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
  76                         if ( is_int( $k ) ) {
  77                                 $xml .= "<part><name index=\"$k\"/><value>" . htmlspecialchars( $val ) ."</value></part>";
  78                         } else {
  79                                 $xml .= "<part><name>" . htmlspecialchars( $k ) . "</name>=<value>" . htmlspecialchars( $val ) . "</value></part>";
  80                         }
  81                 }
  82
  83                 $xml .= "</list>";
  84
  85                 $dom = new DOMDocument();
  86                 $dom->loadXML( $xml );
  87                 $root = $dom->documentElement;
  88
  89                 $node = new PPNode_DOM( $root->childNodes );
  90                 return $node;
  91         }
  92
  93         /**
  94          * @throws MWException
  95          * @return bool
  96          */
  97         function memCheck() {
  98                 if ( $this->memoryLimit === false ) {
  99                         return true;
 100                 }
 101                 $usage = memory_get_usage();
 102                 if ( $usage > $this->memoryLimit * 0.9 ) {
 103                         $limit = intval( $this->memoryLimit * 0.9 / 1048576 + 0.5 );
 104                         throw new MWException( "Preprocessor hit 90% memory limit ($limit MB)" );
 105                 }
 106                 return $usage <= $this->memoryLimit * 0.8;
 107         }
 108
 109         /**
 110          * Preprocess some wikitext and return the document tree.
 111          * This is the ghost of Parser::replace_variables().
 112          *
 113          * @param string $text the text to parse
 114          * @param $flags Integer: bitwise combination of:
 115          *          Parser::PTD_FOR_INCLUSION    Handle "<noinclude>" and "<includeonly>" as if the text is being
 116          *                                     included. Default is to assume a direct page view.
 117          *
 118          * The generated DOM tree must depend only on the input text and the flags.
 119          * The DOM tree must be the same in OT_HTML and OT_WIKI mode, to avoid a regression of bug 4899.
 120          *
 121          * Any flag added to the $flags parameter here, or any other parameter liable to cause a
 122          * change in the DOM tree for a given text, must be passed through the section identifier
 123          * in the section edit link and thus back to extractSections().
 124          *
 125          * The output of this function is currently only cached in process memory, but a persistent
 126          * cache may be implemented at a later date which takes further advantage of these strict
 127          * dependency requirements.
 128          *
 129          * @throws MWException
 130          * @return PPNode_DOM
 131          */
 132         function preprocessToObj( $text, $flags = 0 ) {
 133                 wfProfileIn( __METHOD__ );
 134                 global $wgMemc, $wgPreprocessorCacheThreshold;
 135
 136                 $xml = false;
 137                 $cacheable = ( $wgPreprocessorCacheThreshold !== false
 138                         && strlen( $text ) > $wgPreprocessorCacheThreshold );
 139                 if ( $cacheable ) {
 140                         wfProfileIn( __METHOD__ . '-cacheable' );
 141
 142                         $cacheKey = wfMemcKey( 'preprocess-xml', md5( $text ), $flags );
 143                         $cacheValue = $wgMemc->get( $cacheKey );
 144                         if ( $cacheValue ) {
 145                                 $version = substr( $cacheValue, 0, 8 );
 146                                 if ( intval( $version ) == self::CACHE_VERSION ) {
 147                                         $xml = substr( $cacheValue, 8 );
 148                                         // From the cache
 149                                         wfDebugLog( "Preprocessor", "Loaded preprocessor XML from memcached (key $cacheKey)" );
 150                                 }
 151                         }
 152                 }
 153                 if ( $xml === false ) {
 154                         if ( $cacheable ) {
 155                                 wfProfileIn( __METHOD__ . '-cache-miss' );
 156                                 $xml = $this->preprocessToXml( $text, $flags );
 157                                 $cacheValue = sprintf( "%08d", self::CACHE_VERSION ) . $xml;
 158                                 $wgMemc->set( $cacheKey, $cacheValue, 86400 );
 159                                 wfProfileOut( __METHOD__ . '-cache-miss' );
 160                                 wfDebugLog( "Preprocessor", "Saved preprocessor XML to memcached (key $cacheKey)" );
 161                         } else {
 162                                 $xml = $this->preprocessToXml( $text, $flags );
 163                         }
 164
 165                 }
 166
 167                 // Fail if the number of elements exceeds acceptable limits
 168                 // Do not attempt to generate the DOM
 169                 $this->parser->mGeneratedPPNodeCount += substr_count( $xml, '<' );
 170                 $max = $this->parser->mOptions->getMaxGeneratedPPNodeCount();
 171                 if ( $this->parser->mGeneratedPPNodeCount > $max ) {
 172                         if ( $cacheable ) {
 173                                 wfProfileOut( __METHOD__ . '-cacheable' );
 174                         }
 175                         wfProfileOut( __METHOD__ );
 176                         throw new MWException( __METHOD__ . ': generated node count limit exceeded' );
 177                 }
 178
 179                 wfProfileIn( __METHOD__ . '-loadXML' );
 180                 $dom = new DOMDocument;
 181                 wfSuppressWarnings();
 182                 $result = $dom->loadXML( $xml );
 183                 wfRestoreWarnings();
 184                 if ( !$result ) {
 185                         // Try running the XML through UtfNormal to get rid of invalid characters
 186                         $xml = UtfNormal::cleanUp( $xml );
 187                         // 1 << 19 == XML_PARSE_HUGE, needed so newer versions of libxml2 don't barf when the XML is >256 levels deep
 188                         $result = $dom->loadXML( $xml, 1 << 19 );
 189                         if ( !$result ) {
 190                                 wfProfileOut( __METHOD__ . '-loadXML' );
 191                                 if ( $cacheable ) {
 192                                         wfProfileOut( __METHOD__ . '-cacheable' );
 193                                 }
 194                                 wfProfileOut( __METHOD__ );
 195                                 throw new MWException( __METHOD__ . ' generated invalid XML' );
 196                         }
 197                 }
 198                 $obj = new PPNode_DOM( $dom->documentElement );
 199                 wfProfileOut( __METHOD__ . '-loadXML' );
 200                 if ( $cacheable ) {
 201                         wfProfileOut( __METHOD__ . '-cacheable' );
 202                 }
 203                 wfProfileOut( __METHOD__ );
 204                 return $obj;
 205         }
 206
 207         /**
 208          * @param $text string
 209          * @param $flags int
 210          * @return string
 211          */
 212         function preprocessToXml( $text, $flags = 0 ) {
 213                 wfProfileIn( __METHOD__ );
 214                 $rules = array(
 215                         '{' => array(
 216                                 'end' => '}',
 217                                 'names' => array(
 218                                         2 => 'template',
 219                                         3 => 'tplarg',
 220                                 ),
 221                                 'min' => 2,
 222                                 'max' => 3,
 223                         ),
 224                         '[' => array(
 225                                 'end' => ']',
 226                                 'names' => array( 2 => null ),
 227                                 'min' => 2,
 228                                 'max' => 2,
 229                         )
 230                 );
 231
 232                 $forInclusion = $flags & Parser::PTD_FOR_INCLUSION;
 233
 234                 $xmlishElements = $this->parser->getStripList();
 235                 $enableOnlyinclude = false;
 236                 if ( $forInclusion ) {
 237                         $ignoredTags = array( 'includeonly', '/includeonly' );
 238                         $ignoredElements = array( 'noinclude' );
 239                         $xmlishElements[] = 'noinclude';
 240                         if ( strpos( $text, '<onlyinclude>' ) !== false && strpos( $text, '</onlyinclude>' ) !== false ) {
 241                                 $enableOnlyinclude = true;
 242                         }
 243                 } else {
 244                         $ignoredTags = array( 'noinclude', '/noinclude', 'onlyinclude', '/onlyinclude' );
 245                         $ignoredElements = array( 'includeonly' );
 246                         $xmlishElements[] = 'includeonly';
 247                 }
 248                 $xmlishRegex = implode( '|', array_merge( $xmlishElements, $ignoredTags ) );
 249
 250                 // Use "A" modifier (anchored) instead of "^", because ^ doesn't work with an offset
 251                 $elementsRegex = "~($xmlishRegex)(?:\s|\/>|>)|(!--)~iA";
 252
 253                 $stack = new PPDStack;
 254
 255                 $searchBase = "[{<\n"; #}
 256                 $revText = strrev( $text ); // For fast reverse searches
 257                 $lengthText = strlen( $text );
 258
 259                 $i = 0;                     # Input pointer, starts out pointing to a pseudo-newline before the start
 260                 $accum =& $stack->getAccum();   # Current accumulator
 261                 $accum = '<root>';
 262                 $findEquals = false;            # True to find equals signs in arguments
 263                 $findPipe = false;              # True to take notice of pipe characters
 264                 $headingIndex = 1;
 265                 $inHeading = false;        # True if $i is inside a possible heading
 266                 $noMoreGT = false;         # True if there are no more greater-than (>) signs right of $i
 267                 $findOnlyinclude = $enableOnlyinclude; # True to ignore all input up to the next <onlyinclude>
 268                 $fakeLineStart = true;     # Do a line-start run without outputting an LF character
 269
 270                 while ( true ) {
 271                         //$this->memCheck();
 272
 273                         if ( $findOnlyinclude ) {
 274                                 // Ignore all input up to the next <onlyinclude>
 275                                 $startPos = strpos( $text, '<onlyinclude>', $i );
 276                                 if ( $startPos === false ) {
 277                                         // Ignored section runs to the end
 278                                         $accum .= '<ignore>' . htmlspecialchars( substr( $text, $i ) ) . '</ignore>';
 279                                         break;
 280                                 }
 281                                 $tagEndPos = $startPos + strlen( '<onlyinclude>' ); // past-the-end
 282                                 $accum .= '<ignore>' . htmlspecialchars( substr( $text, $i, $tagEndPos - $i ) ) . '</ignore>';
 283                                 $i = $tagEndPos;
 284                                 $findOnlyinclude = false;
 285                         }
 286
 287                         if ( $fakeLineStart ) {
 288                                 $found = 'line-start';
 289                                 $curChar = '';
 290                         } else {
 291                                 # Find next opening brace, closing brace or pipe
 292                                 $search = $searchBase;
 293                                 if ( $stack->top === false ) {
 294                                         $currentClosing = '';
