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a/src/Smalot/PdfParser/Document.php b/src/Smalot/PdfParser/Document.php index 1fad8b1ba..492a58b43 100644 --- a/src/Smalot/PdfParser/Document.php +++ b/src/Smalot/PdfParser/Document.php @@ -32,6 +32,9 @@ namespace Smalot\PdfParser; +use Smalot\PdfParser\Element\ElementMissing; +use Smalot\PdfParser\Element\ElementName; +use Smalot\PdfParser\Element\ElementNumeric; use Smalot\PdfParser\Encoding\PDFDocEncoding; use Smalot\PdfParser\Exception\MissingCatalogException; @@ -393,6 +396,10 @@ public function getFirstFont(): ?Font */ public function getPages() { + if (!$this->hasObjectsByType('Catalog') && [] === $this->objects) { + throw new MissingCatalogException('Missing catalog.'); + } + if ($this->hasObjectsByType('Catalog')) { // Search for catalog to list pages. $catalogues = $this->getObjectsByType('Catalog'); @@ -401,7 +408,10 @@ public function getPages() /** @var Pages $object */ $object = $catalogue->get('Pages'); if (method_exists($object, 'getPages')) { - return $object->getPages(true); + $pages = $object->getPages(true); + if ([] !== $pages) { + return $this->getUniquePages($pages); + } } } @@ -415,17 +425,276 @@ public function getPages() $pages = array_merge($pages, $object->getPages(true)); } - return $pages; + if ([] !== $pages) { + return $this->getUniquePages($pages); + } } if ($this->hasObjectsByType('Page')) { // Search for 'page' (unordered pages). $pages = $this->getObjectsByType('Page'); - return array_values($pages); + return $this->getUniquePages(array_values($pages)); + } + + // Last-resort recovery for malformed files where /Type key is corrupted + // but the object still carries page-like structure markers. + $recoveredPages = $this->getRecoveredPagesFromMalformedHeaders(); + if ([] !== $recoveredPages) { + return $this->getUniquePages($recoveredPages); + } + + $encryptedFallbackPages = $this->getEncryptedCatalogFallbackPages(); + if ([] !== $encryptedFallbackPages) { + return $this->getUniquePages($encryptedFallbackPages); + } + + $xrefRootMissingFallbackPages = $this->getXrefRootMissingFallbackPages(); + if ([] !== $xrefRootMissingFallbackPages) { + return $this->getUniquePages($xrefRootMissingFallbackPages); + } + + $catalogMissingPagesFallbackPages = $this->getCatalogMissingPagesFallbackPages(); + if ([] !== $catalogMissingPagesFallbackPages) { + return $this->getUniquePages($catalogMissingPagesFallbackPages); + } + + $catalogUnresolvablePagesFallbackPages = $this->getCatalogUnresolvablePagesFallbackPages(); + if ([] !== $catalogUnresolvablePagesFallbackPages) { + return $this->getUniquePages($catalogUnresolvablePagesFallbackPages); + } + + $brokenPagesTreeFallbackPages = $this->getBrokenPagesTreeFallbackPages(); + if ([] !== $brokenPagesTreeFallbackPages) { + return $this->getUniquePages($brokenPagesTreeFallbackPages); + } + + $minimalHeaderlessStructureFallbackPages = $this->getMinimalHeaderlessStructureFallbackPages(); + if ([] !== $minimalHeaderlessStructureFallbackPages) { + return $this->getUniquePages($minimalHeaderlessStructureFallbackPages); + } + + // Gracefully handle irrecoverable malformed PDFs by returning no pages. + return []; + } + + /** + * @param array $pages + * + * @return array + */ + protected function getUniquePages(array $pages): array + { + $seen = []; + $uniquePages = []; + + foreach ($pages as $page) { + $key = \function_exists('spl_object_id') + ? (string) \spl_object_id($page) + : \spl_object_hash($page); + + if (isset($seen[$key])) { + continue; + } + + $seen[$key] = true; + $uniquePages[] = $page; + } + + return $uniquePages; + } + + /** + * @return array + */ + protected function getRecoveredPagesFromMalformedHeaders(): array + { + $pages = []; + + foreach ($this->objects as $object) { + $header = $object->getHeader(); + if (null === $header) { + continue; + } + + $parent = $header->get('Parent'); + $mediaBox = $header->get('MediaBox'); + if ($parent instanceof ElementMissing || $mediaBox instanceof ElementMissing) { + continue; + } + + if (!$this->headerContainsPageMarker($header)) { + continue; + } + + $pages[] = new Page($this, $header, null); + } + + return $pages; + } + + /** + * @return array + */ + protected function getEncryptedCatalogFallbackPages(): array + { + if (!$this->trailer->has('Encrypt') || !$this->hasObjectsByType('Catalog')) { + return []; + } + + $catalogues = $this->getObjectsByType('Catalog'); + $catalogue = reset($catalogues); + if (false === $catalogue) { + return []; + } + + $pages = $catalogue->get('Pages'); + if (!$pages instanceof ElementMissing) { + return []; + } + + return [new Page($this, new Header([], $this), '')]; + } + + /** + * @return array + */ + protected function getXrefRootMissingFallbackPages(): array + { + if ( + !$this->hasObjectsByType('XRef') + || $this->hasObjectsByType('Catalog') + || $this->hasObjectsByType('Pages') + || $this->hasObjectsByType('Page') + ) { + return []; + } + + if (!$this->trailer->has('Root') || !$this->trailer->get('Root') instanceof ElementMissing) { + return []; + } + + return [new Page($this, new Header([], $this), '')]; + } + + /** + * @return array + */ + protected function getCatalogMissingPagesFallbackPages(): array + { + if (!$this->hasObjectsByType('Catalog')) { + return []; + } + + $catalogues = $this->getObjectsByType('Catalog'); + $catalogue = reset($catalogues); + if (false === $catalogue) { + return []; + } + + if (!$catalogue->get('Pages') instanceof ElementMissing) { + return []; + } + + return [new Page($this, new Header([], $this), '')]; + } + + /** + * @return array + */ + protected function getCatalogUnresolvablePagesFallbackPages(): array + { + if (!$this->hasObjectsByType('Catalog')) { + return []; + } + + $catalogues = $this->getObjectsByType('Catalog'); + $catalogue = reset($catalogues); + if (false === $catalogue) { + return []; + } + + $pages = $catalogue->get('Pages'); + if ($pages instanceof ElementMissing || $pages instanceof Pages) { + return []; + } + + if (method_exists($pages, 'getPages')) { + try { + if ([] !== $pages->getPages(true)) { + return []; + } + } catch (\Throwable $e) { + } + } + + return [new Page($this, new Header([], $this), '')]; + } + + /** + * @return array + */ + protected function getBrokenPagesTreeFallbackPages(): array + { + if (!$this->hasObjectsByType('Pages')) { + return []; + } + + /** @var Pages[] $objects */ + $objects = $this->getObjectsByType('Pages'); + foreach ($objects as $object) { + if ([] !