IndirectObjectHolder API updates

This Cl updates the names of the methods in the indirect object holder to better
reflect their usage. The m_LastObjNum is made private and a setter added.

Review-Url: https://codereview.chromium.org/2275593002

10 files changed, 49 insertions, 35 deletions

diff --git a/core/fpdfapi/fpdf_edit/fpdf_edit_create.cpp b/core/fpdfapi/fpdf_edit/fpdf_edit_create.cpp
index c20a483764..9ad1d060cc 100644
--- a/core/fpdfapi/fpdf_edit/fpdf_edit_create.cpp
+++ b/core/fpdfapi/fpdf_edit/fpdf_edit_create.cpp
@@ -1239,7 +1239,7 @@ int32_t CPDF_Creator::WriteOldIndirectObject(uint32_t objnum) {
   bool bObjStm = (object_type == 2) && m_pEncryptDict && !m_pXRefStream;
   if (m_pParser->IsVersionUpdated() || m_bSecurityChanged || bExistInMap ||
       bObjStm) {
-    CPDF_Object* pObj = m_pDocument->GetIndirectObject(objnum);
+    CPDF_Object* pObj = m_pDocument->GetOrParseIndirectObject(objnum);
     if (!pObj) {
       m_ObjectOffset[objnum] = 0;
       return 0;
@@ -1703,7 +1703,7 @@ int32_t CPDF_Creator::WriteDoc_Stage4(IFX_Pause* pPause) {
         return -1;
       }
     } else {
-      if (m_File.AppendDWord(m_pDocument->m_LastObjNum + 1) < 0) {
+      if (m_File.AppendDWord(m_pDocument->GetLastObjNum() + 1) < 0) {
         return -1;
       }
       if (m_File.AppendString(" 0 obj <<") < 0) {
diff --git a/core/fpdfapi/fpdf_parser/cfdf_document.cpp b/core/fpdfapi/fpdf_parser/cfdf_document.cpp
index c039871401..c268503715 100644
--- a/core/fpdfapi/fpdf_parser/cfdf_document.cpp
+++ b/core/fpdfapi/fpdf_parser/cfdf_document.cpp
@@ -65,7 +65,7 @@ void CFDF_Document::ParseStream(IFX_FileRead* pFile, FX_BOOL bOwnFile) {
       if (!pObj)
         break;
 
-      InsertIndirectObject(objnum, pObj);
+      ReplaceIndirectObjectIfHigherGeneration(objnum, pObj);
       word = parser.GetNextWord(nullptr);
       if (word != "endobj")
         break;
diff --git a/core/fpdfapi/fpdf_parser/cpdf_array_unittest.cpp b/core/fpdfapi/fpdf_parser/cpdf_array_unittest.cpp
index 12a36d921a..efad3c38f6 100644
--- a/core/fpdfapi/fpdf_parser/cpdf_array_unittest.cpp
+++ b/core/fpdfapi/fpdf_parser/cpdf_array_unittest.cpp
@@ -116,7 +116,7 @@ TEST(cpdf_array, Clone) {
         CPDF_Number* obj = new CPDF_Number(elems[i][j]);
         // Starts object number from 1.
         int obj_num = i * kNumOfRowElems + j + 1;
-        obj_holder->InsertIndirectObject(obj_num, obj);
+        obj_holder->ReplaceIndirectObjectIfHigherGeneration(obj_num, obj);
         arr_elem->InsertAt(j, new CPDF_Reference(obj_holder.get(), obj_num),
                            obj_holder.get());
       }
diff --git a/core/fpdfapi/fpdf_parser/cpdf_data_avail.cpp b/core/fpdfapi/fpdf_parser/cpdf_data_avail.cpp
index 94795fd60e..58b69257ad 100644
--- a/core/fpdfapi/fpdf_parser/cpdf_data_avail.cpp
+++ b/core/fpdfapi/fpdf_parser/cpdf_data_avail.cpp
@@ -176,7 +176,7 @@ FX_BOOL CPDF_DataAvail::IsObjectsAvail(
         } else if (!pdfium::ContainsKey(m_ObjectSet, dwNum)) {
           m_ObjectSet.insert(dwNum);
           CPDF_Object* pReferred =
-              m_pDocument->GetIndirectObject(pRef->GetRefObjNum());
+              m_pDocument->GetOrParseIndirectObject(pRef->GetRefObjNum());
           if (pReferred)
             new_obj_array.Add(pReferred);
         }
@@ -1788,8 +1788,10 @@ CPDF_Dictionary* CPDF_DataAvail::GetPage(int index) {
       if (!pPageDict)
         return nullptr;
 
