includes/parser/Preprocessor_DOM.php

   1 <?php
   2 /**
   3  * Preprocessor using PHP's dom extension
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @ingroup Parser
  22  */
  23
  24 /**
  25  * @ingroup Parser
  26  */
  27 class Preprocessor_DOM implements Preprocessor {
  28
  29         /**
  30          * @var Parser
  31          */
  32         var $parser;
  33
  34         var $memoryLimit;
  35
  36         const CACHE_VERSION = 1;
  37
  38         function __construct( $parser ) {
  39                 $this->parser = $parser;
  40                 $mem = ini_get( 'memory_limit' );
  41                 $this->memoryLimit = false;
  42                 if ( strval( $mem ) !== '' && $mem != -1 ) {
  43                         if ( preg_match( '/^\d+$/', $mem ) ) {
  44                                 $this->memoryLimit = $mem;
  45                         } elseif ( preg_match( '/^(\d+)M$/i', $mem, $m ) ) {
  46                                 $this->memoryLimit = $m[1] * 1048576;
  47                         }
  48                 }
  49         }
  50
  51         /**
  52          * @return PPFrame_DOM
  53          */
  54         function newFrame() {
  55                 return new PPFrame_DOM( $this );
  56         }
  57
  58         /**
  59          * @param $args array
  60          * @return PPCustomFrame_DOM
  61          */
  62         function newCustomFrame( $args ) {
  63                 return new PPCustomFrame_DOM( $this, $args );
  64         }
  65
  66         /**
  67          * @param $values
  68          * @return PPNode_DOM
  69          */
  70         function newPartNodeArray( $values ) {
  71                 //NOTE: DOM manipulation is slower than building & parsing XML! (or so Tim sais)
  72                 $xml = "<list>";
  73
  74                 foreach ( $values as $k => $val ) {
  75                         if ( is_int( $k ) ) {
  76                                 $xml .= "<part><name index=\"$k\"/><value>" . htmlspecialchars( $val ) . "</value></part>";
  77                         } else {
  78                                 $xml .= "<part><name>" . htmlspecialchars( $k ) . "</name>=<value>" . htmlspecialchars( $val ) . "</value></part>";
  79                         }
  80                 }
  81
  82                 $xml .= "</list>";
  83
  84                 $dom = new DOMDocument();
  85                 $dom->loadXML( $xml );
  86                 $root = $dom->documentElement;
  87
  88                 $node = new PPNode_DOM( $root->childNodes );
  89                 return $node;
  90         }
  91
  92         /**
  93          * @throws MWException
  94          * @return bool
  95          */
  96         function memCheck() {
  97                 if ( $this->memoryLimit === false ) {
  98                         return true;
  99                 }
 100                 $usage = memory_get_usage();
 101                 if ( $usage > $this->memoryLimit * 0.9 ) {
 102                         $limit = intval( $this->memoryLimit * 0.9 / 1048576 + 0.5 );
 103                         throw new MWException( "Preprocessor hit 90% memory limit ($limit MB)" );
 104                 }
 105                 return $usage <= $this->memoryLimit * 0.8;
 106         }
 107
 108         /**
 109          * Preprocess some wikitext and return the document tree.
 110          * This is the ghost of Parser::replace_variables().
 111          *
 112          * @param string $text the text to parse
 113          * @param $flags Integer: bitwise combination of:
 114          *          Parser::PTD_FOR_INCLUSION    Handle "<noinclude>" and "<includeonly>" as if the text is being
 115          *                                     included. Default is to assume a direct page view.
 116          *
 117          * The generated DOM tree must depend only on the input text and the flags.
 118          * The DOM tree must be the same in OT_HTML and OT_WIKI mode, to avoid a regression of bug 4899.
 119          *
 120          * Any flag added to the $flags parameter here, or any other parameter liable to cause a
 121          * change in the DOM tree for a given text, must be passed through the section identifier
 122          * in the section edit link and thus back to extractSections().
 123          *
 124          * The output of this function is currently only cached in process memory, but a persistent
 125          * cache may be implemented at a later date which takes further advantage of these strict
 126          * dependency requirements.
 127          *
 128          * @throws MWException
 129          * @return PPNode_DOM
 130          */
 131         function preprocessToObj( $text, $flags = 0 ) {
 132                 wfProfileIn( __METHOD__ );
 133                 global $wgMemc, $wgPreprocessorCacheThreshold;
 134
 135                 $xml = false;
 136                 $cacheable = ( $wgPreprocessorCacheThreshold !== false
 137                         && strlen( $text ) > $wgPreprocessorCacheThreshold );
 138                 if ( $cacheable ) {
 139                         wfProfileIn( __METHOD__ . '-cacheable' );
 140
 141                         $cacheKey = wfMemcKey( 'preprocess-xml', md5( $text ), $flags );
 142                         $cacheValue = $wgMemc->get( $cacheKey );
 143                         if ( $cacheValue ) {
 144                                 $version = substr( $cacheValue, 0, 8 );
 145                                 if ( intval( $version ) == self::CACHE_VERSION ) {
 146                                         $xml = substr( $cacheValue, 8 );
 147                                         // From the cache
 148                                         wfDebugLog( "Preprocessor", "Loaded preprocessor XML from memcached (key $cacheKey)" );
 149                                 }
 150                         }
 151                 }
 152                 if ( $xml === false ) {
 153                         if ( $cacheable ) {
 154                                 wfProfileIn( __METHOD__ . '-cache-miss' );
 155                                 $xml = $this->preprocessToXml( $text, $flags );
 156                                 $cacheValue = sprintf( "%08d", self::CACHE_VERSION ) . $xml;
 157                                 $wgMemc->set( $cacheKey, $cacheValue, 86400 );
 158                                 wfProfileOut( __METHOD__ . '-cache-miss' );
 159                                 wfDebugLog( "Preprocessor", "Saved preprocessor XML to memcached (key $cacheKey)" );
 160                         } else {
 161                                 $xml = $this->preprocessToXml( $text, $flags );
 162                         }
 163
 164                 }
 165
 166                 // Fail if the number of elements exceeds acceptable limits
 167                 // Do not attempt to generate the DOM
 168                 $this->parser->mGeneratedPPNodeCount += substr_count( $xml, '<' );
 169                 $max = $this->parser->mOptions->getMaxGeneratedPPNodeCount();
 170                 if ( $this->parser->mGeneratedPPNodeCount > $max ) {
 171                         if ( $cacheable ) {
 172                                 wfProfileOut( __METHOD__ . '-cacheable' );
 173                         }
 174                         wfProfileOut( __METHOD__ );
 175                         throw new MWException( __METHOD__ . ': generated node count limit exceeded' );
 176                 }
 177
 178                 wfProfileIn( __METHOD__ . '-loadXML' );
 179                 $dom = new DOMDocument;
 180                 wfSuppressWarnings();
 181                 $result = $dom->loadXML( $xml );
 182                 wfRestoreWarnings();
 183                 if ( !$result ) {
 184                         // Try running the XML through UtfNormal to get rid of invalid characters
 185                         $xml = UtfNormal::cleanUp( $xml );
 186                         // 1 << 19 == XML_PARSE_HUGE, needed so newer versions of libxml2 don't barf when the XML is >256 levels deep
 187                         $result = $dom->loadXML( $xml, 1 << 19 );
 188                         if ( !$result ) {
 189                                 wfProfileOut( __METHOD__ . '-loadXML' );
 190                                 if ( $cacheable ) {
 191                                         wfProfileOut( __METHOD__ . '-cacheable' );
 192                                 }
 193                                 wfProfileOut( __METHOD__ );
 194                                 throw new MWException( __METHOD__ . ' generated invalid XML' );
 195                         }
 196                 }
 197                 $obj = new PPNode_DOM( $dom->documentElement );
 198                 wfProfileOut( __METHOD__ . '-loadXML' );
 199                 if ( $cacheable ) {
 200                         wfProfileOut( __METHOD__ . '-cacheable' );
 201                 }
 202                 wfProfileOut( __METHOD__ );
 203                 return $obj;
 204         }
 205
 206         /**
 207          * @param $text string
 208          * @param $flags int
 209          * @return string
 210          */
 211         function preprocessToXml( $text, $flags = 0 ) {
 212                 wfProfileIn( __METHOD__ );
 213                 $rules = array(
 214                         '{' => array(
 215                                 'end' => '}',
 216                                 'names' => array(
 217                                         2 => 'template',
 218                                         3 => 'tplarg',
 219                                 ),
 220                                 'min' => 2,
 221                                 'max' => 3,
 222                         ),
 223                         '[' => array(
 224                                 'end' => ']',
 225                                 'names' => array( 2 => null ),
 226                                 'min' => 2,
 227                                 'max' => 2,
 228                         )
 229                 );
 230
 231                 $forInclusion = $flags & Parser::PTD_FOR_INCLUSION;
 232
 233                 $xmlishElements = $this->parser->getStripList();
 234                 $enableOnlyinclude = false;
 235                 if ( $forInclusion ) {
