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authorPierre Schmitz <pierre@archlinux.de>2011-12-03 13:29:22 +0100
committerPierre Schmitz <pierre@archlinux.de>2011-12-03 13:29:22 +0100
commitca32f08966f1b51fcb19460f0996bb0c4048e6fe (patch)
treeec04cc15b867bc21eedca904cea9af0254531a11 /includes/media/XMP.php
parenta22fbfc60f36f5f7ee10d5ae6fe347340c2ee67c (diff)
Update to MediaWiki 1.18.0
* also update ArchLinux skin to chagnes in MonoBook * Use only css to hide our menu bar when printing
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+<?php
+/**
+* Class for reading xmp data containing properties relevant to
+* images, and spitting out an array that FormatExif accepts.
+*
+* Note, this is not meant to recognize every possible thing you can
+* encode in XMP. It should recognize all the properties we want.
+* For example it doesn't have support for structures with multiple
+* nesting levels, as none of the properties we're supporting use that
+* feature. If it comes across properties it doesn't recognize, it should
+* ignore them.
+*
+* The public methods one would call in this class are
+* - parse( $content )
+* Reads in xmp content.
+* Can potentially be called multiple times with partial data each time.
+* - parseExtended( $content )
+* Reads XMPExtended blocks (jpeg files only).
+* - getResults
+* Outputs a results array.
+*
+* Note XMP kind of looks like rdf. They are not the same thing - XMP is
+* encoded as a specific subset of rdf. This class can read XMP. It cannot
+* read rdf.
+*
+*/
+class XMPReader {
+
+ private $curItem = array(); // array to hold the current element (and previous element, and so on)
+ private $ancestorStruct = false; // the structure name when processing nested structures.
+ private $charContent = false; // temporary holder for character data that appears in xmp doc.
+ private $mode = array(); // stores the state the xmpreader is in (see MODE_FOO constants)
+ private $results = array(); // array to hold results
+ private $processingArray = false; // if we're doing a seq or bag.
+ private $itemLang = false; // used for lang alts only
+
+ private $xmlParser;
+ private $charset = false;
+ private $extendedXMPOffset = 0;
+
+ protected $items;
+
+ /**
+ * These are various mode constants.
+ * they are used to figure out what to do
+ * with an element when its encountered.
+ *
+ * For example, MODE_IGNORE is used when processing
+ * a property we're not interested in. So if a new
+ * element pops up when we're in that mode, we ignore it.
+ */
+ const MODE_INITIAL = 0;
+ const MODE_IGNORE = 1;
+ const MODE_LI = 2;
+ const MODE_LI_LANG = 3;
+ const MODE_QDESC = 4;
+
+ // The following MODE constants are also used in the
+ // $items array to denote what type of property the item is.
+ const MODE_SIMPLE = 10;
+ const MODE_STRUCT = 11; // structure (associative array)
+ const MODE_SEQ = 12; // ordered list
+ const MODE_BAG = 13; // unordered list
+ const MODE_LANG = 14;
+ const MODE_ALT = 15; // non-language alt. Currently not implemented, and not needed atm.
+ const MODE_BAGSTRUCT = 16; // A BAG of Structs.
+
+ const NS_RDF = 'http://www.w3.org/1999/02/22-rdf-syntax-ns#';
+ const NS_XML = 'http://www.w3.org/XML/1998/namespace';
+
+
+ /**
+ * Constructor.
+ *
+ * Primary job is to initialize the XMLParser
+ */
+ function __construct() {
+
+ if ( !function_exists( 'xml_parser_create_ns' ) ) {
+ // this should already be checked by this point
+ throw new MWException( 'XMP support requires XML Parser' );
+ }
+
+ $this->items = XMPInfo::getItems();
+
+ $this->resetXMLParser();
+
+ }
+ /**
+ * Main use is if a single item has multiple xmp documents describing it.
+ * For example in jpeg's with extendedXMP
+ */
+ private function resetXMLParser() {
+
+ if ($this->xmlParser) {
+ //is this needed?
+ xml_parser_free( $this->xmlParser );
+ }
+
+ $this->xmlParser = xml_parser_create_ns( 'UTF-8', ' ' );
+ xml_parser_set_option( $this->xmlParser, XML_OPTION_CASE_FOLDING, 0 );
+ xml_parser_set_option( $this->xmlParser, XML_OPTION_SKIP_WHITE, 1 );
+
+ xml_set_element_handler( $this->xmlParser,
+ array( $this, 'startElement' ),
+ array( $this, 'endElement' ) );
+
+ xml_set_character_data_handler( $this->xmlParser, array( $this, 'char' ) );
+ }
+
+ /** Destroy the xml parser
+ *
+ * Not sure if this is actually needed.
+ */
+ function __destruct() {
+ // not sure if this is needed.
+ xml_parser_free( $this->xmlParser );
+ }
+
+ /** Get the result array. Do some post-processing before returning
+ * the array, and transform any metadata that is special-cased.
+ *
+ * @return Array array of results as an array of arrays suitable for
+ * FormatMetadata::getFormattedData().
+ */
+ public function getResults() {
+ // xmp-special is for metadata that affects how stuff
+ // is extracted. For example xmpNote:HasExtendedXMP.
+
+ // It is also used to handle photoshop:AuthorsPosition
+ // which is weird and really part of another property,
+ // see 2:85 in IPTC. See also pg 21 of IPTC4XMP standard.
+ // The location fields also use it.
+
+ $data = $this->results;
+
+ wfRunHooks('XMPGetResults', Array(&$data));
+
+ if ( isset( $data['xmp-special']['AuthorsPosition'] )
+ && is_string( $data['xmp-special']['AuthorsPosition'] )
+ && isset( $data['xmp-general']['Artist'][0] )
+ ) {
+ // Note, if there is more than one creator,
+ // this only applies to first. This also will
+ // only apply to the dc:Creator prop, not the
+ // exif:Artist prop.