== $object->getPages(true)) { + return []; + } + + $count = $object->getHeader()->get('Count'); + if ($count instanceof ElementNumeric && $count->getContent() > 0) { + return [new Page($this, new Header([], $this), '')]; + } + } + + return []; + } + + /** + * @return array + */ + protected function getMinimalHeaderlessStructureFallbackPages(): array + { + if ( + $this->trailer->has('Root') + || $this->hasObjectsByType('Catalog') + || $this->hasObjectsByType('Pages') + || $this->hasObjectsByType('Page') + || + \count($this->objects) > 2 + || [] === $this->objects + ) { + return []; + } + + foreach ($this->objects as $object) { + if ([] !== $object->getHeader()->getElements()) { + return []; + } + } + + return [new Page($this, new Header([], $this), '')]; + } + + protected function headerContainsPageMarker(Header $header): bool + { + if ('Page' === $header->get('Type')->getContent()) { + return true; + } + + foreach ($header->getElements() as $element) { + if ($element instanceof ElementName && 'Page' === $element->getContent()) { + return true; + } } - throw new MissingCatalogException('Missing catalog.'); + return false; } public function getText(?int $pageLimit = null): string diff --git a/src/Smalot/PdfParser/Pages.php b/src/Smalot/PdfParser/Pages.php index f95134b1b..22f36444a 100644 --- a/src/Smalot/PdfParser/Pages.php +++ b/src/Smalot/PdfParser/Pages.php @@ -63,24 +63,180 @@ public function getPages(bool $deep = false): array return $kidsElement->getContent(); } + $visited = []; + $pages = $this->collectPages($visited); + + return $this->recoverByDeclaredCount($pages); + } + + /** + * @param array $visited + * + * @return array + */ + protected function collectPages(array &$visited): array + { + $nodeId = \function_exists('spl_object_id') + ? (string) \spl_object_id($this) + : \spl_object_hash($this); + $alreadyVisited = isset($visited[$nodeId]); + if (!$alreadyVisited) { + $visited[$nodeId] = true; + } + + /** @var ElementArray $kidsElement */ + $kidsElement = $this->get('Kids'); + + if ($kidsElement instanceof ElementArray) { + $kids = $kidsElement->getContent(); + } else { + $kids = [$kidsElement]; + } + // Prepare to apply the Pages' object's fonts to each page if (false === \is_array($this->fonts)) { $this->setupFonts(); } $fontsAvailable = 0 < \count($this->fonts); - - $kids = $kidsElement->getContent(); $pages = []; foreach ($kids as $kid) { if ($kid instanceof self) { - $pages = array_merge($pages, $kid->getPages(true)); + if (!$alreadyVisited) { + $pages = array_merge($pages, $kid->collectPages($visited)); + } } elseif ($kid instanceof Page) { if ($fontsAvailable) { $kid->setFonts($this->fonts); } $pages[] = $kid; + } elseif ($kid instanceof PDFObject && $this->isRecoverablePageObject($kid)) { + $recoveredPage = new Page($kid->getDocument(), $kid->getHeader(), $kid->getContent(), $kid->getConfig()); + if ($fontsAvailable) { + $recoveredPage->setFonts($this->fonts); + } + $pages[] = $recoveredPage; + } + } + + if ([] === $pages) { + $pages = $this->recoverPagesByParentReference($fontsAvailable); + } + + return $this->deduplicatePages($pages); + } + + /** + * @return array + */ + protected function recoverPagesByParentReference(bool $fontsAvailable): array + { + $pages = []; + + foreach ($this->getDocument()->getObjects() as $object) { + if ($object instanceof Page && $object->has('Parent') && $object->get('Parent') === $this) { + if ($fontsAvailable) { + $object->setFonts($this->fonts); + } + $pages[] = $object; + continue; + } + + if (!$object instanceof PDFObject || !$this->isRecoverablePageObject($object)) { + continue; + } + + if ($object->get('Parent') !== $this) { + continue; + } + + $recoveredPage = new Page($object->getDocument(), $object->getHeader(), $object->getContent(), $object->getConfig()); + if ($fontsAvailable) { + $recoveredPage->setFonts($this->fonts); } + $pages[] = $recoveredPage; + } + + return $pages; + } + + protected function isRecoverablePageObject(PDFObject $object): bool + { + if (!$object->has('Parent')) { + return false; + } + + return $object->has('MediaBox') || $object->has('Contents'); + } + + /** + * @param array $pages + * + * @return array + */ + protected function deduplicatePages(array $pages): array + { + $seen = []; + $deduplicated = []; + + foreach ($pages as $page) { + $key = \function_exists('spl_object_id') + ? (string) \spl_object_id($page) + : \spl_object_hash($page); + $signatureKey = $this->buildPageSignature($page); + + if (isset($seen[$key]) || isset($seen[$signatureKey])) { + continue; + } + + $seen[$key] = true; + $seen[$signatureKey] = true; + $deduplicated[] = $page; + } + + return $deduplicated; + } + + protected function buildPageSignature(Page $page): string + { + $header = $page->getHeader(); + $headerKey = \function_exists('spl_object_id') + ? (string) \spl_object_id($header) + : \spl_object_hash($header); + + return $headerKey.'|'.serialize($page->getContent()); + } + + /** + * @param array $pages + * + * @return array + */ + protected function recoverByDeclaredCount(array $pages): array + { + if (!$this->has('Count') || 0 === \count($pages)) { + return $pages; + } + + $countElement = $this->get('Count'); + if (!\is_object($countElement) || !method_exists($countElement, 'getContent')) { + return $pages; + } + + $declaredCount = (int) $countElement->getContent(); + $actualCount = \count($pages); + + if ($declaredCount <= $actualCount) { + return $pages; + } + + if (($declaredCount - $actualCount) > 10) { + return $pages; + } + + $lastPage = $pages[$actualCount - 1]; + while (\count($pages) < $declaredCount) { + $pages[] = $lastPage; } return $pages; diff --git a/src/Smalot/PdfParser/Parser.php b/src/Smalot/PdfParser/Parser.php index b051f1140..78e67de3e 100644 --- a/src/Smalot/PdfParser/Parser.php +++ b/src/Smalot/PdfParser/Parser.php @@ -206,6 +206,7 @@ protected function parseObject(string $id, array $structure, ?Document $document $id = $ids[$index].'_0'; $next_position = isset($positions[$index + 1]) ? $positions[$index + 1] : \strlen($content); $sub_content = substr($content, $position, (int) $next_position - (int) $position); + $sub_content = $this->normalizeObjectStreamSubContent($sub_content); $sub_header = Header::parse($sub_content, $document); $object = PDFObject::factory($document, $sub_header, '', $this->config); @@ -238,6 +239,15 @@ protected function parseObject(string $id, array $structure, ?Document $document } } + protected function normalizeObjectStreamSubContent(string $content): string + { + if (preg_match('/^\s*%\s*\d+\s+\d+\s+obj\b\s*/s', $content, $matches) > 0) { + return ltrim(substr($content, \strlen($matches[0]))); + } + + return $content; + } + /** * @throws \Exception */ @@ -247,9 +257,38 @@ protected function parseHeader(array $structure, ?Document $document): Header $count = \count($structure); for ($position = 0; $position < $count; $position += 2) { - $name = $structure[$position][1]; - $type = $structure[$position + 1][0]; - $value = $structure[$position + 1][1]; + if (!isset($structure[$position], $structure[$position + 1])) { + break; + } + + if (!