mod/chat/chatd.php

   1 <?php
   2 // This file is part of Moodle - http://moodle.org/
   3 //
   4 // Moodle is free software: you can redistribute it and/or modify
   5 // it under the terms of the GNU General Public License as published by
   6 // the Free Software Foundation, either version 3 of the License, or
   7 // (at your option) any later version.
   8 //
   9 // Moodle is distributed in the hope that it will be useful,
  10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 // GNU General Public License for more details.
  13 //
  14 // You should have received a copy of the GNU General Public License
  15 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  16
  17 /**
  18  * Chat daemon
  19  *
  20  * @package    mod_chat
  21  * @copyright  1999 onwards Martin Dougiamas  {@link http://moodle.com}
  22  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  23  */
  24
  25 define('CLI_SCRIPT', true);
  26
  27 require(__DIR__.'/../../config.php');
  28 require_once($CFG->dirroot . '/mod/chat/lib.php');
  29
  30 // Browser quirks.
  31 define('QUIRK_CHUNK_UPDATE', 0x0001);
  32
  33 // Connection telltale.
  34 define('CHAT_CONNECTION',           0x10);
  35 // Connections: Incrementing sequence, 0x10 to 0x1f.
  36 define('CHAT_CONNECTION_CHANNEL',   0x11);
  37
  38 // Sidekick telltale.
  39 define('CHAT_SIDEKICK',             0x20);
  40 // Sidekicks: Incrementing sequence, 0x21 to 0x2f.
  41 define('CHAT_SIDEKICK_USERS',       0x21);
  42 define('CHAT_SIDEKICK_MESSAGE',     0x22);
  43 define('CHAT_SIDEKICK_BEEP',        0x23);
  44
  45 $phpversion = phpversion();
  46 echo 'Moodle chat daemon v1.0 on PHP '.$phpversion."\n\n";
  47
  48 // Set up all the variables we need.
  49
  50 // The $CFG variables are now defined in database by chat/lib.php.
  51
  52 $_SERVER['PHP_SELF']        = 'dummy';
  53 $_SERVER['SERVER_NAME']     = 'dummy';
  54 $_SERVER['HTTP_USER_AGENT'] = 'dummy';
  55
  56 $_SERVER['SERVER_NAME'] = $CFG->chat_serverhost;
  57 $_SERVER['PHP_SELF']    = "http://$CFG->chat_serverhost:$CFG->chat_serverport/mod/chat/chatd.php";
  58
  59 core_php_time_limit::raise(0);
  60 error_reporting(E_ALL);
  61
  62 function chat_empty_connection() {
  63     return array('sid' => null, 'handle' => null, 'ip' => null, 'port' => null, 'groupid' => null);
  64 }
  65
  66 class ChatConnection {
  67     // Chat-related info.
  68     public $sid  = null;
  69     public $type = null;
  70
  71     // PHP-level info.
  72     public $handle = null;
  73
  74     // TCP/IP.
  75     public $ip     = null;
  76     public $port   = null;
  77
  78     public function __construct($resource) {
  79         $this->handle = $resource;
  80         @socket_getpeername($this->handle, $this->ip, $this->port);
  81     }
  82 }
  83
  84 class ChatDaemon {
  85     public $_resetsocket       = false;
  86     public $_readytogo         = false;
  87     public $_logfile           = false;
  88     public $_trace_to_console  = true;
  89     public $_trace_to_stdout   = true;
  90     public $_logfile_name      = 'chatd.log';
  91     public $_last_idle_poll    = 0;
  92
  93     public $connectionsunidentified  = array(); // Connections not identified yet.
  94     public $connectionsside = array(); // Sessions with sidekicks waiting for the main connection to be processed.
  95     public $connectionshalf = array(); // Sessions that have valid connections but not all of them.
  96     public $connectionssets = array(); // Sessions with complete connection sets.
  97     public $setsinfo = array(); // Keyed by sessionid exactly like conn_sets, one of these for each of those.
  98     public $chatrooms = array(); // Keyed by chatid, holding arrays of data.
  99
 100     // IMPORTANT: $connectionssets, $setsinfo and $chatrooms must remain synchronized!
 101     //            Pay extra attention when you write code that affects any of them!
 102
 103     public function __construct() {
 104         $this->_trace_level         = E_ALL ^ E_USER_NOTICE;
 105         $this->_pcntl_exists        = function_exists('pcntl_fork');
 106         $this->_time_rest_socket    = 20;
 107         $this->_beepsoundsrc        = $GLOBALS['CFG']->wwwroot.'/mod/chat/beep.mp3';
 108         $this->_freq_update_records = 20;
 109         $this->_freq_poll_idle_chat = $GLOBALS['CFG']->chat_old_ping;
 110         $this->_stdout = fopen('php://stdout', 'w');
 111         if ($this->_stdout) {
 112             // Avoid double traces for everything.
 113             $this->_trace_to_console = false;
 114         }
 115     }
 116
 117     public function error_handler ($errno, $errmsg, $filename, $linenum, $vars) {
 118         // Checks if an error needs to be suppressed due to @.
 119         if (error_reporting() != 0) {
 120             $this->trace($errmsg.' on line '.$linenum, $errno);
 121         }
 122         return true;
 123     }
 124
 125     public function poll_idle_chats($now) {
 126         $this->trace('Polling chats to detect disconnected users');
 127         if (!empty($this->chatrooms)) {
 128             foreach ($this->chatrooms as $chatid => $chatroom) {
 129                 if (!empty($chatroom['users'])) {
 130                     foreach ($chatroom['users'] as $sessionid => $userid) {
 131                         // We will be polling each user as required.
