mod/chat/chatd.php

   1 #!/usr/bin/php -q
   2 <?php
   3
   4 // Browser quirks
   5 define('QUIRK_CHUNK_UPDATE', 0x0001);
   6
   7 // Connection telltale
   8 define('CHAT_CONNECTION',           0x10);
   9 // Connections: Incrementing sequence, 0x10 to 0x1f
  10 define('CHAT_CONNECTION_CHANNEL',   0x11);
  11
  12 // Sidekick telltale
  13 define('CHAT_SIDEKICK',             0x20);
  14 // Sidekicks: Incrementing sequence, 0x21 to 0x2f
  15 define('CHAT_SIDEKICK_USERS',       0x21);
  16 define('CHAT_SIDEKICK_MESSAGE',     0x22);
  17 define('CHAT_SIDEKICK_BEEP',        0x23);
  18
  19 $phpversion = phpversion();
  20 echo 'Moodle chat daemon v1.0 on PHP '.$phpversion." (\$Id$)\n\n";
  21
  22 /// Set up all the variables we need   /////////////////////////////////////
  23
  24 /// $CFG variables are now defined in database by chat/lib.php
  25
  26 $_SERVER['PHP_SELF']        = 'dummy';
  27 $_SERVER['SERVER_NAME']     = 'dummy';
  28 $_SERVER['HTTP_USER_AGENT'] = 'dummy';
  29
  30 $nomoodlecookie = true;
  31
  32 include('../../config.php');
  33 include('lib.php');
  34
  35 $_SERVER['SERVER_NAME'] = $CFG->chat_serverhost;
  36 $_SERVER['PHP_SELF']    = "http://$CFG->chat_serverhost:$CFG->chat_serverport/mod/chat/chatd.php";
  37
  38 $safemode = ini_get('safe_mode');
  39
  40 if($phpversion < '4.3') {
  41     die("Error: The Moodle chat daemon requires at least PHP version 4.3 to run.\n       Since your version is $phpversion, you have to upgrade.\n\n");
  42 }
  43 if(!empty($safemode)) {
  44     die("Error: Cannot run with PHP safe_mode = On. Turn off safe_mode in php.ini.\n");
  45 }
  46
  47 $passref = ini_get('allow_call_time_pass_reference');
  48 if(empty($passref)) {
  49     die("Error: Cannot run with PHP allow_call_time_pass_reference = Off. Turn on allow_call_time_pass_reference in php.ini.\n");
  50 }
  51
  52 @set_time_limit (0);
  53 set_magic_quotes_runtime(0);
  54 error_reporting(E_ALL);
  55
  56 function chat_empty_connection() {
  57     return array('sid' => NULL, 'handle' => NULL, 'ip' => NULL, 'port' => NULL, 'groupid' => NULL);
  58 }
  59
  60 class ChatConnection {
  61     // Chat-related info
  62     var $sid    = NULL;
  63     var $type   = NULL;
  64     //var $groupid        = NULL;
  65
  66     // PHP-level info
  67     var $handle = NULL;
  68
  69     // TCP/IP
  70     var $ip     = NULL;
  71     var $port   = NULL;
  72
  73     function ChatConnection($resource) {
  74         $this->handle = $resource;
  75         @socket_getpeername($this->handle, &$this->ip, &$this->port);
  76     }
  77 }
  78
  79 class ChatDaemon {
  80     var $_resetsocket       = false;
  81     var $_readytogo         = false;
  82     var $_logfile           = false;
  83     var $_trace_to_console  = true;
  84     var $_trace_to_stdout   = true;
  85     var $_logfile_name      = 'chatd.log';
  86     var $_last_idle_poll    = 0;
  87
  88     var $conn_ufo  = array();    // Connections not identified yet
  89     var $conn_side = array();    // Sessions with sidekicks waiting for the main connection to be processed
  90     var $conn_half = array();    // Sessions that have valid connections but not all of them
  91     var $conn_sets = array();    // Sessions with complete connection sets sets
  92     var $sets_info = array();    // Keyed by sessionid exactly like conn_sets, one of these for each of those
  93     var $chatrooms = array();    // Keyed by chatid, holding arrays of data
  94
  95     // IMPORTANT: $conn_sets, $sets_info and $chatrooms must remain synchronized!
  96     //            Pay extra attention when you write code that affects any of them!