-      if (!m_pDocument->InsertIndirectObject(dwObjNum, pPageDict))
+      if (!m_pDocument->ReplaceIndirectObjectIfHigherGeneration(dwObjNum,
+                                                                pPageDict)) {
         return nullptr;
+      }
       return pPageDict->GetDict();
     }
   }
diff --git a/core/fpdfapi/fpdf_parser/cpdf_document.cpp b/core/fpdfapi/fpdf_parser/cpdf_document.cpp
index 8560660703..a05a24e07f 100644
--- a/core/fpdfapi/fpdf_parser/cpdf_document.cpp
+++ b/core/fpdfapi/fpdf_parser/cpdf_document.cpp
@@ -499,9 +499,9 @@ CPDF_Document::~CPDF_Document() {
 }
 
 void CPDF_Document::LoadDocInternal() {
-  m_LastObjNum = m_pParser->GetLastObjNum();
+  SetLastObjNum(m_pParser->GetLastObjNum());
 
-  CPDF_Object* pRootObj = GetIndirectObject(m_pParser->GetRootObjNum());
+  CPDF_Object* pRootObj = GetOrParseIndirectObject(m_pParser->GetRootObjNum());
   if (!pRootObj)
     return;
 
@@ -509,7 +509,7 @@ void CPDF_Document::LoadDocInternal() {
   if (!m_pRootDict)
     return;
 
-  CPDF_Object* pInfoObj = GetIndirectObject(m_pParser->GetInfoObjNum());
+  CPDF_Object* pInfoObj = GetOrParseIndirectObject(m_pParser->GetInfoObjNum());
   if (pInfoObj)
     m_pInfoDict = pInfoObj->GetDict();
   if (CPDF_Array* pIDArray = m_pParser->GetIDArray()) {
@@ -589,14 +589,14 @@ CPDF_Dictionary* CPDF_Document::GetPage(int iPage) {
 
   if (m_bLinearized && (iPage == m_iFirstPageNo)) {
     if (CPDF_Dictionary* pDict =
-            ToDictionary(GetIndirectObject(m_dwFirstPageObjNum))) {
+            ToDictionary(GetOrParseIndirectObject(m_dwFirstPageObjNum))) {
       return pDict;
     }
   }
 
   int objnum = m_PageList.GetAt(iPage);
   if (objnum) {
-    if (CPDF_Dictionary* pDict = ToDictionary(GetIndirectObject(objnum)))
+    if (CPDF_Dictionary* pDict = ToDictionary(GetOrParseIndirectObject(objnum)))
       return pDict;
   }
 
diff --git a/core/fpdfapi/fpdf_parser/cpdf_indirect_object_holder.cpp b/core/fpdfapi/fpdf_parser/cpdf_indirect_object_holder.cpp
index 33f45a53bf..bb29da5052 100644
--- a/core/fpdfapi/fpdf_parser/cpdf_indirect_object_holder.cpp
+++ b/core/fpdfapi/fpdf_parser/cpdf_indirect_object_holder.cpp
@@ -20,7 +20,8 @@ CPDF_IndirectObjectHolder::~CPDF_IndirectObjectHolder() {
     pair.second->Destroy();
 }
 
-CPDF_Object* CPDF_IndirectObjectHolder::GetIndirectObject(uint32_t objnum) {
+CPDF_Object* CPDF_IndirectObjectHolder::GetOrParseIndirectObject(
+    uint32_t objnum) {
   if (objnum == 0)
     return nullptr;
 
@@ -55,18 +56,9 @@ uint32_t CPDF_IndirectObjectHolder::AddIndirectObject(CPDF_Object* pObj) {
   return m_LastObjNum;
 }
 
