libraries/Trackback.php

   1 <?php  if ( ! defined('BASEPATH')) exit('No direct script access allowed');
   2 /**
   3  * CodeIgniter
   4  *
   5  * An open source application development framework for PHP 4.3.2 or newer
   6  *
   7  * @package             CodeIgniter
   8  * @author              ExpressionEngine Dev Team
   9  * @copyright   Copyright (c) 2008, EllisLab, Inc.
  10  * @license             http://codeigniter.com/user_guide/license.html
  11  * @link                http://codeigniter.com
  12  * @since               Version 1.0
  13  * @filesource
  14  */
  15
  16 // ------------------------------------------------------------------------
  17
  18 /**
  19  * Trackback Class
  20  *
  21  * Trackback Sending/Receiving Class
  22  *
  23  * @package             CodeIgniter
  24  * @subpackage  Libraries
  25  * @category    Trackbacks
  26  * @author              ExpressionEngine Dev Team
  27  * @link                http://codeigniter.com/user_guide/libraries/trackback.html
  28  */
  29 class CI_Trackback {
  30
  31         var $time_format        = 'local';
  32         var $charset            = 'UTF-8';
  33         var $data                       = array('url' => '', 'title' => '', 'excerpt' => '', 'blog_name' => '', 'charset' => '');
  34         var $convert_ascii      = TRUE;
  35         var $response           = '';
  36         var $error_msg          = array();
  37
  38         /**
  39          * Constructor
  40          *
  41          * @access      public
  42          */
  43         function CI_Trackback()
  44         {
  45                 log_message('debug', "Trackback Class Initialized");
  46         }
  47
  48         // --------------------------------------------------------------------
  49
  50         /**
  51          * Send Trackback
  52          *
  53          * @access      public
  54          * @param       array
  55          * @return      bool
  56          */
  57         function send($tb_data)
  58         {
  59                 if ( ! is_array($tb_data))
  60                 {
  61                         $this->set_error('The send() method must be passed an array');
  62                         return FALSE;
  63                 }
  64
  65                 // Pre-process the Trackback Data
  66                 foreach (array('url', 'title', 'excerpt', 'blog_name', 'ping_url') as $item)
  67                 {
  68                         if ( ! isset($tb_data[$item]))
  69                         {
  70                                 $this->set_error('Required item missing: '.$item);
  71                                 return FALSE;
  72                         }
  73
  74                         switch ($item)
  75                         {
  76                                 case 'ping_url' : $$item = $this->extract_urls($tb_data[$item]);
  77                                         break;
  78                                 case 'excerpt'  : $$item = $this->limit_characters($this->convert_xml(strip_tags(stripslashes($tb_data[$item]))));
  79                                         break;
  80                                 case 'url'              : $$item = str_replace('&#45;', '-', $this->convert_xml(strip_tags(stripslashes($tb_data[$item]))));
  81                                         break;
  82                                 default                 : $$item = $this->convert_xml(strip_tags(stripslashes($tb_data[$item])));
  83                                         break;
  84                         }
  85
  86                         // Convert High ASCII Characters
  87                         if ($this->convert_ascii == TRUE)
  88                         {
  89                                 if ($item == 'excerpt')
  90                                 {
  91                                         $$item = $this->convert_ascii($$item);
  92                                 }
  93                                 elseif ($item == 'title')
  94                                 {
  95                                         $$item = $this->convert_ascii($$item);
  96                                 }
  97                                 elseif($item == 'blog_name')
  98                                 {
  99                                         $$item = $this->convert_ascii($$item);
 100                                 }
 101                         }
 102                 }
 103
 104                 // Build the Trackback data string
 105                 $charset = ( ! isset($tb_data['charset'])) ? $this->charset : $tb_data['charset'];
 106
 107                 $data = "url=".rawurlencode($url)."&title=".rawurlencode($title)."&blog_name=".rawurlencode($blog_name)."&excerpt=".rawurlencode($excerpt)."&charset=".rawurlencode($charset);
 108
 109                 // Send Trackback(s)
 110                 $return = TRUE;
 111                 if (count($ping_url) > 0)
 112                 {
 113                         foreach ($ping_url as $url)
 114                         {
 115                                 if ($this->process($url, $data) == FALSE)
 116                                 {
 117                                         $return = FALSE;
 118                                 }
 119                         }
 120                 }
 121
 122                 return $return;
 123         }
 124
 125         // --------------------------------------------------------------------
 126
 127         /**
 128          * Receive Trackback  Data
 129          *
 130          * This function simply validates the incoming TB data.