  97
  98     function ChatDaemon() {
  99         $this->_trace_level         = E_ALL ^ E_USER_NOTICE;
 100         $this->_pcntl_exists        = function_exists('pcntl_fork');
 101         $this->_time_rest_socket    = 20;
 102         $this->_beepsoundsrc        = $GLOBALS['CFG']->wwwroot.'/mod/chat/beep.wav';
 103         $this->_freq_update_records = 20;
 104         $this->_freq_poll_idle_chat = $GLOBALS['CFG']->chat_old_ping;
 105         $this->_stdout = fopen('php://stdout', 'w');
 106         if($this->_stdout) {
 107             // Avoid double traces for everything
 108             $this->_trace_to_console = false;
 109         }
 110     }
 111
 112     function error_handler ($errno, $errmsg, $filename, $linenum, $vars) {
 113         // Checks if an error needs to be suppressed due to @
 114         if(error_reporting() != 0) {
 115             $this->trace($errmsg.' on line '.$linenum, $errno);
 116         }
 117         return true;
 118     }
 119
 120     function poll_idle_chats($now) {
 121         $this->trace('Polling chats to detect disconnected users');
 122         if(!empty($this->chatrooms)) {
 123             foreach($this->chatrooms as $chatid => $chatroom) {
 124                 if(!empty($chatroom['users'])) {
 125                     foreach($chatroom['users'] as $sessionid => $userid) {
 126                         // We will be polling each user as required
 127                         $this->trace('...shall we poll '.$sessionid.'?');
 128                         if($this->sets_info[$sessionid]['chatuser']->lastmessageping < $this->_last_idle_poll) {
 129                             $this->trace('YES!');
 130                             // This user hasn't been polled since his last message
 131                             if($this->write_data($this->conn_sets[$sessionid][CHAT_CONNECTION_CHANNEL], '<!-- poll -->') === false) {
 132                                 // User appears to have disconnected
 133                                 $this->disconnect_session($sessionid);
 134                             }
 135                         }
 136                     }
 137                 }
 138             }
 139         }
 140         $this->_last_idle_poll = $now;
 141     }
 142
 143     function query_start() {
 144         return $this->_readytogo;
 145     }
 146
 147     function trace($message, $level = E_USER_NOTICE) {
 148         $severity = '';
 149
 150         switch($level) {
 151             case E_USER_WARNING: $severity = '*IMPORTANT* '; break;
 152             case E_USER_ERROR:   $severity = ' *CRITICAL* '; break;
 153             case E_NOTICE:
 154             case E_WARNING:      $severity = ' *CRITICAL* [php] '; break;
 155         }
 156
 157         $date = date('[Y-m-d H:i:s] ');
 158         $message = $date.$severity.$message."\n";
 159
 160         if ($this->_trace_level & $level) {
 161             // It is accepted for output
 162
 163             // Error-class traces go to STDERR too
 164             if($level & E_USER_ERROR) {
 165                 fwrite(STDERR, $message);
 166             }
 167
 168             // Emit the message to wherever we should
 169             if($this->_trace_to_stdout) {
 170                 fwrite($this->_stdout, $message);
 171                 fflush($this->_stdout);
 172             }
 173             if($this->_trace_to_console) {
 174                 echo $message;
 175                 flush();
 176             }
 177             if($this->_logfile) {
 178                 fwrite($this->_logfile, $message);
 179                 fflush($this->_logfile);
 180             }
 181         }
 182     }
 183
 184     function write_data($connection, $text) {
 185         $written = @socket_write($connection, $text, strlen($text));
 186         if($written === false) {
 187             // $this->trace("socket_write() failed: reason: " . socket_strerror(socket_last_error($connection)));
 188             return false;
 189         }
 190         return true;
 191
 192         // Enclosing the above code inside this blocks makes sure that
 193         // "a socket write operation will not block". I 'm not so sure
 194         // if this is needed, as we have a nonblocking socket anyway.
 195         // If trouble starts to creep up, we 'll restore this.
 196 //        $check_socket = array($connection);
 197 //        $socket_changed = socket_select($read = NULL, $check_socket, $except = NULL, 0, 0);
 198 //        if($socket_changed > 0) {
 199 //
 200 //            // ABOVE CODE GOES HERE
 201 //
 202 //        }
 203 //        return false;
 204     }
 205
 206     function user_lazy_update($sessionid) {
 207         // TODO: this can and should be written as a single UPDATE query
 208         if(empty($this->sets_info[$sessionid])) {
 209             $this->trace('user_lazy_update() called for an invalid SID: '.$sessionid, E_USER_WARNING);
 210             return false;
 211         }
 212
 213         $now = time();
 214
 215         // We 'll be cheating a little, and NOT updating the record data as
 216         // often as we can, so that we save on DB queries (imagine MANY users)
 217         if($now - $this->sets_info[$sessionid]['lastinfocommit'] > $this->_freq_update_records) {
 218             // commit to permanent storage
 219             $this->sets_info[$sessionid]['lastinfocommit'] = $now;
 220             update_record('chat_users', $this->sets_info[$sessionid]['chatuser']);
 221         }
 222         return true;
 223     }
 224
 225     function get_user_window($sessionid) {
 226
 227         global $CFG;
 228
 229         static $str;
 230
 231         $info = &$this->sets_info[$sessionid];
 232         course_setup($info['course'], $info['user']);
 233
 234         $timenow = time();
 235
 236         if (empty($str)) {
 237             $str->idle  = get_string("idle", "chat");
 238             $str->beep  = get_string("beep", "chat");
 239             $str->day   = get_string("day");
 240             $str->days  = get_string("days");
 241             $str->hour  = get_string("hour");
 242             $str->hours = get_string("hours");
 243             $str->min   = get_string("min");
 244             $str->mins  = get_string("mins");
 245             $str->sec   = get_string("sec");
 246             $str->secs  = get_string("secs");
 247             $str->years = get_string('years');
 248         }
 249
 250         ob_start();
 251         echo '<html><head>';
 252         echo '<script text="text/javascript">';
 253         echo "//<![CDATA[\n";
 254
 255         echo 'function openpopup(url,name,options,fullscreen) {';
 256         echo 'fullurl = "'.$CFG->wwwroot.'" + url;';
 257         echo 'windowobj = window.open(fullurl,name,options);';
 258         echo 'if (fullscreen) {';
 259         echo '  windowobj.moveTo(0,0);';
 260         echo '  windowobj.resizeTo(screen.availWidth,screen.availHeight); ';
 261         echo '}';
 262         echo 'windowobj.focus();';
 263         echo 'return false;';
 264         echo "}\n//]]>\n";
 265         echo '</script></head><body style="font-face: serif;" bgcolor="#FFFFFF">';
 266
 267         echo '<table style="width: 100%;"><tbody>';
 268
 269         // Get the users from that chatroom
 270         $users = $this->chatrooms[$info['chatid']]['users'];
 271
 272         foreach ($users as $usersessionid => $userid) {
 273             // Fetch each user's sessionid and then the rest of his data from $this->sets_info
 274             $userinfo = $this->sets_info[$usersessionid];
 275
 276             $lastping = $timenow - $userinfo['chatuser']->lastmessageping;
 277             $popuppar = '\'/user/view.php?id='.$userinfo['user']->id.'&amp;course='.$userinfo['courseid'].'\',\'user'.$userinfo['chatuser']->id.'\',\'\'';
 278             echo '<tr><td width="35">';
 279             echo '<a target="_new" onclick="return openpopup('.$popuppar.');" href="'.$CFG->wwwroot.'/user/view.php?id='.$userinfo['chatuser']->id.'&amp;course='.$userinfo['courseid'].'">';
 280             print_user_picture($userinfo['user']->id, 0, $userinfo['user']->picture, false, false, false);
 281             echo "</a></td><td valign=\"center\">";
 282             echo "<p><font size=\"1\">";
 283             echo fullname($userinfo['user'])."<br />";
 284             echo "<font color=\"#888888\">$str->idle: ".format_time($lastping, $str)."</font> ";
 285             echo '<a target="empty" href="http://'.$CFG->chat_serverhost.':'.$CFG->chat_serverport.'/?win=beep&amp;beep='.$userinfo['user']->id.
