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