+
+ $data['xmp-general']['Artist'][0] =
+ $data['xmp-special']['AuthorsPosition'] . ', '
+ . $data['xmp-general']['Artist'][0];
+ }
+
+ // Go through the LocationShown and LocationCreated
+ // changing it to the non-hierarchal form used by
+ // the other location fields.
+
+ if ( isset( $data['xmp-special']['LocationShown'][0] )
+ && is_array( $data['xmp-special']['LocationShown'][0] )
+ ) {
+ // the is_array is just paranoia. It should always
+ // be an array.
+ foreach( $data['xmp-special']['LocationShown'] as $loc ) {
+ if ( !is_array( $loc ) ) {
+ // To avoid copying over the _type meta-fields.
+ continue;
+ }
+ foreach( $loc as $field => $val ) {
+ $data['xmp-general'][$field . 'Dest'][] = $val;
+ }
+ }
+ }
+ if ( isset( $data['xmp-special']['LocationCreated'][0] )
+ && is_array( $data['xmp-special']['LocationCreated'][0] )
+ ) {
+ // the is_array is just paranoia. It should always
+ // be an array.
+ foreach( $data['xmp-special']['LocationCreated'] as $loc ) {
+ if ( !is_array( $loc ) ) {
+ // To avoid copying over the _type meta-fields.
+ continue;
+ }
+ foreach( $loc as $field => $val ) {
+ $data['xmp-general'][$field . 'Created'][] = $val;
+ }
+ }
+ }
+
+
+ // We don't want to return the special values, since they're
+ // special and not info to be stored about the file.
+ unset( $data['xmp-special'] );
+
+ // Convert GPSAltitude to negative if below sea level.
+ if ( isset( $data['xmp-exif']['GPSAltitudeRef'] ) ) {
+ if ( $data['xmp-exif']['GPSAltitudeRef'] == '1'
+ && isset( $data['xmp-exif']['GPSAltitude'] )
+ ) {
+ $data['xmp-exif']['GPSAltitude'] *= -1;
+ }
+ unset( $data['xmp-exif']['GPSAltitudeRef'] );
+ }
+
+ return $data;
+ }
+
+ /**
+ * Main function to call to parse XMP. Use getResults to
+ * get results.
+ *
+ * Also catches any errors during processing, writes them to
+ * debug log, blanks result array and returns false.
+ *
+ * @param String: $content XMP data
+ * @param Boolean: $allOfIt If this is all the data (true) or if its split up (false). Default true
+ * @param Boolean: $reset - does xml parser need to be reset. Default false
+ * @return Boolean success.
+ */
+ public function parse( $content, $allOfIt = true, $reset = false ) {
+ if ( $reset ) {
+ $this->resetXMLParser();
+ }
+ try {
+
+ // detect encoding by looking for BOM which is supposed to be in processing instruction.
+ // see page 12 of http://www.adobe.com/devnet/xmp/pdfs/XMPSpecificationPart3.pdf
+ if ( !$this->charset ) {
+ $bom = array();
+ if ( preg_match( '/\xEF\xBB\xBF|\xFE\xFF|\x00\x00\xFE\xFF|\xFF\xFE\x00\x00|\xFF\xFE/',
+ $content, $bom )
+ ) {
+ switch ( $bom[0] ) {
+ case "\xFE\xFF":
+ $this->charset = 'UTF-16BE';
+ break;
+ case "\xFF\xFE":
+ $this->charset = 'UTF-16LE';
+ break;
+ case "\x00\x00\xFE\xFF":
+ $this->charset = 'UTF-32BE';
+ break;
+ case "\xFF\xFE\x00\x00":
+ $this->charset = 'UTF-32LE';
+ break;
+ case "\xEF\xBB\xBF":
+ $this->charset = 'UTF-8';
+ break;
+ default:
+ //this should be impossible to get to
+ throw new MWException("Invalid BOM");
+ break;
+
+ }
+
+ } else {
+ // standard specifically says, if no bom assume utf-8
+ $this->charset = 'UTF-8';
+ }
+ }
+ if ( $this->charset !== 'UTF-8' ) {
+ //don't convert if already utf-8
+ wfSuppressWarnings();
+ $content = iconv( $this->charset, 'UTF-8//IGNORE', $content );
+ wfRestoreWarnings();
+ }
+
+ $ok = xml_parse( $this->xmlParser, $content, $allOfIt );
+ if ( !$ok ) {
+ $error = xml_error_string( xml_get_error_code( $this->xmlParser ) );
+ $where = 'line: ' . xml_get_current_line_number( $this->xmlParser )
+ . ' column: ' . xml_get_current_column_number( $this->xmlParser )
+ . ' byte offset: ' . xml_get_current_byte_index( $this->xmlParser );
+
+ wfDebugLog( 'XMP', "XMPReader::parse : Error reading XMP content: $error ($where)" );
+ $this->results = array(); // blank if error.
+ return false;
+ }
+ } catch ( MWException $e ) {
+ wfDebugLog( 'XMP', 'XMP parse error: ' . $e );
+ $this->results = array();
+ return false;
+ }
+ return true;
+ }
+
+ /** Entry point for XMPExtended blocks in jpeg files
+ *
+ * @todo In serious need of testing
+ * @see http://www.adobe.ge/devnet/xmp/pdfs/XMPSpecificationPart3.pdf XMP spec part 3 page 20
+ * @param String $content XMPExtended block minus the namespace signature
+ * @return Boolean If it succeeded.
+ */
+ public function parseExtended( $content ) {
+ // @todo FIXME: This is untested. Hard to find example files
+ // or programs that make such files..