 286                  '&chat_sid='.$sessionid.'">'.$str->beep."</a>\n";
 287             echo "</font></p>";
 288             echo "<td></tr>";
 289         }
 290
 291         echo '</tbody></table>';
 292
 293         // About 2K of HTML comments to force browsers to render the HTML
 294         // echo $GLOBALS['CHAT_DUMMY_DATA'];
 295
 296         echo "</body>\n</html>\n";
 297
 298         return ob_get_clean();
 299
 300     }
 301
 302     function new_ufo_id() {
 303         static $id = 0;
 304         if($id++ === 0x1000000) { // Cycling very very slowly to prevent overflow
 305             $id = 0;
 306         }
 307         return $id;
 308     }
 309
 310     function process_sidekicks($sessionid) {
 311         if(empty($this->conn_side[$sessionid])) {
 312             return true;
 313         }
 314         foreach($this->conn_side[$sessionid] as $sideid => $sidekick) {
 315             // TODO: is this late-dispatch working correctly?
 316             $this->dispatch_sidekick($sidekick['handle'], $sidekick['type'], $sessionid, $sidekick['customdata']);
 317             unset($this->conn_side[$sessionid][$sideid]);
 318         }
 319         return true;
 320     }
 321
 322     function dispatch_sidekick($handle, $type, $sessionid, $customdata) {
 323         global $CFG;
 324
 325         switch($type) {
 326             case CHAT_SIDEKICK_BEEP:
 327                 // Incoming beep
 328                 $msg = &New stdClass;
 329                 $msg->chatid    = $this->sets_info[$sessionid]['chatid'];
 330                 $msg->userid    = $this->sets_info[$sessionid]['userid'];
 331                 $msg->groupid   = $this->sets_info[$sessionid]['groupid'];
 332                 $msg->system    = 0;
 333                 $msg->message   = 'beep '.$customdata['beep'];
 334                 $msg->timestamp = time();
 335
 336                 // Commit to DB
 337                 insert_record('chat_messages', $msg, false);
 338
 339                 // OK, now push it out to all users
 340                 $this->message_broadcast($msg, $this->sets_info[$sessionid]['user']);
 341
 342                 // Update that user's lastmessageping
 343                 $this->sets_info[$sessionid]['chatuser']->lastping        = $msg->timestamp;
 344                 $this->sets_info[$sessionid]['chatuser']->lastmessageping = $msg->timestamp;
 345                 $this->user_lazy_update($sessionid);
 346
 347                 // We did our work, but before slamming the door on the poor browser
 348                 // show the courtesy of responding to the HTTP request. Otherwise, some
 349                 // browsers decide to get vengeance by flooding us with repeat requests.
 350
 351                 $header  = "HTTP/1.1 200 OK\n";
 352                 $header .= "Connection: close\n";
 353                 $header .= "Date: ".date('r')."\n";
 354                 $header .= "Server: Moodle\n";
 355                 $header .= "Content-Type: text/html\n";
 356                 $header .= "Last-Modified: ".gmdate("D, d M Y H:i:s")." GMT\n";
 357                 $header .= "Cache-Control: no-cache, must-revalidate\n";
 358                 $header .= "Expires: Wed, 4 Oct 1978 09:32:45 GMT\n";
 359                 $header .= "\n";
 360
 361                 // That's enough headers for one lousy dummy response
 362                 $this->write_data($handle, $header);
 363                 // All done
 364             break;
 365
 366             case CHAT_SIDEKICK_USERS:
 367                 // A request to paint a user window
 368
 369                 $content = $this->get_user_window($sessionid);
 370
 371                 $header  = "HTTP/1.1 200 OK\n";
 372                 $header .= "Connection: close\n";
 373                 $header .= "Date: ".date('r')."\n";
 374                 $header .= "Server: Moodle\n";
 375                 $header .= "Content-Type: text/html\n";
 376                 $header .= "Last-Modified: ".gmdate("D, d M Y H:i:s")." GMT\n";
 377                 $header .= "Cache-Control: no-cache, must-revalidate\n";
 378                 $header .= "Expires: Wed, 4 Oct 1978 09:32:45 GMT\n";
 379                 $header .= "Content-Length: ".strlen($content)."\n";
 380
 381                 // The refresh value is 2 seconds higher than the configuration variable because we are doing JS refreshes all the time.
