Flip document and parser ownership

This Cl switches the ownership between the parser and the document. Previously
the parser owned the document and we'd jump through hoops during cleanup to
delete the right object. This Cl flips the ownership so the document owns
the parser and simplifies the cleanup logic where needed.

BUG=pdfium:565

Review-Url: https://codereview.chromium.org/2275773003

4 files changed, 21 insertions, 27 deletions

diff --git a/core/fpdfapi/fpdf_parser/cpdf_document.cpp b/core/fpdfapi/fpdf_parser/cpdf_document.cpp
index b11d0c1b79..89b41d5820 100644
--- a/core/fpdfapi/fpdf_parser/cpdf_document.cpp
+++ b/core/fpdfapi/fpdf_parser/cpdf_document.cpp
@@ -483,9 +483,9 @@ int CountPages(CPDF_Dictionary* pPages,
 
 }  // namespace
 
-CPDF_Document::CPDF_Document(CPDF_Parser* pParser)
+CPDF_Document::CPDF_Document(std::unique_ptr<CPDF_Parser> pParser)
     : CPDF_IndirectObjectHolder(),
-      m_pParser(pParser),
+      m_pParser(std::move(pParser)),
       m_pRootDict(nullptr),
       m_pInfoDict(nullptr),
       m_bLinearized(false),
diff --git a/core/fpdfapi/fpdf_parser/cpdf_parser.cpp b/core/fpdfapi/fpdf_parser/cpdf_parser.cpp
index ffd3f79a62..e2bab450be 100644
--- a/core/fpdfapi/fpdf_parser/cpdf_parser.cpp
+++ b/core/fpdfapi/fpdf_parser/cpdf_parser.cpp
@@ -126,7 +126,7 @@ void CPDF_Parser::ShrinkObjectMap(uint32_t objnum) {
 
 void CPDF_Parser::CloseParser() {
   m_bVersionUpdated = false;
-  m_pDocument.reset();
+  m_pDocument = nullptr;
 
   if (m_pTrailer) {
     m_pTrailer->Release();
@@ -158,9 +158,8 @@ void CPDF_Parser::CloseParser() {
   }
 }
 
-CPDF_Parser::Error CPDF_Parser::StartParse(
-    IFX_FileRead* pFileAccess,
-    std::unique_ptr<CPDF_Document> pDocument) {
+CPDF_Parser::Error CPDF_Parser::StartParse(IFX_FileRead* pFileAccess,
+                                           CPDF_Document* pDocument) {
   CloseParser();
 
   m_bXRefStream = FALSE;
@@ -190,7 +189,7 @@ CPDF_Parser::Error CPDF_Parser::StartParse(
     return FORMAT_ERROR;
 
   m_pSyntax->RestorePos(m_pSyntax->m_FileLen - m_pSyntax->m_HeaderOffset - 9);
-  m_pDocument = std::move(pDocument);
+  m_pDocument = pDocument;
 
   FX_BOOL bXRefRebuilt = FALSE;
   if (m_pSyntax->SearchWord("startxref", TRUE, FALSE, 4096)) {
@@ -765,7 +764,7 @@ FX_BOOL CPDF_Parser::RebuildCrossRef() {
                 last_obj = start_pos;
                 FX_FILESIZE obj_end = 0;
                 CPDF_Object* pObject = ParseIndirectObjectAtByStrict(
-                    m_pDocument.get(), obj_pos, objnum, &obj_end);
+                    m_pDocument, obj_pos, objnum, &obj_end);
                 if (CPDF_Stream* pStream = ToStream(pObject)) {
                   if (CPDF_Dictionary* pDict = pStream->GetDict()) {
                     if ((pDict->KeyExist("Type")) &&
@@ -828,8 +827,7 @@ FX_BOOL CPDF_Parser::RebuildCrossRef() {
               last_trailer = pos + i - 7;
               m_pSyntax->RestorePos(pos + i - m_pSyntax->m_HeaderOffset);
 
-              CPDF_Object* pObj =
-                  m_pSyntax->GetObject(m_pDocument.get(), 0, 0, true);
+              CPDF_Object* pObj = m_pSyntax->GetObject(m_pDocument, 0, 0, true);
               if (pObj) {
                 if (!pObj->IsDictionary() && !pObj->AsStream()) {
                   pObj->Release();
@@ -851,7 +849,7 @@ FX_BOOL CPDF_Parser::RebuildCrossRef() {
                           uint32_t dwObjNum =
                               pElement ? pElement->GetObjNum() : 0;
                           if (dwObjNum) {
-                            m_pTrailer->SetAtReference(key, m_pDocument.get(),
+                            m_pTrailer->SetAtReference(key, m_pDocument,
                                                        dwObjNum);
                           } else {
                             m_pTrailer->SetAt(key, pElement->Clone());
@@ -975,7 +973,7 @@ FX_BOOL CPDF_Parser::RebuildCrossRef() {
 }
 
 FX_BOOL CPDF_Parser::LoadCrossRefV5(FX_FILESIZE* pos, FX_BOOL bMainXRef) {
-  CPDF_Object* pObject = ParseIndirectObjectAt(m_pDocument.get(), *pos, 0);
+  CPDF_Object* pObject = ParseIndirectObjectAt(m_pDocument, *pos, 0);
   if (!pObject)
     return FALSE;
 
