includes/media/XMP.php

   1 <?php
   2 /**
   3  * Reader for XMP data containing properties relevant to images.
   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 Media
  22  */
  23
  24 /**
  25  * Class for reading xmp data containing properties relevant to
  26  * images, and spitting out an array that FormatExif accepts.
  27  *
  28  * Note, this is not meant to recognize every possible thing you can
  29  * encode in XMP. It should recognize all the properties we want.
  30  * For example it doesn't have support for structures with multiple
  31  * nesting levels, as none of the properties we're supporting use that
  32  * feature. If it comes across properties it doesn't recognize, it should
  33  * ignore them.
  34  *
  35  * The public methods one would call in this class are
  36  * - parse( $content )
  37  *    Reads in xmp content.
  38  *    Can potentially be called multiple times with partial data each time.
  39  * - parseExtended( $content )
  40  *    Reads XMPExtended blocks (jpeg files only).
  41  * - getResults
  42  *    Outputs a results array.
  43  *
  44  * Note XMP kind of looks like rdf. They are not the same thing - XMP is
  45  * encoded as a specific subset of rdf. This class can read XMP. It cannot
  46  * read rdf.
  47  *
  48  */
  49 class XMPReader {
  50         private $curItem = array(); // array to hold the current element (and previous element, and so on)
  51
  52         private $ancestorStruct = false; // the structure name when processing nested structures.
  53
  54         private $charContent = false; // temporary holder for character data that appears in xmp doc.
  55
  56         private $mode = array(); // stores the state the xmpreader is in (see MODE_FOO constants)
  57
  58         private $results = array(); // array to hold results
  59
  60         private $processingArray = false; // if we're doing a seq or bag.
  61
  62         private $itemLang = false; // used for lang alts only
  63
  64         private $xmlParser;
  65
  66         private $charset = false;
  67
  68         private $extendedXMPOffset = 0;
  69
  70         protected $items;
  71
  72         /**
  73          * These are various mode constants.
  74          * they are used to figure out what to do
  75          * with an element when its encountered.
  76          *
  77          * For example, MODE_IGNORE is used when processing
  78          * a property we're not interested in. So if a new
  79          * element pops up when we're in that mode, we ignore it.
  80          */
  81         const MODE_INITIAL = 0;
  82         const MODE_IGNORE = 1;
  83         const MODE_LI = 2;
  84         const MODE_LI_LANG = 3;
  85         const MODE_QDESC = 4;
  86
  87         // The following MODE constants are also used in the
  88         // $items array to denote what type of property the item is.
  89         const MODE_SIMPLE = 10;
  90         const MODE_STRUCT = 11; // structure (associative array)
  91         const MODE_SEQ = 12; // ordered list
  92         const MODE_BAG = 13; // unordered list
  93         const MODE_LANG = 14;
  94         const MODE_ALT = 15; // non-language alt. Currently not implemented, and not needed atm.
  95         const MODE_BAGSTRUCT = 16; // A BAG of Structs.
  96
  97         const NS_RDF = 'http://www.w3.org/1999/02/22-rdf-syntax-ns#';
  98         const NS_XML = 'http://www.w3.org/XML/1998/namespace';
  99
 100         /**
 101          * Constructor.
 102          *
 103          * Primary job is to initialize the XMLParser
 104          */
 105         function __construct() {
 106
 107                 if ( !function_exists( 'xml_parser_create_ns' ) ) {
 108                         // this should already be checked by this point
 109                         throw new MWException( 'XMP support requires XML Parser' );
 110                 }
 111
 112                 $this->items = XMPInfo::getItems();
 113
 114                 $this->resetXMLParser();
 115         }
 116
 117         /**
 118          * Main use is if a single item has multiple xmp documents describing it.
 119          * For example in jpeg's with extendedXMP
 120          */
 121         private function resetXMLParser() {
 122
 123                 if ( $this->xmlParser ) {
 124                         //is this needed?
 125                         xml_parser_free( $this->xmlParser );
 126                 }
 127
 128                 $this->xmlParser = xml_parser_create_ns( 'UTF-8', ' ' );
 129                 xml_parser_set_option( $this->xmlParser, XML_OPTION_CASE_FOLDING, 0 );
 130                 xml_parser_set_option( $this->xmlParser, XML_OPTION_SKIP_WHITE, 1 );
 131
 132                 xml_set_element_handler( $this->xmlParser,
 133                         array( $this, 'startElement' ),
 134                         array( $this, 'endElement' ) );
 135
 136                 xml_set_character_data_handler( $this->xmlParser, array( $this, 'char' ) );
 137         }
 138
 139         /** Destroy the xml parser
 140          *
 141          * Not sure if this is actually needed.
 142          */
 143         function __destruct() {
 144                 // not sure if this is needed.
 145                 xml_parser_free( $this->xmlParser );
 146         }
 147
 148         /** Get the result array. Do some post-processing before returning
 149          * the array, and transform any metadata that is special-cased.
 150          *
 151          * @return Array array of results as an array of arrays suitable for
 152          *    FormatMetadata::getFormattedData().
 153          */
 154         public function getResults() {
 155                 // xmp-special is for metadata that affects how stuff
 156                 // is extracted. For example xmpNote:HasExtendedXMP.
 157
 158                 // It is also used to handle photoshop:AuthorsPosition
 159                 // which is weird and really part of another property,
 160                 // see 2:85 in IPTC. See also pg 21 of IPTC4XMP standard.
 161                 // The location fields also use it.
 162
 163                 $data = $this->results;
 164
 165                 wfRunHooks( 'XMPGetResults', array( &$data ) );
 166
 167                 if ( isset( $data['xmp-special']['AuthorsPosition'] )
 168                         && is_string( $data['xmp-special']['AuthorsPosition'] )
 169                         && isset( $data['xmp-general']['Artist'][0] )
 170                 ) {
 171                         // Note, if there is more than one creator,
 172                         // this only applies to first. This also will
 173                         // only apply to the dc:Creator prop, not the
 174                         // exif:Artist prop.
 175
 176                         $data['xmp-general']['Artist'][0] =
 177                                 $data['xmp-special']['AuthorsPosition'] . ', '
 178                                 . $data['xmp-general']['Artist'][0];
 179                 }
 180
 181                 // Go through the LocationShown and LocationCreated
 182                 // changing it to the non-hierarchal form used by
 183                 // the other location fields.
 184
 185                 if ( isset( $data['xmp-special']['LocationShown'][0] )
 186                         && is_array( $data['xmp-special']['LocationShown'][0] )
 187                 ) {
 188                         // the is_array is just paranoia. It should always
 189                         // be an array.
