LINKSDB->savedb(); // Save to disk.
1311             echo '<script>alert("Tag was removed from '.count($linksToAlter).' links.");document.location=\'?\';</script>';
1312             exit;
1313         }
1314
1315         // Rename a tag:
1316         if (!empty($_POST['renametag']) && !empty($_POST['fromtag']) && !empty($_POST['totag']))
1317         {
1318             $needle=trim($_POST['fromtag']);
1319             $linksToAlter = $LINKSDB->filterTags($needle,true); // true for case-sensitive tag search.
1320             foreach($linksToAlter as $key=>$value)
1321             {
1322                 $tags = explode(' ',trim($value['tags']));
1323                 $tags[array_search($needle,$tags)] = trim($_POST['totag']); // Replace tags value.
1324                 $value['tags']=trim(implode(' ',$tags));
1325                 $LINKSDB[$key]=$value;
1326             }
1327             $LINKSDB->savedb(); // Save to disk.
1328             echo '<script>alert("Tag was renamed in '.count($linksToAlter).' links.");document.location=\'?searchtags='.urlencode($_POST['totag']).'\';</script>';
1329             exit;
1330         }
1331     }
1332
1333     // -------- User wants to add a link without using the bookmarklet: Show form.
1334     if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=addlink'))
1335     {
1336         $PAGE = new pageBuilder;
1337         $PAGE->assign('linkcount',count($LINKSDB));
1338         $PAGE->renderPage('addlink');
1339         exit;
1340     }
1341
1342     // -------- User clicked the "Save" button when editing a link: Save link to database.
1343     if (isset($_POST['save_edit']))
1344     {
1345         if (!tokenOk($_POST['token'])) die('Wrong token.'); // Go away!
1346         $tags = trim(preg_replace('/\s\s+/',' ', $_POST['lf_tags'])); // Remove multiple spaces.
1347         $linkdate=$_POST['lf_linkdate'];
1348         $url = trim($_POST['lf_url']);
1349         if (!startsWith($url,'http:') && !startsWith($url,'https:') && !startsWith($url,'ftp:') && !startsWith($url,'magnet:') && !startsWith($url,'?') && !startsWith($url,'javascript:'))
1350             $url = 'http://'.$url;
1351         $link = array('title'=>trim($_POST['lf_title']),'url'=>$url,'description'=>trim($_POST['lf_description']),'private'=>(isset($_POST['lf_private']) ? 1 : 0),
1352                       'linkdate'=>$linkdate,'tags'=>str_replace(',',' ',$tags));
1353         if ($link['title']=='') $link['title']=$link['url']; // If title is empty, use the URL as title.
1354         $LINKSDB[$linkdate] = $link;
1355         $LINKSDB->savedb(); // Save to disk.
1356         pubsubhub();
1357
1358         // If we are called from the bookmarklet, we must close the popup:
1359         if (isset($_GET['source']) && ($_GET['source']=='bookmarklet' || $_GET['source']=='firefoxsocialapi')) { echo '<script>self.close();</script>'; exit; }
1360         $returnurl = ( isset($_POST['returnurl']) ? $_POST['returnurl'] : '?' );
1361         $returnurl .= '#'.smallHash($linkdate);  // Scroll to the link which has been edited.
1362         if (strstr($returnurl, "do=addlink")) { $returnurl = '?'; } //if we come from ?do=addlink, set returnurl to homepage instead
1363         header('Location: '.$returnurl); // After saving the link, redirect to the page the user was on.
1364         exit;
1365     }
1366
1367     // -------- User clicked the "Cancel" button when editing a link.
1368     if (isset($_POST['cancel_edit']))
1369     {
1370         // If we are called from the bookmarklet, we must close the popup:
1371         if (isset($_GET['source']) && ($_GET['source']=='bookmarklet' || $_GET['source']=='firefoxsocialapi')) { echo '<script>self.close();</script>'; exit; }
1372         $returnurl = ( isset($_POST['returnurl']) ? $_POST['returnurl'] : '?' );
1373         $returnurl .= '#'.smallHash($_POST['lf_linkdate']);  // Scroll to the link which has been edited.
1374         header('Location: '.$returnurl); // After canceling, redirect to the page the user was on.
1375         exit;
1376     }
1377
1378     // -------- User clicked the "Delete" button when editing a link: Delete link from database.
1379     if (isset($_POST['delete_link']))
1380     {
1381         if (!tokenOk($_POST['token'])) die('Wrong token.');
1382         // We do not need to ask for confirmation:
1383         // - confirmation is handled by JavaScript
1384         // - we are protected from XSRF by the token.
1385         $linkdate=$_POST['lf_linkdate'];
1386         unset($LINKSDB[$linkdate]);
1387         $LINKSDB->savedb(); // save to disk
1388
1389         // If we are called from the bookmarklet, we must close the popup:
1390         if (isset($_GET['source']) && ($_GET['source']=='bookmarklet' || $_GET['source']=='firefoxsocialapi')) { echo '<script>self.close();</script>'; exit; }
1391         // Pick where we're going to redirect
1392         // =============================================================
1393         // Basically, we can't redirect to where we were previously if it was a permalink
1394         // or an edit_link, because it would 404.
1395         // Cases:
1396         //    - /             : nothing in $_GET, redirect to self
1397         //    - /?page        : redirect to self
1398         //    - /?searchterm  : redirect to self (there might be other links)
1399         //    - /?searchtags  : redirect to self
1400         //    - /permalink    : redirect to / (the link does not exist anymore)
1401         //    - /?edit_link   : redirect to / (the link does not exist anymore)
1402         // PHP treats the permalink as a $_GET variable, so we need to check if every condition for self
1403         // redirect is not satisfied, and only then redirect to /
1404         $location = "?";
1405         // Self redirection
1406         if (count($_GET) == 0    ||
1407             isset($_GET['page']) ||
1408             isset($_GET['searchterm']) ||
1409             isset($_GET['searchtags'])) {
1410
1411             if (isset($_POST['returnurl'])) {
1412                 $location = $_POST['returnurl']; // Handle redirects given by the form
1413             }
1414
1415             if ($location === "?" &&
1416                 isset($_SERVER['HTTP_REFERER'])) { // Handle HTTP_REFERER in case we're not coming from the same place.
1417                 $location = $_SERVER['HTTP_REFERER'];
1418             }
1419         }
1420
1421         header('Location: ' . $location); // After deleting the link, redirect to appropriate location
1422         exit;
1423     }
1424
1425     // -------- User clicked the "EDIT" button on a link: Display link edit form.
1426     if (isset($_GET['edit_link']))
1427     {
1428         $link = $LINKSDB[$_GET['edit_link']];  // Read database
1429         if (!$link) { header('Location: ?'); exit; } // Link not found in database.
1430         $PAGE = new pageBuilder;
1431         $PAGE->assign('linkcount',count($LINKSDB));
1432         $PAGE->assign('link',$link);
1433         $PAGE->assign('link_is_new',false);
1434         $PAGE->assign('token',getToken()); // XSRF protection.
1435         $PAGE->assign('http_referer',(isset($_SERVER['HTTP_REFERER']) ? escape($_SERVER['HTTP_REFERER']) : ''));
1436         $PAGE->assign('tags', $LINKSDB->allTags());
1437         $PAGE->renderPage('editlink');
1438         exit;
1439     }
1440
1441     // -------- User want to post a new link: Display link edit form.
1442     if (isset($_GET['post']))
1443     {
1444         $url=$_GET['post'];
1445
1446
1447         // We remove the annoying parameters added by FeedBurner, GoogleFeedProxy, Facebook...
