Use document size instead of file size while parsing.

We should use document size instead of File size,
because all offsets and sizes was read from document should
take into account of header offset.

Added some tests of parsing of documents with header offset.
Also drop friendship of CPDF_SyntaxParser with CPDF_Parser.

Change-Id: Iebec75ab2ee07fb644a6c653b4ef5c2e09af09fe
Reviewed-on: https://pdfium-review.googlesource.com/35830
Commit-Queue: Art Snake <art-snake@yandex-team.ru>
Reviewed-by: Lei Zhang <thestig@chromium.org>

1 files changed, 8 insertions, 9 deletions

diff --git a/core/fpdfapi/parser/cpdf_linearized_header.cpp b/core/fpdfapi/parser/cpdf_linearized_header.cpp
index 5032bc3807..8286e0fbe3 100644
--- a/core/fpdfapi/parser/cpdf_linearized_header.cpp
+++ b/core/fpdfapi/parser/cpdf_linearized_header.cpp
@@ -38,17 +38,17 @@ bool IsValidNumericDictionaryValue(const CPDF_Dictionary* pDict,
 }
 
 bool IsLinearizedHeaderValid(const CPDF_LinearizedHeader* header,
-                             FX_FILESIZE file_size) {
+                             FX_FILESIZE document_size) {
   ASSERT(header);
-  return header->GetFileSize() == file_size &&
+  return header->GetFileSize() == document_size &&
          static_cast<int>(header->GetFirstPageNo()) >= 0 &&
          header->GetFirstPageNo() < kMaxInt &&
          header->GetFirstPageNo() < header->GetPageCount() &&
-         header->GetMainXRefTableFirstEntryOffset() < file_size &&
+         header->GetMainXRefTableFirstEntryOffset() < document_size &&
          header->GetPageCount() > 0 &&
-         header->GetFirstPageEndOffset() < file_size &&
-         header->GetLastXRefOffset() < file_size &&
-         header->GetHintStart() < file_size;
+         header->GetFirstPageEndOffset() < document_size &&
+         header->GetLastXRefOffset() < document_size &&
+         header->GetHintStart() < document_size;
 }
 
 }  // namespace
@@ -78,10 +78,9 @@ std::unique_ptr<CPDF_LinearizedHeader> CPDF_LinearizedHeader::Parse(
   auto result = pdfium::WrapUnique(
       new CPDF_LinearizedHeader(pDict.get(), parser->GetPos()));
 
-  if (!IsLinearizedHeaderValid(result.get(),
-                               parser->GetFileAccess()->GetSize())) {
+  if (!IsLinearizedHeaderValid(result.get(), parser->GetDocumentSize()))
     return nullptr;
-  }
+
   return result;
 }