 131          * It returns false on failure and true on success.
 132          * If the data is valid it is set to the $this->data array
 133          * so that it can be inserted into a database.
 134          *
 135          * @access      public
 136          * @return      bool
 137          */
 138         function receive()
 139         {
 140                 foreach (array('url', 'title', 'blog_name', 'excerpt') as $val)
 141                 {
 142                         if ( ! isset($_POST[$val]) OR $_POST[$val] == '')
 143                         {
 144                                 $this->set_error('The following required POST variable is missing: '.$val);
 145                                 return FALSE;
 146                         }
 147
 148                         $this->data['charset'] = ( ! isset($_POST['charset'])) ? 'auto' : strtoupper(trim($_POST['charset']));
 149
 150                         if ($val != 'url' && function_exists('mb_convert_encoding'))
 151                         {
 152                                 $_POST[$val] = mb_convert_encoding($_POST[$val], $this->charset, $this->data['charset']);
 153                         }
 154
 155                         $_POST[$val] = ($val != 'url') ? $this->convert_xml(strip_tags($_POST[$val])) : strip_tags($_POST[$val]);
 156
 157                         if ($val == 'excerpt')
 158                         {
 159                                 $_POST['excerpt'] = $this->limit_characters($_POST['excerpt']);
 160                         }
 161
 162                         $this->data[$val] = $_POST[$val];
 163                 }
 164
 165                 return TRUE;
 166         }
 167
 168         // --------------------------------------------------------------------
 169
 170         /**
 171          * Send Trackback Error Message
 172          *
 173          * Allows custom errors to be set.  By default it
 174          * sends the "incomplete information" error, as that's
 175          * the most common one.
 176          *
 177          * @access      public
 178          * @param       string
 179          * @return      void
 180          */
 181         function send_error($message = 'Incomplete Information')
 182         {
 183                 echo "<?xml version=\"1.0\" encoding=\"utf-8\"?".">\n<response>\n<error>1</error>\n<message>".$message."</message>\n</response>";
 184                 exit;
 185         }
 186
 187         // --------------------------------------------------------------------
 188
 189         /**
 190          * Send Trackback Success Message
 191          *
 192          * This should be called when a trackback has been
 193          * successfully received and inserted.
 194          *
 195          * @access      public
 196          * @return      void
 197          */
 198         function send_success()
 199         {
 200                 echo "<?xml version=\"1.0\" encoding=\"utf-8\"?".">\n<response>\n<error>0</error>\n</response>";
 201                 exit;
 202         }
 203
 204         // --------------------------------------------------------------------
 205
 206         /**
 207          * Fetch a particular item
 208          *
 209          * @access      public
 210          * @param       string
 211          * @return      string
 212          */
 213         function data($item)
 214         {
 215                 return ( ! isset($this->data[$item])) ? '' : $this->data[$item];
 216         }
 217
 218         // --------------------------------------------------------------------
 219
 220         /**
 221          * Process Trackback
 222          *
 223          * Opens a socket connection and passes the data to
 224          * the server.  Returns true on success, false on failure
 225          *
 226          * @access      public
 227          * @param       string
 228          * @param       string
 229          * @return      bool
 230          */
 231         function process($url, $data)
 232         {
 233                 $target = parse_url($url);
 234
 235                 // Open the socket
 236                 if ( ! $fp = @fsockopen($target['host'], 80))
 237                 {
 238                         $this->set_error('Invalid Connection: '.$url);
 239                         return FALSE;
 240                 }
 241
 242                 // Build the path
 243                 $ppath = ( ! isset($target['path'])) ? $url : $target['path'];
 244
 245                 $path = (isset($target['query']) && $target['query'] != "") ? $ppath.'?'.$target['query'] : $ppath;
 246
 247                 // Add the Trackback ID to the data string
 248                 if ($id = $this->get_id($url))
 249                 {
 250                         $data = "tb_id=".$id."&".$data;
 251                 }
 252
 253                 // Transfer the data
 254                 fputs ($fp, "POST " . $path . " HTTP/1.0\r\n" );
 255                 fputs ($fp, "Host: " . $target['host'] . "\r\n" );
 256                 fputs ($fp, "Content-type: application/x-www-form-urlencoded\r\n" );
 257                 fputs ($fp, "Content-length: " . strlen($data) . "\r\n" );
 258                 fputs ($fp, "Connection: close\r\n\r\n" );
 259                 fputs ($fp, $data);
 260
 261                 // Was it successful?