 190                         foreach ( $data['xmp-special']['LocationShown'] as $loc ) {
 191                                 if ( !is_array( $loc ) ) {
 192                                         // To avoid copying over the _type meta-fields.
 193                                         continue;
 194                                 }
 195                                 foreach ( $loc as $field => $val ) {
 196                                         $data['xmp-general'][$field . 'Dest'][] = $val;
 197                                 }
 198                         }
 199                 }
 200                 if ( isset( $data['xmp-special']['LocationCreated'][0] )
 201                         && is_array( $data['xmp-special']['LocationCreated'][0] )
 202                 ) {
 203                         // the is_array is just paranoia. It should always
 204                         // be an array.
 205                         foreach ( $data['xmp-special']['LocationCreated'] as $loc ) {
 206                                 if ( !is_array( $loc ) ) {
 207                                         // To avoid copying over the _type meta-fields.
 208                                         continue;
 209                                 }
 210                                 foreach ( $loc as $field => $val ) {
 211                                         $data['xmp-general'][$field . 'Created'][] = $val;
 212                                 }
 213                         }
 214                 }
 215
 216                 // We don't want to return the special values, since they're
 217                 // special and not info to be stored about the file.
 218                 unset( $data['xmp-special'] );
 219
 220                 // Convert GPSAltitude to negative if below sea level.
 221                 if ( isset( $data['xmp-exif']['GPSAltitudeRef'] )
 222                         && isset( $data['xmp-exif']['GPSAltitude'] )
 223                 ) {
 224
 225                         // Must convert to a real before multiplying by -1
 226                         // XMPValidate guarantees there will always be a '/' in this value.
 227                         list( $nom, $denom ) = explode( '/', $data['xmp-exif']['GPSAltitude'] );
 228                         $data['xmp-exif']['GPSAltitude'] = $nom / $denom;
 229
 230                         if ( $data['xmp-exif']['GPSAltitudeRef'] == '1' ) {
 231                                 $data['xmp-exif']['GPSAltitude'] *= -1;
 232                         }
 233                         unset( $data['xmp-exif']['GPSAltitudeRef'] );
 234                 }
 235
 236                 return $data;
 237         }
 238
 239         /**
 240          * Main function to call to parse XMP. Use getResults to
 241          * get results.
 242          *
 243          * Also catches any errors during processing, writes them to
 244          * debug log, blanks result array and returns false.
 245          *
 246          * @param string $content XMP data
 247          * @param $allOfIt Boolean: If this is all the data (true) or if its split up (false). Default true
 248          * @param $reset Boolean: does xml parser need to be reset. Default false
 249          * @throws MWException
 250          * @return Boolean success.
 251          */
 252         public function parse( $content, $allOfIt = true, $reset = false ) {
 253                 if ( $reset ) {
 254                         $this->resetXMLParser();
 255                 }
 256                 try {
 257
 258                         // detect encoding by looking for BOM which is supposed to be in processing instruction.
 259                         // see page 12 of http://www.adobe.com/devnet/xmp/pdfs/XMPSpecificationPart3.pdf
 260                         if ( !$this->charset ) {
 261                                 $bom = array();
 262                                 if ( preg_match( '/\xEF\xBB\xBF|\xFE\xFF|\x00\x00\xFE\xFF|\xFF\xFE\x00\x00|\xFF\xFE/',
 263                                         $content, $bom )
 264                                 ) {
 265                                         switch ( $bom[0] ) {
 266                                                 case "\xFE\xFF":
 267                                                         $this->charset = 'UTF-16BE';
 268                                                         break;
 269                                                 case "\xFF\xFE":
 270                                                         $this->charset = 'UTF-16LE';
 271                                                         break;
 272                                                 case "\x00\x00\xFE\xFF":
 273                                                         $this->charset = 'UTF-32BE';
 274                                                         break;
 275                                                 case "\xFF\xFE\x00\x00":
 276                                                         $this->charset = 'UTF-32LE';
 277                                                         break;
 278                                                 case "\xEF\xBB\xBF":
 279                                                         $this->charset = 'UTF-8';
 280                                                         break;
 281                                                 default:
 282                                                         //this should be impossible to get to
 283                                                         throw new MWException( "Invalid BOM" );
 284                                         }
 285                                 } else {
 286                                         // standard specifically says, if no bom assume utf-8
 287                                         $this->charset = 'UTF-8';
 288                                 }
 289                         }
 290                         if ( $this->charset !== 'UTF-8' ) {
 291                                 //don't convert if already utf-8
 292                                 wfSuppressWarnings();
 293                                 $content = iconv( $this->charset, 'UTF-8//IGNORE', $content );
 294                                 wfRestoreWarnings();
 295                         }
 296
 297                         $ok = xml_parse( $this->xmlParser, $content, $allOfIt );
 298                         if ( !$ok ) {
 299                                 $error = xml_error_string( xml_get_error_code( $this->xmlParser ) );
 300                                 $where = 'line: ' . xml_get_current_line_number( $this->xmlParser )
 301                                         . ' column: ' . xml_get_current_column_number( $this->xmlParser )
 302                                         . ' byte offset: ' . xml_get_current_byte_index( $this->xmlParser );
 303
 304                                 wfDebugLog( 'XMP', "XMPReader::parse : Error reading XMP content: $error ($where)" );
 305                                 $this->results = array(); // blank if error.
 306                                 return false;
 307                         }
 308                 } catch ( MWException $e ) {
 309                         wfDebugLog( 'XMP', 'XMP parse error: ' . $e );
 310                         $this->results = array();
 311
 312                         return false;
 313                 }
 314
 315                 return true;
 316         }
 317
 318         /** Entry point for XMPExtended blocks in jpeg files
 319          *
 320          * @todo In serious need of testing
 321          * @see http://www.adobe.ge/devnet/xmp/pdfs/XMPSpecificationPart3.pdf XMP spec part 3 page 20
 322          * @param string $content XMPExtended block minus the namespace signature
 323          * @return Boolean If it succeeded.
 324          */
 325         public function parseExtended( $content ) {
 326                 // @todo FIXME: This is untested. Hard to find example files
 327                 // or programs that make such files..
 328                 $guid = substr( $content, 0, 32 );
 329                 if ( !isset( $this->results['xmp-special']['HasExtendedXMP'] )
 330                         || $this->results['xmp-special']['HasExtendedXMP'] !== $guid
 331                 ) {
 332                         wfDebugLog( 'XMP', __METHOD__ .
