index.php

   1 <?php
   2 // Shaarli 0.0.40 beta - 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 // Hardcoded parameter (These parameters can be overwritten by creating the file /config/options.php)
   9 $GLOBALS['config']['DATADIR'] = 'data'; // Data subdirectory
  10 $GLOBALS['config']['CONFIG_FILE'] = $GLOBALS['config']['DATADIR'].'/config.php'; // Configuration file (user login/password)
  11 $GLOBALS['config']['DATASTORE'] = $GLOBALS['config']['DATADIR'].'/datastore.php'; // Data storage file.
  12 $GLOBALS['config']['LINKS_PER_PAGE'] = 20; // Default links per page.
  13 $GLOBALS['config']['IPBANS_FILENAME'] = $GLOBALS['config']['DATADIR'].'/ipbans.php'; // File storage for failures and bans.
  14 $GLOBALS['config']['BAN_AFTER'] = 4;        // Ban IP after this many failures.
  15 $GLOBALS['config']['BAN_DURATION'] = 1800;  // Ban duration for IP address after login failures (in seconds) (1800 sec. = 30 minutes)
  16 $GLOBALS['config']['OPEN_SHAARLI'] = false; // If true, anyone can add/edit/delete links without having to login
  17 $GLOBALS['config']['HIDE_TIMESTAMPS'] = false; // If true, the moment when links were saved are not shown to users that are not logged in.
  18 $GLOBALS['config']['ENABLE_THUMBNAILS'] = true; // Enable thumbnails in links.
  19 $GLOBALS['config']['CACHEDIR'] = 'cache'; // Cache directory for thumbnails for SLOW services (like flickr)
  20 $GLOBALS['config']['PAGECACHE'] = 'pagecache'; // Page cache directory.
  21 $GLOBALS['config']['ENABLE_LOCALCACHE'] = true; // Enable Shaarli to store thumbnail in a local cache. Disable to reduce webspace usage.
  22 $GLOBALS['config']['PUBSUBHUB_URL'] = ''; // PubSubHubbub support. Put an empty string to disable, or put your hub url here to enable.
  23 $GLOBALS['config']['UPDATECHECK_FILENAME'] = $GLOBALS['config']['DATADIR'].'/lastupdatecheck.txt'; // For updates check of Shaarli.
  24 $GLOBALS['config']['UPDATECHECK_INTERVAL'] = 86400 ; // Updates check frequency for Shaarli. 86400 seconds=24 hours
  25                                           // Note: You must have publisher.php in the same directory as Shaarli index.php
  26 // -----------------------------------------------------------------------------------------------
  27 // You should not touch below (or at your own risks !)
  28 // Optionnal config file.
  29 if (is_file($GLOBALS['config']['DATADIR'].'/options.php')) require($GLOBALS['config']['DATADIR'].'/options.php');
  30
  31 define('shaarli_version','0.0.40 beta');
  32 define('PHPPREFIX','<?php /* '); // Prefix to encapsulate data in php code.
  33 define('PHPSUFFIX',' */ ?>'); // Suffix to encapsulate data in php code.
  34
  35 // Force cookie path (but do not change lifetime)
  36 $cookie=session_get_cookie_params();
  37 $cookiedir = ''; if(dirname($_SERVER['SCRIPT_NAME'])!='/') $cookiedir=dirname($_SERVER["SCRIPT_NAME"]).'/';
  38 session_set_cookie_params($cookie['lifetime'],$cookiedir); // Set default cookie expiration and path.
  39
  40 // Set session parameters on server side.
  41 define('INACTIVITY_TIMEOUT',3600); // (in seconds). If the user does not access any page within this time, his/her session is considered expired.
  42 ini_set('session.use_cookies', 1);       // Use cookies to store session.
  43 ini_set('session.use_only_cookies', 1);  // Force cookies for session (phpsessionID forbidden in URL)
  44 ini_set('session.use_trans_sid', false); // Prevent php to use sessionID in URL if cookies are disabled.
  45 session_name('shaarli');
  46 if (session_id() == '') session_start();  // Start session if needed (Some server auto-start sessions).
  47
  48 // PHP Settings
  49 ini_set('max_input_time','60');  // High execution time in case of problematic imports/exports.
  50 ini_set('memory_limit', '128M');  // Try to set max upload file size and read (May not work on some hosts).
  51 ini_set('post_max_size', '16M');
  52 ini_set('upload_max_filesize', '16M');
  53 checkphpversion();
  54 error_reporting(E_ALL^E_WARNING);  // See all error except warnings.
  55 //error_reporting(-1); // See all errors (for debugging only)
  56
  57 include "inc/rain.tpl.class.php"; //include Rain TPL
  58 raintpl::$tpl_dir = "tpl/"; // template directory
  59 if (!is_dir('tmp')) { mkdir('tmp',0705); chmod('tmp',0705); }
  60 raintpl::$cache_dir = "tmp/"; // cache directory
  61
  62 ob_start();  // Output buffering for the page cache.
  63
  64
  65 // In case stupid admin has left magic_quotes enabled in php.ini:
  66 if (get_magic_quotes_gpc())
  67 {
  68     function stripslashes_deep($value) { $value = is_array($value) ? array_map('stripslashes_deep', $value) : stripslashes($value); return $value; }
  69     $_POST = array_map('stripslashes_deep', $_POST);
  70     $_GET = array_map('stripslashes_deep', $_GET);
  71     $_COOKIE = array_map('stripslashes_deep', $_COOKIE);
  72 }
  73
  74 // Prevent caching on client side or proxy: (yes, it's ugly)
  75 header("Last-Modified: " . gmdate("D, d M Y H:i:s") . " GMT");
  76 header("Cache-Control: no-store, no-cache, must-revalidate");
  77 header("Cache-Control: post-check=0, pre-check=0", false);
  78 header("Pragma: no-cache");
  79
  80 // Directories creations (Note that your web host may require differents rights than 705.)
  81 if (!is_dir($GLOBALS['config']['DATADIR'])) { mkdir($GLOBALS['config']['DATADIR'],0705); chmod($GLOBALS['config']['DATADIR'],0705); }
  82 if (!is_dir('tmp')) { mkdir('tmp',0705); chmod('tmp',0705); } // For RainTPL temporary files.
  83 if (!is_file($GLOBALS['config']['DATADIR'].'/.htaccess')) { file_put_contents($GLOBALS['config']['DATADIR'].'/.htaccess',"Allow from none\nDeny from all\n"); } // Protect data files.
  84 if ($GLOBALS['config']['ENABLE_LOCALCACHE'])
  85 {
  86     if (!is_dir($GLOBALS['config']['CACHEDIR'])) { mkdir($GLOBALS['config']['CACHEDIR'],0705); chmod($GLOBALS['config']['CACHEDIR'],0705); }
  87     if (!is_file($GLOBALS['config']['CACHEDIR'].'/.htaccess')) { file_put_contents($GLOBALS['config']['CACHEDIR'].'/.htaccess',"Allow from none\nDeny from all\n"); } // Protect data files.
  88 }
  89
  90 // Run config screen if first run:
  91 if (!is_file($GLOBALS['config']['CONFIG_FILE'])) install();
  92
  93 require $GLOBALS['config']['CONFIG_FILE'];  // Read login/password hash into $GLOBALS.
  94
  95 // Handling of old config file which do not have the new parameters.
  96 if (empty($GLOBALS['title'])) $GLOBALS['title']='Shared links on '.htmlspecialchars(indexUrl());
  97 if (empty($GLOBALS['timezone'])) $GLOBALS['timezone']=date_default_timezone_get();
  98 if (empty($GLOBALS['disablesessionprotection'])) $GLOBALS['disablesessionprotection']=false;
  99
 100 autoLocale(); // Sniff browser language and set date format accordingly.
 101 header('Content-Type: text/html; charset=utf-8'); // We use UTF-8 for proper international characters handling.
 102
 103 // Check php version
 104 function checkphpversion()
 105 {
 106     if (version_compare(PHP_VERSION, '5.1.0') < 0)
 107     {
 108         header('Content-Type: text/plain; charset=utf-8');
 109         echo 'Your server supports php '.PHP_VERSION.'. Shaarli requires at least php 5.1.0, and thus cannot run. Sorry.';
 110         exit;
 111     }
 112 }
 113
 114 // Checks if an update is available for Shaarli.
 115 // (at most once a day, and only for registered user.)
 116 // Output: '' = no new version.
 117 //         other= the available version.
 118 function checkUpdate()
 119 {
 120     if (!isLoggedIn()) return ''; // Do not check versions for visitors.
 121
 122     // Get latest version number at most once a day.
 123     if (!is_file($GLOBALS['config']['UPDATECHECK_FILENAME']) || (filemtime($GLOBALS['config']['UPDATECHECK_FILENAME'])<time()-($GLOBALS['config']['UPDATECHECK_INTERVAL'])))
 124     {
 125         $version=shaarli_version;
 126         list($httpstatus,$headers,$data) = getHTTP('http://sebsauvage.net/files/shaarli_version.txt',2);
 127         if (strpos($httpstatus,'200 OK')!==false) $version=$data;
 128         // If failed, nevermind. We don't want to bother the user with that.
 129         file_put_contents($GLOBALS['config']['UPDATECHECK_FILENAME'],$version); // touch file date
 130     }
 131     // Compare versions:
 132     $newestversion=file_get_contents($GLOBALS['config']['UPDATECHECK_FILENAME']);
 133     if (version_compare($newestversion,shaarli_version)==1) return $newestversion;
 134     return '';
 135 }
 136
 137
 138 // -----------------------------------------------------------------------------------------------
 139 // Simple cache system (mainly for the RSS/ATOM feeds).
 140
 141 class pageCache
 142 {
 143     private $url; // Full URL of the page to cache (typically the value returned by pageUrl())
 144     private $shouldBeCached; // boolean: Should this url be cached ?
 145     private $filename; // Name of the cache file for this url
 146
 147     /*
 148          $url = url (typically the value returned by pageUrl())
 149          $shouldBeCached = boolean. If false, the cache will be disabled.
 150     */
 151     public function __construct($url,$shouldBeCached)
 152     {
 153         $this->url = $url;
 154         $this->filename = $GLOBALS['config']['PAGECACHE'].'/'.sha1($url).'.cache';
 155         $this->shouldBeCached = $shouldBeCached;
 156     }
 157
 158     // If the page should be cached and a cached version exists,
 159     // returns the cached version (otherwise, return null).
 160     public function cachedVersion()
 161     {
 162         if (!$this->shouldBeCached) return null;
 163         if (is_file($this->filename)) { return file_get_contents($this->filename); exit; }
 164         return null;
 165     }
 166
 167     // Put a page in the cache.
 168     public function cache($page)
 169     {
 170         if (!$this->shouldBeCached) return;
 171         if (!is_dir($GLOBALS['config']['PAGECACHE'])) { mkdir($GLOBALS['config']['PAGECACHE'],0705); chmod($GLOBALS['config']['PAGECACHE'],0705); }
 172         file_put_contents($this->filename,$page);
 173     }
 174
 175     // Purge the whole cache.
 176     // (call with pageCache::purgeCache())
 177     public static function purgeCache()
 178     {
 179         if (is_dir($GLOBALS['config']['PAGECACHE']))
 180         {
 181             $handler = opendir($GLOBALS['config']['PAGECACHE']);
 182             if ($handler!==false)
 183             {
 184                 while (($filename = readdir($handler))!==false)
 185                 {
 186                     if (endsWith($filename,'.cache')) { unlink($GLOBALS['config']['PAGECACHE'].'/'.$filename); }
 187                 }
 188                 closedir($handler);
 189             }
 190         }
 191     }
 192
 193 }
 194
 195
 196 // -----------------------------------------------------------------------------------------------
 197 // Log to text file
 198 function logm($message)
 199 {
 200     $t = strval(date('Y/m/d_H:i:s')).' - '.$_SERVER["REMOTE_ADDR"].' - '.strval($message)."\n";
 201     file_put_contents($GLOBALS['config']['DATADIR'].'/log.txt',$t,FILE_APPEND);
 202 }
 203
 204 // Same as nl2br(), but escapes < and >
 205 function nl2br_escaped($html)
 206 {
 207     return str_replace('>','&gt;',str_replace('<','&lt;',nl2br($html)));
 208 }
 209
 210 /* Returns the small hash of a string
 211    eg. smallHash('20111006_131924') --> yZH23w
 212    Small hashes:
 213      - are unique (well, as unique as crc32, at last)
 214      - are always 6 characters long.
 215      - only use the following characters: a-z A-Z 0-9 - _ @
 216      - are NOT cryptographically secure (they CAN be forged)
 217    In Shaarli, they are used as a tinyurl-like link to individual entries.
 218 */
 219 function smallHash($text)
 220 {
 221     $t = rtrim(base64_encode(hash('crc32',$text,true)),'=');
 222     $t = str_replace('+','-',$t); // Get rid of characters which need encoding in URLs.
 223     $t = str_replace('/','_',$t);
 224     $t = str_replace('=','@',$t);
 225     return $t;
 226 }
 227
 228 // In a string, converts urls to clickable links.
 229 // Function inspired from http://www.php.net/manual/en/function.preg-replace.php#85722
 230 function text2clickable($url)
 231 {
 232     $redir = empty($GLOBALS['redirector']) ? '' : $GLOBALS['redirector'];
 233     return preg_replace('!(((?:https?|ftp|file)://|apt:|magnet:)\S+[[:alnum:]]/?)!si','<a href="'.$redir.'$1" rel="nofollow">$1</a>',$url);
 234 }
 235
 236 // This function inserts &nbsp; where relevant so that multiple spaces are properly displayed in HTML
 237 // even in the absence of <pre>  (This is used in description to keep text formatting)
 238 function keepMultipleSpaces($text)
 239 {
 240     return str_replace('  ',' &nbsp;',$text);
 241
 242 }
 243 // ------------------------------------------------------------------------------------------
 244 // Sniff browser language to display dates in the right format automatically.
 245 // (Note that is may not work on your server if the corresponding local is not installed.)
 246 function autoLocale()
 247 {
 248     $loc='en_US'; // Default if browser does not send HTTP_ACCEPT_LANGUAGE
 249     if (isset($_SERVER['HTTP_ACCEPT_LANGUAGE'])) // eg. "fr,fr-fr;q=0.8,en;q=0.5,en-us;q=0.3"
 250     {   // (It's a bit crude, but it works very well. Prefered language is always presented first.)
 251         if (preg_match('/([a-z]{2}(-[a-z]{2})?)/i',$_SERVER['HTTP_ACCEPT_LANGUAGE'],$matches)) $loc=$matches[1];
 252     }
 253     setlocale(LC_TIME,$loc);  // LC_TIME = Set local for date/time format only.
 254 }
 255
 256 // ------------------------------------------------------------------------------------------
 257 // PubSubHubbub protocol support (if enabled)  [UNTESTED]
 258 // (Source: http://aldarone.fr/les-flux-rss-shaarli-et-pubsubhubbub/ )
 259 if (!empty($GLOBALS['config']['PUBSUBHUB_URL'])) include './publisher.php';
 260 function pubsubhub()
 261 {
 262     if (!empty($GLOBALS['config']['PUBSUBHUB_URL']))
 263     {
 264        $p = new Publisher($GLOBALS['config']['PUBSUBHUB_URL']);
 265        $topic_url = array (
 266                        indexUrl().'?do=atom',
 267                        indexUrl().'?do=rss'
 268                     );
 269        $p->publish_update($topic_url);
 270     }
 271 }
 272
 273 // ------------------------------------------------------------------------------------------
 274 // Session management
 275
 276 // Returns the IP address of the client (Used to prevent session cookie hijacking.)
 277 function allIPs()
 278 {
 279     $ip = $_SERVER["REMOTE_ADDR"];
 280     // Then we use more HTTP headers to prevent session hijacking from users behind the same proxy.
 281     if (isset($_SERVER['HTTP_X_FORWARDED_FOR'])) { $ip=$ip.'_'.$_SERVER['HTTP_X_FORWARDED_FOR']; }
 282     if (isset($_SERVER['HTTP_CLIENT_IP'])) { $ip=$ip.'_'.$_SERVER['HTTP_CLIENT_IP']; }
 283     return $ip;
 284 }
 285
 286 // Check that user/password is correct.
