lib/util.php

   1 <?php
   2 /*
   3  * Laconica - a distributed open-source microblogging tool
   4  * Copyright (C) 2008, Controlez-Vous, Inc.
   5  *
   6  * This program is free software: you can redistribute it and/or modify
   7  * it under the terms of the GNU Affero General Public License as published by
   8  * the Free Software Foundation, either version 3 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU Affero General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Affero General Public License
  17  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 /* XXX: break up into separate modules (HTTP, HTML, user, files) */
  21
  22 # Show a server error
  23
  24 function common_server_error($msg, $code=500) {
  25         static $status = array(500 => 'Internal Server Error',
  26                                                    501 => 'Not Implemented',
  27                                                    502 => 'Bad Gateway',
  28                                                    503 => 'Service Unavailable',
  29                                                    504 => 'Gateway Timeout',
  30                                                    505 => 'HTTP Version Not Supported');
  31
  32         if (!array_key_exists($code, $status)) {
  33                 $code = 500;
  34         }
  35
  36         $status_string = $status[$code];
  37
  38         header('HTTP/1.1 '.$code.' '.$status_string);
  39         header('Content-type: text/plain');
  40
  41         print $msg;
  42         print "\n";
  43         exit();
  44 }
  45
  46 # Show a user error
  47 function common_user_error($msg, $code=400) {
  48         static $status = array(400 => 'Bad Request',
  49                                                    401 => 'Unauthorized',
  50                                                    402 => 'Payment Required',
  51                                                    403 => 'Forbidden',
  52                                                    404 => 'Not Found',
  53                                                    405 => 'Method Not Allowed',
  54                                                    406 => 'Not Acceptable',
  55                                                    407 => 'Proxy Authentication Required',
  56                                                    408 => 'Request Timeout',
  57                                                    409 => 'Conflict',
  58                                                    410 => 'Gone',
  59                                                    411 => 'Length Required',
  60                                                    412 => 'Precondition Failed',
  61                                                    413 => 'Request Entity Too Large',
  62                                                    414 => 'Request-URI Too Long',
  63                                                    415 => 'Unsupported Media Type',
  64                                                    416 => 'Requested Range Not Satisfiable',
  65                                                    417 => 'Expectation Failed');
  66
  67         if (!array_key_exists($code, $status)) {
  68                 $code = 400;
  69         }
  70
  71         $status_string = $status[$code];
  72
  73         header('HTTP/1.1 '.$code.' '.$status_string);
  74
  75         common_show_header('Error');
  76         common_element('div', array('class' => 'error'), $msg);
  77         common_show_footer();
  78 }
  79
  80 $xw = null;
  81
  82 # Start an HTML element
  83 function common_element_start($tag, $attrs=NULL) {
  84         global $xw;
  85         $xw->startElement($tag);
  86         if (is_array($attrs)) {
  87                 foreach ($attrs as $name => $value) {
  88                         $xw->writeAttribute($name, $value);
  89                 }
  90         } else if (is_string($attrs)) {
  91                 $xw->writeAttribute('class', $attrs);
  92         }
  93 }
  94
  95 function common_element_end($tag) {
  96         global $xw;
  97         $xw->endElement();
  98 }
  99
 100 function common_element($tag, $attrs=NULL, $content=NULL) {
 101     common_element_start($tag, $attrs);
 102         if ($content) {
 103                 global $xw;
 104                 $xw->text($content);
 105         }
 106         common_element_end($tag);
 107 }
 108
 109 function common_start_xml($doc=NULL, $public=NULL, $system=NULL) {
 110         global $xw;
 111         $xw = new XMLWriter();
 112         $xw->openURI('php://output');
 113         $xw->setIndent(true);
 114         $xw->startDocument('1.0', 'UTF-8');
 115         if ($doc) {
 116                 $xw->writeDTD($doc, $public, $system);
 117         }
 118 }
 119
 120 function common_end_xml() {
 121         global $xw;
 122         $xw->endDocument();
 123         $xw->flush();
 124 }
 125
 126 function common_show_header($pagetitle, $callable=NULL, $data=NULL, $notice=NULL) {
 127         global $config, $xw;
 128
 129         header('Content-Type: application/xhtml+xml');
 130
 131         common_start_xml('html',
 132                                          '-//W3C//DTD XHTML 1.0 Strict//EN',
 133                                          'http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd');
 134
 135         # FIXME: correct language for interface
 136
 137         common_element_start('html', array('xmlns' => 'http://www.w3.org/1999/xhtml',
 138                                                                            'xml:lang' => 'en',
 139                                                                            'lang' => 'en'));
 140
 141         common_element_start('head');
 142         common_element('title', NULL,
 143                                    $pagetitle . " - " . $config['site']['name']);
 144         common_element('link', array('rel' => 'stylesheet',
 145                                                                  'type' => 'text/css',
 146                                                                  'href' => theme_path('display.css'),
 147                                                                  'media' => 'screen, projection, tv'));
 148         foreach (array(6,7) as $ver) {
 149                 if (file_exists(theme_file('ie'.$ver.'.css'))) {
 150                         # Yes, IE people should be put in jail.