 236                         $ignoredTags = array( 'includeonly', '/includeonly' );
 237                         $ignoredElements = array( 'noinclude' );
 238                         $xmlishElements[] = 'noinclude';
 239                         if ( strpos( $text, '<onlyinclude>' ) !== false && strpos( $text, '</onlyinclude>' ) !== false ) {
 240                                 $enableOnlyinclude = true;
 241                         }
 242                 } else {
 243                         $ignoredTags = array( 'noinclude', '/noinclude', 'onlyinclude', '/onlyinclude' );
 244                         $ignoredElements = array( 'includeonly' );
 245                         $xmlishElements[] = 'includeonly';
 246                 }
 247                 $xmlishRegex = implode( '|', array_merge( $xmlishElements, $ignoredTags ) );
 248
 249                 // Use "A" modifier (anchored) instead of "^", because ^ doesn't work with an offset
 250                 $elementsRegex = "~($xmlishRegex)(?:\s|\/>|>)|(!--)~iA";
 251
 252                 $stack = new PPDStack;
 253
 254                 $searchBase = "[{<\n"; #}
 255                 $revText = strrev( $text ); // For fast reverse searches
 256                 $lengthText = strlen( $text );
 257
 258                 $i = 0;                     # Input pointer, starts out pointing to a pseudo-newline before the start
 259                 $accum =& $stack->getAccum();   # Current accumulator
 260                 $accum = '<root>';
 261                 $findEquals = false;            # True to find equals signs in arguments
 262                 $findPipe = false;              # True to take notice of pipe characters
 263                 $headingIndex = 1;
 264                 $inHeading = false;        # True if $i is inside a possible heading
 265                 $noMoreGT = false;         # True if there are no more greater-than (>) signs right of $i
 266                 $findOnlyinclude = $enableOnlyinclude; # True to ignore all input up to the next <onlyinclude>
 267                 $fakeLineStart = true;     # Do a line-start run without outputting an LF character
 268
 269                 while ( true ) {
 270                         //$this->memCheck();
 271
 272                         if ( $findOnlyinclude ) {
 273                                 // Ignore all input up to the next <onlyinclude>
 274                                 $startPos = strpos( $text, '<onlyinclude>', $i );
 275                                 if ( $startPos === false ) {
 276                                         // Ignored section runs to the end
 277                                         $accum .= '<ignore>' . htmlspecialchars( substr( $text, $i ) ) . '</ignore>';
 278                                         break;
 279                                 }
 280                                 $tagEndPos = $startPos + strlen( '<onlyinclude>' ); // past-the-end
 281                                 $accum .= '<ignore>' . htmlspecialchars( substr( $text, $i, $tagEndPos - $i ) ) . '</ignore>';
 282                                 $i = $tagEndPos;
 283                                 $findOnlyinclude = false;
 284                         }
 285
 286                         if ( $fakeLineStart ) {
 287                                 $found = 'line-start';
 288                                 $curChar = '';
 289                         } else {
 290                                 # Find next opening brace, closing brace or pipe
 291                                 $search = $searchBase;
 292                                 if ( $stack->top === false ) {
 293                                         $currentClosing = '';
 294                                 } else {
 295                                         $currentClosing = $stack->top->close;
 296                                         $search .= $currentClosing;
 297                                 }
 298                                 if ( $findPipe ) {
 299                                         $search .= '|';
 300                                 }
 301                                 if ( $findEquals ) {
 302                                         // First equals will be for the template
 303                                         $search .= '=';
 304                                 }
 305                                 $rule = null;
 306                                 # Output literal section, advance input counter
 307                                 $literalLength = strcspn( $text, $search, $i );
 308                                 if ( $literalLength > 0 ) {
 309                                         $accum .= htmlspecialchars( substr( $text, $i, $literalLength ) );
 310                                         $i += $literalLength;
 311                                 }
 312                                 if ( $i >= $lengthText ) {
 313                                         if ( $currentClosing == "\n" ) {
 314                                                 // Do a past-the-end run to finish off the heading
 315                                                 $curChar = '';
 316                                                 $found = 'line-end';
 317                                         } else {
 318                                                 # All done
 319                                                 break;
 320                                         }
 321                                 } else {
 322                                         $curChar = $text[$i];
 323                                         if ( $curChar == '|' ) {
 324                                                 $found = 'pipe';
 325                                         } elseif ( $curChar == '=' ) {
 326                                                 $found = 'equals';
 327                                         } elseif ( $curChar == '<' ) {
 328                                                 $found = 'angle';
 329                                         } elseif ( $curChar == "\n" ) {
 330                                                 if ( $inHeading ) {
 331                                                         $found = 'line-end';
 332                                                 } else {
 333                                                         $found = 'line-start';
 334                                                 }
 335                                         } elseif ( $curChar == $currentClosing ) {
 336                                                 $found = 'close';
 337                                         } elseif ( isset( $rules[$curChar] ) ) {
 338                                                 $found = 'open';
 339                                                 $rule = $rules[$curChar];
 340                                         } else {
 341                                                 # Some versions of PHP have a strcspn which stops on null characters
 342                                                 # Ignore and continue
 343                                                 ++$i;
 344                                                 continue;
 345                                         }
 346                                 }
 347                         }
 348
 349                         if ( $found == 'angle' ) {
 350                                 $matches = false;
 351                                 // Handle </onlyinclude>
 352                                 if ( $enableOnlyinclude && substr( $text, $i, strlen( '</onlyinclude>' ) ) == '</onlyinclude>' ) {
 353                                         $findOnlyinclude = true;
 354                                         continue;
 355                                 }
 356
 357                                 // Determine element name
 358                                 if ( !preg_match( $elementsRegex, $text, $matches, 0, $i + 1 ) ) {
 359                                         // Element name missing or not listed
 360                                         $accum .= '&lt;';
 361                                         ++$i;
 362                                         continue;
 363                                 }
 364                                 // Handle comments
 365                                 if ( isset( $matches[2] ) && $matches[2] == '!--' ) {
 366                                         // To avoid leaving blank lines, when a comment is both preceded
 367                                         // and followed by a newline (ignoring spaces), trim leading and
 368                                         // trailing spaces and one of the newlines.
 369
 370                                         // Find the end
 371                                         $endPos = strpos( $text, '-->', $i + 4 );
 372                                         if ( $endPos === false ) {
 373                                                 // Unclosed comment in input, runs to end
 374                                                 $inner = substr( $text, $i );
 375                                                 $accum .= '<comment>' . htmlspecialchars( $inner ) . '</comment>';
 376                                                 $i = $lengthText;
 377                                         } else {
 378                                                 // Search backwards for leading whitespace
 379                                                 $wsStart = $i ? ( $i - strspn( $revText, ' ', $lengthText - $i ) ) : 0;
 380                                                 // Search forwards for trailing whitespace
 381                                                 // $wsEnd will be the position of the last space (or the '>' if there's none)
 382                                                 $wsEnd = $endPos + 2 + strspn( $text, ' ', $endPos + 3 );
 383                                                 // Eat the line if possible
 384                                                 // TODO: This could theoretically be done if $wsStart == 0, i.e. for comments at
 385                                                 // the overall start. That's not how Sanitizer::removeHTMLcomments() did it, but
 386                                                 // it's a possible beneficial b/c break.