 295                                 } else {
 296                                         $currentClosing = $stack->top->close;
 297                                         $search .= $currentClosing;
 298                                 }
 299                                 if ( $findPipe ) {
 300                                         $search .= '|';
 301                                 }
 302                                 if ( $findEquals ) {
 303                                         // First equals will be for the template
 304                                         $search .= '=';
 305                                 }
 306                                 $rule = null;
 307                                 # Output literal section, advance input counter
 308                                 $literalLength = strcspn( $text, $search, $i );
 309                                 if ( $literalLength > 0 ) {
 310                                         $accum .= htmlspecialchars( substr( $text, $i, $literalLength ) );
 311                                         $i += $literalLength;
 312                                 }
 313                                 if ( $i >= $lengthText ) {
 314                                         if ( $currentClosing == "\n" ) {
 315                                                 // Do a past-the-end run to finish off the heading
 316                                                 $curChar = '';
 317                                                 $found = 'line-end';
 318                                         } else {
 319                                                 # All done
 320                                                 break;
 321                                         }
 322                                 } else {
 323                                         $curChar = $text[$i];
 324                                         if ( $curChar == '|' ) {
 325                                                 $found = 'pipe';
 326                                         } elseif ( $curChar == '=' ) {
 327                                                 $found = 'equals';
 328                                         } elseif ( $curChar == '<' ) {
 329                                                 $found = 'angle';
 330                                         } elseif ( $curChar == "\n" ) {
 331                                                 if ( $inHeading ) {
 332                                                         $found = 'line-end';
 333                                                 } else {
 334                                                         $found = 'line-start';
 335                                                 }
 336                                         } elseif ( $curChar == $currentClosing ) {
 337                                                 $found = 'close';
 338                                         } elseif ( isset( $rules[$curChar] ) ) {
 339                                                 $found = 'open';
 340                                                 $rule = $rules[$curChar];
 341                                         } else {
 342                                                 # Some versions of PHP have a strcspn which stops on null characters
 343                                                 # Ignore and continue
 344                                                 ++$i;
 345                                                 continue;
 346                                         }
 347                                 }
 348                         }
 349
 350                         if ( $found == 'angle' ) {
 351                                 $matches = false;
 352                                 // Handle </onlyinclude>
 353                                 if ( $enableOnlyinclude && substr( $text, $i, strlen( '</onlyinclude>' ) ) == '</onlyinclude>' ) {
 354                                         $findOnlyinclude = true;
 355                                         continue;
 356                                 }
 357
 358                                 // Determine element name
 359                                 if ( !preg_match( $elementsRegex, $text, $matches, 0, $i + 1 ) ) {
 360                                         // Element name missing or not listed
 361                                         $accum .= '&lt;';
 362                                         ++$i;
 363                                         continue;
 364                                 }
 365                                 // Handle comments
 366                                 if ( isset( $matches[2] ) && $matches[2] == '!--' ) {
 367                                         // To avoid leaving blank lines, when a comment is both preceded
 368                                         // and followed by a newline (ignoring spaces), trim leading and
 369                                         // trailing spaces and one of the newlines.
 370
 371                                         // Find the end
 372                                         $endPos = strpos( $text, '-->', $i + 4 );
 373                                         if ( $endPos === false ) {
 374                                                 // Unclosed comment in input, runs to end
 375                                                 $inner = substr( $text, $i );
 376                                                 $accum .= '<comment>' . htmlspecialchars( $inner ) . '</comment>';
 377                                                 $i = $lengthText;
 378                                         } else {
 379                                                 // Search backwards for leading whitespace
 380                                                 $wsStart = $i ? ( $i - strspn( $revText, ' ', $lengthText - $i ) ) : 0;
 381                                                 // Search forwards for trailing whitespace
 382                                                 // $wsEnd will be the position of the last space (or the '>' if there's none)
 383                                                 $wsEnd = $endPos + 2 + strspn( $text, ' ', $endPos + 3 );
 384                                                 // Eat the line if possible
 385                                                 // TODO: This could theoretically be done if $wsStart == 0, i.e. for comments at
 386                                                 // the overall start. That's not how Sanitizer::removeHTMLcomments() did it, but
 387                                                 // it's a possible beneficial b/c break.
 388                                                 if ( $wsStart > 0 && substr( $text, $wsStart - 1, 1 ) == "\n"
 389                                                         && substr( $text, $wsEnd + 1, 1 ) == "\n" )
 390                                                 {
 391                                                         $startPos = $wsStart;
 392                                                         $endPos = $wsEnd + 1;
 393                                                         // Remove leading whitespace from the end of the accumulator
 394                                                         // Sanity check first though
 395                                                         $wsLength = $i - $wsStart;
 396                                                         if ( $wsLength > 0 && substr( $accum, -$wsLength ) === str_repeat( ' ', $wsLength ) ) {
 397                                                                 $accum = substr( $accum, 0, -$wsLength );
 398                                                         }
 399                                                         // Do a line-start run next time to look for headings after the comment
 400                                                         $fakeLineStart = true;
 401                                                 } else {
 402                                                         // No line to eat, just take the comment itself
 403                                                         $startPos = $i;
 404                                                         $endPos += 2;
 405                                                 }
 406
 407                                                 if ( $stack->top ) {
 408                                                         $part = $stack->top->getCurrentPart();
 409                                                         if ( !( isset( $part->commentEnd ) && $part->commentEnd == $wsStart - 1 ) ) {
 410                                                                 $part->visualEnd = $wsStart;
 411                                                         }
 412                                                         // Else comments abutting, no change in visual end
 413                                                         $part->commentEnd = $endPos;
 414                                                 }
 415                                                 $i = $endPos + 1;
 416                                                 $inner = substr( $text, $startPos, $endPos - $startPos + 1 );
 417                                                 $accum .= '<comment>' . htmlspecialchars( $inner ) . '</comment>';
 418                                         }
 419                                         continue;
 420                                 }
 421                                 $name = $matches[1];
 422                                 $lowerName = strtolower( $name );
 423                                 $attrStart = $i + strlen( $name ) + 1;
 424
 425                                 // Find end of tag
 426                                 $tagEndPos = $noMoreGT ? false : strpos( $text, '>', $attrStart );
 427                                 if ( $tagEndPos === false ) {
 428                                         // Infinite backtrack
 429                                         // Disable tag search to prevent worst-case O(N^2) performance
 430                                         $noMoreGT = true;
 431                                         $accum .= '&lt;';
 432                                         ++$i;
 433                                         continue;
 434                                 }
 435
 436                                 // Handle ignored tags
 437                                 if ( in_array( $lowerName, $ignoredTags ) ) {
 438                                         $accum .= '<ignore>' . htmlspecialchars( substr( $text, $i, $tagEndPos - $i + 1 ) ) . '</ignore>';
 439                                         $i = $tagEndPos + 1;
 440                                         continue;
 441                                 }
 442
 443                                 $tagStartPos = $i;
 444                                 if ( $text[$tagEndPos-1] == '/' ) {
 445                                         $attrEnd = $tagEndPos - 1;
 446                                         $inner = null;
 447                                         $i = $tagEndPos + 1;
 448                                         $close = '';
 449                                 } else {
 450                                         $attrEnd = $tagEndPos;
 451                                         // Find closing tag
 452                                         if ( preg_match( "/<\/" . preg_quote( $name, '/' ) . "\s*>/i",
 453                                                         $text, $matches, PREG_OFFSET_CAPTURE, $tagEndPos + 1 ) )
 454                                         {
 455                                                 $inner = substr( $text, $tagEndPos + 1, $matches[0][1] - $tagEndPos - 1 );
 456                                                 $i = $matches[0][1] + strlen( $matches[0][0] );
 457                                                 $close = '<close>' . htmlspecialchars( $matches[0][0] ) . '</close>';
 458                                         } else {
 459                                                 // No end tag -- let it run out to the end of the text.