 151                         $xw->writeComment('[if lte IE '.$ver.']><link rel="stylesheet" type="text/css" '.
 152                                                           'href="'.theme_path('ie'.$ver.'.css').' /><![endif]');
 153                 }
 154         }
 155         if ($callable) {
 156                 if ($data) {
 157                         call_user_func($callable, $data);
 158                 } else {
 159                         call_user_func($callable);
 160                 }
 161         }
 162         common_element_end('head');
 163         common_element_start('body');
 164         common_element_start('div', array('id' => 'wrap'));
 165         common_element_start('div', array('id' => 'header'));
 166         common_nav_menu();
 167         common_element_start('a', array('href' => common_local_url('public')));
 168         common_element('img', array('src' => ($config['site']['logo']) ?
 169                                                                 ($config['site']['logo']) : theme_path('logo.png'),
 170                                                                 'alt' => $config['site']['name'],
 171                                                                 'id' => 'logo'));
 172         common_element_end('a');
 173         if (common_logged_in()) {
 174                 common_notice_form();
 175         }
 176         common_element_end('div');
 177         common_element_start('div', array('id' => 'content'));
 178         if (common_logged_in()) {
 179                 common_views_menu();
 180         }
 181 }
 182
 183 function common_show_footer() {
 184         global $xw, $config;
 185         common_element_end('div'); # content div
 186         common_foot_menu();
 187         common_element_start('div', 'footer');
 188         global $config, $xw;
 189         common_element('img', array('class' => 'license',
 190                                                                 'id' => 'cc',
 191                                                                 'src' => $config['license']['image'],
 192                                                                 'alt' => $config['license']['title']));
 193         common_element_start('p');
 194         common_text(_t('Unless otherwise specified, contents of this site are copyright by the contributors and available under the '));
 195         common_element('a', array('class' => 'license',
 196                                                           'rel' => 'license',
 197                                                           href => $config['license']['url']),
 198                                    $config['license']['title']);
 199         common_text(_t('. Contributors should be attributed by full name or nickname.'));
 200         common_element_end('p');
 201         common_element_end('div');
 202         common_element_end('div');
 203         common_element_end('body');
 204         common_element_end('html');
 205         common_end_xml();
 206 }
 207
 208 function common_text($txt) {
 209         global $xw;
 210         $xw->text($txt);
 211 }
 212
 213 function common_raw($xml) {
 214         global $xw;
 215         $xw->writeRaw($xml);
 216 }
 217
 218 function common_nav_menu() {
 219         $user = common_current_user();
 220         common_element_start('ul', array('id' => 'nav'));
 221         common_menu_item(common_local_url('public'), _t('Public'));
 222         common_menu_item(common_local_url('doc', array('title' => 'help')),
 223                                          _t('Help'));
 224         if ($user) {
 225                 common_menu_item(common_local_url('profilesettings'),
 226                                                  _t('Settings'));
 227                 common_menu_item(common_local_url('logout'),
 228                                                  _t('Logout'));
 229         } else {
 230                 common_menu_item(common_local_url('login'), _t('Login'));
 231                 common_menu_item(common_local_url('register'), _t('Register'));
 232         }
 233         common_element_end('ul');
 234 }
 235
 236 function common_views_menu() {
 237         common_element_start('ul', array('id' => 'nav_views'));
 238         common_menu_item(common_local_url('all', array('nickname' =>
 239                                                                                                    $user->nickname)),
 240                                          _t('Home'));
 241         common_menu_item(common_local_url('showstream', array('nickname' =>
 242                                                                                                                   $user->nickname)),
 243                                          _t('Profile'),  $user->fullname || $user->nickname);
 244         common_element_end('ul');
 245 }
 246
 247 function common_foot_menu() {
 248         common_element_start('ul', array('id' => 'nav_sub'));
 249         common_menu_item(common_local_url('doc', array('title' => 'about')),
 250                                          _t('About'));
