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_start('p', 'laconica');
 209         common_text(_t('This site is running the '));
 210         common_element('a', array('class' => 'software',
 211                                                           href => 'http://laconi.ca/'),
 212                                    'Laconica');
 213         common_text(_t('microblogging tool, version ' . LACONICA_VERSION . ', available under the '));
 214         common_element('a', array(href => 'http://www.fsf.org/licensing/licenses/agpl-3.0.html'),
 215                                    'GNU Affero General Public License');
 216         common_text(_t('.'));
 217         common_element_end('p');
 218         common_element('img', array('id' => 'cc',
 219                                                                 'src' => $config['license']['image'],
 220                                                                 'alt' => $config['license']['title']));
 221         common_element_start('p');
 222         common_text(_t('Unless otherwise specified, contents of this site are copyright by the contributors and available under the '));
 223         common_element('a', array('class' => 'license',
 224                                                           'rel' => 'license',
 225                                                           href => $config['license']['url']),
 226                                    $config['license']['title']);
 227         common_text(_t('. Contributors should be attributed by full name or nickname.'));
 228         common_element_end('p');
 229         common_element_end('div');
 230         common_element_end('div');
 231         common_element_end('body');
 232         common_element_end('html');
 233         common_end_xml();
 234 }
 235
 236 function common_text($txt) {
 237         global $xw;
 238         $xw->text($txt);
 239 }
 240
 241 function common_raw($xml) {
 242         global $xw;
 243         $xw->writeRaw($xml);
 244 }
 245
 246 function common_nav_menu() {
 247         $user = common_current_user();
 248         common_element_start('ul', array('id' => 'nav'));
 249         if ($user) {
 250                 common_menu_item(common_local_url('all', array('nickname' => $user->nickname)),
 251                                                  _t('Home'));
 252         }
 253         common_menu_item(common_local_url('public'), _t('Public'));
 254         common_menu_item(common_local_url('doc', array('title' => 'help')),
 255                                          _t('Help'));
 256         if ($user) {
 257                 common_menu_item(common_local_url('profilesettings'),
 258                                                  _t('Settings'));
 259                 common_menu_item(common_local_url('logout'),
 260                                                  _t('Logout'));
 261         } else {
 262                 common_menu_item(common_local_url('login'), _t('Login'));
 263                 common_menu_item(common_local_url('register'), _t('Register'));
 264         }
 265         common_element_end('ul');
 266 }
 267
 268 function common_foot_menu() {
 269         common_element_start('ul', array('id' => 'nav_sub'));
 270         common_menu_item(common_local_url('doc', array('title' => 'about')),
 271                                          _t('About'));
 272         common_menu_item(common_local_url('doc', array('title' => 'privacy')),
 273                                          _t('Privacy'));
 274         common_menu_item(common_local_url('doc', array('title' => 'source')),
 275                                          _t('Source'));
 276         common_element_end('ul');
 277 }
 278
 279 function common_menu_item($url, $text, $title=NULL, $is_selected=false) {
 280         $lattrs = array();
 281         if ($is_selected) {
 282                 $lattrs['class'] = 'current';
 283         }
 284         common_element_start('li', $lattrs);
 285         $attrs['href'] = $url;
 286         if ($title) {
 287                 $attrs['title'] = $title;
 288         }
 289         common_element('a', $attrs, $text);
 290         common_element_end('li');
 291 }
 292
 293 function common_input($id, $label, $value=NULL,$instructions=NULL) {
 294         common_element_start('p');
 295         common_element('label', array('for' => $id), $label);