 287 function check_auth($login,$password)
 288 {
 289     $hash = sha1($password.$login.$GLOBALS['salt']);
 290     if ($login==$GLOBALS['login'] && $hash==$GLOBALS['hash'])
 291     {   // Login/password is correct.
 292         $_SESSION['uid'] = sha1(uniqid('',true).'_'.mt_rand()); // generate unique random number (different than phpsessionid)
 293         $_SESSION['ip']=allIPs();                // We store IP address(es) of the client to make sure session is not hijacked.
 294         $_SESSION['username']=$login;
 295         $_SESSION['expires_on']=time()+INACTIVITY_TIMEOUT;  // Set session expiration.
 296         logm('Login successful');
 297         return True;
 298     }
 299     logm('Login failed for user '.$login);
 300     return False;
 301 }
 302
 303 // Returns true if the user is logged in.
 304 function isLoggedIn()
 305 {
 306     if ($GLOBALS['config']['OPEN_SHAARLI']) return true;
 307
 308     if (!isset($GLOBALS['login'])) return false;  // Shaarli is not configured yet.
 309
 310     // If session does not exist on server side, or IP address has changed, or session has expired, logout.
 311     if (empty($_SESSION['uid']) || ($GLOBALS['disablesessionprotection']==false && $_SESSION['ip']!=allIPs()) || time()>=$_SESSION['expires_on'])
 312     {
 313         logout();
 314         return false;
 315     }
 316     if (!empty($_SESSION['longlastingsession']))  $_SESSION['expires_on']=time()+$_SESSION['longlastingsession']; // In case of "Stay signed in" checked.
 317     else $_SESSION['expires_on']=time()+INACTIVITY_TIMEOUT; // Standard session expiration date.
 318
 319     return true;
 320 }
 321
 322 // Force logout.
 323 function logout() { if (isset($_SESSION)) { unset($_SESSION['uid']); unset($_SESSION['ip']); unset($_SESSION['username']); unset($_SESSION['privateonly']); }  }
 324
 325
 326 // ------------------------------------------------------------------------------------------
 327 // Brute force protection system
 328 // Several consecutive failed logins will ban the IP address for 30 minutes.
 329 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?>");
 330 include $GLOBALS['config']['IPBANS_FILENAME'];
 331 // Signal a failed login. Will ban the IP if too many failures:
 332 function ban_loginFailed()
 333 {
 334     $ip=$_SERVER["REMOTE_ADDR"]; $gb=$GLOBALS['IPBANS'];
 335     if (!isset($gb['FAILURES'][$ip])) $gb['FAILURES'][$ip]=0;
 336     $gb['FAILURES'][$ip]++;
 337     if ($gb['FAILURES'][$ip]>($GLOBALS['config']['BAN_AFTER']-1))
 338     {
 339         $gb['BANS'][$ip]=time()+$GLOBALS['config']['BAN_DURATION'];
 340         logm('IP address banned from login');
 341     }
 342     $GLOBALS['IPBANS'] = $gb;
 343     file_put_contents($GLOBALS['config']['IPBANS_FILENAME'], "<?php\n\$GLOBALS['IPBANS']=".var_export($gb,true).";\n?>");
 344 }
 345
 346 // Signals a successful login. Resets failed login counter.
 347 function ban_loginOk()
 348 {
 349     $ip=$_SERVER["REMOTE_ADDR"]; $gb=$GLOBALS['IPBANS'];
 350     unset($gb['FAILURES'][$ip]); unset($gb['BANS'][$ip]);
 351     $GLOBALS['IPBANS'] = $gb;
 352     file_put_contents($GLOBALS['config']['IPBANS_FILENAME'], "<?php\n\$GLOBALS['IPBANS']=".var_export($gb,true).";\n?>");
 353 }
 354
 355 // Checks if the user CAN login. If 'true', the user can try to login.
 356 function ban_canLogin()
 357 {
 358     $ip=$_SERVER["REMOTE_ADDR"]; $gb=$GLOBALS['IPBANS'];
 359     if (isset($gb['BANS'][$ip]))
 360     {
 361         // User is banned. Check if the ban has expired:
 362         if ($gb['BANS'][$ip]<=time())
 363         {   // Ban expired, user can try to login again.
 364             logm('Ban lifted.');
 365             unset($gb['FAILURES'][$ip]); unset($gb['BANS'][$ip]);
 366             file_put_contents($GLOBALS['config']['IPBANS_FILENAME'], "<?php\n\$GLOBALS['IPBANS']=".var_export($gb,true).";\n?>");
 367             return true; // Ban has expired, user can login.
 368         }
 369         return false; // User is banned.
 370     }
 371     return true; // User is not banned.
 372 }
 373
 374 // ------------------------------------------------------------------------------------------
 375 // Process login form: Check if login/password is correct.
 376 if (isset($_POST['login']))
 377 {
 378     if (!ban_canLogin()) die('I said: NO. You are banned for the moment. Go away.');
 379     if (isset($_POST['password']) && tokenOk($_POST['token']) && (check_auth($_POST['login'], $_POST['password'])))
 380     {   // Login/password is ok.
 381         ban_loginOk();
 382         // If user wants to keep the session cookie even after the browser closes:
 383         if (!empty($_POST['longlastingsession']))
 384         {
 385             $_SESSION['longlastingsession']=31536000;  // (31536000 seconds = 1 year)
 386             $_SESSION['expires_on']=time()+$_SESSION['longlastingsession'];  // Set session expiration on server-side.
 387
 388             $cookiedir = ''; if(dirname($_SERVER['SCRIPT_NAME'])!='/') $cookiedir=dirname($_SERVER["SCRIPT_NAME"]).'/';
 389             session_set_cookie_params($_SESSION['longlastingsession'],$cookiedir); // Set session cookie expiration on client side
 390             // Note: Never forget the trailing slash on the cookie path !
 391             session_regenerate_id(true);  // Send cookie with new expiration date to browser.
 392         }
 393         else // Standard session expiration (=when browser closes)
 394         {
 395             $cookiedir = ''; if(dirname($_SERVER['SCRIPT_NAME'])!='/') $cookiedir=dirname($_SERVER["SCRIPT_NAME"]).'/';
 396             session_set_cookie_params(0,$cookiedir); // 0 means "When browser closes"
 397             session_regenerate_id(true);
 398         }
 399         // Optional redirect after login:
 400         if (isset($_GET['post'])) { header('Location: ?post='.urlencode($_GET['post']).(!empty($_GET['title'])?'&title='.urlencode($_GET['title']):'').(!empty($_GET['source'])?'&source='.urlencode($_GET['source']):'')); exit; }
 401         if (isset($_POST['returnurl']))
 402         {
 403             if (endsWith($_POST['returnurl'],'?do=login')) { header('Location: ?'); exit; } // Prevent loops over login screen.
 404             header('Location: '.$_POST['returnurl']); exit;
 405         }
 406         header('Location: ?'); exit;
 407     }
 408     else
 409     {
 410         ban_loginFailed();
 411         echo '<script language="JavaScript">alert("Wrong login/password.");document.location=\'?do=login\';</script>'; // Redirect to login screen.
 412         exit;
 413     }
 414 }
 415
 416 // ------------------------------------------------------------------------------------------
 417 // Misc utility functions:
 418
 419 // Returns the server URL (including port and http/https), without path.
 420 // eg. "http://myserver.com:8080"
 421 // You can append $_SERVER['SCRIPT_NAME'] to get the current script URL.
 422 function serverUrl()
 423 {
 424     $https = (!empty($_SERVER['HTTPS']) && (strtolower($_SERVER['HTTPS'])=='on')) || $_SERVER["SERVER_PORT"]=='443'; // HTTPS detection.
 425     $serverport = ($_SERVER["SERVER_PORT"]=='80' || ($https && $_SERVER["SERVER_PORT"]=='443') ? '' : ':'.$_SERVER["SERVER_PORT"]);
 426     return 'http'.($https?'s':'').'://'.$_SERVER["SERVER_NAME"].$serverport;
 427 }
 428
 429 // Returns the absolute URL of current script, without the query.
 430 // (eg. http://sebsauvage.net/links/)
 431 function indexUrl()
 432 {
 433     $scriptname = $_SERVER["SCRIPT_NAME"];
 434     // If the script is named 'index.php', we remove it (for better looking URLs,
 435     // eg. http://mysite.com/shaarli/?abcde instead of http://mysite.com/shaarli/index.php?abcde)
 436     if (endswith($scriptname,'index.php')) $scriptname = substr($scriptname,0,strlen($scriptname)-9);
 437     return serverUrl() . $scriptname;
 438 }
 439
 440 // Returns the absolute URL of current script, WITH the query.
 441 // (eg. http://sebsauvage.net/links/?toto=titi&spamspamspam=humbug)
 442 function pageUrl()
 443 {
 444     return indexUrl().(!empty($_SERVER["QUERY_STRING"]) ? '?'.$_SERVER["QUERY_STRING"] : '');
 445 }
 446
 447 // Convert post_max_size/upload_max_filesize (eg.'16M') parameters to bytes.
 448 function return_bytes($val)
 449 {
 450     $val = trim($val); $last=strtolower($val[strlen($val)-1]);
 451     switch($last)
 452     {
 453         case 'g': $val *= 1024;
 454         case 'm': $val *= 1024;
 455         case 'k': $val *= 1024;
 456     }
 457     return $val;
 458 }
 459
 460 // Try to determine max file size for uploads (POST).
 461 // Returns an integer (in bytes)
 462 function getMaxFileSize()
 463 {
 464     $size1 = return_bytes(ini_get('post_max_size'));
 465     $size2 = return_bytes(ini_get('upload_max_filesize'));
 466     // Return the smaller of two:
 467     $maxsize = min($size1,$size2);
 468     // FIXME: Then convert back to readable notations ? (eg. 2M instead of 2000000)
 469     return $maxsize;
 470 }
 471
 472 // Tells if a string start with a substring or not.
 473 function startsWith($haystack,$needle,$case=true)
 474 {
 475     if($case){return (strcmp(substr($haystack, 0, strlen($needle)),$needle)===0);}
 476     return (strcasecmp(substr($haystack, 0, strlen($needle)),$needle)===0);
 477 }
 478
 479 // Tells if a string ends with a substring or not.
 480 function endsWith($haystack,$needle,$case=true)
 481 {
 482     if($case){return (strcmp(substr($haystack, strlen($haystack) - strlen($needle)),$needle)===0);}
 483     return (strcasecmp(substr($haystack, strlen($haystack) - strlen($needle)),$needle)===0);
 484 }
 485
 486 /*  Converts a linkdate time (YYYYMMDD_HHMMSS) of an article to a timestamp (Unix epoch)
 487     (used to build the ADD_DATE attribute in Netscape-bookmarks file)
 488     PS: I could have used strptime(), but it does not exist on Windows. I'm too kind. */
 489 function linkdate2timestamp($linkdate)
 490 {
 491     $Y=$M=$D=$h=$m=$s=0;
 492     $r = sscanf($linkdate,'%4d%2d%2d_%2d%2d%2d',$Y,$M,$D,$h,$m,$s);
 493     return mktime($h,$m,$s,$M,$D,$Y);
 494 }
 495
 496 /*  Converts a linkdate time (YYYYMMDD_HHMMSS) of an article to a RFC822 date.
 497     (used to build the pubDate attribute in RSS feed.)  */
 498 function linkdate2rfc822($linkdate)
 499 {
 500     return date('r',linkdate2timestamp($linkdate)); // 'r' is for RFC822 date format.
 501 }
 502
 503 /*  Converts a linkdate time (YYYYMMDD_HHMMSS) of an article to a ISO 8601 date.
 504     (used to build the updated tags in ATOM feed.)  */
 505 function linkdate2iso8601($linkdate)
 506 {
 507     return date('c',linkdate2timestamp($linkdate)); // 'c' is for ISO 8601 date format.
 508 }
 509
 510 /*  Converts a linkdate time (YYYYMMDD_HHMMSS) of an article to a localized date format.
 511     (used to display link date on screen)
 512     The date format is automatically chosen according to locale/languages sniffed from browser headers (see autoLocale()). */
 513 function linkdate2locale($linkdate)
 514 {
 515     return utf8_encode(strftime('%c',linkdate2timestamp($linkdate))); // %c is for automatic date format according to locale.
 516     // Note that if you use a local which is not installed on your webserver,
 517     // the date will not be displayed in the chosen locale, but probably in US notation.
 518 }
 519
 520 // Parse HTTP response headers and return an associative array.
 521 function http_parse_headers_shaarli( $headers )
 522 {
 523     $res=array();
 524     foreach($headers as $header)
 525     {
 526         $i = strpos($header,': ');
 527         if ($i!==false)
 528         {
 529             $key=substr($header,0,$i);
 530             $value=substr($header,$i+2,strlen($header)-$i-2);
 531             $res[$key]=$value;
 532         }
 533     }
 534     return $res;
 535 }
 536
 537 /* GET an URL.
 538    Input: $url : url to get (http://...)
 539           $timeout : Network timeout (will wait this many seconds for an anwser before giving up).
 540    Output: An array.  [0] = HTTP status message (eg. "HTTP/1.1 200 OK") or error message
 541                       [1] = associative array containing HTTP response headers (eg. echo getHTTP($url)[1]['Content-Type'])
 542                       [2] = data
 543     Example: list($httpstatus,$headers,$data) = getHTTP('http://sebauvage.net/');
 544              if (strpos($httpstatus,'200 OK')!==false)
 545                  echo 'Data type: '.htmlspecialchars($headers['Content-Type']);
 546              else
 547                  echo 'There was an error: '.htmlspecialchars($httpstatus)
 548 */
 549 function getHTTP($url,$timeout=30)
 550 {
 551     try
 552     {
 553         $options = array('http'=>array('method'=>'GET','timeout' => $timeout)); // Force network timeout
 554         $context = stream_context_create($options);
 555         $data=file_get_contents($url,false,$context,-1, 4000000); // We download at most 4 Mb from source.
 556         if (!$data) { return array('HTTP Error',array(),''); }
 557         $httpStatus=$http_response_header[0]; // eg. "HTTP/1.1 200 OK"
 558         $responseHeaders=http_parse_headers_shaarli($http_response_header);
 559         return array($httpStatus,$responseHeaders,$data);
 560     }
 561     catch (Exception $e)  // getHTTP *can* fail silentely (we don't care if the title cannot be fetched)
 562     {
 563         return array($e->getMessage(),'','');
 564     }
 565 }
 566
 567 // Extract title from an HTML document.
 568 // (Returns an empty string if not found.)
 569 function html_extract_title($html)
 570 {
 571   return preg_match('!<title>(.*?)</title>!is', $html, $matches) ? trim(str_replace("\n",' ', $matches[1])) : '' ;
 572 }
 573
 574 // ------------------------------------------------------------------------------------------
 575 // Token management for XSRF protection
 576 // Token should be used in any form which acts on data (create,update,delete,import...).
 577 if (!isset($_SESSION['tokens'])) $_SESSION['tokens']=array();  // Token are attached to the session.
 578
 579 // Returns a token.
 580 function getToken()
 581 {
 582     $rnd = sha1(uniqid('',true).'_'.mt_rand().$GLOBALS['salt']);  // We generate a random string.
 583     $_SESSION['tokens'][$rnd]=1;  // Store it on the server side.
 584     return $rnd;
 585 }
 586
 587 // Tells if a token is ok. Using this function will destroy the token.
 588 // true=token is ok.
 589 function tokenOk($token)
 590 {
 591     if (isset($_SESSION['tokens'][$token]))
 592     {
 593         unset($_SESSION['tokens'][$token]); // Token is used: destroy it.
 594         return true; // Token is ok.
 595     }
 596     return false; // Wrong token, or already used.
 597 }
 598
 599 // ------------------------------------------------------------------------------------------
 600 /* This class is in charge of building the final page.
 601    (This is basically a wrapper around RainTPL which pre-fills some fields.)
