diff options
Diffstat (limited to 'vendor/setasign/fpdi/src/PdfParser/Type/PdfStream.php')
| -rw-r--r-- | vendor/setasign/fpdi/src/PdfParser/Type/PdfStream.php | 326 |
1 files changed, 326 insertions, 0 deletions
diff --git a/vendor/setasign/fpdi/src/PdfParser/Type/PdfStream.php b/vendor/setasign/fpdi/src/PdfParser/Type/PdfStream.php new file mode 100644 index 0000000..6d4c5a8 --- /dev/null +++ b/vendor/setasign/fpdi/src/PdfParser/Type/PdfStream.php @@ -0,0 +1,326 @@ +<?php + +/** + * This file is part of FPDI + * + * @package setasign\Fpdi + * @copyright Copyright (c) 2020 Setasign GmbH & Co. KG (https://www.setasign.com) + * @license http://opensource.org/licenses/mit-license The MIT License + */ + +namespace setasign\Fpdi\PdfParser\Type; + +use setasign\Fpdi\PdfParser\CrossReference\CrossReferenceException; +use setasign\Fpdi\PdfParser\Filter\Ascii85; +use setasign\Fpdi\PdfParser\Filter\AsciiHex; +use setasign\Fpdi\PdfParser\Filter\FilterException; +use setasign\Fpdi\PdfParser\Filter\Flate; +use setasign\Fpdi\PdfParser\Filter\Lzw; +use setasign\Fpdi\PdfParser\PdfParser; +use setasign\Fpdi\PdfParser\PdfParserException; +use setasign\Fpdi\PdfParser\StreamReader; +use setasign\FpdiPdfParser\PdfParser\Filter\Predictor; + +/** + * Class representing a PDF stream object + */ +class PdfStream extends PdfType +{ + /** + * Parses a stream from a stream reader. + * + * @param PdfDictionary $dictionary + * @param StreamReader $reader + * @param PdfParser $parser Optional to keep backwards compatibility + * @return self + * @throws PdfTypeException + */ + public static function parse(PdfDictionary $dictionary, StreamReader $reader, PdfParser $parser = null) + { + $v = new self(); + $v->value = $dictionary; + $v->reader = $reader; + $v->parser = $parser; + + $offset = $reader->getOffset(); + + // Find the first "newline" + while (($firstByte = $reader->getByte($offset)) !== false) { + if ($firstByte !== "\n" && $firstByte !== "\r") { + $offset++; + } else { + break; + } + } + + if ($firstByte === false) { + throw new PdfTypeException( + 'Unable to parse stream data. No newline after the stream keyword found.', + PdfTypeException::NO_NEWLINE_AFTER_STREAM_KEYWORD + ); + } + + $sndByte = $reader->getByte($offset + 1); + if ($firstByte === "\n" || $firstByte === "\r") { + $offset++; + } + + if ($sndByte === "\n" && $firstByte !== "\n") { + $offset++; + } + + $reader->setOffset($offset); + // let's only save the byte-offset and read the stream only when needed + $v->stream = $reader->getPosition() + $reader->getOffset(); + + return $v; + } + + /** + * Helper method to create an instance. + * + * @param PdfDictionary $dictionary + * @param string $stream + * @return self + */ + public static function create(PdfDictionary $dictionary, $stream) + { + $v = new self(); + $v->value = $dictionary; + $v->stream = (string) $stream; + + return $v; + } + + /** + * Ensures that the passed value is a PdfStream instance. + * + * @param mixed $stream + * @return self + * @throws PdfTypeException + */ + public static function ensure($stream) + { + return PdfType::ensureType(self::class, $stream, 'Stream value expected.'); + } + + /** + * The stream or its byte-offset position. + * + * @var int|string + */ + protected $stream; + + /** + * The stream reader instance. + * + * @var StreamReader|null + */ + protected $reader; + + /** + * The PDF parser instance. + * + * @var PdfParser + */ + protected $parser; + + /** + * Get the stream data. + * + * @param bool $cache Whether cache the stream data or not. + * @return bool|string + * @throws PdfTypeException + * @throws CrossReferenceException + * @throws PdfParserException + */ + public function getStream($cache = false) + { + if (\is_int($this->stream)) { + $length = PdfDictionary::get($this->value, 'Length'); + if ($this->parser !== null) { + $length = PdfType::resolve($length, $this->parser); + } + + if (!($length instanceof PdfNumeric) || $length->value === 0) { + $this->reader->reset($this->stream, 100000); + $buffer = $this->extractStream(); + } else { + $this->reader->reset($this->stream, $length->value); + $buffer = $this->reader->getBuffer(false); + if ($this->parser !