 251         common_menu_item(common_local_url('doc', array('title' => 'privacy')),
 252                                          _t('Privacy'));
 253         common_menu_item(common_local_url('doc', array('title' => 'source')),
 254                                          _t('Source'));
 255         common_element_end('ul');
 256 }
 257
 258 function common_menu_item($url, $text, $title=NULL) {
 259         $attrs['href'] = $url;
 260         if ($title) {
 261                 $attrs['title'] = $title;
 262         }
 263         common_element_start('li');
 264         common_element('a', $attrs, $text);
 265         common_element_end('li');
 266 }
 267
 268 function common_input($id, $label, $value=NULL) {
 269         common_element_start('p');
 270         common_element('label', array('for' => $id), $label);
 271         $attrs = array('name' => $id,
 272                                    'type' => 'text',
 273                                    'id' => $id);
 274         if ($value) {
 275                 $attrs['value'] = htmlspecialchars($value);
 276         }
 277         common_element('input', $attrs);
 278         common_element_end('p');
 279 }
 280
 281 function common_hidden($id, $value) {
 282         common_element('input', array('name' => $id,
 283                                                                   'type' => 'hidden',
 284                                                                   'id' => $id,
 285                                                                   'value' => $value));
 286 }
 287
 288 function common_password($id, $label) {
 289         common_element_start('p');
 290         common_element('label', array('for' => $id), $label);
 291         $attrs = array('name' => $id,
 292                                    'type' => 'password',
 293                                    'id' => $id);
 294         common_element('input', $attrs);
 295         common_element_end('p');
 296 }
 297
 298 function common_submit($id, $label) {
 299         global $xw;
 300         common_element_start('p');
 301         common_element_start('label', array('for' => $id));
 302         $xw->writeRaw('&nbsp;');
 303         common_element_end('label');
 304         common_element('input', array('type' => 'submit',
 305                                                                   'id' => $id,
 306                                                                   'name' => $id,
 307                                                                   'value' => $label,
 308                                                                   'class' => 'button'));
 309         common_element_end('p');
 310 }
 311
 312 function common_textarea($id, $label, $content=NULL) {
 313         common_element_start('p');
 314         common_element('label', array('for' => $id), $label);
 315         common_element('textarea', array('rows' => 3,
 316                                                                          'cols' => 40,
 317                                                                          'name' => $id,
 318                                                                          'id' => $id,
 319                                                                          'class' => 'width50'),
 320                                    ($content) ? $content : ' ');
 321         common_element_end('p');
 322 }
 323
 324 # salted, hashed passwords are stored in the DB
 325
 326 function common_munge_password($id, $password) {
 327         return md5($id . $password);
 328 }
 329
 330 # check if a username exists and has matching password
 331 function common_check_user($nickname, $password) {
 332         $user = User::staticGet('nickname', $nickname);
 333         if (is_null($user)) {
 334                 return false;
 335         } else {
 336                 return (0 == strcmp(common_munge_password($password, $user->id),
 337                                                         $user->password));
 338         }
 339 }
 340
 341 # is the current user logged in?
 342 function common_logged_in() {
 343         return (!is_null(common_current_user()));
 344 }
 345
 346 function common_have_session() {
 347         return (0 != strcmp(session_id(), ''));
 348 }
 349
 350 function common_ensure_session() {
 351         if (!common_have_session()) {
 352                 @session_start();
 353         }
 354 }
 355
 356 function common_set_user($nickname) {
 357         if (is_null($nickname) && common_have_session()) {
 358                 unset($_SESSION['userid']);
 359                 return true;
 360         } else {
 361                 $user = User::staticGet('nickname', $nickname);
 362                 if ($user) {
 363                         common_ensure_session();
 364                         $_SESSION['userid'] = $user->id;
 365                         return true;
 366                 } else {
 367                         return false;
 368                 }
 369         }
 370         return false;
 371 }
 372
 373 # who is the current user?