1448         $annoyingpatterns = array('/[\?&]utm_source=[^&]*/',
1449             '/[\?&]utm_campaign=[^&]*/',
1450             '/[\?&]utm_medium=[^&]*/',
1451             '/#xtor=RSS-[^&]*/',
1452             '/[\?&]fb_[^&]*/',
1453             '/[\?&]__scoop[^&]*/',
1454             '/#tk\.rss_all\?/',
1455             '/[\?&]action_ref_map=[^&]*/',
1456             '/[\?&]action_type_map=[^&]*/',
1457             '/[\?&]action_object_map=[^&]*/',
1458             '/[\?&]utm_content=[^&]*/',
1459             '/[\?&]fb=[^&]*/',
1460             '/[\?&]xtor=[^&]*/'
1461             );
1462         foreach($annoyingpatterns as $pattern)
1463         {
1464             $url = preg_replace($pattern, "", $url);
1465         }
1466
1467         $link_is_new = false;
1468         $link = $LINKSDB->getLinkFromUrl($url); // Check if URL is not already in database (in this case, we will edit the existing link)
1469         if (!$link)
1470         {
1471             $link_is_new = true;  // This is a new link
1472             $linkdate = strval(date('Ymd_His'));
1473             $title = (empty($_GET['title']) ? '' : $_GET['title'] ); // Get title if it was provided in URL (by the bookmarklet).
1474             $description = (empty($_GET['description']) ? '' : $_GET['description']); // Get description if it was provided in URL (by the bookmarklet). [Bronco added that]
1475             $tags = (empty($_GET['tags']) ? '' : $_GET['tags'] ); // Get tags if it was provided in URL
1476             $private = (!empty($_GET['private']) && $_GET['private'] === "1" ? 1 : 0); // Get private if it was provided in URL
1477             if (($url!='') && parse_url($url,PHP_URL_SCHEME)=='') $url = 'http://'.$url;
1478             // If this is an HTTP link, we try go get the page to extract the title (otherwise we will to straight to the edit form.)
1479             if (empty($title) && parse_url($url,PHP_URL_SCHEME)=='http')
1480             {
1481                 list($status,$headers,$data) = getHTTP($url,4); // Short timeout to keep the application responsive.
1482                 // FIXME: Decode charset according to specified in either 1) HTTP response headers or 2) <head> in html
1483                 if (strpos($status,'200 OK')!==false)
1484                                          {
1485                         // Look for charset in html header.
1486                                                 preg_match('#<meta .*charset=.*>#Usi', $data, $meta);
1487
1488                                                 // If found, extract encoding.
1489                                                 if (!empty($meta[0]))
1490                                                 {
1491                                                         // Get encoding specified in header.
1492                                                         preg_match('#charset="?(.*)"#si', $meta[0], $enc);
1493                                                         // If charset not found, use utf-8.
1494                                                         $html_charset = (!empty($enc[1])) ? strtolower($enc[1]) : 'utf-8';
1495                                                 }
1496                                                 else { $html_charset = 'utf-8'; }
1497
1498                                                 // Extract title
1499                                                 $title = html_extract_title($data);
1500                                                 if (!empty($title))
1501                                                 {
1502                                                         // Re-encode title in utf-8 if necessary.
1503                                                         $title = ($html_charset == 'iso-8859-1') ? utf8_encode($title) : $title;
1504                                                 }
1505                                         }
1506             }
1507             if ($url=='') // In case of empty URL, this is just a text (with a link that points to itself)
1508             {
1509                 $url='?'.smallHash($linkdate);
1510                 $title='Note: ';
1511             }
1512             $link = array('linkdate'=>$linkdate,'title'=>$title,'url'=>$url,'description'=>$description,'tags'=>$tags,'private'=>$private);
1513         }
1514
1515         $PAGE = new pageBuilder;
1516         $PAGE->assign('linkcount',count($LINKSDB));
1517         $PAGE->assign('link',$link);
1518         $PAGE->assign('link_is_new',$link_is_new);
1519         $PAGE->assign('token',getToken()); // XSRF protection.
1520         $PAGE->assign('http_referer',(isset($_SERVER['HTTP_REFERER']) ? $_SERVER['HTTP_REFERER'] : ''));
1521         $PAGE->assign('source',(isset($_GET['source']) ? $_GET['source'] : ''));
1522         $PAGE->assign('tags', $LINKSDB->allTags());
1523         $PAGE->renderPage('editlink');
1524         exit;
1525     }
1526
1527     // -------- Export as Netscape Bookmarks HTML file.
1528     if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=export'))
1529     {
1530         if (empty($_GET['what']))
1531         {
1532             $PAGE = new pageBuilder;
1533             $PAGE->assign('linkcount',count($LINKSDB));
1534             $PAGE->renderPage('export');
1535             exit;
1536         }
1537         $exportWhat=$_GET['what'];
1538         if (!array_intersect(array('all','public','private'),array($exportWhat))) die('What are you trying to export???');
1539
1540         header('Content-Type: text/html; charset=utf-8');
1541         header('Content-disposition: attachment; filename=bookmarks_'.$exportWhat.'_'.strval(date('Ymd_His')).'.html');
1542         $currentdate=date('Y/m/d H:i:s');
1543         echo <<<HTML
1544 <!DOCTYPE NETSCAPE-Bookmark-file-1>
1545 <!-- This is an automatically generated file.
1546      It will be read and overwritten.
1547      DO NOT EDIT! -->
1548 <!-- Shaarli {$exportWhat} bookmarks export on {$currentdate} -->
1549 <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=UTF-8">
1550 <TITLE>Bookmarks</TITLE>
1551 <H1>Bookmarks</H1>
1552 HTML;
1553         foreach($LINKSDB as $link)
1554         {
1555             if ($exportWhat=='all' ||
1556                ($exportWhat=='private' && $link['private']!=0) ||
1557                ($exportWhat=='public' && $link['private']==0))
1558             {
1559                 echo '<DT><A HREF="'.$link['url'].'" ADD_DATE="'.linkdate2timestamp($link['linkdate']).'" PRIVATE="'.$link['private'].'"';
1560                 if ($link['tags']!='') echo ' TAGS="'.str_replace(' ',',',$link['tags']).'"';
1561                 echo '>'.$link['title']."</A>\n";
1562                 if ($link['description']!='') echo '<DD>'.$link['description']."\n";
1563             }
1564         }
1565                 exit;
1566     }
1567
1568     // -------- User is uploading a file for import
1569     if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=upload'))
1570     {
1571         // If file is too big, some form field may be missing.
1572         if (!isset($_POST['token']) || (!isset($_FILES)) || (isset($_FILES['filetoupload']['size']) && $_FILES['filetoupload']['size']==0))
1573         {
1574             $returnurl = ( empty($_SERVER['HTTP_REFERER']) ? '?' : $_SERVER['HTTP_REFERER'] );
1575             echo '<script>alert("The file you are trying to upload is probably bigger than what this webserver can accept ('.getMaxFileSize().' bytes). Please upload in smaller chunks.");document.location=\''.escape($returnurl).'\';</script>';
1576             exit;
1577         }
1578         if (!tokenOk($_POST['token'])) die('Wrong token.');
1579         importFile();
1580         exit;
1581     }
1582
1583     // -------- Show upload/import dialog:
1584     if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=import'))
1585     {
1586         $PAGE = new pageBuilder;
1587         $PAGE->assign('linkcount',count($LINKSDB));
1588         $PAGE->assign('token',getToken());
1589         $PAGE->assign('maxfilesize',getMaxFileSize());
1590         $PAGE->renderPage('import');
1591         exit;
1592     }
1593
1594     // -------- Otherwise, simply display search form and links:
1595     $PAGE = new pageBuilder;
1596     buildLinkList($PAGE,$LINKSDB); // Compute list of links to display
1597     $PAGE->renderPage('linklist');
1598     exit;
1599 }
1600
1601 // -----------------------------------------------------------------------------------------------
1602 // Process the import file form.