 460                                                 $inner = substr( $text, $tagEndPos + 1 );
 461                                                 $i = $lengthText;
 462                                                 $close = '';
 463                                         }
 464                                 }
 465                                 // <includeonly> and <noinclude> just become <ignore> tags
 466                                 if ( in_array( $lowerName, $ignoredElements ) ) {
 467                                         $accum .= '<ignore>' . htmlspecialchars( substr( $text, $tagStartPos, $i - $tagStartPos ) )
 468                                                 . '</ignore>';
 469                                         continue;
 470                                 }
 471
 472                                 $accum .= '<ext>';
 473                                 if ( $attrEnd <= $attrStart ) {
 474                                         $attr = '';
 475                                 } else {
 476                                         $attr = substr( $text, $attrStart, $attrEnd - $attrStart );
 477                                 }
 478                                 $accum .= '<name>' . htmlspecialchars( $name ) . '</name>' .
 479                                         // Note that the attr element contains the whitespace between name and attribute,
 480                                         // this is necessary for precise reconstruction during pre-save transform.
 481                                         '<attr>' . htmlspecialchars( $attr ) . '</attr>';
 482                                 if ( $inner !== null ) {
 483                                         $accum .= '<inner>' . htmlspecialchars( $inner ) . '</inner>';
 484                                 }
 485                                 $accum .= $close . '</ext>';
 486                         } elseif ( $found == 'line-start' ) {
 487                                 // Is this the start of a heading?
 488                                 // Line break belongs before the heading element in any case
 489                                 if ( $fakeLineStart ) {
 490                                         $fakeLineStart = false;
 491                                 } else {
 492                                         $accum .= $curChar;
 493                                         $i++;
 494                                 }
 495
 496                                 $count = strspn( $text, '=', $i, 6 );
 497                                 if ( $count == 1 && $findEquals ) {
 498                                         // DWIM: This looks kind of like a name/value separator
 499                                         // Let's let the equals handler have it and break the potential heading
 500                                         // This is heuristic, but AFAICT the methods for completely correct disambiguation are very complex.
 501                                 } elseif ( $count > 0 ) {
 502                                         $piece = array(
 503                                                 'open' => "\n",
 504                                                 'close' => "\n",
 505                                                 'parts' => array( new PPDPart( str_repeat( '=', $count ) ) ),
 506                                                 'startPos' => $i,
 507                                                 'count' => $count );
 508                                         $stack->push( $piece );
 509                                         $accum =& $stack->getAccum();
 510                                         $flags = $stack->getFlags();
 511                                         extract( $flags );
 512                                         $i += $count;
 513                                 }
 514                         } elseif ( $found == 'line-end' ) {
 515                                 $piece = $stack->top;
 516                                 // A heading must be open, otherwise \n wouldn't have been in the search list
 517                                 assert( '$piece->open == "\n"' );
 518                                 $part = $piece->getCurrentPart();
 519                                 // Search back through the input to see if it has a proper close
 520                                 // Do this using the reversed string since the other solutions (end anchor, etc.) are inefficient
 521                                 $wsLength = strspn( $revText, " \t", $lengthText - $i );
 522                                 $searchStart = $i - $wsLength;
 523                                 if ( isset( $part->commentEnd ) && $searchStart - 1 == $part->commentEnd ) {
 524                                         // Comment found at line end
 525                                         // Search for equals signs before the comment
 526                                         $searchStart = $part->visualEnd;
 527                                         $searchStart -= strspn( $revText, " \t", $lengthText - $searchStart );
 528                                 }
 529                                 $count = $piece->count;
 530                                 $equalsLength = strspn( $revText, '=', $lengthText - $searchStart );
 531                                 if ( $equalsLength > 0 ) {
 532                                         if ( $searchStart - $equalsLength == $piece->startPos ) {
 533                                                 // This is just a single string of equals signs on its own line
 534                                                 // Replicate the doHeadings behavior /={count}(.+)={count}/
 535                                                 // First find out how many equals signs there really are (don't stop at 6)
 536                                                 $count = $equalsLength;
 537                                                 if ( $count < 3 ) {
 538                                                         $count = 0;
 539                                                 } else {
 540                                                         $count = min( 6, intval( ( $count - 1 ) / 2 ) );
 541                                                 }
 542                                         } else {
 543                                                 $count = min( $equalsLength, $count );
 544                                         }
 545                                         if ( $count > 0 ) {
 546                                                 // Normal match, output <h>
 547                                                 $element = "<h level=\"$count\" i=\"$headingIndex\">$accum</h>";
 548                                                 $headingIndex++;
 549                                         } else {
 550                                                 // Single equals sign on its own line, count=0
 551                                                 $element = $accum;
 552                                         }
 553                                 } else {
 554                                         // No match, no <h>, just pass down the inner text
 555                                         $element = $accum;
 556                                 }
 557                                 // Unwind the stack
 558                                 $stack->pop();
 559                                 $accum =& $stack->getAccum();
 560                                 $flags = $stack->getFlags();
 561                                 extract( $flags );
 562
 563                                 // Append the result to the enclosing accumulator
 564                                 $accum .= $element;
 565                                 // Note that we do NOT increment the input pointer.
 566                                 // This is because the closing linebreak could be the opening linebreak of
 567                                 // another heading. Infinite loops are avoided because the next iteration MUST
 568                                 // hit the heading open case above, which unconditionally increments the
 569                                 // input pointer.
