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         $xw->flush();
 124 }
 125
 126 define('PAGE_TYPE_PREFS', 'application/xhtml+xml,text/html;q=0.7,application/xml;q=0.3,text/xml;q=0.2');
 127
 128 function common_show_header($pagetitle, $callable=NULL, $data=NULL, $headercall=NULL) {
 129         global $config, $xw;
 130
 131         $httpaccept = isset($_SERVER['HTTP_ACCEPT']) ? $_SERVER['HTTP_ACCEPT'] : NULL;
 132
 133         # XXX: allow content negotiation for RDF, RSS, or XRDS
 134
 135         $type = common_negotiate_type(common_accept_to_prefs($httpaccept),
 136                                                                   common_accept_to_prefs(PAGE_TYPE_PREFS));
 137
 138         if (!$type) {
 139                 common_client_error(_t('This page is not available in a media type you accept'), 406);
 140                 exit(0);
 141         }
 142
 143         header('Content-Type: '.$type);
 144
 145         common_start_xml('html',
 146                                          '-//W3C//DTD XHTML 1.0 Strict//EN',
 147                                          'http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd');
 148
 149         # FIXME: correct language for interface
 150
 151         common_element_start('html', array('xmlns' => 'http://www.w3.org/1999/xhtml',
 152                                                                            'xml:lang' => 'en',
 153                                                                            'lang' => 'en'));
 154
 155         common_element_start('head');
 156         common_element('title', NULL,
 157                                    $pagetitle . " - " . $config['site']['name']);
 158         common_element('link', array('rel' => 'stylesheet',
 159                                                                  'type' => 'text/css',
 160                                                                  'href' => theme_path('display.css'),
 161                                                                  'media' => 'screen, projection, tv'));
 162         foreach (array(6,7) as $ver) {
 163                 if (file_exists(theme_file('ie'.$ver.'.css'))) {
 164                         # Yes, IE people should be put in jail.
 165                         $xw->writeComment('[if lte IE '.$ver.']><link rel="stylesheet" type="text/css" '.
 166                                                           'href="'.theme_path('ie'.$ver.'.css').' /><![endif]');
 167                 }
 168         }
 169         if ($callable) {
 170                 if ($data) {
 171                         call_user_func($callable, $data);
 172                 } else {
 173                         call_user_func($callable);
 174                 }
 175         }
 176         common_element_end('head');
 177         common_element_start('body');
 178         common_element_start('div', array('id' => 'wrap'));
 179         common_element_start('div', array('id' => 'header'));
 180         common_nav_menu();
 181         if ($config['site']['logo'] || file_exists(theme_file('logo.png'))) {
 182                 common_element_start('a', array('href' => common_local_url('public')));
 183                 common_element('img', array('src' => ($config['site']['logo']) ?
 184                                                                         ($config['site']['logo']) : theme_path('logo.png'),
 185                                                                         'alt' => $config['site']['name'],
 186                                                                         'id' => 'logo'));
 187                 common_element_end('a');
 188         }
 189         common_element('h1', 'pagetitle', $pagetitle);
 190         common_element('h2', 'sitename', $config['site']['name']);
 191
 192         if ($headercall) {
 193                 if ($data) {
 194                         call_user_func($headercall, $data);
 195                 } else {
 196                         call_user_func($headercall);
 197                 }
 198         }
 199         common_element_end('div');
 200         common_element_start('div', array('id' => 'content'));
 201 }
 202
 203 function common_show_footer() {
 204         global $xw, $config;
 205         common_element_end('div'); # content div
 206         common_foot_menu();
 207         common_element_start('div', array('id' => 'footer'));
 208         common_element('img', array('id' => 'cc',
 209                                                                 'src' => $config['license']['image'],
 210                                                                 'alt' => $config['license']['title']));
 211         common_element_start('p');
 212         common_text(_t('Unless otherwise specified, contents of this site are copyright by the contributors and available under the '));
 213         common_element('a', array('class' => 'license',
 214                                                           'rel' => 'license',
 215                                                           href => $config['license']['url']),
 216                                    $config['license']['title']);
 217         common_text(_t('. Contributors should be attributed by full name or nickname.'));
 218         common_element_end('p');
 219         common_element_end('div');
 220         common_element_end('div');
 221         common_element_end('body');
 222         common_element_end('html');
 223         common_end_xml();
 224 }
 225
 226 function common_text($txt) {
 227         global $xw;
 228         $xw->text($txt);
 229 }
 230
 231 function common_raw($xml) {
 232         global $xw;
 233         $xw->writeRaw($xml);
 234 }
 235