1603 function importFile()
1604 {
1605     if (!(isLoggedIn() || $GLOBALS['config']['OPEN_SHAARLI'])) { die('Not allowed.'); }
1606     $LINKSDB = new LinkDB(
1607         isLoggedIn() || $GLOBALS['config']['OPEN_SHAARLI'],
1608         $GLOBALS['config']['HIDE_PUBLIC_LINKS']
1609     );
1610     $filename=$_FILES['filetoupload']['name'];
1611     $filesize=$_FILES['filetoupload']['size'];
1612     $data=file_get_contents($_FILES['filetoupload']['tmp_name']);
1613     $private = (empty($_POST['private']) ? 0 : 1); // Should the links be imported as private?
1614     $overwrite = !empty($_POST['overwrite']) ; // Should the imported links overwrite existing ones?
1615     $import_count=0;
1616
1617     // Sniff file type:
1618     $type='unknown';
1619     if (startsWith($data,'<!DOCTYPE NETSCAPE-Bookmark-file-1>')) $type='netscape'; // Netscape bookmark file (aka Firefox).
1620
1621     // Then import the bookmarks.
1622     if ($type=='netscape')
1623     {
1624         // This is a standard Netscape-style bookmark file.
1625         // This format is supported by all browsers (except IE, of course), also Delicious, Diigo and others.
1626         foreach(explode('<DT>',$data) as $html) // explode is very fast
1627         {
1628             $link = array('linkdate'=>'','title'=>'','url'=>'','description'=>'','tags'=>'','private'=>0);
1629             $d = explode('<DD>',$html);
1630             if (startswith($d[0],'<A '))
1631             {
1632                 $link['description'] = (isset($d[1]) ? html_entity_decode(trim($d[1]),ENT_QUOTES,'UTF-8') : '');  // Get description (optional)
1633                 preg_match('!<A .*?>(.*?)</A>!i',$d[0],$matches); $link['title'] = (isset($matches[1]) ? trim($matches[1]) : '');  // Get title
1634                 $link['title'] = html_entity_decode($link['title'],ENT_QUOTES,'UTF-8');
1635                 preg_match_all('! ([A-Z_]+)=\"(.*?)"!i',$html,$matches,PREG_SET_ORDER);  // Get all other attributes
1636                 $raw_add_date=0;
1637                 foreach($matches as $m)
1638                 {
1639                     $attr=$m[1]; $value=$m[2];
1640                     if ($attr=='HREF') $link['url']=html_entity_decode($value,ENT_QUOTES,'UTF-8');
1641                     elseif ($attr=='ADD_DATE')
1642                     {
1643                         $raw_add_date=intval($value);
1644                         if ($raw_add_date>30000000000) $raw_add_date/=1000;     //If larger than year 2920, then was likely stored in milliseconds instead of seconds
1645                     }
1646                     elseif ($attr=='PRIVATE') $link['private']=($value=='0'?0:1);
1647                     elseif ($attr=='TAGS') $link['tags']=html_entity_decode(str_replace(',',' ',$value),ENT_QUOTES,'UTF-8');
1648                 }
1649                 if ($link['url']!='')
1650                 {
1651                     if ($private==1) $link['private']=1;
1652                     $dblink = $LINKSDB->getLinkFromUrl($link['url']); // See if the link is already in database.
1653                     if ($dblink==false)
1654                     {  // Link not in database, let's import it...
1655                        if (empty($raw_add_date)) $raw_add_date=time(); // In case of shitty bookmark file with no ADD_DATE
1656
1657                        // Make sure date/time is not already used by another link.
1658                        // (Some bookmark files have several different links with the same ADD_DATE)
1659                        // We increment date by 1 second until we find a date which is not used in DB.
1660                        // (so that links that have the same date/time are more or less kept grouped by date, but do not conflict.)
1661                        while (!empty($LINKSDB[date('Ymd_His',$raw_add_date)])) { $raw_add_date++; }// Yes, I know it's ugly.
1662                        $link['linkdate']=date('Ymd_His',$raw_add_date);
1663                        $LINKSDB[$link['linkdate']] = $link;
1664                        $import_count++;
1665                     }
1666                     else // Link already present in database.
1667                     {
1668                         if ($overwrite)
1669                         {   // If overwrite is required, we import link data, except date/time.
1670                             $link['linkdate']=$dblink['linkdate'];
1671                             $LINKSDB[$link['linkdate']] = $link;
1672                             $import_count++;
1673                         }
1674                     }
1675
1676                 }
1677             }
1678         }
1679         $LINKSDB->savedb();
1680
1681         echo '<script>alert("File '.json_encode($filename).' ('.$filesize.' bytes) was successfully processed: '.$import_count.' links imported.");document.location=\'?\';</script>';
1682     }
1683     else
1684     {
1685         echo '<script>alert("File '.json_encode($filename).' ('.$filesize.' bytes) has an unknown file format. Nothing was imported.");document.location=\'?\';</script>';
1686     }
1687 }
1688
1689 // -----------------------------------------------------------------------------------------------
1690 // Template for the list of links (<div id="linklist">)
1691 // This function fills all the necessary fields in the $PAGE for the template 'linklist.html'
1692 function buildLinkList($PAGE,$LINKSDB)
1693 {
1694     // ---- Filter link database according to parameters
1695     $linksToDisplay=array();
1696     $search_type='';
1697     $search_crits='';
1698     if (isset($_GET['searchterm'])) // Fulltext search
1699     {
1700         $linksToDisplay = $LINKSDB->filterFulltext(trim($_GET['searchterm']));
1701         $search_crits=escape(trim($_GET['searchterm']));
1702         $search_type='fulltext';
1703     }
1704     elseif (isset($_GET['searchtags'])) // Search by tag
1705     {
1706         $linksToDisplay = $LINKSDB->filterTags(trim($_GET['searchtags']));
1707         $search_crits=explode(' ',escape(trim($_GET['searchtags'])));
1708         $search_type='tags';
1709     }
1710     elseif (isset($_SERVER['QUERY_STRING']) && preg_match('/[a-zA-Z0-9-_@]{6}(&.+?)?/',$_SERVER['QUERY_STRING'])) // Detect smallHashes in URL
1711     {
1712         $linksToDisplay = $LINKSDB->filterSmallHash(substr(trim($_SERVER["QUERY_STRING"], '/'),0,6));
1713         if (count($linksToDisplay)==0)
1714         {
1715             header($_SERVER["SERVER_PROTOCOL"]." 404 Not Found");
1716             echo '<h1>404 Not found.</h1>Oh crap. The link you are trying to reach does not exist or has been deleted.';
1717             echo '<br>You would mind <a href="?">clicking here</a>?';
1718             exit;
1719         }
1720         $search_type='permalink';
1721     }
1722     else
1723         $linksToDisplay = $LINKSDB;  // Otherwise, display without filtering.
1724
1725
1726     // Option: Show only private links
1727     if (!empty($_SESSION['privateonly']))
1728     {
1729         $tmp = array();
1730         foreach($linksToDisplay as $linkdate=>$link)
1731         {
1732             if ($link['private']!=0) $tmp[$linkdate]=$link;
1733         }
1734         $linksToDisplay=$tmp;
1735     }
1736
1737     // ---- Handle paging.