 570                         } elseif ( $found == 'open' ) {
 571                                 # count opening brace characters
 572                                 $count = strspn( $text, $curChar, $i );
 573
 574                                 # we need to add to stack only if opening brace count is enough for one of the rules
 575                                 if ( $count >= $rule['min'] ) {
 576                                         # Add it to the stack
 577                                         $piece = array(
 578                                                 'open' => $curChar,
 579                                                 'close' => $rule['end'],
 580                                                 'count' => $count,
 581                                                 'lineStart' => ($i > 0 && $text[$i-1] == "\n"),
 582                                         );
 583
 584                                         $stack->push( $piece );
 585                                         $accum =& $stack->getAccum();
 586                                         $flags = $stack->getFlags();
 587                                         extract( $flags );
 588                                 } else {
 589                                         # Add literal brace(s)
 590                                         $accum .= htmlspecialchars( str_repeat( $curChar, $count ) );
 591                                 }
 592                                 $i += $count;
 593                         } elseif ( $found == 'close' ) {
 594                                 $piece = $stack->top;
 595                                 # lets check if there are enough characters for closing brace
 596                                 $maxCount = $piece->count;
 597                                 $count = strspn( $text, $curChar, $i, $maxCount );
 598
 599                                 # check for maximum matching characters (if there are 5 closing
 600                                 # characters, we will probably need only 3 - depending on the rules)
 601                                 $rule = $rules[$piece->open];
 602                                 if ( $count > $rule['max'] ) {
 603                                         # The specified maximum exists in the callback array, unless the caller
 604                                         # has made an error
 605                                         $matchingCount = $rule['max'];
 606                                 } else {
 607                                         # Count is less than the maximum
 608                                         # Skip any gaps in the callback array to find the true largest match
 609                                         # Need to use array_key_exists not isset because the callback can be null
 610                                         $matchingCount = $count;
 611                                         while ( $matchingCount > 0 && !array_key_exists( $matchingCount, $rule['names'] ) ) {
 612                                                 --$matchingCount;
 613                                         }
 614                                 }
 615
 616                                 if ( $matchingCount <= 0 ) {
 617                                         # No matching element found in callback array
 618                                         # Output a literal closing brace and continue
 619                                         $accum .= htmlspecialchars( str_repeat( $curChar, $count ) );
 620                                         $i += $count;
 621                                         continue;
 622                                 }
 623                                 $name = $rule['names'][$matchingCount];
 624                                 if ( $name === null ) {
 625                                         // No element, just literal text
 626                                         $element = $piece->breakSyntax( $matchingCount ) . str_repeat( $rule['end'], $matchingCount );
 627                                 } else {
 628                                         # Create XML element
 629                                         # Note: $parts is already XML, does not need to be encoded further
 630                                         $parts = $piece->parts;
 631                                         $title = $parts[0]->out;
 632                                         unset( $parts[0] );
 633
 634                                         # The invocation is at the start of the line if lineStart is set in
 635                                         # the stack, and all opening brackets are used up.
 636                                         if ( $maxCount == $matchingCount && !empty( $piece->lineStart ) ) {
 637                                                 $attr = ' lineStart="1"';
 638                                         } else {
 639                                                 $attr = '';
 640                                         }
 641
 642                                         $element = "<$name$attr>";
 643                                         $element .= "<title>$title</title>";
 644                                         $argIndex = 1;
 645                                         foreach ( $parts as $part ) {
 646                                                 if ( isset( $part->eqpos ) ) {
 647                                                         $argName = substr( $part->out, 0, $part->eqpos );
 648                                                         $argValue = substr( $part->out, $part->eqpos + 1 );
 649                                                         $element .= "<part><name>$argName</name>=<value>$argValue</value></part>";
 650                                                 } else {
 651                                                         $element .= "<part><name index=\"$argIndex\" /><value>{$part->out}</value></part>";
 652                                                         $argIndex++;
 653                                                 }
 654                                         }
 655                                         $element .= "</$name>";
 656                                 }
 657
 658                                 # Advance input pointer
 659                                 $i += $matchingCount;
 660
 661                                 # Unwind the stack
 662                                 $stack->pop();
 663                                 $accum =& $stack->getAccum();
 664
 665                                 # Re-add the old stack element if it still has unmatched opening characters remaining
 666                                 if ( $matchingCount < $piece->count ) {
 667                                         $piece->parts = array( new PPDPart );
 668                                         $piece->count -= $matchingCount;
 669                                         # do we still qualify for any callback with remaining count?
 670                                         $min = $rules[$piece->open]['min'];
 671                                         if ( $piece->count >= $min ) {
 672                                                 $stack->push( $piece );
 673                                                 $accum =& $stack->getAccum();
 674                                         } else {
 675                                                 $accum .= str_repeat( $piece->open, $piece->count );
 676                                         }
 677                                 }
 678                                 $flags = $stack->getFlags();
 679                                 extract( $flags );
 680
 681                                 # Add XML element to the enclosing accumulator
 682                                 $accum .= $element;
 683                         } elseif ( $found == 'pipe' ) {
 684                                 $findEquals = true; // shortcut for getFlags()
 685                                 $stack->addPart();
 686                                 $accum =& $stack->getAccum();
 687                                 ++$i;
 688                         } elseif ( $found == 'equals' ) {
 689                                 $findEquals = false; // shortcut for getFlags()
 690                                 $stack->getCurrentPart()->eqpos = strlen( $accum );
 691                                 $accum .= '=';
 692                                 ++$i;
 693                         }
 694                 }
 695
 696                 # Output any remaining unclosed brackets
 697                 foreach ( $stack->stack as $piece ) {
 698                         $stack->rootAccum .= $piece->breakSyntax();
 699                 }
 700                 $stack->rootAccum .= '</root>';
 701                 $xml = $stack->rootAccum;
 702
 703                 wfProfileOut( __METHOD__ );
 704
 705                 return $xml;
 706         }
 707 }
 708
 709 /**
 710  * Stack class to help Preprocessor::preprocessToObj()
 711  * @ingroup Parser
 712  */
 713 class PPDStack {
 714         var $stack, $rootAccum;
 715
 716         /**
 717          * @var PPDStack
 718          */
 719         var $top;
 720         var $out;
 721         var $elementClass = 'PPDStackElement';
 722
 723         static $false = false;
 724
 725         function __construct() {
 726                 $this->stack = array();
 727                 $this->top = false;
 728                 $this->rootAccum = '';
 729                 $this->accum =& $this->rootAccum;
 730         }
 731
 732         /**
 733          * @return int
 734          */
 735         function count() {
 736                 return count( $this->stack );
 737         }
 738
 739         function &getAccum() {
 740                 return $this->accum;
 741         }
 742
 743         function getCurrentPart() {
 744                 if ( $this->top === false ) {
 745                         return false;
 746                 } else {
 747                         return $this->top->getCurrentPart();
 748                 }
 749         }
 750
 751         function push( $data ) {
 752                 if ( $data instanceof $this->elementClass ) {
 753                         $this->stack[] = $data;
 754                 } else {
 755                         $class = $this->elementClass;
 756                         $this->stack[] = new $class( $data );
 757                 }
 758                 $this->top = $this->stack[count( $this->stack ) - 1];
 759                 $this->accum =& $this->top->getAccum();
 760         }
 761
 762         function pop() {
 763                 if ( !count( $this->stack ) ) {
 764                         throw new MWException( __METHOD__ . ': no elements remaining' );
 765                 }
 766                 $temp = array_pop( $this->stack );
 767
 768                 if ( count( $this->stack ) ) {
 769                         $this->top = $this->stack[count( $this->stack ) - 1];
 770                         $this->accum =& $this->top->getAccum();
 771                 } else {
 772                         $this->top = self::$false;
 773                         $this->accum =& $this->rootAccum;
 774                 }
 775                 return $temp;
 776         }
 777
 778         function addPart( $s = '' ) {
 779                 $this->top->addPart( $s );
 780                 $this->accum =& $this->top->getAccum();
 781         }
 782
 783         /**
 784          * @return array
 785          */
 786         function getFlags() {
 787                 if ( !count( $this->stack ) ) {
 788                         return array(
 789                                 'findEquals' => false,
 790                                 'findPipe' => false,
 791                                 'inHeading' => false,
 792                         );
 793                 } else {
 794                         return $this->top->getFlags();
 795                 }
 796         }
 797 }
 798
 799 /**
 800  * @ingroup Parser
 801  */
 802 class PPDStackElement {
 803         var     $open,              // Opening character (\n for heading)
 804                 $close,             // Matching closing character
 805                 $count,             // Number of opening characters found (number of "=" for heading)
 806                 $parts,             // Array of PPDPart objects describing pipe-separated parts.
 807                 $lineStart;         // True if the open char appeared at the start of the input line. Not set for headings.