 602    p = new pageBuilder;
 603    p.assign('myfield','myvalue');
 604    p.renderPage('mytemplate');
 605
 606 */
 607 class pageBuilder
 608 {
 609     private $tpl; // RainTPL template
 610
 611     function __construct()
 612     {
 613         $this->tpl=false;
 614     }
 615
 616     private function initialize()
 617     {
 618         $this->tpl = new RainTPL;
 619         $this->tpl->assign('newversion',checkUpdate());
 620         $this->tpl->assign('feedurl',htmlspecialchars(indexUrl()));
 621         $searchcrits=''; // Search criteria
 622         if (!empty($_GET['searchtags'])) $searchcrits.='&searchtags='.urlencode($_GET['searchtags']);
 623         elseif (!empty($_GET['searchterm'])) $searchcrits.='&searchterm='.urlencode($_GET['searchterm']);
 624         $this->tpl->assign('searchcrits',$searchcrits);
 625         $this->tpl->assign('source',indexUrl());
 626         $this->tpl->assign('version',shaarli_version);
 627         $this->tpl->assign('scripturl',indexUrl());
 628         $this->tpl->assign('pagetitle','Shaarli');
 629         $this->tpl->assign('privateonly',!empty($_SESSION['privateonly'])); // Show only private links ?
 630         if (!empty($GLOBALS['title'])) $this->tpl->assign('pagetitle',$GLOBALS['title']);
 631         if (!empty($GLOBALS['pagetitle'])) $this->tpl->assign('pagetitle',$GLOBALS['pagetitle']);
 632         $this->tpl->assign('shaarlititle',empty($GLOBALS['title']) ? 'Shaarli': $GLOBALS['title'] );
 633         return;
 634     }
 635
 636     // The following assign() method is basically the same as RainTPL (except that it's lazy)
 637     public function assign($what,$where)
 638     {
 639         if ($this->tpl===false) $this->initialize(); // Lazy initialization
 640         $this->tpl->assign($what,$where);
 641     }
 642
 643     // Render a specific page (using a template).
 644     // eg. pb.renderPage('picwall')
 645     public function renderPage($page)
 646     {
 647         if ($this->tpl===false) $this->initialize(); // Lazy initialization
 648         $this->tpl->draw($page);
 649     }
 650 }
 651
 652 // ------------------------------------------------------------------------------------------
 653 /* Data storage for links.
 654    This object behaves like an associative array.
 655    Example:
 656       $mylinks = new linkdb();
 657       echo $mylinks['20110826_161819']['title'];
 658       foreach($mylinks as $link)
 659          echo $link['title'].' at url '.$link['url'].' ; description:'.$link['description'];
 660
 661    Available keys:
 662        title : Title of the link
 663        url : URL of the link. Can be absolute or relative. Relative URLs are permalinks (eg.'?m-ukcw')
 664        description : description of the entry
 665        private : Is this link private ? 0=no, other value=yes
 666        linkdate : date of the creation of this entry, in the form YYYYMMDD_HHMMSS (eg.'20110914_192317')
 667        tags : tags attached to this entry (separated by spaces)
 668
 669    We implement 3 interfaces:
 670      - ArrayAccess so that this object behaves like an associative array.
 671      - Iterator so that this object can be used in foreach() loops.
 672      - Countable interface so that we can do a count() on this object.
 673 */
 674 class linkdb implements Iterator, Countable, ArrayAccess
 675 {
 676     private $links; // List of links (associative array. Key=linkdate (eg. "20110823_124546"), value= associative array (keys:title,description...)
 677     private $urls;  // List of all recorded URLs (key=url, value=linkdate) for fast reserve search (url-->linkdate)
 678     private $keys;  // List of linkdate keys (for the Iterator interface implementation)
 679     private $position; // Position in the $this->keys array. (for the Iterator interface implementation.)
 680     private $loggedin; // Is the used logged in ? (used to filter private links)
 681
 682     // Constructor:
 683     function __construct($isLoggedIn)
 684     // Input : $isLoggedIn : is the used logged in ?
 685     {
 686         $this->loggedin = $isLoggedIn;
 687         $this->checkdb(); // Make sure data file exists.
 688         $this->readdb();  // Then read it.
 689     }
 690
 691     // ---- Countable interface implementation
 692     public function count() { return count($this->links); }
 693
 694     // ---- ArrayAccess interface implementation
 695     public function offsetSet($offset, $value)
 696     {
 697         if (!$this->loggedin) die('You are not authorized to add a link.');
 698         if (empty($value['linkdate']) || empty($value['url'])) die('Internal Error: A link should always have a linkdate and url.');
 699         if (empty($offset)) die('You must specify a key.');
 700         $this->links[$offset] = $value;
 701         $this->urls[$value['url']]=$offset;
 702     }
 703     public function offsetExists($offset) { return array_key_exists($offset,$this->links); }
 704     public function offsetUnset($offset)
 705     {
 706         if (!$this->loggedin) die('You are not authorized to delete a link.');
 707         $url = $this->links[$offset]['url']; unset($this->urls[$url]);
 708         unset($this->links[$offset]);
 709     }
 710     public function offsetGet($offset) { return isset($this->links[$offset]) ? $this->links[$offset] : null; }
 711
 712     // ---- Iterator interface implementation
 713     function rewind() { $this->keys=array_keys($this->links); rsort($this->keys); $this->position=0; } // Start over for iteration, ordered by date (latest first).
 714     function key() { return $this->keys[$this->position]; } // current key
 715     function current() { return $this->links[$this->keys[$this->position]]; } // current value
 716     function next() { ++$this->position; } // go to next item
 717     function valid() { return isset($this->keys[$this->position]); }    // Check if current position is valid.
 718
 719     // ---- Misc methods
 720     private function checkdb() // Check if db directory and file exists.
 721     {
 722         if (!file_exists($GLOBALS['config']['DATASTORE'])) // Create a dummy database for example.
 723         {
 724              $this->links = array();
 725              $link = array('title'=>'Shaarli - sebsauvage.net','url'=>'http://sebsauvage.net/wiki/doku.php?id=php:shaarli','description'=>'Welcome to Shaarli ! This is a bookmark. To edit or delete me, you must first login.','private'=>0,'linkdate'=>'20110914_190000','tags'=>'opensource software');
 726              $this->links[$link['linkdate']] = $link;
 727              $link = array('title'=>'My secret stuff... - Pastebin.com','url'=>'http://pastebin.com/smCEEeSn','description'=>'SShhhh!!  I\'m a private link only YOU can see. You can delete me too.','private'=>1,'linkdate'=>'20110914_074522','tags'=>'secretstuff');
 728              $this->links[$link['linkdate']] = $link;
 729              file_put_contents($GLOBALS['config']['DATASTORE'], PHPPREFIX.base64_encode(gzdeflate(serialize($this->links))).PHPSUFFIX); // Write database to disk
 730         }
 731     }
 732
 733     // Read database from disk to memory
 734     private function readdb()
 735     {
 736         // Read data
 737         $this->links=(file_exists($GLOBALS['config']['DATASTORE']) ? unserialize(gzinflate(base64_decode(substr(file_get_contents($GLOBALS['config']['DATASTORE']),strlen(PHPPREFIX),-strlen(PHPSUFFIX))))) : array() );
 738         // Note that gzinflate is faster than gzuncompress. See: http://www.php.net/manual/en/function.gzdeflate.php#96439
 739
 740         // If user is not logged in, filter private links.
 741         if (!$this->loggedin)
 742         {
 743             $toremove=array();
 744             foreach($this->links as $link) { if ($link['private']!=0) $toremove[]=$link['linkdate']; }
 745             foreach($toremove as $linkdate) { unset($this->links[$linkdate]); }
 746         }
 747
 748         // Keep the list of the mapping URLs-->linkdate up-to-date.
 749         $this->urls=array();
 750         foreach($this->links as $link) { $this->urls[$link['url']]=$link['linkdate']; }
 751     }
 752
 753     // Save database from memory to disk.
 754     public function savedb()
 755     {
 756         if (!$this->loggedin) die('You are not authorized to change the database.');
 757         file_put_contents($GLOBALS['config']['DATASTORE'], PHPPREFIX.base64_encode(gzdeflate(serialize($this->links))).PHPSUFFIX);
 758         invalidateCaches();
 759     }
 760
 761     // Returns the link for a given URL (if it exists). false it does not exist.
 762     public function getLinkFromUrl($url)
 763     {
 764         if (isset($this->urls[$url])) return $this->links[$this->urls[$url]];
 765         return false;
 766     }
 767
 768     // Case insentitive search among links (in url, title and description). Returns filtered list of links.
 769     // eg. print_r($mydb->filterFulltext('hollandais'));
 770     public function filterFulltext($searchterms)
 771     {
 772         // FIXME: explode(' ',$searchterms) and perform a AND search.
 773         // FIXME: accept double-quotes to search for a string "as is" ?
 774         $filtered=array();
 775         $s = strtolower($searchterms);
 776         foreach($this->links as $l)
 777         {
 778             $found=   (strpos(strtolower($l['title']),$s)!==false)
 779                    || (strpos(strtolower($l['description']),$s)!==false)
 780                    || (strpos(strtolower($l['url']),$s)!==false)
 781                    || (strpos(strtolower($l['tags']),$s)!==false);
 782             if ($found) $filtered[$l['linkdate']] = $l;
 783         }
 784         krsort($filtered);
 785         return $filtered;
 786     }
 787
 788     // Filter by tag.
 789     // You can specify one or more tags (tags can be separated by space or comma).
 790     // eg. print_r($mydb->filterTags('linux programming'));
 791     public function filterTags($tags,$casesensitive=false)
 792     {
 793         $t = str_replace(',',' ',($casesensitive?$tags:strtolower($tags)));
 794         $searchtags=explode(' ',$t);
 795         $filtered=array();
 796         foreach($this->links as $l)
 797         {
 798             $linktags = explode(' ',($casesensitive?$l['tags']:strtolower($l['tags'])));
 799             if (count(array_intersect($linktags,$searchtags)) == count($searchtags))
 800                 $filtered[$l['linkdate']] = $l;
 801         }
 802         krsort($filtered);
 803         return $filtered;
 804     }
 805
 806     // Filter by day. Day must be in the form 'YYYYMMDD' (eg. '20120125')
 807     // Sort order is: older articles first.
 808     // eg. print_r($mydb->filterDay('20120125'));
 809     public function filterDay($day)
 810     {
 811         $filtered=array();
 812         foreach($this->links as $l)
 813         {
 814             if (startsWith($l['linkdate'],$day)) $filtered[$l['linkdate']] = $l;
 815         }
 816         ksort($filtered);
 817         return $filtered;
 818     }
 819     // Filter by smallHash.
 820     // Only 1 article is returned.
 821     public function filterSmallHash($smallHash)
 822     {
 823         $filtered=array();
 824         foreach($this->links as $l)
 825         {
 826             if ($smallHash==smallHash($l['linkdate'])) // Yes, this is ugly and slow
 827             {
 828                 $filtered[$l['linkdate']] = $l;
 829                 return $filtered;
 830             }
 831         }
 832         return $filtered;
 833     }
 834
 835     // Returns the list of all tags
 836     // Output: associative array key=tags, value=0
 837     public function allTags()
 838     {
 839         $tags=array();
 840         foreach($this->links as $link)
 841             foreach(explode(' ',$link['tags']) as $tag)
 842                 if (!empty($tag)) $tags[$tag]=(empty($tags[$tag]) ? 1 : $tags[$tag]+1);
 843         arsort($tags); // Sort tags by usage (most used tag first)
 844         return $tags;
 845     }
 846
 847     // Returns the list of days containing articles (oldest first)
 848     // Output: An array containing days (in format YYYYMMDD).
 849     public function days()
 850     {
 851         $linkdays=array();
 852         foreach(array_keys($this->links) as $day)
 853         {
 854             $linkdays[substr($day,0,8)]=0;
 855         }
 856         $linkdays=array_keys($linkdays);
 857         sort($linkdays);
 858         return $linkdays;
 859     }
 860 }
 861
 862 // ------------------------------------------------------------------------------------------
 863 // Ouput the last 50 links in RSS 2.0 format.
 864 function showRSS()
 865 {
 866     header('Content-Type: application/rss+xml; charset=utf-8');
 867
 868     // $usepermalink : If true, use permalink instead of final link.
 869     // User just has to add 'permalink' in URL parameters. eg. http://mysite.com/shaarli/?do=rss&permalinks
 870     $usepermalinks = isset($_GET['permalinks']);
 871
 872     // Cache system
 873     $query = $_SERVER["QUERY_STRING"];
 874     $cache = new pageCache(pageUrl(),startsWith($query,'do=rss') && !isLoggedIn());
 875     $cached = $cache->cachedVersion(); if (!empty($cached)) { echo $cached; exit; }
 876
 877     // If cached was not found (or not usable), then read the database and build the response:
 878     $LINKSDB=new linkdb(isLoggedIn() || $GLOBALS['config']['OPEN_SHAARLI']);  // Read links from database (and filter private links if used it not logged in).
 879
 880     // Optionnaly filter the results:
 881     $linksToDisplay=array();
 882     if (!empty($_GET['searchterm'])) $linksToDisplay = $LINKSDB->filterFulltext($_GET['searchterm']);
 883     elseif (!empty($_GET['searchtags']))   $linksToDisplay = $LINKSDB->filterTags(trim($_GET['searchtags']));
 884     else $linksToDisplay = $LINKSDB;
 885
 886     $pageaddr=htmlspecialchars(indexUrl());
 887     echo '<?xml version="1.0" encoding="UTF-8"?><rss version="2.0" xmlns:content="http://purl.org/rss/1.0/modules/content/">';
 888     echo '<channel><title>'.htmlspecialchars($GLOBALS['title']).'</title><link>'.$pageaddr.'</link>';
 889     echo '<description>Shared links</description><language>en-en</language><copyright>'.$pageaddr.'</copyright>'."\n\n";
 890     if (!empty($GLOBALS['config']['PUBSUBHUB_URL']))
 891     {
 892         echo '<!-- PubSubHubbub Discovery -->';
 893         echo '<link rel="hub" href="'.htmlspecialchars($GLOBALS['config']['PUBSUBHUB_URL']).'" xmlns="http://www.w3.org/2005/Atom" />';
 894         echo '<link rel="self" href="'.htmlspecialchars($pageaddr).'?do=rss" xmlns="http://www.w3.org/2005/Atom" />';
 895         echo '<!-- End Of PubSubHubbub Discovery -->';
 896     }
 897     $i=0;
 898     $keys=array(); foreach($linksToDisplay as $key=>$value) { $keys[]=$key; }  // No, I can't use array_keys().
 899     while ($i<50 && $i<count($keys))
 900     {
 901         $link = $linksToDisplay[$keys[$i]];
 902         $guid = $pageaddr.'?'.smallHash($link['linkdate']);
 903         $rfc822date = linkdate2rfc822($link['linkdate']);
 904         $absurl = htmlspecialchars($link['url']);
 905         if (startsWith($absurl,'?')) $absurl=$pageaddr.$absurl;  // make permalink URL absolute
 906         if ($usepermalinks===true)
 907             echo '<item><title>'.htmlspecialchars($link['title']).'</title><guid isPermaLink="false">'.$guid.'</guid><link>'.$guid.'</link>';
 908         else
 909             echo '<item><title>'.htmlspecialchars($link['title']).'</title><guid isPermaLink="false">'.$guid.'</guid><link>'.$absurl.'</link>';
 910         if (!$GLOBALS['config']['HIDE_TIMESTAMPS'] || isLoggedIn()) echo '<pubDate>'.htmlspecialchars($rfc822date)."</pubDate>\n";
 911         if ($link['tags']!='') // Adding tags to each RSS entry (as mentioned in RSS specification)
 912         {
 913             foreach(explode(' ',$link['tags']) as $tag) { echo '<category domain="'.htmlspecialchars($pageaddr).'">'.htmlspecialchars($tag).'</category>'."\n"; }
 914         }
 915
 916         // Add permalink in description
 917         $descriptionlink = '(<a href="'.$guid.'">Permalink</a>)';
 918         // If user wants permalinks first, put the final link in description
 919         if ($usepermalinks===true) $descriptionlink = '(<a href="'.$absurl.'">Link</a>)';
 920         if (strlen($link['description'])>0) $descriptionlink = '<br>'.$descriptionlink;
 921         echo '<description><![CDATA['.nl2br(keepMultipleSpaces(text2clickable(htmlspecialchars($link['description'])))).$descriptionlink.']]></description>'."\n</item>\n";
 922         $i++;
 923     }
 924     echo '</channel></rss>';
 925
 926     $cache->cache(ob_get_contents());
 927     ob_end_flush();
 928     exit;
 929 }
 930
 931 // ------------------------------------------------------------------------------------------
 932 // Ouput the last 50 links in ATOM format.