 333                                 " Ignoring XMPExtended block due to wrong guid (guid= '$guid')" );
 334
 335                         return false;
 336                 }
 337                 $len = unpack( 'Nlength/Noffset', substr( $content, 32, 8 ) );
 338
 339                 if ( !$len || $len['length'] < 4 || $len['offset'] < 0 || $len['offset'] > $len['length'] ) {
 340                         wfDebugLog( 'XMP', __METHOD__ . 'Error reading extended XMP block, invalid length or offset.' );
 341
 342                         return false;
 343                 }
 344
 345                 // we're not very robust here. we should accept it in the wrong order.
 346                 // To quote the XMP standard:
 347                 // "A JPEG writer should write the ExtendedXMP marker segments in order,
 348                 // immediately following the StandardXMP. However, the JPEG standard
 349                 // does not require preservation of marker segment order. A robust JPEG
 350                 // reader should tolerate the marker segments in any order."
 351                 //
 352                 // otoh the probability that an image will have more than 128k of
 353                 // metadata is rather low... so the probability that it will have
 354                 // > 128k, and be in the wrong order is very low...
 355
 356                 if ( $len['offset'] !== $this->extendedXMPOffset ) {
 357                         wfDebugLog( 'XMP', __METHOD__ . 'Ignoring XMPExtended block due to wrong order. (Offset was '
 358                                 . $len['offset'] . ' but expected ' . $this->extendedXMPOffset . ')' );
 359
 360                         return false;
 361                 }
 362
 363                 if ( $len['offset'] === 0 ) {
 364                         // if we're starting the extended block, we've probably already
 365                         // done the XMPStandard block, so reset.
 366                         $this->resetXMLParser();
 367                 }
 368
 369                 $this->extendedXMPOffset += $len['length'];
 370
 371                 $actualContent = substr( $content, 40 );
 372
 373                 if ( $this->extendedXMPOffset === strlen( $actualContent ) ) {
 374                         $atEnd = true;
 375                 } else {
 376                         $atEnd = false;
 377                 }
 378
 379                 wfDebugLog( 'XMP', __METHOD__ . 'Parsing a XMPExtended block' );
 380
 381                 return $this->parse( $actualContent, $atEnd );
 382         }
 383
 384         /**
 385          * Character data handler
 386          * Called whenever character data is found in the xmp document.
 387          *
 388          * does nothing if we're in MODE_IGNORE or if the data is whitespace
 389          * throws an error if we're not in MODE_SIMPLE (as we're not allowed to have character
 390          * data in the other modes).
 391          *
 392          * As an example, this happens when we encounter XMP like:
 393          * <exif:DigitalZoomRatio>0/10</exif:DigitalZoomRatio>
 394          * and are processing the 0/10 bit.
 395          *
 396          * @param $parser XMLParser reference to the xml parser
 397          * @param string $data Character data
 398          * @throws MWException on invalid data
 399          */
 400         function char( $parser, $data ) {
 401
 402                 $data = trim( $data );
 403                 if ( trim( $data ) === "" ) {
 404                         return;
 405                 }
 406
 407                 if ( !isset( $this->mode[0] ) ) {
 408                         throw new MWException( 'Unexpected character data before first rdf:Description element' );
 409                 }
 410
 411                 if ( $this->mode[0] === self::MODE_IGNORE ) {
 412                         return;
 413                 }
 414
 415                 if ( $this->mode[0] !== self::MODE_SIMPLE
 416                         && $this->mode[0] !== self::MODE_QDESC
 417                 ) {
 418                         throw new MWException( 'character data where not expected. (mode ' . $this->mode[0] . ')' );
 419                 }
 420
 421                 // to check, how does this handle w.s.
 422                 if ( $this->charContent === false ) {
 423                         $this->charContent = $data;
 424                 } else {
 425                         $this->charContent .= $data;
 426                 }
 427         }
 428
 429         /** When we hit a closing element in MODE_IGNORE
 430          * Check to see if this is the element we started to ignore,
 431          * in which case we get out of MODE_IGNORE
 432          *
 433          * @param string $elm Namespace of element followed by a space and then tag name of element.
 434          */
 435         private function endElementModeIgnore( $elm ) {
 436                 if ( $this->curItem[0] === $elm ) {
 437                         array_shift( $this->curItem );
 438                         array_shift( $this->mode );
 439                 }
 440         }
 441
 442         /**
 443          * Hit a closing element when in MODE_SIMPLE.
 444          * This generally means that we finished processing a
 445          * property value, and now have to save the result to the
 446          * results array
 447          *
 448          * For example, when processing:
 449          * <exif:DigitalZoomRatio>0/10</exif:DigitalZoomRatio>
 450          * this deals with when we hit </exif:DigitalZoomRatio>.
 451          *
 452          * Or it could be if we hit the end element of a property
 453          * of a compound data structure (like a member of an array).
 454          *
 455          * @param string $elm namespace, space, and tag name.
 456          */
 457         private function endElementModeSimple( $elm ) {
 458                 if ( $this->charContent !== false ) {
 459                         if ( $this->processingArray ) {
 460                                 // if we're processing an array, use the original element
 461                                 // name instead of rdf:li.
 462                                 list( $ns, $tag ) = explode( ' ', $this->curItem[0], 2 );
 463                         } else {
 464                                 list( $ns, $tag ) = explode( ' ', $elm, 2 );
 465                         }
 466                         $this->saveValue( $ns, $tag, $this->charContent );
 467
 468                         $this->charContent = false; // reset
 469                 }
 470                 array_shift( $this->curItem );
 471                 array_shift( $this->mode );
 472         }
 473
 474         /**
 475          * Hit a closing element in MODE_STRUCT, MODE_SEQ, MODE_BAG
 476          * generally means we've finished processing a nested structure.
 477          * resets some internal variables to indicate that.
 478          *
 479          * Note this means we hit the closing element not the "</rdf:Seq>".
 480          *
 481          * @par For example, when processing:
 482          * @code{,xml}
 483          * <exif:ISOSpeedRatings> <rdf:Seq> <rdf:li>64</rdf:li>
 484          *   </rdf:Seq> </exif:ISOSpeedRatings>
 485          * @endcode
 486          *
 487          * This method is called when we hit the "</exif:ISOSpeedRatings>" tag.
 488          *
 489          * @param string $elm namespace . space . tag name.