+ $guid = substr( $content, 0, 32 );
+ if ( !isset( $this->results['xmp-special']['HasExtendedXMP'] )
+ || $this->results['xmp-special']['HasExtendedXMP'] !== $guid ) {
+ wfDebugLog('XMP', __METHOD__ . " Ignoring XMPExtended block due to wrong guid (guid= '$guid' )");
+ return false;
+ }
+ $len = unpack( 'Nlength/Noffset', substr( $content, 32, 8 ) );
+
+ if (!$len || $len['length'] < 4 || $len['offset'] < 0 || $len['offset'] > $len['length'] ) {
+ wfDebugLog('XMP', __METHOD__ . 'Error reading extended XMP block, invalid length or offset.');
+ return false;
+ }
+
+
+ // we're not very robust here. we should accept it in the wrong order. To quote
+ // the xmp standard:
+ // "A JPEG writer should write the ExtendedXMP marker segments in order, immediately following the
+ // StandardXMP. However, the JPEG standard does not require preservation of marker segment order. A
+ // robust JPEG reader should tolerate the marker segments in any order."
+ //
+ // otoh the probability that an image will have more than 128k of metadata is rather low...
+ // so the probability that it will have > 128k, and be in the wrong order is very low...
+
+ if ( $len['offset'] !== $this->extendedXMPOffset ) {
+ wfDebugLog('XMP', __METHOD__ . 'Ignoring XMPExtended block due to wrong order. (Offset was '
+ . $len['offset'] . ' but expected ' . $this->extendedXMPOffset . ')');
+ return false;
+ }
+
+ if ( $len['offset'] === 0 ) {
+ // if we're starting the extended block, we've probably already
+ // done the XMPStandard block, so reset.
+ $this->resetXMLParser();
+ }
+
+ $this->extendedXMPOffset += $len['length'];
+
+ $actualContent = substr( $content, 40 );
+
+ if ( $this->extendedXMPOffset === strlen( $actualContent ) ) {
+ $atEnd = true;
+ } else {
+ $atEnd = false;
+ }
+
+ wfDebugLog('XMP', __METHOD__ . 'Parsing a XMPExtended block');
+ return $this->parse( $actualContent, $atEnd );
+ }
+
+ /**
+ * Character data handler
+ * Called whenever character data is found in the xmp document.
+ *
+ * does nothing if we're in MODE_IGNORE or if the data is whitespace
+ * throws an error if we're not in MODE_SIMPLE (as we're not allowed to have character
+ * data in the other modes).
+ *
+ * As an example, this happens when we encounter XMP like:
+ * <exif:DigitalZoomRatio>0/10</exif:DigitalZoomRatio>
+ * and are processing the 0/10 bit.
+ *
+ * @param $parser XMLParser reference to the xml parser
+ * @param $data String Character data
+ * @throws MWException on invalid data
+ */
+ function char( $parser, $data ) {
+
+ $data = trim( $data );
+ if ( trim( $data ) === "" ) {
+ return;
+ }
+
+ if ( !isset( $this->mode[0] ) ) {
+ throw new MWException( 'Unexpected character data before first rdf:Description element' );
+ }
+
+ if ( $this->mode[0] === self::MODE_IGNORE ) return;
+
+ if ( $this->mode[0] !== self::MODE_SIMPLE
+ && $this->mode[0] !== self::MODE_QDESC
+ ) {
+ throw new MWException( 'character data where not expected. (mode ' . $this->mode[0] . ')' );
+ }
+
+ // to check, how does this handle w.s.
+ if ( $this->charContent === false ) {
+ $this->charContent = $data;
+ } else {
+ $this->charContent .= $data;
+ }
+
+ }
+
+ /** When we hit a closing element in MODE_IGNORE
+ * Check to see if this is the element we started to ignore,
+ * in which case we get out of MODE_IGNORE
+ *
+ * @param $elm String Namespace of element followed by a space and then tag name of element.
+ */
+ private function endElementModeIgnore ( $elm ) {
+
+ if ( $this->curItem[0] === $elm ) {
+ array_shift( $this->curItem );
+ array_shift( $this->mode );
+ }
+ return;
+
+ }
+
+ /**
+ * Hit a closing element when in MODE_SIMPLE.
+ * This generally means that we finished processing a
+ * property value, and now have to save the result to the
+ * results array
+ *
+ * For example, when processing:
+ * <exif:DigitalZoomRatio>0/10</exif:DigitalZoomRatio>
+ * this deals with when we hit </exif:DigitalZoomRatio>.
+ *
+ * Or it could be if we hit the end element of a property
+ * of a compound data structure (like a member of an array).
+ *
+ * @param $elm String namespace, space, and tag name.
+ */
+ private function endElementModeSimple ( $elm ) {
+ if ( $this->charContent !== false ) {
+ if ( $this->processingArray ) {
+ // if we're processing an array, use the original element
+ // name instead of rdf:li.
+ list( $ns, $tag ) = explode( ' ', $this->curItem[0], 2 );
+ } else {
+ list( $ns, $tag ) = explode( ' ', $elm, 2 );
+ }
+ $this->saveValue( $ns, $tag, $this->charContent );
+
+ $this->charContent = false; // reset
+ }
+ array_shift( $this->curItem );
+ array_shift( $this->mode );
+
+ }
+
+ /**
+ * Hit a closing element in MODE_STRUCT, MODE_SEQ, MODE_BAG
+ * generally means we've finished processing a nested structure.
+ * resets some internal variables to indicate that.
+ *
+ * Note this means we hit the </closing element> not the </rdf:Seq>.
+ *
+ * For example, when processing:
+ * <exif:ISOSpeedRatings> <rdf:Seq> <rdf:li>64</rdf:li>
+ * </rdf:Seq> </exif:ISOSpeedRatings>
+ *
+ * This method is called when we hit the </exif:ISOSpeedRatings> tag.
+ *
+ * @param $elm String namespace . space . tag name.
