/**
* Dereference.
* Take inderect object, take $value member of this object (must be Zend_Pdf_Element),
* take reference to the $value member of this object and assign it to
* $value member of current PDF Reference object
* $obj can be null
*
* @throws Zend_Pdf_Exception
*/
private function _dereference()
{
$obj = $this->_context->getParser()->getObject($this->_context->getRefTable()->getOffset($this->_objNum . ' ' . $this->_genNum . ' R'), $this->_context);
if ($obj === null) {
$this->_ref = new Zend_Pdf_Element_Null();
return;
}
if ($obj->toString() != $this->_objNum . ' ' . $this->_genNum . ' R') {
throw new Zend_Pdf_Exception('Incorrect reference to the object');
}
$this->_ref = $obj;
$this->setParentObject($obj);
$this->_factory->registerObject($this);
}
/**
* Dereference.
* Take inderect object, take $value member of this object (must be Zend_Pdf_Element),
* take reference to the $value member of this object and assign it to
* $value member of current PDF Reference object
* $obj can be null
*
* @throws Zend_Pdf_Exception
*/
private function _dereference()
{
if (($obj = $this->_factory->fetchObject($this->_objNum . ' ' . $this->_genNum)) === null) {
$obj = $this->_context->getParser()->getObject($this->_context->getRefTable()->getOffset($this->_objNum . ' ' . $this->_genNum . ' R'), $this->_context);
}
if ($obj === null) {
$this->_ref = new Zend_Pdf_Element_Null();
return;
}
if ($obj->toString() != $this->_objNum . ' ' . $this->_genNum . ' R') {
require_once 'Zend/Pdf/Exception.php';
throw new Zend_Pdf_Exception('Incorrect reference to the object');
}
$this->_ref = $obj;
}
/**
* Get header of free objects list
* Returns object number of last free object
*
* @throws Zend_Pdf_Exception
* @return integer
*/
public function getLastFreeObject()
{
try {
$this->_context->getRefTable()->getNextFree('0 65535 R');
} catch (Zend_Pdf_Exception $e) {
if ($e->getMessage() == 'Object not found.') {
/**
* Here is work around for some wrong generated PDFs.
* We have not found reference to the header of free object list,
* thus we treat it as there are no free objects.
*/
return 0;
}
throw new Zend_Pdf_Exception($e->getMessage(), $e->getCode(), $e);
}
}
/**
* Load XReference table and referenced objects
*
* @param integer $offset
* @throws Zend_Pdf_Exception
* @return Zend_Pdf_Trailer_Keeper
*/
private function _loadXRefTable($offset)
{
$this->_pushContext();
$this->_current = $offset;
$refTable = new Zend_Pdf_Element_Reference_Table();
$context = new Zend_Pdf_Element_Reference_Context($this, $refTable);
$this->_currentContext = $context;
$nextLexeme = $this->_readLexeme();
if ($nextLexeme == 'xref') {
/**
* Common cross-reference table
*/
$this->_skipWhiteSpace();
while (($nextLexeme = $this->_readLexeme()) != 'trailer') {
if (!ctype_digit($nextLexeme)) {
throw new Zend_Pdf_Exception(sprintf('PDF file syntax error. Offset - 0x%X. Cross-reference table subheader values must contain only digits.', $this->_current - strlen($nextLexeme)));
}
$objNum = (int) $nextLexeme;
$refCount = $this->_readLexeme();
if (!ctype_digit($refCount)) {
throw new Zend_Pdf_Exception(sprintf('PDF file syntax error. Offset - 0x%X. Cross-reference table subheader values must contain only digits.', $this->_current - strlen($refCount)));
}
$this->_skipWhiteSpace();
while ($refCount > 0) {
$objectOffset = substr($this->_pdfString, $this->_current, 10);
if (!ctype_digit($objectOffset)) {
throw new Zend_Pdf_Exception(sprintf('PDF file cross-reference table syntax error. Offset - 0x%X. Offset must contain only digits.', $this->_current));