 490          * @throws MWException
 491          */
 492         private function endElementNested( $elm ) {
 493
 494                 /* cur item must be the same as $elm, unless if in MODE_STRUCT
 495                    in which case it could also be rdf:Description */
 496                 if ( $this->curItem[0] !== $elm
 497                         && !( $elm === self::NS_RDF . ' Description'
 498                                 && $this->mode[0] === self::MODE_STRUCT )
 499                 ) {
 500                         throw new MWException( "nesting mismatch. got a </$elm> but expected a </" .
 501                                 $this->curItem[0] . '>' );
 502                 }
 503
 504                 // Validate structures.
 505                 list( $ns, $tag ) = explode( ' ', $elm, 2 );
 506                 if ( isset( $this->items[$ns][$tag]['validate'] ) ) {
 507
 508                         $info =& $this->items[$ns][$tag];
 509                         $finalName = isset( $info['map_name'] )
 510                                 ? $info['map_name'] : $tag;
 511
 512                         $validate = is_array( $info['validate'] ) ? $info['validate']
 513                                 : array( 'XMPValidate', $info['validate'] );
 514
 515                         if ( !isset( $this->results['xmp-' . $info['map_group']][$finalName] ) ) {
 516                                 // This can happen if all the members of the struct failed validation.
 517                                 wfDebugLog( 'XMP', __METHOD__ . " <$ns:$tag> has no valid members." );
 518                         } elseif ( is_callable( $validate ) ) {
 519                                 $val =& $this->results['xmp-' . $info['map_group']][$finalName];
 520                                 call_user_func_array( $validate, array( $info, &$val, false ) );
 521                                 if ( is_null( $val ) ) {
 522                                         // the idea being the validation function will unset the variable if
 523                                         // its invalid.
 524                                         wfDebugLog( 'XMP', __METHOD__ . " <$ns:$tag> failed validation." );
 525                                         unset( $this->results['xmp-' . $info['map_group']][$finalName] );
 526                                 }
 527                         } else {
 528                                 wfDebugLog( 'XMP', __METHOD__ . " Validation function for $finalName ("
 529                                         . $validate[0] . '::' . $validate[1] . '()) is not callable.' );
 530                         }
 531                 }
 532
 533                 array_shift( $this->curItem );
 534                 array_shift( $this->mode );
 535                 $this->ancestorStruct = false;
 536                 $this->processingArray = false;
 537                 $this->itemLang = false;
 538         }
 539
 540         /**
 541          * Hit a closing element in MODE_LI (either rdf:Seq, or rdf:Bag )
 542          * Add information about what type of element this is.
 543          *
 544          * Note we still have to hit the outer "</property>"
 545          *
 546          * @par For example, when processing:
 547          * @code{,xml}
 548          * <exif:ISOSpeedRatings> <rdf:Seq> <rdf:li>64</rdf:li>
 549          *   </rdf:Seq> </exif:ISOSpeedRatings>
 550          * @endcode
 551          *
 552          * This method is called when we hit the "</rdf:Seq>".
 553          * (For comparison, we call endElementModeSimple when we
 554          * hit the "</rdf:li>")
 555          *
 556          * @param string $elm namespace . ' ' . element name
 557          * @throws MWException
 558          */
 559         private function endElementModeLi( $elm ) {
 560
 561                 list( $ns, $tag ) = explode( ' ', $this->curItem[0], 2 );
 562                 $info = $this->items[$ns][$tag];
 563                 $finalName = isset( $info['map_name'] )
 564                         ? $info['map_name'] : $tag;
 565
 566                 array_shift( $this->mode );
 567
 568                 if ( !isset( $this->results['xmp-' . $info['map_group']][$finalName] ) ) {
 569                         wfDebugLog( 'XMP', __METHOD__ . " Empty compund element $finalName." );
 570
 571                         return;
 572                 }
 573
 574                 if ( $elm === self::NS_RDF . ' Seq' ) {
 575                         $this->results['xmp-' . $info['map_group']][$finalName]['_type'] = 'ol';
 576                 } elseif ( $elm === self::NS_RDF . ' Bag' ) {
 577                         $this->results['xmp-' . $info['map_group']][$finalName]['_type'] = 'ul';
 578                 } elseif ( $elm === self::NS_RDF . ' Alt' ) {
 579                         // extra if needed as you could theoretically have a non-language alt.
 580                         if ( $info['mode'] === self::MODE_LANG ) {
 581                                 $this->results['xmp-' . $info['map_group']][$finalName]['_type'] = 'lang';
 582                         }
 583                 } else {
 584                         throw new MWException( __METHOD__ . " expected </rdf:seq> or </rdf:bag> but instead got $elm." );
 585                 }
 586         }
 587
 588         /**
 589          * End element while in MODE_QDESC
 590          * mostly when ending an element when we have a simple value
 591          * that has qualifiers.
 592          *
 593          * Qualifiers aren't all that common, and we don't do anything
 594          * with them.
 595          *
 596          * @param string $elm namespace and element
 597          */
 598         private function endElementModeQDesc( $elm ) {
 599
 600                 if ( $elm === self::NS_RDF . ' value' ) {
 601                         list( $ns, $tag ) = explode( ' ', $this->curItem[0], 2 );
 602                         $this->saveValue( $ns, $tag, $this->charContent );
 603
 604                         return;
 605                 } else {
 606                         array_shift( $this->mode );
 607                         array_shift( $this->curItem );
 608                 }
 609         }
 610
 611         /**
 612          * Handler for hitting a closing element.
 613          *
 614          * generally just calls a helper function depending on what
 615          * mode we're in.
 616          *
 617          * Ignores the outer wrapping elements that are optional in
 618          * xmp and have no meaning.
 619          *
 620          * @param $parser XMLParser
 621          * @param string $elm namespace . ' ' . element name
 622          * @throws MWException
 623          */
 624         function endElement( $parser, $elm ) {
 625                 if ( $elm === ( self::NS_RDF . ' RDF' )
 626                         || $elm === 'adobe:ns:meta/ xmpmeta'
 627                         || $elm === 'adobe:ns:meta/ xapmeta'
 628                 ) {
 629                         // ignore these.
 630                         return;
 631                 }
 632
 633                 if ( $elm === self::NS_RDF . ' type' ) {
 634                         // these aren't really supported properly yet.
 635                         // However, it appears they almost never used.
 636                         wfDebugLog( 'XMP', __METHOD__ . ' encountered <rdf:type>' );
 637                 }
 638
 639                 if ( strpos( $elm, ' ' ) === false ) {
 640                         // This probably shouldn't happen.