 374 function common_current_user() {
 375         static $user = NULL; # FIXME: global memcached
 376         if (is_null($user)) {
 377                 common_ensure_session();
 378                 $id = $_SESSION['userid'];
 379                 if ($id) {
 380                         $user = User::staticGet($id);
 381                 }
 382         }
 383         return $user;
 384 }
 385
 386 # get canonical version of nickname for comparison
 387 function common_canonical_nickname($nickname) {
 388         # XXX: UTF-8 canonicalization (like combining chars)
 389         return $nickname;
 390 }
 391
 392 # get canonical version of email for comparison
 393 function common_canonical_email($email) {
 394         # XXX: canonicalize UTF-8
 395         # XXX: lcase the domain part
 396         return $email;
 397 }
 398
 399 define('URL_REGEX', '^|[ \t\r\n])((ftp|http|https|gopher|mailto|news|nntp|telnet|wais|file|prospero|aim|webcal):(([A-Za-z0-9$_.+!*(),;/?:@&~=-])|%[A-Fa-f0-9]{2}){2,}(#([a-zA-Z0-9][a-zA-Z0-9$_.+!*(),;/?:@&~=%-]*))?([A-Za-z0-9$_+!*();/?:~-]))');
 400
 401 function common_render_content($text, $notice) {
 402         $r = htmlspecialchars($text);
 403         $id = $notice->profile_id;
 404         $r = preg_replace('@https?://\S+@', '<a href="\0" class="extlink">\0</a>', $r);
 405         $r = preg_replace('/(^|\b)@([\w-]+)($|\b)/e', "'\\1@'.common_at_link($id, '\\2').'\\3'", $r);
 406         # XXX: # tags
 407         # XXX: machine tags
 408         return $r;
 409 }
 410
 411 function common_at_link($sender_id, $nickname) {
 412         # Try to find profiles this profile is subscribed to that have this nickname
 413         $recipient = new Profile();
 414         # XXX: chokety and bad
 415         $recipient->whereAdd('EXISTS (SELECT subscribed from subscription where subscriber = '.$sender_id.' and subscribed = id)', 'AND');
 416         $recipient->whereAdd('nickname = "' . trim($nickname) . '"', 'AND');
 417         if ($recipient->find(TRUE)) {
 418                 return '<a href="'.htmlspecialchars($recipient->profileurl).'" class="atlink tolistenee">'.$nickname.'</a>';
 419         }
 420         # Try to find profiles that listen to this profile and that have this nickname
 421         $recipient = new Profile();
 422         # XXX: chokety and bad
 423         $recipient->whereAdd('EXISTS (SELECT subscriber from subscription where subscribed = '.$sender_id.' and subscriber = id)', 'AND');
 424         $recipient->whereAdd('nickname = "' . trim($nickname) . '"', 'AND');
 425         if ($recipient->find(TRUE)) {
 426                 return '<a href="'.htmlspecialchars($recipient->profileurl).'" class="atlink tolistener">'.$nickname.'</a>';
 427         }
 428         # If this is a local user, try to find a local user with that nickname.
 429         $sender = User::staticGet($sender_id);
 430         if ($sender) {
 431                 $recipient_user = User::staticGet('nickname', $nickname);
 432                 if ($recipient_user) {
 433                         $recipient = $recipient->getProfile();
 434                         return '<a href="'.htmlspecialchars($recipient->profileurl).'" class="atlink usertouser">'.$nickname.'</a>';
 435                 }
 436         }
 437         # Otherwise, no links. @messages from local users to remote users,
 438         # or from remote users to other remote users, are just
 439         # outside our ability to make intelligent guesses about
 440         return $nickname;
 441 }
 442
 443 // where should the avatar go for this user?