 808
 809         var $partClass = 'PPDPart';
 810
 811         function __construct( $data = array() ) {
 812                 $class = $this->partClass;
 813                 $this->parts = array( new $class );
 814
 815                 foreach ( $data as $name => $value ) {
 816                         $this->$name = $value;
 817                 }
 818         }
 819
 820         function &getAccum() {
 821                 return $this->parts[count( $this->parts ) - 1]->out;
 822         }
 823
 824         function addPart( $s = '' ) {
 825                 $class = $this->partClass;
 826                 $this->parts[] = new $class( $s );
 827         }
 828
 829         function getCurrentPart() {
 830                 return $this->parts[count( $this->parts ) - 1];
 831         }
 832
 833         /**
 834          * @return array
 835          */
 836         function getFlags() {
 837                 $partCount = count( $this->parts );
 838                 $findPipe = $this->open != "\n" && $this->open != '[';
 839                 return array(
 840                         'findPipe' => $findPipe,
 841                         'findEquals' => $findPipe && $partCount > 1 && !isset( $this->parts[$partCount - 1]->eqpos ),
 842                         'inHeading' => $this->open == "\n",
 843                 );
 844         }
 845
 846         /**
 847          * Get the output string that would result if the close is not found.
 848          *
 849          * @return string
 850          */
 851         function breakSyntax( $openingCount = false ) {
 852                 if ( $this->open == "\n" ) {
 853                         $s = $this->parts[0]->out;
 854                 } else {
 855                         if ( $openingCount === false ) {
 856                                 $openingCount = $this->count;
 857                         }
 858                         $s = str_repeat( $this->open, $openingCount );
 859                         $first = true;
 860                         foreach ( $this->parts as $part ) {
 861                                 if ( $first ) {
 862                                         $first = false;
 863                                 } else {
 864                                         $s .= '|';
 865                                 }
 866                                 $s .= $part->out;
 867                         }
 868                 }
 869                 return $s;
 870         }
 871 }
 872
 873 /**
 874  * @ingroup Parser
 875  */
 876 class PPDPart {
 877         var $out; // Output accumulator string
 878
 879         // Optional member variables:
 880         //   eqpos        Position of equals sign in output accumulator
 881         //   commentEnd   Past-the-end input pointer for the last comment encountered
 882         //   visualEnd    Past-the-end input pointer for the end of the accumulator minus comments
 883
 884         function __construct( $out = '' ) {
 885                 $this->out = $out;
 886         }
 887 }
 888
 889 /**
 890  * An expansion frame, used as a context to expand the result of preprocessToObj()
 891  * @ingroup Parser
 892  */
 893 class PPFrame_DOM implements PPFrame {
 894
 895         /**
 896          * @var Preprocessor
 897          */
 898         var $preprocessor;
 899
 900         /**
 901          * @var Parser
 902          */
 903         var $parser;
 904
 905         /**
 906          * @var Title
 907          */
 908         var $title;
 909         var $titleCache;
 910
 911         /**
 912          * Hashtable listing templates which are disallowed for expansion in this frame,
 913          * having been encountered previously in parent frames.
 914          */
 915         var $loopCheckHash;
 916
 917         /**
 918          * Recursion depth of this frame, top = 0
 919          * Note that this is NOT the same as expansion depth in expand()
 920          */
 921         var $depth;
 922
 923         /**
 924          * Construct a new preprocessor frame.
 925          * @param $preprocessor Preprocessor The parent preprocessor
 926          */
 927         function __construct( $preprocessor ) {
 928                 $this->preprocessor = $preprocessor;
 929                 $this->parser = $preprocessor->parser;
 930                 $this->title = $this->parser->mTitle;
 931                 $this->titleCache = array( $this->title ? $this->title->getPrefixedDBkey() : false );
 932                 $this->loopCheckHash = array();
 933                 $this->depth = 0;
 934         }
 935
 936         /**
 937          * Create a new child frame
 938          * $args is optionally a multi-root PPNode or array containing the template arguments
 939          *
 940          * @return PPTemplateFrame_DOM
 941          */
 942         function newChild( $args = false, $title = false, $indexOffset = 0 ) {
 943                 $namedArgs = array();
 944                 $numberedArgs = array();
 945                 if ( $title === false ) {
 946                         $title = $this->title;
 947                 }
 948                 if ( $args !== false ) {
 949                         $xpath = false;
 950                         if ( $args instanceof PPNode ) {
 951                                 $args = $args->node;
 952                         }
 953                         foreach ( $args as $arg ) {
 954                                 if ( $arg instanceof PPNode ) {
 955                                         $arg = $arg->node;
 956                                 }
 957                                 if ( !$xpath ) {
 958                                         $xpath = new DOMXPath( $arg->ownerDocument );
 959                                 }
 960
 961                                 $nameNodes = $xpath->query( 'name', $arg );
 962                                 $value = $xpath->query( 'value', $arg );
 963                                 if ( $nameNodes->item( 0 )->hasAttributes() ) {
 964                                         // Numbered parameter
 965                                         $index = $nameNodes->item( 0 )->attributes->getNamedItem( 'index' )->textContent;
 966                                         $index = $index - $indexOffset;
 967                                         $numberedArgs[$index] = $value->item( 0 );
 968                                         unset( $namedArgs[$index] );
 969                                 } else {
 970                                         // Named parameter
 971                                         $name = trim( $this->expand( $nameNodes->item( 0 ), PPFrame::STRIP_COMMENTS ) );
 972                                         $namedArgs[$name] = $value->item( 0 );
 973                                         unset( $numberedArgs[$name] );
 974                                 }
 975                         }
 976                 }
 977                 return new PPTemplateFrame_DOM( $this->preprocessor, $this, $numberedArgs, $namedArgs, $title );
 978         }
 979
 980         /**
 981          * @throws MWException
 982          * @param $root
 983          * @param $flags int
 984          * @return string
 985          */
 986         function expand( $root, $flags = 0 ) {
 987                 static $expansionDepth = 0;
 988                 if ( is_string( $root ) ) {
 989                         return $root;
 990                 }
 991
 992                 if ( ++$this->parser->mPPNodeCount > $this->parser->mOptions->getMaxPPNodeCount() ) {
 993                         $this->parser->limitationWarn( 'node-count-exceeded',
 994                                 $this->parser->mPPNodeCount,
 995                                 $this->parser->mOptions->getMaxPPNodeCount()
 996                         );
 997                         return '<span class="error">Node-count limit exceeded</span>';
 998                 }
 999
1000                 if ( $expansionDepth > $this->parser->mOptions->getMaxPPExpandDepth() ) {
1001                         $this->parser->limitationWarn( 'expansion-depth-exceeded',
1002                                 $expansionDepth,
1003                                 $this->parser->mOptions->getMaxPPExpandDepth()
1004                         );
1005                         return '<span class="error">Expansion depth limit exceeded</span>';
1006                 }
1007                 wfProfileIn( __METHOD__ );
1008                 ++$expansionDepth;
1009                 if ( $expansionDepth > $this->parser->mHighestExpansionDepth ) {
1010                         $this->parser->mHighestExpansionDepth = $expansionDepth;
1011                 }
1012
1013                 if ( $root instanceof PPNode_DOM ) {
1014                         $root = $root->node;
1015                 }
1016                 if ( $root instanceof DOMDocument ) {
1017                         $root = $root->documentElement;
1018                 }
1019
1020                 $outStack = array( '', '' );
1021                 $iteratorStack = array( false, $root );
1022                 $indexStack = array( 0, 0 );
1023
1024                 while ( count( $iteratorStack ) > 1 ) {
1025                         $level = count( $outStack ) - 1;
1026                         $iteratorNode =& $iteratorStack[$level];
1027                         $out =& $outStack[$level];
1028                         $index =& $indexStack[$level];
1029
1030                         if ( $iteratorNode instanceof PPNode_DOM ) {
1031                                 $iteratorNode = $iteratorNode->node;
1032                         }
1033
1034                         if ( is_array( $iteratorNode ) ) {
1035                                 if ( $index >= count( $iteratorNode ) ) {
1036                                         // All done with this iterator
1037                                         $iteratorStack[$level] = false;
1038                                         $contextNode = false;
1039                                 } else {
1040                                         $contextNode = $iteratorNode[$index];
1041                                         $index++;
1042                                 }
1043                         } elseif ( $iteratorNode instanceof DOMNodeList ) {
1044                                 if ( $index >= $iteratorNode->length ) {
1045                                         // All done with this iterator
1046                                         $iteratorStack[$level] = false;
1047                                         $contextNode = false;