 236 function common_nav_menu() {
 237         $user = common_current_user();
 238         common_element_start('ul', array('id' => 'nav'));
 239         if ($user) {
 240                 common_menu_item(common_local_url('all', array('nickname' => $user->nickname)),
 241                                                  _t('Home'));
 242         }
 243         common_menu_item(common_local_url('public'), _t('Public'));
 244         common_menu_item(common_local_url('doc', array('title' => 'help')),
 245                                          _t('Help'));
 246         if ($user) {
 247                 common_menu_item(common_local_url('profilesettings'),
 248                                                  _t('Settings'));
 249                 common_menu_item(common_local_url('logout'),
 250                                                  _t('Logout'));
 251         } else {
 252                 common_menu_item(common_local_url('login'), _t('Login'));
 253                 common_menu_item(common_local_url('register'), _t('Register'));
 254         }
 255         common_element_end('ul');
 256 }
 257
 258 function common_foot_menu() {
 259         common_element_start('ul', array('id' => 'nav_sub'));
 260         common_menu_item(common_local_url('doc', array('title' => 'about')),
 261                                          _t('About'));
 262         common_menu_item(common_local_url('doc', array('title' => 'privacy')),
 263                                          _t('Privacy'));
 264         common_menu_item(common_local_url('doc', array('title' => 'source')),
 265                                          _t('Source'));
 266         common_element_end('ul');
 267 }
 268
 269 function common_menu_item($url, $text, $title=NULL, $is_selected=false) {
 270         $lattrs = array();
 271         if ($is_selected) {
 272                 $lattrs['class'] = 'current';
 273         }
 274         common_element_start('li', $lattrs);
 275         $attrs['href'] = $url;
 276         if ($title) {
 277                 $attrs['title'] = $title;
 278         }
 279         common_element('a', $attrs, $text);
 280         common_element_end('li');
 281 }
 282
 283 function common_input($id, $label, $value=NULL,$instructions=NULL) {
 284         common_element_start('p');
 285         common_element('label', array('for' => $id), $label);
 286         $attrs = array('name' => $id,
 287                                    'type' => 'text',
 288                                    'id' => $id);
 289         if ($value) {
 290                 $attrs['value'] = htmlspecialchars($value);
 291         }
 292         common_element('input', $attrs);
 293         if ($instructions) {
 294                 common_element('span', 'input_instructions', $instructions);
 295         }
 296         common_element_end('p');
 297 }
 298
 299 function common_hidden($id, $value) {
 300         common_element('input', array('name' => $id,
 301                                                                   'type' => 'hidden',
 302                                                                   'id' => $id,
 303                                                                   'value' => $value));
 304 }
 305
 306 function common_password($id, $label, $instructions=NULL) {
 307         common_element_start('p');
 308         common_element('label', array('for' => $id), $label);
 309         $attrs = array('name' => $id,
 310                                    'type' => 'password',
 311                                    'id' => $id);
 312         common_element('input', $attrs);
 313         if ($instructions) {
 314                 common_element('span', 'input_instructions', $instructions);
 315         }
 316         common_element_end('p');
 317 }
 318
 319 function common_submit($id, $label) {
 320         global $xw;
 321         common_element_start('p');
 322         common_element('input', array('type' => 'submit',
 323                                                                   'id' => $id,
 324                                                                   'name' => $id,
 325                                                                   'value' => $label));
 326         common_element_end('p');
 327 }
 328
 329 function common_textarea($id, $label, $content=NULL, $instructions=NULL) {
 330         common_element_start('p');
 331         common_element('label', array('for' => $id), $label);
 332         common_element('textarea', array('rows' => 3,
 333                                                                          'cols' => 40,
 334                                                                          'name' => $id,
 335                                                                          'id' => $id),
 336                                    ($content) ? $content : ' ');
 337         if ($instructions) {
 338                 common_element('span', 'input_instructions', $instructions);
 339         }
 340         common_element_end('p');
 341 }
 342
 343 # salted, hashed passwords are stored in the DB
 344
 345 function common_munge_password($id, $password) {
 346         return md5($id . $password);
 347 }
 348
 349 # check if a username exists and has matching password
 350 function common_check_user($nickname, $password) {
 351         $user = User::staticGet('nickname', $nickname);
 352         if (is_null($user)) {
 353                 return false;
 354         } else {
 355                 return (0 == strcmp(common_munge_password($password, $user->id),
 356                                                         $user->password));
 357         }
 358 }
 359
 360 # is the current user logged in?