 387                                                 if ( $wsStart > 0 && substr( $text, $wsStart - 1, 1 ) == "\n"
 388                                                         && substr( $text, $wsEnd + 1, 1 ) == "\n" )
 389                                                 {
 390                                                         $startPos = $wsStart;
 391                                                         $endPos = $wsEnd + 1;
 392                                                         // Remove leading whitespace from the end of the accumulator
 393                                                         // Sanity check first though
 394                                                         $wsLength = $i - $wsStart;
 395                                                         if ( $wsLength > 0 && substr( $accum, -$wsLength ) === str_repeat( ' ', $wsLength ) ) {
 396                                                                 $accum = substr( $accum, 0, -$wsLength );
 397                                                         }
 398                                                         // Do a line-start run next time to look for headings after the comment
 399                                                         $fakeLineStart = true;
 400                                                 } else {
 401                                                         // No line to eat, just take the comment itself
 402                                                         $startPos = $i;
 403                                                         $endPos += 2;
 404                                                 }
 405
 406                                                 if ( $stack->top ) {
 407                                                         $part = $stack->top->getCurrentPart();
 408                                                         if ( !( isset( $part->commentEnd ) && $part->commentEnd == $wsStart - 1 ) ) {
 409                                                                 $part->visualEnd = $wsStart;
 410                                                         }
 411                                                         // Else comments abutting, no change in visual end
 412                                                         $part->commentEnd = $endPos;
 413                                                 }
 414                                                 $i = $endPos + 1;
 415                                                 $inner = substr( $text, $startPos, $endPos - $startPos + 1 );
 416                                                 $accum .= '<comment>' . htmlspecialchars( $inner ) . '</comment>';
 417                                         }
 418                                         continue;
 419                                 }
 420                                 $name = $matches[1];
 421                                 $lowerName = strtolower( $name );
 422                                 $attrStart = $i + strlen( $name ) + 1;
 423
 424                                 // Find end of tag
 425                                 $tagEndPos = $noMoreGT ? false : strpos( $text, '>', $attrStart );
 426                                 if ( $tagEndPos === false ) {
 427                                         // Infinite backtrack
 428                                         // Disable tag search to prevent worst-case O(N^2) performance
 429                                         $noMoreGT = true;
 430                                         $accum .= '&lt;';
 431                                         ++$i;
 432                                         continue;
 433                                 }
 434
 435                                 // Handle ignored tags
 436                                 if ( in_array( $lowerName, $ignoredTags ) ) {
 437                                         $accum .= '<ignore>' . htmlspecialchars( substr( $text, $i, $tagEndPos - $i + 1 ) ) . '</ignore>';
 438                                         $i = $tagEndPos + 1;
 439                                         continue;
 440                                 }
 441
 442                                 $tagStartPos = $i;
 443                                 if ( $text[$tagEndPos - 1] == '/' ) {
 444                                         $attrEnd = $tagEndPos - 1;
 445                                         $inner = null;
 446                                         $i = $tagEndPos + 1;
 447                                         $close = '';
 448                                 } else {
 449                                         $attrEnd = $tagEndPos;
 450                                         // Find closing tag
 451                                         if ( preg_match( "/<\/" . preg_quote( $name, '/' ) . "\s*>/i",
 452                                                         $text, $matches, PREG_OFFSET_CAPTURE, $tagEndPos + 1 ) )
 453                                         {
 454                                                 $inner = substr( $text, $tagEndPos + 1, $matches[0][1] - $tagEndPos - 1 );
 455                                                 $i = $matches[0][1] + strlen( $matches[0][0] );
 456                                                 $close = '<close>' . htmlspecialchars( $matches[0][0] ) . '</close>';
 457                                         } else {
 458                                                 // No end tag -- let it run out to the end of the text.
 459                                                 $inner = substr( $text, $tagEndPos + 1 );
 460                                                 $i = $lengthText;
 461                                                 $close = '';
 462                                         }
 463                                 }
 464                                 // <includeonly> and <noinclude> just become <ignore> tags
 465                                 if ( in_array( $lowerName, $ignoredElements ) ) {
 466                                         $accum .= '<ignore>' . htmlspecialchars( substr( $text, $tagStartPos, $i - $tagStartPos ) )
 467                                                 . '</ignore>';
 468                                         continue;
 469                                 }
 470
 471                                 $accum .= '<ext>';
 472                                 if ( $attrEnd <= $attrStart ) {
 473                                         $attr = '';
 474                                 } else {
 475                                         $attr = substr( $text, $attrStart, $attrEnd - $attrStart );
 476                                 }
 477                                 $accum .= '<name>' . htmlspecialchars( $name ) . '</name>' .
 478                                         // Note that the attr element contains the whitespace between name and attribute,
 479                                         // this is necessary for precise reconstruction during pre-save transform.
 480                                         '<attr>' . htmlspecialchars( $attr ) . '</attr>';
 481                                 if ( $inner !== null ) {
 482                                         $accum .= '<inner>' . htmlspecialchars( $inner ) . '</inner>';
 483                                 }
 484                                 $accum .= $close . '</ext>';
 485                         } elseif ( $found == 'line-start' ) {
 486                                 // Is this the start of a heading?
 487                                 // Line break belongs before the heading element in any case
 488                                 if ( $fakeLineStart ) {
 489                                         $fakeLineStart = false;
 490                                 } else {
 491                                         $accum .= $curChar;
 492                                         $i++;
 493                                 }
 494
 495                                 $count = strspn( $text, '=', $i, 6 );
 496                                 if ( $count == 1 && $findEquals ) {
 497                                         // DWIM: This looks kind of like a name/value separator
 498                                         // Let's let the equals handler have it and break the potential heading
 499                                         // This is heuristic, but AFAICT the methods for completely correct disambiguation are very complex.
 500                                 } elseif ( $count > 0 ) {
 501                                         $piece = array(
 502                                                 'open' => "\n",
 503                                                 'close' => "\n",
 504                                                 'parts' => array( new PPDPart( str_repeat( '=', $count ) ) ),
 505                                                 'startPos' => $i,
 506                                                 'count' => $count );
 507                                         $stack->push( $piece );
 508                                         $accum =& $stack->getAccum();
 509                                         $flags = $stack->getFlags();
 510                                         extract( $flags );
 511                                         $i += $count;
 512                                 }
 513                         } elseif ( $found == 'line-end' ) {
 514                                 $piece = $stack->top;
 515                                 // A heading must be open, otherwise \n wouldn't have been in the search list
 516                                 assert( '$piece->open == "\n"' );
 517                                 $part = $piece->getCurrentPart();
 518                                 // Search back through the input to see if it has a proper close
 519                                 // Do this using the reversed string since the other solutions (end anchor, etc.) are inefficient
 520                                 $wsLength = strspn( $revText, " \t", $lengthText - $i );
 521                                 $searchStart = $i - $wsLength;
 522                                 if ( isset( $part->commentEnd ) && $searchStart - 1 == $part->commentEnd ) {
 523                                         // Comment found at line end
 524                                         // Search for equals signs before the comment
 525                                         $searchStart = $part->visualEnd;
 526                                         $searchStart -= strspn( $revText, " \t", $lengthText - $searchStart );
 527                                 }
 528                                 $count = $piece->count;
 529                                 $equalsLength = strspn( $revText, '=', $lengthText - $searchStart );
 530                                 if ( $equalsLength > 0 ) {
 531                                         if ( $searchStart - $equalsLength == $piece->startPos ) {
 532                                                 // This is just a single string of equals signs on its own line
 533                                                 // Replicate the doHeadings behavior /={count}(.+)={count}/
 534                                                 // First find out how many equals signs there really are (don't stop at 6)
 535                                                 $count = $equalsLength;
 536                                                 if ( $count < 3 ) {
 537                                                         $count = 0;
 538                                                 } else {
 539                                                         $count = min( 6, intval( ( $count - 1 ) / 2 ) );
 540                                                 }
 541                                         } else {
 542                                                 $count = min( $equalsLength, $count );
 543                                         }
 544                                         if ( $count > 0 ) {
 545                                                 // Normal match, output <h>
 546                                                 $element = "<h level=\"$count\" i=\"$headingIndex\">$accum</h>";
 547                                                 $headingIndex++;
 548                                         } else {
 549                                                 // Single equals sign on its own line, count=0
 550                                                 $element = $accum;
 551                                         }
 552                                 } else {
 553                                         // No match, no <h>, just pass down the inner text
 554                                         $element = $accum;
 555                                 }
 556                                 // Unwind the stack
 557                                 $stack->pop();
 558                                 $accum =& $stack->getAccum();
 559                                 $flags = $stack->getFlags();
 560                                 extract( $flags );
 561
 562                                 // Append the result to the enclosing accumulator
 563                                 $accum .= $element;
 564                                 // Note that we do NOT increment the input pointer.
 565                                 // This is because the closing linebreak could be the opening linebreak of
 566                                 // another heading. Infinite loops are avoided because the next iteration MUST
 567                                 // hit the heading open case above, which unconditionally increments the
 568                                 // input pointer.