 933 function showATOM()
 934 {
 935     header('Content-Type: application/atom+xml; charset=utf-8');
 936
 937     // $usepermalink : If true, use permalink instead of final link.
 938     // User just has to add 'permalink' in URL parameters. eg. http://mysite.com/shaarli/?do=atom&permalinks
 939     $usepermalinks = isset($_GET['permalinks']);
 940
 941     // Cache system
 942     $query = $_SERVER["QUERY_STRING"];
 943     $cache = new pageCache(pageUrl(),startsWith($query,'do=atom') && !isLoggedIn());
 944     $cached = $cache->cachedVersion(); if (!empty($cached)) { echo $cached; exit; }
 945     // If cached was not found (or not usable), then read the database and build the response:
 946
 947     $LINKSDB=new linkdb(isLoggedIn() || $GLOBALS['config']['OPEN_SHAARLI']);  // Read links from database (and filter private links if used it not logged in).
 948
 949
 950     // Optionnaly filter the results:
 951     $linksToDisplay=array();
 952     if (!empty($_GET['searchterm'])) $linksToDisplay = $LINKSDB->filterFulltext($_GET['searchterm']);
 953     elseif (!empty($_GET['searchtags']))   $linksToDisplay = $LINKSDB->filterTags(trim($_GET['searchtags']));
 954     else $linksToDisplay = $LINKSDB;
 955
 956     $pageaddr=htmlspecialchars(indexUrl());
 957     $latestDate = '';
 958     $entries='';
 959     $i=0;
 960     $keys=array(); foreach($linksToDisplay as $key=>$value) { $keys[]=$key; }  // No, I can't use array_keys().
 961     while ($i<50 && $i<count($keys))
 962     {
 963         $link = $linksToDisplay[$keys[$i]];
 964         $guid = $pageaddr.'?'.smallHash($link['linkdate']);
 965         $iso8601date = linkdate2iso8601($link['linkdate']);
 966         $latestDate = max($latestDate,$iso8601date);
 967         $absurl = htmlspecialchars($link['url']);
 968         if (startsWith($absurl,'?')) $absurl=$pageaddr.$absurl;  // make permalink URL absolute
 969         $entries.='<entry><title>'.htmlspecialchars($link['title']).'</title>';
 970         if ($usepermalinks===true)
 971             $entries.='<link href="'.$guid.'" /><id>'.$guid.'</id>';
 972         else
 973             $entries.='<link href="'.$absurl.'" /><id>'.$guid.'</id>';
 974         if (!$GLOBALS['config']['HIDE_TIMESTAMPS'] || isLoggedIn()) $entries.='<updated>'.htmlspecialchars($iso8601date).'</updated>';
 975
 976         // Add permalink in description
 977         $descriptionlink = htmlspecialchars('(<a href="'.$guid.'">Permalink</a>)');
 978         // If user wants permalinks first, put the final link in description
 979         if ($usepermalinks===true) $descriptionlink = htmlspecialchars('(<a href="'.$absurl.'">Link</a>)');
 980         if (strlen($link['description'])>0) $descriptionlink = '&lt;br&gt;'.$descriptionlink;
 981
 982         $entries.='<content type="html">'.htmlspecialchars(nl2br(keepMultipleSpaces(text2clickable(htmlspecialchars($link['description']))))).$descriptionlink."</content>\n";
 983         if ($link['tags']!='') // Adding tags to each ATOM entry (as mentioned in ATOM specification)
 984         {
 985             foreach(explode(' ',$link['tags']) as $tag)
 986                 { $entries.='<category scheme="'.htmlspecialchars($pageaddr,ENT_QUOTES).'" term="'.htmlspecialchars($tag,ENT_QUOTES).'" />'."\n"; }
 987         }
 988         $entries.="</entry>\n";
 989         $i++;
 990     }
 991     $feed='<?xml version="1.0" encoding="UTF-8"?><feed xmlns="http://www.w3.org/2005/Atom">';
 992     $feed.='<title>'.htmlspecialchars($GLOBALS['title']).'</title>';
 993     if (!$GLOBALS['config']['HIDE_TIMESTAMPS'] || isLoggedIn()) $feed.='<updated>'.htmlspecialchars($latestDate).'</updated>';
 994     $feed.='<link rel="self" href="'.htmlspecialchars(serverUrl().$_SERVER["REQUEST_URI"]).'" />';
 995     if (!empty($GLOBALS['config']['PUBSUBHUB_URL']))
 996     {
 997         $feed.='<!-- PubSubHubbub Discovery -->';
 998         $feed.='<link rel="hub" href="'.htmlspecialchars($GLOBALS['config']['PUBSUBHUB_URL']).'" />';
 999         $feed.='<!-- End Of PubSubHubbub Discovery -->';
1000     }
1001     $feed.='<author><name>'.htmlspecialchars($pageaddr).'</name><uri>'.htmlspecialchars($pageaddr).'</uri></author>';
1002     $feed.='<id>'.htmlspecialchars($pageaddr).'</id>'."\n\n"; // Yes, I know I should use a real IRI (RFC3987), but the site URL will do.
1003     $feed.=$entries;
1004     $feed.='</feed>';
1005     echo $feed;
1006
1007     $cache->cache(ob_get_contents());
1008     ob_end_flush();
1009     exit;
1010 }
1011
1012 // ------------------------------------------------------------------------------------------
1013 // Daily RSS feed: 1 RSS entry per day giving all the links on that day.
1014 // Gives the last 7 days (which have links).
1015 // This RSS feed cannot be filtered.
1016 function showDailyRSS()
1017 {
1018     // Cache system
1019     $query = $_SERVER["QUERY_STRING"];
1020     $cache = new pageCache(pageUrl(),startsWith($query,'do=dailyrss') && !isLoggedIn());
1021     $cached = $cache->cachedVersion(); if (!empty($cached)) { echo $cached; exit; }
1022     // If cached was not found (or not usable), then read the database and build the response:
1023     $LINKSDB=new linkdb(isLoggedIn() || $GLOBALS['config']['OPEN_SHAARLI']);  // Read links from database (and filter private links if used it not logged in).
1024
1025     /* Some Shaarlies may have very few links, so we need to look
1026        back in time (rsort()) until we have enough days ($nb_of_days).
1027     */
1028     $linkdates=array(); foreach($LINKSDB as $linkdate=>$value) { $linkdates[]=$linkdate; }
1029     rsort($linkdates);
1030     $nb_of_days=7; // We take 7 days.
1031     $today=Date('Ymd');
1032     $days=array();
1033     foreach($linkdates as $linkdate)
1034     {
1035         $day=substr($linkdate,0,8); // Extract day (without time)
1036         if (strcmp($day,$today)<0)
1037         {
1038             if (empty($days[$day])) $days[$day]=array();
1039             $days[$day][]=$linkdate;
1040         }
1041         if (count($days)>$nb_of_days) break; // Have we collected enough days ?
1042     }
1043
1044     // Build the RSS feed.
1045     header('Content-Type: application/rss+xml; charset=utf-8');
1046     $pageaddr=htmlspecialchars(indexUrl());
1047     echo '<?xml version="1.0" encoding="UTF-8"?><rss version="2.0">';
1048     echo '<channel><title>Daily - '.htmlspecialchars($GLOBALS['title']).'</title><link>'.$pageaddr.'</link>';
1049     echo '<description>Daily shared links</description><language>en-en</language><copyright>'.$pageaddr.'</copyright>'."\n";
1050
1051     foreach($days as $day=>$linkdates) // For each day.
1052     {
1053         $daydate = utf8_encode(strftime('%A %d, %B %Y',linkdate2timestamp($day.'_000000'))); // Full text date
1054         $rfc822date = linkdate2rfc822($day.'_000000');
1055         $absurl=htmlspecialchars(indexUrl().'?do=daily&day='.$day);  // Absolute URL of the corresponding "Daily" page.
1056         echo '<item><title>'.htmlspecialchars($GLOBALS['title'].' - '.$daydate).'</title><guid>'.$absurl.'</guid><link>'.$absurl.'</link>';
1057         echo '<pubDate>'.htmlspecialchars($rfc822date)."</pubDate>";
1058
1059         // Build the HTML body of this RSS entry.
1060         $html='';
1061         $href='';
1062         $links=array();
1063         // We pre-format some fields for proper output.
1064         foreach($linkdates as $linkdate)
1065         {
1066             $l = $LINKSDB[$linkdate];
1067             $l['formatedDescription']=nl2br(keepMultipleSpaces(text2clickable(htmlspecialchars($l['description']))));
1068             $l['thumbnail'] = thumbnail($l['url']);
1069             $l['localdate']=linkdate2locale($l['linkdate']);
1070             if (startsWith($l['url'],'?')) $l['url']=indexUrl().$l['url'];  // make permalink URL absolute
1071             $links[$linkdate]=$l;
1072         }
1073         // Then build the HTML for this day:
1074         $tpl = new RainTPL;
1075         $tpl->assign('links',$links);
1076         $html = $tpl->draw('dailyrss',$return_string=true);
1077         echo "\n";
1078         echo '<description><![CDATA['.$html.']]></description>'."\n</item>\n\n";
1079
1080     }
1081     echo '</channel></rss>';
1082
1083     $cache->cache(ob_get_contents());
1084     ob_end_flush();
1085     exit;
1086 }
1087
1088 // "Daily" page.
1089 function showDaily()
1090 {
1091     $LINKSDB=new linkdb(isLoggedIn() || $GLOBALS['config']['OPEN_SHAARLI']);  // Read links from database (and filter private links if used it not logged in).
1092
1093
1094     $day=Date('Ymd',strtotime('-1 day')); // Yesterday, in format YYYYMMDD.
1095     if (isset($_GET['day'])) $day=$_GET['day'];
1096
1097     $days = $LINKSDB->days();
1098     $i = array_search($day,$days);
1099     if ($i==false) { $i=count($days)-1; $day=$days[$i]; }
1100     $previousday='';
1101     $nextday='';
1102     if ($i!==false)
1103     {
1104         if ($i>1) $previousday=$days[$i-1];
1105         if ($i<count($days)-1) $nextday=$days[$i+1];
1106     }
1107
1108     $linksToDisplay=$LINKSDB->filterDay($day);
1109     // We pre-format some fields for proper output.
1110     foreach($linksToDisplay as $key=>$link)
1111     {
1112         $taglist = explode(' ',$link['tags']);
1113         uasort($taglist, 'strcasecmp');
1114         $linksToDisplay[$key]['taglist']=$taglist;
1115         $linksToDisplay[$key]['formatedDescription']=nl2br(keepMultipleSpaces(text2clickable(htmlspecialchars($link['description']))));
1116         $linksToDisplay[$key]['thumbnail'] = thumbnail($link['url']);
1117     }
1118
1119     /* We need to spread the articles on 3 columns.
1120        I did not want to use a javascript lib like http://masonry.desandro.com/
1121        so I manually spread entries with a simple method: I roughly evaluate the
1122        height of a div according to title and description length.
1123     */
1124     $columns=array(array(),array(),array()); // Entries to display, for each column.
1125     $fill=array(0,0,0);  // Rough estimate of columns fill.
1126     foreach($linksToDisplay as $key=>$link)
1127     {
1128         // Roughly estimate length of entry (by counting characters)
1129         // Title: 30 chars = 1 line. 1 line is 30 pixels height.
1130         // Description: 836 characters gives roughly 342 pixel height.
1131         // This is not perfect, but it's usually ok.
1132         $length=strlen($link['title'])+(342*strlen($link['description']))/836;
1133         if ($link['thumbnail']) $length +=100; // 1 thumbnails roughly takes 100 pixels height.
1134         // Then put in column which is the less filled:
1135         $smallest=min($fill); // find smallest value in array.
1136         $index=array_search($smallest,$fill); // find index of this smallest value.
1137         array_push($columns[$index],$link); // Put entry in this column.
1138         $fill[$index]+=$length;
1139     }
1140     $PAGE = new pageBuilder;
1141     $PAGE->assign('linksToDisplay',$linksToDisplay);
1142     $PAGE->assign('linkcount',count($LINKSDB));
1143     $PAGE->assign('col1',$columns[0]);
1144     $PAGE->assign('col1',$columns[0]);
1145     $PAGE->assign('col2',$columns[1]);
1146     $PAGE->assign('col3',$columns[2]);
1147     $PAGE->assign('day',utf8_encode(strftime('%A %d, %B %Y',linkdate2timestamp($day.'_000000'))));
1148     $PAGE->assign('previousday',$previousday);
1149     $PAGE->assign('nextday',$nextday);
1150     $PAGE->renderPage('daily');
1151     exit;
1152 }
1153
1154
1155 // ------------------------------------------------------------------------------------------
1156 // Render HTML page (according to URL parameters and user rights)
1157 function renderPage()
1158 {
1159     $LINKSDB=new linkdb(isLoggedIn() || $GLOBALS['config']['OPEN_SHAARLI']);  // Read links from database (and filter private links if used it not logged in).
1160
1161     // -------- Display login form.
1162     if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=login'))
1163     {
1164         if ($GLOBALS['config']['OPEN_SHAARLI']) { header('Location: ?'); exit; }  // No need to login for open Shaarli
1165         $token=''; if (ban_canLogin()) $token=getToken(); // Do not waste token generation if not useful.
1166         $PAGE = new pageBuilder;
1167         $PAGE->assign('token',$token);
1168         $PAGE->assign('returnurl',(isset($_SERVER['HTTP_REFERER']) ? $_SERVER['HTTP_REFERER']:''));
1169         $PAGE->renderPage('loginform');
1170         exit;
1171     }
1172     // -------- User wants to logout.
1173     if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=logout'))
1174     {
1175         invalidateCaches();
1176         logout();
1177         header('Location: ?');
1178         exit;
1179     }
1180
1181     // -------- Picture wall
1182     if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=picwall'))
1183     {
1184         // Optionnaly filter the results:
1185         $links=array();
1186         if (!empty($_GET['searchterm'])) $links = $LINKSDB->filterFulltext($_GET['searchterm']);
1187         elseif (!empty($_GET['searchtags']))   $links = $LINKSDB->filterTags(trim($_GET['searchtags']));
1188         else $links = $LINKSDB;
1189         $body='';
1190         $linksToDisplay=array();
1191
1192         // Get only links which have a thumbnail.
1193         foreach($links as $link)
1194         {
1195             $permalink='?'.htmlspecialchars(smallhash($link['linkdate']),ENT_QUOTES);
1196             $thumb=lazyThumbnail($link['url'],$permalink);
1197             if ($thumb!='') // Only output links which have a thumbnail.
1198             {
1199                 $link['thumbnail']=$thumb; // Thumbnail HTML code.
1200                 $link['permalink']=$permalink;
1201                 $linksToDisplay[]=$link; // Add to array.
1202             }
1203         }
1204         $PAGE = new pageBuilder;
1205         $PAGE->assign('linkcount',count($LINKSDB));
1206         $PAGE->assign('linksToDisplay',$linksToDisplay);
1207         $PAGE->renderPage('picwall');
1208         exit;
1209     }
1210
1211     // -------- Tag cloud
1212     if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=tagcloud'))
1213     {
1214         $tags= $LINKSDB->allTags();
1215         // We sort tags alphabetically, then choose a font size according to count.
1216         // First, find max value.