1738     /* Can someone explain to me why you get the following error when using array_keys() on an object which implements the interface ArrayAccess???
1739        "Warning: array_keys() expects parameter 1 to be array, object given in ... "
1740        If my class implements ArrayAccess, why won't array_keys() accept it ?  ( $keys=array_keys($linksToDisplay); )
1741     */
1742     $keys=array(); foreach($linksToDisplay as $key=>$value) { $keys[]=$key; } // Stupid and ugly. Thanks PHP.
1743
1744     // If there is only a single link, we change on-the-fly the title of the page.
1745     if (count($linksToDisplay)==1) $GLOBALS['pagetitle'] = $linksToDisplay[$keys[0]]['title'].' - '.$GLOBALS['title'];
1746
1747     // Select articles according to paging.
1748     $pagecount = ceil(count($keys)/$_SESSION['LINKS_PER_PAGE']);
1749     $pagecount = ($pagecount==0 ? 1 : $pagecount);
1750     $page=( empty($_GET['page']) ? 1 : intval($_GET['page']));
1751     $page = ( $page<1 ? 1 : $page );
1752     $page = ( $page>$pagecount ? $pagecount : $page );
1753     $i = ($page-1)*$_SESSION['LINKS_PER_PAGE']; // Start index.
1754     $end = $i+$_SESSION['LINKS_PER_PAGE'];
1755     $linkDisp=array(); // Links to display
1756     while ($i<$end && $i<count($keys))
1757     {
1758         $link = $linksToDisplay[$keys[$i]];
1759         $link['description']=nl2br(keepMultipleSpaces(text2clickable($link['description'])));
1760         $title=$link['title'];
1761         $classLi =  $i%2!=0 ? '' : 'publicLinkHightLight';
1762         $link['class'] = ($link['private']==0 ? $classLi : 'private');
1763         $link['timestamp']=linkdate2timestamp($link['linkdate']);
1764         $taglist = explode(' ',$link['tags']);
1765         uasort($taglist, 'strcasecmp');
1766         $link['taglist']=$taglist;
1767
1768         if ($link["url"][0] === '?' && // Check for both signs of a note: starting with ? and 7 chars long. I doubt that you'll post any links that look like this.
1769             strlen($link["url"]) === 7) {
1770             $link["url"] = indexUrl() . $link["url"];
1771         }
1772
1773         $linkDisp[$keys[$i]] = $link;
1774         $i++;
1775     }
1776
1777     // Compute paging navigation
1778     $searchterm= ( empty($_GET['searchterm']) ? '' : '&searchterm='.$_GET['searchterm'] );
1779     $searchtags= ( empty($_GET['searchtags']) ? '' : '&searchtags='.$_GET['searchtags'] );
1780     $paging='';
1781     $previous_page_url=''; if ($i!=count($keys)) $previous_page_url='?page='.($page+1).$searchterm.$searchtags;
1782     $next_page_url='';if ($page>1) $next_page_url='?page='.($page-1).$searchterm.$searchtags;
1783
1784     $token = ''; if (isLoggedIn()) $token=getToken();
1785
1786     // Fill all template fields.
1787     $PAGE->assign('linkcount',count($LINKSDB));
1788     $PAGE->assign('previous_page_url',$previous_page_url);
1789     $PAGE->assign('next_page_url',$next_page_url);
1790     $PAGE->assign('page_current',$page);
1791     $PAGE->assign('page_max',$pagecount);
1792     $PAGE->assign('result_count',count($linksToDisplay));
1793     $PAGE->assign('search_type',$search_type);
1794     $PAGE->assign('search_crits',$search_crits);
1795     $PAGE->assign('redirector',empty($GLOBALS['redirector']) ? '' : $GLOBALS['redirector']); // Optional redirector URL.
1796     $PAGE->assign('token',$token);
1797     $PAGE->assign('links',$linkDisp);
1798     $PAGE->assign('tags', $LINKSDB->allTags());
1799     return;
1800 }
1801
1802 // Compute the thumbnail for a link.
1803 //
1804 // With a link to the original URL.
1805 // Understands various services (youtube.com...)
1806 // Input: $url = URL for which the thumbnail must be found.
1807 //        $href = if provided, this URL will be followed instead of $url
1808 // Returns an associative array with thumbnail attributes (src,href,width,height,style,alt)
1809 // Some of them may be missing.
1810 // Return an empty array if no thumbnail available.
1811 function computeThumbnail($url,$href=false)
1812 {
1813     if (!$GLOBALS['config']['ENABLE_THUMBNAILS']) return array();
1814     if ($href==false) $href=$url;
1815
1816     // For most hosts, the URL of the thumbnail can be easily deduced from the URL of the link.
1817     // (e.g. http://www.youtube.com/watch?v=spVypYk4kto --->  http://img.youtube.com/vi/spVypYk4kto/default.jpg )
1818     //                                     ^^^^^^^^^^^                                 ^^^^^^^^^^^
1819     $domain = parse_url($url,PHP_URL_HOST);
1820     if ($domain=='youtube.com' || $domain=='www.youtube.com')
1821     {
1822         parse_str(parse_url($url,PHP_URL_QUERY), $params); // Extract video ID and get thumbnail
1823         if (!empty($params['v'])) return array('src'=>'https://img.youtube.com/vi/'.$params['v'].'/default.jpg',
1824                                                'href'=>$href,'width'=>'120','height'=>'90','alt'=>'YouTube thumbnail');
1825     }
1826     if ($domain=='youtu.be') // Youtube short links
1827     {
1828         $path = parse_url($url,PHP_URL_PATH);
1829         return array('src'=>'https://img.youtube.com/vi'.$path.'/default.jpg',
1830                      'href'=>$href,'width'=>'120','height'=>'90','alt'=>'YouTube thumbnail');
1831     }
1832     if ($domain=='pix.toile-libre.org') // pix.toile-libre.org image hosting
1833     {
1834         parse_str(parse_url($url,PHP_URL_QUERY), $params); // Extract image filename.
1835         if (!empty($params) && !empty($params['img'])) return array('src'=>'http://pix.toile-libre.org/upload/thumb/'.urlencode($params['img']),
1836                                                                     'href'=>$href,'style'=>'max-width:120px; max-height:150px','alt'=>'pix.toile-libre.org thumbnail');
1837     }
1838
1839     if ($domain=='imgur.com')
1840     {
1841         $path = parse_url($url,PHP_URL_PATH);
1842         if (startsWith($path,'/a/')) return array(); // Thumbnails for albums are not available.
1843         if (startsWith($path,'/r/')) return array('src'=>'https://i.imgur.com/'.basename($path).'s.jpg',
1844                                                   'href'=>$href,'width'=>'90','height'=>'90','alt'=>'imgur.com thumbnail');
1845         if (startsWith($path,'/gallery/')) return array('src'=>'https://i.imgur.com'.substr($path,8).'s.jpg',
1846                                                         'href'=>$href,'width'=>'90','height'=>'90','alt'=>'imgur.com thumbnail');
1847
1848         if (substr_count($path,'/')==1) return array('src'=>'https://i.imgur.com/'.substr($path,1).'s.jpg',
1849                                                      'href'=>$href,'width'=>'90','height'=>'90','alt'=>'imgur.com thumbnail');
1850     }
1851     if ($domain=='i.imgur.com')
1852     {
1853         $pi = pathinfo(parse_url($url,PHP_URL_PATH));
1854         if (!empty($pi['filename'])) return array('src'=>'https://i.imgur.com/'.$pi['filename'].'s.jpg',
1855                                                   'href'=>$href,'width'=>'90','height'=>'90','alt'=>'imgur.com thumbnail');
1856     }
1857     if ($domain=='dailymotion.com' || $domain=='www.dailymotion.com')
1858     {
1859         if (strpos($url,'dailymotion.com/video/')!==false)
1860         {
1861             $thumburl=str_replace('dailymotion.com/video/','dailymotion.com/thumbnail/video/',$url);
1862             return array('src'=>$thumburl,
1863                          'href'=>$href,'width'=>'120','style'=>'height:auto;','alt'=>'DailyMotion thumbnail');
1864         }
1865     }
1866     if (endsWith($domain,'.imageshack.us'))
1867     {
1868         $ext=strtolower(pathinfo($url,PATHINFO_EXTENSION));
1869         if ($ext=='jpg' || $ext=='jpeg' || $ext=='png' || $ext=='gif')
1870         {
1871             $thumburl = substr($url,0,strlen($url)-strlen($ext)).'th.'.$ext;
1872             return array('src'=>$thumburl,
1873                          'href'=>$href,'width'=>'120','style'=>'height:auto;','alt'=>'imageshack.us thumbnail');
1874         }
1875     }
1876
1877     // Some other hosts are SLOW AS HELL and usually require an extra HTTP request to get the thumbnail URL.