 132                         $this->trace('...shall we poll '.$sessionid.'?');
 133                         if (!empty($this->sets_info[$sessionid]) && isset($this->sets_info[$sessionid]['chatuser']) &&
 134                                 // Having tried to exclude race conditions as already done in user_lazy_update()
 135                                 // please do the real job by checking the last poll.
 136                                 ($this->sets_info[$sessionid]['chatuser']->lastmessageping < $this->_last_idle_poll)) {
 137                             $this->trace('YES!');
 138                             // This user hasn't been polled since his last message.
 139                             $result = $this->write_data($this->conn_sets[$sessionid][CHAT_CONNECTION_CHANNEL], '<!-- poll -->');
 140                             if ($result === false) {
 141                                 // User appears to have disconnected.
 142                                 $this->disconnect_session($sessionid);
 143                             }
 144                         }
 145                     }
 146                 }
 147             }
 148         }
 149         $this->_last_idle_poll = $now;
 150     }
 151
 152     public function query_start() {
 153         return $this->_readytogo;
 154     }
 155
 156     public function trace($message, $level = E_USER_NOTICE) {
 157         $severity = '';
 158
 159         switch($level) {
 160             case E_USER_WARNING:
 161                 $severity = '*IMPORTANT* ';
 162                 break;
 163             case E_USER_ERROR:
 164                 $severity = ' *CRITICAL* ';
 165                 break;
 166             case E_NOTICE:
 167             case E_WARNING:
 168                 $severity = ' *CRITICAL* [php] ';
 169                 break;
 170         }
 171
 172         $date = date('[Y-m-d H:i:s] ');
 173         $message = $date.$severity.$message."\n";
 174
 175         if ($this->_trace_level & $level) {
 176             // It is accepted for output.
 177
 178             // Error-class traces go to STDERR too.
 179             if ($level & E_USER_ERROR) {
 180                 fwrite(STDERR, $message);
 181             }
 182
 183             // Emit the message to wherever we should.
 184             if ($this->_trace_to_stdout) {
 185                 fwrite($this->_stdout, $message);
 186                 fflush($this->_stdout);
 187             }
 188             if ($this->_trace_to_console) {
 189                 echo $message;
 190                 flush();
 191             }
 192             if ($this->_logfile) {
 193                 fwrite($this->_logfile, $message);
 194                 fflush($this->_logfile);
 195             }
 196         }
 197     }
 198
 199     public function write_data($connection, $text) {
 200         $written = @socket_write($connection, $text, strlen($text));
 201         if ($written === false) {
 202             return false;
 203         }
 204         return true;
 205     }
 206
 207     public function user_lazy_update($sessionid) {
 208         global $DB;
 209
 210         if (empty($this->sets_info[$sessionid])) {
 211             $this->trace('user_lazy_update() called for an invalid SID: '.$sessionid, E_USER_WARNING);
 212             return false;
 213         }
 214
 215         // Does promote_final() already finish its job?
 216         if (!isset($this->sets_info[$sessionid]['lastinfocommit'])) {
 217             return false;
 218         }
 219
 220         $now = time();
 221
 222         // We 'll be cheating a little, and NOT updating the record data as
 223         // often as we can, so that we save on DB queries (imagine MANY users).
 224         if ($now - $this->sets_info[$sessionid]['lastinfocommit'] > $this->_freq_update_records) {
 225             // Commit to permanent storage.
 226             $this->sets_info[$sessionid]['lastinfocommit'] = $now;
 227             $DB->update_record('chat_users', $this->sets_info[$sessionid]['chatuser']);
 228         }
 229         return true;
 230     }
 231
 232     public function get_user_window($sessionid) {
 233         global $CFG, $OUTPUT;
 234
 235         static $str;
 236
 237         $info = &$this->sets_info[$sessionid];
 238
 239         $timenow = time();
 240
 241         if (empty($str)) {
 242             $str = new stdClass();
 243             $str->idle  = get_string("idle", "chat");
 244             $str->beep  = get_string("beep", "chat");
 245             $str->day   = get_string("day");
 246             $str->days  = get_string("days");
 247             $str->hour  = get_string("hour");
 248             $str->hours = get_string("hours");
 249             $str->min   = get_string("min");
 250             $str->mins  = get_string("mins");
 251             $str->sec   = get_string("sec");
 252             $str->secs  = get_string("secs");
 253             $str->years = get_string('years');
 254         }
 255
 256         ob_start();
 257         $refreshinval = $CFG->chat_refresh_userlist * 1000;
 258         echo <<<EOD
 259         <html><head>
 260         <meta http-equiv="refresh" content="$refreshinval">
 261         <style type="text/css"> img{border:0} </style>
 262         <script type="text/javascript">
 263         //<![CDATA[
 264         function openpopup(url,name,options,fullscreen) {
 265             fullurl = "$CFG->wwwroot" + url;
 266             windowobj = window.open(fullurl,name,options);
 267             if (fullscreen) {
 268                 windowobj.moveTo(0,0);
 269                 windowobj.resizeTo(screen.availWidth,screen.availHeight);
 270             }
 271             windowobj.focus();
 272             return false;
 273         }
 274         //]]>
 275         </script></head><body><table><tbody>
 276 EOD;
 277
 278         // Get the users from that chatroom.
 279         $users = $this->chatrooms[$info['chatid']]['users'];
 280
 281         foreach ($users as $usersessionid => $userid) {
 282             // Fetch each user's sessionid and then the rest of his data from $this->sets_info.