1217         $maxcount=0; foreach($tags as $key=>$value) $maxcount=max($maxcount,$value);
1218         ksort($tags);
1219         $tagList=array();
1220         foreach($tags as $key=>$value)
1221         {
1222             $tagList[$key] = array('count'=>$value,'size'=>max(40*$value/$maxcount,8));
1223         }
1224         $PAGE = new pageBuilder;
1225         $PAGE->assign('linkcount',count($LINKSDB));
1226         $PAGE->assign('tags',$tagList);
1227         $PAGE->renderPage('tagcloud');
1228         exit;
1229     }
1230
1231     // -------- User clicks on a tag in a link: The tag is added to the list of searched tags (searchtags=...)
1232     if (isset($_GET['addtag']))
1233     {
1234         // Get previous URL (http_referer) and add the tag to the searchtags parameters in query.
1235         if (empty($_SERVER['HTTP_REFERER'])) { header('Location: ?searchtags='.urlencode($_GET['addtag'])); exit; } // In case browser does not send HTTP_REFERER
1236         parse_str(parse_url($_SERVER['HTTP_REFERER'],PHP_URL_QUERY), $params);
1237         $params['searchtags'] = (empty($params['searchtags']) ?  trim($_GET['addtag']) : trim($params['searchtags']).' '.trim($_GET['addtag']));
1238         unset($params['page']); // We also remove page (keeping the same page has no sense, since the results are different)
1239         header('Location: ?'.http_build_query($params));
1240         exit;
1241     }
1242
1243     // -------- User clicks on a tag in result count: Remove the tag from the list of searched tags (searchtags=...)
1244     if (isset($_GET['removetag']))
1245     {
1246         // Get previous URL (http_referer) and remove the tag from the searchtags parameters in query.
1247         if (empty($_SERVER['HTTP_REFERER'])) { header('Location: ?'); exit; } // In case browser does not send HTTP_REFERER
1248         parse_str(parse_url($_SERVER['HTTP_REFERER'],PHP_URL_QUERY), $params);
1249         if (isset($params['searchtags']))
1250         {
1251             $tags = explode(' ',$params['searchtags']);
1252             $tags=array_diff($tags, array($_GET['removetag'])); // Remove value from array $tags.
1253             if (count($tags)==0) unset($params['searchtags']); else $params['searchtags'] = implode(' ',$tags);
1254             unset($params['page']); // We also remove page (keeping the same page has no sense, since the results are different)
1255         }
1256         header('Location: ?'.http_build_query($params));
1257         exit;
1258     }
1259
1260     // -------- User wants to change the number of links per page (linksperpage=...)
1261     if (isset($_GET['linksperpage']))
1262     {
1263         if (is_numeric($_GET['linksperpage'])) { $_SESSION['LINKS_PER_PAGE']=abs(intval($_GET['linksperpage'])); }
1264         header('Location: '.(empty($_SERVER['HTTP_REFERER'])?'?':$_SERVER['HTTP_REFERER']));
1265         exit;
1266     }
1267
1268     // -------- User wants to see only private links (toggle)
1269     if (isset($_GET['privateonly']))
1270     {
1271         if (empty($_SESSION['privateonly']))
1272         {
1273             $_SESSION['privateonly']=1; // See only private links
1274         }
1275         else
1276         {
1277             unset($_SESSION['privateonly']); // See all links
1278         }
1279         header('Location: '.(empty($_SERVER['HTTP_REFERER'])?'?':$_SERVER['HTTP_REFERER']));
1280         exit;
1281     }
1282
1283     // -------- Handle other actions allowed for non-logged in users:
1284     if (!isLoggedIn())
1285     {
1286         // User tries to post new link but is not loggedin:
1287         // Show login screen, then redirect to ?post=...
1288         if (isset($_GET['post']))
1289         {
1290             header('Location: ?do=login&post='.urlencode($_GET['post']).(!empty($_GET['title'])?'&title='.urlencode($_GET['title']):'').(!empty($_GET['source'])?'&source='.urlencode($_GET['source']):'')); // Redirect to login page, then back to post link.
1291             exit;
1292         }
1293         $PAGE = new pageBuilder;
1294         buildLinkList($PAGE,$LINKSDB); // Compute list of links to display
1295         $PAGE->renderPage('linklist');
1296         exit; // Never remove this one ! All operations below are reserved for logged in user.
1297     }
1298
1299     // -------- All other functions are reserved for the registered user:
1300
1301     // -------- Display the Tools menu if requested (import/export/bookmarklet...)
1302     if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=tools'))
1303     {
1304         $PAGE = new pageBuilder;
1305         $PAGE->assign('linkcount',count($LINKSDB));
1306         $PAGE->assign('pageabsaddr',indexUrl());
1307         $PAGE->renderPage('tools');
1308         exit;
1309     }
1310
1311     // -------- User wants to change his/her password.
1312     if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=changepasswd'))
1313     {
1314         if ($GLOBALS['config']['OPEN_SHAARLI']) die('You are not supposed to change a password on an Open Shaarli.');
1315         if (!empty($_POST['setpassword']) && !empty($_POST['oldpassword']))
1316         {
1317             if (!tokenOk($_POST['token'])) die('Wrong token.'); // Go away !
1318
1319             // Make sure old password is correct.
1320             $oldhash = sha1($_POST['oldpassword'].$GLOBALS['login'].$GLOBALS['salt']);
1321             if ($oldhash!=$GLOBALS['hash']) { echo '<script language="JavaScript">alert("The old password is not correct.");document.location=\'?do=changepasswd\';</script>'; exit; }
1322             // Save new password
1323             $GLOBALS['salt'] = sha1(uniqid('',true).'_'.mt_rand()); // Salt renders rainbow-tables attacks useless.
1324             $GLOBALS['hash'] = sha1($_POST['setpassword'].$GLOBALS['login'].$GLOBALS['salt']);
1325             writeConfig();
1326             echo '<script language="JavaScript">alert("Your password has been changed.");document.location=\'?do=tools\';</script>';
1327             exit;
1328         }
1329         else // show the change password form.
1330         {
1331             $PAGE = new pageBuilder;
1332             $PAGE->assign('linkcount',count($LINKSDB));
1333             $PAGE->assign('token',getToken());
1334             $PAGE->renderPage('changepassword');
1335             exit;
1336         }
1337     }
1338
1339     // -------- User wants to change configuration
1340     if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=configure'))
1341     {
1342         if (!empty($_POST['title']) )
1343         {
1344             if (!tokenOk($_POST['token'])) die('Wrong token.'); // Go away !
1345             $tz = 'UTC';
1346             if (!empty($_POST['continent']) && !empty($_POST['city']))
1347                 if (isTZvalid($_POST['continent'],$_POST['city']))
1348                     $tz = $_POST['continent'].'/'.$_POST['city'];
1349             $GLOBALS['timezone'] = $tz;
1350             $GLOBALS['title']=$_POST['title'];
1351             $GLOBALS['redirector']=$_POST['redirector'];
1352             $GLOBALS['disablesessionprotection']=!empty($_POST['disablesessionprotection']);
1353             writeConfig();
1354             echo '<script language="JavaScript">alert("Configuration was saved.");document.location=\'?do=tools\';</script>';
1355             exit;
1356         }
1357         else // Show the configuration form.
1358         {
1359             $PAGE = new pageBuilder;
1360             $PAGE->assign('linkcount',count($LINKSDB));
1361             $PAGE->assign('token',getToken());
1362             $PAGE->assign('title',htmlspecialchars( empty($GLOBALS['title']) ? '' : $GLOBALS['title'] , ENT_QUOTES));
1363             $PAGE->assign('redirector',htmlspecialchars( empty($GLOBALS['redirector']) ? '' : $GLOBALS['redirector'] , ENT_QUOTES));
1364             list($timezone_form,$timezone_js) = templateTZform($GLOBALS['timezone']);
1365             $PAGE->assign('timezone_form',$timezone_form); // FIXME: put entire tz form generation in template ?
1366             $PAGE->assign('timezone_js',$timezone_js);
1367             $PAGE->renderPage('configure');
1368             exit;
1369         }
1370     }
1371
1372     // -------- User wants to rename a tag or delete it
1373     if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=changetag'))
1374     {
1375         if (empty($_POST['fromtag']))
1376         {
1377             $PAGE = new pageBuilder;
1378             $PAGE->assign('linkcount',count($LINKSDB));
1379             $PAGE->assign('token',getToken());
1380             $PAGE->renderPage('changetag');
1381             exit;
1382         }
1383         if (!tokenOk($_POST['token'])) die('Wrong token.');
1384
1385         // Delete a tag:
1386         if (!empty($_POST['deletetag']) && !empty($_POST['fromtag']))
1387         {
1388             $needle=trim($_POST['fromtag']);
1389             $linksToAlter = $LINKSDB->filterTags($needle,true); // true for case-sensitive tag search.
1390             foreach($linksToAlter as $key=>$value)
1391             {
1392                 $tags = explode(' ',trim($value['tags']));
1393                 unset($tags[array_search($needle,$tags)]); // Remove tag.
1394                 $value['tags']=trim(implode(' ',$tags));
1395                 $LINKSDB[$key]=$value;
1396             }
1397             $LINKSDB->savedb(); // save to disk
1398             echo '<script language="JavaScript">alert("Tag was removed from '.count($linksToAlter).' links.");document.location=\'?\';</script>';
1399             exit;
1400         }
1401
1402         // Rename a tag:
1403         if (!empty($_POST['renametag']) && !empty($_POST['fromtag']) && !empty($_POST['totag']))
1404         {
1405             $needle=trim($_POST['fromtag']);
1406             $linksToAlter = $LINKSDB->filterTags($needle,true); // true for case-sensitive tag search.
1407             foreach($linksToAlter as $key=>$value)
1408             {
1409                 $tags = explode(' ',trim($value['tags']));
1410                 $tags[array_search($needle,$tags)] = trim($_POST['totag']); // Remplace tags value.
1411                 $value['tags']=trim(implode(' ',$tags));
1412                 $LINKSDB[$key]=$value;
1413             }
1414             $LINKSDB->savedb(); // save to disk
1415             echo '<script language="JavaScript">alert("Tag was renamed in '.count($linksToAlter).' links.");document.location=\'?searchtags='.urlencode($_POST['totag']).'\';</script>';
1416             exit;
1417         }
1418     }
1419
1420     // -------- User wants to add a link without using the bookmarklet: show form.
1421     if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=addlink'))
1422     {
1423         $PAGE = new pageBuilder;
1424         $PAGE->assign('linkcount',count($LINKSDB));
1425         $PAGE->renderPage('addlink');
1426         exit;
1427     }
1428
1429     // -------- User clicked the "Save" button when editing a link: Save link to database.
1430     if (isset($_POST['save_edit']))
1431     {
1432         if (!tokenOk($_POST['token'])) die('Wrong token.'); // Go away !
1433         $tags = trim(preg_replace('/\s\s+/',' ', $_POST['lf_tags'])); // Remove multiple spaces.
1434         $linkdate=$_POST['lf_linkdate'];
1435         $link = array('title'=>trim($_POST['lf_title']),'url'=>trim($_POST['lf_url']),'description'=>trim($_POST['lf_description']),'private'=>(isset($_POST['lf_private']) ? 1 : 0),
1436                       'linkdate'=>$linkdate,'tags'=>str_replace(',',' ',$tags));
1437         if ($link['title']=='') $link['title']=$link['url']; // If title is empty, use the URL as title.
1438         $LINKSDB[$linkdate] = $link;
1439         $LINKSDB->savedb(); // save to disk
1440         pubsubhub();
1441
1442         // If we are called from the bookmarklet, we must close the popup:
1443         if (isset($_GET['source']) && $_GET['source']=='bookmarklet') { echo '<script language="JavaScript">self.close();</script>'; exit; }
1444         $returnurl = ( isset($_POST['returnurl']) ? $_POST['returnurl'] : '?' );
1445         $returnurl .= '#'.smallHash($linkdate);  // Scroll to the link which has been edited.
1446         header('Location: '.$returnurl); // After saving the link, redirect to the page the user was on.
1447         exit;
1448     }
1449
1450     // -------- User clicked the "Cancel" button when editing a link.
1451     if (isset($_POST['cancel_edit']))
1452     {
1453         // If we are called from the bookmarklet, we must close the popup;
1454         if (isset($_GET['source']) && $_GET['source']=='bookmarklet') { echo '<script language="JavaScript">self.close();</script>'; exit; }
1455         $returnurl = ( isset($_POST['returnurl']) ? $_POST['returnurl'] : '?' );
1456         $returnurl .= '#'.smallHash($_POST['lf_linkdate']);  // Scroll to the link which has been edited.
1457         header('Location: '.$returnurl); // After canceling, redirect to the page the user was on.
1458         exit;
1459     }
1460
1461     // -------- User clicked the "Delete" button when editing a link : Delete link from database.
1462     if (isset($_POST['delete_link']))
1463     {
1464         if (!tokenOk($_POST['token'])) die('Wrong token.');
1465         // We do not need to ask for confirmation:
1466         // - confirmation is handled by javascript
1467         // - we are protected from XSRF by the token.
1468         $linkdate=$_POST['lf_linkdate'];
1469         unset($LINKSDB[$linkdate]);
1470         $LINKSDB->savedb(); // save to disk
1471
1472         // If we are called from the bookmarklet, we must close the popup:
1473         if (isset($_GET['source']) && $_GET['source']=='bookmarklet') { echo '<script language="JavaScript">self.close();</script>'; exit; }
1474         $returnurl = ( isset($_POST['returnurl']) ? $_POST['returnurl'] : '?' );
1475         if ($returnurl=='?') { $returnurl = (isset($_SERVER['HTTP_REFERER']) ? $_SERVER['HTTP_REFERER'] : '?'); }
1476         header('Location: '.$returnurl); // After deleting the link, redirect to the page the user was on.
1477         exit;
1478     }
1479
1480     // -------- User clicked the "EDIT" button on a link: Display link edit form.
1481     if (isset($_GET['edit_link']))
1482     {
1483         $link = $LINKSDB[$_GET['edit_link']];  // Read database
1484         if (!$link) { header('Location: ?'); exit; } // Link not found in database.
1485         $PAGE = new pageBuilder;
1486         $PAGE->assign('linkcount',count($LINKSDB));
1487         $PAGE->assign('link',$link);
1488         $PAGE->assign('link_is_new',false);
1489         $PAGE->assign('token',getToken()); // XSRF protection.
1490         $PAGE->assign('http_referer',(isset($_SERVER['HTTP_REFERER']) ? $_SERVER['HTTP_REFERER'] : ''));
1491         $PAGE->renderPage('editlink');
1492         exit;
1493     }
1494
1495     // -------- User want to post a new link: Display link edit form.
1496     if (isset($_GET['post']))
1497     {
1498         $url=$_GET['post'];
1499
1500         // We remove the annoying parameters added by FeedBurner and GoogleFeedProxy (?utm_source=...)
1501         $i=strpos($url,'&utm_source='); if ($i!==false) $url=substr($url,0,$i);
1502         $i=strpos($url,'?utm_source='); if ($i!==false) $url=substr($url,0,$i);
1503         $i=strpos($url,'#xtor=RSS-'); if ($i!==false) $url=substr($url,0,$i);
1504
1505         $link_is_new = false;
1506         $link = $LINKSDB->getLinkFromUrl($url); // Check if URL is not already in database (in this case, we will edit the existing link)
1507         if (!$link)
1508         {
1509             $link_is_new = true;  // This is a new link
1510             $linkdate = strval(date('Ymd_His'));
1511             $title = (empty($_GET['title']) ? '' : $_GET['title'] ); // Get title if it was provided in URL (by the bookmarklet).
1512             $description=''; $tags=''; $private=0;
1513             if (($url!='') && parse_url($url,PHP_URL_SCHEME)=='') $url = 'http://'.$url;
1514             // If this is an HTTP link, we try go get the page to extact the title (otherwise we will to straight to the edit form.)
1515             if (empty($title) && parse_url($url,PHP_URL_SCHEME)=='http')
1516             {
1517                 list($status,$headers,$data) = getHTTP($url,4); // Short timeout to keep the application responsive.