 361 function common_logged_in() {
 362         return (!is_null(common_current_user()));
 363 }
 364
 365 function common_have_session() {
 366         return (0 != strcmp(session_id(), ''));
 367 }
 368
 369 function common_ensure_session() {
 370         if (!common_have_session()) {
 371                 @session_start();
 372         }
 373 }
 374
 375 function common_set_user($nickname) {
 376         if (is_null($nickname) && common_have_session()) {
 377                 unset($_SESSION['userid']);
 378                 return true;
 379         } else {
 380                 $user = User::staticGet('nickname', $nickname);
 381                 if ($user) {
 382                         common_ensure_session();
 383                         $_SESSION['userid'] = $user->id;
 384                         return true;
 385                 } else {
 386                         return false;
 387                 }
 388         }
 389         return false;
 390 }
 391
 392 # who is the current user?
 393 function common_current_user() {
 394         static $user = NULL; # FIXME: global memcached
 395         if (is_null($user)) {
 396                 common_ensure_session();
 397                 $id = $_SESSION['userid'];
 398                 if ($id) {
 399                         $user = User::staticGet($id);
 400                 }
 401         }
 402         return $user;
 403 }
 404
 405 # get canonical version of nickname for comparison
 406 function common_canonical_nickname($nickname) {
 407         # XXX: UTF-8 canonicalization (like combining chars)
 408         return strtolower($nickname);
 409 }
 410
 411 # get canonical version of email for comparison
 412 function common_canonical_email($email) {
 413         # XXX: canonicalize UTF-8
 414         # XXX: lcase the domain part
 415         return $email;
 416 }
 417
 418 define('URL_REGEX', '^|[ \t\r\n])((ftp|http|https|gopher|mailto|news|nntp|telnet|wais|file|prospero|aim|webcal):(([A-Za-z0-9$_.+!*(),;/?:@&~=-])|%[A-Fa-f0-9]{2}){2,}(#([a-zA-Z0-9][a-zA-Z0-9$_.+!*(),;/?:@&~=%-]*))?([A-Za-z0-9$_+!*();/?:~-]))');
 419
 420 function common_render_content($text, $notice) {
 421         $r = htmlspecialchars($text);
 422         $id = $notice->profile_id;
 423         $r = preg_replace('@https?://\S+@', '<a href="\0" class="extlink">\0</a>', $r);
 424         $r = preg_replace('/(^|\b)@([\w-]+)($|\b)/e', "'\\1@'.common_at_link($id, '\\2').'\\3'", $r);
 425         # XXX: # tags
 426         # XXX: machine tags
 427         return $r;
 428 }
 429
 430 function common_at_link($sender_id, $nickname) {
 431         # Try to find profiles this profile is subscribed to that have this nickname
 432         $recipient = new Profile();
 433         # XXX: chokety and bad
 434         $recipient->whereAdd('EXISTS (SELECT subscribed from subscription where subscriber = '.$sender_id.' and subscribed = id)', 'AND');
 435         $recipient->whereAdd('nickname = "' . trim($nickname) . '"', 'AND');
 436         if ($recipient->find(TRUE)) {
 437                 return '<a href="'.htmlspecialchars($recipient->profileurl).'" class="atlink tolistenee">'.$nickname.'</a>';
 438         }
 439         # Try to find profiles that listen to this profile and that have this nickname
 440         $recipient = new Profile();
 441         # XXX: chokety and bad
 442         $recipient->whereAdd('EXISTS (SELECT subscriber from subscription where subscribed = '.$sender_id.' and subscriber = id)', 'AND');
 443         $recipient->whereAdd('nickname = "' . trim($nickname) . '"', 'AND');
 444         if ($recipient->find(TRUE)) {
 445                 return '<a href="'.htmlspecialchars($recipient->profileurl).'" class="atlink tolistener">'.$nickname.'</a>';
 446         }
 447         # If this is a local user, try to find a local user with that nickname.