1048                                 } else {
1049                                         $contextNode = $iteratorNode->item( $index );
1050                                         $index++;
1051                                 }
1052                         } else {
1053                                 // Copy to $contextNode and then delete from iterator stack,
1054                                 // because this is not an iterator but we do have to execute it once
1055                                 $contextNode = $iteratorStack[$level];
1056                                 $iteratorStack[$level] = false;
1057                         }
1058
1059                         if ( $contextNode instanceof PPNode_DOM ) {
1060                                 $contextNode = $contextNode->node;
1061                         }
1062
1063                         $newIterator = false;
1064
1065                         if ( $contextNode === false ) {
1066                                 // nothing to do
1067                         } elseif ( is_string( $contextNode ) ) {
1068                                 $out .= $contextNode;
1069                         } elseif ( is_array( $contextNode ) || $contextNode instanceof DOMNodeList ) {
1070                                 $newIterator = $contextNode;
1071                         } elseif ( $contextNode instanceof DOMNode ) {
1072                                 if ( $contextNode->nodeType == XML_TEXT_NODE ) {
1073                                         $out .= $contextNode->nodeValue;
1074                                 } elseif ( $contextNode->nodeName == 'template' ) {
1075                                         # Double-brace expansion
1076                                         $xpath = new DOMXPath( $contextNode->ownerDocument );
1077                                         $titles = $xpath->query( 'title', $contextNode );
1078                                         $title = $titles->item( 0 );
1079                                         $parts = $xpath->query( 'part', $contextNode );
1080                                         if ( $flags & PPFrame::NO_TEMPLATES ) {
1081                                                 $newIterator = $this->virtualBracketedImplode( '{{', '|', '}}', $title, $parts );
1082                                         } else {
1083                                                 $lineStart = $contextNode->getAttribute( 'lineStart' );
1084                                                 $params = array(
1085                                                         'title' => new PPNode_DOM( $title ),
1086                                                         'parts' => new PPNode_DOM( $parts ),
1087                                                         'lineStart' => $lineStart );
1088                                                 $ret = $this->parser->braceSubstitution( $params, $this );
1089                                                 if ( isset( $ret['object'] ) ) {
1090                                                         $newIterator = $ret['object'];
1091                                                 } else {
1092                                                         $out .= $ret['text'];
1093                                                 }
1094                                         }
1095                                 } elseif ( $contextNode->nodeName == 'tplarg' ) {
1096                                         # Triple-brace expansion
1097                                         $xpath = new DOMXPath( $contextNode->ownerDocument );
1098                                         $titles = $xpath->query( 'title', $contextNode );
1099                                         $title = $titles->item( 0 );
1100                                         $parts = $xpath->query( 'part', $contextNode );
1101                                         if ( $flags & PPFrame::NO_ARGS ) {
1102                                                 $newIterator = $this->virtualBracketedImplode( '{{{', '|', '}}}', $title, $parts );
1103                                         } else {
1104                                                 $params = array(
1105                                                         'title' => new PPNode_DOM( $title ),
1106                                                         'parts' => new PPNode_DOM( $parts ) );
1107                                                 $ret = $this->parser->argSubstitution( $params, $this );
1108                                                 if ( isset( $ret['object'] ) ) {
1109                                                         $newIterator = $ret['object'];
1110                                                 } else {
1111                                                         $out .= $ret['text'];
1112                                                 }
1113                                         }
1114                                 } elseif ( $contextNode->nodeName == 'comment' ) {
1115                                         # HTML-style comment
1116                                         # Remove it in HTML, pre+remove and STRIP_COMMENTS modes
1117                                         if ( $this->parser->ot['html']
1118                                                 || ( $this->parser->ot['pre'] && $this->parser->mOptions->getRemoveComments() )
1119                                                 || ( $flags & PPFrame::STRIP_COMMENTS ) )
1120                                         {
1121                                                 $out .= '';
1122                                         }
1123                                         # Add a strip marker in PST mode so that pstPass2() can run some old-fashioned regexes on the result
1124                                         # Not in RECOVER_COMMENTS mode (extractSections) though
1125                                         elseif ( $this->parser->ot['wiki'] && !( $flags & PPFrame::RECOVER_COMMENTS ) ) {
1126                                                 $out .= $this->parser->insertStripItem( $contextNode->textContent );
1127                                         }
1128                                         # Recover the literal comment in RECOVER_COMMENTS and pre+no-remove
1129                                         else {
1130                                                 $out .= $contextNode->textContent;
1131                                         }
1132                                 } elseif ( $contextNode->nodeName == 'ignore' ) {
1133                                         # Output suppression used by <includeonly> etc.
1134                                         # OT_WIKI will only respect <ignore> in substed templates.
1135                                         # The other output types respect it unless NO_IGNORE is set.
1136                                         # extractSections() sets NO_IGNORE and so never respects it.
1137                                         if ( ( !isset( $this->parent ) && $this->parser->ot['wiki'] ) || ( $flags & PPFrame::NO_IGNORE ) ) {
1138                                                 $out .= $contextNode->textContent;
1139                                         } else {
1140                                                 $out .= '';
1141                                         }
1142                                 } elseif ( $contextNode->nodeName == 'ext' ) {
1143                                         # Extension tag
1144                                         $xpath = new DOMXPath( $contextNode->ownerDocument );
1145                                         $names = $xpath->query( 'name', $contextNode );
1146                                         $attrs = $xpath->query( 'attr', $contextNode );
1147                                         $inners = $xpath->query( 'inner', $contextNode );
1148                                         $closes = $xpath->query( 'close', $contextNode );
1149                                         $params = array(
1150                                                 'name' => new PPNode_DOM( $names->item( 0 ) ),
1151                                                 'attr' => $attrs->length > 0 ? new PPNode_DOM( $attrs->item( 0 ) ) : null,
1152                                                 'inner' => $inners->length > 0 ? new PPNode_DOM( $inners->item( 0 ) ) : null,
1153                                                 'close' => $closes->length > 0 ? new PPNode_DOM( $closes->item( 0 ) ) : null,
1154                                         );
1155                                         $out .= $this->parser->extensionSubstitution( $params, $this );
1156                                 } elseif ( $contextNode->nodeName == 'h' ) {
1157                                         # Heading
1158                                         $s = $this->expand( $contextNode->childNodes, $flags );
1159
1160                                         # Insert a heading marker only for <h> children of <root>
1161                                         # This is to stop extractSections from going over multiple tree levels
1162                                         if ( $contextNode->parentNode->nodeName == 'root' && $this->parser->ot['html'] ) {
1163                                                 # Insert heading index marker
1164                                                 $headingIndex = $contextNode->getAttribute( 'i' );
1165                                                 $titleText = $this->title->getPrefixedDBkey();
1166                                                 $this->parser->mHeadings[] = array( $titleText, $headingIndex );
1167                                                 $serial = count( $this->parser->mHeadings ) - 1;
1168                                                 $marker = "{$this->parser->mUniqPrefix}-h-$serial-" . Parser::MARKER_SUFFIX;
1169                                                 $count = $contextNode->getAttribute( 'level' );
1170                                                 $s = substr( $s, 0, $count ) . $marker . substr( $s, $count );
1171                                                 $this->parser->mStripState->addGeneral( $marker, '' );
1172                                         }
1173                                         $out .= $s;
1174                                 } else {
1175                                         # Generic recursive expansion
1176                                         $newIterator = $contextNode->childNodes;
1177                                 }