+ */
+ private function endElementNested( $elm ) {
+
+ /* cur item must be the same as $elm, unless if in MODE_STRUCT
+ in which case it could also be rdf:Description */
+ if ( $this->curItem[0] !== $elm
+ && !( $elm === self::NS_RDF . ' Description'
+ && $this->mode[0] === self::MODE_STRUCT )
+ ) {
+ throw new MWException( "nesting mismatch. got a </$elm> but expected a </" . $this->curItem[0] . '>' );
+ }
+
+ // Validate structures.
+ list( $ns, $tag ) = explode( ' ', $elm, 2 );
+ if ( isset( $this->items[$ns][$tag]['validate'] ) ) {
+
+ $info =& $this->items[$ns][$tag];
+ $finalName = isset( $info['map_name'] )
+ ? $info['map_name'] : $tag;
+
+ $validate = is_array( $info['validate'] ) ? $info['validate']
+ : array( 'XMPValidate', $info['validate'] );
+
+ if ( !isset( $this->results['xmp-' . $info['map_group']][$finalName] ) ) {
+ // This can happen if all the members of the struct failed validation.
+ wfDebugLog( 'XMP', __METHOD__ . " <$ns:$tag> has no valid members." );
+
+ } elseif ( is_callable( $validate ) ) {
+ $val =& $this->results['xmp-' . $info['map_group']][$finalName];
+ call_user_func_array( $validate, array( $info, &$val, false ) );
+ if ( is_null( $val ) ) {
+ // the idea being the validation function will unset the variable if
+ // its invalid.
+ wfDebugLog( 'XMP', __METHOD__ . " <$ns:$tag> failed validation." );
+ unset( $this->results['xmp-' . $info['map_group']][$finalName] );
+ }
+ } else {
+ wfDebugLog( 'XMP', __METHOD__ . " Validation function for $finalName ("
+ . $validate[0] . '::' . $validate[1] . '()) is not callable.' );
+ }
+ }
+
+ array_shift( $this->curItem );
+ array_shift( $this->mode );
+ $this->ancestorStruct = false;
+ $this->processingArray = false;
+ $this->itemLang = false;
+ }
+
+ /**
+ * Hit a closing element in MODE_LI (either rdf:Seq, or rdf:Bag )
+ * Add information about what type of element this is.
+ *
+ * Note we still have to hit the outer </property>
+ *
+ * For example, when processing:
+ * <exif:ISOSpeedRatings> <rdf:Seq> <rdf:li>64</rdf:li>
+ * </rdf:Seq> </exif:ISOSpeedRatings>
+ *
+ * This method is called when we hit the </rdf:Seq>.
+ * (For comparison, we call endElementModeSimple when we
+ * hit the </rdf:li>)
+ *
+ * @param $elm String namespace . ' ' . element name
+ */
+ private function endElementModeLi( $elm ) {
+
+ list( $ns, $tag ) = explode( ' ', $this->curItem[0], 2 );
+ $info = $this->items[$ns][$tag];
+ $finalName = isset( $info['map_name'] )
+ ? $info['map_name'] : $tag;
+
+ array_shift( $this->mode );
+
+ if ( !isset( $this->results['xmp-' . $info['map_group']][$finalName] ) ) {
+ wfDebugLog( 'XMP', __METHOD__ . " Empty compund element $finalName." );
+ return;
+ }
+
+ if ( $elm === self::NS_RDF . ' Seq' ) {
+ $this->results['xmp-' . $info['map_group']][$finalName]['_type'] = 'ol';
+ } elseif ( $elm === self::NS_RDF . ' Bag' ) {
+ $this->results['xmp-' . $info['map_group']][$finalName]['_type'] = 'ul';
+ } elseif ( $elm === self::NS_RDF . ' Alt' ) {
+ // extra if needed as you could theoretically have a non-language alt.
+ if ( $info['mode'] === self::MODE_LANG ) {
+ $this->results['xmp-' . $info['map_group']][$finalName]['_type'] = 'lang';
+ }
+
+ } else {
+ throw new MWException( __METHOD__ . " expected </rdf:seq> or </rdf:bag> but instead got $elm." );
+ }
+ }
+
+ /**
+ * End element while in MODE_QDESC
+ * mostly when ending an element when we have a simple value
+ * that has qualifiers.
+ *
+ * Qualifiers aren't all that common, and we don't do anything
+ * with them.
+ *
+ * @param $elm String namespace and element
+ */
+ private function endElementModeQDesc( $elm ) {
+
+ if ( $elm === self::NS_RDF . ' value' ) {
+ list( $ns, $tag ) = explode( ' ', $this->curItem[0], 2 );
+ $this->saveValue( $ns, $tag, $this->charContent );
+ return;
+ } else {
+ array_shift( $this->mode );
+ array_shift( $this->curItem );
+ }
+
+
+ }
+
+ /**
+ * Handler for hitting a closing element.
+ *
+ * generally just calls a helper function depending on what
+ * mode we're in.
+ *
+ * Ignores the outer wrapping elements that are optional in
+ * xmp and have no meaning.
+ *
+ * @param $parser XMLParser
+ * @param $elm String namespace . ' ' . element name
+ */
+ function endElement( $parser, $elm ) {
+ if ( $elm === ( self::NS_RDF . ' RDF' )
+ || $elm === 'adobe:ns:meta/ xmpmeta'
+ || $elm === 'adobe:ns:meta/ xapmeta' )
+ {
+ // ignore these.
+ return;
+ }
+
+ if ( $elm === self::NS_RDF . ' type' ) {
+ // these aren't really supported properly yet.
+ // However, it appears they almost never used.
+ wfDebugLog( 'XMP', __METHOD__ . ' encountered <rdf:type>' );
+ }
+
+ if ( strpos( $elm, ' ' ) === false ) {
+ // This probably shouldn't happen.