 448         $sender = User::staticGet($sender_id);
 449         if ($sender) {
 450                 $recipient_user = User::staticGet('nickname', $nickname);
 451                 if ($recipient_user) {
 452                         $recipient = $recipient->getProfile();
 453                         return '<a href="'.htmlspecialchars($recipient->profileurl).'" class="atlink usertouser">'.$nickname.'</a>';
 454                 }
 455         }
 456         # Otherwise, no links. @messages from local users to remote users,
 457         # or from remote users to other remote users, are just
 458         # outside our ability to make intelligent guesses about
 459         return $nickname;
 460 }
 461
 462 // where should the avatar go for this user?
 463
 464 function common_avatar_filename($id, $extension, $size=NULL, $extra=NULL) {
 465         global $config;
 466
 467         if ($size) {
 468                 return $id . '-' . $size . (($extra) ? ('-' . $extra) : '') . $extension;
 469         } else {
 470                 return $id . '-original' . (($extra) ? ('-' . $extra) : '') . $extension;
 471         }
 472 }
 473
 474 function common_avatar_path($filename) {
 475         global $config;
 476         return INSTALLDIR . '/avatar/' . $filename;
 477 }
 478
 479 function common_avatar_url($filename) {
 480         return common_path('avatar/'.$filename);
 481 }
 482
 483 function common_default_avatar($size) {
 484         static $sizenames = array(AVATAR_PROFILE_SIZE => 'profile',
 485                                                           AVATAR_STREAM_SIZE => 'stream',
 486                                                           AVATAR_MINI_SIZE => 'mini');
 487         return theme_path('default-avatar-'.$sizenames[$size].'.png');
 488 }
 489
 490 function common_local_url($action, $args=NULL) {
 491         global $config;
 492         if ($config['site']['fancy']) {
 493                 return common_fancy_url($action, $args);
 494         } else {
 495                 return common_simple_url($action, $args);
 496         }
 497 }
 498
 499 function common_fancy_url($action, $args=NULL) {
 500         switch (strtolower($action)) {
 501          case 'public':
 502                 return common_path('');
 503          case 'publicrss':
 504                 return common_path('rss');
 505          case 'doc':
 506                 return common_path('doc/'.$args['title']);
 507          case 'login':
 508          case 'logout':
 509          case 'register':
 510          case 'subscribe':
 511          case 'unsubscribe':
 512                 return common_path('main/'.$action);
 513          case 'avatar':
 514          case 'password':
 515                 return common_path('settings/'.$action);
 516          case 'profilesettings':
 517                 return common_path('settings/profile');
 518          case 'newnotice':
 519                 return common_path('notice/new');
 520          case 'shownotice':
 521                 return common_path('notice/'.$args['notice']);
 522          case 'subscriptions':
 523          case 'subscribed':
 524          case 'xrds':
 525          case 'all':
 526          case 'foaf':
 527                 return common_path($args['nickname'].'/'.$action);
 528          case 'allrss':
 529                 return common_path($args['nickname'].'/all/rss');
 530          case 'userrss':
 531                 return common_path($args['nickname'].'/rss');
 532          case 'showstream':
 533                 return common_path($args['nickname']);
 534          default:
 535                 return common_simple_url($action, $args);
 536         }
 537 }
 538
 539 function common_simple_url($action, $args=NULL) {
 540         global $config;
 541         /* XXX: pretty URLs */
 542         $extra = '';
 543         if ($args) {
 544                 foreach ($args as $key => $value) {
 545                         $extra .= "&${key}=${value}";
 546                 }
 547         }
 548         return common_path("index.php?action=${action}${extra}");
 549 }
 550
 551 function common_path($relative) {
 552         global $config;
 553         $pathpart = ($config['site']['path']) ? $config['site']['path']."/" : '';
 554         return "http://".$config['site']['server'].'/'.$pathpart.$relative;
 555 }
 556
 557 function common_date_string($dt) {
 558         // XXX: do some sexy date formatting
 559         // return date(DATE_RFC822, $dt);
 560         return $dt;
 561 }
 562
 563 function common_date_w3dtf($dt) {
 564         $t = strtotime($dt);
 565         return date(DATE_W3C, $t);
 566 }
 567
 568 function common_redirect($url, $code=307) {
 569         static $status = array(301 => "Moved Permanently",
 570                                                    302 => "Found",
 571                                                    303 => "See Other",
 572                                                    307 => "Temporary Redirect");
 573         header("Status: ${code} $status[$code]");
 574         header("Location: $url");
 575         common_element('a', array('href' => $url), $url);
 576 }
 577
 578 function common_broadcast_notice($notice, $remote=false) {
 579         // XXX: optionally use a queue system like http://code.google.com/p/microapps/wiki/NQDQ
 580         if (!$remote) {
 581                 # Make sure we have the OMB stuff
 582                 require_once(INSTALLDIR.'/lib/omb.php');
 583                 omb_broadcast_remote_subscribers($notice);
 584         }
 585         // XXX: broadcast notices to Jabber
 586         // XXX: broadcast notices to SMS
 587         // XXX: broadcast notices to other IM
 588         return true;
 589 }
 590
 591 function common_broadcast_profile($profile) {
 592         // XXX: optionally use a queue system like http://code.google.com/p/microapps/wiki/NQDQ
 593         require_once(INSTALLDIR.'/lib/omb.php');
 594         omb_broadcast_profile($profile);
 595         // XXX: Other broadcasts...?