1178                         } else {
1179                                 wfProfileOut( __METHOD__ );
1180                                 throw new MWException( __METHOD__ . ': Invalid parameter type' );
1181                         }
1182
1183                         if ( $newIterator !== false ) {
1184                                 if ( $newIterator instanceof PPNode_DOM ) {
1185                                         $newIterator = $newIterator->node;
1186                                 }
1187                                 $outStack[] = '';
1188                                 $iteratorStack[] = $newIterator;
1189                                 $indexStack[] = 0;
1190                         } elseif ( $iteratorStack[$level] === false ) {
1191                                 // Return accumulated value to parent
1192                                 // With tail recursion
1193                                 while ( $iteratorStack[$level] === false && $level > 0 ) {
1194                                         $outStack[$level - 1] .= $out;
1195                                         array_pop( $outStack );
1196                                         array_pop( $iteratorStack );
1197                                         array_pop( $indexStack );
1198                                         $level--;
1199                                 }
1200                         }
1201                 }
1202                 --$expansionDepth;
1203                 wfProfileOut( __METHOD__ );
1204                 return $outStack[0];
1205         }
1206
1207         /**
1208          * @param $sep
1209          * @param $flags
1210          * @return string
1211          */
1212         function implodeWithFlags( $sep, $flags /*, ... */ ) {
1213                 $args = array_slice( func_get_args(), 2 );
1214
1215                 $first = true;
1216                 $s = '';
1217                 foreach ( $args as $root ) {
1218                         if ( $root instanceof PPNode_DOM ) $root = $root->node;
1219                         if ( !is_array( $root ) && !( $root instanceof DOMNodeList ) ) {
1220                                 $root = array( $root );
1221                         }
1222                         foreach ( $root as $node ) {
1223                                 if ( $first ) {
1224                                         $first = false;
1225                                 } else {
1226                                         $s .= $sep;
1227                                 }
1228                                 $s .= $this->expand( $node, $flags );
1229                         }
1230                 }
1231                 return $s;
1232         }
1233
1234         /**
1235          * Implode with no flags specified
1236          * This previously called implodeWithFlags but has now been inlined to reduce stack depth
1237          *
1238          * @return string
1239          */
1240         function implode( $sep /*, ... */ ) {
1241                 $args = array_slice( func_get_args(), 1 );
1242
1243                 $first = true;
1244                 $s = '';
1245                 foreach ( $args as $root ) {
1246                         if ( $root instanceof PPNode_DOM ) {
1247                                 $root = $root->node;
1248                         }
1249                         if ( !is_array( $root ) && !( $root instanceof DOMNodeList ) ) {
1250                                 $root = array( $root );
1251                         }
1252                         foreach ( $root as $node ) {
1253                                 if ( $first ) {
1254                                         $first = false;
1255                                 } else {
1256                                         $s .= $sep;
1257                                 }
1258                                 $s .= $this->expand( $node );
1259                         }
1260                 }
1261                 return $s;
1262         }
1263
1264         /**
1265          * Makes an object that, when expand()ed, will be the same as one obtained
1266          * with implode()
1267          *
1268          * @return array
1269          */
1270         function virtualImplode( $sep /*, ... */ ) {
1271                 $args = array_slice( func_get_args(), 1 );
1272                 $out = array();
1273                 $first = true;
1274
1275                 foreach ( $args as $root ) {
1276                         if ( $root instanceof PPNode_DOM ) {
1277                                 $root = $root->node;
1278                         }
1279                         if ( !is_array( $root ) && !( $root instanceof DOMNodeList ) ) {
1280                                 $root = array( $root );
1281                         }
1282                         foreach ( $root as $node ) {
1283                                 if ( $first ) {
1284                                         $first = false;
1285                                 } else {
1286                                         $out[] = $sep;
1287                                 }
1288                                 $out[] = $node;
1289                         }
1290                 }
1291                 return $out;
1292         }
1293
1294         /**
1295          * Virtual implode with brackets
1296          * @return array
1297          */
1298         function virtualBracketedImplode( $start, $sep, $end /*, ... */ ) {
1299                 $args = array_slice( func_get_args(), 3 );
1300                 $out = array( $start );
1301                 $first = true;
1302
1303                 foreach ( $args as $root ) {
1304                         if ( $root instanceof PPNode_DOM ) {
1305                                 $root = $root->node;
1306                         }
1307                         if ( !is_array( $root ) && !( $root instanceof DOMNodeList ) ) {
1308                                 $root = array( $root );
1309                         }
1310                         foreach ( $root as $node ) {
1311                                 if ( $first ) {
1312                                         $first = false;
1313                                 } else {
1314                                         $out[] = $sep;
1315                                 }
1316                                 $out[] = $node;
1317                         }
1318                 }
1319                 $out[] = $end;
1320                 return $out;
1321         }
1322
1323         function __toString() {
1324                 return 'frame{}';
1325         }
1326
1327         function getPDBK( $level = false ) {
1328                 if ( $level === false ) {
1329                         return $this->title->getPrefixedDBkey();
1330                 } else {
1331                         return isset( $this->titleCache[$level] ) ? $this->titleCache[$level] : false;
1332                 }
1333         }
1334
1335         /**
1336          * @return array
1337          */
1338         function getArguments() {
1339                 return array();
1340         }
1341
1342         /**
1343          * @return array
1344          */
1345         function getNumberedArguments() {
1346                 return array();
1347         }
1348
1349         /**
1350          * @return array
1351          */
1352         function getNamedArguments() {
1353                 return array();
1354         }
1355
1356         /**
1357          * Returns true if there are no arguments in this frame
1358          *
1359          * @return bool
1360          */
1361         function isEmpty() {
1362                 return true;
1363         }
1364
1365         function getArgument( $name ) {
1366                 return false;
1367         }
1368
1369         /**
1370          * Returns true if the infinite loop check is OK, false if a loop is detected
1371          *
1372          * @return bool
1373          */
1374         function loopCheck( $title ) {
1375                 return !isset( $this->loopCheckHash[$title->getPrefixedDBkey()] );
1376         }
1377
1378         /**
1379          * Return true if the frame is a template frame
1380          *
1381          * @return bool
1382          */
1383         function isTemplate() {
1384                 return false;
1385         }
1386
1387         /**
1388          * Get a title of frame
1389          *
1390          * @return Title
1391          */
1392         function getTitle() {
1393                 return $this->title;
1394         }
1395 }
1396
1397 /**
1398  * Expansion frame with template arguments
1399  * @ingroup Parser
1400  */
1401 class PPTemplateFrame_DOM extends PPFrame_DOM {
1402         var $numberedArgs, $namedArgs;
1403
1404         /**
1405          * @var PPFrame_DOM
1406          */
1407         var $parent;
1408         var $numberedExpansionCache, $namedExpansionCache;
1409
1410         /**
1411          * @param $preprocessor
1412          * @param $parent PPFrame_DOM
1413          * @param $numberedArgs array
1414          * @param $namedArgs array
1415          * @param $title Title
1416          */
1417         function __construct( $preprocessor, $parent = false, $numberedArgs = array(), $namedArgs = array(), $title = false ) {
1418                 parent::__construct( $preprocessor );
1419
1420                 $this->parent = $parent;
1421                 $this->numberedArgs = $numberedArgs;
1422                 $this->namedArgs = $namedArgs;
1423                 $this->title = $title;
1424                 $pdbk = $title ? $title->getPrefixedDBkey() : false;
1425                 $this->titleCache = $parent->titleCache;
1426                 $this->titleCache[] = $pdbk;
1427                 $this->loopCheckHash = /*clone*/ $parent->loopCheckHash;
1428                 if ( $pdbk !== false ) {
1429                         $this->loopCheckHash[$pdbk] = true;
1430                 }
1431                 $this->depth = $parent->depth + 1;
1432                 $this->numberedExpansionCache = $this->namedExpansionCache = array();
1433         }
1434
1435         function __toString() {
1436                 $s = 'tplframe{';
1437                 $first = true;
1438                 $args = $this->numberedArgs + $this->namedArgs;
1439                 foreach ( $args as $name => $value ) {
1440                         if ( $first ) {
1441                                 $first = false;
1442                         } else {
1443                                 $s .= ', ';
1444                         }
1445                         $s .= "\"$name\":\"" .