 569                         } elseif ( $found == 'open' ) {
 570                                 # count opening brace characters
 571                                 $count = strspn( $text, $curChar, $i );
 572
 573                                 # we need to add to stack only if opening brace count is enough for one of the rules
 574                                 if ( $count >= $rule['min'] ) {
 575                                         # Add it to the stack
 576                                         $piece = array(
 577                                                 'open' => $curChar,
 578                                                 'close' => $rule['end'],
 579                                                 'count' => $count,
 580                                                 'lineStart' => ($i > 0 && $text[$i - 1] == "\n"),
 581                                         );
 582
 583                                         $stack->push( $piece );
 584                                         $accum =& $stack->getAccum();
 585                                         $flags = $stack->getFlags();
 586                                         extract( $flags );
 587                                 } else {
 588                                         # Add literal brace(s)
 589                                         $accum .= htmlspecialchars( str_repeat( $curChar, $count ) );
 590                                 }
 591                                 $i += $count;
 592                         } elseif ( $found == 'close' ) {
 593                                 $piece = $stack->top;
 594                                 # lets check if there are enough characters for closing brace
 595                                 $maxCount = $piece->count;
 596                                 $count = strspn( $text, $curChar, $i, $maxCount );
 597
 598                                 # check for maximum matching characters (if there are 5 closing
 599                                 # characters, we will probably need only 3 - depending on the rules)
 600                                 $rule = $rules[$piece->open];
 601                                 if ( $count > $rule['max'] ) {
 602                                         # The specified maximum exists in the callback array, unless the caller
 603                                         # has made an error
 604                                         $matchingCount = $rule['max'];
 605                                 } else {
 606                                         # Count is less than the maximum
 607                                         # Skip any gaps in the callback array to find the true largest match
 608                                         # Need to use array_key_exists not isset because the callback can be null
 609                                         $matchingCount = $count;
 610                                         while ( $matchingCount > 0 && !array_key_exists( $matchingCount, $rule['names'] ) ) {
 611                                                 --$matchingCount;
 612                                         }
 613                                 }
 614
 615                                 if ( $matchingCount <= 0 ) {
 616                                         # No matching element found in callback array
 617                                         # Output a literal closing brace and continue
 618                                         $accum .= htmlspecialchars( str_repeat( $curChar, $count ) );
 619                                         $i += $count;
 620                                         continue;
 621                                 }
 622                                 $name = $rule['names'][$matchingCount];
 623                                 if ( $name === null ) {
 624                                         // No element, just literal text
 625                                         $element = $piece->breakSyntax( $matchingCount ) . str_repeat( $rule['end'], $matchingCount );
 626                                 } else {
 627                                         # Create XML element
 628                                         # Note: $parts is already XML, does not need to be encoded further
 629                                         $parts = $piece->parts;
 630                                         $title = $parts[0]->out;
 631                                         unset( $parts[0] );
 632
 633                                         # The invocation is at the start of the line if lineStart is set in
 634                                         # the stack, and all opening brackets are used up.
 635                                         if ( $maxCount == $matchingCount && !empty( $piece->lineStart ) ) {
 636                                                 $attr = ' lineStart="1"';
 637                                         } else {
 638                                                 $attr = '';
 639                                         }
 640
 641                                         $element = "<$name$attr>";
 642                                         $element .= "<title>$title</title>";
 643                                         $argIndex = 1;
 644                                         foreach ( $parts as $part ) {
 645                                                 if ( isset( $part->eqpos ) ) {
 646                                                         $argName = substr( $part->out, 0, $part->eqpos );
 647                                                         $argValue = substr( $part->out, $part->eqpos + 1 );
 648                                                         $element .= "<part><name>$argName</name>=<value>$argValue</value></part>";
 649                                                 } else {
 650                                                         $element .= "<part><name index=\"$argIndex\" /><value>{$part->out}</value></part>";
 651                                                         $argIndex++;
 652                                                 }
 653                                         }
 654                                         $element .= "</$name>";
 655                                 }
 656
 657                                 # Advance input pointer
 658                                 $i += $matchingCount;
 659
 660                                 # Unwind the stack
 661                                 $stack->pop();
 662                                 $accum =& $stack->getAccum();
 663
 664                                 # Re-add the old stack element if it still has unmatched opening characters remaining
 665                                 if ( $matchingCount < $piece->count ) {
 666                                         $piece->parts = array( new PPDPart );
 667                                         $piece->count -= $matchingCount;
 668                                         # do we still qualify for any callback with remaining count?
 669                                         $min = $rules[$piece->open]['min'];
 670                                         if ( $piece->count >= $min ) {
 671                                                 $stack->push( $piece );
 672                                                 $accum =& $stack->getAccum();
 673                                         } else {
 674                                                 $accum .= str_repeat( $piece->open, $piece->count );
 675                                         }
 676                                 }
 677                                 $flags = $stack->getFlags();
 678                                 extract( $flags );
 679
 680                                 # Add XML element to the enclosing accumulator
 681                                 $accum .= $element;
 682                         } elseif ( $found == 'pipe' ) {
 683                                 $findEquals = true; // shortcut for getFlags()
 684                                 $stack->addPart();
 685                                 $accum =& $stack->getAccum();
 686                                 ++$i;
 687                         } elseif ( $found == 'equals' ) {
 688                                 $findEquals = false; // shortcut for getFlags()
 689                                 $stack->getCurrentPart()->eqpos = strlen( $accum );
 690                                 $accum .= '=';
 691                                 ++$i;
 692                         }
 693                 }
 694
 695                 # Output any remaining unclosed brackets
 696                 foreach ( $stack->stack as $piece ) {
 697                         $stack->rootAccum .= $piece->breakSyntax();
 698                 }
 699                 $stack->rootAccum .= '</root>';
 700                 $xml = $stack->rootAccum;
 701
 702                 wfProfileOut( __METHOD__ );
 703
 704                 return $xml;
 705         }
 706 }
 707
 708 /**
 709  * Stack class to help Preprocessor::preprocessToObj()
 710  * @ingroup Parser
 711  */
 712 class PPDStack {
 713         var $stack, $rootAccum;
 714
 715         /**
 716          * @var PPDStack
 717          */
 718         var $top;
 719         var $out;
 720         var $elementClass = 'PPDStackElement';
 721
 722         static $false = false;
 723
 724         function __construct() {
 725                 $this->stack = array();
 726                 $this->top = false;
 727                 $this->rootAccum = '';
 728                 $this->accum =& $this->rootAccum;
 729         }
 730
 731         /**
 732          * @return int
 733          */
 734         function count() {
 735                 return count( $this->stack );
 736         }
 737
 738         function &getAccum() {
 739                 return $this->accum;
 740         }
 741
 742         function getCurrentPart() {
 743                 if ( $this->top === false ) {
 744                         return false;
 745                 } else {
 746                         return $this->top->getCurrentPart();
 747                 }
 748         }
 749
 750         function push( $data ) {
 751                 if ( $data instanceof $this->elementClass ) {
 752                         $this->stack[] = $data;
 753                 } else {
 754                         $class = $this->elementClass;
 755                         $this->stack[] = new $class( $data );
 756                 }
 757                 $this->top = $this->stack[count( $this->stack ) - 1];
 758                 $this->accum =& $this->top->getAccum();
 759         }
 760
 761         function pop() {
 762                 if ( !count( $this->stack ) ) {
 763                         throw new MWException( __METHOD__ . ': no elements remaining' );
 764                 }
 765                 $temp = array_pop( $this->stack );
 766
 767                 if ( count( $this->stack ) ) {
 768                         $this->top = $this->stack[count( $this->stack ) - 1];
 769                         $this->accum =& $this->top->getAccum();
 770                 } else {
 771                         $this->top = self::$false;
 772                         $this->accum =& $this->rootAccum;
 773                 }
 774                 return $temp;
 775         }
 776
 777         function addPart( $s = '' ) {
 778                 $this->top->addPart( $s );
 779                 $this->accum =& $this->top->getAccum();
 780         }
 781
 782         /**
 783          * @return array
 784          */
 785         function getFlags() {
 786                 if ( !count( $this->stack ) ) {
 787                         return array(
 788                                 'findEquals' => false,
 789                                 'findPipe' => false,
 790                                 'inHeading' => false,
 791                         );
 792                 } else {
 793                         return $this->top->getFlags();
 794                 }
 795         }
 796 }
 797
 798 /**
 799  * @ingroup Parser
 800  */
 801 class PPDStackElement {
 802         var     $open,              // Opening character (\n for heading)
 803                 $close,             // Matching closing character
 804                 $count,             // Number of opening characters found (number of "=" for heading)
 805                 $parts,             // Array of PPDPart objects describing pipe-separated parts.