 296         $attrs = array('name' => $id,
 297                                    'type' => 'text',
 298                                    'id' => $id);
 299         if ($value) {
 300                 $attrs['value'] = htmlspecialchars($value);
 301         }
 302         common_element('input', $attrs);
 303         if ($instructions) {
 304                 common_element('span', 'input_instructions', $instructions);
 305         }
 306         common_element_end('p');
 307 }
 308
 309 function common_hidden($id, $value) {
 310         common_element('input', array('name' => $id,
 311                                                                   'type' => 'hidden',
 312                                                                   'id' => $id,
 313                                                                   'value' => $value));
 314 }
 315
 316 function common_password($id, $label, $instructions=NULL) {
 317         common_element_start('p');
 318         common_element('label', array('for' => $id), $label);
 319         $attrs = array('name' => $id,
 320                                    'type' => 'password',
 321                                    'id' => $id);
 322         common_element('input', $attrs);
 323         if ($instructions) {
 324                 common_element('span', 'input_instructions', $instructions);
 325         }
 326         common_element_end('p');
 327 }
 328
 329 function common_submit($id, $label) {
 330         global $xw;
 331         common_element_start('p');
 332         common_element('input', array('type' => 'submit',
 333                                                                   'id' => $id,
 334                                                                   'name' => $id,
 335                                                                   'value' => $label));
 336         common_element_end('p');
 337 }
 338
 339 function common_textarea($id, $label, $content=NULL, $instructions=NULL) {
 340         common_element_start('p');
 341         common_element('label', array('for' => $id), $label);
 342         common_element('textarea', array('rows' => 3,
 343                                                                          'cols' => 40,
 344                                                                          'name' => $id,
 345                                                                          'id' => $id),
 346                                    ($content) ? $content : ' ');
 347         if ($instructions) {
 348                 common_element('span', 'input_instructions', $instructions);
 349         }
 350         common_element_end('p');
 351 }
 352
 353 # salted, hashed passwords are stored in the DB
 354
 355 function common_munge_password($id, $password) {
 356         return md5($id . $password);
 357 }
 358
 359 # check if a username exists and has matching password
 360 function common_check_user($nickname, $password) {
 361         $user = User::staticGet('nickname', $nickname);
 362         if (is_null($user)) {
 363                 return false;
 364         } else {
 365                 return (0 == strcmp(common_munge_password($password, $user->id),
 366                                                         $user->password));
 367         }
 368 }
 369
 370 # is the current user logged in?
 371 function common_logged_in() {
 372         return (!is_null(common_current_user()));
 373 }
 374
 375 function common_have_session() {
 376         return (0 != strcmp(session_id(), ''));
 377 }
 378
 379 function common_ensure_session() {
 380         if (!common_have_session()) {
 381                 @session_start();
 382         }
 383 }
 384
 385 function common_set_user($nickname) {
 386         if (is_null($nickname) && common_have_session()) {
 387                 unset($_SESSION['userid']);
 388                 return true;
 389         } else {
 390                 $user = User::staticGet('nickname', $nickname);
 391                 if ($user) {
 392                         common_ensure_session();
 393                         $_SESSION['userid'] = $user->id;
 394                         return true;
 395                 } else {
 396                         return false;
 397                 }
 398         }
 399         return false;
 400 }
 401
 402 # who is the current user?