1518                 // FIXME: Decode charset according to specified in either 1) HTTP response headers or 2) <head> in html
1519                 if (strpos($status,'200 OK')!==false) $title=html_entity_decode(html_extract_title($data),ENT_QUOTES,'UTF-8');
1520
1521             }
1522             if ($url=='') $url='?'.smallHash($linkdate); // In case of empty URL, this is just a text (with a link that point to itself)
1523             $link = array('linkdate'=>$linkdate,'title'=>$title,'url'=>$url,'description'=>$description,'tags'=>$tags,'private'=>0);
1524         }
1525
1526         $PAGE = new pageBuilder;
1527         $PAGE->assign('linkcount',count($LINKSDB));
1528         $PAGE->assign('link',$link);
1529         $PAGE->assign('link_is_new',$link_is_new);
1530         $PAGE->assign('token',getToken()); // XSRF protection.
1531         $PAGE->assign('http_referer',(isset($_SERVER['HTTP_REFERER']) ? $_SERVER['HTTP_REFERER'] : ''));
1532         $PAGE->renderPage('editlink');
1533         exit;
1534     }
1535
1536     // -------- Export as Netscape Bookmarks HTML file.
1537     if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=export'))
1538     {
1539         if (empty($_GET['what']))
1540         {
1541             $PAGE = new pageBuilder;
1542             $PAGE->assign('linkcount',count($LINKSDB));
1543             $PAGE->renderPage('export');
1544             exit;
1545         }
1546         $exportWhat=$_GET['what'];
1547         if (!array_intersect(array('all','public','private'),array($exportWhat))) die('What are you trying to export ???');
1548
1549         header('Content-Type: text/html; charset=utf-8');
1550         header('Content-disposition: attachment; filename=bookmarks_'.$exportWhat.'_'.strval(date('Ymd_His')).'.html');
1551         $currentdate=date('Y/m/d H:i:s');
1552         echo <<<HTML
1553 <!DOCTYPE NETSCAPE-Bookmark-file-1>
1554 <!-- This is an automatically generated file.
1555      It will be read and overwritten.
1556      DO NOT EDIT! -->
1557 <!-- Shaarli {$exportWhat} bookmarks export on {$currentdate} -->
1558 <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=UTF-8">
1559 <TITLE>Bookmarks</TITLE>
1560 <H1>Bookmarks</H1>
1561 HTML;
1562         foreach($LINKSDB as $link)
1563         {
1564             if ($exportWhat=='all' ||
1565                ($exportWhat=='private' && $link['private']!=0) ||
1566                ($exportWhat=='public' && $link['private']==0))
1567             {
1568                 echo '<DT><A HREF="'.htmlspecialchars($link['url']).'" ADD_DATE="'.linkdate2timestamp($link['linkdate']).'" PRIVATE="'.$link['private'].'"';
1569                 if ($link['tags']!='') echo ' TAGS="'.htmlspecialchars(str_replace(' ',',',$link['tags'])).'"';
1570                 echo '>'.htmlspecialchars($link['title'])."</A>\n";
1571                 if ($link['description']!='') echo '<DD>'.htmlspecialchars($link['description'])."\n";
1572             }
1573         }
1574                 exit;
1575     }
1576
1577     // -------- User is uploading a file for import
1578     if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=upload'))
1579     {
1580         // If file is too big, some form field may be missing.
1581         if (!isset($_POST['token']) || (!isset($_FILES)) || (isset($_FILES['filetoupload']['size']) && $_FILES['filetoupload']['size']==0))
1582         {
1583             $returnurl = ( empty($_SERVER['HTTP_REFERER']) ? '?' : $_SERVER['HTTP_REFERER'] );
1584             echo '<script language="JavaScript">alert("The file you are trying to upload is probably bigger than what this webserver can accept ('.getMaxFileSize().' bytes). Please upload in smaller chunks.");document.location=\''.htmlspecialchars($returnurl).'\';</script>';
1585             exit;
1586         }
1587         if (!tokenOk($_POST['token'])) die('Wrong token.');
1588         importFile();
1589         exit;
1590     }
1591
1592     // -------- Show upload/import dialog:
1593     if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=import'))
1594     {
1595         $PAGE = new pageBuilder;
1596         $PAGE->assign('linkcount',count($LINKSDB));
1597         $PAGE->assign('token',getToken());
1598         $PAGE->assign('maxfilesize',getMaxFileSize());
1599         $PAGE->renderPage('import');
1600         exit;
1601     }
1602
1603     // -------- Otherwise, simply display search form and links:
1604     $PAGE = new pageBuilder;
1605     $PAGE->assign('linkcount',count($LINKSDB));
1606     buildLinkList($PAGE,$LINKSDB); // Compute list of links to display
1607     $PAGE->renderPage('linklist');
1608     exit;
1609 }
1610
1611 // -----------------------------------------------------------------------------------------------
1612 // Process the import file form.
1613 function importFile()
1614 {
1615     if (!(isLoggedIn() || $GLOBALS['config']['OPEN_SHAARLI'])) { die('Not allowed.'); }
1616     $LINKSDB=new linkdb(isLoggedIn() || $GLOBALS['config']['OPEN_SHAARLI']);  // Read links from database (and filter private links if used it not logged in).
1617     $filename=$_FILES['filetoupload']['name'];
1618     $filesize=$_FILES['filetoupload']['size'];
1619     $data=file_get_contents($_FILES['filetoupload']['tmp_name']);
1620     $private = (empty($_POST['private']) ? 0 : 1); // Should the links be imported as private ?
1621     $overwrite = !empty($_POST['overwrite']) ; // Should the imported links overwrite existing ones ?
1622     $import_count=0;
1623
1624     // Sniff file type:
1625     $type='unknown';
1626     if (startsWith($data,'<!DOCTYPE NETSCAPE-Bookmark-file-1>')) $type='netscape'; // Netscape bookmark file (aka Firefox).
1627
1628     // Then import the bookmarks.
1629     if ($type=='netscape')
1630     {
1631         // This is a standard Netscape-style bookmark file.
1632         // This format is supported by all browsers (except IE, of course), also delicious, diigo and others.
1633         foreach(explode('<DT>',$data) as $html) // explode is very fast
1634         {
1635             $link = array('linkdate'=>'','title'=>'','url'=>'','description'=>'','tags'=>'','private'=>0);
1636             $d = explode('<DD>',$html);
1637             if (startswith($d[0],'<A '))
1638             {
1639                 $link['description'] = (isset($d[1]) ? html_entity_decode(trim($d[1]),ENT_QUOTES,'UTF-8') : '');  // Get description (optional)
1640                 preg_match('!<A .*?>(.*?)</A>!i',$d[0],$matches); $link['title'] = (isset($matches[1]) ? trim($matches[1]) : '');  // Get title
1641                 $link['title'] = html_entity_decode($link['title'],ENT_QUOTES,'UTF-8');
1642                 preg_match_all('! ([A-Z_]+)=\"(.*?)"!i',$html,$matches,PREG_SET_ORDER);  // Get all other attributes
1643                 $raw_add_date=0;
1644                 foreach($matches as $m)
1645                 {
1646                     $attr=$m[1]; $value=$m[2];
1647                     if ($attr=='HREF') $link['url']=html_entity_decode($value,ENT_QUOTES,'UTF-8');
1648                     elseif ($attr=='ADD_DATE') $raw_add_date=intval($value);
1649                     elseif ($attr=='PRIVATE') $link['private']=($value=='0'?0:1);
1650                     elseif ($attr=='TAGS') $link['tags']=html_entity_decode(str_replace(',',' ',$value),ENT_QUOTES,'UTF-8');
1651                 }
1652                 if ($link['url']!='')
1653                 {
1654                     if ($private==1) $link['private']=1;
1655                     $dblink = $LINKSDB->getLinkFromUrl($link['url']); // See if the link is already in database.
1656                     if ($dblink==false)
1657                     {  // Link not in database, let's import it...
1658                        if (empty($raw_add_date)) $raw_add_date=time(); // In case of shitty bookmark file with no ADD_DATE
1659
1660                        // Make sure date/time is not already used by another link.
1661                        // (Some bookmark files have several different links with the same ADD_DATE)
1662                        // We increment date by 1 second until we find a date which is not used in db.
1663                        // (so that links that have the same date/time are more or less kept grouped by date, but do not conflict.)
1664                        while (!empty($LINKSDB[date('Ymd_His',$raw_add_date)])) { $raw_add_date++; }// Yes, I know it's ugly.
1665                        $link['linkdate']=date('Ymd_His',$raw_add_date);
1666                        $LINKSDB[$link['linkdate']] = $link;
1667                        $import_count++;
1668                     }
1669                     else // link already present in database.
1670                     {
1671                         if ($overwrite)
1672                         {   // If overwrite is required, we import link data, except date/time.
1673                             $link['linkdate']=$dblink['linkdate'];
1674                             $LINKSDB[$link['linkdate']] = $link;
1675                             $import_count++;
1676                         }
1677                     }
1678
1679                 }
1680             }
1681         }
1682         $LINKSDB->savedb();
1683
1684         echo '<script language="JavaScript">alert("File '.$filename.' ('.$filesize.' bytes) was successfully processed: '.$import_count.' links imported.");document.location=\'?\';</script>';
1685     }
1686     else
1687     {
1688         echo '<script language="JavaScript">alert("File '.$filename.' ('.$filesize.' bytes) has an unknown file format. Nothing was imported.");document.location=\'?\';</script>';
1689     }
1690 }
1691
1692 // -----------------------------------------------------------------------------------------------
1693 // Template for the list of links (<div id="linklist">)
1694 // This function fills all the necessary fields in the $PAGE for the template 'linklist.html'
1695 function buildLinkList($PAGE,$LINKSDB)
1696 {
1697     // ---- Filter link database according to parameters
1698     $linksToDisplay=array();
1699     $search_type='';
1700     $search_crits='';
1701     if (isset($_GET['searchterm'])) // Fulltext search
1702     {
1703         $linksToDisplay = $LINKSDB->filterFulltext(trim($_GET['searchterm']));
1704         $search_crits=htmlspecialchars(trim($_GET['searchterm']));
1705         $search_type='fulltext';
1706     }
1707     elseif (isset($_GET['searchtags'])) // Search by tag
1708     {
1709         $linksToDisplay = $LINKSDB->filterTags(trim($_GET['searchtags']));
1710         $search_crits=explode(' ',trim($_GET['searchtags']));
1711         $search_type='tags';
1712     }
1713     elseif (isset($_SERVER['QUERY_STRING']) && preg_match('/[a-zA-Z0-9-_@]{6}(&.+?)?/',$_SERVER['QUERY_STRING'])) // Detect smallHashes in URL
1714     {
1715         $linksToDisplay = $LINKSDB->filterSmallHash(substr(trim($_SERVER["QUERY_STRING"], '/'),0,6));
1716         if (count($linksToDisplay)==0)
1717         {
1718             header($_SERVER["SERVER_PROTOCOL"]." 404 Not Found");
1719             echo '<h1>404 Not found.</h1>Oh crap. The link you are trying to reach does not exist or has been deleted.';
1720             echo '<br>You would mind <a href="?">clicking here</a> ?';
1721             exit;
1722         }
1723         $search_type='permalink';
1724     }
1725     else
1726         $linksToDisplay = $LINKSDB;  // otherwise, display without filtering.
1727
1728     // Option: Show only private links
1729     if (!empty($_SESSION['privateonly']))
1730     {
1731         $tmp = array();
1732         foreach($linksToDisplay as $linkdate=>$link)
1733         {
1734             if ($link['private']!=0) $tmp[$linkdate]=$link;
1735         }
1736         $linksToDisplay=$tmp;
1737     }
1738
1739     // ---- Handle paging.
1740     /* Can someone explain to me why you get the following error when using array_keys() on an object which implements the interface ArrayAccess ???
1741        "Warning: array_keys() expects parameter 1 to be array, object given in ... "
1742        If my class implements ArrayAccess, why won't array_keys() accept it ?  ( $keys=array_keys($linksToDisplay); )
1743     */
1744     $keys=array(); foreach($linksToDisplay as $key=>$value) { $keys[]=$key; } // Stupid and ugly. Thanks php.
1745
1746     // If there is only a single link, we change on-the-fly the title of the page.
1747     if (count($linksToDisplay)==1) $GLOBALS['pagetitle'] = $linksToDisplay[$keys[0]]['title'].' - '.$GLOBALS['title'];
1748
1749     // Select articles according to paging.
1750     $pagecount = ceil(count($keys)/$_SESSION['LINKS_PER_PAGE']);
1751     $pagecount = ($pagecount==0 ? 1 : $pagecount);
1752     $page=( empty($_GET['page']) ? 1 : intval($_GET['page']));
1753     $page = ( $page<1 ? 1 : $page );
1754     $page = ( $page>$pagecount ? $pagecount : $page );
1755     $i = ($page-1)*$_SESSION['LINKS_PER_PAGE']; // Start index.
1756     $end = $i+$_SESSION['LINKS_PER_PAGE'];
1757     $linkDisp=array(); // Links to display
1758     while ($i<$end && $i<count($keys))
1759     {
1760         $link = $linksToDisplay[$keys[$i]];
1761         $link['description']=nl2br(keepMultipleSpaces(text2clickable(htmlspecialchars($link['description']))));
1762         $title=$link['title'];
1763         $classLi =  $i%2!=0 ? '' : 'publicLinkHightLight';
1764         $link['class'] = ($link['private']==0 ? $classLi : 'private');
1765         $link['localdate']=linkdate2locale($link['linkdate']);
1766         $taglist = explode(' ',$link['tags']);
1767         uasort($taglist, 'strcasecmp');
1768         $link['taglist']=$taglist;
1769         $linkDisp[$keys[$i]] = $link;
1770         $i++;
1771     }
1772
1773     // Compute paging navigation
1774     $searchterm= ( empty($_GET['searchterm']) ? '' : '&searchterm='.$_GET['searchterm'] );
1775     $searchtags= ( empty($_GET['searchtags']) ? '' : '&searchtags='.$_GET['searchtags'] );
1776     $paging='';
1777     $previous_page_url=''; if ($i!=count($keys)) $previous_page_url='?page='.($page+1).$searchterm.$searchtags;
1778     $next_page_url='';if ($page>1) $next_page_url='?page='.($page-1).$searchterm.$searchtags;
1779
1780     $token = ''; if (isLoggedIn()) $token=getToken();
1781
1782     // Fill all template fields.
1783     $PAGE->assign('linkcount',count($LINKSDB));
1784     $PAGE->assign('previous_page_url',$previous_page_url);
1785     $PAGE->assign('next_page_url',$next_page_url);
1786     $PAGE->assign('page_current',$page);
1787     $PAGE->assign('page_max',$pagecount);
1788     $PAGE->assign('result_count',count($linksToDisplay));
1789     $PAGE->assign('search_type',$search_type);
1790     $PAGE->assign('search_crits',$search_crits);
1791     $PAGE->assign('redirector',empty($GLOBALS['redirector']) ? '' : $GLOBALS['redirector']); // optional redirector URL
1792     $PAGE->assign('token',$token);
1793     $PAGE->assign('links',$linkDisp);
1794     return;
1795 }
1796
1797 // Compute the thumbnail for a link.
1798 //
1799 // with a link to the original URL.
1800 // Understands various services (youtube.com...)
1801 // Input: $url = url for which the thumbnail must be found.
1802 //        $href = if provided, this URL will be followed instead of $url
1803 // Returns an associative array with thumbnail attributes (src,href,width,height,style,alt)
1804 // Some of them may be missing.
1805 // Return an empty array if no thumbnail available.
1806 function computeThumbnail($url,$href=false)
1807 {
1808     if (!$GLOBALS['config']['ENABLE_THUMBNAILS']) return array();
1809     if ($href==false) $href=$url;
1810
1811     // For most hosts, the URL of the thumbnail can be easily deduced from the URL of the link.