1878     // So we deport the thumbnail generation in order not to slow down page generation
1879     // (and we also cache the thumbnail)
1880
1881     if (!$GLOBALS['config']['ENABLE_LOCALCACHE']) return array(); // If local cache is disabled, no thumbnails for services which require the use a local cache.
1882
1883     if ($domain=='flickr.com' || endsWith($domain,'.flickr.com')
1884         || $domain=='vimeo.com'
1885         || $domain=='ted.com' || endsWith($domain,'.ted.com')
1886         || $domain=='xkcd.com' || endsWith($domain,'.xkcd.com')
1887     )
1888     {
1889         if ($domain=='vimeo.com')
1890         {   // Make sure this vimeo URL points to a video (/xxx... where xxx is numeric)
1891             $path = parse_url($url,PHP_URL_PATH);
1892             if (!preg_match('!/\d+.+?!',$path)) return array(); // This is not a single video URL.
1893         }
1894         if ($domain=='xkcd.com' || endsWith($domain,'.xkcd.com'))
1895         {   // Make sure this URL points to a single comic (/xxx... where xxx is numeric)
1896             $path = parse_url($url,PHP_URL_PATH);
1897             if (!preg_match('!/\d+.+?!',$path)) return array();
1898         }
1899         if ($domain=='ted.com' || endsWith($domain,'.ted.com'))
1900         {   // Make sure this TED URL points to a video (/talks/...)
1901             $path = parse_url($url,PHP_URL_PATH);
1902             if ("/talks/" !== substr($path,0,7)) return array(); // This is not a single video URL.
1903         }
1904         $sign = hash_hmac('sha256', $url, $GLOBALS['salt']); // We use the salt to sign data (it's random, secret, and specific to each installation)
1905         return array('src'=>indexUrl().'?do=genthumbnail&hmac='.$sign.'&url='.urlencode($url),
1906                      'href'=>$href,'width'=>'120','style'=>'height:auto;','alt'=>'thumbnail');
1907     }
1908
1909     // For all other, we try to make a thumbnail of links ending with .jpg/jpeg/png/gif
1910     // Technically speaking, we should download ALL links and check their Content-Type to see if they are images.
1911     // But using the extension will do.
1912     $ext=strtolower(pathinfo($url,PATHINFO_EXTENSION));
1913     if ($ext=='jpg' || $ext=='jpeg' || $ext=='png' || $ext=='gif')
1914     {
1915         $sign = hash_hmac('sha256', $url, $GLOBALS['salt']); // We use the salt to sign data (it's random, secret, and specific to each installation)
1916         return array('src'=>indexUrl().'?do=genthumbnail&hmac='.$sign.'&url='.urlencode($url),
1917                      'href'=>$href,'width'=>'120','style'=>'height:auto;','alt'=>'thumbnail');
1918     }
1919     return array(); // No thumbnail.
1920
1921 }
1922
1923
1924 // Returns the HTML code to display a thumbnail for a link
1925 // with a link to the original URL.
1926 // Understands various services (youtube.com...)
1927 // Input: $url = URL for which the thumbnail must be found.
1928 //        $href = if provided, this URL will be followed instead of $url
1929 // Returns '' if no thumbnail available.
1930 function thumbnail($url,$href=false)
1931 {
1932     $t = computeThumbnail($url,$href);
1933     if (count($t)==0) return ''; // Empty array = no thumbnail for this URL.
1934
1935     $html='<a href="'.escape($t['href']).'"><img src="'.escape($t['src']).'"';
1936     if (!empty($t['width']))  $html.=' width="'.escape($t['width']).'"';
1937     if (!empty($t['height'])) $html.=' height="'.escape($t['height']).'"';
1938     if (!empty($t['style']))  $html.=' style="'.escape($t['style']).'"';
1939     if (!empty($t['alt']))    $html.=' alt="'.escape($t['alt']).'"';
1940     $html.='></a>';
1941     return $html;
1942 }
1943
1944 // Returns the HTML code to display a thumbnail for a link
1945 // for the picture wall (using lazy image loading)
1946 // Understands various services (youtube.com...)
1947 // Input: $url = URL for which the thumbnail must be found.
1948 //        $href = if provided, this URL will be followed instead of $url
1949 // Returns '' if no thumbnail available.
1950 function lazyThumbnail($url,$href=false)
1951 {
1952     $t = computeThumbnail($url,$href);
1953     if (count($t)==0) return ''; // Empty array = no thumbnail for this URL.
1954
1955     $html='<a href="'.escape($t['href']).'">';
1956
1957     // Lazy image
1958     $html.='<img class="b-lazy" src="#" data-src="'.escape($t['src']).'"';
1959
1960     if (!empty($t['width']))  $html.=' width="'.escape($t['width']).'"';
1961     if (!empty($t['height'])) $html.=' height="'.escape($t['height']).'"';
1962     if (!empty($t['style']))  $html.=' style="'.escape($t['style']).'"';
1963     if (!empty($t['alt']))    $html.=' alt="'.escape($t['alt']).'"';
1964     $html.='>';
1965
1966     // No-JavaScript fallback.
1967     $html.='<noscript><img src="'.escape($t['src']).'"';
1968     if (!empty($t['width']))  $html.=' width="'.escape($t['width']).'"';
1969     if (!empty($t['height'])) $html.=' height="'.escape($t['height']).'"';
1970     if (!empty($t['style']))  $html.=' style="'.escape($t['style']).'"';
1971     if (!empty($t['alt']))    $html.=' alt="'.escape($t['alt']).'"';
1972     $html.='></noscript></a>';
1973
1974     return $html;
1975 }
1976
1977
1978 // -----------------------------------------------------------------------------------------------
1979 // Installation
1980 // This function should NEVER be called if the file data/config.php exists.
1981 function install()
1982 {
1983     // On free.fr host, make sure the /sessions directory exists, otherwise login will not work.
1984     if (endsWith($_SERVER['HTTP_HOST'],'.free.fr') && !is_dir($_SERVER['DOCUMENT_ROOT'].'/sessions')) mkdir($_SERVER['DOCUMENT_ROOT'].'/sessions',0705);
1985
1986
1987     // This part makes sure sessions works correctly.
1988     // (Because on some hosts, session.save_path may not be set correctly,
1989     // or we may not have write access to it.)
1990     if (isset($_GET['test_session']) && ( !isset($_SESSION) || !isset($_SESSION['session_tested']) || $_SESSION['session_tested']!='Working'))
1991     {   // Step 2: Check if data in session is correct.