1446                                 str_replace( '"', '\\"', $value->ownerDocument->saveXML( $value ) ) . '"';
1447                 }
1448                 $s .= '}';
1449                 return $s;
1450         }
1451
1452         /**
1453          * Returns true if there are no arguments in this frame
1454          *
1455          * @return bool
1456          */
1457         function isEmpty() {
1458                 return !count( $this->numberedArgs ) && !count( $this->namedArgs );
1459         }
1460
1461         function getArguments() {
1462                 $arguments = array();
1463                 foreach ( array_merge(
1464                                 array_keys( $this->numberedArgs ),
1465                                 array_keys( $this->namedArgs ) ) as $key ) {
1466                         $arguments[$key] = $this->getArgument( $key );
1467                 }
1468                 return $arguments;
1469         }
1470
1471         function getNumberedArguments() {
1472                 $arguments = array();
1473                 foreach ( array_keys( $this->numberedArgs ) as $key ) {
1474                         $arguments[$key] = $this->getArgument( $key );
1475                 }
1476                 return $arguments;
1477         }
1478
1479         function getNamedArguments() {
1480                 $arguments = array();
1481                 foreach ( array_keys( $this->namedArgs ) as $key ) {
1482                         $arguments[$key] = $this->getArgument( $key );
1483                 }
1484                 return $arguments;
1485         }
1486
1487         function getNumberedArgument( $index ) {
1488                 if ( !isset( $this->numberedArgs[$index] ) ) {
1489                         return false;
1490                 }
1491                 if ( !isset( $this->numberedExpansionCache[$index] ) ) {
1492                         # No trimming for unnamed arguments
1493                         $this->numberedExpansionCache[$index] = $this->parent->expand( $this->numberedArgs[$index], PPFrame::STRIP_COMMENTS );
1494                 }
1495                 return $this->numberedExpansionCache[$index];
1496         }
1497
1498         function getNamedArgument( $name ) {
1499                 if ( !isset( $this->namedArgs[$name] ) ) {
1500                         return false;
1501                 }
1502                 if ( !isset( $this->namedExpansionCache[$name] ) ) {
1503                         # Trim named arguments post-expand, for backwards compatibility
1504                         $this->namedExpansionCache[$name] = trim(
1505                                 $this->parent->expand( $this->namedArgs[$name], PPFrame::STRIP_COMMENTS ) );
1506                 }
1507                 return $this->namedExpansionCache[$name];
1508         }
1509
1510         function getArgument( $name ) {
1511                 $text = $this->getNumberedArgument( $name );
1512                 if ( $text === false ) {
1513                         $text = $this->getNamedArgument( $name );
1514                 }
1515                 return $text;
1516         }
1517
1518         /**
1519          * Return true if the frame is a template frame
1520          *
1521          * @return bool
1522          */
1523         function isTemplate() {
1524                 return true;
1525         }
1526 }
1527
1528 /**
1529  * Expansion frame with custom arguments
1530  * @ingroup Parser
1531  */
1532 class PPCustomFrame_DOM extends PPFrame_DOM {
1533         var $args;
1534
1535         function __construct( $preprocessor, $args ) {
1536                 parent::__construct( $preprocessor );
1537                 $this->args = $args;
1538         }
1539
1540         function __toString() {
1541                 $s = 'cstmframe{';
1542                 $first = true;
1543                 foreach ( $this->args as $name => $value ) {
1544                         if ( $first ) {
1545                                 $first = false;
1546                         } else {
1547                                 $s .= ', ';
1548                         }
1549                         $s .= "\"$name\":\"" .
1550                                 str_replace( '"', '\\"', $value->__toString() ) . '"';
1551                 }
1552                 $s .= '}';
1553                 return $s;
1554         }
1555
1556         /**
1557          * @return bool
1558          */
1559         function isEmpty() {
1560                 return !count( $this->args );
1561         }
1562
1563         function getArgument( $index ) {
1564                 if ( !isset( $this->args[$index] ) ) {
1565                         return false;
1566                 }
1567                 return $this->args[$index];
1568         }
1569
1570         function getArguments() {
1571                 return $this->args;
1572         }
1573 }
1574
1575 /**
1576  * @ingroup Parser
1577  */
1578 class PPNode_DOM implements PPNode {
1579
1580         /**
1581          * @var DOMElement
1582          */
1583         var $node;
1584         var $xpath;
1585
1586         function __construct( $node, $xpath = false ) {
1587                 $this->node = $node;
1588         }
1589
1590         /**
1591          * @return DOMXPath
1592          */
1593         function getXPath() {
1594                 if ( $this->xpath === null ) {
1595                         $this->xpath = new DOMXPath( $this->node->ownerDocument );
1596                 }
1597                 return $this->xpath;
1598         }
1599
1600         function __toString() {
1601                 if ( $this->node instanceof DOMNodeList ) {
1602                         $s = '';
1603                         foreach ( $this->node as $node ) {
1604                                 $s .= $node->ownerDocument->saveXML( $node );
1605                         }
1606                 } else {
1607                         $s = $this->node->ownerDocument->saveXML( $this->node );
1608                 }
1609                 return $s;
1610         }
1611
1612         /**
1613          * @return bool|PPNode_DOM
1614          */
1615         function getChildren() {
1616                 return $this->node->childNodes ? new self( $this->node->childNodes ) : false;
1617         }
1618
1619         /**
1620          * @return bool|PPNode_DOM
1621          */
1622         function getFirstChild() {
1623                 return $this->node->firstChild ? new self( $this->node->firstChild ) : false;
1624         }
1625
1626         /**
1627          * @return bool|PPNode_DOM
1628          */
1629         function getNextSibling() {
1630                 return $this->node->nextSibling ? new self( $this->node->nextSibling ) : false;
1631         }
1632
1633         /**
1634          * @param $type
1635          *
1636          * @return bool|PPNode_DOM
1637          */
1638         function getChildrenOfType( $type ) {
1639                 return new self( $this->getXPath()->query( $type, $this->node ) );
1640         }
1641
1642         /**
1643          * @return int
1644          */
1645         function getLength() {
1646                 if ( $this->node instanceof DOMNodeList ) {
1647                         return $this->node->length;
1648                 } else {
1649                         return false;
1650                 }
1651         }
1652
1653         /**
1654          * @param $i
1655          * @return bool|PPNode_DOM
1656          */
1657         function item( $i ) {
1658                 $item = $this->node->item( $i );
1659                 return $item ? new self( $item ) : false;
1660         }
1661
1662         /**
1663          * @return string
1664          */
1665         function getName() {
1666                 if ( $this->node instanceof DOMNodeList ) {
1667                         return '#nodelist';
1668                 } else {
1669                         return $this->node->nodeName;
1670                 }
1671         }
1672
1673         /**
1674          * Split a "<part>" node into an associative array containing:
1675          *  - name          PPNode name
1676          *  - index         String index
1677          *  - value         PPNode value
1678          *
1679          * @throws MWException
1680          * @return array
1681          */
1682         function splitArg() {
1683                 $xpath = $this->getXPath();
1684                 $names = $xpath->query( 'name', $this->node );
1685                 $values = $xpath->query( 'value', $this->node );
1686                 if ( !$names->length || !$values->length ) {
1687                         throw new MWException( 'Invalid brace node passed to ' . __METHOD__ );
1688                 }
1689                 $name = $names->item( 0 );
1690                 $index = $name->getAttribute( 'index' );
1691                 return array(
1692                         'name' => new self( $name ),
1693                         'index' => $index,
1694                         'value' => new self( $values->item( 0 ) ) );
1695         }
1696
1697         /**
1698          * Split an "<ext>" node into an associative array containing name, attr, inner and close
1699          * All values in the resulting array are PPNodes. Inner and close are optional.
1700          *
1701          * @throws MWException
1702          * @return array
1703          */
1704         function splitExt() {
1705                 $xpath = $this->getXPath();
1706                 $names = $xpath->query( 'name', $this->node );
1707                 $attrs = $xpath->query( 'attr', $this->node );
1708                 $inners = $xpath->query( 'inner', $this->node );
1709                 $closes = $xpath->query( 'close', $this->node );
1710                 if ( !$names->length || !$attrs->length ) {
1711                         throw new MWException( 'Invalid ext node passed to ' . __METHOD__ );
1712                 }
1713                 $parts = array(
1714                         'name' => new self( $names->item( 0 ) ),
1715                         'attr' => new self( $attrs->item( 0 ) ) );
1716                 if ( $inners->length ) {
1717                         $parts['inner'] = new self( $inners->item( 0 ) );
1718                 }
1719                 if ( $closes->length ) {
1720                         $parts['close'] = new self( $closes->item( 0 ) );
1721                 }
1722                 return $parts;
1723         }
1724
1725         /**
1726          * Split a "<h>" node
1727          * @throws MWException
1728          * @return array
1729          */
1730         function splitHeading() {
1731                 if ( $this->getName() !== 'h' ) {
1732                         throw new MWException( 'Invalid h node passed to ' . __METHOD__ );
1733                 }
1734                 return array(
1735                         'i' => $this->node->getAttribute( 'i' ),
1736                         'level' => $this->node->getAttribute( 'level' ),
1737                         'contents' => $this->getChildren()
1738                 );
1739         }
1740 }