 806                 $lineStart;         // True if the open char appeared at the start of the input line. Not set for headings.
 807
 808         var $partClass = 'PPDPart';
 809
 810         function __construct( $data = array() ) {
 811                 $class = $this->partClass;
 812                 $this->parts = array( new $class );
 813
 814                 foreach ( $data as $name => $value ) {
 815                         $this->$name = $value;
 816                 }
 817         }
 818
 819         function &getAccum() {
 820                 return $this->parts[count( $this->parts ) - 1]->out;
 821         }
 822
 823         function addPart( $s = '' ) {
 824                 $class = $this->partClass;
 825                 $this->parts[] = new $class( $s );
 826         }
 827
 828         function getCurrentPart() {
 829                 return $this->parts[count( $this->parts ) - 1];
 830         }
 831
 832         /**
 833          * @return array
 834          */
 835         function getFlags() {
 836                 $partCount = count( $this->parts );
 837                 $findPipe = $this->open != "\n" && $this->open != '[';
 838                 return array(
 839                         'findPipe' => $findPipe,
 840                         'findEquals' => $findPipe && $partCount > 1 && !isset( $this->parts[$partCount - 1]->eqpos ),
 841                         'inHeading' => $this->open == "\n",
 842                 );
 843         }
 844
 845         /**
 846          * Get the output string that would result if the close is not found.
 847          *
 848          * @return string
 849          */
 850         function breakSyntax( $openingCount = false ) {
 851                 if ( $this->open == "\n" ) {
 852                         $s = $this->parts[0]->out;
 853                 } else {
 854                         if ( $openingCount === false ) {
 855                                 $openingCount = $this->count;
 856                         }
 857                         $s = str_repeat( $this->open, $openingCount );
 858                         $first = true;
 859                         foreach ( $this->parts as $part ) {
 860                                 if ( $first ) {
 861                                         $first = false;
 862                                 } else {
 863                                         $s .= '|';
 864                                 }
 865                                 $s .= $part->out;
 866                         }
 867                 }
 868                 return $s;
 869         }
 870 }
 871
 872 /**
 873  * @ingroup Parser
 874  */
 875 class PPDPart {
 876         var $out; // Output accumulator string
 877
 878         // Optional member variables:
 879         //   eqpos        Position of equals sign in output accumulator
 880         //   commentEnd   Past-the-end input pointer for the last comment encountered
 881         //   visualEnd    Past-the-end input pointer for the end of the accumulator minus comments
 882
 883         function __construct( $out = '' ) {
 884                 $this->out = $out;
 885         }
 886 }
 887
 888 /**
 889  * An expansion frame, used as a context to expand the result of preprocessToObj()
 890  * @ingroup Parser
 891  */
 892 class PPFrame_DOM implements PPFrame {
 893
 894         /**
 895          * @var Preprocessor
 896          */
 897         var $preprocessor;
 898
 899         /**
 900          * @var Parser
 901          */
 902         var $parser;
 903
 904         /**
 905          * @var Title
 906          */
 907         var $title;
 908         var $titleCache;
 909
 910         /**
 911          * Hashtable listing templates which are disallowed for expansion in this frame,
 912          * having been encountered previously in parent frames.
 913          */
 914         var $loopCheckHash;
 915
 916         /**
 917          * Recursion depth of this frame, top = 0
 918          * Note that this is NOT the same as expansion depth in expand()
 919          */
 920         var $depth;
 921
 922         /**
 923          * Construct a new preprocessor frame.
 924          * @param $preprocessor Preprocessor The parent preprocessor
 925          */
 926         function __construct( $preprocessor ) {
 927                 $this->preprocessor = $preprocessor;
 928                 $this->parser = $preprocessor->parser;
 929                 $this->title = $this->parser->mTitle;
 930                 $this->titleCache = array( $this->title ? $this->title->getPrefixedDBkey() : false );
 931                 $this->loopCheckHash = array();
 932                 $this->depth = 0;
 933         }
 934
 935         /**
 936          * Create a new child frame
 937          * $args is optionally a multi-root PPNode or array containing the template arguments
 938          *
 939          * @return PPTemplateFrame_DOM
 940          */
 941         function newChild( $args = false, $title = false, $indexOffset = 0 ) {
 942                 $namedArgs = array();
 943                 $numberedArgs = array();
 944                 if ( $title === false ) {
 945                         $title = $this->title;
 946                 }
 947                 if ( $args !== false ) {
 948                         $xpath = false;
 949                         if ( $args instanceof PPNode ) {
 950                                 $args = $args->node;
 951                         }
 952                         foreach ( $args as $arg ) {
 953                                 if ( $arg instanceof PPNode ) {
 954                                         $arg = $arg->node;
 955                                 }
 956                                 if ( !$xpath ) {
 957                                         $xpath = new DOMXPath( $arg->ownerDocument );
 958                                 }
 959
 960                                 $nameNodes = $xpath->query( 'name', $arg );
 961                                 $value = $xpath->query( 'value', $arg );
 962                                 if ( $nameNodes->item( 0 )->hasAttributes() ) {
 963                                         // Numbered parameter
 964                                         $index = $nameNodes->item( 0 )->attributes->getNamedItem( 'index' )->textContent;
 965                                         $index = $index - $indexOffset;
 966                                         $numberedArgs[$index] = $value->item( 0 );
 967                                         unset( $namedArgs[$index] );
 968                                 } else {
 969                                         // Named parameter
 970                                         $name = trim( $this->expand( $nameNodes->item( 0 ), PPFrame::STRIP_COMMENTS ) );
 971                                         $namedArgs[$name] = $value->item( 0 );
 972                                         unset( $numberedArgs[$name] );
 973                                 }
 974                         }
 975                 }
 976                 return new PPTemplateFrame_DOM( $this->preprocessor, $this, $numberedArgs, $namedArgs, $title );
 977         }
 978
 979         /**
 980          * @throws MWException
 981          * @param $root
 982          * @param $flags int
 983          * @return string
 984          */
 985         function expand( $root, $flags = 0 ) {
 986                 static $expansionDepth = 0;
 987                 if ( is_string( $root ) ) {
 988                         return $root;
 989                 }
 990
 991                 if ( ++$this->parser->mPPNodeCount > $this->parser->mOptions->getMaxPPNodeCount() ) {
 992                         $this->parser->limitationWarn( 'node-count-exceeded',
 993                                 $this->parser->mPPNodeCount,
 994                                 $this->parser->mOptions->getMaxPPNodeCount()
 995                         );
 996                         return '<span class="error">Node-count limit exceeded</span>';
 997                 }
 998
 999                 if ( $expansionDepth > $this->parser->mOptions->getMaxPPExpandDepth() ) {
1000                         $this->parser->limitationWarn( 'expansion-depth-exceeded',
1001                                 $expansionDepth,
1002                                 $this->parser->mOptions->getMaxPPExpandDepth()
1003                         );
1004                         return '<span class="error">Expansion depth limit exceeded</span>';
1005                 }
1006                 wfProfileIn( __METHOD__ );
1007                 ++$expansionDepth;
1008                 if ( $expansionDepth > $this->parser->mHighestExpansionDepth ) {
1009                         $this->parser->mHighestExpansionDepth = $expansionDepth;
1010                 }
1011
1012                 if ( $root instanceof PPNode_DOM ) {
1013                         $root = $root->node;
1014                 }
1015                 if ( $root instanceof DOMDocument ) {
1016                         $root = $root->documentElement;
1017                 }
1018
1019                 $outStack = array( '', '' );
1020                 $iteratorStack = array( false, $root );
1021                 $indexStack = array( 0, 0 );
1022
1023                 while ( count( $iteratorStack ) > 1 ) {
1024                         $level = count( $outStack ) - 1;
1025                         $iteratorNode =& $iteratorStack[$level];
1026                         $out =& $outStack[$level];
1027                         $index =& $indexStack[$level];
1028
1029                         if ( $iteratorNode instanceof PPNode_DOM ) {
1030                                 $iteratorNode = $iteratorNode->node;
1031                         }
1032
1033                         if ( is_array( $iteratorNode ) ) {
1034                                 if ( $index >= count( $iteratorNode ) ) {
1035                                         // All done with this iterator
1036                                         $iteratorStack[$level] = false;
1037                                         $contextNode = false;
1038                                 } else {
1039                                         $contextNode = $iteratorNode[$index];
1040                                         $index++;
1041                                 }
1042                         } elseif ( $iteratorNode instanceof DOMNodeList ) {
1043                                 if ( $index >= $iteratorNode->length ) {
1044                                         // All done with this iterator
1045                                         $iteratorStack[$level] = false;