@@ -1478,7 +1476,7 @@ CPDF_Dictionary* CPDF_Parser::LoadTrailerV4() {
     return nullptr;
 
   std::unique_ptr<CPDF_Object, ReleaseDeleter<CPDF_Object>> pObj(
-      m_pSyntax->GetObject(m_pDocument.get(), 0, 0, true));
+      m_pSyntax->GetObject(m_pDocument, 0, 0, true));
   if (!ToDictionary(pObj.get()))
     return nullptr;
   return pObj.release()->AsDictionary();
@@ -1550,9 +1548,8 @@ FX_BOOL CPDF_Parser::IsLinearizedFile(IFX_FileRead* pFileAccess,
   return FALSE;
 }
 
-CPDF_Parser::Error CPDF_Parser::StartLinearizedParse(
-    IFX_FileRead* pFileAccess,
-    std::unique_ptr<CPDF_Document> pDocument) {
+CPDF_Parser::Error CPDF_Parser::StartLinearizedParse(IFX_FileRead* pFileAccess,
+                                                     CPDF_Document* pDocument) {
   CloseParser();
   m_bXRefStream = FALSE;
   m_LastXRefOffset = 0;
@@ -1567,7 +1564,7 @@ CPDF_Parser::Error CPDF_Parser::StartLinearizedParse(
     return StartParse(pFileAccess, std::move(pDocument));
   }
 
-  m_pDocument = std::move(pDocument);
+  m_pDocument = pDocument;
   FX_FILESIZE dwFirstXRefOffset = m_pSyntax->SavePos();
 
   FX_BOOL bXRefRebuilt = FALSE;
diff --git a/core/fpdfapi/fpdf_parser/include/cpdf_document.h b/core/fpdfapi/fpdf_parser/include/cpdf_document.h
index 31988d8c9d..f3322425ed 100644
--- a/core/fpdfapi/fpdf_parser/include/cpdf_document.h
+++ b/core/fpdfapi/fpdf_parser/include/cpdf_document.h
@@ -40,10 +40,10 @@ class JBig2_DocumentContext;
 
 class CPDF_Document : public CPDF_IndirectObjectHolder {
  public:
-  explicit CPDF_Document(CPDF_Parser* pParser);
+  explicit CPDF_Document(std::unique_ptr<CPDF_Parser> pParser);
   ~CPDF_Document() override;
 
-  CPDF_Parser* GetParser() const { return m_pParser; }
+  CPDF_Parser* GetParser() const { return m_pParser.get(); }
   CPDF_Dictionary* GetRoot() const { return m_pRootDict; }
   CPDF_Dictionary* GetInfo() const { return m_pInfoDict; }
 
@@ -128,7 +128,7 @@ class CPDF_Document : public CPDF_IndirectObjectHolder {
   FX_BOOL CheckOCGVisible(CPDF_Dictionary* pOCG, FX_BOOL bPrinting);
   CPDF_Object* ParseIndirectObject(uint32_t objnum) override;
 
-  CPDF_Parser* m_pParser;
+  std::unique_ptr<CPDF_Parser> m_pParser;
   CPDF_Dictionary* m_pRootDict;
   CPDF_Dictionary* m_pInfoDict;
   CFX_ByteString m_ID1;
diff --git a/core/fpdfapi/fpdf_parser/include/cpdf_parser.h b/core/fpdfapi/fpdf_parser/include/cpdf_parser.h
index a69f0fe38e..d6a5d5703b 100644
--- a/core/fpdfapi/fpdf_parser/include/cpdf_parser.h
+++ b/core/fpdfapi/fpdf_parser/include/cpdf_parser.h
@@ -37,17 +37,14 @@ class CPDF_Parser {
   CPDF_Parser();
   ~CPDF_Parser();
 
-  Error StartParse(IFX_FileRead* pFile,
-                   std::unique_ptr<CPDF_Document> pDocument);
-
-  Error StartLinearizedParse(IFX_FileRead* pFile,
-                             std::unique_ptr<CPDF_Document> pDocument);
+  Error StartParse(IFX_FileRead* pFile, CPDF_Document* pDocument);
+  Error StartLinearizedParse(IFX_FileRead* pFile, CPDF_Document* pDocument);
 
   void SetPassword(const FX_CHAR* password) { m_Password = password; }
   CFX_ByteString GetPassword() { return m_Password; }
   CPDF_Dictionary* GetTrailer() const { return m_pTrailer; }
   FX_FILESIZE GetLastXRefOffset() const { return m_LastXRefOffset; }
-  CPDF_Document* GetDocument() const { return m_pDocument.get(); }
+  CPDF_Document* GetDocument() const { return m_pDocument; }
 
   uint32_t GetPermissions() const;
   uint32_t GetRootObjNum();
@@ -120,7 +117,7 @@ class CPDF_Parser {
   // the objects.
   bool VerifyCrossRefV4();
 
-  std::unique_ptr<CPDF_Document> m_pDocument;
+  CPDF_Document* m_pDocument;  // not owned
   std::unique_ptr<CPDF_SyntaxParser> m_pSyntax;
   bool m_bOwnFileRead;
   int m_FileVersion;