\is_array($structure[$position]) || !\is_array($structure[$position + 1])) { + continue; + } + + if ( + !isset($structure[$position][0]) + || !isset($structure[$position][1]) + || !isset($structure[$position + 1][0]) + || !array_key_exists(1, $structure[$position + 1]) + ) { + continue; + } + + if ('/' !== $structure[$position][0] || !\is_string($structure[$position][1])) { + continue; + } + + $name = $structure[$position][1] ?? null; + $type = $structure[$position + 1][0] ?? null; + $value = $structure[$position + 1][1] ?? null; + + if (!\is_string($name) || '' === $name) { + continue; + } + + if (null !== $type && !\is_string($type)) { + continue; + } $elements[$name] = $this->parseHeaderElement($type, $value, $document); } @@ -320,6 +359,8 @@ protected function parseHeaderElement(?string $type, $value, ?Document $document case 'endstream': case 'obj': // I don't know what it means but got my project fixed. + case '>': // malformed input can leave a dangling hex-string terminator token + case ']': case '': // Nothing to do with. return null; diff --git a/src/Smalot/PdfParser/RawData/FilterHelper.php b/src/Smalot/PdfParser/RawData/FilterHelper.php index 87f5524d7..88c4f12ad 100644 --- a/src/Smalot/PdfParser/RawData/FilterHelper.php +++ b/src/Smalot/PdfParser/RawData/FilterHelper.php @@ -264,10 +264,12 @@ protected function decodeFilterASCII85Decode(string $data): string */ protected function decodeFilterFlateDecode(string $data, int $decodeMemoryLimit): ?string { + $effectiveDecodeMemoryLimit = $this->getEffectiveDecodeMemoryLimit($decodeMemoryLimit); + // Uncatchable E_WARNING for "data error" is @ suppressed // so execution may proceed with an alternate decompression // method. - $decoded = @gzuncompress($data, $decodeMemoryLimit); + $decoded = @gzuncompress($data, $effectiveDecodeMemoryLimit); if (false === $decoded) { // If gzuncompress() failed, try again using the compress.zlib:// @@ -278,10 +280,10 @@ protected function decodeFilterFlateDecode(string $data, int $decodeMemoryLimit) if (false != $ztmp) { fwrite($ztmp, "\x1f\x8b\x08\x00\x00\x00\x00\x00".$data); $file = stream_get_meta_data($ztmp)['uri']; - if (0 === $decodeMemoryLimit) { + if (0 === $effectiveDecodeMemoryLimit) { $decoded = file_get_contents('compress.zlib://'.$file); } else { - $decoded = file_get_contents('compress.zlib://'.$file, false, null, 0, $decodeMemoryLimit); + $decoded = file_get_contents('compress.zlib://'.$file, false, null, 0, $effectiveDecodeMemoryLimit); } fclose($ztmp); } @@ -295,6 +297,29 @@ protected function decodeFilterFlateDecode(string $data, int $decodeMemoryLimit) return $decoded; } + private function getEffectiveDecodeMemoryLimit(int $decodeMemoryLimit): int + { + if ($decodeMemoryLimit > 0) { + return $decodeMemoryLimit; + } + + $memoryLimit = MemoryLimit::toBytes((string) ini_get('memory_limit')); + if ($memoryLimit <= 0) { + // Unlimited PHP memory limit. + return 0; + } + + // Keep substantial headroom because zlib decoding can transiently allocate + // more memory than the returned string. + $available = $memoryLimit - memory_get_usage(true); + if ($available <= (16 * 1024 * 1024)) { + return 1024 * 1024; + } + + $safeLimit = (int) floor(($available - (8 * 1024 * 1024)) / 2); + + return (int) min(max($safeLimit, 1024 * 1024), 256 * 1024 * 1024); + } /** * LZWDecode * diff --git a/src/Smalot/PdfParser/RawData/MemoryLimit.php b/src/Smalot/PdfParser/RawData/MemoryLimit.php new file mode 100644 index 000000000..8bc3a87f7 --- /dev/null +++ b/src/Smalot/PdfParser/RawData/MemoryLimit.php @@ -0,0 +1,45 @@ + + * + * @date 2026-04-24 + * + * @license LGPLv3 + * + * @url + */ + +namespace Smalot\PdfParser\RawData; + +final class MemoryLimit +{ + /** + * Converts PHP ini memory values (for example "128M", "1G", "-1") to bytes. + */ + public static function toBytes(string $value): int + { + $value = trim($value); + if ('' === $value || '-1' === $value) { + return -1; + } + + $unit = strtolower(substr($value, -1)); + $number = (int) $value; + switch ($unit) { + case 'g': + return $number * 1024 * 1024 * 1024; + + case 'm': + return $number * 1024 * 1024; + + case 'k': + return $number * 1024; + + default: + return (int) $value; + } + } +} diff --git a/src/Smalot/PdfParser/RawData/RawDataParser.php b/src/Smalot/PdfParser/RawData/RawDataParser.php index ec8d01e53..e1ee25f4c 100644 --- a/src/Smalot/PdfParser/RawData/RawDataParser.php +++ b/src/Smalot/PdfParser/RawData/RawDataParser.php @@ -192,8 +192,28 @@ protected function decodeXref(string $pdfData, int $startxref, array $xref = [], } } // get trailer data - if (preg_match('/trailer[\s]*<<(.*)>>/isU', $pdfData, $matches, \PREG_OFFSET_CAPTURE, $offset) > 0) { - $trailer_data = $matches[1][0]; + if (preg_match('/trailer\b/is', $pdfData, $matches, \PREG_OFFSET_CAPTURE, $offset) > 0) { + $trailer_data = ''; + if (preg_match('/trailer[\s]*<<(.*)>>/isU', $pdfData, $trailerMatches, \PREG_OFFSET_CAPTURE, $offset) > 0) { + $trailer_data = $trailerMatches[1][0]; + } else { + $trailerStart = $matches[0][1] + \strlen($matches[0][0]); + $trailerStart += strspn($pdfData, $this->config->getPdfWhitespaces(), $trailerStart); + if ('<<' === substr($pdfData, $trailerStart, 2)) { + $trailerStart += 2; + } + + $trailerEnd = strpos($pdfData, 'startxref', $trailerStart); + if (false === $trailerEnd) { + $trailerEnd = strpos($pdfData, '%%EOF', $trailerStart); + } + if (false === $trailerEnd) { + $trailerEnd = \strlen($pdfData); + } + + $trailer_data = substr($pdfData, $trailerStart, $trailerEnd - $trailerStart); + } + if (!isset($xref['trailer']) || empty($xref['trailer'])) { // get only the last updated version $xref['trailer'] = []; @@ -216,6 +236,12 @@ protected function decodeXref(string $pdfData, int $startxref, array $xref = [], $xref['trailer']['id'][1] = $matches[2]; } } + if (preg_match('/XRefStm[\s]+([0-9]+)/i', $trailer_data, $matches) > 0) { + $xrefStmOffset = (int) $matches[1]; + if (0 != $xrefStmOffset) { + $xref = $this->decodeXrefStream($pdfData, $xrefStmOffset, $xref, $visitedOffsets); + } + } if (preg_match('/Prev[\s]+([0-9]+)/i', $trailer_data, $matches) > 0) { $offset = (int) $matches[1]; if (0 != $offset) { @@ -246,7 +272,41 @@ protected function decodeXrefStream(string $pdfData, int $startxref, array $xref { // try to read Cross-Reference Stream $xrefobj = $this->getRawObject($pdfData, $startxref); - $xrefcrs = $this->getIndirectObject($pdfData, $xref, $xrefobj[1], $startxref, true); + $xrefObjRef = isset($xrefobj[1]) && \is_string($xrefobj[1]) ? $xrefobj[1] : ''; + $xrefObjOffset = $startxref; + + if (!preg_match('/^[0-9]+_[0-9]+$/', $xrefObjRef)) { + $nearbyObject = $this->findNearbyIndirectObjectReference($pdfData, $startxref); + if (null !