+ // However, there is a bug in an adobe product
+ // that forgets the namespace on some things.
+ // (Luckily they are unimportant things).
+ wfDebugLog( 'XMP', __METHOD__ . " Encountered </$elm> which has no namespace. Skipping." );
+ return;
+ }
+
+ if ( count( $this->mode[0] ) === 0 ) {
+ // This should never ever happen and means
+ // there is a pretty major bug in this class.
+ throw new MWException( 'Encountered end element with no mode' );
+ }
+
+ if ( count( $this->curItem ) == 0 && $this->mode[0] !== self::MODE_INITIAL ) {
+ // just to be paranoid. Should always have a curItem, except for initially
+ // (aka during MODE_INITAL).
+ throw new MWException( "Hit end element </$elm> but no curItem" );
+ }
+
+ switch( $this->mode[0] ) {
+ case self::MODE_IGNORE:
+ $this->endElementModeIgnore( $elm );
+ break;
+ case self::MODE_SIMPLE:
+ $this->endElementModeSimple( $elm );
+ break;
+ case self::MODE_STRUCT:
+ case self::MODE_SEQ:
+ case self::MODE_BAG:
+ case self::MODE_LANG:
+ case self::MODE_BAGSTRUCT:
+ $this->endElementNested( $elm );
+ break;
+ case self::MODE_INITIAL:
+ if ( $elm === self::NS_RDF . ' Description' ) {
+ array_shift( $this->mode );
+ } else {
+ throw new MWException( 'Element ended unexpectedly while in MODE_INITIAL' );
+ }
+ break;
+ case self::MODE_LI:
+ case self::MODE_LI_LANG:
+ $this->endElementModeLi( $elm );
+ break;
+ case self::MODE_QDESC:
+ $this->endElementModeQDesc( $elm );
+ break;
+ default:
+ wfDebugLog( 'XMP', __METHOD__ . " no mode (elm = $elm)" );
+ break;
+ }
+ }
+
+ /**
+ * Hit an opening element while in MODE_IGNORE
+ *
+ * XMP is extensible, so ignore any tag we don't understand.
+ *
+ * Mostly ignores, unless we encounter the element that we are ignoring.
+ * in which case we add it to the item stack, so we can ignore things
+ * that are nested, correctly.
+ *
+ * @param $elm String namespace . ' ' . tag name
+ */
+ private function startElementModeIgnore( $elm ) {
+ if ( $elm === $this->curItem[0] ) {
+ array_unshift( $this->curItem, $elm );
+ array_unshift( $this->mode, self::MODE_IGNORE );
+ }
+ }
+
+ /**
+ * Start element in MODE_BAG (unordered array)
+ * this should always be <rdf:Bag>
+ *
+ * @param $elm String namespace . ' ' . tag
+ * @throws MWException if we have an element that's not <rdf:Bag>
+ */
+ private function startElementModeBag( $elm ) {
+ if ( $elm === self::NS_RDF . ' Bag' ) {
+ array_unshift( $this->mode, self::MODE_LI );
+ } else {
+ throw new MWException( "Expected <rdf:Bag> but got $elm." );
+ }
+
+ }
+
+ /**
+ * Start element in MODE_SEQ (ordered array)
+ * this should always be <rdf:Seq>
+ *
+ * @param $elm String namespace . ' ' . tag
+ * @throws MWException if we have an element that's not <rdf:Seq>
+ */
+ private function startElementModeSeq( $elm ) {
+ if ( $elm === self::NS_RDF . ' Seq' ) {
+ array_unshift( $this->mode, self::MODE_LI );
+ } elseif ( $elm === self::NS_RDF . ' Bag' ) {
+ # bug 27105
+ wfDebugLog( 'XMP', __METHOD__ . ' Expected an rdf:Seq, but got an rdf:Bag. Pretending'
+ . ' it is a Seq, since some buggy software is known to screw this up.' );
+ array_unshift( $this->mode, self::MODE_LI );
+ } else {
+ throw new MWException( "Expected <rdf:Seq> but got $elm." );
+ }
+
+ }
+
+ /**
+ * Start element in MODE_LANG (language alternative)
+ * this should always be <rdf:Alt>
+ *
+ * This tag tends to be used for metadata like describe this
+ * picture, which can be translated into multiple languages.
+ *
+ * XMP supports non-linguistic alternative selections,
+ * which are really only used for thumbnails, which
+ * we don't care about.
+ *
+ * @param $elm String namespace . ' ' . tag
+ * @throws MWException if we have an element that's not <rdf:Alt>
+ */
+ private function startElementModeLang( $elm ) {
+ if ( $elm === self::NS_RDF . ' Alt' ) {
+ array_unshift( $this->mode, self::MODE_LI_LANG );
+ } else {
+ throw new MWException( "Expected <rdf:Seq> but got $elm." );
+ }
+
+ }
+
+ /**
+ * Handle an opening element when in MODE_SIMPLE
+ *
+ * This should not happen often. This is for if a simple element
+ * already opened has a child element. Could happen for a
+ * qualified element.
+ *
+ * For example:
+ * <exif:DigitalZoomRatio><rdf:Description><rdf:value>0/10</rdf:value>
+ * <foo:someQualifier>Bar</foo:someQualifier> </rdf:Description>
+ * </exif:DigitalZoomRatio>
+ *
+ * This method is called when processing the <rdf:Description> element
+ *
+ * @param $elm String namespace and tag names separated by space.
+ * @param $attribs Array Attributes of the element.