 596         return true;
 597 }
 598
 599 function common_profile_url($nickname) {
 600         return common_local_url('showstream', array('nickname' => $nickname));
 601 }
 602
 603 # Don't call if nobody's logged in
 604
 605 function common_notice_form() {
 606         $user = common_current_user();
 607         assert(!is_null($user));
 608         common_element_start('form', array('id' => 'status_form',
 609                                                                            'method' => 'POST',
 610                                                                            'action' => common_local_url('newnotice')));
 611         common_element_start('p');
 612         common_element('label', array('for' => 'status_update',
 613                                                                   'id' => 'status_label'),
 614                                    _t('What\'s up, ').$user->nickname.'?');
 615         common_element('textarea', array('id' => 'status_textarea',
 616                                                                          'name' => 'status_textarea'));
 617         common_element('input', array('id' => 'status_submit',
 618                                                                   'name' => 'status_submit',
 619                                                                   'type' => 'submit',
 620                                                                   'value' => _t('Send')));
 621         common_element_end('p');
 622         common_element_end('form');
 623 }
 624
 625 function common_mint_tag($extra) {
 626         global $config;
 627         return
 628           'tag:'.$config['tag']['authority'].','.
 629           $config['tag']['date'].':'.$config['tag']['prefix'].$extra;
 630 }
 631
 632 # Should make up a reasonable root URL
 633
 634 function common_root_url() {
 635         return common_path('');
 636 }
 637
 638 # returns $bytes bytes of random data as a hexadecimal string
 639 # "good" here is a goal and not a guarantee
 640
 641 function common_good_rand($bytes) {
 642         # XXX: use random.org...?
 643         if (file_exists('/dev/urandom')) {
 644                 return common_urandom($bytes);
 645         } else { # FIXME: this is probably not good enough
 646                 return common_mtrand($bytes);
 647         }
 648 }
 649
 650 function common_urandom($bytes) {
 651         $h = fopen('/dev/urandom', 'rb');
 652         # should not block
 653         $src = fread($h, $bytes);
 654         fclose($h);
 655         $enc = '';
 656         for ($i = 0; $i < $bytes; $i++) {
 657                 $enc .= sprintf("%02x", (ord($src[$i])));
 658         }
 659         return $enc;
 660 }
 661
 662 function common_mtrand($bytes) {
 663         $enc = '';
 664         for ($i = 0; $i < $bytes; $i++) {
 665                 $enc .= sprintf("%02x", mt_rand(0, 255));
 666         }
 667         return $enc;
 668 }
 669
 670 function common_set_returnto($url) {
 671         common_ensure_session();
 672         $_SESSION['returnto'] = $url;
 673 }
 674
 675 function common_get_returnto() {
 676         common_ensure_session();
 677         return $_SESSION['returnto'];
 678 }
 679
 680 function common_timestamp() {
 681         return date('YmdHis');
 682 }
 683
 684 // XXX: set up gettext
 685
 686 function _t($str) {
 687         return $str;
 688 }
 689
 690 function common_ensure_syslog() {
 691         static $initialized = false;
 692         if (!$initialized) {
 693                 global $config;
 694                 define_syslog_variables();
 695                 openlog($config['syslog']['appname'], 0, LOG_USER);
 696                 $initialized = true;
 697         }
 698 }
 699
 700 function common_log($priority, $msg, $filename=NULL) {
 701         common_ensure_syslog();
 702         syslog($priority, $msg);
 703 }
 704
 705 function common_debug($msg, $filename=NULL) {
 706         if ($filename) {
 707                 common_log(LOG_DEBUG, basename($filename).' - '.$msg);
 708         } else {
 709                 common_log(LOG_DEBUG, $msg);
 710         }
 711 }
 712
 713 function common_valid_http_url($url) {
 714         return Validate::uri($url, array('allowed_schemes' => array('http', 'https')));
 715 }
 716
 717 function common_valid_tag($tag) {
 718         if (preg_match('/^tag:(.*?),(\d{4}(-\d{2}(-\d{2})?)?):(.*)$/', $tag, $matches)) {
 719                 return (Validate::email($matches[1]) ||
 720                                 preg_match('/^([\w-\.]+)$/', $matches[1]));