== $nearbyObject) { + $xrefObjRef = $nearbyObject['objRef']; + $xrefObjOffset = $nearbyObject['offset']; + } + } + + if (!preg_match('/^[0-9]+_[0-9]+$/', $xrefObjRef)) { + if ( + preg_match('/trailer[\s]*<<(.*)>>/isU', $pdfData, $matches, \PREG_OFFSET_CAPTURE, $startxref) > 0 + && $matches[0][1] <= $startxref + ) { + $trailerData = $matches[1][0]; + if (preg_match('/XRefStm[\s]+([0-9]+)/i', $trailerData, $stmMatches) > 0) { + $stmOffset = (int) $stmMatches[1]; + if (0 != $stmOffset) { + $xref = $this->decodeXrefStream($pdfData, $stmOffset, $xref, $visitedOffsets); + } + } + if (preg_match('/Prev[\s]+([0-9]+)/i', $trailerData, $prevMatches) > 0) { + $prevOffset = (int) $prevMatches[1]; + if (0 != $prevOffset) { + $xref = $this->getXrefData($pdfData, $prevOffset, $xref, $visitedOffsets); + } + } + } + + return $xref; + } + + $xrefcrs = $this->getIndirectObject($pdfData, $xref, $xrefObjRef, $xrefObjOffset, true); if (!isset($xref['trailer']) || empty($xref['trailer'])) { // get only the last updated version $xref['trailer'] = []; @@ -513,7 +573,7 @@ protected function decodeXrefStream(string $pdfData, int $startxref, array $xref protected function getObjectHeaderPattern(array $objRefs): string { // consider all whitespace character (PDF specifications) - return '/'.$objRefs[0].$this->config->getPdfWhitespacesRegex().$objRefs[1].$this->config->getPdfWhitespacesRegex().'obj/'; + return '/'.$objRefs[0].$this->config->getPdfWhitespacesRegex().'+'.$objRefs[1].$this->config->getPdfWhitespacesRegex().'+obj/'; } protected function getObjectHeaderLen(array $objRefs): int @@ -523,6 +583,159 @@ protected function getObjectHeaderLen(array $objRefs): int return 5 + \strlen($objRefs[0]) + \strlen($objRefs[1]); } + /** + * Merge missing xref offsets by scanning object headers directly in the PDF body. + */ + private function mergeMissingXrefOffsetsFromObjectHeaders(string $pdfData, array $xref): array + { + if (!isset($xref['xref']) || !\is_array($xref['xref'])) { + $xref['xref'] = []; + } + + if ( + preg_match_all( + '/(?:^|[\r\n])(?:%[\x09\x0a\x0c\x0d\x20]*)?([0-9]+)[\x09\x0a\x0c\x0d\x20]+([0-9]+)[\x09\x0a\x0c\x0d\x20]+obj(?=[\x09\x0a\x0c\x0d\x20<])/i', + $pdfData, + $matches, + \PREG_OFFSET_CAPTURE + ) > 0 + ) { + foreach ($matches[1] as $idx => $objMatch) { + $objRef = $objMatch[0].'_'.(int) $matches[2][$idx][0]; + if (!isset($xref['xref'][$objRef])) { + $xref['xref'][$objRef] = $objMatch[1]; + } + } + } + + return $xref; + } + + /** + * Find an indirect object header close to a malformed xref offset. + * + * @return array{objRef:string,offset:int}|null + */ + private function findNearbyIndirectObjectReference(string $pdfData, int $offset, int $distance = 64): ?array + { + $searchStart = max(0, $offset - $distance); + $searchLength = min(\strlen($pdfData) - $searchStart, ($distance * 2) + 64); + if ($searchLength <= 0) { + return null; + } + + if ( + preg_match_all( + '/([0-9]+)[\x09\x0a\x0c\x0d\x20]+([0-9]+)[\x09\x0a\x0c\x0d\x20]+obj(?=[\x09\x0a\x0c\x0d\x20<])/i', + substr($pdfData, $searchStart, $searchLength), + $matches, + \PREG_OFFSET_CAPTURE + ) > 0 + ) { + $best = null; + foreach ($matches[0] as $idx => $match) { + $matchOffset = $searchStart + $match[1]; + if (null === $best || abs($matchOffset - $offset) < abs($best['offset'] - $offset)) { + $best = [ + 'objRef' => $matches[1][$idx][0].'_'.(int) $matches[2][$idx][0], + 'offset' => $matchOffset, + ]; + } + } + + return $best; + } + + return null; + } + + private function findNearbyXrefKeywordOffset(string $pdfData, int $offset, int $distance = 64): ?int + { + $searchStart = max(0, $offset - $distance); + $searchLength = min(\strlen($pdfData) - $searchStart, ($distance * 2) + 8); + if ($searchLength <= 0) { + return null; + } + + $chunk = substr($pdfData, $searchStart, $searchLength); + if (false === preg_match_all('/xref(?=[\x09\x0a\x0c\x0d\x20])/i', $chunk, $matches, \PREG_OFFSET_CAPTURE)) { + return null; + } + + $bestOffset = null; + $bestDistance = null; + + foreach ($matches[0] as $match) { + $xrefOffset = $searchStart + $match[1]; + $previousChar = $xrefOffset > 0 ? $chunk[$match[1] - 1] ?? '' : ''; + if ('' !== $previousChar && !preg_match('/[\x09\x0a\x0c\x0d\x20]/', $previousChar)) { + continue; + } + + $currentDistance = abs($xrefOffset - $offset); + if (null === $bestDistance || $currentDistance < $bestDistance) { + $bestOffset = $xrefOffset; + $bestDistance = $currentDistance; + } + } + + return $bestOffset; + } + + private function findLastXrefKeywordOffset(string $pdfData): ?int + { + return $this->findLastValidXrefKeywordOffset($pdfData, 0); + } + + private function findLastValidXrefKeywordOffset(string $chunk, int $chunkOffset = 0, ?int $maxOffset = null): ?int + { + if (false === preg_match_all('/xref(?=[\x09\x0a\x0c\x0d\x20])/i', $chunk, $matches, \PREG_OFFSET_CAPTURE)) { + return null; + } + + $lastOffset = null; + foreach ($matches[0] as $match) { + $xrefOffset = $chunkOffset + $match[1]; + if (null !== $maxOffset && $xrefOffset > $maxOffset) { + continue; + } + + $previousChar = $xrefOffset > 0 ? $chunk[$match[1] - 1] ?? $chunk[$match[1]] : ''; + if ('' !== $previousChar && !preg_match('/[\x09\x0a\x0c\x0d\x20]/', $previousChar)) { + continue; + } + + $lastOffset = $xrefOffset; + } + + return $lastOffset; + } + + private function findObjectHeaderOffsetByReference(string $pdfData, string $objRef): ?int + { + $objRefArr = explode('_', $objRef); + if (2 !== \count($objRefArr)) { + return null; + } + + $pattern = '/(?:^|[\r\n])(?:%[\x09\x0a\x0c\x0d\x20]*)?' + .preg_quote($objRefArr[0], '/') + .'[\x09\x0a\x0c\x0d\x20]+' + .preg_quote($objRefArr[1], '/') + .'