 641                         // However, there is a bug in an adobe product
 642                         // that forgets the namespace on some things.
 643                         // (Luckily they are unimportant things).
 644                         wfDebugLog( 'XMP', __METHOD__ . " Encountered </$elm> which has no namespace. Skipping." );
 645
 646                         return;
 647                 }
 648
 649                 if ( count( $this->mode[0] ) === 0 ) {
 650                         // This should never ever happen and means
 651                         // there is a pretty major bug in this class.
 652                         throw new MWException( 'Encountered end element with no mode' );
 653                 }
 654
 655                 if ( count( $this->curItem ) == 0 && $this->mode[0] !== self::MODE_INITIAL ) {
 656                         // just to be paranoid. Should always have a curItem, except for initially
 657                         // (aka during MODE_INITAL).
 658                         throw new MWException( "Hit end element </$elm> but no curItem" );
 659                 }
 660
 661                 switch ( $this->mode[0] ) {
 662                         case self::MODE_IGNORE:
 663                                 $this->endElementModeIgnore( $elm );
 664                                 break;
 665                         case self::MODE_SIMPLE:
 666                                 $this->endElementModeSimple( $elm );
 667                                 break;
 668                         case self::MODE_STRUCT:
 669                         case self::MODE_SEQ:
 670                         case self::MODE_BAG:
 671                         case self::MODE_LANG:
 672                         case self::MODE_BAGSTRUCT:
 673                                 $this->endElementNested( $elm );
 674                                 break;
 675                         case self::MODE_INITIAL:
 676                                 if ( $elm === self::NS_RDF . ' Description' ) {
 677                                         array_shift( $this->mode );
 678                                 } else {
 679                                         throw new MWException( 'Element ended unexpectedly while in MODE_INITIAL' );
 680                                 }
 681                                 break;
 682                         case self::MODE_LI:
 683                         case self::MODE_LI_LANG:
 684                                 $this->endElementModeLi( $elm );
 685                                 break;
 686                         case self::MODE_QDESC:
 687                                 $this->endElementModeQDesc( $elm );
 688                                 break;
 689                         default:
 690                                 wfDebugLog( 'XMP', __METHOD__ . " no mode (elm = $elm)" );
 691                                 break;
 692                 }
 693         }
 694
 695         /**
 696          * Hit an opening element while in MODE_IGNORE
 697          *
 698          * XMP is extensible, so ignore any tag we don't understand.
 699          *
 700          * Mostly ignores, unless we encounter the element that we are ignoring.
 701          * in which case we add it to the item stack, so we can ignore things
 702          * that are nested, correctly.
 703          *
 704          * @param string $elm namespace . ' ' . tag name
 705          */
 706         private function startElementModeIgnore( $elm ) {
 707                 if ( $elm === $this->curItem[0] ) {
 708                         array_unshift( $this->curItem, $elm );
 709                         array_unshift( $this->mode, self::MODE_IGNORE );
 710                 }
 711         }
 712
 713         /**
 714          *  Start element in MODE_BAG (unordered array)
 715          * this should always be <rdf:Bag>
 716          *
 717          * @param string $elm namespace . ' ' . tag
 718          * @throws MWException if we have an element that's not <rdf:Bag>
 719          */
 720         private function startElementModeBag( $elm ) {
 721                 if ( $elm === self::NS_RDF . ' Bag' ) {
 722                         array_unshift( $this->mode, self::MODE_LI );
 723                 } else {
 724                         throw new MWException( "Expected <rdf:Bag> but got $elm." );
 725                 }
 726         }
 727
 728         /**
 729          * Start element in MODE_SEQ (ordered array)
 730          * this should always be <rdf:Seq>
 731          *
 732          * @param string $elm namespace . ' ' . tag
 733          * @throws MWException if we have an element that's not <rdf:Seq>
 734          */
 735         private function startElementModeSeq( $elm ) {
 736                 if ( $elm === self::NS_RDF . ' Seq' ) {
 737                         array_unshift( $this->mode, self::MODE_LI );
 738                 } elseif ( $elm === self::NS_RDF . ' Bag' ) {
 739                         # bug 27105
 740                         wfDebugLog( 'XMP', __METHOD__ . ' Expected an rdf:Seq, but got an rdf:Bag. Pretending'
 741                                 . ' it is a Seq, since some buggy software is known to screw this up.' );
 742                         array_unshift( $this->mode, self::MODE_LI );
 743                 } else {
 744                         throw new MWException( "Expected <rdf:Seq> but got $elm." );
 745                 }
 746         }
 747
 748         /**
 749          * Start element in MODE_LANG (language alternative)
 750          * this should always be <rdf:Alt>
 751          *
 752          * This tag tends to be used for metadata like describe this
 753          * picture, which can be translated into multiple languages.
 754          *
 755          * XMP supports non-linguistic alternative selections,
 756          * which are really only used for thumbnails, which
 757          * we don't care about.
 758          *
 759          * @param string $elm namespace . ' ' . tag
 760          * @throws MWException if we have an element that's not <rdf:Alt>
 761          */
 762         private function startElementModeLang( $elm ) {
 763                 if ( $elm === self::NS_RDF . ' Alt' ) {
 764                         array_unshift( $this->mode, self::MODE_LI_LANG );
 765                 } else {
 766                         throw new MWException( "Expected <rdf:Seq> but got $elm." );
 767                 }
 768         }
 769
 770         /**
 771          * Handle an opening element when in MODE_SIMPLE
 772          *
 773          * This should not happen often. This is for if a simple element
 774          * already opened has a child element. Could happen for a
 775          * qualified element.
 776          *
 777          * For example:
 778          * <exif:DigitalZoomRatio><rdf:Description><rdf:value>0/10</rdf:value>
 779          *   <foo:someQualifier>Bar</foo:someQualifier> </rdf:Description>
 780          *   </exif:DigitalZoomRatio>
 781          *
 782          * This method is called when processing the <rdf:Description> element
 783          *
 784          * @param string $elm namespace and tag names separated by space.
 785          * @param array $attribs Attributes of the element.
 786          * @throws MWException
 787          */
 788         private function startElementModeSimple( $elm, $attribs ) {
 789                 if ( $elm === self::NS_RDF . ' Description' ) {
 790                         // If this value has qualifiers
 791                         array_unshift( $this->mode, self::MODE_QDESC );
 792                         array_unshift( $this->curItem, $this->curItem[0] );
 793
 794                         if ( isset( $attribs[self::NS_RDF . ' value'] ) ) {
 795                                 list( $ns, $tag ) = explode( ' ', $this->curItem[0], 2 );
 796                                 $this->saveValue( $ns, $tag, $attribs[self::NS_RDF . ' value'] );
 797                         }
 798                 } elseif ( $elm === self::NS_RDF . ' value' ) {
 799                         // This should not be here.