1812     // (eg. http://www.youtube.com/watch?v=spVypYk4kto --->  http://img.youtube.com/vi/spVypYk4kto/default.jpg )
1813     //                                     ^^^^^^^^^^^                                 ^^^^^^^^^^^
1814     $domain = parse_url($url,PHP_URL_HOST);
1815     if ($domain=='youtube.com' || $domain=='www.youtube.com')
1816     {
1817         parse_str(parse_url($url,PHP_URL_QUERY), $params); // Extract video ID and get thumbnail
1818         if (!empty($params['v'])) return array('src'=>'http://img.youtube.com/vi/'.$params['v'].'/default.jpg',
1819                                                'href'=>$href,'width'=>'120','height'=>'90','alt'=>'YouTube thumbnail');
1820     }
1821     if ($domain=='youtu.be') // Youtube short links
1822     {
1823         $path = parse_url($url,PHP_URL_PATH);
1824         return array('src'=>'http://img.youtube.com/vi'.$path.'/default.jpg',
1825                      'href'=>$href,'width'=>'120','height'=>'90','alt'=>'YouTube thumbnail');
1826     }
1827     if ($domain=='pix.toile-libre.org') // pix.toile-libre.org image hosting
1828     {
1829         parse_str(parse_url($url,PHP_URL_QUERY), $params); // Extract image filename.
1830         if (!empty($params) && !empty($params['img'])) return array('src'=>'http://pix.toile-libre.org/upload/thumb/'.urlencode($params['img']),
1831                                                                     'href'=>$href,'style'=>'max-width:120px; max-height:150px','alt'=>'pix.toile-libre.org thumbnail');
1832     }
1833
1834     if ($domain=='imgur.com')
1835     {
1836         $path = parse_url($url,PHP_URL_PATH);
1837         if (startsWith($path,'/a/')) return array(); // Thumbnails for albums are not available.
1838         if (startsWith($path,'/r/')) return array('src'=>'http://i.imgur.com/'.basename($path).'s.jpg',
1839                                                   'href'=>$href,'width'=>'90','height'=>'90','alt'=>'imgur.com thumbnail');
1840         if (startsWith($path,'/gallery/')) return array('src'=>'http://i.imgur.com'.substr($path,8).'s.jpg',
1841                                                         'href'=>$href,'width'=>'90','height'=>'90','alt'=>'imgur.com thumbnail');
1842
1843         if (substr_count($path,'/')==1) return array('src'=>'http://i.imgur.com/'.substr($path,1).'s.jpg',
1844                                                      'href'=>$href,'width'=>'90','height'=>'90','alt'=>'imgur.com thumbnail');
1845     }
1846     if ($domain=='i.imgur.com')
1847     {
1848         $pi = pathinfo(parse_url($url,PHP_URL_PATH));
1849         if (!empty($pi['filename'])) return array('src'=>'http://i.imgur.com/'.$pi['filename'].'s.jpg',
1850                                                   'href'=>$href,'width'=>'90','height'=>'90','alt'=>'imgur.com thumbnail');
1851     }
1852     if ($domain=='dailymotion.com' || $domain=='www.dailymotion.com')
1853     {
1854         if (strpos($url,'dailymotion.com/video/')!==false)
1855         {
1856             $thumburl=str_replace('dailymotion.com/video/','dailymotion.com/thumbnail/video/',$url);
1857             return array('src'=>$thumburl,
1858                          'href'=>$href,'width'=>'120','style'=>'height:auto;','alt'=>'DailyMotion thumbnail');
1859         }
1860     }
1861     if (endsWith($domain,'.imageshack.us'))
1862     {
1863         $ext=strtolower(pathinfo($url,PATHINFO_EXTENSION));
1864         if ($ext=='jpg' || $ext=='jpeg' || $ext=='png' || $ext=='gif')
1865         {
1866             $thumburl = substr($url,0,strlen($url)-strlen($ext)).'th.'.$ext;
1867             return array('src'=>$thumburl,
1868                          'href'=>$href,'width'=>'120','style'=>'height:auto;','alt'=>'imageshack.us thumbnail');
1869         }
1870     }
1871
1872     // Some other hosts are SLOW AS HELL and usually require an extra HTTP request to get the thumbnail URL.
1873     // So we deport the thumbnail generation in order not to slow down page generation
1874     // (and we also cache the thumbnail)
1875
1876     if (!$GLOBALS['config']['ENABLE_LOCALCACHE']) return array(); // If local cache is disabled, no thumbnails for services which require the use a local cache.
1877
1878     if ($domain=='flickr.com' || endsWith($domain,'.flickr.com')
1879         || $domain=='vimeo.com'
1880         || $domain=='ted.com' || endsWith($domain,'.ted.com')
1881         || $domain=='xkcd.com' || endsWith($domain,'.xkcd.com')
1882     )
1883     {
1884         if ($domain=='vimeo.com')
1885         {   // Make sure this vimeo url points to a video (/xxx... where xxx is numeric)
1886             $path = parse_url($url,PHP_URL_PATH);
1887             if (!preg_match('!/\d+.+?!',$path)) return array(); // This is not a single video URL.
1888         }
1889         if ($domain=='xkcd.com' || endsWith($domain,'.xkcd.com'))
1890         {   // Make sure this url points to a single comic (/xxx... where xxx is numeric)
1891             $path = parse_url($url,PHP_URL_PATH);
1892             if (!preg_match('!/\d+.+?!',$path)) return array();
1893         }
1894         if ($domain=='ted.com' || endsWith($domain,'.ted.com'))
1895         {   // Make sure this TED url points to a video (/talks/...)
1896             $path = parse_url($url,PHP_URL_PATH);
1897             if ("/talks/" !== substr($path,0,7)) return array(); // This is not a single video URL.
1898         }
1899         $sign = hash_hmac('sha256', $url, $GLOBALS['salt']); // We use the salt to sign data (it's random, secret, and specific to each installation)
1900         return array('src'=>indexUrl().'?do=genthumbnail&hmac='.htmlspecialchars($sign).'&url='.urlencode($url),
1901                      'href'=>$href,'width'=>'120','style'=>'height:auto;','alt'=>'thumbnail');
1902     }
1903
1904     // For all other, we try to make a thumbnail of links ending with .jpg/jpeg/png/gif
1905     // Technically speaking, we should download ALL links and check their Content-Type to see if they are images.
1906     // But using the extension will do.
1907     $ext=strtolower(pathinfo($url,PATHINFO_EXTENSION));
1908     if ($ext=='jpg' || $ext=='jpeg' || $ext=='png' || $ext=='gif')
1909     {
1910         $sign = hash_hmac('sha256', $url, $GLOBALS['salt']); // We use the salt to sign data (it's random, secret, and specific to each installation)
1911         return array('src'=>indexUrl().'?do=genthumbnail&hmac='.htmlspecialchars($sign).'&url='.urlencode($url),
1912                      'href'=>$href,'width'=>'120','style'=>'height:auto;','alt'=>'thumbnail');
1913     }
1914     return array(); // No thumbnail.
1915
1916 }
1917
1918
1919 // Returns the HTML code to display a thumbnail for a link
1920 // with a link to the original URL.
1921 // Understands various services (youtube.com...)
1922 // Input: $url = url for which the thumbnail must be found.
1923 //        $href = if provided, this URL will be followed instead of $url
1924 // Returns '' if no thumbnail available.
1925 function thumbnail($url,$href=false)
1926 {
1927     $t = computeThumbnail($url,$href);
1928     if (count($t)==0) return ''; // Empty array = no thumbnail for this URL.
1929
1930     $html='<a href="'.htmlspecialchars($t['href']).'"><img src="'.htmlspecialchars($t['src']).'"';
1931     if (!empty($t['width']))  $html.=' width="'.htmlspecialchars($t['width']).'"';
1932     if (!empty($t['height'])) $html.=' height="'.htmlspecialchars($t['height']).'"';
1933     if (!empty($t['style']))  $html.=' style="'.htmlspecialchars($t['style']).'"';
1934     if (!empty($t['alt']))    $html.=' alt="'.htmlspecialchars($t['alt']).'"';
1935     $html.='></a>';
1936     return $html;
1937 }
1938
1939
1940 // Returns the HTML code to display a thumbnail for a link
1941 // for the picture wall (using lazy image loading)
1942 // Understands various services (youtube.com...)
1943 // Input: $url = url for which the thumbnail must be found.
1944 //        $href = if provided, this URL will be followed instead of $url
1945 // Returns '' if no thumbnail available.
1946 function lazyThumbnail($url,$href=false)
1947 {
1948     $t = computeThumbnail($url,$href);
1949     if (count($t)==0) return ''; // Empty array = no thumbnail for this URL.
1950
1951     $html='<a href="'.htmlspecialchars($t['href']).'">';
1952
1953     // Lazy image (only loaded by javascript when in the viewport).
1954     $html.='<img class="lazyimage" src="#" data-original="'.htmlspecialchars($t['src']).'"';
1955     if (!empty($t['width']))  $html.=' width="'.htmlspecialchars($t['width']).'"';
1956     if (!empty($t['height'])) $html.=' height="'.htmlspecialchars($t['height']).'"';
1957     if (!empty($t['style']))  $html.=' style="'.htmlspecialchars($t['style']).'"';
1958     if (!empty($t['alt']))    $html.=' alt="'.htmlspecialchars($t['alt']).'"';
1959     $html.='>';
1960
1961     // No-javascript fallback:
1962     $html.='<noscript><img src="'.htmlspecialchars($t['src']).'"';
1963     if (!empty($t['width']))  $html.=' width="'.htmlspecialchars($t['width']).'"';
1964     if (!empty($t['height'])) $html.=' height="'.htmlspecialchars($t['height']).'"';
1965     if (!empty($t['style']))  $html.=' style="'.htmlspecialchars($t['style']).'"';
1966     if (!empty($t['alt']))    $html.=' alt="'.htmlspecialchars($t['alt']).'"';
1967     $html.='></noscript></a>';
1968
1969     return $html;
1970 }
1971
1972
1973 // -----------------------------------------------------------------------------------------------
1974 // Installation
1975 // This function should NEVER be called if the file data/config.php exists.
1976 function install()
1977 {
1978     // On free.fr host, make sure the /sessions directory exists, otherwise login will not work.
1979     if (endsWith($_SERVER['SERVER_NAME'],'.free.fr') && !is_dir($_SERVER['DOCUMENT_ROOT'].'/sessions')) mkdir($_SERVER['DOCUMENT_ROOT'].'/sessions',0705);
1980
1981
1982     // This part makes sure sessions works correctly.
1983     // (Because on some hosts, session.save_path may not be set correctly,
1984     // or we may not have write access to it.)
1985     if (isset($_GET['test_session']) && ( !isset($_SESSION) || !isset($_SESSION['session_tested']) || $_SESSION['session_tested']!='Working'))
1986     {   // Step 2: Check if data in session is correct.
1987         echo '<pre>Sessions do not seem to work correctly on your server.<br>';
1988         echo 'Make sure the variable session.save_path is set correctly in your php config, and that you have write access to it.<br>';
1989         echo 'It currently points to '.session_save_path().'<br><br><a href="?">Click to try again.</a></pre>';
1990         die;
1991     }
1992     if (!isset($_SESSION['session_tested']))
1993     {   // Step 1 : Try to store data in session and reload page.
1994         $_SESSION['session_tested'] = 'Working';  // Try to set a variable in session.
1995         header('Location: '.indexUrl().'?test_session');  // Redirect to check stored data.
1996     }
1997     if (isset($_GET['test_session']))
1998     {   // Step 3: Sessions are ok. Remove test parameter from URL.
1999         header('Location: '.indexUrl());
2000     }
2001
2002
2003     if (!empty($_POST['setlogin']) && !empty($_POST['setpassword']))
2004     {
2005         $tz = 'UTC';
2006         if (!empty($_POST['continent']) && !empty($_POST['city']))
2007             if (isTZvalid($_POST['continent'],$_POST['city']))
2008                 $tz = $_POST['continent'].'/'.$_POST['city'];
2009         $GLOBALS['timezone'] = $tz;
2010         // Everything is ok, let's create config file.
2011         $GLOBALS['login'] = $_POST['setlogin'];
2012         $GLOBALS['salt'] = sha1(uniqid('',true).'_'.mt_rand()); // Salt renders rainbow-tables attacks useless.
2013         $GLOBALS['hash'] = sha1($_POST['setpassword'].$GLOBALS['login'].$GLOBALS['salt']);
2014         $GLOBALS['title'] = (empty($_POST['title']) ? 'Shared links on '.htmlspecialchars(indexUrl()) : $_POST['title'] );
2015         writeConfig();
2016         echo '<script language="JavaScript">alert("Shaarli is now configured. Please enter your login/password and start shaaring your links !");document.location=\'?do=login\';</script>';
2017         exit;
2018     }
2019
2020     // Display config form:
2021     list($timezone_form,$timezone_js) = templateTZform();
2022     $timezone_html=''; if ($timezone_form!='') $timezone_html='<tr><td valign="top"><b>Timezone:</b></td><td>'.$timezone_form.'</td></tr>';
2023
2024     $PAGE = new pageBuilder;
2025     $PAGE->assign('timezone_html',$timezone_html);
2026     $PAGE->assign('timezone_js',$timezone_js);
2027     $PAGE->renderPage('install');
2028     exit;
2029 }
2030
2031 // Generates the timezone selection form and javascript.
2032 // Input: (optional) current timezone (can be 'UTC/UTC'). It will be pre-selected.
2033 // Output: array(html,js)
2034 // Example: list($htmlform,$js) = templateTZform('Europe/Paris');  // Europe/Paris pre-selected.
2035 // Returns array('','') if server does not support timezones list. (eg. php 5.1 on free.fr)
2036 function templateTZform($ptz=false)
2037 {
2038     if (function_exists('timezone_identifiers_list')) // because of old php version (5.1) which can be found on free.fr
2039     {
2040         // Try to split the provided timezone.
2041         if ($ptz==false) { $l=timezone_identifiers_list(); $ptz=$l[0]; }
2042         $spos=strpos($ptz,'/'); $pcontinent=substr($ptz,0,$spos); $pcity=substr($ptz,$spos+1);
2043
2044         // Display config form:
2045         $timezone_form = '';
2046         $timezone_js = '';
2047         // The list is in the forme "Europe/Paris", "America/Argentina/Buenos_Aires"...
2048         // We split the list in continents/cities.
2049         $continents = array();
2050         $cities = array();
2051         foreach(timezone_identifiers_list() as $tz)
2052         {
2053             if ($tz=='UTC') $tz='UTC/UTC';
2054             $spos = strpos($tz,'/');
2055             if ($spos!==false)
2056             {
2057                 $continent=substr($tz,0,$spos); $city=substr($tz,$spos+1);
2058                 $continents[$continent]=1;
2059                 if (!isset($cities[$continent])) $cities[$continent]='';
2060                 $cities[$continent].='<option value="'.$city.'"'.($pcity==$city?'selected':'').'>'.$city.'</option>';
2061             }
2062         }
2063         $continents_html = '';
2064         $continents = array_keys($continents);
2065         foreach($continents as $continent)
2066             $continents_html.='<option  value="'.$continent.'"'.($pcontinent==$continent?'selected':'').'>'.$continent.'</option>';
2067         $cities_html = $cities[$pcontinent];
2068         $timezone_form = "Continent: <select name=\"continent\" id=\"continent\" onChange=\"onChangecontinent();\">${continents_html}</select><br /><br />";
2069         $timezone_form .= "City: <select name=\"city\" id=\"city\">${cities[$pcontinent]}</select><br /><br />";
2070         $timezone_js = "<script language=\"JavaScript\">";
2071         $timezone_js .= "function onChangecontinent(){document.getElementById(\"city\").innerHTML = citiescontinent[document.getElementById(\"continent\").value];}";
2072         $timezone_js .= "var citiescontinent = ".json_encode($cities).";" ;
2073         $timezone_js .= "</script>" ;
2074         return array($timezone_form,$timezone_js);
2075     }
2076     return array('','');
2077 }
2078
2079 // Tells if a timezone is valid or not.
2080 // If not valid, returns false.
2081 // If system does not support timezone list, returns false.
2082 function isTZvalid($continent,$city)
2083 {
2084     $tz = $continent.'/'.$city;
2085     if (function_exists('timezone_identifiers_list')) // because of old php version (5.1) which can be found on free.fr
2086     {
2087         if (in_array($tz, timezone_identifiers_list())) // it's a valid timezone ?
2088                     return true;
2089     }
2090     return false;
2091 }
2092
2093
2094 // Webservices (for use with jQuery/jQueryUI)
2095 // eg.  index.php?ws=tags&term=minecr
2096 function processWS()
2097 {
2098     if (empty($_GET['ws']) || empty($_GET['term'])) return;
2099     $term = $_GET['term'];
2100     $LINKSDB=new linkdb(isLoggedIn() || $GLOBALS['config']['OPEN_SHAARLI']);  // Read links from database (and filter private links if used it not logged in).