1046                                         $contextNode = false;
1047                                 } else {
1048                                         $contextNode = $iteratorNode->item( $index );
1049                                         $index++;
1050                                 }
1051                         } else {
1052                                 // Copy to $contextNode and then delete from iterator stack,
1053                                 // because this is not an iterator but we do have to execute it once
1054                                 $contextNode = $iteratorStack[$level];
1055                                 $iteratorStack[$level] = false;
1056                         }
1057
1058                         if ( $contextNode instanceof PPNode_DOM ) {
1059                                 $contextNode = $contextNode->node;
1060                         }
1061
1062                         $newIterator = false;
1063
1064                         if ( $contextNode === false ) {
1065                                 // nothing to do
1066                         } elseif ( is_string( $contextNode ) ) {
1067                                 $out .= $contextNode;
1068                         } elseif ( is_array( $contextNode ) || $contextNode instanceof DOMNodeList ) {
1069                                 $newIterator = $contextNode;
1070                         } elseif ( $contextNode instanceof DOMNode ) {
1071                                 if ( $contextNode->nodeType == XML_TEXT_NODE ) {
1072                                         $out .= $contextNode->nodeValue;
1073                                 } elseif ( $contextNode->nodeName == 'template' ) {
1074                                         # Double-brace expansion
1075                                         $xpath = new DOMXPath( $contextNode->ownerDocument );
1076                                         $titles = $xpath->query( 'title', $contextNode );
1077                                         $title = $titles->item( 0 );
1078                                         $parts = $xpath->query( 'part', $contextNode );
1079                                         if ( $flags & PPFrame::NO_TEMPLATES ) {
1080                                                 $newIterator = $this->virtualBracketedImplode( '{{', '|', '}}', $title, $parts );
1081                                         } else {
1082                                                 $lineStart = $contextNode->getAttribute( 'lineStart' );
1083                                                 $params = array(
1084                                                         'title' => new PPNode_DOM( $title ),
1085                                                         'parts' => new PPNode_DOM( $parts ),
1086                                                         'lineStart' => $lineStart );
1087                                                 $ret = $this->parser->braceSubstitution( $params, $this );
1088                                                 if ( isset( $ret['object'] ) ) {
1089                                                         $newIterator = $ret['object'];
1090                                                 } else {
1091                                                         $out .= $ret['text'];
1092                                                 }
1093                                         }
1094                                 } elseif ( $contextNode->nodeName == 'tplarg' ) {
1095                                         # Triple-brace expansion
1096                                         $xpath = new DOMXPath( $contextNode->ownerDocument );
1097                                         $titles = $xpath->query( 'title', $contextNode );
1098                                         $title = $titles->item( 0 );
1099                                         $parts = $xpath->query( 'part', $contextNode );
1100                                         if ( $flags & PPFrame::NO_ARGS ) {
1101                                                 $newIterator = $this->virtualBracketedImplode( '{{{', '|', '}}}', $title, $parts );
1102                                         } else {
1103                                                 $params = array(
1104                                                         'title' => new PPNode_DOM( $title ),
1105                                                         'parts' => new PPNode_DOM( $parts ) );
1106                                                 $ret = $this->parser->argSubstitution( $params, $this );
1107                                                 if ( isset( $ret['object'] ) ) {
1108                                                         $newIterator = $ret['object'];
1109                                                 } else {
1110                                                         $out .= $ret['text'];
1111                                                 }
1112                                         }
1113                                 } elseif ( $contextNode->nodeName == 'comment' ) {
1114                                         # HTML-style comment
1115                                         # Remove it in HTML, pre+remove and STRIP_COMMENTS modes
1116                                         if ( $this->parser->ot['html']
1117                                                 || ( $this->parser->ot['pre'] && $this->parser->mOptions->getRemoveComments() )
1118                                                 || ( $flags & PPFrame::STRIP_COMMENTS ) )
1119                                         {
1120                                                 $out .= '';
1121                                         }
1122                                         # Add a strip marker in PST mode so that pstPass2() can run some old-fashioned regexes on the result
1123                                         # Not in RECOVER_COMMENTS mode (extractSections) though
1124                                         elseif ( $this->parser->ot['wiki'] && !( $flags & PPFrame::RECOVER_COMMENTS ) ) {
1125                                                 $out .= $this->parser->insertStripItem( $contextNode->textContent );
1126                                         }
1127                                         # Recover the literal comment in RECOVER_COMMENTS and pre+no-remove
1128                                         else {
1129                                                 $out .= $contextNode->textContent;
1130                                         }
1131                                 } elseif ( $contextNode->nodeName == 'ignore' ) {
1132                                         # Output suppression used by <includeonly> etc.
1133                                         # OT_WIKI will only respect <ignore> in substed templates.
1134                                         # The other output types respect it unless NO_IGNORE is set.
1135                                         # extractSections() sets NO_IGNORE and so never respects it.
1136                                         if ( ( !isset( $this->parent ) && $this->parser->ot['wiki'] ) || ( $flags & PPFrame::NO_IGNORE ) ) {
1137                                                 $out .= $contextNode->textContent;
1138                                         } else {
1139                                                 $out .= '';
1140                                         }
1141                                 } elseif ( $contextNode->nodeName == 'ext' ) {
1142                                         # Extension tag
1143                                         $xpath = new DOMXPath( $contextNode->ownerDocument );
1144                                         $names = $xpath->query( 'name', $contextNode );
1145                                         $attrs = $xpath->query( 'attr', $contextNode );
1146                                         $inners = $xpath->query( 'inner', $contextNode );
1147                                         $closes = $xpath->query( 'close', $contextNode );
1148                                         $params = array(
1149                                                 'name' => new PPNode_DOM( $names->item( 0 ) ),
1150                                                 'attr' => $attrs->length > 0 ? new PPNode_DOM( $attrs->item( 0 ) ) : null,
1151                                                 'inner' => $inners->length > 0 ? new PPNode_DOM( $inners->item( 0 ) ) : null,
1152                                                 'close' => $closes->length > 0 ? new PPNode_DOM( $closes->item( 0 ) ) : null,
1153                                         );
1154                                         $out .= $this->parser->extensionSubstitution( $params, $this );
1155                                 } elseif ( $contextNode->nodeName == 'h' ) {
1156                                         # Heading
1157                                         $s = $this->expand( $contextNode->childNodes, $flags );
1158
1159                                         # Insert a heading marker only for <h> children of <root>
1160                                         # This is to stop extractSections from going over multiple tree levels
1161                                         if ( $contextNode->parentNode->nodeName == 'root' && $this->parser->ot['html'] ) {
1162                                                 # Insert heading index marker
1163                                                 $headingIndex = $contextNode->getAttribute( 'i' );
1164                                                 $titleText = $this->title->getPrefixedDBkey();
1165                                                 $this->parser->mHeadings[] = array( $titleText, $headingIndex );
1166                                                 $serial = count( $this->parser->mHeadings ) - 1;
1167                                                 $marker = "{$this->parser->mUniqPrefix}-h-$serial-" . Parser::MARKER_SUFFIX;
1168                                                 $count = $contextNode->getAttribute( 'level' );
1169                                                 $s = substr( $s, 0, $count ) . $marker . substr( $s, $count );
1170                                                 $this->parser->mStripState->addGeneral( $marker, '' );
1171                                         }
1172                                         $out .= $s;
1173                                 } else {
1174                                         # Generic recursive expansion
1175                                         $newIterator = $contextNode->childNodes;