 800                         throw new MWException( __METHOD__ . ' Encountered <rdf:value> where it was unexpected.' );
 801                 } else {
 802                         // something else we don't recognize, like a qualifier maybe.
 803                         wfDebugLog( 'XMP', __METHOD__ .
 804                                 " Encountered element <$elm> where only expecting character data as value of " .
 805                                 $this->curItem[0] );
 806                         array_unshift( $this->mode, self::MODE_IGNORE );
 807                         array_unshift( $this->curItem, $elm );
 808                 }
 809         }
 810
 811         /**
 812          * Start an element when in MODE_QDESC.
 813          * This generally happens when a simple element has an inner
 814          * rdf:Description to hold qualifier elements.
 815          *
 816          * For example in:
 817          * <exif:DigitalZoomRatio><rdf:Description><rdf:value>0/10</rdf:value>
 818          *   <foo:someQualifier>Bar</foo:someQualifier> </rdf:Description>
 819          *   </exif:DigitalZoomRatio>
 820          * Called when processing the <rdf:value> or <foo:someQualifier>.
 821          *
 822          * @param string $elm namespace and tag name separated by a space.
 823          *
 824          */
 825         private function startElementModeQDesc( $elm ) {
 826                 if ( $elm === self::NS_RDF . ' value' ) {
 827                         return; // do nothing
 828                 } else {
 829                         // otherwise its a qualifier, which we ignore
 830                         array_unshift( $this->mode, self::MODE_IGNORE );
 831                         array_unshift( $this->curItem, $elm );
 832                 }
 833         }
 834
 835         /**
 836          * Starting an element when in MODE_INITIAL
 837          * This usually happens when we hit an element inside
 838          * the outer rdf:Description
 839          *
 840          * This is generally where most properties start.
 841          *
 842          * @param string $ns Namespace
 843          * @param string $tag tag name (without namespace prefix)
 844          * @param array $attribs array of attributes
 845          * @throws MWException
 846          */
 847         private function startElementModeInitial( $ns, $tag, $attribs ) {
 848                 if ( $ns !== self::NS_RDF ) {
 849
 850                         if ( isset( $this->items[$ns][$tag] ) ) {
 851                                 if ( isset( $this->items[$ns][$tag]['structPart'] ) ) {
 852                                         // If this element is supposed to appear only as
 853                                         // a child of a structure, but appears here (not as
 854                                         // a child of a struct), then something weird is
 855                                         // happening, so ignore this element and its children.
 856
 857                                         wfDebugLog( 'XMP', "Encountered <$ns:$tag> outside"
 858                                                 . " of its expected parent. Ignoring." );
 859
 860                                         array_unshift( $this->mode, self::MODE_IGNORE );
 861                                         array_unshift( $this->curItem, $ns . ' ' . $tag );
 862
 863                                         return;
 864                                 }
 865                                 $mode = $this->items[$ns][$tag]['mode'];
 866                                 array_unshift( $this->mode, $mode );
 867                                 array_unshift( $this->curItem, $ns . ' ' . $tag );
 868                                 if ( $mode === self::MODE_STRUCT ) {
 869                                         $this->ancestorStruct = isset( $this->items[$ns][$tag]['map_name'] )
 870                                                 ? $this->items[$ns][$tag]['map_name'] : $tag;
 871                                 }
 872                                 if ( $this->charContent !== false ) {
 873                                         // Something weird.
 874                                         // Should not happen in valid XMP.
 875                                         throw new MWException( 'tag nested in non-whitespace characters.' );
 876                                 }
 877                         } else {
 878                                 // This element is not on our list of allowed elements so ignore.
 879                                 wfDebugLog( 'XMP', __METHOD__ . " Ignoring unrecognized element <$ns:$tag>." );
 880                                 array_unshift( $this->mode, self::MODE_IGNORE );
 881                                 array_unshift( $this->curItem, $ns . ' ' . $tag );
 882
 883                                 return;
 884                         }
 885                 }
 886                 // process attributes
 887                 $this->doAttribs( $attribs );
 888         }
 889
 890         /**
 891          * Hit an opening element when in a Struct (MODE_STRUCT)
 892          * This is generally for fields of a compound property.
 893          *
 894          * Example of a struct (abbreviated; flash has more properties):
 895          *
 896          * <exif:Flash> <rdf:Description> <exif:Fired>True</exif:Fired>
 897          *  <exif:Mode>1</exif:Mode></rdf:Description></exif:Flash>
 898          *
 899          * or:
 900          *
 901          * <exif:Flash rdf:parseType='Resource'> <exif:Fired>True</exif:Fired>
 902          *  <exif:Mode>1</exif:Mode></exif:Flash>
 903          *
 904          * @param string $ns namespace
 905          * @param string $tag tag name (no ns)
 906          * @param array $attribs array of attribs w/ values.
 907          * @throws MWException
 908          */
 909         private function startElementModeStruct( $ns, $tag, $attribs ) {
 910                 if ( $ns !== self::NS_RDF ) {
 911
 912                         if ( isset( $this->items[$ns][$tag] ) ) {
 913                                 if ( isset( $this->items[$ns][$this->ancestorStruct]['children'] )
 914                                         && !isset( $this->items[$ns][$this->ancestorStruct]['children'][$tag] )
 915                                 ) {
 916                                         // This assumes that we don't have inter-namespace nesting
 917                                         // which we don't in all the properties we're interested in.
 918                                         throw new MWException( " <$tag> appeared nested in <" . $this->ancestorStruct
 919                                                 . "> where it is not allowed." );
 920                                 }
 921                                 array_unshift( $this->mode, $this->items[$ns][$tag]['mode'] );
 922                                 array_unshift( $this->curItem, $ns . ' ' . $tag );
 923                                 if ( $this->charContent !== false ) {
 924                                         // Something weird.
 925                                         // Should not happen in valid XMP.
 926                                         throw new MWException( "tag <$tag> nested in non-whitespace characters (" .