 382                 // However, if the JS doesn't work for some reason, we still want to refresh once in a while.
 383                 $header .= "Refresh: ".(intval($CFG->chat_refresh_userlist) + 2)."; url=http://$CFG->chat_serverhost:$CFG->chat_serverport/?win=users&".
 384                            "chat_sid=".$sessionid."\n";
 385                 $header .= "\n";
 386
 387                 // That's enough headers for one lousy dummy response
 388                 $this->trace('writing users http response to handle '.$handle);
 389                 $this->write_data($handle, $header . $content);
 390
 391                 // Update that user's lastping
 392                 $this->sets_info[$sessionid]['chatuser']->lastping = time();
 393                 $this->user_lazy_update($sessionid);
 394
 395             break;
 396
 397             case CHAT_SIDEKICK_MESSAGE:
 398                 // Incoming message
 399
 400                 // Browser stupidity protection from duplicate messages:
 401                 $messageindex = intval($customdata['index']);
 402
 403                 if($this->sets_info[$sessionid]['lastmessageindex'] >= $messageindex) {
 404                     // We have already broadcasted that!
 405                     // $this->trace('discarding message with stale index');
 406                     break;
 407                 }
 408                 else {
 409                     // Update our info
 410                     $this->sets_info[$sessionid]['lastmessageindex'] = $messageindex;
 411                 }
 412
 413                 $msg = &New stdClass;
 414                 $msg->chatid    = $this->sets_info[$sessionid]['chatid'];
 415                 $msg->userid    = $this->sets_info[$sessionid]['userid'];
 416                 $msg->groupid   = $this->sets_info[$sessionid]['groupid'];
 417                 $msg->system    = 0;
 418                 $msg->message   = urldecode($customdata['message']); // have to undo the browser's encoding
 419                 $msg->timestamp = time();
 420
 421                 if(empty($msg->message)) {
 422                     // Someone just hit ENTER, send them on their way
 423                     break;
 424                 }
 425
 426                 // A slight hack to prevent malformed SQL inserts
 427                 $origmsg = $msg->message;
 428                 $msg->message = addslashes($msg->message);
 429
 430                 // Commit to DB
 431                 insert_record('chat_messages', $msg, false);
 432
 433                 // Undo the hack
 434                 $msg->message = $origmsg;
 435
 436                 // OK, now push it out to all users
 437                 $this->message_broadcast($msg, $this->sets_info[$sessionid]['user']);
 438
 439                 // Update that user's lastmessageping
 440                 $this->sets_info[$sessionid]['chatuser']->lastping        = $msg->timestamp;
 441                 $this->sets_info[$sessionid]['chatuser']->lastmessageping = $msg->timestamp;
 442                 $this->user_lazy_update($sessionid);
 443
 444                 // We did our work, but before slamming the door on the poor browser
 445                 // show the courtesy of responding to the HTTP request. Otherwise, some
 446                 // browsers decide to get vengeance by flooding us with repeat requests.
 447
 448                 $header  = "HTTP/1.1 200 OK\n";
 449                 $header .= "Connection: close\n";
 450                 $header .= "Date: ".date('r')."\n";
 451                 $header .= "Server: Moodle\n";
 452                 $header .= "Content-Type: text/html\n";
 453                 $header .= "Last-Modified: ".gmdate("D, d M Y H:i:s")." GMT\n";
 454                 $header .= "Cache-Control: no-cache, must-revalidate\n";
 455                 $header .= "Expires: Wed, 4 Oct 1978 09:32:45 GMT\n";
 456                 $header .= "\n";
 457
 458                 // That's enough headers for one lousy dummy response
 459                 $this->write_data($handle, $header);
 460
 461                 // All done
 462             break;
 463         }
 464
 465         socket_shutdown($handle);
 466         socket_close($handle);
 467     }
 468
 469     function promote_final($sessionid, $customdata) {
 470         if(isset($this->conn_sets[$sessionid])) {
 471             $this->trace('Set cannot be finalized: Session '.$sessionid.' is already active');
 472             return false;
 473         }
 474
 475         $chatuser = get_record('chat_users', 'sid', $sessionid);
 476         if($chatuser === false) {
 477             $this->dismiss_half($sessionid);
 478             return false;
 479         }
 480         $chat = get_record('chat', 'id', $chatuser->chatid);
 481         if($chat === false) {
 482             $this->dismiss_half($sessionid);
 483             return false;
 484         }
 485         $user = get_record('user', 'id', $chatuser->userid);
 486         if($user === false) {
 487             $this->dismiss_half($sessionid);
 488             return false;
 489         }
 490         $course = get_record('course', 'id', $chat->course); {
 491        if($course === false) {
 492             $this->dismiss_half($sessionid);
 493             return false;
 494             }
 495         }
 496
 497         global $CHAT_HTMLHEAD_JS, $CFG;
 498
 499         $this->conn_sets[$sessionid] = $this->conn_half[$sessionid];
 500
 501         // This whole thing needs to be purged of redundant info, and the
 502         // code base to follow suit. But AFTER development is done.