 403 function common_current_user() {
 404         static $user = NULL; # FIXME: global memcached
 405         if (is_null($user)) {
 406                 common_ensure_session();
 407                 $id = $_SESSION['userid'];
 408                 if ($id) {
 409                         $user = User::staticGet($id);
 410                 }
 411         }
 412         return $user;
 413 }
 414
 415 # get canonical version of nickname for comparison
 416 function common_canonical_nickname($nickname) {
 417         # XXX: UTF-8 canonicalization (like combining chars)
 418         return strtolower($nickname);
 419 }
 420
 421 # get canonical version of email for comparison
 422 function common_canonical_email($email) {
 423         # XXX: canonicalize UTF-8
 424         # XXX: lcase the domain part
 425         return $email;
 426 }
 427
 428 define('URL_REGEX', '^|[ \t\r\n])((ftp|http|https|gopher|mailto|news|nntp|telnet|wais|file|prospero|aim|webcal):(([A-Za-z0-9$_.+!*(),;/?:@&~=-])|%[A-Fa-f0-9]{2}){2,}(#([a-zA-Z0-9][a-zA-Z0-9$_.+!*(),;/?:@&~=%-]*))?([A-Za-z0-9$_+!*();/?:~-]))');
 429
 430 function common_render_content($text, $notice) {
 431         $r = htmlspecialchars($text);
 432         $id = $notice->profile_id;
 433         $r = preg_replace('@https?://\S+@', '<a href="\0" class="extlink">\0</a>', $r);
 434         $r = preg_replace('/(^|\b)@([\w-]+)($|\b)/e', "'\\1@'.common_at_link($id, '\\2').'\\3'", $r);
 435         # XXX: # tags
 436         # XXX: machine tags
 437         return $r;
 438 }
 439
 440 function common_at_link($sender_id, $nickname) {
 441         # Try to find profiles this profile is subscribed to that have this nickname
 442         $recipient = new Profile();
 443         # XXX: chokety and bad
 444         $recipient->whereAdd('EXISTS (SELECT subscribed from subscription where subscriber = '.$sender_id.' and subscribed = id)', 'AND');
 445         $recipient->whereAdd('nickname = "' . trim($nickname) . '"', 'AND');
 446         if ($recipient->find(TRUE)) {
 447                 return '<a href="'.htmlspecialchars($recipient->profileurl).'" class="atlink tolistenee">'.$nickname.'</a>';
 448         }
 449         # Try to find profiles that listen to this profile and that have this nickname
 450         $recipient = new Profile();
 451         # XXX: chokety and bad
 452         $recipient->whereAdd('EXISTS (SELECT subscriber from subscription where subscribed = '.$sender_id.' and subscriber = id)', 'AND');
 453         $recipient->whereAdd('nickname = "' . trim($nickname) . '"', 'AND');
 454         if ($recipient->find(TRUE)) {
 455                 return '<a href="'.htmlspecialchars($recipient->profileurl).'" class="atlink tolistener">'.$nickname.'</a>';
 456         }
 457         # If this is a local user, try to find a local user with that nickname.
 458         $sender = User::staticGet($sender_id);
 459         if ($sender) {
 460                 $recipient_user = User::staticGet('nickname', $nickname);
 461                 if ($recipient_user) {
 462                         $recipient = $recipient->getProfile();
 463                         return '<a href="'.htmlspecialchars($recipient->profileurl).'" class="atlink usertouser">'.$nickname.'</a>';
 464                 }
 465         }
 466         # Otherwise, no links. @messages from local users to remote users,
 467         # or from remote users to other remote users, are just
 468         # outside our ability to make intelligent guesses about
 469         return $nickname;
 470 }
 471
 472 // where should the avatar go for this user?
 473
 474 function common_avatar_filename($id, $extension, $size=NULL, $extra=NULL) {
 475         global $config;
 476
 477         if ($size) {
 478                 return $id . '-' . $size . (($extra) ? ('-' . $extra) : '') . $extension;
 479         } else {
 480                 return $id . '-original' . (($extra) ? ('-' . $extra) : '') . $extension;
 481         }
 482 }
 483
 484 function common_avatar_path($filename) {
 485         global $config;
 486         return INSTALLDIR . '/avatar/' . $filename;
 487 }
 488
 489 function common_avatar_url($filename) {
 490         return common_path('avatar/'.$filename);
 491 }
 492
 493 function common_default_avatar($size) {
 494         static $sizenames = array(AVATAR_PROFILE_SIZE => 'profile',
 495                                                           AVATAR_STREAM_SIZE => 'stream',
 496                                                           AVATAR_MINI_SIZE => 'mini');
 497         return theme_path('default-avatar-'.$sizenames[$size].'.png');
 498 }
 499
 500 function common_local_url($action, $args=NULL) {
 501         global $config;
 502         if ($config['site']['fancy']) {