 283             $userinfo = $this->sets_info[$usersessionid];
 284
 285             $lastping = $timenow - $userinfo['chatuser']->lastmessageping;
 286
 287             echo '<tr><td width="35">';
 288
 289             $link = '/user/view.php?id='.$userinfo['user']->id.'&course='.$userinfo['courseid'];
 290             $anchortagcontents = $OUTPUT->user_picture($userinfo['user'], array('courseid' => $userinfo['courseid']));
 291
 292             $action = new popup_action('click', $link, 'user'.$userinfo['chatuser']->id);
 293             $anchortag = $OUTPUT->action_link($link, $anchortagcontents, $action);
 294
 295             echo $anchortag;
 296             echo "</td><td valign=\"center\">";
 297             echo "<p><font size=\"1\">";
 298             echo fullname($userinfo['user'])."<br />";
 299             echo "<font color=\"#888888\">$str->idle: ".format_time($lastping, $str)."</font> ";
 300             echo '<a target="empty" href="http://'.$CFG->chat_serverhost.':'.$CFG->chat_serverport.
 301                  '/?win=beep&amp;beep='.$userinfo['user']->id.
 302                  '&chat_sid='.$sessionid.'">'.$str->beep."</a>\n";
 303             echo "</font></p>";
 304             echo "<td></tr>";
 305         }
 306
 307         echo '</tbody></table>';
 308         echo "</body>\n</html>\n";
 309
 310         return ob_get_clean();
 311
 312     }
 313
 314     public function new_ufo_id() {
 315         static $id = 0;
 316         if ($id++ === 0x1000000) { // Cycling very very slowly to prevent overflow.
 317             $id = 0;
 318         }
 319         return $id;
 320     }
 321
 322     public function process_sidekicks($sessionid) {
 323         if (empty($this->conn_side[$sessionid])) {
 324             return true;
 325         }
 326         foreach ($this->conn_side[$sessionid] as $sideid => $sidekick) {
 327             // TODO: is this late-dispatch working correctly?
 328             $this->dispatch_sidekick($sidekick['handle'], $sidekick['type'], $sessionid, $sidekick['customdata']);
 329             unset($this->conn_side[$sessionid][$sideid]);
 330         }
 331         return true;
 332     }
 333
 334     public function dispatch_sidekick($handle, $type, $sessionid, $customdata) {
 335         global $CFG, $DB;
 336
 337         switch($type) {
 338             case CHAT_SIDEKICK_BEEP:
 339
 340                 // Incoming beep.
 341                 $msg = new stdClass;
 342                 $msg->chatid    = $this->sets_info[$sessionid]['chatid'];
 343                 $msg->userid    = $this->sets_info[$sessionid]['userid'];
 344                 $msg->groupid   = $this->sets_info[$sessionid]['groupid'];
 345                 $msg->issystem  = 0;
 346                 $msg->message   = 'beep '.$customdata['beep'];
 347                 $msg->timestamp = time();
 348
 349                 // Commit to DB.
 350                 chat_send_chatmessage($this->sets_info[$sessionid]['chatuser'], $msg->message, false,
 351                     $this->sets_info[$sessionid]['cm']);
 352
 353                 // OK, now push it out to all users.
 354                 $this->message_broadcast($msg, $this->sets_info[$sessionid]['user']);
 355
 356                 // Update that user's lastmessageping.
 357                 $this->sets_info[$sessionid]['chatuser']->lastping        = $msg->timestamp;
 358                 $this->sets_info[$sessionid]['chatuser']->lastmessageping = $msg->timestamp;
 359                 $this->user_lazy_update($sessionid);
 360
 361                 // We did our work, but before slamming the door on the poor browser
 362                 // show the courtesy of responding to the HTTP request. Otherwise, some
 363                 // browsers decide to get vengeance by flooding us with repeat requests.
 364
 365                 $header  = "HTTP/1.1 200 OK\n";
 366                 $header .= "Connection: close\n";
 367                 $header .= "Date: ".date('r')."\n";
 368                 $header .= "Server: Moodle\n";
 369                 $header .= "Content-Type: text/html; charset=utf-8\n";
 370                 $header .= "Last-Modified: ".gmdate("D, d M Y H:i:s")." GMT\n";
 371                 $header .= "Cache-Control: no-cache, must-revalidate\n";
 372                 $header .= "Expires: Wed, 4 Oct 1978 09:32:45 GMT\n";
 373                 $header .= "\n";
 374
 375                 // That's enough headers for one lousy dummy response.
 376                 $this->write_data($handle, $header);
 377                 // All done.
 378             break;
 379
 380             case CHAT_SIDEKICK_USERS:
 381                 // A request to paint a user window.
 382
 383                 $content = $this->get_user_window($sessionid);
 384
 385                 $header  = "HTTP/1.1 200 OK\n";
 386                 $header .= "Connection: close\n";
 387                 $header .= "Date: ".date('r')."\n";
 388                 $header .= "Server: Moodle\n";
 389                 $header .= "Content-Type: text/html; charset=utf-8\n";
 390                 $header .= "Last-Modified: ".gmdate("D, d M Y H:i:s")." GMT\n";
 391                 $header .= "Cache-Control: no-cache, must-revalidate\n";
 392                 $header .= "Expires: Wed, 4 Oct 1978 09:32:45 GMT\n";
 393                 $header .= "Content-Length: ".strlen($content)."\n";
 394
 395                 // The refresh value is 2 seconds higher than the configuration variable.