 721         }
 722         return false;
 723 }
 724
 725 # Does a little before-after block for next/prev page
 726
 727 function common_pagination($have_before, $have_after, $page, $action, $args=NULL) {
 728
 729         if ($have_before || $have_after) {
 730                 common_element_start('div', array('id' => 'pagination'));
 731                 common_element_start('ul', array('id' => 'nav_pagination'));
 732         }
 733
 734         if ($have_before) {
 735                 $pargs = array('page' => $page-1);
 736                 $newargs = ($args) ? array_merge($args,$pargs) : $pargs;
 737
 738                 common_element_start('li', 'before');
 739                 common_element('a', array('href' => common_local_url($action, $newargs)),
 740                                            _t('« Before'));
 741                 common_element_end('li');
 742         }
 743
 744         if ($have_after) {
 745                 $pargs = array('page' => $page+1);
 746                 $newargs = ($args) ? array_merge($args,$pargs) : $pargs;
 747                 common_element_start('li', 'after');
 748                 common_element('a', array('href' => common_local_url($action, $newargs)),
 749                                                    _t('After »'));
 750                 common_element_end('li');
 751         }
 752
 753         if ($have_before || $have_after) {
 754                 common_element_end('ul');
 755                 common_element_end('div');
 756         }
 757 }
 758
 759 /* Following functions are copied from MediaWiki GlobalFunctions.php
 760  * and written by Evan Prodromou. */
 761
 762 function common_accept_to_prefs($accept, $def = '*/*') {
 763         # No arg means accept anything (per HTTP spec)
 764         if(!$accept) {
 765                 return array($def => 1);
 766         }
 767
 768         $prefs = array();
 769
 770         $parts = explode(',', $accept);
 771
 772         foreach($parts as $part) {
 773                 # FIXME: doesn't deal with params like 'text/html; level=1'
 774                 @list($value, $qpart) = explode(';', $part);
 775                 $match = array();
 776                 if(!isset($qpart)) {
 777                         $prefs[$value] = 1;
 778                 } elseif(preg_match('/q\s*=\s*(\d*\.\d+)/', $qpart, $match)) {
 779                         $prefs[$value] = $match[1];
 780                 }
 781         }
 782
 783         return $prefs;
 784 }
 785
 786 function common_mime_type_match($type, $avail) {
 787         if(array_key_exists($type, $avail)) {
 788                 return $type;
 789         } else {
 790                 $parts = explode('/', $type);
 791                 if(array_key_exists($parts[0] . '/*', $avail)) {
 792                         return $parts[0] . '/*';
 793                 } elseif(array_key_exists('*/*', $avail)) {
 794                         return '*/*';
 795                 } else {
 796                         return NULL;
 797                 }
 798         }
 799 }
 800
 801 function common_negotiate_type($cprefs, $sprefs) {
 802         $combine = array();
 803
 804         foreach(array_keys($sprefs) as $type) {
 805                 $parts = explode('/', $type);
 806                 if($parts[1] != '*') {
 807                         $ckey = common_mime_type_match($type, $cprefs);
 808                         if($ckey) {
 809                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
 810                         }
 811                 }
 812         }
 813
 814         foreach(array_keys($cprefs) as $type) {
 815                 $parts = explode('/', $type);
 816                 if($parts[1] != '*' && !array_key_exists($type, $sprefs)) {
 817                         $skey = common_mime_type_match($type, $sprefs);
 818                         if($skey) {
 819                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
 820                         }
 821                 }
 822         }
 823
 824         $bestq = 0;
 825         $besttype = NULL;
 826
 827         foreach(array_keys($combine) as $type) {
 828                 if($combine[$type] > $bestq) {
 829                         $besttype = $type;
 830                         $bestq = $combine[$type];
 831                 }
 832         }
 833
 834         return $besttype;
 835 }
 836
 837 function common_config($main, $sub) {
 838         global $config;
 839         return $config[$main][$sub];
 840 }