+ */
+ private function startElementModeSimple( $elm, $attribs ) {
+ if ( $elm === self::NS_RDF . ' Description' ) {
+ // If this value has qualifiers
+ array_unshift( $this->mode, self::MODE_QDESC );
+ array_unshift( $this->curItem, $this->curItem[0] );
+
+ if ( isset( $attribs[self::NS_RDF . ' value'] ) ) {
+ list( $ns, $tag ) = explode( ' ', $this->curItem[0], 2 );
+ $this->saveValue( $ns, $tag, $attribs[self::NS_RDF . ' value'] );
+ }
+ } elseif ( $elm === self::NS_RDF . ' value' ) {
+ // This should not be here.
+ throw new MWException( __METHOD__ . ' Encountered <rdf:value> where it was unexpected.' );
+
+ } else {
+ // something else we don't recognize, like a qualifier maybe.
+ wfDebugLog( 'XMP', __METHOD__ . " Encountered element <$elm> where only expecting character data as value of " . $this->curItem[0] );
+ array_unshift( $this->mode, self::MODE_IGNORE );
+ array_unshift( $this->curItem, $elm );
+
+ }
+
+ }
+
+ /**
+ * Start an element when in MODE_QDESC.
+ * This generally happens when a simple element has an inner
+ * rdf:Description to hold qualifier elements.
+ *
+ * For example in:
+ * <exif:DigitalZoomRatio><rdf:Description><rdf:value>0/10</rdf:value>
+ * <foo:someQualifier>Bar</foo:someQualifier> </rdf:Description>
+ * </exif:DigitalZoomRatio>
+ * Called when processing the <rdf:value> or <foo:someQualifier>.
+ *
+ * @param $elm String namespace and tag name separated by a space.
+ *
+ */
+ private function startElementModeQDesc( $elm ) {
+ if ( $elm === self::NS_RDF . ' value' ) {
+ return; // do nothing
+ } else {
+ // otherwise its a qualifier, which we ignore
+ array_unshift( $this->mode, self::MODE_IGNORE );
+ array_unshift( $this->curItem, $elm );
+ }
+ }
+
+ /**
+ * Starting an element when in MODE_INITIAL
+ * This usually happens when we hit an element inside
+ * the outer rdf:Description
+ *
+ * This is generally where most properties start.
+ *
+ * @param $ns String Namespace
+ * @param $tag String tag name (without namespace prefix)
+ * @param $attribs Array array of attributes
+ */
+ private function startElementModeInitial( $ns, $tag, $attribs ) {
+ if ( $ns !== self::NS_RDF ) {
+
+ if ( isset( $this->items[$ns][$tag] ) ) {
+ if ( isset( $this->items[$ns][$tag]['structPart'] ) ) {
+ // If this element is supposed to appear only as
+ // a child of a structure, but appears here (not as
+ // a child of a struct), then something weird is
+ // happening, so ignore this element and its children.
+
+ wfDebugLog( 'XMP', "Encountered <$ns:$tag> outside"
+ . " of its expected parent. Ignoring." );
+
+ array_unshift( $this->mode, self::MODE_IGNORE );
+ array_unshift( $this->curItem, $ns . ' ' . $tag );
+ return;
+ }
+ $mode = $this->items[$ns][$tag]['mode'];
+ array_unshift( $this->mode, $mode );
+ array_unshift( $this->curItem, $ns . ' ' . $tag );
+ if ( $mode === self::MODE_STRUCT ) {
+ $this->ancestorStruct = isset( $this->items[$ns][$tag]['map_name'] )
+ ? $this->items[$ns][$tag]['map_name'] : $tag;
+ }
+ if ( $this->charContent !== false ) {
+ // Something weird.
+ // Should not happen in valid XMP.
+ throw new MWException( 'tag nested in non-whitespace characters.' );
+ }
+ } else {
+ // This element is not on our list of allowed elements so ignore.
+ wfDebugLog( 'XMP', __METHOD__ . " Ignoring unrecognized element <$ns:$tag>." );
+ array_unshift( $this->mode, self::MODE_IGNORE );
+ array_unshift( $this->curItem, $ns . ' ' . $tag );
+ return;
+ }
+
+ }
+ // process attributes
+ $this->doAttribs( $attribs );
+ }
+
+ /**
+ * Hit an opening element when in a Struct (MODE_STRUCT)
+ * This is generally for fields of a compound property.
+ *
+ * Example of a struct (abbreviated; flash has more properties):
+ *
+ * <exif:Flash> <rdf:Description> <exif:Fired>True</exif:Fired>
+ * <exif:Mode>1</exif:Mode></rdf:Description></exif:Flash>
+ *
+ * or:
+ *
+ * <exif:Flash rdf:parseType='Resource'> <exif:Fired>True</exif:Fired>
+ * <exif:Mode>1</exif:Mode></exif:Flash>
+ *
+ * @param $ns String namespace
+ * @param $tag String tag name (no ns)
+ * @param $attribs Array array of attribs w/ values.
+ */
+ private function startElementModeStruct( $ns, $tag, $attribs ) {
+ if ( $ns !== self::NS_RDF ) {
+
+ if ( isset( $this->items[$ns][$tag] ) ) {
+ if ( isset( $this->items[$ns][$this->ancestorStruct]['children'] )
+ && !isset( $this->items[$ns][$this->ancestorStruct]['children'][$tag] ) )
+ {
+ // This assumes that we don't have inter-namespace nesting
+ // which we don't in all the properties we're interested in.
+ throw new MWException( " <$tag> appeared nested in <" . $this->ancestorStruct
+ . "> where it is not allowed." );
+ }
+ array_unshift( $this->mode, $this->items[$ns][$tag]['mode'] );
+ array_unshift( $this->curItem, $ns . ' ' . $tag );
+ if ( $this->charContent !== false ) {
+ // Something weird.
+ // Should not happen in valid XMP.