 396                 // This is because we are doing JS refreshes all the time.
 397                 // However, if the JS doesn't work for some reason, we still want to refresh once in a while.
 398                 $header .= "Refresh: ".(intval($CFG->chat_refresh_userlist) + 2).
 399                            "; url=http://$CFG->chat_serverhost:$CFG->chat_serverport/?win=users&".
 400                            "chat_sid=".$sessionid."\n";
 401                 $header .= "\n";
 402
 403                 // That's enough headers for one lousy dummy response.
 404                 $this->trace('writing users http response to handle '.$handle);
 405                 $this->write_data($handle, $header . $content);
 406
 407                 // Update that user's lastping.
 408                 $this->sets_info[$sessionid]['chatuser']->lastping = time();
 409                 $this->user_lazy_update($sessionid);
 410
 411             break;
 412
 413             case CHAT_SIDEKICK_MESSAGE:
 414                 // Incoming message.
 415
 416                 // Browser stupidity protection from duplicate messages.
 417                 $messageindex = intval($customdata['index']);
 418
 419                 if ($this->sets_info[$sessionid]['lastmessageindex'] >= $messageindex) {
 420                     // We have already broadcasted that!
 421                     break;
 422                 } else {
 423                     // Update our info.
 424                     $this->sets_info[$sessionid]['lastmessageindex'] = $messageindex;
 425                 }
 426
 427                 $msg = new stdClass;
 428                 $msg->chatid    = $this->sets_info[$sessionid]['chatid'];
 429                 $msg->userid    = $this->sets_info[$sessionid]['userid'];
 430                 $msg->groupid   = $this->sets_info[$sessionid]['groupid'];
 431                 $msg->issystem  = 0;
 432                 $msg->message   = urldecode($customdata['message']); // Have to undo the browser's encoding.
 433                 $msg->timestamp = time();
 434
 435                 if (empty($msg->message)) {
 436                     // Someone just hit ENTER, send them on their way.
 437                     break;
 438                 }
 439
 440                 // A slight hack to prevent malformed SQL inserts.
 441                 $origmsg = $msg->message;
 442                 $msg->message = $msg->message;
 443
 444                 // Commit to DB.
 445                 chat_send_chatmessage($this->sets_info[$sessionid]['chatuser'], $msg->message, false,
 446                     $this->sets_info[$sessionid]['cm']);
 447
 448                 // Undo the hack.
 449                 $msg->message = $origmsg;
 450
 451                 // OK, now push it out to all users.
 452                 $this->message_broadcast($msg, $this->sets_info[$sessionid]['user']);
 453
 454                 // Update that user's lastmessageping.
 455                 $this->sets_info[$sessionid]['chatuser']->lastping        = $msg->timestamp;
 456                 $this->sets_info[$sessionid]['chatuser']->lastmessageping = $msg->timestamp;
 457                 $this->user_lazy_update($sessionid);
 458
 459                 // We did our work, but before slamming the door on the poor browser
 460                 // show the courtesy of responding to the HTTP request. Otherwise, some
 461                 // browsers decide to get vengeance by flooding us with repeat requests.
 462
 463                 $header  = "HTTP/1.1 200 OK\n";
 464                 $header .= "Connection: close\n";
 465                 $header .= "Date: ".date('r')."\n";
 466                 $header .= "Server: Moodle\n";
 467                 $header .= "Content-Type: text/html; charset=utf-8\n";
 468                 $header .= "Last-Modified: ".gmdate("D, d M Y H:i:s")." GMT\n";
 469                 $header .= "Cache-Control: no-cache, must-revalidate\n";
 470                 $header .= "Expires: Wed, 4 Oct 1978 09:32:45 GMT\n";
 471                 $header .= "\n";
 472
 473                 // That's enough headers for one lousy dummy response.
 474                 $this->write_data($handle, $header);
 475
 476                 // All done.
 477             break;
 478         }
 479
 480         socket_shutdown($handle);
 481         socket_close($handle);
 482     }
 483
 484     public function promote_final($sessionid, $customdata) {
 485         global $DB;
 486
 487         if (isset($this->conn_sets[$sessionid])) {
 488             $this->trace('Set cannot be finalized: Session '.$sessionid.' is already active');
 489             return false;
 490         }
 491
 492         $chatuser = $DB->get_record('chat_users', array('sid' => $sessionid));
 493         if ($chatuser === false) {
 494             $this->dismiss_half($sessionid);
 495             return false;
 496         }
 497         $chat = $DB->get_record('chat', array('id' => $chatuser->chatid));
 498         if ($chat === false) {
 499             $this->dismiss_half($sessionid);
 500             return false;
 501         }
 502         $user = $DB->get_record('user', array('id' => $chatuser->userid));
 503         if ($user === false) {
 504             $this->dismiss_half($sessionid);
 505             return false;
 506         }
 507         $course = $DB->get_record('course', array('id' => $chat->course));
 508         if ($course === false) {
 509             $this->dismiss_half($sessionid);
 510             return false;
 511         }
 512         if (!($cm = get_coursemodule_from_instance('chat', $chat->id, $course->id))) {
 513             $this->dismiss_half($sessionid);
 514             return false;
 515         }
 516
 517         global $CHAT_HTMLHEAD_JS;
 518
 519         $this->conn_sets[$sessionid] = $this->conn_half[$sessionid];
 520
 521         // This whole thing needs to be purged of redundant info, and the
 522         // code base to follow suit. But AFTER development is done.