}
// Force $objectOffset to be treated as decimal instead of octal number
for ($numStart = 0; $numStart < strlen($objectOffset) - 1; $numStart++) {
if ($objectOffset[$numStart] != '0') {
break;
}
}
$objectOffset = substr($objectOffset, $numStart);
$this->_current += 10;
if (!self::isWhiteSpace(ord($this->_pdfString[$this->_current]))) {
throw new Zend_Pdf_Exception(sprintf('PDF file cross-reference table syntax error. Offset - 0x%X. Value separator must be white space.', $this->_current));
}
$this->_current++;
$genNumber = substr($this->_pdfString, $this->_current, 5);
if (!ctype_digit($objectOffset)) {
throw new Zend_Pdf_Exception(sprintf('PDF file cross-reference table syntax error. Offset - 0x%X. Offset must contain only digits.', $this->_current));
}
// Force $objectOffset to be treated as decimal instead of octal number
for ($numStart = 0; $numStart < strlen($genNumber) - 1; $numStart++) {
if ($genNumber[$numStart] != '0') {
break;
}
}
$genNumber = substr($genNumber, $numStart);
$this->_current += 5;
if (!self::isWhiteSpace(ord($this->_pdfString[$this->_current]))) {
throw new Zend_Pdf_Exception(sprintf('PDF file cross-reference table syntax error. Offset - 0x%X. Value separator must be white space.', $this->_current));
}
$this->_current++;
$inUseKey = $this->_pdfString[$this->_current];
$this->_current++;
switch ($inUseKey) {
case 'f':
// free entry
unset($this->_refTable[$objNum . ' ' . $genNumber . ' R']);
$refTable->addReference($objNum . ' ' . $genNumber . ' R', $objectOffset, false);
break;
case 'n':
// in-use entry
$refTable->addReference($objNum . ' ' . $genNumber . ' R', $objectOffset, true);
}
if (!self::isWhiteSpace(ord($this->_pdfString[$this->_current]))) {
throw new Zend_Pdf_Exception(sprintf('PDF file cross-reference table syntax error. Offset - 0x%X. Value separator must be white space.', $this->_current));
}
$this->_current++;
if (!self::isWhiteSpace(ord($this->_pdfString[$this->_current]))) {
throw new Zend_Pdf_Exception(sprintf('PDF file cross-reference table syntax error. Offset - 0x%X. Value separator must be white space.', $this->_current));
}
$this->_current++;
$refCount--;
$objNum++;
}
}
$trailerDictOffset = $this->_current;
$trailerDict = $this->_readElementalObject();
if (!$trailerDict instanceof Zend_Pdf_Element_Dictionary) {
throw new Zend_Pdf_Exception(sprintf('PDF file syntax error. Offset - 0x%X. Dictionary expected after \'trailer\' keyword.', $trailerDictOffset));
}
$trailerObj = new Zend_Pdf_Trailer_Keeper($trailerDict, $context);
if ($trailerDict->Prev instanceof Zend_Pdf_Element_Numeric || $trailerDict->Prev instanceof Zend_Pdf_Element_Reference) {
$trailerObj->setPrev($this->_loadXRefTable($trailerDict->Prev->value));
$context->getRefTable()->setParent($trailerObj->getPrev()->getRefTable());
}
/**
* We set '/Prev' dictionary property to the current cross-reference section offset.
* It doesn't correspond to the actual data, but is true when trailer will be used
* as trailer for next generated PDF section.
*/
$trailerObj->Prev = new Zend_Pdf_Element_Numeric($offset);
} else {
throw new Zend_Exception(sprintf('Pdf file syntax error. Offset - 0x%X. \'xref\' lexeme expected.', $this->_current - strlen($nextLexeme)));
/**
* @todo Cross-Reference stream object must be loaded here.
*/
}
$this->_popContext();
return $trailerObj;
}
/**
* Get header of free objects list
* Returns object number of last free object
*
* @return integer
*/
public function getLastFreeObject()
{
$this->_context->getRefTable()->getNextFree('0 65535 R');
}