+ throw new MWException( "tag <$tag> nested in non-whitespace characters (" . $this->charContent . ")." );
+ }
+ } else {
+ array_unshift( $this->mode, self::MODE_IGNORE );
+ array_unshift( $this->curItem, $elm );
+ return;
+ }
+
+ }
+
+ if ( $ns === self::NS_RDF && $tag === 'Description' ) {
+ $this->doAttribs( $attribs );
+ array_unshift( $this->mode, self::MODE_STRUCT );
+ array_unshift( $this->curItem, $this->curItem[0] );
+ }
+ }
+
+ /**
+ * opening element in MODE_LI
+ * process elements of arrays.
+ *
+ * Example:
+ * <exif:ISOSpeedRatings> <rdf:Seq> <rdf:li>64</rdf:li>
+ * </rdf:Seq> </exif:ISOSpeedRatings>
+ * This method is called when we hit the <rdf:li> element.
+ *
+ * @param $elm String: namespace . ' ' . tagname
+ * @param $attribs Array: Attributes. (needed for BAGSTRUCTS)
+ * @throws MWException if gets a tag other than <rdf:li>
+ */
+ private function startElementModeLi( $elm, $attribs ) {
+ if ( ( $elm ) !== self::NS_RDF . ' li' ) {
+ throw new MWException( "<rdf:li> expected but got $elm." );
+ }
+
+ if ( !isset( $this->mode[1] ) ) {
+ // This should never ever ever happen. Checking for it
+ // to be paranoid.
+ throw new MWException( 'In mode Li, but no 2xPrevious mode!' );
+ }
+
+ if ( $this->mode[1] === self::MODE_BAGSTRUCT ) {
+ // This list item contains a compound (STRUCT) value.
+ array_unshift( $this->mode, self::MODE_STRUCT );
+ array_unshift( $this->curItem, $elm );
+ $this->processingArray = true;
+
+ if ( !isset( $this->curItem[1] ) ) {
+ // be paranoid.
+ throw new MWException( 'Can not find parent of BAGSTRUCT.' );
+ }
+ list( $curNS, $curTag ) = explode( ' ', $this->curItem[1] );
+ $this->ancestorStruct = isset( $this->items[$curNS][$curTag]['map_name'] )
+ ? $this->items[$curNS][$curTag]['map_name'] : $curTag;
+
+ $this->doAttribs( $attribs );
+
+ } else {
+ // Normal BAG or SEQ containing simple values.
+ array_unshift( $this->mode, self::MODE_SIMPLE );
+ // need to add curItem[0] on again since one is for the specific item
+ // and one is for the entire group.
+ array_unshift( $this->curItem, $this->curItem[0] );
+ $this->processingArray = true;
+ }
+
+ }
+
+ /**
+ * Opening element in MODE_LI_LANG.
+ * process elements of language alternatives
+ *
+ * Example:
+ * <dc:title> <rdf:Alt> <rdf:li xml:lang="x-default">My house
+ * </rdf:li> </rdf:Alt> </dc:title>
+ *
+ * This method is called when we hit the <rdf:li> element.
+ *
+ * @param $elm String namespace . ' ' . tag
+ * @param $attribs array array of elements (most importantly xml:lang)
+ * @throws MWException if gets a tag other than <rdf:li> or if no xml:lang
+ */
+ private function startElementModeLiLang( $elm, $attribs ) {
+ if ( $elm !== self::NS_RDF . ' li' ) {
+ throw new MWException( __METHOD__ . " <rdf:li> expected but got $elm." );
+ }
+ if ( !isset( $attribs[ self::NS_XML . ' lang'] )
+ || !preg_match( '/^[-A-Za-z0-9]{2,}$/D', $attribs[ self::NS_XML . ' lang' ] ) )
+ {
+ throw new MWException( __METHOD__
+ . " <rdf:li> did not contain, or has invalid xml:lang attribute in lang alternative" );
+ }
+
+ // Lang is case-insensitive.
+ $this->itemLang = strtolower( $attribs[ self::NS_XML . ' lang' ] );
+
+ // need to add curItem[0] on again since one is for the specific item
+ // and one is for the entire group.
+ array_unshift( $this->curItem, $this->curItem[0] );
+ array_unshift( $this->mode, self::MODE_SIMPLE );
+ $this->processingArray = true;
+ }
+
+ /**
+ * Hits an opening element.
+ * Generally just calls a helper based on what MODE we're in.
+ * Also does some initial set up for the wrapper element
+ *
+ * @param $parser XMLParser
+ * @param $elm String namespace <space> element
+ * @param $attribs Array attribute name => value
+ */
+ function startElement( $parser, $elm, $attribs ) {
+
+ if ( $elm === self::NS_RDF . ' RDF'
+ || $elm === 'adobe:ns:meta/ xmpmeta'
+ || $elm === 'adobe:ns:meta/ xapmeta')
+ {
+ /* ignore. */
+ return;
+ } elseif ( $elm === self::NS_RDF . ' Description' ) {
+ if ( count( $this->mode ) === 0 ) {
+ // outer rdf:desc
+ array_unshift( $this->mode, self::MODE_INITIAL );
+ }
+ } elseif ( $elm === self::NS_RDF . ' type' ) {
+ // This doesn't support rdf:type properly.
+ // In practise I have yet to see a file that
+ // uses this element, however it is mentioned
+ // on page 25 of part 1 of the xmp standard.
+ //
+ // also it seems as if exiv2 and exiftool do not support
+ // this either (That or I misunderstand the standard)
+ wfDebugLog( 'XMP', __METHOD__ . ' Encountered <rdf:type> which isn\'t currently supported' );
+ }
+
+ if ( strpos( $elm, ' ' ) === false ) {
+ // This probably shouldn't happen.
+ wfDebugLog( 'XMP', __METHOD__ . " Encountered <$elm> which has no namespace. Skipping." );
+ return;
+ }
+
+ list( $ns, $tag ) = explode( ' ', $elm, 2 );
+
+ if ( count( $this->mode ) === 0 ) {
+ // This should not happen.