 503                 return common_fancy_url($action, $args);
 504         } else {
 505                 return common_simple_url($action, $args);
 506         }
 507 }
 508
 509 function common_fancy_url($action, $args=NULL) {
 510         switch (strtolower($action)) {
 511          case 'public':
 512                 if ($args && $args['page']) {
 513                         return common_path('?page=' . $args['page']);
 514                 } else {
 515                         return common_path('');
 516                 }
 517          case 'publicrss':
 518                 return common_path('rss');
 519          case 'doc':
 520                 return common_path('doc/'.$args['title']);
 521          case 'login':
 522          case 'logout':
 523          case 'register':
 524          case 'subscribe':
 525          case 'unsubscribe':
 526                 return common_path('main/'.$action);
 527          case 'avatar':
 528          case 'password':
 529                 return common_path('settings/'.$action);
 530          case 'profilesettings':
 531                 return common_path('settings/profile');
 532          case 'newnotice':
 533                 return common_path('notice/new');
 534          case 'shownotice':
 535                 return common_path('notice/'.$args['notice']);
 536          case 'xrds':
 537          case 'foaf':
 538                 return common_path($args['nickname'].'/'.$action);
 539          case 'subscriptions':
 540          case 'subscribed':
 541          case 'all':
 542                 if ($args && $args['page']) {
 543                         return common_path($args['nickname'].'/'.$action.'?page=' . $args['page']);
 544                 } else {
 545                         return common_path($args['nickname'].'/'.$action);
 546                 }
 547          case 'allrss':
 548                 return common_path($args['nickname'].'/all/rss');
 549          case 'userrss':
 550                 return common_path($args['nickname'].'/rss');
 551          case 'showstream':
 552                 if ($args && $args['page']) {
 553                         return common_path($args['nickname'].'?page=' . $args['page']);
 554                 } else {
 555                         return common_path($args['nickname']);
 556                 }
 557          default:
 558                 return common_simple_url($action, $args);
 559         }
 560 }
 561
 562 function common_simple_url($action, $args=NULL) {
 563         global $config;
 564         /* XXX: pretty URLs */
 565         $extra = '';
 566         if ($args) {
 567                 foreach ($args as $key => $value) {
 568                         $extra .= "&${key}=${value}";
 569                 }
 570         }
 571         return common_path("index.php?action=${action}${extra}");
 572 }
 573
 574 function common_path($relative) {
 575         global $config;
 576         $pathpart = ($config['site']['path']) ? $config['site']['path']."/" : '';
 577         return "http://".$config['site']['server'].'/'.$pathpart.$relative;
 578 }
 579
 580 function common_date_string($dt) {
 581         // XXX: do some sexy date formatting
 582         // return date(DATE_RFC822, $dt);
 583         return $dt;
 584 }
 585
 586 function common_date_w3dtf($dt) {
 587         $t = strtotime($dt);
 588         return date(DATE_W3C, $t);
 589 }
 590
 591 function common_redirect($url, $code=307) {
 592         static $status = array(301 => "Moved Permanently",
 593                                                    302 => "Found",
 594                                                    303 => "See Other",
 595                                                    307 => "Temporary Redirect");
 596         header("Status: ${code} $status[$code]");
 597         header("Location: $url");
 598         common_element('a', array('href' => $url), $url);
 599 }
 600
 601 function common_broadcast_notice($notice, $remote=false) {
 602         // XXX: optionally use a queue system like http://code.google.com/p/microapps/wiki/NQDQ
 603         if (!$remote) {
 604                 # Make sure we have the OMB stuff
 605                 require_once(INSTALLDIR.'/lib/omb.php');
 606                 omb_broadcast_remote_subscribers($notice);
 607         }
 608         // XXX: broadcast notices to Jabber
 609         // XXX: broadcast notices to SMS
 610         // XXX: broadcast notices to other IM
 611         return true;
 612 }
 613
 614 function common_broadcast_profile($profile) {
 615         // XXX: optionally use a queue system like http://code.google.com/p/microapps/wiki/NQDQ
 616         require_once(INSTALLDIR.'/lib/omb.php');
 617         omb_broadcast_profile($profile);
 618         // XXX: Other broadcasts...?