 503         $this->sets_info[$sessionid] = array(
 504             'lastinfocommit' => 0,
 505             'lastmessageindex' => 0,
 506             'course'    => $course,
 507             'courseid'  => $course->id,
 508             'chatuser'  => $chatuser,
 509             'chatid'    => $chat->id,
 510             'user'      => $user,
 511             'userid'    => $user->id,
 512             'groupid'   => $chatuser->groupid,
 513             'lang'      => $chatuser->lang,
 514             'quirks'    => $customdata['quirks']
 515         );
 516
 517         // If we know nothing about this chatroom, initialize it and add the user
 518         if(!isset($this->chatrooms[$chat->id]['users'])) {
 519             $this->chatrooms[$chat->id]['users'] = array($sessionid => $user->id);
 520         }
 521         else {
 522             // Otherwise just add the user
 523             $this->chatrooms[$chat->id]['users'][$sessionid] = $user->id;
 524         }
 525
 526         // $this->trace('QUIRKS value for this connection is '.$customdata['quirks']);
 527
 528         $this->dismiss_half($sessionid, false);
 529         $this->write_data($this->conn_sets[$sessionid][CHAT_CONNECTION_CHANNEL], $CHAT_HTMLHEAD_JS);
 530         $this->trace('Connection accepted: '.$this->conn_sets[$sessionid][CHAT_CONNECTION_CHANNEL].', SID: '.$sessionid.' UID: '.$chatuser->userid.' GID: '.$chatuser->groupid, E_USER_WARNING);
 531
 532         // Finally, broadcast the "entered the chat" message
 533
 534         $msg = &New stdClass;
 535         $msg->chatid = $chatuser->chatid;
 536         $msg->userid = $chatuser->userid;
 537         $msg->groupid = $chatuser->groupid;
 538         $msg->system = 1;
 539         $msg->message = 'enter';
 540         $msg->timestamp = time();
 541
 542         insert_record('chat_messages', $msg, false);
 543         $this->message_broadcast($msg, $this->sets_info[$sessionid]['user']);
 544
 545         return true;
 546     }
 547
 548     function promote_ufo($handle, $type, $sessionid, $customdata) {
 549         if(empty($this->conn_ufo)) {
 550             return false;
 551         }
 552         foreach($this->conn_ufo as $id => $ufo) {
 553             if($ufo->handle == $handle) {
 554                 // OK, got the id of the UFO, but what is it?
 555
 556                 if($type & CHAT_SIDEKICK) {
 557                     // Is the main connection ready?
 558                     if(isset($this->conn_sets[$sessionid])) {
 559                         // Yes, so dispatch this sidekick now and be done with it
 560                         //$this->trace('Dispatching sidekick immediately');
 561                         $this->dispatch_sidekick($handle, $type, $sessionid, $customdata);
 562                         $this->dismiss_ufo($handle, false);
 563                     }
 564                     else {
 565                         // No, so put it in the waiting list
 566                         $this->trace('sidekick waiting');
 567                         $this->conn_side[$sessionid][] = array('type' => $type, 'handle' => $handle, 'customdata' => $customdata);
 568                     }
 569                     return true;
 570                 }
 571
 572                 // If it's not a sidekick, at this point it can only be da man
 573
 574                 if($type & CHAT_CONNECTION) {
 575                     // This forces a new connection right now...
 576                     $this->trace('Incoming connection from '.$ufo->ip.':'.$ufo->port);
 577
 578                     // Do we have such a connection active?
 579                     if(isset($this->conn_sets[$sessionid])) {
 580                         // Yes, so regrettably we cannot promote you
 581                         $this->trace('Connection rejected: session '.$sessionid.' is already final');
 582                         $this->dismiss_ufo($handle, true, 'Your SID was rejected.');
 583                         return false;
 584                     }
 585
 586                     // Join this with what we may have already
 587                     $this->conn_half[$sessionid][$type] = $handle;
 588
 589                     // Do the bookkeeping
 590                     $this->promote_final($sessionid, $customdata);
 591
 592                     // It's not an UFO anymore
 593                     $this->dismiss_ufo($handle, false);
 594
 595                     // Dispatch waiting sidekicks
 596                     $this->process_sidekicks($sessionid);
 597
 598                     return true;
 599                 }
 600             }
 601         }
 602         return false;
 603     }
 604
 605     function dismiss_half($sessionid, $disconnect = true) {
 606         if(!isset($this->conn_half[$sessionid])) {
 607             return false;
 608         }
 609         if($disconnect) {
 610             foreach($this->conn_half[$sessionid] as $handle) {
 611                 @socket_shutdown($handle);
 612                 @socket_close($handle);
 613             }
 614         }
 615         unset($this->conn_half[$sessionid]);
 616         return true;
 617     }
 618
 619     function dismiss_set($sessionid) {
 620         if(!empty($this->conn_sets[$sessionid])) {
 621             foreach($this->conn_sets[$sessionid] as $handle) {
 622                 // Since we want to dismiss this, don't generate any errors if it's dead already
 623                 @socket_shutdown($handle);
 624                 @socket_close($handle);
 625             }
 626         }
 627         $chatroom = $this->sets_info[$sessionid]['chatid'];
 628         $userid   = $this->sets_info[$sessionid]['userid'];
 629         unset($this->conn_sets[$sessionid]);
 630         unset($this->sets_info[$sessionid]);
 631         unset($this->chatrooms[$chatroom]['users'][$sessionid]);
 632         $this->trace('Removed all traces of user with session '.$sessionid, E_USER_NOTICE);
 633         return true;
 634     }
 635
 636
 637     function dismiss_ufo($handle, $disconnect = true, $message = NULL) {
 638         if(empty($this->conn_ufo)) {
 639             return false;
 640         }
 641         foreach($this->conn_ufo as $id => $ufo) {
 642             if($ufo->handle == $handle) {
 643                 unset($this->conn_ufo[$id]);