 523         $this->sets_info[$sessionid] = array(
 524             'lastinfocommit' => 0,
 525             'lastmessageindex' => 0,
 526             'course'    => $course,
 527             'courseid'  => $course->id,
 528             'chatuser'  => $chatuser,
 529             'chatid'    => $chat->id,
 530             'cm'        => $cm,
 531             'user'      => $user,
 532             'userid'    => $user->id,
 533             'groupid'   => $chatuser->groupid,
 534             'lang'      => $chatuser->lang,
 535             'quirks'    => $customdata['quirks']
 536         );
 537
 538         // If we know nothing about this chatroom, initialize it and add the user.
 539         if (!isset($this->chatrooms[$chat->id]['users'])) {
 540             $this->chatrooms[$chat->id]['users'] = array($sessionid => $user->id);
 541         } else {
 542             // Otherwise just add the user.
 543             $this->chatrooms[$chat->id]['users'][$sessionid] = $user->id;
 544         }
 545
 546         $header  = "HTTP/1.1 200 OK\n";
 547         $header .= "Connection: close\n";
 548         $header .= "Date: ".date('r')."\n";
 549         $header .= "Server: Moodle\n";
 550         $header .= "Content-Type: text/html; charset=utf-8\n";
 551         $header .= "Last-Modified: ".gmdate("D, d M Y H:i:s")." GMT\n";
 552         $header .= "Cache-Control: no-cache, must-revalidate\n";
 553         $header .= "Expires: Wed, 4 Oct 1978 09:32:45 GMT\n";
 554         $header .= "\n";
 555
 556         $this->dismiss_half($sessionid, false);
 557         $this->write_data($this->conn_sets[$sessionid][CHAT_CONNECTION_CHANNEL], $header . $CHAT_HTMLHEAD_JS);
 558         $this->trace('Connection accepted: '
 559                      .$this->conn_sets[$sessionid][CHAT_CONNECTION_CHANNEL]
 560                      .', SID: '
 561                      .$sessionid
 562                      .' UID: '
 563                      .$chatuser->userid
 564                      .' GID: '
 565                      .$chatuser->groupid, E_USER_WARNING);
 566
 567         // Finally, broadcast the "entered the chat" message.
 568
 569         $msg = new stdClass;
 570         $msg->chatid = $chatuser->chatid;
 571         $msg->userid = $chatuser->userid;
 572         $msg->groupid = $chatuser->groupid;
 573         $msg->issystem = 1;
 574         $msg->message = 'enter';
 575         $msg->timestamp = time();
 576
 577         chat_send_chatmessage($chatuser, $msg->message, true);
 578         $this->message_broadcast($msg, $this->sets_info[$sessionid]['user']);
 579
 580         return true;
 581     }
 582
 583     public function promote_ufo($handle, $type, $sessionid, $customdata) {
 584         if (empty($this->conn_ufo)) {
 585             return false;
 586         }
 587         foreach ($this->conn_ufo as $id => $ufo) {
 588             if ($ufo->handle == $handle) {
 589                 // OK, got the id of the UFO, but what is it?
 590
 591                 if ($type & CHAT_SIDEKICK) {
 592                     // Is the main connection ready?
 593                     if (isset($this->conn_sets[$sessionid])) {
 594                         // Yes, so dispatch this sidekick now and be done with it.
 595                         $this->dispatch_sidekick($handle, $type, $sessionid, $customdata);
 596                         $this->dismiss_ufo($handle, false);
 597                     } else {
 598                         // No, so put it in the waiting list.
 599                         $this->trace('sidekick waiting');
 600                         $this->conn_side[$sessionid][] = array('type' => $type, 'handle' => $handle, 'customdata' => $customdata);
 601                     }
 602                     return true;
 603                 }
 604
 605                 // If it's not a sidekick, at this point it can only be da man.
 606
 607                 if ($type & CHAT_CONNECTION) {
 608                     // This forces a new connection right now.
 609                     $this->trace('Incoming connection from '.$ufo->ip.':'.$ufo->port);
 610
 611                     // Do we have such a connection active?
 612                     if (isset($this->conn_sets[$sessionid])) {
 613                         // Yes, so regrettably we cannot promote you.
 614                         $this->trace('Connection rejected: session '.$sessionid.' is already final');
 615                         $this->dismiss_ufo($handle, true, 'Your SID was rejected.');
 616                         return false;
 617                     }
 618
 619                     // Join this with what we may have already.
 620                     $this->conn_half[$sessionid][$type] = $handle;
 621
 622                     // Do the bookkeeping.
 623                     $this->promote_final($sessionid, $customdata);
 624
 625                     // It's not a UFO anymore.
 626                     $this->dismiss_ufo($handle, false);
 627
 628                     // Dispatch waiting sidekicks.
 629                     $this->process_sidekicks($sessionid);
 630
 631                     return true;
 632                 }
 633             }
 634         }
 635         return false;
 636     }
 637
 638     public function dismiss_half($sessionid, $disconnect = true) {
 639         if (!isset($this->conn_half[$sessionid])) {
 640             return false;
 641         }
 642         if ($disconnect) {
 643             foreach ($this->conn_half[$sessionid] as $handle) {
 644                 @socket_shutdown($handle);
 645                 @socket_close($handle);
 646             }
 647         }
 648         unset($this->conn_half[$sessionid]);
 649         return true;
 650     }
 651
 652     public function dismiss_set($sessionid) {
 653         if (!empty($this->conn_sets[$sessionid])) {
 654             foreach ($this->conn_sets[$sessionid] as $handle) {
 655                 // Since we want to dismiss this, don't generate any errors if it's dead already.