1176                                 }
1177                         } else {
1178                                 wfProfileOut( __METHOD__ );
1179                                 throw new MWException( __METHOD__ . ': Invalid parameter type' );
1180                         }
1181
1182                         if ( $newIterator !== false ) {
1183                                 if ( $newIterator instanceof PPNode_DOM ) {
1184                                         $newIterator = $newIterator->node;
1185                                 }
1186                                 $outStack[] = '';
1187                                 $iteratorStack[] = $newIterator;
1188                                 $indexStack[] = 0;
1189                         } elseif ( $iteratorStack[$level] === false ) {
1190                                 // Return accumulated value to parent
1191                                 // With tail recursion
1192                                 while ( $iteratorStack[$level] === false && $level > 0 ) {
1193                                         $outStack[$level - 1] .= $out;
1194                                         array_pop( $outStack );
1195                                         array_pop( $iteratorStack );
1196                                         array_pop( $indexStack );
1197                                         $level--;
1198                                 }
1199                         }
1200                 }
1201                 --$expansionDepth;
1202                 wfProfileOut( __METHOD__ );
1203                 return $outStack[0];
1204         }
1205
1206         /**
1207          * @param $sep
1208          * @param $flags
1209          * @return string
1210          */
1211         function implodeWithFlags( $sep, $flags /*, ... */ ) {
1212                 $args = array_slice( func_get_args(), 2 );
1213
1214                 $first = true;
1215                 $s = '';
1216                 foreach ( $args as $root ) {
1217                         if ( $root instanceof PPNode_DOM ) $root = $root->node;
1218                         if ( !is_array( $root ) && !( $root instanceof DOMNodeList ) ) {
1219                                 $root = array( $root );
1220                         }
1221                         foreach ( $root as $node ) {
1222                                 if ( $first ) {
1223                                         $first = false;
1224                                 } else {
1225                                         $s .= $sep;
1226                                 }
1227                                 $s .= $this->expand( $node, $flags );
1228                         }
1229                 }
1230                 return $s;
1231         }
1232
1233         /**
1234          * Implode with no flags specified
1235          * This previously called implodeWithFlags but has now been inlined to reduce stack depth
1236          *
1237          * @return string
1238          */
1239         function implode( $sep /*, ... */ ) {
1240                 $args = array_slice( func_get_args(), 1 );
1241
1242                 $first = true;
1243                 $s = '';
1244                 foreach ( $args as $root ) {
1245                         if ( $root instanceof PPNode_DOM ) {
1246                                 $root = $root->node;
1247                         }
1248                         if ( !is_array( $root ) && !( $root instanceof DOMNodeList ) ) {
1249                                 $root = array( $root );
1250                         }
1251                         foreach ( $root as $node ) {
1252                                 if ( $first ) {
1253                                         $first = false;
1254                                 } else {
1255                                         $s .= $sep;
1256                                 }
1257                                 $s .= $this->expand( $node );
1258                         }
1259                 }
1260                 return $s;
1261         }
1262
1263         /**
1264          * Makes an object that, when expand()ed, will be the same as one obtained
1265          * with implode()
1266          *
1267          * @return array
1268          */
1269         function virtualImplode( $sep /*, ... */ ) {
1270                 $args = array_slice( func_get_args(), 1 );
1271                 $out = array();
1272                 $first = true;
1273
1274                 foreach ( $args as $root ) {
1275                         if ( $root instanceof PPNode_DOM ) {
1276                                 $root = $root->node;
1277                         }
1278                         if ( !is_array( $root ) && !( $root instanceof DOMNodeList ) ) {
1279                                 $root = array( $root );
1280                         }
1281                         foreach ( $root as $node ) {
1282                                 if ( $first ) {
1283                                         $first = false;
1284                                 } else {
1285                                         $out[] = $sep;
1286                                 }
1287                                 $out[] = $node;
1288                         }
1289                 }
1290                 return $out;
1291         }
1292
1293         /**
1294          * Virtual implode with brackets
1295          * @return array
1296          */
1297         function virtualBracketedImplode( $start, $sep, $end /*, ... */ ) {
1298                 $args = array_slice( func_get_args(), 3 );
1299                 $out = array( $start );
1300                 $first = true;
1301
1302                 foreach ( $args as $root ) {
1303                         if ( $root instanceof PPNode_DOM ) {
1304                                 $root = $root->node;
1305                         }
1306                         if ( !is_array( $root ) && !( $root instanceof DOMNodeList ) ) {
1307                                 $root = array( $root );
1308                         }
1309                         foreach ( $root as $node ) {
1310                                 if ( $first ) {
1311                                         $first = false;
1312                                 } else {
1313                                         $out[] = $sep;
1314                                 }
1315                                 $out[] = $node;
1316                         }
1317                 }
1318                 $out[] = $end;
1319                 return $out;
1320         }
1321
1322         function __toString() {
1323                 return 'frame{}';
1324         }
1325
1326         function getPDBK( $level = false ) {
1327                 if ( $level === false ) {
1328                         return $this->title->getPrefixedDBkey();
1329                 } else {
1330                         return isset( $this->titleCache[$level] ) ? $this->titleCache[$level] : false;
1331                 }
1332         }
1333
1334         /**
1335          * @return array
1336          */
1337         function getArguments() {
1338                 return array();
1339         }
1340
1341         /**
1342          * @return array
1343          */
1344         function getNumberedArguments() {
1345                 return array();
1346         }
1347
1348         /**
1349          * @return array
1350          */
1351         function getNamedArguments() {
1352                 return array();
1353         }
1354
1355         /**
1356          * Returns true if there are no arguments in this frame
1357          *
1358          * @return bool
1359          */
1360         function isEmpty() {
1361                 return true;
1362         }
1363
1364         function getArgument( $name ) {
1365                 return false;
1366         }
1367
1368         /**
1369          * Returns true if the infinite loop check is OK, false if a loop is detected
1370          *
1371          * @return bool
1372          */
1373         function loopCheck( $title ) {
1374                 return !isset( $this->loopCheckHash[$title->getPrefixedDBkey()] );
1375         }
1376
1377         /**
1378          * Return true if the frame is a template frame
1379          *
1380          * @return bool
1381          */
1382         function isTemplate() {
1383                 return false;
1384         }
1385
1386         /**
1387          * Get a title of frame
1388          *
1389          * @return Title
1390          */
1391         function getTitle() {
1392                 return $this->title;
1393         }
1394 }
1395
1396 /**
1397  * Expansion frame with template arguments
1398  * @ingroup Parser
1399  */
1400 class PPTemplateFrame_DOM extends PPFrame_DOM {
1401         var $numberedArgs, $namedArgs;
1402
1403         /**
1404          * @var PPFrame_DOM
1405          */
1406         var $parent;
1407         var $numberedExpansionCache, $namedExpansionCache;
1408
1409         /**
1410          * @param $preprocessor
1411          * @param $parent PPFrame_DOM
1412          * @param $numberedArgs array
1413          * @param $namedArgs array
1414          * @param $title Title
1415          */
1416         function __construct( $preprocessor, $parent = false, $numberedArgs = array(), $namedArgs = array(), $title = false ) {
1417                 parent::__construct( $preprocessor );
1418
1419                 $this->parent = $parent;
1420                 $this->numberedArgs = $numberedArgs;
1421                 $this->namedArgs = $namedArgs;
1422                 $this->title = $title;
1423                 $pdbk = $title ? $title->getPrefixedDBkey() : false;
1424                 $this->titleCache = $parent->titleCache;
1425                 $this->titleCache[] = $pdbk;
1426                 $this->loopCheckHash = /*clone*/ $parent->loopCheckHash;
1427                 if ( $pdbk !== false ) {
1428                         $this->loopCheckHash[$pdbk] = true;
1429                 }
1430                 $this->depth = $parent->depth + 1;
1431                 $this->numberedExpansionCache = $this->namedExpansionCache = array();
1432         }
1433
1434         function __toString() {
1435                 $s = 'tplframe{';
1436                 $first = true;
1437                 $args = $this->numberedArgs + $this->namedArgs;
1438                 foreach ( $args as $name => $value ) {
1439                         if ( $first ) {
1440                                 $first = false;
1441                         } else {
1442                                 $s .= ', ';
1443                         }
1444                         $s .= "\"$name\":\"" .