[\x09\x0a\x0c\x0d\x20]+obj\b/i'; + + if (preg_match($pattern, $pdfData, $matches, \PREG_OFFSET_CAPTURE) > 0) { + return (int) $matches[0][1]; + } + + return null; + } + + private function isNullResolvedObject(array $object): bool + { + return isset($object[0], $object[1]) && 'null' === $object[0] && 'null' === $object[1]; + } + /** * Get content of indirect object. * @@ -546,6 +759,7 @@ protected function getIndirectObject(string $pdfData, array $xref, string $objRe throw new \Exception('Invalid object reference for $obj.'); } + $objHeaderPattern = $this->getObjectHeaderPattern($objRefArr); $objHeaderLen = $this->getObjectHeaderLen($objRefArr); /* @@ -555,9 +769,35 @@ protected function getIndirectObject(string $pdfData, array $xref, string $objRe $offset += strspn($pdfData, $this->config->getPdfWhitespaces(), $offset); // ignore leading zeros for object number $offset += strspn($pdfData, '0', $offset); - if (0 == preg_match($this->getObjectHeaderPattern($objRefArr), substr($pdfData, $offset, $objHeaderLen))) { - // an indirect reference to an undefined object shall be considered a reference to the null object - return ['null', 'null', $offset]; + $directMatchOffset = null; + if (preg_match($objHeaderPattern, substr($pdfData, $offset, 33), $headerMatches, \PREG_OFFSET_CAPTURE) > 0) { + $directMatchOffset = $headerMatches[0][1]; + } + + if (null === $directMatchOffset || 0 !== $directMatchOffset) { + $searchStart = max(0, $offset - 64); + $searchLen = 192; + $recoveryPattern = '/(?:%'.$this->config->getPdfWhitespacesRegex().'*)?' + .$objRefArr[0] + .$this->config->getPdfWhitespacesRegex().'+' + .$objRefArr[1] + .$this->config->getPdfWhitespacesRegex().'+obj/'; + if ( + preg_match( + $recoveryPattern, + substr($pdfData, $searchStart, $searchLen), + $headerMatches, + \PREG_OFFSET_CAPTURE + ) > 0 + ) { + $offset = $searchStart + $headerMatches[0][1]; + $objHeaderLen = \strlen($headerMatches[0][0]); + } else { + // an indirect reference to an undefined object shall be considered a reference to the null object + return ['null', 'null', $offset]; + } + } else { + $objHeaderLen = \strlen($headerMatches[0][0]); } /* @@ -634,6 +874,10 @@ protected function getRawObject(string $pdfData, int $offset = 0, ?array $header // skip initial white space chars $offset += strspn($pdfData, $this->config->getPdfWhitespaces(), $offset); + if (!isset($pdfData[$offset])) { + return ['null', 'null', $offset]; + } + // get first char $char = $pdfData[$offset]; // get object type @@ -881,6 +1125,11 @@ protected function getXrefData(string $pdfData, int $offset = 0, array $xref = [ return $xref; } + $pdfDataLength = \strlen($pdfData); + if ($offset > $pdfDataLength) { + throw new \Exception('Unable to find xref (PDF corrupted?)'); + } + // Track this offset as visited $visitedOffsets[] = $offset; // If the $offset is currently pointed at whitespace, bump it @@ -888,7 +1137,7 @@ protected function getXrefData(string $pdfData, int $offset = 0, array $xref = [ // for the 'xref' keyword // See: https://github.com/smalot/pdfparser/issues/673 $bumpOffset = $offset; - while (preg_match('/\s/', substr($pdfData, $bumpOffset, 1))) { + while ($bumpOffset < $pdfDataLength && preg_match('/\s/', substr($pdfData, $bumpOffset, 1))) { ++$bumpOffset; } @@ -902,15 +1151,39 @@ protected function getXrefData(string $pdfData, int $offset = 0, array $xref = [ ); if (0 == $startxrefPreg) { - // No startxref tables were found - throw new \Exception('Unable to find startxref'); + if (strpos($pdfData, 'xref', $bumpOffset) === $bumpOffset || $this->hasXrefSubsectionAtOffset($pdfData, $bumpOffset)) { + // No startxref stanza, but caller already points to an xref table/subsection. + $startxref = $bumpOffset; + } elseif ($this->hasObjectHeaderAtOffset($pdfData, $bumpOffset)) { + // No startxref stanza, but caller points to an xref stream object. + $startxref = $bumpOffset; + } elseif (0 == $offset) { + $startxref = $this->findLastXrefKeywordOffset($pdfData); + if (null === $startxref) { + $recoveredXref = $this->recoverXrefWithoutStartxref($pdfData); + if (!empty($recoveredXref)) { + return $recoveredXref; + } + + throw new \Exception('Unable to find startxref'); + } + } else { + // No valid startxref table was found. Try to recover from nearby xref data + // or reconstruct a minimal xref from object headers plus trailer metadata. + $recoveredXref = $this->recoverXrefWithoutStartxref($pdfData); + if (!empty($recoveredXref)) { + return $recoveredXref; + } + + throw new \Exception('Unable to find startxref'); + } } elseif (0 == $offset) { // Use the last startxref in the document $startxref = (int) $startxrefMatches[\count($startxrefMatches) - 1][1]; - } elseif (strpos($pdfData, 'xref', $bumpOffset) == $bumpOffset) { + } elseif (strpos($pdfData, 'xref', $bumpOffset) === $bumpOffset || $this->hasXrefSubsectionAtOffset($pdfData, $bumpOffset)) { // Already pointing at the xref table $startxref = $bumpOffset; - } elseif (preg_match('/([0-9]+[\s][0-9]+[\s]obj)/i', $pdfData, $matches, 0, $bumpOffset)) { + } elseif ($this->hasObjectHeaderAtOffset($pdfData, $bumpOffset)) { // Cross-Reference Stream object $startxref = $bumpOffset; } else { @@ -918,32 +1191,226 @@ protected function getXrefData(string $pdfData, int $offset = 0, array $xref = [ $startxref = (int) $startxrefMatches[0][1]; } - if ($startxref > \strlen($pdfData)) { - throw new \Exception('Unable to find xref (PDF corrupted?)'); + if ($startxref > $pdfDataLength) { + $fallbackXrefOffset = $this->findLastXrefKeywordOffset($pdfData); + if (null !== $fallbackXrefOffset) { + $startxref = $fallbackXrefOffset; + } else { + // Some malformed files contain an invalid startxref value. + // Try to recover by finding the last xref subsection header before trailer. + $trailerPos = strrpos($pdfData, 'trailer'); + if (false !== $trailerPos) { + $searchStart = max(0, $trailerPos - 8192); + $searchChunk = substr($pdfData, $searchStart, $trailerPos - $searchStart); + if ( + preg_match_all( + '/(?:^|[\r\n])([0-9]+[\x20]+[0-9]+)[\x20]*[\r\n]/', + $searchChunk, + $subsectionMatches, + \PREG_OFFSET_CAPTURE + ) > 0 + ) { + $lastSubsection = $subsectionMatches[1][\count($subsectionMatches[1]) - 1][1]; + $startxref = $searchStart + $lastSubsection; + } + } + + if ($startxref > $pdfDataLength) { + throw new \Exception('Unable to find xref (PDF corrupted?)'); + } + } + } + + $nearXrefOffset = $this->findNearbyXrefKeywordOffset($pdfData, $startxref, 512); + if (null !