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