 927                                                 $this->charContent . ")." );
 928                                 }
 929                         } else {
 930                                 array_unshift( $this->mode, self::MODE_IGNORE );
 931                                 array_unshift( $this->curItem, $elm );
 932
 933                                 return;
 934                         }
 935                 }
 936
 937                 if ( $ns === self::NS_RDF && $tag === 'Description' ) {
 938                         $this->doAttribs( $attribs );
 939                         array_unshift( $this->mode, self::MODE_STRUCT );
 940                         array_unshift( $this->curItem, $this->curItem[0] );
 941                 }
 942         }
 943
 944         /**
 945          * opening element in MODE_LI
 946          * process elements of arrays.
 947          *
 948          * Example:
 949          * <exif:ISOSpeedRatings> <rdf:Seq> <rdf:li>64</rdf:li>
 950          *   </rdf:Seq> </exif:ISOSpeedRatings>
 951          * This method is called when we hit the <rdf:li> element.
 952          *
 953          * @param string $elm namespace . ' ' . tagname
 954          * @param array $attribs Attributes. (needed for BAGSTRUCTS)
 955          * @throws MWException if gets a tag other than <rdf:li>
 956          */
 957         private function startElementModeLi( $elm, $attribs ) {
 958                 if ( ( $elm ) !== self::NS_RDF . ' li' ) {
 959                         throw new MWException( "<rdf:li> expected but got $elm." );
 960                 }
 961
 962                 if ( !isset( $this->mode[1] ) ) {
 963                         // This should never ever ever happen. Checking for it
 964                         // to be paranoid.
 965                         throw new MWException( 'In mode Li, but no 2xPrevious mode!' );
 966                 }
 967
 968                 if ( $this->mode[1] === self::MODE_BAGSTRUCT ) {
 969                         // This list item contains a compound (STRUCT) value.
 970                         array_unshift( $this->mode, self::MODE_STRUCT );
 971                         array_unshift( $this->curItem, $elm );
 972                         $this->processingArray = true;
 973
 974                         if ( !isset( $this->curItem[1] ) ) {
 975                                 // be paranoid.
 976                                 throw new MWException( 'Can not find parent of BAGSTRUCT.' );
 977                         }
 978                         list( $curNS, $curTag ) = explode( ' ', $this->curItem[1] );
 979                         $this->ancestorStruct = isset( $this->items[$curNS][$curTag]['map_name'] )
 980                                 ? $this->items[$curNS][$curTag]['map_name'] : $curTag;
 981
 982                         $this->doAttribs( $attribs );
 983                 } else {
 984                         // Normal BAG or SEQ containing simple values.
 985                         array_unshift( $this->mode, self::MODE_SIMPLE );
 986                         // need to add curItem[0] on again since one is for the specific item
 987                         // and one is for the entire group.
 988                         array_unshift( $this->curItem, $this->curItem[0] );
 989                         $this->processingArray = true;
 990                 }
 991         }
 992
 993         /**
 994          * Opening element in MODE_LI_LANG.
 995          * process elements of language alternatives
 996          *
 997          * Example:
 998          * <dc:title> <rdf:Alt> <rdf:li xml:lang="x-default">My house
 999          *  </rdf:li> </rdf:Alt> </dc:title>
1000          *
1001          * This method is called when we hit the <rdf:li> element.
1002          *
1003          * @param string $elm namespace . ' ' . tag
1004          * @param array $attribs array of elements (most importantly xml:lang)
1005          * @throws MWException if gets a tag other than <rdf:li> or if no xml:lang
1006          */
1007         private function startElementModeLiLang( $elm, $attribs ) {
1008                 if ( $elm !== self::NS_RDF . ' li' ) {
1009                         throw new MWException( __METHOD__ . " <rdf:li> expected but got $elm." );
1010                 }
1011                 if ( !isset( $attribs[self::NS_XML . ' lang'] )
1012                         || !preg_match( '/^[-A-Za-z0-9]{2,}$/D', $attribs[self::NS_XML . ' lang'] )
1013                 ) {
1014                         throw new MWException( __METHOD__
1015                                 . " <rdf:li> did not contain, or has invalid xml:lang attribute in lang alternative" );
1016                 }
1017
1018                 // Lang is case-insensitive.
1019                 $this->itemLang = strtolower( $attribs[self::NS_XML . ' lang'] );
1020
1021                 // need to add curItem[0] on again since one is for the specific item
1022                 // and one is for the entire group.
1023                 array_unshift( $this->curItem, $this->curItem[0] );
1024                 array_unshift( $this->mode, self::MODE_SIMPLE );
1025                 $this->processingArray = true;
1026         }
1027
1028         /**
1029          * Hits an opening element.
1030          * Generally just calls a helper based on what MODE we're in.
1031          * Also does some initial set up for the wrapper element
1032          *
1033          * @param $parser XMLParser
1034          * @param string $elm namespace "<space>" element
1035          * @param array $attribs attribute name => value
1036          * @throws MWException
1037          */
1038         function startElement( $parser, $elm, $attribs ) {
1039
1040                 if ( $elm === self::NS_RDF . ' RDF'
1041                         || $elm === 'adobe:ns:meta/ xmpmeta'
1042                         || $elm === 'adobe:ns:meta/ xapmeta'
1043                 ) {
1044                         /* ignore. */
1045                         return;
1046                 } elseif ( $elm === self::NS_RDF . ' Description' ) {
1047                         if ( count( $this->mode ) === 0 ) {
1048                                 // outer rdf:desc
1049                                 array_unshift( $this->mode, self::MODE_INITIAL );
1050                         }
1051                 } elseif ( $elm === self::NS_RDF . ' type' ) {
1052                         // This doesn't support rdf:type properly.
1053                         // In practise I have yet to see a file that
1054                         // uses this element, however it is mentioned
1055                         // on page 25 of part 1 of the xmp standard.
1056                         //
1057                         // also it seems as if exiv2 and exiftool do not support
1058                         // this either (That or I misunderstand the standard)
1059                         wfDebugLog( 'XMP', __METHOD__ . ' Encountered <rdf:type> which isn\'t currently supported' );
1060                 }
1061
1062                 if ( strpos( $elm, ' ' ) === false ) {
1063                         // This probably shouldn't happen.
1064                         wfDebugLog( 'XMP', __METHOD__ . " Encountered <$elm> which has no namespace. Skipping." );
1065
1066                         return;
1067                 }
1068
1069                 list( $ns, $tag ) = explode( ' ', $elm, 2 );
1070
1071                 if ( count( $this->mode ) === 0 ) {
1072                         // This should not happen.