 444
 445 function common_avatar_filename($id, $extension, $size=NULL, $extra=NULL) {
 446         global $config;
 447
 448         if ($size) {
 449                 return $id . '-' . $size . (($extra) ? ('-' . $extra) : '') . $extension;
 450         } else {
 451                 return $id . '-original' . (($extra) ? ('-' . $extra) : '') . $extension;
 452         }
 453 }
 454
 455 function common_avatar_path($filename) {
 456         global $config;
 457         return INSTALLDIR . '/avatar/' . $filename;
 458 }
 459
 460 function common_avatar_url($filename) {
 461         return common_path('avatar/'.$filename);
 462 }
 463
 464 function common_default_avatar($size) {
 465         static $sizenames = array(AVATAR_PROFILE_SIZE => 'profile',
 466                                                           AVATAR_STREAM_SIZE => 'stream',
 467                                                           AVATAR_MINI_SIZE => 'mini');
 468         global $config;
 469
 470         return common_path($config['avatar']['default'][$sizenames[$size]]);
 471 }
 472
 473 function common_local_url($action, $args=NULL) {
 474         global $config;
 475         if ($config['site']['fancy']) {
 476                 return common_fancy_url($action, $args);
 477         } else {
 478                 return common_simple_url($action, $args);
 479         }
 480 }
 481
 482 function common_fancy_url($action, $args=NULL) {
 483         switch (strtolower($action)) {
 484          case 'public':
 485                 return common_path('');
 486          case 'publicrss':
 487                 return common_path('rss');
 488          case 'doc':
 489                 return common_path('doc/'.$args['title']);
 490          case 'login':
 491          case 'logout':
 492          case 'register':
 493          case 'subscribe':
 494          case 'unsubscribe':
 495                 return common_path('main/'.$action);
 496          case 'avatar':
 497          case 'password':
 498                 return common_path('settings/'.$action);
 499          case 'profilesettings':
 500                 return common_path('settings/profile');
 501          case 'newnotice':
 502                 return common_path('notice/new');
 503          case 'shownotice':
 504                 return common_path('notice/'.$args['notice']);
 505          case 'subscriptions':
 506          case 'subscribed':
 507          case 'xrds':
 508          case 'all':
 509          case 'foaf':
 510                 return common_path($args['nickname'].'/'.$action);
 511          case 'allrss':
 512                 return common_path($args['nickname'].'/all/rss');
 513          case 'userrss':
 514                 return common_path($args['nickname'].'/rss');
 515          case 'showstream':
 516                 return common_path($args['nickname']);
 517          default:
 518                 return common_simple_url($action, $args);
 519         }
 520 }
 521
 522 function common_simple_url($action, $args=NULL) {
 523         global $config;
 524         /* XXX: pretty URLs */
 525         $extra = '';
 526         if ($args) {
 527                 foreach ($args as $key => $value) {
 528                         $extra .= "&${key}=${value}";
 529                 }
 530         }
 531         return common_path("index.php?action=${action}${extra}");
 532 }
 533
 534 function common_path($relative) {
 535         global $config;
 536         $pathpart = ($config['site']['path']) ? $config['site']['path']."/" : '';
 537         return "http://".$config['site']['server'].'/'.$pathpart.$relative;
 538 }
 539
 540 function common_date_string($dt) {
 541         // XXX: do some sexy date formatting
 542         // return date(DATE_RFC822, $dt);
 543         return $dt;
 544 }
 545
 546 function common_date_w3dtf($dt) {
 547         $t = strtotime($dt);
 548         return date(DATE_W3C, $t);
 549 }
 550
 551 function common_redirect($url, $code=307) {
 552         static $status = array(301 => "Moved Permanently",
 553                                                    302 => "Found",
 554                                                    303 => "See Other",
 555                                                    307 => "Temporary Redirect");
 556         header("Status: ${code} $status[$code]");
 557         header("Location: $url");
 558         common_element('a', array('href' => $url), $url);
 559 }
 560
 561 function common_broadcast_notice($notice, $remote=false) {
 562         // XXX: optionally use a queue system like http://code.google.com/p/microapps/wiki/NQDQ
 563         if (!$remote) {
 564                 # Make sure we have the OMB stuff
 565                 require_once(INSTALLDIR.'/lib/omb.php');
 566                 omb_broadcast_remote_subscribers($notice);
 567         }
 568         // XXX: broadcast notices to Jabber
 569         // XXX: broadcast notices to SMS
 570         // XXX: broadcast notices to other IM
 571         return true;
 572 }
 573
 574
 575 function common_profile_url($nickname) {
 576         return common_local_url('showstream', array('nickname' => $nickname));
 577 }
 578
 579 # Don't call if nobody's logged in
 580
 581 function common_notice_form() {
 582         $user = common_current_user();
 583         assert(!is_null($user));
 584         common_element_start('form', array('id' => 'status_form',
 585                                                                            'method' => 'POST',
 586                                                                            'action' => common_local_url('newnotice')));
 587         common_element_start('p');
 588         common_element('label', array('for' => 'status_update',
 589                                                                   'id' => 'status_label'),
 590                                    _t('What\'s up, ').$user->nickname.'?');
 591         common_element('textarea', array('id' => 'status_textarea'));
 592         common_element('input', array('id' => 'status_submit',
 593                                                                   'type' => 'submit',
 594                                                                   'value' => _t('Send')));
 595         common_element_end('p');
 596         common_element_end('form');
 597 }
 598
 599 function common_mint_tag($extra) {
 600         global $config;
 601         return
 602           'tag:'.$config['tag']['authority'].','.