 644                 if($disconnect) {
 645                     if(!empty($message)) {
 646                         $this->write_data($handle, $message."\n\n");
 647                     }
 648                     socket_shutdown($handle);
 649                     socket_close($handle);
 650                 }
 651                 return true;
 652             }
 653         }
 654         return false;
 655     }
 656
 657     function conn_accept() {
 658         $read_socket = array($this->listen_socket);
 659         $changed = socket_select($read_socket, $write = NULL, $except = NULL, 0, 0);
 660
 661         if(!$changed) {
 662             return false;
 663         }
 664         $handle = socket_accept($this->listen_socket);
 665         if(!$handle) {
 666             return false;
 667         }
 668
 669         $newconn = &New ChatConnection($handle);
 670         $id = $this->new_ufo_id();
 671         $this->conn_ufo[$id] = $newconn;
 672
 673         //$this->trace('UFO #'.$id.': connection from '.$newconn->ip.' on port '.$newconn->port.', '.$newconn->handle);
 674     }
 675
 676     function conn_activity_ufo (&$handles) {
 677         $monitor = array();
 678         if(!empty($this->conn_ufo)) {
 679             foreach($this->conn_ufo as $ufoid => $ufo) {
 680                 $monitor[$ufoid] = $ufo->handle;
 681             }
 682         }
 683
 684         if(empty($monitor)) {
 685             $handles = array();
 686             return 0;
 687         }
 688
 689         $retval = socket_select($monitor, $a = NULL, $b = NULL, NULL);
 690         $handles = $monitor;
 691
 692         return $retval;
 693     }
 694
 695     function message_broadcast($message, $sender) {
 696         if(empty($this->conn_sets)) {
 697             return true;
 698         }
 699
 700         $now = time();
 701
 702         // First of all, mark this chatroom as having had activity now
 703         $this->chatrooms[$message->chatid]['lastactivity'] = $now;
 704
 705         foreach($this->sets_info as $sessionid => $info) {
 706             // We need to get handles from users that are in the same chatroom, same group
 707             if($info['chatid'] == $message->chatid &&
 708               ($info['groupid'] == $message->groupid || $message->groupid == 0))
 709             {
 710
 711                 // Simply give them the message
 712                 course_setup($info['course'], $info['user']);
 713                 $output = chat_format_message_manually($message, $info['courseid'], $sender, $info['user']);
 714                 $this->trace('Delivering message "'.$output->text.'" to '.$this->conn_sets[$sessionid][CHAT_CONNECTION_CHANNEL]);
 715
 716                 if($output->beep) {
 717                     $this->write_data($this->conn_sets[$sessionid][CHAT_CONNECTION_CHANNEL], '<embed src="'.$this->_beepsoundsrc.'" autostart="true" hidden="true" />');
 718                 }
 719
 720                 if($info['quirks'] & QUIRK_CHUNK_UPDATE) {
 721                     $output->html .= $GLOBALS['CHAT_DUMMY_DATA'];
 722                     $output->html .= $GLOBALS['CHAT_DUMMY_DATA'];
 723                     $output->html .= $GLOBALS['CHAT_DUMMY_DATA'];
 724                 }
 725
 726                 if(!$this->write_data($this->conn_sets[$sessionid][CHAT_CONNECTION_CHANNEL], $output->html)) {
 727                     $this->disconnect_session($sessionid);
 728                 }
 729                 //$this->trace('Sent to UID '.$this->sets_info[$sessionid]['userid'].': '.$message->text_);
 730             }
 731         }
 732     }
 733
 734     function disconnect_session($sessionid) {
 735         $info = $this->sets_info[$sessionid];
 736
 737         delete_records('chat_users', 'sid', $sessionid);
 738         $msg = &New stdClass;
 739         $msg->chatid = $info['chatid'];
 740         $msg->userid = $info['userid'];
 741         $msg->groupid = $info['groupid'];
 742         $msg->system = 1;
 743         $msg->message = 'exit';
 744         $msg->timestamp = time();
 745
 746         $this->trace('User has disconnected, destroying uid '.$info['userid'].' with SID '.$sessionid, E_USER_WARNING);
 747         insert_record('chat_messages', $msg, false);
 748
 749         // *************************** IMPORTANT
 750         //
 751         // Kill him BEFORE broadcasting, otherwise we 'll get infinite recursion!
 752         //
 753         // **********************************************************************
 754         $latesender = $info['user'];
 755         $this->dismiss_set($sessionid);
 756         $this->message_broadcast($msg, $latesender);
 757     }
 758
 759     function fatal($message) {
 760         $message .= "\n";
 761         if($this->_logfile) {
 762             $this->trace($message, E_USER_ERROR);
 763         }
 764         echo "FATAL ERROR:: $message\n";
 765         die();
 766     }
 767
 768     function init_sockets() {
 769         global $CFG;
 770
 771         $this->trace('Setting up sockets');
 772
 773         if(false === ($this->listen_socket = socket_create(AF_INET, SOCK_STREAM, 0))) {
 774             // Failed to create socket
 775             $lasterr = socket_last_error();
 776             $this->fatal('socket_create() failed: '. socket_strerror($lasterr).' ['.$lasterr.']');
 777         }
 778
 779         //socket_close($DAEMON->listen_socket);
 780         //die();
 781
 782         if(!socket_bind($this->listen_socket, $CFG->chat_serverip, $CFG->chat_serverport)) {
 783             // Failed to bind socket
 784             $lasterr = socket_last_error();
 785             $this->fatal('socket_bind() failed: '. socket_strerror($lasterr).' ['.$lasterr.']');
 786         }
 787
 788         if(!socket_listen($this->listen_socket, $CFG->chat_servermax)) {
 789             // Failed to get socket to listen
 790             $lasterr = socket_last_error();
 791             $this->fatal('socket_listen() failed: '. socket_strerror($lasterr).' ['.$lasterr.']');
 792         }
 793
 794         // Socket has been initialized and is ready
 795         $this->trace('Socket opened on port '.$CFG->chat_serverport);
 796
 797         // [pj]: I really must have a good read on sockets. What exactly does this do?