 262                 $this->response = "";
 263
 264                 while( ! feof($fp))
 265                 {
 266                         $this->response .= fgets($fp, 128);
 267                 }
 268                 @fclose($fp);
 269
 270                 if ( ! eregi("<error>0</error>", $this->response))
 271                 {
 272                         $message = 'An unknown error was encountered';
 273
 274                         if (preg_match("/<message>(.*?)<\/message>/is", $this->response, $match))
 275                         {
 276                                 $message = trim($match['1']);
 277                         }
 278
 279                         $this->set_error($message);
 280                         return FALSE;
 281                 }
 282
 283                 return TRUE;
 284         }
 285
 286         // --------------------------------------------------------------------
 287
 288         /**
 289          * Extract Trackback URLs
 290          *
 291          * This function lets multiple trackbacks be sent.
 292          * It takes a string of URLs (separated by comma or
 293          * space) and puts each URL into an array
 294          *
 295          * @access      public
 296          * @param       string
 297          * @return      string
 298          */
 299         function extract_urls($urls)
 300         {
 301                 // Remove the pesky white space and replace with a comma.
 302                 $urls = preg_replace("/\s*(\S+)\s*/", "\\1,", $urls);
 303
 304                 // If they use commas get rid of the doubles.
 305                 $urls = str_replace(",,", ",", $urls);
 306
 307                 // Remove any comma that might be at the end
 308                 if (substr($urls, -1) == ",")
 309                 {
 310                         $urls = substr($urls, 0, -1);
 311                 }
 312
 313                 // Break into an array via commas
 314                 $urls = preg_split('/[,]/', $urls);
 315
 316                 // Removes duplicates
 317                 $urls = array_unique($urls);
 318
 319                 array_walk($urls, array($this, 'validate_url'));
 320
 321                 return $urls;
 322         }
 323
 324         // --------------------------------------------------------------------
 325
 326         /**
 327          * Validate URL
 328          *
 329          * Simply adds "http://" if missing
 330          *
 331          * @access      public
 332          * @param       string
 333          * @return      string
 334          */
 335         function validate_url($url)
 336         {
 337                 $url = trim($url);
 338
 339                 if (substr($url, 0, 4) != "http")
 340                 {
 341                         $url = "http://".$url;
 342                 }
 343         }
 344
 345         // --------------------------------------------------------------------
 346
 347         /**
 348          * Find the Trackback URL's ID
 349          *
 350          * @access      public
 351          * @param       string
 352          * @return      string
 353          */
 354         function get_id($url)
 355         {
 356                 $tb_id = "";
 357
 358                 if (strstr($url, '?'))
 359                 {
 360                         $tb_array = explode('/', $url);
 361                         $tb_end   = $tb_array[count($tb_array)-1];
 362
 363                         if ( ! is_numeric($tb_end))
 364                         {
 365                                 $tb_end  = $tb_array[count($tb_array)-2];
 366                         }
 367
 368                         $tb_array = explode('=', $tb_end);
 369                         $tb_id  = $tb_array[count($tb_array)-1];
 370                 }
 371                 else
 372                 {
 373                         if (ereg("/$", $url))
 374                         {
 375                                 $url = substr($url, 0, -1);
 376                         }
 377
 378                         $tb_array = explode('/', $url);
 379                         $tb_id  = $tb_array[count($tb_array)-1];
 380
 381                         if ( ! is_numeric($tb_id))
 382                         {
 383                                 $tb_id  = $tb_array[count($tb_array)-2];
 384                         }
 385                 }
 386
 387                 if ( ! preg_match ("/^([0-9]+)$/", $tb_id))
 388                 {
 389                         return false;
 390                 }
 391                 else
 392                 {
 393                         return $tb_id;
 394                 }
 395         }
 396
 397         // --------------------------------------------------------------------
 398
 399         /**
 400          * Convert Reserved XML characters to Entities
 401          *
 402          * @access      public
 403          * @param       string
 404          * @return      string
 405          */
 406         function convert_xml($str)
 407         {
 408                 $temp = '__TEMP_AMPERSANDS__';
 409
 410                 $str = preg_replace("/&#(\d+);/", "$temp\\1;", $str);
 411                 $str = preg_replace("/&(\w+);/",  "$temp\\1;", $str);
 412
 413                 $str = str_replace(array("&","<",">","\"", "'", "-"),
 414                                                    array("&amp;", "&lt;", "&gt;", "&quot;", "&#39;", "&#45;"),
 415                                                    $str);
 416
 417                 $str = preg_replace("/$temp(\d+);/","&#\\1;",$str);
 418                 $str = preg_replace("/$temp(\w+);/","&\\1;", $str);
 419
 420                 return $str;
 421         }
 422
 423         // --------------------------------------------------------------------
 424
 425         /**
 426          * Character limiter
 427          *
 428          * Limits the string based on the character count. Will preserve complete words.