 603           $config['tag']['date'].':'.$config['tag']['prefix'].$extra;
 604 }
 605
 606 # Should make up a reasonable root URL
 607
 608 function common_root_url() {
 609         return common_path('');
 610 }
 611
 612 # returns $bytes bytes of random data as a hexadecimal string
 613 # "good" here is a goal and not a guarantee
 614
 615 function common_good_rand($bytes) {
 616         # XXX: use random.org...?
 617         if (file_exists('/dev/urandom')) {
 618                 return common_urandom($bytes);
 619         } else { # FIXME: this is probably not good enough
 620                 return common_mtrand($bytes);
 621         }
 622 }
 623
 624 function common_urandom($bytes) {
 625         $h = fopen('/dev/urandom', 'rb');
 626         # should not block
 627         $src = fread($h, $bytes);
 628         fclose($h);
 629         $enc = '';
 630         for ($i = 0; $i < $bytes; $i++) {
 631                 $enc .= sprintf("%02x", (ord($src[$i])));
 632         }
 633         return $enc;
 634 }
 635
 636 function common_mtrand($bytes) {
 637         $enc = '';
 638         for ($i = 0; $i < $bytes; $i++) {
 639                 $enc .= sprintf("%02x", mt_rand(0, 255));
 640         }
 641         return $enc;
 642 }
 643
 644 function common_set_returnto($url) {
 645         common_ensure_session();
 646         $_SESSION['returnto'] = $url;
 647 }
 648
 649 function common_get_returnto() {
 650         common_ensure_session();
 651         return $_SESSION['returnto'];
 652 }
 653
 654 function common_timestamp() {
 655         return date('YmdHis');
 656 }
 657
 658 // XXX: set up gettext
 659
 660 function _t($str) {
 661         return $str;
 662 }
 663
 664 function common_ensure_syslog() {
 665         static $initialized = false;
 666         if (!$initialized) {
 667                 global $config;
 668                 define_syslog_variables();
 669                 openlog($config['syslog']['appname'], 0, LOG_USER);
 670                 $initialized = true;
 671         }
 672 }
 673
 674 function common_log($priority, $msg, $filename=NULL) {
 675         common_ensure_syslog();
 676         syslog($priority, $msg);
 677 }
 678
 679 function common_debug($msg, $filename=NULL) {
 680         if ($filename) {
 681                 common_log(LOG_DEBUG, basename($filename).' - '.$msg);
 682         } else {
 683                 common_log(LOG_DEBUG, $msg);
 684         }
 685 }
 686
 687 function common_valid_http_url($url) {
 688         return Validate::uri($url, array('allowed_schemes' => array('http', 'https')));
 689 }
 690
 691 function common_valid_tag($tag) {
 692         if (preg_match('/^tag:(.*?),(\d{4}(-\d{2}(-\d{2})?)?):(.*)$/', $tag, $matches)) {
 693                 return (Validate::email($matches[1]) ||
 694                                 preg_match('/^([\w-\.]+)$/', $matches[1]));
 695         }
 696         return false;
 697 }
 698
 699 # Does a little before-after block for next/prev page
 700
 701 function common_pagination($have_before, $have_after, $page, $action, $args=NULL) {
 702
 703         if ($have_before || $have_after) {
 704                 common_element_start('div', array('id' => 'pagination'));
 705                 common_element_start('ul', array('id' => 'nav_pagination'));
 706         }
 707
 708         if ($have_before) {
 709                 $pargs = array('page' => $page-1);
 710                 $newargs = ($args) ? array_merge($args,$pargs) : $pargs;
 711
 712                 common_element_start('li', 'before');
 713                 common_element('a', array('href' => common_local_url($action, $newargs)),
 714                                            _t('« Before'));
 715                 common_element_end('li');
 716         }
 717
 718         if ($have_after) {
 719                 $pargs = array('page' => $page+1);
 720                 $newargs = ($args) ? array_merge($args,$pargs) : $pargs;
 721                 common_element_start('li', 'after');
 722                 common_element('a', array('href' => common_local_url($action, $newargs)),
 723                                                    _t('After »'));
 724                 common_element_end('li');
 725         }
 726
 727         if ($have_before || $have_after) {
 728                 common_element_end('ul');
 729                 common_element_end('div');
 730         }
 731 }