+ throw new MWException('Error extracting XMP, '
+ . "encountered <$elm> with no mode" );
+ }
+
+ switch( $this->mode[0] ) {
+ case self::MODE_IGNORE:
+ $this->startElementModeIgnore( $elm );
+ break;
+ case self::MODE_SIMPLE:
+ $this->startElementModeSimple( $elm, $attribs );
+ break;
+ case self::MODE_INITIAL:
+ $this->startElementModeInitial( $ns, $tag, $attribs );
+ break;
+ case self::MODE_STRUCT:
+ $this->startElementModeStruct( $ns, $tag, $attribs );
+ break;
+ case self::MODE_BAG:
+ case self::MODE_BAGSTRUCT:
+ $this->startElementModeBag( $elm );
+ break;
+ case self::MODE_SEQ:
+ $this->startElementModeSeq( $elm );
+ break;
+ case self::MODE_LANG:
+ $this->startElementModeLang( $elm );
+ break;
+ case self::MODE_LI_LANG:
+ $this->startElementModeLiLang( $elm, $attribs );
+ break;
+ case self::MODE_LI:
+ $this->startElementModeLi( $elm, $attribs );
+ break;
+ case self::MODE_QDESC:
+ $this->startElementModeQDesc( $elm );
+ break;
+ default:
+ throw new MWException( 'StartElement in unknown mode: ' . $this->mode[0] );
+ break;
+ }
+ }
+
+ /**
+ * Process attributes.
+ * Simple values can be stored as either a tag or attribute
+ *
+ * Often the initial <rdf:Description> tag just has all the simple
+ * properties as attributes.
+ *
+ * Example:
+ * <rdf:Description rdf:about="" xmlns:exif="http://ns.adobe.com/exif/1.0/" exif:DigitalZoomRatio="0/10">
+ *
+ * @param $attribs Array attribute=>value array.
+ */
+ private function doAttribs( $attribs ) {
+
+ // first check for rdf:parseType attribute, as that can change
+ // how the attributes are interperted.
+
+ if ( isset( $attribs[self::NS_RDF . ' parseType'] )
+ && $attribs[self::NS_RDF . ' parseType'] === 'Resource'
+ && $this->mode[0] === self::MODE_SIMPLE )
+ {
+ // this is equivalent to having an inner rdf:Description
+ $this->mode[0] = self::MODE_QDESC;
+ }
+ foreach ( $attribs as $name => $val ) {
+
+
+ if ( strpos( $name, ' ' ) === false ) {
+ // This shouldn't happen, but so far some old software forgets namespace
+ // on rdf:about.
+ wfDebugLog( 'XMP', __METHOD__ . ' Encountered non-namespaced attribute: '
+ . " $name=\"$val\". Skipping. " );
+ continue;
+ }
+ list( $ns, $tag ) = explode( ' ', $name, 2 );
+ if ( $ns === self::NS_RDF ) {
+ if ( $tag === 'value' || $tag === 'resource' ) {
+ // resource is for url.
+ // value attribute is a weird way of just putting the contents.
+ $this->char( $this->xmlParser, $val );
+ }
+ } elseif ( isset( $this->items[$ns][$tag] ) ) {
+ if ( $this->mode[0] === self::MODE_SIMPLE ) {
+ throw new MWException( __METHOD__
+ . " $ns:$tag found as attribute where not allowed" );
+ }
+ $this->saveValue( $ns, $tag, $val );
+ } else {
+ wfDebugLog( 'XMP', __METHOD__ . " Ignoring unrecognized element <$ns:$tag>." );
+ }
+ }
+ }
+
+ /**
+ * Given an extracted value, save it to results array
+ *
+ * note also uses $this->ancestorStruct and
+ * $this->processingArray to determine what name to
+ * save the value under. (in addition to $tag).
+ *
+ * @param $ns String namespace of tag this is for
+ * @param $tag String tag name
+ * @param $val String value to save
+ */
+ private function saveValue( $ns, $tag, $val ) {
+
+ $info =& $this->items[$ns][$tag];
+ $finalName = isset( $info['map_name'] )
+ ? $info['map_name'] : $tag;
+ if ( isset( $info['validate'] ) ) {
+ $validate = is_array( $info['validate'] ) ? $info['validate']
+ : array( 'XMPValidate', $info['validate'] );
+
+ if ( is_callable( $validate ) ) {
+ call_user_func_array( $validate, array( $info, &$val, true ) );
+ // the reasoning behind using &$val instead of using the return value
+ // is to be consistent between here and validating structures.
+ if ( is_null( $val ) ) {
+ wfDebugLog( 'XMP', __METHOD__ . " <$ns:$tag> failed validation." );
+ return;
+ }
+ } else {
+ wfDebugLog( 'XMP', __METHOD__ . " Validation function for $finalName ("
+ . $validate[0] . '::' . $validate[1] . '()) is not callable.' );
+ }
+ }
+
+ if ( $this->ancestorStruct && $this->processingArray ) {
+ // Aka both an array and a struct. ( self::MODE_BAGSTRUCT )
+ $this->results['xmp-' . $info['map_group']][$this->ancestorStruct][][$finalName] = $val;
+ } elseif ( $this->ancestorStruct ) {
+ $this->results['xmp-' . $info['map_group']][$this->ancestorStruct][$finalName] = $val;
+ } elseif ( $this->processingArray ) {
+ if ( $this->itemLang === false ) {
+ // normal array
+ $this->results['xmp-' . $info['map_group']][$finalName][] = $val;
+ } else {
+ // lang array.
+ $this->results['xmp-' . $info['map_group']][$finalName][$this->itemLang] = $val;
+ }
+ } else {
+ $this->results['xmp-' . $info['map_group']][$finalName] = $val;
+ }
+ }
+}