 798         // http://www.unixguide.net/network/socketfaq/4.5.shtml is still not enlightening enough for me.
 799         socket_setopt($this->listen_socket, SOL_SOCKET, SO_REUSEADDR, 1);
 800         socket_set_nonblock($this->listen_socket);
 801     }
 802
 803     function cli_switch($switch, $param = NULL) {
 804         switch($switch) { //LOL
 805             case 'reset':
 806                 // Reset sockets
 807                 $this->_resetsocket = true;
 808                 return false;
 809             case 'start':
 810                 // Start the daemon
 811                 $this->_readytogo = true;
 812                 return false;
 813             break;
 814             case 'v':
 815                 // Verbose mode
 816                 $this->_trace_level = E_ALL;
 817                 return false;
 818             break;
 819             case 'l':
 820                 // Use logfile
 821                 if(!empty($param)) {
 822                     $this->_logfile_name = $param;
 823                 }
 824                 $this->_logfile = @fopen($this->_logfile_name, 'a+');
 825                 if($this->_logfile == false) {
 826                     $this->fatal('Failed to open '.$this->_logfile_name.' for writing');
 827                 }
 828                 return false;
 829             default:
 830                 // Unrecognized
 831                 $this->fatal('Unrecognized command line switch: '.$switch);
 832             break;
 833         }
 834         return false;
 835     }
 836
 837 }
 838
 839 $DAEMON = New ChatDaemon;
 840 set_error_handler(array($DAEMON, 'error_handler'));
 841
 842 /// Check the parameters //////////////////////////////////////////////////////
 843
 844 unset($argv[0]);
 845 $commandline = implode(' ', $argv);
 846 if(strpos($commandline, '-') === false) {
 847     if(!empty($commandline)) {
 848         // We cannot have received any meaningful parameters
 849         $DAEMON->fatal('Garbage in command line');
 850     }
 851 }
 852 else {
 853     // Parse command line
 854     $switches = preg_split('/(-{1,2}[a-zA-Z]+) */', $commandline, -1, PREG_SPLIT_NO_EMPTY | PREG_SPLIT_DELIM_CAPTURE);
 855
 856     // Taking advantage of the fact that $switches is indexed with incrementing numeric keys
 857     // We will be using that to pass additional information to those switches who need it
 858     $numswitches = count($switches);
 859
 860     // Fancy way to give a "hyphen" boolean flag to each "switch"
 861     $switches = array_map(create_function('$x', 'return array("str" => $x, "hyphen" => (substr($x, 0, 1) == "-"));'), $switches);
 862
 863     for($i = 0; $i < $numswitches; ++$i) {
 864
 865         $switch = $switches[$i]['str'];
 866         $params = ($i == $numswitches - 1 ? NULL :
 867                                             ($switches[$i + 1]['hyphen'] ? NULL : trim($switches[$i + 1]['str']))
 868                   );
 869
 870         if(substr($switch, 0, 2) == '--') {
 871             // Double-hyphen switch
 872             $DAEMON->cli_switch(strtolower(substr($switch, 2)), $params);
 873         }
 874         else if(substr($switch, 0, 1) == '-') {
 875             // Single-hyphen switch(es), may be more than one run together
 876             $switch = substr($switch, 1); // Get rid of the -
 877             $len = strlen($switch);
 878             for($j = 0; $j < $len; ++$j) {
 879                 $DAEMON->cli_switch(strtolower(substr($switch, $j, 1)), $params);
 880             }
 881         }
 882     }
 883 }
 884
 885 if(!$DAEMON->query_start()) {
 886     // For some reason we didn't start, so print out some info
 887     echo 'Starts the Moodle chat socket server on port '.$CFG->chat_serverport;
 888     echo "\n\n";
 889     echo "Usage: chatd.php [parameters]\n\n";
 890     echo "Parameters:\n";
 891     echo "  --start         Starts the daemon\n";
 892     echo "  -v              Verbose mode (prints trivial information messages)\n";
 893     echo "  -l [logfile]    Log all messages to logfile (if not specified, chatd.log)\n";
 894     echo "Example:\n";
 895     echo "  chatd.php --start -l\n\n";
 896     die();
 897 }
 898
 899 if (!function_exists('socket_setopt')) {
 900     echo "Error: Function socket_setopt() does not exist.\n";
 901     echo "Possibly PHP has not been compiled with --enable-sockets.\n\n";
 902     die();
 903 }
 904
 905 $DAEMON->init_sockets();
 906
 907 /*
 908 declare(ticks=1);
 909
 910 $pid = pcntl_fork();
 911 if ($pid == -1) {
 912      die("could not fork");
 913 } else if ($pid) {
 914      exit(); // we are the parent
 915 } else {
 916      // we are the child
 917 }
 918
 919 // detatch from the controlling terminal
 920 if (!posix_setsid()) {
 921    die("could not detach from terminal");
 922 }
 923
 924 // setup signal handlers
 925 pcntl_signal(SIGTERM, "sig_handler");
 926 pcntl_signal(SIGHUP, "sig_handler");
 927
 928 if($DAEMON->_pcntl_exists && false) {
 929     $DAEMON->trace('Unholy spirit possession: daemonizing');
 930     $DAEMON->pid = pcntl_fork();
 931     if($pid == -1) {
 932         $DAEMON->trace('Process fork failed, terminating');
 933         die();
 934     }
 935     else if($pid) {
 936         // We are the parent
 937         $DAEMON->trace('Successfully forked the daemon with PID '.$pid);
 938         die();
 939     }
 940     else {
 941         // We are the daemon! :P
 942     }
 943
 944     // FROM NOW ON, IT'S THE DAEMON THAT'S RUNNING!