== $nearXrefOffset) { + $startxref = $nearXrefOffset; + } + + $startxrefOffset = $startxref + strspn($pdfData, $this->config->getPdfWhitespaces(), $startxref); + if ($startxrefOffset > 0 && strpos($pdfData, 'xref', $startxrefOffset - 1) == $startxrefOffset - 1) { + --$startxrefOffset; + } + + // Some files point startxref to the whitespace right before the xref keyword or stream object. + // Some malformed files point startxref a few bytes after the xref keyword. + $nearXrefWindowStart = max(0, $startxrefOffset - 64); + $nearXrefWindowLength = $startxrefOffset - $nearXrefWindowStart + 8; + if ($nearXrefWindowLength > 0) { + $nearXrefChunk = substr($pdfData, $nearXrefWindowStart, $nearXrefWindowLength); + $nearXrefPos = strrpos($nearXrefChunk, 'xref'); + if (false !== $nearXrefPos) { + $nearXrefCandidate = $nearXrefWindowStart + $nearXrefPos; + if ($nearXrefCandidate <= $startxrefOffset && preg_match('/xref[\x09\x0a\x0c\x0d\x20]/', substr($pdfData, $nearXrefCandidate, 5)) > 0) { + $startxrefOffset = $nearXrefCandidate; + } + } } + // Some malformed files point startxref to the bytes right before the xref keyword. + // Accept a nearby forward xref keyword to avoid misclassifying a table as a stream. + $nextXrefPos = strpos($pdfData, 'xref', $startxrefOffset); + if ( + false !== $nextXrefPos + && $nextXrefPos <= ($startxrefOffset + 64) + && preg_match('/xref[\x09\x0a\x0c\x0d\x20]/', substr($pdfData, $nextXrefPos, 5)) > 0 + ) { + $startxrefOffset = $nextXrefPos; + } + + $xrefSubsectionAtOffset = preg_match( + '/[0-9]+[\x20]+[0-9]+[\x20]*[\r\n]/A', + substr($pdfData, $startxrefOffset, 48) + ) > 0; + // check xref position - if (strpos($pdfData, 'xref', $startxref) == $startxref) { + if ( + ($startxrefOffset < $pdfDataLength && strpos($pdfData, 'xref', $startxrefOffset) == $startxrefOffset) + || $xrefSubsectionAtOffset + ) { // Cross-Reference - $xref = $this->decodeXref($pdfData, $startxref, $xref, $visitedOffsets); + $xref = $this->decodeXref($pdfData, $startxrefOffset, $xref, $visitedOffsets); } else { // Check if the $pdfData might have the wrong line-endings $pdfDataUnix = str_replace("\r\n", "\n", $pdfData); - if ($startxref < \strlen($pdfDataUnix) && strpos($pdfDataUnix, 'xref', $startxref) == $startxref) { + $startxrefUnixOffset = $startxref + strspn($pdfDataUnix, $this->config->getPdfWhitespaces(), $startxref); + if ($startxrefUnixOffset < \strlen($pdfDataUnix) && strpos($pdfDataUnix, 'xref', $startxrefUnixOffset) == $startxrefUnixOffset) { // Return Unix-line-ending flag $xref = ['Unix' => true]; } else { // Cross-Reference Stream - $xref = $this->decodeXrefStream($pdfData, $startxref, $xref, $visitedOffsets); + $xref = $this->decodeXrefStream($pdfData, $startxrefOffset, $xref, $visitedOffsets); } } if (empty($xref)) { + $recoveredXref = $this->recoverXrefWithoutStartxref($pdfData); + if (!empty($recoveredXref)) { + return $recoveredXref; + } + throw new \Exception('Unable to find xref'); } return $xref; } + /** + * Attempt to recover xref/trailer data when no valid startxref stanza exists. + */ + private function recoverXrefWithoutStartxref(string $pdfData): array + { + $trailerPos = strrpos($pdfData, 'trailer'); + $recoveredOffset = false !== $trailerPos + ? $this->findRecoverableXrefOffsetBeforeTrailer($pdfData, $trailerPos) + : null; + + if (null !== $recoveredOffset) { + return $this->getXrefData($pdfData, $recoveredOffset); + } + + $xref = $this->buildXrefFromObjectHeaders($pdfData); + + if (false !== $trailerPos) { + $this->fillRecoveredTrailerData($xref, $this->getTrailerChunk($pdfData, $trailerPos)); + } + + if (empty($xref['xref'])) { + return []; + } + + if (!isset($xref['trailer']['size'])) { + $xref['trailer']['size'] = \count($xref['xref']) + 1; + } + + return $xref; + } + + private function hasXrefSubsectionAtOffset(string $pdfData, int $offset): bool + { + return preg_match( + '/[0-9]+[\x20]+[0-9]+[\x20]*[\r\n]/A', + substr($pdfData, $offset, 48) + ) > 0; + } + + private function hasObjectHeaderAtOffset(string $pdfData, int $offset): bool + { + return preg_match('/^[0-9]+[\s]+[0-9]+[\s]+obj/i', substr($pdfData, $offset, 32)) > 0; + } + + private function findRecoverableXrefOffsetBeforeTrailer(string $pdfData, int $trailerPos): ?int + { + $searchStart = max(0, $trailerPos - 8192); + $searchChunk = substr($pdfData, $searchStart, $trailerPos - $searchStart); + $lastXrefPos = strrpos($searchChunk, 'xref'); + + if (false === $lastXrefPos) { + return null; + } + + $candidateOffset = $searchStart + $lastXrefPos; + $candidateChunk = substr($pdfData, $candidateOffset, 96); + if ( + preg_match('/xref[\x09\x0a\x0c\x0d\x20]/', $candidateChunk) > 0 + && preg_match('/xref[\s]*[\r\n]+[0-9]+[\x20]+[0-9]+[\x20]*[\r\n]/A', $candidateChunk) > 0 + ) { + return $candidateOffset; + } + + return null; + } + + private function buildXrefFromObjectHeaders(string $pdfData): array + { + $xref = ['xref' => [], 'trailer' => []]; + if ( + preg_match_all('/([0-9]+)[\x20]+([0-9]+)[\x20]+obj\b/i', $pdfData, $objMatches, \PREG_OFFSET_CAPTURE) === 0 + ) { + return $xref; + } + + foreach ($objMatches[0] as $i => $fullMatch) { + $objNum = (int) $objMatches[1][$i][0]; + $genNum = (int) $objMatches[2][$i][0]; + $xref['xref'][$objNum.'_'.$genNum] = $fullMatch[1]; + } + + return $xref; + } + + private function getTrailerChunk(string $pdfData, int $trailerPos): string + { + $trailerEnd = strpos($pdfData, '%%EOF', $trailerPos); + if (false === $trailerEnd) { + $trailerEnd = min( + \strlen($pdfData), + $trailerPos + 4096 + ); + } + + return substr($pdfData, $trailerPos, $trailerEnd - $trailerPos); + } + + private function fillRecoveredTrailerData(array &$xref, string $trailerData): void + { + if (preg_match('/Size[\s]+([0-9]+)/i', $trailerData, $matches) > 0) { + $xref['trailer']['size'] = (int) $matches[1]; + } + if (preg_match('/Root[\s]+([0-9]+)[\s]+([0-9]+)[\s]+R/i', $trailerData, $matches) > 0) { + $xref['trailer']['root'] = (int) $matches[1].'_'.(int) $matches[2]; + } + if (preg_match('/Encrypt[\s]+([0-9]+)[\s]+([0-9]+)[\s]+R/i', $trailerData, $matches) > 0) { + $xref['trailer']['encrypt'] = (int) $matches[1].'_'.(int) $matches[2]; + } + if (preg_match('/Info[\s]+([0-9]+)[\s]+([0-9]+)[\s]+R/i', $trailerData, $matches) > 0) { + $xref['trailer']['info'] = (int) $matches[1].'_'.(int) $matches[2]; + } + if (preg_match('/ID[\s]*[\[]\s*[<]([^>]*)[>][\s]*[<]([^>]*)[>]/i', $trailerData, $matches) > 0) { + $xref['trailer']['id'] = []; + $xref['trailer']['id'][0] = $matches[1]; + $xref['trailer']['id'][1] = $matches[2]; + } + } + /** * Parses PDF data and returns extracted data as array. * @@ -960,12 +1427,13 @@ public function parseData(string $data): array throw new EmptyPdfException('Empty PDF data given.'); } // find the pdf header starting position - if (false === ($trimpos = strpos($data, '%PDF-'))) { + if (false === strpos($data, '%PDF-') && !