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See Release Notes

  • Bug fixes for general core bugs in 4.2.x will end 22 April 2024 (12 months).
  • Bug fixes for security issues in 4.2.x will end 7 October 2024 (18 months).
  • PHP version: minimum PHP 8.0.0 Note: minimum PHP version has increased since Moodle 4.1. PHP 8.1.x is supported too.
<?php
>
/** * This file is part of FPDI * * @package setasign\Fpdi
< * @copyright Copyright (c) 2019 Setasign - Jan Slabon (https://www.setasign.com)
> * @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\CrossReference; use setasign\Fpdi\PdfParser\PdfParser; use setasign\Fpdi\PdfParser\StreamReader; /** * Class LineReader * * This reader class read all cross-reference entries in a single run. * It supports reading cross-references with e.g. invalid data (e.g. entries with a length < or > 20 bytes).
< * < * @package setasign\Fpdi\PdfParser\CrossReference
*/ class LineReader extends AbstractReader implements ReaderInterface { /** * The object offsets. * * @var array */ protected $offsets; /** * LineReader constructor. * * @param PdfParser $parser * @throws CrossReferenceException */ public function __construct(PdfParser $parser) { $this->read($this->extract($parser->getStreamReader())); parent::__construct($parser); } /** * @inheritdoc */ public function getOffsetFor($objectNumber) { if (isset($this->offsets[$objectNumber])) { return $this->offsets[$objectNumber][0]; } return false; } /** * Get all found offsets. * * @return array */ public function getOffsets() { return $this->offsets; } /** * Extracts the cross reference data from the stream reader. * * @param StreamReader $reader * @return string * @throws CrossReferenceException */ protected function extract(StreamReader $reader) {
< $cycles = -1;
$bytesPerCycle = 100;
<
$reader->reset(null, $bytesPerCycle);
< while ( < ($trailerPos = \strpos($reader->getBuffer(false), 'trailer', \max($bytesPerCycle * $cycles++, 0))) === false < ) { < if ($reader->increaseLength($bytesPerCycle) === false) { < break; < } < }
> $cycles = 0; > do { > // 6 = length of "trailer" - 1 > $pos = \max(($bytesPerCycle * $cycles) - 6, 0); > $trailerPos = \strpos($reader->getBuffer(false), 'trailer', $pos); > $cycles++; > } while ($trailerPos === false && $reader->increaseLength($bytesPerCycle) !== false);
if ($trailerPos === false) { throw new CrossReferenceException( 'Unexpected end of cross reference. "trailer"-keyword not found.', CrossReferenceException::NO_TRAILER_FOUND ); } $xrefContent = \substr($reader->getBuffer(false), 0, $trailerPos); $reader->reset($reader->getPosition() + $trailerPos); return $xrefContent; } /** * Read the cross-reference entries. * * @param string $xrefContent * @throws CrossReferenceException */ protected function read($xrefContent) { // get eol markers in the first 100 bytes \preg_match_all("/(\r\n|\n|\r)/", \substr($xrefContent, 0, 100), $m); if (\count($m[0]) === 0) { throw new CrossReferenceException( 'No data found in cross-reference.', CrossReferenceException::INVALID_DATA ); } // count(array_count_values()) is faster then count(array_unique()) // @see https://github.com/symfony/symfony/pull/23731 // can be reverted for php7.2 $differentLineEndings = \count(\array_count_values($m[0])); if ($differentLineEndings > 1) { $lines = \preg_split("/(\r\n|\n|\r)/", $xrefContent, -1, PREG_SPLIT_NO_EMPTY); } else { $lines = \explode($m[0][0], $xrefContent); } unset($differentLineEndings, $m);
< $linesCount = \count($lines); < $start = null; < $entryCount = 0;
> if (!\is_array($lines)) { > $this->offsets = []; > return; > }
> $start = 0;
$offsets = [];
< /** @noinspection ForeachInvariantsInspection */ < for ($i = 0; $i < $linesCount; $i++) { < $line = \trim($lines[$i]); < if ($line) {
> // trim all lines and remove empty lines > $lines = \array_filter(\array_map('\trim', $lines)); > foreach ($lines as $line) {
$pieces = \explode(' ', $line);
< $c = \count($pieces); < switch ($c) {
> switch (\count($pieces)) {
case 2: $start = (int) $pieces[0];
< $entryCount += (int) $pieces[1];
break;
< /** @noinspection PhpMissingBreakStatementInspection */
case 3: switch ($pieces[2]) { case 'n': $offsets[$start] = [(int) $pieces[0], (int) $pieces[1]]; $start++; break 2; case 'f': $start++; break 2; } // fall through if pieces doesn't match default: throw new CrossReferenceException( \sprintf('Unexpected data in xref table (%s)', \implode(' ', $pieces)), CrossReferenceException::INVALID_DATA );
< }
} } $this->offsets = $offsets; } }