1992         echo '<pre>Sessions do not seem to work correctly on your server.<br>';
1993         echo 'Make sure the variable session.save_path is set correctly in your php config, and that you have write access to it.<br>';
1994         echo 'It currently points to '.session_save_path().'<br>';
1995         echo 'Check that the hostname used to access Shaarli contains a dot. On some browsers, accessing your server via a hostname like \'localhost\' or any custom hostname without a dot causes cookie storage to fail. We recommend accessing your server via it\'s IP address or Fully Qualified Domain Name.<br>';
1996         echo '<br><a href="?">Click to try again.</a></pre>';
1997         die;
1998     }
1999     if (!isset($_SESSION['session_tested']))
2000     {   // Step 1 : Try to store data in session and reload page.
2001         $_SESSION['session_tested'] = 'Working';  // Try to set a variable in session.
2002         header('Location: '.indexUrl().'?test_session');  // Redirect to check stored data.
2003     }
2004     if (isset($_GET['test_session']))
2005     {   // Step 3: Sessions are OK. Remove test parameter from URL.
2006         header('Location: '.indexUrl());
2007     }
2008
2009
2010     if (!empty($_POST['setlogin']) && !empty($_POST['setpassword']))
2011     {
2012         $tz = 'UTC';
2013         if (!empty($_POST['continent']) && !empty($_POST['city']))
2014             if (isTZvalid($_POST['continent'],$_POST['city']))
2015                 $tz = $_POST['continent'].'/'.$_POST['city'];
2016         $GLOBALS['timezone'] = $tz;
2017         // Everything is ok, let's create config file.
2018         $GLOBALS['login'] = $_POST['setlogin'];
2019         $GLOBALS['salt'] = sha1(uniqid('',true).'_'.mt_rand()); // Salt renders rainbow-tables attacks useless.
2020         $GLOBALS['hash'] = sha1($_POST['setpassword'].$GLOBALS['login'].$GLOBALS['salt']);
2021         $GLOBALS['title'] = (empty($_POST['title']) ? 'Shared links on '.escape(indexUrl()) : $_POST['title'] );
2022         $GLOBALS['config']['ENABLE_UPDATECHECK'] = !empty($_POST['updateCheck']);
2023         writeConfig();
2024         echo '<script>alert("Shaarli is now configured. Please enter your login/password and start shaaring your links!");document.location=\'?do=login\';</script>';
2025         exit;
2026     }
2027
2028     // Display config form:
2029     list($timezone_form,$timezone_js) = templateTZform();
2030     $timezone_html=''; if ($timezone_form!='') $timezone_html='<tr><td><b>Timezone:</b></td><td>'.$timezone_form.'</td></tr>';
2031
2032     $PAGE = new pageBuilder;
2033     $PAGE->assign('timezone_html',$timezone_html);
2034     $PAGE->assign('timezone_js',$timezone_js);
2035     $PAGE->renderPage('install');
2036     exit;
2037 }
2038
2039 // Generates the timezone selection form and JavaScript.
2040 // Input: (optional) current timezone (can be 'UTC/UTC'). It will be pre-selected.
2041 // Output: array(html,js)
2042 // Example: list($htmlform,$js) = templateTZform('Europe/Paris');  // Europe/Paris pre-selected.
2043 // Returns array('','') if server does not support timezones list. (e.g. PHP 5.1 on free.fr)
2044 function templateTZform($ptz=false)
2045 {
2046     if (function_exists('timezone_identifiers_list')) // because of old PHP version (5.1) which can be found on free.fr
2047     {
2048         // Try to split the provided timezone.
2049         if ($ptz==false) { $l=timezone_identifiers_list(); $ptz=$l[0]; }
2050         $spos=strpos($ptz,'/'); $pcontinent=substr($ptz,0,$spos); $pcity=substr($ptz,$spos+1);
2051
2052         // Display config form:
2053         $timezone_form = '';
2054         $timezone_js = '';
2055         // The list is in the form "Europe/Paris", "America/Argentina/Buenos_Aires"...
2056         // We split the list in continents/cities.
2057         $continents = array();
2058         $cities = array();
2059         foreach(timezone_identifiers_list() as $tz)
2060         {
2061             if ($tz=='UTC') $tz='UTC/UTC';
2062             $spos = strpos($tz,'/');
2063             if ($spos!==false)
2064             {
2065                 $continent=substr($tz,0,$spos); $city=substr($tz,$spos+1);
2066                 $continents[$continent]=1;
2067                 if (!isset($cities[$continent])) $cities[$continent]='';
2068                 $cities[$continent].='<option value="'.$city.'"'.($pcity==$city?' selected':'').'>'.$city.'</option>';
2069             }
2070         }
2071         $continents_html = '';
2072         $continents = array_keys($continents);
2073         foreach($continents as $continent)
2074             $continents_html.='<option  value="'.$continent.'"'.($pcontinent==$continent?' selected':'').'>'.$continent.'</option>';
2075         $cities_html = $cities[$pcontinent];
2076         $timezone_form = "Continent: <select name=\"continent\" id=\"continent\" onChange=\"onChangecontinent();\">${continents_html}</select>";
2077         $timezone_form .= "&nbsp;&nbsp;&nbsp;&nbsp;City: <select name=\"city\" id=\"city\">${cities[$pcontinent]}</select><br />";
2078         $timezone_js = "<script>";
2079         $timezone_js .= "function onChangecontinent(){document.getElementById(\"city\").innerHTML = citiescontinent[document.getElementById(\"continent\").value];}";
2080         $timezone_js .= "var citiescontinent = ".json_encode($cities).";" ;
2081         $timezone_js .= "</script>" ;
2082         return array($timezone_form,$timezone_js);
2083     }
2084     return array('','');
2085 }
2086
2087 // Tells if a timezone is valid or not.
2088 // If not valid, returns false.
2089 // If system does not support timezone list, returns false.
2090 function isTZvalid($continent,$city)
2091 {
2092     $tz = $continent.'/'.$city;
2093     if (function_exists('timezone_identifiers_list')) // because of old PHP version (5.1) which can be found on free.fr
2094     {
2095         if (in_array($tz, timezone_identifiers_list())) // it's a valid timezone?
2096                     return true;
2097     }
2098     return false;
2099 }
2100 if (!function_exists('json_encode')) {
2101     function json_encode($data) {
2102         switch ($type = gettype($data)) {
2103             case 'NULL':
2104                 return 'null';
2105             case 'boolean':
2106                 return ($data ? 'true' : 'false');
2107             case 'integer':
2108             case 'double':
2109             case 'float':
2110                 return $data;
2111             case 'string':
2112                 return '"' . addslashes($data) . '"';
2113             case 'object':
2114                 $data = get_object_vars($data);
2115             case 'array':
2116                 $output_index_count = 0;
2117                 $output_indexed = array();
2118                 $output_associative = array();
2119                 foreach ($data as $key => $value) {
2120                     $output_indexed[] = json_encode($value);
2121                     $output_associative[] = json_encode($key) . ':' . json_encode($value);
2122                     if ($output_index_count !== NULL && $output_index_count++ !== $key) {
2123                         $output_index_count = NULL;
2124                     }
2125                 }
2126                 if ($output_index_count !== NULL) {
2127                     return '[' . implode(',', $output_indexed) . ']';
2128                 } else {
2129                     return '{' . implode(',', $output_associative) . '}';
2130                 }
2131             default:
2132                 return ''; // Not supported
2133         }
2134     }
2135 }
2136
2137 // Re-write configuration file according to globals.
2138 // Requires some $GLOBALS to be set (login,hash,salt,title).