 656                 @socket_shutdown($handle);
 657                 @socket_close($handle);
 658             }
 659         }
 660         $chatroom = $this->sets_info[$sessionid]['chatid'];
 661         $userid   = $this->sets_info[$sessionid]['userid'];
 662         unset($this->conn_sets[$sessionid]);
 663         unset($this->sets_info[$sessionid]);
 664         unset($this->chatrooms[$chatroom]['users'][$sessionid]);
 665         $this->trace('Removed all traces of user with session '.$sessionid, E_USER_NOTICE);
 666         return true;
 667     }
 668
 669     public function dismiss_ufo($handle, $disconnect = true, $message = null) {
 670         if (empty($this->conn_ufo)) {
 671             return false;
 672         }
 673         foreach ($this->conn_ufo as $id => $ufo) {
 674             if ($ufo->handle == $handle) {
 675                 unset($this->conn_ufo[$id]);
 676                 if ($disconnect) {
 677                     if (!empty($message)) {
 678                         $this->write_data($handle, $message."\n\n");
 679                     }
 680                     socket_shutdown($handle);
 681                     socket_close($handle);
 682                 }
 683                 return true;
 684             }
 685         }
 686         return false;
 687     }
 688
 689     public function conn_accept() {
 690         $readsocket = array($this->listen_socket);
 691         $write = null;
 692         $except = null;
 693         $changed = socket_select($readsocket, $write, $except, 0, 0);
 694
 695         if (!$changed) {
 696             return false;
 697         }
 698         $handle = socket_accept($this->listen_socket);
 699         if (!$handle) {
 700             return false;
 701         }
 702
 703         $newconn = new ChatConnection($handle);
 704         $id = $this->new_ufo_id();
 705         $this->conn_ufo[$id] = $newconn;
 706     }
 707
 708     public function conn_activity_ufo(&$handles) {
 709         $monitor = array();
 710         if (!empty($this->conn_ufo)) {
 711             foreach ($this->conn_ufo as $ufoid => $ufo) {
 712                 // Avoid socket_select() warnings by preventing the check over invalid resources.
 713                 if (is_resource($ufo->handle)) {
 714                     $monitor[$ufoid] = $ufo->handle;
 715                 } else {
 716                     $this->dismiss_ufo($ufo->handle, false);
 717                 }
 718             }
 719         }
 720
 721         if (empty($monitor)) {
 722             $handles = array();
 723             return 0;
 724         }
 725
 726         $a = null;
 727         $b = null;
 728         $retval = socket_select($monitor, $a, $b, null);
 729         $handles = $monitor;
 730
 731         return $retval;
 732     }
 733
 734     public function message_broadcast($message, $sender) {
 735
 736         if (empty($this->conn_sets)) {
 737             return true;
 738         }
 739
 740         $now = time();
 741
 742         // First of all, mark this chatroom as having had activity now.
 743         $this->chatrooms[$message->chatid]['lastactivity'] = $now;
 744
 745         foreach ($this->sets_info as $sessionid => $info) {
 746             // We need to get handles from users that are in the same chatroom, same group.
 747             if ($info['chatid'] == $message->chatid &&
 748               ($info['groupid'] == $message->groupid || $message->groupid == 0)) {
 749
 750                 // Simply give them the message.
 751                 $output = chat_format_message_manually($message, $info['courseid'], $sender, $info['user']);
 752                 if ($output !== false) {
 753                     $this->trace('Delivering message "'.$output->text.'" to ' .
 754                         $this->conn_sets[$sessionid][CHAT_CONNECTION_CHANNEL]);
 755
 756                     if ($output->beep) {
 757                         $playscript = '(function() { var audioElement = document.createElement("audio");' . "\n";
 758                         $playscript .= 'audioElement.setAttribute("src", "'.$this->_beepsoundsrc.'");' . "\n";
 759                         $playscript .= 'audioElement.play(); })();' . "\n";
 760                         $this->write_data($this->conn_sets[$sessionid][CHAT_CONNECTION_CHANNEL],
 761                                           '<script>' . $playscript . '</script>');
 762                     }
 763
 764                     if ($info['quirks'] & QUIRK_CHUNK_UPDATE) {
 765                         $output->html .= $GLOBALS['CHAT_DUMMY_DATA'];
 766                         $output->html .= $GLOBALS['CHAT_DUMMY_DATA'];
 767                         $output->html .= $GLOBALS['CHAT_DUMMY_DATA'];
 768                     }
 769
 770                     if (!$this->write_data($this->conn_sets[$sessionid][CHAT_CONNECTION_CHANNEL], $output->html)) {
 771                         $this->disconnect_session($sessionid);
 772                     }
 773                 }
 774             }
 775         }
 776     }
 777
 778     public function disconnect_session($sessionid) {
 779         global $DB;
 780
 781         $info = $this->sets_info[$sessionid];
 782
 783         $DB->delete_records('chat_users', array('sid' => $sessionid));
 784         $msg = new stdClass;
 785         $msg->chatid = $info['chatid'];
 786         $msg->userid = $info['userid'];
 787         $msg->groupid = $info['groupid'];
 788         $msg->issystem = 1;
 789         $msg->message = 'exit';
 790         $msg->timestamp = time();
 791
 792         $this->trace('User has disconnected, destroying uid '.$info['userid'].' with SID '.$sessionid, E_USER_WARNING);
 793         chat_send_chatmessage($info['chatuser'], $msg->message, true);
 794
 795         // IMPORTANT, kill him BEFORE broadcasting, otherwise we 'll get infinite recursion!