1073                         throw new MWException( 'Error extracting XMP, '
1074                                 . "encountered <$elm> with no mode" );
1075                 }
1076
1077                 switch ( $this->mode[0] ) {
1078                         case self::MODE_IGNORE:
1079                                 $this->startElementModeIgnore( $elm );
1080                                 break;
1081                         case self::MODE_SIMPLE:
1082                                 $this->startElementModeSimple( $elm, $attribs );
1083                                 break;
1084                         case self::MODE_INITIAL:
1085                                 $this->startElementModeInitial( $ns, $tag, $attribs );
1086                                 break;
1087                         case self::MODE_STRUCT:
1088                                 $this->startElementModeStruct( $ns, $tag, $attribs );
1089                                 break;
1090                         case self::MODE_BAG:
1091                         case self::MODE_BAGSTRUCT:
1092                                 $this->startElementModeBag( $elm );
1093                                 break;
1094                         case self::MODE_SEQ:
1095                                 $this->startElementModeSeq( $elm );
1096                                 break;
1097                         case self::MODE_LANG:
1098                                 $this->startElementModeLang( $elm );
1099                                 break;
1100                         case self::MODE_LI_LANG:
1101                                 $this->startElementModeLiLang( $elm, $attribs );
1102                                 break;
1103                         case self::MODE_LI:
1104                                 $this->startElementModeLi( $elm, $attribs );
1105                                 break;
1106                         case self::MODE_QDESC:
1107                                 $this->startElementModeQDesc( $elm );
1108                                 break;
1109                         default:
1110                                 throw new MWException( 'StartElement in unknown mode: ' . $this->mode[0] );
1111                 }
1112         }
1113
1114         // @codingStandardsIgnoreStart Long line that cannot be broken
1115         /**
1116          * Process attributes.
1117          * Simple values can be stored as either a tag or attribute
1118          *
1119          * Often the initial "<rdf:Description>" tag just has all the simple
1120          * properties as attributes.
1121          *
1122          * @par Example:
1123          * @code
1124          * <rdf:Description rdf:about="" xmlns:exif="http://ns.adobe.com/exif/1.0/" exif:DigitalZoomRatio="0/10">
1125          * @endcode
1126          *
1127          * @param array $attribs attribute=>value array.
1128          * @throws MWException
1129          */
1130         // @codingStandardsIgnoreEnd
1131         private function doAttribs( $attribs ) {
1132                 // first check for rdf:parseType attribute, as that can change
1133                 // how the attributes are interperted.
1134
1135                 if ( isset( $attribs[self::NS_RDF . ' parseType'] )
1136                         && $attribs[self::NS_RDF . ' parseType'] === 'Resource'
1137                         && $this->mode[0] === self::MODE_SIMPLE
1138                 ) {
1139                         // this is equivalent to having an inner rdf:Description
1140                         $this->mode[0] = self::MODE_QDESC;
1141                 }
1142                 foreach ( $attribs as $name => $val ) {
1143                         if ( strpos( $name, ' ' ) === false ) {
1144                                 // This shouldn't happen, but so far some old software forgets namespace
1145                                 // on rdf:about.
1146                                 wfDebugLog( 'XMP', __METHOD__ . ' Encountered non-namespaced attribute: '
1147                                         . " $name=\"$val\". Skipping. " );
1148                                 continue;
1149                         }
1150                         list( $ns, $tag ) = explode( ' ', $name, 2 );
1151                         if ( $ns === self::NS_RDF ) {
1152                                 if ( $tag === 'value' || $tag === 'resource' ) {
1153                                         // resource is for url.
1154                                         // value attribute is a weird way of just putting the contents.
1155                                         $this->char( $this->xmlParser, $val );
1156                                 }
1157                         } elseif ( isset( $this->items[$ns][$tag] ) ) {
1158                                 if ( $this->mode[0] === self::MODE_SIMPLE ) {
1159                                         throw new MWException( __METHOD__
1160                                                 . " $ns:$tag found as attribute where not allowed" );
1161                                 }
1162                                 $this->saveValue( $ns, $tag, $val );
1163                         } else {
1164                                 wfDebugLog( 'XMP', __METHOD__ . " Ignoring unrecognized element <$ns:$tag>." );
1165                         }
1166                 }
1167         }
1168
1169         /**
1170          * Given an extracted value, save it to results array
1171          *
1172          * note also uses $this->ancestorStruct and
1173          * $this->processingArray to determine what name to
1174          * save the value under. (in addition to $tag).
1175          *
1176          * @param string $ns namespace of tag this is for
1177          * @param string $tag tag name
1178          * @param string $val value to save
1179          */
1180         private function saveValue( $ns, $tag, $val ) {
1181
1182                 $info =& $this->items[$ns][$tag];
1183                 $finalName = isset( $info['map_name'] )
1184                         ? $info['map_name'] : $tag;
1185                 if ( isset( $info['validate'] ) ) {
1186                         $validate = is_array( $info['validate'] ) ? $info['validate']
1187                                 : array( 'XMPValidate', $info['validate'] );
1188
1189                         if ( is_callable( $validate ) ) {
1190                                 call_user_func_array( $validate, array( $info, &$val, true ) );
1191                                 // the reasoning behind using &$val instead of using the return value
1192                                 // is to be consistent between here and validating structures.
1193                                 if ( is_null( $val ) ) {
1194                                         wfDebugLog( 'XMP', __METHOD__ . " <$ns:$tag> failed validation." );
1195
1196                                         return;
1197                                 }
1198                         } else {
1199                                 wfDebugLog( 'XMP', __METHOD__ . " Validation function for $finalName ("
1200                                         . $validate[0] . '::' . $validate[1] . '()) is not callable.' );
1201                         }
1202                 }
1203
1204                 if ( $this->ancestorStruct && $this->processingArray ) {
1205                         // Aka both an array and a struct. ( self::MODE_BAGSTRUCT )
1206                         $this->results['xmp-' . $info['map_group']][$this->ancestorStruct][][$finalName] = $val;
1207                 } elseif ( $this->ancestorStruct ) {
1208                         $this->results['xmp-' . $info['map_group']][$this->ancestorStruct][$finalName] = $val;
1209                 } elseif ( $this->processingArray ) {
1210                         if ( $this->itemLang === false ) {
1211                                 // normal array
1212                                 $this->results['xmp-' . $info['map_group']][$finalName][] = $val;
1213                         } else {
1214                                 // lang array.
1215                                 $this->results['xmp-' . $info['map_group']][$finalName][$this->itemLang] = $val;
1216                         }
1217                 } else {
1218                         $this->results['xmp-' . $info['map_group']][$finalName] = $val;
1219                 }
1220         }
1221 }