== null) { + $this->reader->reset($this->stream + strlen($buffer)); + $this->parser->getTokenizer()->clearStack(); + $token = $this->parser->readValue(); + if ($token === false || !($token instanceof PdfToken) || $token->value !== 'endstream') { + $this->reader->reset($this->stream, 100000); + $buffer = $this->extractStream(); + $this->reader->reset($this->stream + strlen($buffer)); + } + } + } + + if ($cache === false) { + return $buffer; + } + + $this->stream = $buffer; + $this->reader = null; + } + + return $this->stream; + } + + /** + * Extract the stream "manually". + * + * @return string + * @throws PdfTypeException + */ + protected function extractStream() + { + while (true) { + $buffer = $this->reader->getBuffer(false); + $length = \strpos($buffer, 'endstream'); + if ($length === false) { + if (!$this->reader->increaseLength(100000)) { + throw new PdfTypeException('Cannot extract stream.'); + } + continue; + } + break; + } + + $buffer = \substr($buffer, 0, $length); + $lastByte = \substr($buffer, -1); + + /* Check for EOL marker = + * CARRIAGE RETURN (\r) and a LINE FEED (\n) or just a LINE FEED (\n}, + * and not by a CARRIAGE RETURN (\r) alone + */ + if ($lastByte === "\n") { + $buffer = \substr($buffer, 0, -1); + + $lastByte = \substr($buffer, -1); + if ($lastByte === "\r") { + $buffer = \substr($buffer, 0, -1); + } + } + + // There are streams in the wild, which have only white signs in them but need to be parsed manually due + // to a problem encountered before (e.g. Length === 0). We should set them to empty streams to avoid problems + // in further processing (e.g. applying of filters). + if (trim($buffer) === '') { + $buffer = ''; + } + + return $buffer; + } + + /** + * Get the unfiltered stream data. + * + * @return string + * @throws FilterException + * @throws PdfParserException + */ + public function getUnfilteredStream() + { + $stream = $this->getStream(); + $filters = PdfDictionary::get($this->value, 'Filter'); + if ($filters instanceof PdfNull) { + return $stream; + } + + if ($filters instanceof PdfArray) { + $filters = $filters->value; + } else { + $filters = [$filters]; + } + + $decodeParams = PdfDictionary::get($this->value, 'DecodeParms'); + if ($decodeParams instanceof PdfArray) { + $decodeParams = $decodeParams->value; + } else { + $decodeParams = [$decodeParams]; + } + + foreach ($filters as $key => $filter) { + if (!($filter instanceof PdfName)) { + continue; + } + + $decodeParam = null; + if (isset($decodeParams[$key])) { + $decodeParam = ($decodeParams[$key] instanceof PdfDictionary ? $decodeParams[$key] : null); + } + + switch ($filter->value) { + case 'FlateDecode': + case 'Fl': + case 'LZWDecode': + case 'LZW': + if (\strpos($filter->value, 'LZW') === 0) { + $filterObject = new Lzw(); + } else { + $filterObject = new Flate(); + } + + $stream = $filterObject->decode($stream); + + if ($decodeParam instanceof PdfDictionary) { + $predictor = PdfDictionary::get($decodeParam, 'Predictor', PdfNumeric::create(1)); + if ($predictor->value !== 1) { + if (!\class_exists(Predictor::class)) { + throw new PdfParserException( + 'This PDF document makes use of features which are only implemented in the ' . + 'commercial "FPDI PDF-Parser" add-on (see https://www.setasign.com/fpdi-pdf-' . + 'parser).', + PdfParserException::IMPLEMENTED_IN_FPDI_PDF_PARSER + ); + } + + $colors = PdfDictionary::get($decodeParam, 'Colors', PdfNumeric::create(1)); + $bitsPerComponent = PdfDictionary::get( + $decodeParam, + 'BitsPerComponent', + PdfNumeric::create(8) + ); + + $columns = PdfDictionary::get($decodeParam, 'Columns', PdfNumeric::create(1)); + + $filterObject = new Predictor( + $predictor->value, + $colors->value, + $bitsPerComponent->value, + $columns->value + ); + + $stream = $filterObject->decode($stream); + } + } + + break; + case 'ASCII85Decode': + case 'A85': + $filterObject = new Ascii85(); + $stream = $filterObject->decode($stream); + break; + + case 'ASCIIHexDecode': + case 'AHx': + $filterObject = new AsciiHex(); + $stream = $filterObject->decode($stream); + break; + + default: + throw new FilterException( + \sprintf('Unsupported filter "%s".', $filter->value), + FilterException::UNSUPPORTED_FILTER + ); + } + } + + return $stream; + } +} |