 429          *
 430          * @access      public
 431          * @param       string
 432          * @param       integer
 433          * @param       string
 434          * @return      string
 435          */
 436         function limit_characters($str, $n = 500, $end_char = '&#8230;')
 437         {
 438                 if (strlen($str) < $n)
 439                 {
 440                         return $str;
 441                 }
 442
 443                 $str = preg_replace("/\s+/", ' ', str_replace(array("\r\n", "\r", "\n"), ' ', $str));
 444
 445                 if (strlen($str) <= $n)
 446                 {
 447                         return $str;
 448                 }
 449
 450                 $out = "";
 451                 foreach (explode(' ', trim($str)) as $val)
 452                 {
 453                         $out .= $val.' ';
 454                         if (strlen($out) >= $n)
 455                         {
 456                                 return trim($out).$end_char;
 457                         }
 458                 }
 459         }
 460
 461         // --------------------------------------------------------------------
 462
 463         /**
 464          * High ASCII to Entities
 465          *
 466          * Converts Hight ascii text and MS Word special chars
 467          * to character entities
 468          *
 469          * @access      public
 470          * @param       string
 471          * @return      string
 472          */
 473         function convert_ascii($str)
 474         {
 475            $count       = 1;
 476            $out = '';
 477            $temp        = array();
 478
 479            for ($i = 0, $s = strlen($str); $i < $s; $i++)
 480            {
 481                    $ordinal = ord($str[$i]);
 482
 483                    if ($ordinal < 128)
 484                    {
 485                            $out .= $str[$i];
 486                    }
 487                    else
 488                    {
 489                            if (count($temp) == 0)
 490                            {
 491                                    $count = ($ordinal < 224) ? 2 : 3;
 492                            }
 493
 494                            $temp[] = $ordinal;
 495
 496                            if (count($temp) == $count)
 497                            {
 498                                    $number = ($count == 3) ? (($temp['0'] % 16) * 4096) + (($temp['1'] % 64) * 64) + ($temp['2'] % 64) : (($temp['0'] % 32) * 64) + ($temp['1'] % 64);
 499
 500                                    $out .= '&#'.$number.';';
 501                                    $count = 1;
 502                                    $temp = array();
 503                            }
 504                    }
 505            }
 506
 507            return $out;
 508         }
 509
 510         // --------------------------------------------------------------------
 511
 512         /**
 513          * Set error message
 514          *
 515          * @access      public
 516          * @param       string
 517          * @return      void
 518          */
 519         function set_error($msg)
 520         {
 521                 log_message('error', $msg);
 522                 $this->error_msg[] = $msg;
 523         }
 524
 525         // --------------------------------------------------------------------
 526
 527         /**
 528          * Show error messages
 529          *
 530          * @access      public
 531          * @param       string
 532          * @param       string
 533          * @return      string
 534          */
 535         function display_errors($open = '<p>', $close = '</p>')
 536         {
 537                 $str = '';
 538                 foreach ($this->error_msg as $val)
 539                 {
 540                         $str .= $open.$val.$close;
 541                 }
 542
 543                 return $str;
 544         }
 545
 546 }
 547 // END Trackback Class
 548
 549 /* End of file Trackback.php */
 550 /* Location: ./system/libraries/Trackback.php */