 945
 946     // Detach from controlling terminal
 947     if(!posix_setsid()) {
 948         $DAEMON->trace('Could not detach daemon process from terminal!');
 949     }
 950 }
 951 else {
 952     // Cannot go demonic
 953     $DAEMON->trace('Unholy spirit possession failed: PHP is not compiled with --enable-pcntl');
 954 }
 955 */
 956
 957 $DAEMON->trace('Started Moodle chatd on port '.$CFG->chat_serverport.', listening socket '.$DAEMON->listen_socket, E_USER_WARNING);
 958
 959 /// Clear the decks of old stuff
 960 delete_records('chat_users', 'version', 'sockets');
 961
 962 while(true) {
 963     $active = array();
 964
 965     // First of all, let's see if any of our UFOs has identified itself
 966     if($DAEMON->conn_activity_ufo($active)) {
 967         foreach($active as $handle) {
 968             $read_socket = array($handle);
 969             $changed = socket_select($read_socket, $write = NULL, $except = NULL, 0, 0);
 970
 971             if($changed > 0) {
 972                 // Let's see what it has to say
 973
 974                 $data = socket_read($handle, 2048); // should be more than 512 to prevent empty pages and repeated messages!!
 975                 if(empty($data)) {
 976                     continue;
 977                 }
 978
 979                 if (strlen($data) == 2048) { // socket_read has more data, ignore all data
 980                     $DAEMON->trace('UFO with '.$handle.': Data too long; connection closed', E_USER_WARNING);
 981                     $DAEMON->dismiss_ufo($handle, true, 'Data too long; connection closed');
 982                     continue;
 983                 }
 984
 985                 if(!ereg('win=(chat|users|message|beep).*&chat_sid=([a-zA-Z0-9]*) HTTP', $data, $info)) {
 986                     // Malformed data
 987                     $DAEMON->trace('UFO with '.$handle.': Request with malformed data; connection closed', E_USER_WARNING);
 988                     $DAEMON->dismiss_ufo($handle, true, 'Request with malformed data; connection closed');
 989                     continue;
 990                 }
 991
 992                 $type      = $info[1];
 993                 $sessionid = $info[2];
 994
 995                 $customdata = array();
 996
 997                 switch($type) {
 998                     case 'chat':
 999                        $type = CHAT_CONNECTION_CHANNEL;
1000                         $customdata['quirks'] = 0;
1001                         if(strpos($data, 'Safari')) {
1002                             $DAEMON->trace('Safari identified...', E_USER_WARNING);
1003                             $customdata['quirks'] += QUIRK_CHUNK_UPDATE;
1004                         }
1005                     break;
1006                     case 'users':
1007                         $type = CHAT_SIDEKICK_USERS;
1008                     break;
1009                     case 'beep':
1010                         $type = CHAT_SIDEKICK_BEEP;
1011                         if(!ereg('beep=([^&]*)[& ]', $data, $info)) {
1012                             $DAEMON->trace('Beep sidekick did not contain a valid userid', E_USER_WARNING);
1013                             $DAEMON->dismiss_ufo($handle, true, 'Request with malformed data; connection closed');
1014                             continue;
1015                         }
1016                         else {
1017                             $customdata = array('beep' => intval($info[1]));
1018                         }
1019                     break;
1020                     case 'message':
1021                         $type = CHAT_SIDEKICK_MESSAGE;
1022                         if(!ereg('chat_message=([^&]*)[& ]chat_msgidnr=([^&]*)[& ]', $data, $info)) {
1023                             $DAEMON->trace('Message sidekick did not contain a valid message', E_USER_WARNING);
1024                             $DAEMON->dismiss_ufo($handle, true, 'Request with malformed data; connection closed');
1025                             continue;
1026                         }
1027                         else {
1028                             $customdata = array('message' => $info[1], 'index' => $info[2]);
1029                         }
1030                     break;
1031                     default:
1032                         $DAEMON->trace('UFO with '.$handle.': Request with unknown type; connection closed', E_USER_WARNING);
1033                         $DAEMON->dismiss_ufo($handle, true, 'Request with unknown type; connection closed');
1034                         continue;
1035                     break;
1036                 }
1037
1038                 // OK, now we know it's something good... promote it and pass it all the data it needs
1039                 $DAEMON->promote_ufo($handle, $type, $sessionid, $customdata);
1040                 continue;
1041             }
1042         }
1043     }
1044
1045     $now = time();
1046
1047     // Clean up chatrooms with no activity as required
1048     if($now - $DAEMON->_last_idle_poll >= $DAEMON->_freq_poll_idle_chat) {
1049         $DAEMON->poll_idle_chats($now);
1050     }
1051
1052     // Finally, accept new connections
1053     $DAEMON->conn_accept();
1054
1055     usleep($DAEMON->_time_rest_socket);
1056 }
1057
1058 @socket_shutdown($DAEMON->listen_socket, 0);
1059 die("\n\n-- terminated --\n");
1060
1061 ?>