 619         return true;
 620 }
 621
 622 function common_profile_url($nickname) {
 623         return common_local_url('showstream', array('nickname' => $nickname));
 624 }
 625
 626 # Don't call if nobody's logged in
 627
 628 function common_notice_form() {
 629         $user = common_current_user();
 630         assert(!is_null($user));
 631         common_element_start('form', array('id' => 'status_form',
 632                                                                            'method' => 'POST',
 633                                                                            'action' => common_local_url('newnotice')));
 634         common_element_start('p');
 635         common_element('label', array('for' => 'status_update',
 636                                                                   'id' => 'status_label'),
 637                                    _t('What\'s up, ').$user->nickname.'?');
 638         common_element('textarea', array('id' => 'status_textarea',
 639                                                                          'name' => 'status_textarea'));
 640         common_element('input', array('id' => 'status_submit',
 641                                                                   'name' => 'status_submit',
 642                                                                   'type' => 'submit',
 643                                                                   'value' => _t('Send')));
 644         common_element_end('p');
 645         common_element_end('form');
 646 }
 647
 648 function common_mint_tag($extra) {
 649         global $config;
 650         return
 651           'tag:'.$config['tag']['authority'].','.
 652           $config['tag']['date'].':'.$config['tag']['prefix'].$extra;
 653 }
 654
 655 # Should make up a reasonable root URL
 656
 657 function common_root_url() {
 658         return common_path('');
 659 }
 660
 661 # returns $bytes bytes of random data as a hexadecimal string
 662 # "good" here is a goal and not a guarantee
 663
 664 function common_good_rand($bytes) {
 665         # XXX: use random.org...?
 666         if (file_exists('/dev/urandom')) {
 667                 return common_urandom($bytes);
 668         } else { # FIXME: this is probably not good enough
 669                 return common_mtrand($bytes);
 670         }
 671 }
 672
 673 function common_urandom($bytes) {
 674         $h = fopen('/dev/urandom', 'rb');
 675         # should not block
 676         $src = fread($h, $bytes);
 677         fclose($h);
 678         $enc = '';
 679         for ($i = 0; $i < $bytes; $i++) {
 680                 $enc .= sprintf("%02x", (ord($src[$i])));
 681         }
 682         return $enc;
 683 }
 684
 685 function common_mtrand($bytes) {
 686         $enc = '';
 687         for ($i = 0; $i < $bytes; $i++) {
 688                 $enc .= sprintf("%02x", mt_rand(0, 255));
 689         }
 690         return $enc;
 691 }
 692
 693 function common_set_returnto($url) {
 694         common_ensure_session();
 695         $_SESSION['returnto'] = $url;
 696 }
 697
 698 function common_get_returnto() {
 699         common_ensure_session();
 700         return $_SESSION['returnto'];
 701 }
 702
 703 function common_timestamp() {
 704         return date('YmdHis');
 705 }
 706
 707 // XXX: set up gettext
 708
 709 function _t($str) {
 710         return $str;
 711 }
 712
 713 function common_ensure_syslog() {
 714         static $initialized = false;
 715         if (!$initialized) {
 716                 global $config;
 717                 define_syslog_variables();
 718                 openlog($config['syslog']['appname'], 0, LOG_USER);
 719                 $initialized = true;
 720         }
 721 }
 722
 723 function common_log($priority, $msg, $filename=NULL) {
 724         common_ensure_syslog();
 725         syslog($priority, $msg);
 726 }
 727
 728 function common_debug($msg, $filename=NULL) {
 729         if ($filename) {
 730                 common_log(LOG_DEBUG, basename($filename).' - '.$msg);
 731         } else {
 732                 common_log(LOG_DEBUG, $msg);
 733         }
 734 }
 735
 736 function common_valid_http_url($url) {
 737         return Validate::uri($url, array('allowed_schemes' => array('http', 'https')));
 738 }
 739
 740 function common_valid_tag($tag) {
 741         if (preg_match('/^tag:(.*?),(\d{4}(-\d{2}(-\d{2})?)?):(.*)$/', $tag, $matches)) {
 742                 return (Validate::email($matches[1]) ||
 743                                 preg_match('/^([\w-\.]+)$/', $matches[1]));