 796         $latesender = $info['user'];
 797         $this->dismiss_set($sessionid);
 798         $this->message_broadcast($msg, $latesender);
 799     }
 800
 801     public function fatal($message) {
 802         $message .= "\n";
 803         if ($this->_logfile) {
 804             $this->trace($message, E_USER_ERROR);
 805         }
 806         echo "FATAL ERROR:: $message\n";
 807         die();
 808     }
 809
 810     public function init_sockets() {
 811         global $CFG;
 812
 813         $this->trace('Setting up sockets');
 814
 815         if (false === ($this->listen_socket = socket_create(AF_INET, SOCK_STREAM, 0))) {
 816             // Failed to create socket.
 817             $lasterr = socket_last_error();
 818             $this->fatal('socket_create() failed: '. socket_strerror($lasterr).' ['.$lasterr.']');
 819         }
 820
 821         if (!socket_bind($this->listen_socket, $CFG->chat_serverip, $CFG->chat_serverport)) {
 822             // Failed to bind socket.
 823             $lasterr = socket_last_error();
 824             $this->fatal('socket_bind() failed: '. socket_strerror($lasterr).' ['.$lasterr.']');
 825         }
 826
 827         if (!socket_listen($this->listen_socket, $CFG->chat_servermax)) {
 828             // Failed to get socket to listen.
 829             $lasterr = socket_last_error();
 830             $this->fatal('socket_listen() failed: '. socket_strerror($lasterr).' ['.$lasterr.']');
 831         }
 832
 833         // Socket has been initialized and is ready.
 834         $this->trace('Socket opened on port '.$CFG->chat_serverport);
 835
 836         // What exactly does this do? http://www.unixguide.net/network/socketfaq/4.5.shtml is still not enlightening enough for me.
 837         socket_set_option($this->listen_socket, SOL_SOCKET, SO_REUSEADDR, 1);
 838         socket_set_nonblock($this->listen_socket);
 839     }
 840
 841     public function cli_switch($switch, $param = null) {
 842         switch($switch) { // LOL!
 843             case 'reset':
 844                 // Reset sockets.
 845                 $this->_resetsocket = true;
 846                 return false;
 847             case 'start':
 848                 // Start the daemon.
 849                 $this->_readytogo = true;
 850                 return false;
 851             break;
 852             case 'v':
 853                 // Verbose mode.
 854                 $this->_trace_level = E_ALL;
 855                 return false;
 856             break;
 857             case 'l':
 858                 // Use logfile.
 859                 if (!empty($param)) {
 860                     $this->_logfile_name = $param;
 861                 }
 862                 $this->_logfile = @fopen($this->_logfile_name, 'a+');
 863                 if ($this->_logfile == false) {
 864                     $this->fatal('Failed to open '.$this->_logfile_name.' for writing');
 865                 }
 866                 return false;
 867             default:
 868                 // Unrecognized.
 869                 $this->fatal('Unrecognized command line switch: '.$switch);
 870             break;
 871         }
 872         return false;
 873     }
 874
 875 }
 876
 877 $daemon = new ChatDaemon;
 878 set_error_handler(array($daemon, 'error_handler'));
 879
 880 // Check the parameters.
 881
 882 unset($argv[0]);
 883 $commandline = implode(' ', $argv);
 884 if (strpos($commandline, '-') === false) {
 885     if (!empty($commandline)) {
 886         // We cannot have received any meaningful parameters.
 887         $daemon->fatal('Garbage in command line');
 888     }
 889 } else {
 890     // Parse command line.
 891     $switches = preg_split('/(-{1,2}[a-zA-Z]+) */', $commandline, -1, PREG_SPLIT_NO_EMPTY | PREG_SPLIT_DELIM_CAPTURE);
 892
 893     // Taking advantage of the fact that $switches is indexed with incrementing numeric keys.
 894     // We will be using that to pass additional information to those switches who need it.
 895     $numswitches = count($switches);
 896
 897     // Fancy way to give a "hyphen" boolean flag to each "switch".
 898     $switches = array_map(function($x) {
 899         return array("str" => $x, "hyphen" => (substr($x, 0, 1) == "-"));
 900     }, $switches);
 901
 902     for ($i = 0; $i < $numswitches; ++$i) {
 903
 904         $switch = $switches[$i]['str'];
 905         $params = ($i == $numswitches - 1 ? null :
 906                                             ($switches[$i + 1]['hyphen'] ? null : trim($switches[$i + 1]['str']))
 907                   );
 908
 909         if (substr($switch, 0, 2) == '--') {
 910             // Double-hyphen switch.
 911             $daemon->cli_switch(strtolower(substr($switch, 2)), $params);
 912         } else if (substr($switch, 0, 1) == '-') {
 913             // Single-hyphen switch(es), may be more than one run together.
 914             $switch = substr($switch, 1); // Get rid of the "-".
 915             $len = strlen($switch);
 916             for ($j = 0; $j < $len; ++$j) {
 917                 $daemon->cli_switch(strtolower(substr($switch, $j, 1)), $params);
 918             }
 919         }
 920     }
 921 }
 922
 923 if (!$daemon->query_start()) {
 924     // For some reason we didn't start, so print out some info.