-void CPDF_IndirectObjectHolder::ReleaseIndirectObject(uint32_t objnum) {
-  auto it = m_IndirectObjs.find(objnum);
-  if (it == m_IndirectObjs.end() ||
-      it->second->GetObjNum() == CPDF_Object::kInvalidObjNum) {
-    return;
-  }
-  it->second->Destroy();
-  m_IndirectObjs.erase(it);
-}
-
-bool CPDF_IndirectObjectHolder::InsertIndirectObject(uint32_t objnum,
-                                                     CPDF_Object* pObj) {
+bool CPDF_IndirectObjectHolder::ReplaceIndirectObjectIfHigherGeneration(
+    uint32_t objnum,
+    CPDF_Object* pObj) {
   if (!objnum || !pObj)
     return false;
 
@@ -83,3 +75,13 @@ bool CPDF_IndirectObjectHolder::InsertIndirectObject(uint32_t objnum,
   m_LastObjNum = std::max(m_LastObjNum, objnum);
   return true;
 }
+
+void CPDF_IndirectObjectHolder::ReleaseIndirectObject(uint32_t objnum) {
+  auto it = m_IndirectObjs.find(objnum);
+  if (it == m_IndirectObjs.end() ||
+      it->second->GetObjNum() == CPDF_Object::kInvalidObjNum) {
+    return;
+  }
+  it->second->Destroy();
+  m_IndirectObjs.erase(it);
+}
diff --git a/core/fpdfapi/fpdf_parser/cpdf_object_unittest.cpp b/core/fpdfapi/fpdf_parser/cpdf_object_unittest.cpp
index a77f022c40..52b01fe3b4 100644
--- a/core/fpdfapi/fpdf_parser/cpdf_object_unittest.cpp
+++ b/core/fpdfapi/fpdf_parser/cpdf_object_unittest.cpp
@@ -725,13 +725,14 @@ TEST(PDFArrayTest, AddReferenceAndGetObjectAt) {
   // Create two arrays of references by different AddReference() APIs.
   for (size_t i = 0; i < FX_ArraySize(indirect_objs); ++i) {
     // All the indirect objects inserted will be owned by holder.
-    holder->InsertIndirectObject(obj_nums[i], indirect_objs[i]);
+    holder->ReplaceIndirectObjectIfHigherGeneration(obj_nums[i],
+                                                    indirect_objs[i]);
     arr->AddReference(holder.get(), obj_nums[i]);
     arr1->AddReference(holder.get(), indirect_objs[i]);
   }
   // Check indirect objects.
   for (size_t i = 0; i < FX_ArraySize(obj_nums); ++i)
-    EXPECT_EQ(indirect_objs[i], holder->GetIndirectObject(obj_nums[i]));
+    EXPECT_EQ(indirect_objs[i], holder->GetOrParseIndirectObject(obj_nums[i]));
   // Check arrays.
   EXPECT_EQ(arr->GetCount(), arr1->GetCount());
   for (size_t i = 0; i < arr->GetCount(); ++i) {
diff --git a/core/fpdfapi/fpdf_parser/cpdf_parser.cpp b/core/fpdfapi/fpdf_parser/cpdf_parser.cpp
index b2f1a4be3f..26adf7bb13 100644
--- a/core/fpdfapi/fpdf_parser/cpdf_parser.cpp
+++ b/core/fpdfapi/fpdf_parser/cpdf_parser.cpp
@@ -267,7 +267,7 @@ CPDF_Parser::Error CPDF_Parser::SetEncryptHandler() {
     if (CPDF_Dictionary* pEncryptDict = pEncryptObj->AsDictionary()) {
       SetEncryptDictionary(pEncryptDict);
     } else if (CPDF_Reference* pRef = pEncryptObj->AsReference()) {
-      pEncryptObj = m_pDocument->GetIndirectObject(pRef->GetRefObjNum());
+      pEncryptObj = m_pDocument->GetOrParseIndirectObject(pRef->GetRefObjNum());
       if (pEncryptObj)
         SetEncryptDictionary(pEncryptObj->GetDict());
     }
@@ -986,8 +986,10 @@ FX_BOOL CPDF_Parser::LoadCrossRefV5(FX_FILESIZE* pos, FX_BOOL bMainXRef) {
         pObject->Release();
       return FALSE;
     }
-    if (!m_pDocument->InsertIndirectObject(pObject->m_ObjNum, pObject))
+    if (!m_pDocument->ReplaceIndirectObjectIfHigherGeneration(pObject->m_ObjNum,
+                                                              pObject)) {
       return FALSE;
+    }
   }
 