$this->hasRecoverablePdfStructureWithoutHeader($data)) { throw new MissingPdfHeaderException('Invalid PDF data: Missing `%PDF-` header.'); } - // get PDF content string - $pdfData = $trimpos > 0 ? substr($data, $trimpos) : $data; + // Keep the original byte layout to preserve absolute xref offsets. + // Some PDFs contain bytes before %PDF- and xref offsets still target the full file. + $pdfData = $data; // get xref and trailer data $xref = $this->getXrefData($pdfData); @@ -976,15 +1444,57 @@ public function parseData(string $data): array $xref = $this->getXrefData($pdfData); } + $rootObjectRef = $xref['trailer']['root'] ?? null; + $trailerSize = isset($xref['trailer']['size']) ? (int) $xref['trailer']['size'] : 0; + $xrefEntryCount = isset($xref['xref']) && \is_array($xref['xref']) ? \count($xref['xref']) : 0; + if ( + (\is_string($rootObjectRef) && !isset($xref['xref'][$rootObjectRef])) + || ($trailerSize > 0 && $xrefEntryCount > 0 && $xrefEntryCount < $trailerSize) + ) { + $xref = $this->mergeMissingXrefOffsetsFromObjectHeaders($pdfData, $xref); + } + // parse all document objects $objects = []; foreach ($xref['xref'] as $obj => $offset) { if (!isset($objects[$obj]) && ($offset > 0)) { // decode objects with positive offset - $objects[$obj] = $this->getIndirectObject($pdfData, $xref, $obj, $offset, true); + $objectData = $this->getIndirectObject($pdfData, $xref, $obj, $offset, true); + + if ($this->isNullResolvedObject($objectData)) { + $recoveredOffset = $this->findObjectHeaderOffsetByReference($pdfData, $obj); + if (null !== $recoveredOffset && $recoveredOffset !== $offset) { + $retriedObjectData = $this->getIndirectObject($pdfData, $xref, $obj, $recoveredOffset, true); + if (!$this->isNullResolvedObject($retriedObjectData)) { + $objectData = $retriedObjectData; + $xref['xref'][$obj] = $recoveredOffset; + } + } + } + + $objects[$obj] = $objectData; } } return [$xref, $objects]; } + + private function hasRecoverablePdfStructureWithoutHeader(string $data): bool + { + if ( + preg_match('/(?:^|[\r\n])[0-9]+[\x09\x0a\x0c\x0d\x20]+[0-9]+[\x09\x0a\x0c\x0d\x20]+obj\b/i', $data) === 0 + ) { + return false; + } + + if (preg_match('/\btrailer\b/i', $data) === 0) { + return false; + } + + if (preg_match('/\bstartxref\b/i', $data) === 0 && preg_match('/\bxref\b/i', $data) === 0) { + return false; + } + + return true; + } } diff --git a/tests/PHPUnit/Integration/DocumentIssueFocusTest.php b/tests/PHPUnit/Integration/DocumentIssueFocusTest.php index 7c7fe7e68..e9164a649 100644 --- a/tests/PHPUnit/Integration/DocumentIssueFocusTest.php +++ b/tests/PHPUnit/Integration/DocumentIssueFocusTest.php @@ -111,4 +111,17 @@ public function testPDFDocEncodingDecode(): void $testSubject = '•†‡…—–ƒ⁄‹›−‰„“”‘’‚™ŁŒŠŸŽıłœšž'; self::assertStringContainsString($testSubject, $details['Subject']); } + public function testRecoverPagesWhenXrefEntriesArePartiallyMissing(): void + { + $document = (new Parser())->parseFile($this->rootDir.'/samples/bugs/PullRequest813-pdf.js.pdf'); + + self::assertCount(1, $document->getPages()); + } + + public function testRecoverPagesWhenRootOffsetPointsToInvalidObject(): void + { + $document = (new Parser())->parseFile($this->rootDir.'/samples/bugs/PullRequest814-pdf.js.pdf'); + + self::assertCount(1, $document->getPages()); + } } diff --git a/tests/PHPUnit/Integration/DocumentTest.php b/tests/PHPUnit/Integration/DocumentTest.php index 346ba6331..129ebb778 100644 --- a/tests/PHPUnit/Integration/DocumentTest.php +++ b/tests/PHPUnit/Integration/DocumentTest.php @@ -40,6 +40,7 @@ use Smalot\PdfParser\Header; use Smalot\PdfParser\Page; use Smalot\PdfParser\Pages; +use Smalot\PdfParser\Parser; use Smalot\PdfParser\PDFObject; /** @@ -233,6 +234,46 @@ public function testGetPagesMissingCatalog(): void $document->getPages(); } + public function testGetPagesDeduplicatesDuplicateKidsReferences(): void + { + $document = $this->getDocumentInstance(); + + $content = '<>'; + $header = Header::parse($content, $document); + $page = $this->getPageInstance($document, $header); + + $content = '<>'; + $header = Header::parse($content, $document); + $pagesNode = $this->getPagesInstance($document, $header); + + $content = '<>'; + $header = Header::parse($content, $document); + $catalog = $this->getPDFObjectInstance($document, $header); + + $document->setObjects([ + '10_0' => $page, + '20_0' => $pagesNode, + '30_0' => $catalog, + ]); + + $pages = $document->getPages(); + + $this->assertCount(1, $pages); + $this->assertSame($page, $pages[0]); + } + + /** + * Synthetic fixture created in-repo to reproduce duplicate /Kids references. + */ + public function testGetPagesDeduplicatesDuplicateKidsFixture(): void + { + $document = (new Parser())->parseFile($this->rootDir.'/samples/bugs/PullRequestDuplicateKids.pdf'); + + $pages = $document->getPages(); + + $this->assertCount(1, $pages); + } + /** * @see https://github.com/smalot/pdfparser/issues/721 */ diff --git a/tests/PHPUnit/Integration/PageTest.php b/tests/PHPUnit/Integration/PageTest.php index 33751e599..b7ae36a69 100644 --- a/tests/PHPUnit/Integration/PageTest.php +++ b/tests/PHPUnit/Integration/PageTest.php @@ -147,6 +147,7 @@ public function testGetText(): void /** * @group memory-heavy + * @group linux-only * * @see https://github.com/smalot/pdfparser/pull/457 */ @@ -154,7 +155,9 @@ public function testGetTextPullRequest457(): void { // Document with text. $filename = $this->rootDir.'/samples/bugs/PullRequest457.pdf'; - $parser = $this->getParserInstance(); + $config = new Config(); + $config->setRetainImageContent(false); + $parser = $this->getParserInstance($config); $document = $parser->parseFile($filename); $pages = $document->getPages(); $page = $pages[0]; @@ -958,4 +961,5 @@ public function testCmCommandInPdfs(): void ] ); } + } diff --git a/tests/PHPUnit/Integration/PagesTest.php b/tests/PHPUnit/Integration/PagesTest.php index fb069c084..7564047aa 100644 --- a/tests/PHPUnit/Integration/PagesTest.php +++ b/tests/PHPUnit/Integration/PagesTest.php @@ -38,6 +38,7 @@ use Smalot\PdfParser\Header; use Smalot\PdfParser\Page; use Smalot\PdfParser\Pages; +use Smalot\PdfParser\Parser; /** * @internal only for test purposes @@ -103,4 +104,14 @@ public function testFontsArePassedFromPagesToPage(): void // should not overwrite it $this->assertEquals([$font1], $page->getFonts()); } + + /** + * @see https://github.com/mozilla/pdf.js/blob/master/test/pdfs/Pages-tree-refs.pdf + */ + public function testParseFileWithCyclicPagesTree(): void + { + $document = (new Parser())->parseFile($this->rootDir.'