 744         }
 745         return false;
 746 }
 747
 748 # Does a little before-after block for next/prev page
 749
 750 function common_pagination($have_before, $have_after, $page, $action, $args=NULL) {
 751
 752         if ($have_before || $have_after) {
 753                 common_element_start('div', array('id' => 'pagination'));
 754                 common_element_start('ul', array('id' => 'nav_pagination'));
 755         }
 756
 757         if ($have_before) {
 758                 $pargs = array('page' => $page-1);
 759                 $newargs = ($args) ? array_merge($args,$pargs) : $pargs;
 760
 761                 common_element_start('li', 'before');
 762                 common_element('a', array('href' => common_local_url($action, $newargs)),
 763                                            _t('« After'));
 764                 common_element_end('li');
 765         }
 766
 767         if ($have_after) {
 768                 $pargs = array('page' => $page+1);
 769                 $newargs = ($args) ? array_merge($args,$pargs) : $pargs;
 770                 common_element_start('li', 'after');
 771                 common_element('a', array('href' => common_local_url($action, $newargs)),
 772                                                    _t('Before »'));
 773                 common_element_end('li');
 774         }
 775
 776         if ($have_before || $have_after) {
 777                 common_element_end('ul');
 778                 common_element_end('div');
 779         }
 780 }
 781
 782 /* Following functions are copied from MediaWiki GlobalFunctions.php
 783  * and written by Evan Prodromou. */
 784
 785 function common_accept_to_prefs($accept, $def = '*/*') {
 786         # No arg means accept anything (per HTTP spec)
 787         if(!$accept) {
 788                 return array($def => 1);
 789         }
 790
 791         $prefs = array();
 792
 793         $parts = explode(',', $accept);
 794
 795         foreach($parts as $part) {
 796                 # FIXME: doesn't deal with params like 'text/html; level=1'
 797                 @list($value, $qpart) = explode(';', $part);
 798                 $match = array();
 799                 if(!isset($qpart)) {
 800                         $prefs[$value] = 1;
 801                 } elseif(preg_match('/q\s*=\s*(\d*\.\d+)/', $qpart, $match)) {
 802                         $prefs[$value] = $match[1];
 803                 }
 804         }
 805
 806         return $prefs;
 807 }
 808
 809 function common_mime_type_match($type, $avail) {
 810         if(array_key_exists($type, $avail)) {
 811                 return $type;
 812         } else {
 813                 $parts = explode('/', $type);
 814                 if(array_key_exists($parts[0] . '/*', $avail)) {
 815                         return $parts[0] . '/*';
 816                 } elseif(array_key_exists('*/*', $avail)) {
 817                         return '*/*';
 818                 } else {
 819                         return NULL;
 820                 }
 821         }
 822 }
 823
 824 function common_negotiate_type($cprefs, $sprefs) {
 825         $combine = array();
 826
 827         foreach(array_keys($sprefs) as $type) {
 828                 $parts = explode('/', $type);
 829                 if($parts[1] != '*') {
 830                         $ckey = common_mime_type_match($type, $cprefs);
 831                         if($ckey) {
 832                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
 833                         }
 834                 }
 835         }
 836
 837         foreach(array_keys($cprefs) as $type) {
 838                 $parts = explode('/', $type);
 839                 if($parts[1] != '*' && !array_key_exists($type, $sprefs)) {
 840                         $skey = common_mime_type_match($type, $sprefs);
 841                         if($skey) {
 842                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
 843                         }
 844                 }
 845         }
 846
 847         $bestq = 0;
 848         $besttype = NULL;
 849
 850         foreach(array_keys($combine) as $type) {
 851                 if($combine[$type] > $bestq) {
 852                         $besttype = $type;
 853                         $bestq = $combine[$type];
 854                 }
 855         }
 856
 857         return $besttype;
 858 }
 859
 860 function common_config($main, $sub) {
 861         global $config;
 862         return $config[$main][$sub];
 863 }