   CPDF_Stream* pStream = pObject->AsStream();
@@ -1230,7 +1232,8 @@ CPDF_StreamAcc* CPDF_Parser::GetObjectStream(uint32_t objnum) {
   if (!m_pDocument)
     return nullptr;
 
-  const CPDF_Stream* pStream = ToStream(m_pDocument->GetIndirectObject(objnum));
+  const CPDF_Stream* pStream =
+      ToStream(m_pDocument->GetOrParseIndirectObject(objnum));
   if (!pStream)
     return nullptr;
 
diff --git a/core/fpdfapi/fpdf_parser/cpdf_reference.cpp b/core/fpdfapi/fpdf_parser/cpdf_reference.cpp
index 007423e5fb..afda50c324 100644
--- a/core/fpdfapi/fpdf_parser/cpdf_reference.cpp
+++ b/core/fpdfapi/fpdf_parser/cpdf_reference.cpp
@@ -63,5 +63,6 @@ void CPDF_Reference::SetRef(CPDF_IndirectObjectHolder* pDoc, uint32_t objnum) {
 }
 
 CPDF_Object* CPDF_Reference::GetDirect() const {
-  return m_pObjList ? m_pObjList->GetIndirectObject(m_RefObjNum) : nullptr;
+  return m_pObjList ? m_pObjList->GetOrParseIndirectObject(m_RefObjNum)
+                    : nullptr;
 }
diff --git a/core/fpdfapi/fpdf_parser/include/cpdf_indirect_object_holder.h b/core/fpdfapi/fpdf_parser/include/cpdf_indirect_object_holder.h
index c29746fdd7..31e0aba5ea 100644
--- a/core/fpdfapi/fpdf_parser/include/cpdf_indirect_object_holder.h
+++ b/core/fpdfapi/fpdf_parser/include/cpdf_indirect_object_holder.h
@@ -22,14 +22,17 @@ class CPDF_IndirectObjectHolder {
   explicit CPDF_IndirectObjectHolder(CPDF_Parser* pParser);
   ~CPDF_IndirectObjectHolder();
 
-  CPDF_Object* GetIndirectObject(uint32_t objnum);
-  uint32_t AddIndirectObject(CPDF_Object* pObj);
+  CPDF_Object* GetOrParseIndirectObject(uint32_t objnum);
   void ReleaseIndirectObject(uint32_t objnum);
 
-  // Takes ownership of |pObj|.
-  bool InsertIndirectObject(uint32_t objnum, CPDF_Object* pObj);
+  // Take ownership of |pObj|.
+  uint32_t AddIndirectObject(CPDF_Object* pObj);
+  bool ReplaceIndirectObjectIfHigherGeneration(uint32_t objnum,
+                                               CPDF_Object* pObj);
 
   uint32_t GetLastObjNum() const { return m_LastObjNum; }
+  void SetLastObjNum(uint32_t objnum) { m_LastObjNum = objnum; }
+
   iterator begin() { return m_IndirectObjs.begin(); }
   const_iterator begin() const { return m_IndirectObjs.begin(); }
   iterator end() { return m_IndirectObjs.end(); }
@@ -37,8 +40,10 @@ class CPDF_IndirectObjectHolder {
 
  protected:
   CPDF_Parser* m_pParser;
-  uint32_t m_LastObjNum;
   std::map<uint32_t, CPDF_Object*> m_IndirectObjs;
+
+ private:
+  uint32_t m_LastObjNum;
 };
 
 #endif  // CORE_FPDFAPI_FPDF_PARSER_INCLUDE_CPDF_INDIRECT_OBJECT_HOLDER_H_