2139 // If the config file cannot be saved, an error message is displayed and the user is redirected to "Tools" menu.
2140 // (otherwise, the function simply returns.)
2141 function writeConfig()
2142 {
2143     if (is_file($GLOBALS['config']['CONFIG_FILE']) && !isLoggedIn()) die('You are not authorized to alter config.'); // Only logged in user can alter config.
2144     $config='<?php $GLOBALS[\'login\']='.var_export($GLOBALS['login'],true).'; $GLOBALS[\'hash\']='.var_export($GLOBALS['hash'],true).'; $GLOBALS[\'salt\']='.var_export($GLOBALS['salt'],true).'; ';
2145     $config .='$GLOBALS[\'timezone\']='.var_export($GLOBALS['timezone'],true).'; date_default_timezone_set('.var_export($GLOBALS['timezone'],true).'); $GLOBALS[\'title\']='.var_export($GLOBALS['title'],true).';';
2146     $config .= '$GLOBALS[\'titleLink\']='.var_export($GLOBALS['titleLink'],true).'; ';
2147     $config .= '$GLOBALS[\'redirector\']='.var_export($GLOBALS['redirector'],true).'; ';
2148     $config .= '$GLOBALS[\'disablesessionprotection\']='.var_export($GLOBALS['disablesessionprotection'],true).'; ';
2149     $config .= '$GLOBALS[\'disablejquery\']='.var_export($GLOBALS['disablejquery'],true).'; ';
2150     $config .= '$GLOBALS[\'privateLinkByDefault\']='.var_export($GLOBALS['privateLinkByDefault'],true).'; ';
2151     $config .= '$GLOBALS[\'config\'][\'ENABLE_RSS_PERMALINKS\']='.var_export($GLOBALS['config']['ENABLE_RSS_PERMALINKS'], true).'; ';
2152     $config .= '$GLOBALS[\'config\'][\'ENABLE_UPDATECHECK\']='.var_export($GLOBALS['config']['ENABLE_UPDATECHECK'], true).'; ';
2153     $config .= '$GLOBALS[\'config\'][\'HIDE_PUBLIC_LINKS\']='.var_export($GLOBALS['config']['HIDE_PUBLIC_LINKS'], true).'; ';
2154     $config .= ' ?>';
2155     if (!file_put_contents($GLOBALS['config']['CONFIG_FILE'],$config) || strcmp(file_get_contents($GLOBALS['config']['CONFIG_FILE']),$config)!=0)
2156     {
2157         echo '<script>alert("Shaarli could not create the config file. Please make sure Shaarli has the right to write in the folder is it installed in.");document.location=\'?\';</script>';
2158         exit;
2159     }
2160 }
2161
2162 /* Because some f*cking services like flickr require an extra HTTP request to get the thumbnail URL,
2163    I have deported the thumbnail URL code generation here, otherwise this would slow down page generation.
2164    The following function takes the URL a link (e.g. a flickr page) and return the proper thumbnail.
2165    This function is called by passing the URL:
2166    http://mywebsite.com/shaarli/?do=genthumbnail&hmac=[HMAC]&url=[URL]
2167    [URL] is the URL of the link (e.g. a flickr page)
2168    [HMAC] is the signature for the [URL] (so that these URL cannot be forged).
2169    The function below will fetch the image from the webservice and store it in the cache.
2170 */
2171 function genThumbnail()
2172 {
2173     // Make sure the parameters in the URL were generated by us.
2174     $sign = hash_hmac('sha256', $_GET['url'], $GLOBALS['salt']);
2175     if ($sign!=$_GET['hmac']) die('Naughty boy!');
2176
2177     // Let's see if we don't already have the image for this URL in the cache.
2178     $thumbname=hash('sha1',$_GET['url']).'.jpg';
2179     if (is_file($GLOBALS['config']['CACHEDIR'].'/'.$thumbname))
2180     {   // We have the thumbnail, just serve it:
2181         header('Content-Type: image/jpeg');
2182         echo file_get_contents($GLOBALS['config']['CACHEDIR'].'/'.$thumbname);
2183         return;
2184     }
2185     // We may also serve a blank image (if service did not respond)
2186     $blankname=hash('sha1',$_GET['url']).'.gif';
2187     if (is_file($GLOBALS['config']['CACHEDIR'].'/'.$blankname))
2188     {
2189         header('Content-Type: image/gif');
2190         echo file_get_contents($GLOBALS['config']['CACHEDIR'].'/'.$blankname);
2191         return;
2192     }
2193
2194     // Otherwise, generate the thumbnail.
2195     $url = $_GET['url'];
2196     $domain = parse_url($url,PHP_URL_HOST);
2197
2198     if ($domain=='flickr.com' || endsWith($domain,'.flickr.com'))
2199     {
2200         // Crude replacement to handle new flickr domain policy (They prefer www. now)
2201         $url = str_replace('http://flickr.com/','http://www.flickr.com/',$url);
2202
2203         // Is this a link to an image, or to a flickr page ?
2204         $imageurl='';
2205         if (endswith(parse_url($url,PHP_URL_PATH),'.jpg'))
2206         {  // This is a direct link to an image. e.g. http://farm1.staticflickr.com/5/5921913_ac83ed27bd_o.jpg
2207             preg_match('!(http://farm\d+\.staticflickr\.com/\d+/\d+_\w+_)\w.jpg!',$url,$matches);
2208             if (!empty($matches[1])) $imageurl=$matches[1].'m.jpg';
2209         }
2210         else // This is a flickr page (html)
2211         {
2212             list($httpstatus,$headers,$data) = getHTTP($url,20); // Get the flickr html page.
2213             if (strpos($httpstatus,'200 OK')!==false)
2214             {
2215                 // flickr now nicely provides the URL of the thumbnail in each flickr page.
2216                 preg_match('!<link rel=\"image_src\" href=\"(.+?)\"!',$data,$matches);
2217                 if (!empty($matches[1])) $imageurl=$matches[1];
2218
2219                 // In albums (and some other pages), the link rel="image_src" is not provided,
2220                 // but flickr provides:
2221                 // <meta property="og:image" content="http://farm4.staticflickr.com/3398/3239339068_25d13535ff_z.jpg" />
2222                 if ($imageurl=='')
2223                 {
2224                     preg_match('!<meta property=\"og:image\" content=\"(.+?)\"!',$data,$matches);
2225                     if (!empty($matches[1])) $imageurl=$matches[1];
2226                 }
2227             }
2228         }
2229
2230         if ($imageurl!='')
2231         {   // Let's download the image.
2232             list($httpstatus,$headers,$data) = getHTTP($imageurl,10); // Image is 240x120, so 10 seconds to download should be enough.
2233             if (strpos($httpstatus,'200 OK')!==false)
2234             {
2235                 file_put_contents($GLOBALS['config']['CACHEDIR'].'/'.$thumbname,$data); // Save image to cache.
2236                 header('Content-Type: image/jpeg');
2237                 echo $data;
2238                 return;
2239             }
2240         }
2241     }
2242
2243     elseif ($domain=='vimeo.com' )
2244     {
2245         // This is more complex: we have to perform a HTTP request, then parse the result.
2246         // Maybe we should deport this to JavaScript ? Example: http://stackoverflow.com/questions/1361149/get-img-thumbnails-from-vimeo/4285098#4285098
2247         $vid = substr(parse_url($url,PHP_URL_PATH),1);
2248         list($httpstatus,$headers,$data) = getHTTP('https://vimeo.com/api/v2/video/'.escape($vid).'.php',5);
2249         if (strpos($httpstatus,'200 OK')!==false)
2250         {
2251             $t = unserialize($data);
2252             $imageurl = $t[0]['thumbnail_medium'];
2253             // Then we download the image and serve it to our client.