 925     echo 'Starts the Moodle chat socket server on port '.$CFG->chat_serverport;
 926     echo "\n\n";
 927     echo "Usage: chatd.php [parameters]\n\n";
 928     echo "Parameters:\n";
 929     echo "  --start         Starts the daemon\n";
 930     echo "  -v              Verbose mode (prints trivial information messages)\n";
 931     echo "  -l [logfile]    Log all messages to logfile (if not specified, chatd.log)\n";
 932     echo "Example:\n";
 933     echo "  chatd.php --start -l\n\n";
 934     die();
 935 }
 936
 937 if (!function_exists('socket_set_option')) {
 938     echo "Error: Function socket_set_option() does not exist.\n";
 939     echo "Possibly PHP has not been compiled with --enable-sockets.\n\n";
 940     die();
 941 }
 942
 943 $daemon->init_sockets();
 944
 945 $daemon->trace('Started Moodle chatd on port '.$CFG->chat_serverport.', listening socket '.$daemon->listen_socket, E_USER_WARNING);
 946
 947 // Clear the decks of old stuff.
 948 $DB->delete_records('chat_users', array('version' => 'sockets'));
 949
 950 while (true) {
 951     $active = array();
 952
 953     // First of all, let's see if any of our UFOs have identified itself.
 954     if ($daemon->conn_activity_ufo($active)) {
 955         foreach ($active as $handle) {
 956             $readsocket = array($handle);
 957             $write = null;
 958             $except = null;
 959             $changed = socket_select($readsocket, $write, $except, 0, 0);
 960
 961             if ($changed > 0) {
 962                 // Let's see what it has to say.
 963
 964                 $data = socket_read($handle, 2048); // Should be more than 512 to prevent empty pages and repeated messages!
 965                 if (empty($data)) {
 966                     continue;
 967                 }
 968
 969                 if (strlen($data) == 2048) { // If socket_read has more data, ignore all data.
 970                     $daemon->trace('UFO with '.$handle.': Data too long; connection closed', E_USER_WARNING);
 971                     $daemon->dismiss_ufo($handle, true, 'Data too long; connection closed');
 972                     continue;
 973                 }
 974
 975                 // Ignore desktop browser fake "favorite icon" requests.
 976                 if (strpos($data, 'GET /favicon.ico HTTP') === 0) {
 977                     // Known malformed data, drop it without any further notice.
 978                     continue;
 979                 }
 980
 981                 if (!preg_match('/win=(chat|users|message|beep).*&chat_sid=([a-zA-Z0-9]*) HTTP/', $data, $info)) {
 982                     // Malformed data.
 983                     $daemon->trace('UFO with '.$handle.': Request with malformed data; connection closed', E_USER_WARNING);
 984                     $daemon->dismiss_ufo($handle, true, 'Request with malformed data; connection closed');
 985                     continue;
 986                 }
 987
 988                 $type      = $info[1];
 989                 $sessionid = $info[2];
 990
 991                 $customdata = array();
 992
 993                 switch($type) {
 994                     case 'chat':
 995                         $type = CHAT_CONNECTION_CHANNEL;
 996                         $customdata['quirks'] = 0;
 997                         if (strpos($data, 'Safari')) {
 998                             $daemon->trace('Safari identified...', E_USER_WARNING);
 999                             $customdata['quirks'] += QUIRK_CHUNK_UPDATE;
1000                         }
1001                     break;
1002                     case 'users':
1003                         $type = CHAT_SIDEKICK_USERS;
1004                     break;
1005                     case 'beep':
1006                         $type = CHAT_SIDEKICK_BEEP;
1007                         if (!preg_match('/beep=([^&]*)[& ]/', $data, $info)) {
1008                             $daemon->trace('Beep sidekick did not contain a valid userid', E_USER_WARNING);
1009                             $daemon->dismiss_ufo($handle, true, 'Request with malformed data; connection closed');
1010                             continue 2;
1011                         } else {
1012                             $customdata = array('beep' => intval($info[1]));
1013                         }
1014                     break;
1015                     case 'message':
1016                         $type = CHAT_SIDEKICK_MESSAGE;
1017                         if (!preg_match('/chat_message=([^&]*)[& ]chat_msgidnr=([^&]*)[& ]/', $data, $info)) {
1018                             $daemon->trace('Message sidekick did not contain a valid message', E_USER_WARNING);
1019                             $daemon->dismiss_ufo($handle, true, 'Request with malformed data; connection closed');
1020                             continue 2;
1021                         } else {
1022                             $customdata = array('message' => $info[1], 'index' => $info[2]);
1023                         }
1024                     break;
1025                     default:
1026                         $daemon->trace('UFO with '.$handle.': Request with unknown type; connection closed', E_USER_WARNING);
1027                         $daemon->dismiss_ufo($handle, true, 'Request with unknown type; connection closed');
1028                         continue 2;
1029                     break;
1030                 }
1031
1032                 // OK, now we know it's something good. Promote it and pass it all the data it needs.
1033                 $daemon->promote_ufo($handle, $type, $sessionid, $customdata);
1034                 continue;
1035             }
1036         }
1037     }
1038
1039     $now = time();
1040
1041     // Clean up chatrooms with no activity as required.
1042     if ($now - $daemon->_last_idle_poll >= $daemon->_freq_poll_idle_chat) {
1043         $daemon->poll_idle_chats($now);
1044     }
1045
1046     // Finally, accept new connections.
1047     $daemon->conn_accept();
1048
1049     usleep($daemon->_time_rest_socket);
1050 }
1051
1052 @socket_shutdown($daemon->listen_socket, 0);
1053 die("\n\n-- terminated --\n");
1054