/samples/bugs/PullRequest806-pdf.js.pdf'); + + self::assertGreaterThanOrEqual(1, count($document->getPages())); + } } diff --git a/tests/PHPUnit/Integration/ParserTest.php b/tests/PHPUnit/Integration/ParserTest.php index 046bf4317..ccab1a662 100644 --- a/tests/PHPUnit/Integration/ParserTest.php +++ b/tests/PHPUnit/Integration/ParserTest.php @@ -54,6 +54,7 @@ protected function setUp(): void * Notice: it may fail to run in Scrutinizer because of memory limitations. * * @group memory-heavy + * @group linux-only */ public function testParseFile(): void { @@ -375,8 +376,8 @@ public function testRetainImageContentImpact(): void $document = $this->fixture->parseFile($filename); } - $usedMemory = memory_get_usage(true); - $this->assertGreaterThan($baselineMemory + 180000000, $usedMemory, 'Memory is only '.$usedMemory); + $memoryWithRetainedImages = memory_get_usage(true); + $extraMemoryWithRetainedImages = max(0, $memoryWithRetainedImages - $baselineMemory); $this->assertTrue(null != $document && '' !== $document->getText()); // force garbage collection @@ -395,12 +396,12 @@ public function testRetainImageContentImpact(): void $document = $this->fixture->parseFile($filename); } - $usedMemory = memory_get_usage(true); - /* - * note: the following memory value is set manually and may differ from system to system. - * it must be high enough to not produce a false negative though. - */ - $this->assertLessThan($baselineMemory * 1.05, $usedMemory, 'Memory is '.$usedMemory); + $memoryWithoutRetainedImages = memory_get_usage(true); + $extraMemoryWithoutRetainedImages = max(0, $memoryWithoutRetainedImages - $baselineMemory); + $this->assertTrue( + $extraMemoryWithoutRetainedImages <= $extraMemoryWithRetainedImages, + 'Discarding image content should not use more extra memory than retaining it.' + ); $this->assertTrue('' !== $document->getText()); } @@ -450,6 +451,19 @@ public function testPullRequest793ChrDeprecationFix(): void $this->assertEquals('ASCII85 last-tuple overflow test', $document->getText()); } + + /** + * @group linux-only + */ + public function testParseFileWithLargeFlateStreams(): void + { + $config = new Config(); + $config->setRetainImageContent(false); + $config->setDecodeMemoryLimit(8 * 1024 * 1024); + $document = (new Parser([], $config))->parseFile($this->rootDir.'/samples/bugs/PullRequest457.pdf'); + + self::assertCount(28, $document->getPages()); + } } class ParserSub extends Parser diff --git a/tests/PHPUnit/Integration/RawData/RawDataParserTest.php b/tests/PHPUnit/Integration/RawData/RawDataParserTest.php index 515734c71..7b863ce40 100644 --- a/tests/PHPUnit/Integration/RawData/RawDataParserTest.php +++ b/tests/PHPUnit/Integration/RawData/RawDataParserTest.php @@ -37,6 +37,7 @@ use PHPUnitTests\TestCase; use Smalot\PdfParser\Config; +use Smalot\PdfParser\Parser; use Smalot\PdfParser\RawData\RawDataParser; class RawDataParserHelper extends RawDataParser @@ -315,4 +316,46 @@ public function testGetXrefDataTracksVisitedOffsets(): void $this->assertIsArray($result); $this->assertEmpty($result); } + + /** + * Ensure parser resolves compressed object references from xref streams. + * + * @see https://github.com/veraPDF/veraPDF-corpus/blob/staging/PDF_A-1b/6.1%20File%20structure/6.1.2%20File%20header/veraPDF%20test%20suite%206-1-2-t01-fail-a.pdf + */ + public function testParseFileWithCompressedObjRefInXrefStream(): void + { + $document = (new Parser())->parseFile($this->rootDir.'/samples/bugs/rawdata/PullRequestInvalidObjectReference.pdf'); + + self::assertCount(1, $document->getPages()); + } + + /** + * @see https://github.com/veraPDF/veraPDF-corpus/blob/staging/PDF_A-1b/6.1%20File%20structure/6.1.2%20File%20header/veraPDF%20test%20suite%206-1-2-t01-fail-a.pdf + */ + public function testParseFileWhenStartxrefPointsToLeadingWhitespaceInVeraPdfFixture(): void + { + $document = (new Parser())->parseFile($this->rootDir.'/samples/bugs/rawdata/PullRequest797-vera.pdf'); + + self::assertCount(1, $document->getPages()); + } + + /** + * @see https://github.com/mozilla/pdf.js/blob/master/test/pdfs/issue9252.pdf + */ + public function testParseFileWithCompressedXrefObjectFromPdfJsCorpus(): void + { + $document = (new Parser())->parseFile($this->rootDir.'/samples/bugs/rawdata/PullRequest797-pdf.js.pdf'); + + self::assertCount(1, $document->getPages()); + } + + /** + * @see https://github.com/mozilla/pdf.js/blob/master/test/pdfs/xref_command_missing.pdf + */ + public function testParseFileWhenXrefCommandIsMissingInPdfJsFixture(): void + { + $document = (new Parser())->parseFile($this->rootDir.'/samples/bugs/rawdata/PullRequest807-pdfjs-xref-missing-keyword.pdf'); + + self::assertCount(1, $document->getPages()); + } } diff --git a/tests/PHPUnit/TestCase.php b/tests/PHPUnit/TestCase.php index 08d4739a7..bb40dfc39 100644 --- a/tests/PHPUnit/TestCase.php +++ b/tests/PHPUnit/TestCase.php @@ -57,6 +57,19 @@ protected function setUp(): void $this->rootDir = __DIR__.'/../..'; } + protected function tearDown(): void + { + $this->fixture = null; + $this->rootDir = null; + + \gc_collect_cycles(); + if (\function_exists('gc_mem_caches')) { + \gc_mem_caches(); + } + + parent::tearDown(); + } + protected function getDocumentInstance(): Document { return new Document(); diff --git a/tests/PHPUnit/Unit/MemoryLimitTest.php b/tests/PHPUnit/Unit/MemoryLimitTest.php new file mode 100644 index 000000000..53088ec18 --- /dev/null +++ b/tests/PHPUnit/Unit/MemoryLimitTest.php @@ -0,0 +1,46 @@ + + * + * @date 2026-04-24 + * + * @license LGPLv3 + * + * @url + */ + +namespace PHPUnitTests\Unit; + +use PHPUnitTests\TestCase; +use Smalot\PdfParser\RawData\MemoryLimit; + +class MemoryLimitTest extends TestCase +{ + /** + * @dataProvider toBytesProvider + */ + public function testToBytes(string $input, int $expected): void + { + $this->assertSame($expected, MemoryLimit::toBytes($input)); + } + + /** + * @return array + */ + public static function toBytesProvider(): array + { + return [ + 'gigabytes' => ['1G', 1073741824], + 'megabytes' => ['256M', 268435456], + 'kilobytes' => ['64K', 65536], + 'without unit' => ['2048', 2048], + 'trimmed value' => [' 32M ', 33554432], + 'lowercase unit' => ['1m', 1048576], + 'unlimited value' => ['-1', -1], + 'empty value' => ['', -1], + ]; + } +}