2101     header('Content-Type: application/json; charset=utf-8');
2102
2103     // Search in tags (case insentitive, cumulative search)
2104     if ($_GET['ws']=='tags')
2105     {
2106         $tags=explode(' ',str_replace(',',' ',$term)); $last = array_pop($tags); // Get the last term ("a b c d" ==> "a b c", "d")
2107         $addtags=''; if ($tags) $addtags=implode(' ',$tags).' '; // We will pre-pend previous tags
2108         $suggested=array();
2109         /* To speed up things, we store list of tags in session */
2110         if (empty($_SESSION['tags'])) $_SESSION['tags'] = $LINKSDB->allTags();
2111         foreach($_SESSION['tags'] as $key=>$value)
2112         {
2113             if (startsWith($key,$last,$case=false) && !in_array($key,$tags)) $suggested[$addtags.$key.' ']=0;
2114         }
2115         echo json_encode(array_keys($suggested));
2116         exit;
2117     }
2118
2119     // Search a single tag (case sentitive, single tag search)
2120     if ($_GET['ws']=='singletag')
2121     {
2122         /* To speed up things, we store list of tags in session */
2123         if (empty($_SESSION['tags'])) $_SESSION['tags'] = $LINKSDB->allTags();
2124         foreach($_SESSION['tags'] as $key=>$value)
2125         {
2126             if (startsWith($key,$term,$case=true)) $suggested[$key]=0;
2127         }
2128         echo json_encode(array_keys($suggested));
2129         exit;
2130     }
2131 }
2132
2133 // Re-write configuration file according to globals.
2134 // Requires some $GLOBALS to be set (login,hash,salt,title).
2135 // If the config file cannot be saved, an error message is dislayed and the user is redirected to "Tools" menu.
2136 // (otherwise, the function simply returns.)
2137 function writeConfig()
2138 {
2139     if (is_file($GLOBALS['config']['CONFIG_FILE']) && !isLoggedIn()) die('You are not authorized to alter config.'); // Only logged in user can alter config.
2140     if (empty($GLOBALS['redirector'])) $GLOBALS['redirector']='';
2141     if (empty($GLOBALS['disablesessionprotection'])) $GLOBALS['disablesessionprotection']=false;
2142     $config='<?php $GLOBALS[\'login\']='.var_export($GLOBALS['login'],true).'; $GLOBALS[\'hash\']='.var_export($GLOBALS['hash'],true).'; $GLOBALS[\'salt\']='.var_export($GLOBALS['salt'],true).'; ';
2143     $config .='$GLOBALS[\'timezone\']='.var_export($GLOBALS['timezone'],true).'; date_default_timezone_set('.var_export($GLOBALS['timezone'],true).'); $GLOBALS[\'title\']='.var_export($GLOBALS['title'],true).';';
2144     $config .= '$GLOBALS[\'redirector\']='.var_export($GLOBALS['redirector'],true).'; ';
2145     $config .= '$GLOBALS[\'disablesessionprotection\']='.var_export($GLOBALS['disablesessionprotection'],true).'; ';
2146     $config .= ' ?>';
2147     if (!file_put_contents($GLOBALS['config']['CONFIG_FILE'],$config) || strcmp(file_get_contents($GLOBALS['config']['CONFIG_FILE']),$config)!=0)
2148     {
2149         echo '<script language="JavaScript">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>';
2150         exit;
2151     }
2152 }
2153
2154 /* Because some f*cking services like Flickr require an extra HTTP request to get the thumbnail URL,
2155    I have deported the thumbnail URL code generation here, otherwise this would slow down page generation.
2156    The following function takes the URL a link (eg. a flickr page) and return the proper thumbnail.
2157    This function is called by passing the url:
2158    http://mywebsite.com/shaarli/?do=genthumbnail&hmac=[HMAC]&url=[URL]
2159    [URL] is the URL of the link (eg. a flickr page)
2160    [HMAC] is the signature for the [URL] (so that these URL cannot be forged).
2161    The function below will fetch the image from the webservice and store it in the cache.
2162 */
2163 function genThumbnail()
2164 {
2165     // Make sure the parameters in the URL were generated by us.
2166     $sign = hash_hmac('sha256', $_GET['url'], $GLOBALS['salt']);
2167     if ($sign!=$_GET['hmac']) die('Naughty boy !');
2168
2169     // Let's see if we don't already have the image for this URL in the cache.
2170     $thumbname=hash('sha1',$_GET['url']).'.jpg';
2171     if (is_file($GLOBALS['config']['CACHEDIR'].'/'.$thumbname))
2172     {   // We have the thumbnail, just serve it:
2173         header('Content-Type: image/jpeg');
2174         echo file_get_contents($GLOBALS['config']['CACHEDIR'].'/'.$thumbname);
2175         return;
2176     }
2177     // We may also serve a blank image (if service did not respond)
2178     $blankname=hash('sha1',$_GET['url']).'.gif';
2179     if (is_file($GLOBALS['config']['CACHEDIR'].'/'.$blankname))
2180     {
2181         header('Content-Type: image/gif');
2182         echo file_get_contents($GLOBALS['config']['CACHEDIR'].'/'.$blankname);
2183         return;
2184     }
2185
2186     // Otherwise, generate the thumbnail.
2187     $url = $_GET['url'];
2188     $domain = parse_url($url,PHP_URL_HOST);
2189
2190     if ($domain=='flickr.com' || endsWith($domain,'.flickr.com'))
2191     {
2192         // Crude replacement to handle new Flickr domain policy (They prefer www. now)
2193         $url = str_replace('http://flickr.com/','http://www.flickr.com/',$url);
2194
2195         // Is this a link to an image, or to a flickr page ?
2196         $imageurl='';
2197         if (endswith(parse_url($url,PHP_URL_PATH),'.jpg'))
2198         {  // This is a direct link to an image. eg. http://farm1.staticflickr.com/5/5921913_ac83ed27bd_o.jpg
2199             preg_match('!(http://farm\d+\.staticflickr\.com/\d+/\d+_\w+_)\w.jpg!',$url,$matches);
2200             if (!empty($matches[1])) $imageurl=$matches[1].'m.jpg';
2201         }
2202         else // this is a flickr page (html)
2203         {
2204             list($httpstatus,$headers,$data) = getHTTP($url,20); // Get the flickr html page.
2205             if (strpos($httpstatus,'200 OK')!==false)
2206             {
2207                 // Flickr now nicely provides the URL of the thumbnail in each flickr page.
2208                 preg_match('!<link rel=\"image_src\" href=\"(.+?)\"!',$data,$matches);
2209                 if (!empty($matches[1])) $imageurl=$matches[1];
2210
2211                 // In albums (and some other pages), the link rel="image_src" is not provided,
2212                 // but flickr provides:
2213                 // <meta property="og:image" content="http://farm4.staticflickr.com/3398/3239339068_25d13535ff_z.jpg" />
2214                 if ($imageurl=='')
2215                 {
2216                     preg_match('!<meta property=\"og:image\" content=\"(.+?)\"!',$data,$matches);
2217                     if (!empty($matches[1])) $imageurl=$matches[1];
2218                 }
2219             }
2220         }
2221
2222         if ($imageurl!='')
2223         {   // Let's download the image.
2224             list($httpstatus,$headers,$data) = getHTTP($imageurl,10); // Image is 240x120, so 10 seconds to download should be enough.
2225             if (strpos($httpstatus,'200 OK')!==false)
2226             {
2227                 file_put_contents($GLOBALS['config']['CACHEDIR'].'/'.$thumbname,$data); // Save image to cache.
2228                 header('Content-Type: image/jpeg');
2229                 echo $data;
2230                 return;
2231             }
2232         }
2233     }
2234
2235     elseif ($domain=='vimeo.com' )
2236     {
2237         // This is more complex: we have to perform a HTTP request, then parse the result.
2238         // Maybe we should deport this to javascript ? Example: http://stackoverflow.com/questions/1361149/get-img-thumbnails-from-vimeo/4285098#4285098
2239         $vid = substr(parse_url($url,PHP_URL_PATH),1);
2240         list($httpstatus,$headers,$data) = getHTTP('http://vimeo.com/api/v2/video/'.htmlspecialchars($vid).'.php',5);
2241         if (strpos($httpstatus,'200 OK')!==false)
2242         {
2243             $t = unserialize($data);
2244             $imageurl = $t[0]['thumbnail_medium'];
2245             // Then we download the image and serve it to our client.
2246             list($httpstatus,$headers,$data) = getHTTP($imageurl,10);
2247             if (strpos($httpstatus,'200 OK')!==false)
2248             {
2249                 file_put_contents($GLOBALS['config']['CACHEDIR'].'/'.$thumbname,$data); // Save image to cache.
2250                 header('Content-Type: image/jpeg');
2251                 echo $data;
2252                 return;
2253             }
2254         }
2255     }
2256
2257     elseif ($domain=='ted.com' || endsWith($domain,'.ted.com'))
2258     {
2259         // The thumbnail for TED talks is located in the <link rel="image_src" [...]> tag on that page
2260         // http://www.ted.com/talks/mikko_hypponen_fighting_viruses_defending_the_net.html
2261         // <link rel="image_src" href="http://images.ted.com/images/ted/28bced335898ba54d4441809c5b1112ffaf36781_389x292.jpg" />
2262         list($httpstatus,$headers,$data) = getHTTP($url,5);
2263         if (strpos($httpstatus,'200 OK')!==false)
2264         {
2265             // Extract the link to the thumbnail
2266             preg_match('!link rel="image_src" href="(http://images.ted.com/images/ted/.+_\d+x\d+\.jpg)"!',$data,$matches);
2267             if (!empty($matches[1]))
2268             {   // Let's download the image.
2269                 $imageurl=$matches[1];
2270                 list($httpstatus,$headers,$data) = getHTTP($imageurl,20); // No control on image size, so wait long enough.
2271                 if (strpos($httpstatus,'200 OK')!==false)
2272                 {
2273                     $filepath=$GLOBALS['config']['CACHEDIR'].'/'.$thumbname;
2274                     file_put_contents($filepath,$data); // Save image to cache.
2275                     if (resizeImage($filepath))
2276                     {
2277                         header('Content-Type: image/jpeg');
2278                         echo file_get_contents($filepath);
2279                         return;
2280                     }
2281                 }
2282             }
2283         }
2284     }
2285
2286     elseif ($domain=='xkcd.com' || endsWith($domain,'.xkcd.com'))
2287     {
2288         // There is no thumbnail available for xkcd comics, so download the whole image and resize it.
2289         // http://xkcd.com/327/
2290         // <img src="http://imgs.xkcd.com/comics/exploits_of_a_mom.png" title="<BLABLA>" alt="<BLABLA>" />
2291         list($httpstatus,$headers,$data) = getHTTP($url,5);
2292         if (strpos($httpstatus,'200 OK')!==false)
2293         {
2294             // Extract the link to the thumbnail
2295             preg_match('!<img src="(http://imgs.xkcd.com/comics/.*)" title="[^s]!',$data,$matches);
2296             if (!empty($matches[1]))
2297             {   // Let's download the image.
2298                 $imageurl=$matches[1];
2299                 list($httpstatus,$headers,$data) = getHTTP($imageurl,20); // No control on image size, so wait long enough.
2300                 if (strpos($httpstatus,'200 OK')!==false)
2301                 {
2302                     $filepath=$GLOBALS['config']['CACHEDIR'].'/'.$thumbname;
2303                     file_put_contents($filepath,$data); // Save image to cache.
2304                     if (resizeImage($filepath))
2305                     {
2306                         header('Content-Type: image/jpeg');
2307                         echo file_get_contents($filepath);
2308                         return;
2309                     }
2310                 }
2311             }
2312         }
2313     }
2314
2315     else
2316     {
2317         // For all other domains, we try to download the image and make a thumbnail.
2318         list($httpstatus,$headers,$data) = getHTTP($url,30);  // We allow 30 seconds max to download (and downloads are limited to 4 Mb)
2319         if (strpos($httpstatus,'200 OK')!==false)
2320         {
2321             $filepath=$GLOBALS['config']['CACHEDIR'].'/'.$thumbname;
2322             file_put_contents($filepath,$data); // Save image to cache.
2323             if (resizeImage($filepath))
2324             {
2325                 header('Content-Type: image/jpeg');
2326                 echo file_get_contents($filepath);
2327                 return;
2328             }
2329         }
2330     }
2331
2332
2333     // Otherwise, return an empty image (8x8 transparent gif)
2334     $blankgif = base64_decode('R0lGODlhCAAIAIAAAP///////yH5BAEKAAEALAAAAAAIAAgAAAIHjI+py+1dAAA7');
2335     file_put_contents($GLOBALS['config']['CACHEDIR'].'/'.$blankname,$blankgif); // Also put something in cache so that this URL is not requested twice.
2336     header('Content-Type: image/gif');
2337     echo $blankgif;
2338 }
2339
2340 // Make a thumbnail of the image (to width: 120 pixels)
2341 // Returns true if success, false otherwise.
2342 function resizeImage($filepath)
2343 {
2344     if (!function_exists('imagecreatefromjpeg')) return false; // GD not present: no thumbnail possible.
2345
2346     // Trick: some stupid people rename GIF as JPEG... or else.
2347     // So we really try to open each image type whatever the extension is.
2348     $header=file_get_contents($filepath,false,NULL,0,256); // Read first 256 bytes and try to sniff file type.
2349     $im=false;
2350     $i=strpos($header,'GIF8'); if (($i!==false) && ($i==0)) $im = imagecreatefromgif($filepath); // Well this is crude, but it should be enough.
2351     $i=strpos($header,'PNG'); if (($i!==false) && ($i==1)) $im = imagecreatefrompng($filepath);
2352     $i=strpos($header,'JFIF'); if ($i!==false) $im = imagecreatefromjpeg($filepath);
2353     if (!$im) return false;  // Unable to open image (corrupted or not an image)
2354     $w = imagesx($im);
2355     $h = imagesy($im);
2356     $ystart = 0; $yheight=$h;
2357     if ($h>$w) { $ystart= ($h/2)-($w/2); $yheight=$w/2; }
2358     $nw = 120;   // Desired width
2359     $nh = min(floor(($h*$nw)/$w),120); // Compute new width/height, but maximum 120 pixels height.
2360     // Resize image:
2361     $im2 = imagecreatetruecolor($nw,$nh);
2362     imagecopyresampled($im2, $im, 0, 0, 0, $ystart, $nw, $nh, $w, $yheight);
2363     imageinterlace($im2,true); // For progressive JPEG.
2364     $tempname=$filepath.'_TEMP.jpg';
2365     imagejpeg($im2, $tempname, 90);
2366     imagedestroy($im);
2367     imagedestroy($im2);
2368     unlink($filepath);
2369     rename($tempname,$filepath);  // Overwrite original picture with thumbnail.
2370     return true;
2371 }
2372
2373 // Invalidate caches when the database is changed or the user logs out.
2374 // (eg. tags cache).
2375 function invalidateCaches()
2376 {
2377     unset($_SESSION['tags']);  // Purge cache attached to session.
2378     pageCache::purgeCache();   // Purge page cache shared by sessions.
2379 }
2380
2381 if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=genthumbnail')) { genThumbnail(); exit; }  // Thumbnail generation/cache does not need the link database.
2382 if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=rss')) { showRSS(); exit; }
2383 if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=atom')) { showATOM(); exit; }
2384 if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=dailyrss')) { showDailyRSS(); exit; }
2385 if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'do=daily')) { showDaily(); exit; }
2386 if (isset($_SERVER["QUERY_STRING"]) && startswith($_SERVER["QUERY_STRING"],'ws=')) { processWS(); exit; } // Webservices (for jQuery/jQueryUI)
2387 if (!isset($_SESSION['LINKS_PER_PAGE'])) $_SESSION['LINKS_PER_PAGE']=$GLOBALS['config']['LINKS_PER_PAGE'];
2388 renderPage();
2389 ?>