2254             list($httpstatus,$headers,$data) = getHTTP($imageurl,10);
2255             if (strpos($httpstatus,'200 OK')!==false)
2256             {
2257                 file_put_contents($GLOBALS['config']['CACHEDIR'].'/'.$thumbname,$data); // Save image to cache.
2258                 header('Content-Type: image/jpeg');
2259                 echo $data;
2260                 return;
2261             }
2262         }
2263     }
2264
2265     elseif ($domain=='ted.com' || endsWith($domain,'.ted.com'))
2266     {
2267         // The thumbnail for TED talks is located in the <link rel="image_src" [...]> tag on that page
2268         // http://www.ted.com/talks/mikko_hypponen_fighting_viruses_defending_the_net.html
2269         // <link rel="image_src" href="http://images.ted.com/images/ted/28bced335898ba54d4441809c5b1112ffaf36781_389x292.jpg" />
2270         list($httpstatus,$headers,$data) = getHTTP($url,5);
2271         if (strpos($httpstatus,'200 OK')!==false)
2272         {
2273             // Extract the link to the thumbnail
2274             preg_match('!link rel="image_src" href="(http://images.ted.com/images/ted/.+_\d+x\d+\.jpg)"!',$data,$matches);
2275             if (!empty($matches[1]))
2276             {   // Let's download the image.
2277                 $imageurl=$matches[1];
2278                 list($httpstatus,$headers,$data) = getHTTP($imageurl,20); // No control on image size, so wait long enough.
2279                 if (strpos($httpstatus,'200 OK')!==false)
2280                 {
2281                     $filepath=$GLOBALS['config']['CACHEDIR'].'/'.$thumbname;
2282                     file_put_contents($filepath,$data); // Save image to cache.
2283                     if (resizeImage($filepath))
2284                     {
2285                         header('Content-Type: image/jpeg');
2286                         echo file_get_contents($filepath);
2287                         return;
2288                     }
2289                 }
2290             }
2291         }
2292     }
2293
2294     elseif ($domain=='xkcd.com' || endsWith($domain,'.xkcd.com'))
2295     {
2296         // There is no thumbnail available for xkcd comics, so download the whole image and resize it.
2297         // http://xkcd.com/327/
2298         // <img src="http://imgs.xkcd.com/comics/exploits_of_a_mom.png" title="<BLABLA>" alt="<BLABLA>" />
2299         list($httpstatus,$headers,$data) = getHTTP($url,5);
2300         if (strpos($httpstatus,'200 OK')!==false)
2301         {
2302             // Extract the link to the thumbnail
2303             preg_match('!<img src="(http://imgs.xkcd.com/comics/.*)" title="[^s]!',$data,$matches);
2304             if (!empty($matches[1]))
2305             {   // Let's download the image.
2306                 $imageurl=$matches[1];
2307                 list($httpstatus,$headers,$data) = getHTTP($imageurl,20); // No control on image size, so wait long enough.
2308                 if (strpos($httpstatus,'200 OK')!==false)
2309                 {
2310                     $filepath=$GLOBALS['config']['CACHEDIR'].'/'.$thumbname;
2311                     file_put_contents($filepath,$data); // Save image to cache.
2312                     if (resizeImage($filepath))
2313                     {
2314                         header('Content-Type: image/jpeg');
2315                         echo file_get_contents($filepath);
2316                         return;
2317                     }
2318                 }
2319             }
2320         }
2321     }
2322
2323     else
2324     {
2325         // For all other domains, we try to download the image and make a thumbnail.
2326         list($httpstatus,$headers,$data) = getHTTP($url,30);  // We allow 30 seconds max to download (and downloads are limited to 4 Mb)
2327         if (strpos($httpstatus,'200 OK')!==false)
2328         {
2329             $filepath=$GLOBALS['config']['CACHEDIR'].'/'.$thumbname;
2330             file_put_contents($filepath,$data); // Save image to cache.
2331             if (resizeImage($filepath))
2332             {
2333                 header('Content-Type: image/jpeg');
2334                 echo file_get_contents($filepath);
2335                 return;
2336             }
2337         }
2338     }
2339
2340
2341     // Otherwise, return an empty image (8x8 transparent gif)
2342     $blankgif = base64_decode('R0lGODlhCAAIAIAAAP///////yH5BAEKAAEALAAAAAAIAAgAAAIHjI+py+1dAAA7');
2343     file_put_contents($GLOBALS['config']['CACHEDIR'].'/'.$blankname,$blankgif); // Also put something in cache so that this URL is not requested twice.
2344     header('Content-Type: image/gif');
2345     echo $blankgif;
2346 }
2347
2348 // Make a thumbnail of the image (to width: 120 pixels)
2349 // Returns true if success, false otherwise.
2350 function resizeImage($filepath)
2351 {
2352     if (!function_exists('imagecreatefromjpeg')) return false; // GD not present: no thumbnail possible.
2353
2354     // Trick: some stupid people rename GIF as JPEG... or else.
2355     // So we really try to open each image type whatever the extension is.
2356     $header=file_get_contents($filepath,false,NULL,0,256); // Read first 256 bytes and try to sniff file type.
2357     $im=false;
2358     $i=strpos($header,'GIF8'); if (($i!==false) && ($i==0)) $im = imagecreatefromgif($filepath); // Well this is crude, but it should be enough.
2359     $i=strpos($header,'PNG'); if (($i!==false) && ($i==1)) $im = imagecreatefrompng($filepath);
2360     $i=strpos($header,'JFIF'); if ($i!==false) $im = imagecreatefromjpeg($filepath);
2361     if (!$im) return false;  // Unable to open image (corrupted or not an image)
2362     $w = imagesx($im);
2363     $h = imagesy($im);
2364     $ystart = 0; $yheight=$h;
2365     if ($h>$w) { $ystart= ($h/2)-($w/2); $yheight=$w/2; }
2366     $nw = 120;   // Desired width
2367     $nh = min(floor(($h*$nw)/$w),120); // Compute new width/height, but maximum 120 pixels height.
2368     // Resize image:
2369     $im2 = imagecreatetruecolor($nw,$nh);
2370     imagecopyresampled($im2, $im, 0, 0, 0, $ystart, $nw, $nh, $w, $yheight);
2371     imageinterlace($im2,true); // For progressive JPEG.
2372     $tempname=$filepath.'_TEMP.jpg';
2373     imagejpeg($im2, $tempname, 90);
2374     imagedestroy($im);
2375     imagedestroy($im2);
2376     unlink($filepath);
2377     rename($tempname,$filepath);  // Overwrite original picture with thumbnail.
2378     return true;
2379 }
2380
2381 // Invalidate caches when the database is changed or the user logs out.
2382 // (e.g. tags cache).
2383 function invalidateCaches()
2384 {
2385     unset($_SESSION['tags']);  // Purge cache attached to session.
2386     pageCache::purgeCache();   // Purge page cache shared by sessions.
2387 }
2388
2389 if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=genthumbnail')) { genThumbnail(); exit; }  // Thumbnail generation/cache does not need the link database.
2390 if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=rss')) { showRSS(); exit; }
2391 if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=atom')) { showATOM(); exit; }
2392 if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=dailyrss')) { showDailyRSS(); exit; }
2393 if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=daily')) { showDaily(); exit; }
2394 if (!isset($_SESSION['LINKS_PER_PAGE'])) $_SESSION['LINKS_PER_PAGE']=$GLOBALS['config']['LINKS_PER_PAGE'];
2395 renderPage();
2396 ?>