1445                                 str_replace( '"', '\\"', $value->ownerDocument->saveXML( $value ) ) . '"';
1446                 }
1447                 $s .= '}';
1448                 return $s;
1449         }
1450
1451         /**
1452          * Returns true if there are no arguments in this frame
1453          *
1454          * @return bool
1455          */
1456         function isEmpty() {
1457                 return !count( $this->numberedArgs ) && !count( $this->namedArgs );
1458         }
1459
1460         function getArguments() {
1461                 $arguments = array();
1462                 foreach ( array_merge(
1463                                 array_keys( $this->numberedArgs ),
1464                                 array_keys( $this->namedArgs ) ) as $key ) {
1465                         $arguments[$key] = $this->getArgument( $key );
1466                 }
1467                 return $arguments;
1468         }
1469
1470         function getNumberedArguments() {
1471                 $arguments = array();
1472                 foreach ( array_keys( $this->numberedArgs ) as $key ) {
1473                         $arguments[$key] = $this->getArgument( $key );
1474                 }
1475                 return $arguments;
1476         }
1477
1478         function getNamedArguments() {
1479                 $arguments = array();
1480                 foreach ( array_keys( $this->namedArgs ) as $key ) {
1481                         $arguments[$key] = $this->getArgument( $key );
1482                 }
1483                 return $arguments;
1484         }
1485
1486         function getNumberedArgument( $index ) {
1487                 if ( !isset( $this->numberedArgs[$index] ) ) {
1488                         return false;
1489                 }
1490                 if ( !isset( $this->numberedExpansionCache[$index] ) ) {
1491                         # No trimming for unnamed arguments
1492                         $this->numberedExpansionCache[$index] = $this->parent->expand( $this->numberedArgs[$index], PPFrame::STRIP_COMMENTS );
1493                 }
1494                 return $this->numberedExpansionCache[$index];
1495         }
1496
1497         function getNamedArgument( $name ) {
1498                 if ( !isset( $this->namedArgs[$name] ) ) {
1499                         return false;
1500                 }
1501                 if ( !isset( $this->namedExpansionCache[$name] ) ) {
1502                         # Trim named arguments post-expand, for backwards compatibility
1503                         $this->namedExpansionCache[$name] = trim(
1504                                 $this->parent->expand( $this->namedArgs[$name], PPFrame::STRIP_COMMENTS ) );
1505                 }
1506                 return $this->namedExpansionCache[$name];
1507         }
1508
1509         function getArgument( $name ) {
1510                 $text = $this->getNumberedArgument( $name );
1511                 if ( $text === false ) {
1512                         $text = $this->getNamedArgument( $name );
1513                 }
1514                 return $text;
1515         }
1516
1517         /**
1518          * Return true if the frame is a template frame
1519          *
1520          * @return bool
1521          */
1522         function isTemplate() {
1523                 return true;
1524         }
1525 }
1526
1527 /**
1528  * Expansion frame with custom arguments
1529  * @ingroup Parser
1530  */
1531 class PPCustomFrame_DOM extends PPFrame_DOM {
1532         var $args;
1533
1534         function __construct( $preprocessor, $args ) {
1535                 parent::__construct( $preprocessor );
1536                 $this->args = $args;
1537         }
1538
1539         function __toString() {
1540                 $s = 'cstmframe{';
1541                 $first = true;
1542                 foreach ( $this->args as $name => $value ) {
1543                         if ( $first ) {
1544                                 $first = false;
1545                         } else {
1546                                 $s .= ', ';
1547                         }
1548                         $s .= "\"$name\":\"" .
1549                                 str_replace( '"', '\\"', $value->__toString() ) . '"';
1550                 }
1551                 $s .= '}';
1552                 return $s;
1553         }
1554
1555         /**
1556          * @return bool
1557          */
1558         function isEmpty() {
1559                 return !count( $this->args );
1560         }
1561
1562         function getArgument( $index ) {
1563                 if ( !isset( $this->args[$index] ) ) {
1564                         return false;
1565                 }
1566                 return $this->args[$index];
1567         }
1568
1569         function getArguments() {
1570                 return $this->args;
1571         }
1572 }
1573
1574 /**
1575  * @ingroup Parser
1576  */
1577 class PPNode_DOM implements PPNode {
1578
1579         /**
1580          * @var DOMElement
1581          */
1582         var $node;
1583         var $xpath;
1584
1585         function __construct( $node, $xpath = false ) {
1586                 $this->node = $node;
1587         }
1588
1589         /**
1590          * @return DOMXPath
1591          */
1592         function getXPath() {
1593                 if ( $this->xpath === null ) {
1594                         $this->xpath = new DOMXPath( $this->node->ownerDocument );
1595                 }
1596                 return $this->xpath;
1597         }
1598
1599         function __toString() {
1600                 if ( $this->node instanceof DOMNodeList ) {
1601                         $s = '';
1602                         foreach ( $this->node as $node ) {
1603                                 $s .= $node->ownerDocument->saveXML( $node );
1604                         }
1605                 } else {
1606                         $s = $this->node->ownerDocument->saveXML( $this->node );
1607                 }
1608                 return $s;
1609         }
1610
1611         /**
1612          * @return bool|PPNode_DOM
1613          */
1614         function getChildren() {
1615                 return $this->node->childNodes ? new self( $this->node->childNodes ) : false;
1616         }
1617
1618         /**
1619          * @return bool|PPNode_DOM
1620          */
1621         function getFirstChild() {
1622                 return $this->node->firstChild ? new self( $this->node->firstChild ) : false;
1623         }
1624
1625         /**
1626          * @return bool|PPNode_DOM
1627          */
1628         function getNextSibling() {
1629                 return $this->node->nextSibling ? new self( $this->node->nextSibling ) : false;
1630         }
1631
1632         /**
1633          * @param $type
1634          *
1635          * @return bool|PPNode_DOM
1636          */
1637         function getChildrenOfType( $type ) {
1638                 return new self( $this->getXPath()->query( $type, $this->node ) );
1639         }
1640
1641         /**
1642          * @return int
1643          */
1644         function getLength() {
1645                 if ( $this->node instanceof DOMNodeList ) {
1646                         return $this->node->length;
1647                 } else {
1648                         return false;
1649                 }
1650         }
1651
1652         /**
1653          * @param $i
1654          * @return bool|PPNode_DOM
1655          */
1656         function item( $i ) {
1657                 $item = $this->node->item( $i );
1658                 return $item ? new self( $item ) : false;
1659         }
1660
1661         /**
1662          * @return string
1663          */
1664         function getName() {
1665                 if ( $this->node instanceof DOMNodeList ) {
1666                         return '#nodelist';
1667                 } else {
1668                         return $this->node->nodeName;
1669                 }
1670         }
1671
1672         /**
1673          * Split a "<part>" node into an associative array containing:
1674          *  - name          PPNode name
1675          *  - index         String index
1676          *  - value         PPNode value
1677          *
1678          * @throws MWException
1679          * @return array
1680          */
1681         function splitArg() {
1682                 $xpath = $this->getXPath();
1683                 $names = $xpath->query( 'name', $this->node );
1684                 $values = $xpath->query( 'value', $this->node );
1685                 if ( !$names->length || !$values->length ) {
1686                         throw new MWException( 'Invalid brace node passed to ' . __METHOD__ );
1687                 }
1688                 $name = $names->item( 0 );
1689                 $index = $name->getAttribute( 'index' );
1690                 return array(
1691                         'name' => new self( $name ),
1692                         'index' => $index,
1693                         'value' => new self( $values->item( 0 ) ) );
1694         }
1695
1696         /**
1697          * Split an "<ext>" node into an associative array containing name, attr, inner and close
1698          * All values in the resulting array are PPNodes. Inner and close are optional.
1699          *
1700          * @throws MWException
1701          * @return array
1702          */
1703         function splitExt() {
1704                 $xpath = $this->getXPath();
1705                 $names = $xpath->query( 'name', $this->node );
1706                 $attrs = $xpath->query( 'attr', $this->node );
1707                 $inners = $xpath->query( 'inner', $this->node );
1708                 $closes = $xpath->query( 'close', $this->node );
1709                 if ( !$names->length || !$attrs->length ) {
1710                         throw new MWException( 'Invalid ext node passed to ' . __METHOD__ );
1711                 }
1712                 $parts = array(
1713                         'name' => new self( $names->item( 0 ) ),
1714                         'attr' => new self( $attrs->item( 0 ) ) );
1715                 if ( $inners->length ) {
1716                         $parts['inner'] = new self( $inners->item( 0 ) );
1717                 }
1718                 if ( $closes->length ) {
1719                         $parts['close'] = new self( $closes->item( 0 ) );
1720                 }
1721                 return $parts;
1722         }
1723
1724         /**
1725          * Split a "<h>" node
1726          * @throws MWException
1727          * @return array
1728          */
1729         function splitHeading() {
1730                 if ( $this->getName() !== 'h' ) {
1731                         throw new MWException( 'Invalid h node passed to ' . __METHOD__ );
1732                 }
1733                 return array(
1734                         'i' => $this->node->getAttribute( 'i' ),
1735                         'level' => $this->node->getAttribute( 'level' ),
1736                         'contents' => $this->getChildren()
1737                 );
1738         }
1739 }