Add proper const/non-const versions of CPDF_Array methods.

Instead of having const methods that return non-const pointers.

BUG=pdfium:234

Change-Id: I61495543f67229500dfcf2248e93468e9a9b23cf
Reviewed-on: https://pdfium-review.googlesource.com/32183
Commit-Queue: Lei Zhang <thestig@chromium.org>
Reviewed-by: Henrique Nakashima <hnakashima@chromium.org>

5 files changed, 51 insertions, 14 deletions

diff --git a/core/fpdfapi/parser/cpdf_array.cpp b/core/fpdfapi/parser/cpdf_array.cpp
index 9293101b32..4f802d9e7f 100644
--- a/core/fpdfapi/parser/cpdf_array.cpp
+++ b/core/fpdfapi/parser/cpdf_array.cpp
@@ -87,13 +87,25 @@ CFX_Matrix CPDF_Array::GetMatrix() const {
                     GetNumberAt(3), GetNumberAt(4), GetNumberAt(5));
 }
 
-CPDF_Object* CPDF_Array::GetObjectAt(size_t i) const {
+CPDF_Object* CPDF_Array::GetObjectAt(size_t i) {
   if (i >= m_Objects.size())
     return nullptr;
   return m_Objects[i].get();
 }
 
-CPDF_Object* CPDF_Array::GetDirectObjectAt(size_t i) const {
+const CPDF_Object* CPDF_Array::GetObjectAt(size_t i) const {
+  if (i >= m_Objects.size())
+    return nullptr;
+  return m_Objects[i].get();
+}
+
+CPDF_Object* CPDF_Array::GetDirectObjectAt(size_t i) {
+  if (i >= m_Objects.size())
+    return nullptr;
+  return m_Objects[i]->GetDirect();
+}
+
+const CPDF_Object* CPDF_Array::GetDirectObjectAt(size_t i) const {
   if (i >= m_Objects.size())
     return nullptr;
   return m_Objects[i]->GetDirect();
@@ -123,7 +135,7 @@ float CPDF_Array::GetNumberAt(size_t i) const {
   return m_Objects[i]->GetNumber();
 }
 
-CPDF_Dictionary* CPDF_Array::GetDictAt(size_t i) const {
+CPDF_Dictionary* CPDF_Array::GetDictAt(size_t i) {
   CPDF_Object* p = GetDirectObjectAt(i);
   if (!p)
     return nullptr;
@@ -134,11 +146,30 @@ CPDF_Dictionary* CPDF_Array::GetDictAt(size_t i) const {
   return nullptr;
 }
 
-CPDF_Stream* CPDF_Array::GetStreamAt(size_t i) const {
+const CPDF_Dictionary* CPDF_Array::GetDictAt(size_t i) const {
+  const CPDF_Object* p = GetDirectObjectAt(i);
+  if (!p)
+    return nullptr;
+  if (const CPDF_Dictionary* pDict = p->AsDictionary())
+    return pDict;
+  if (const CPDF_Stream* pStream = p->AsStream())
+    return pStream->GetDict();
+  return nullptr;
+}
+
+CPDF_Stream* CPDF_Array::GetStreamAt(size_t i) {
   return ToStream(GetDirectObjectAt(i));
 }
 
-CPDF_Array* CPDF_Array::GetArrayAt(size_t i) const {
+const CPDF_Stream* CPDF_Array::GetStreamAt(size_t i) const {
+  return ToStream(GetDirectObjectAt(i));
+}
+
+CPDF_Array* CPDF_Array::GetArrayAt(size_t i) {
+  return ToArray(GetDirectObjectAt(i));
+}
+
+const CPDF_Array* CPDF_Array::GetArrayAt(size_t i) const {
   return ToArray(GetDirectObjectAt(i));
 }
 
@@ -204,7 +235,7 @@ bool CPDF_Array::WriteTo(IFX_ArchiveStream* archive) const {
     return false;
 
   for (size_t i = 0; i < GetCount(); ++i) {
-    CPDF_Object* pElement = GetObjectAt(i);
+    const CPDF_Object* pElement = GetObjectAt(i);
     if (!pElement->IsInline()) {
       if (!archive->WriteString(" ") ||
           !archive->WriteDWord(pElement->GetObjNum()) ||
diff --git a/core/fpdfapi/parser/cpdf_array.h b/core/fpdfapi/parser/cpdf_array.h
index 442b85cc80..d980b14507 100644
--- a/core/fpdfapi/parser/cpdf_array.h
+++ b/core/fpdfapi/parser/cpdf_array.h
@@ -37,15 +37,20 @@ class CPDF_Array : public CPDF_Object {
 
   bool IsEmpty() const { return m_Objects.empty(); }
   size_t GetCount() const { return m_Objects.size(); }
-  CPDF_Object* GetObjectAt(size_t index) const;
-  CPDF_Object* GetDirectObjectAt(size_t index) const;
+  CPDF_Object* GetObjectAt(size_t index);
+  const CPDF_Object* GetObjectAt(size_t index) const;
+  CPDF_Object* GetDirectObjectAt(size_t index);
+  const CPDF_Object* GetDirectObjectAt(size_t index) const;
   ByteString GetStringAt(size_t index) const;
   WideString GetUnicodeTextAt(size_t index) const;
   int GetIntegerAt(size_t index) const;
   float GetNumberAt(size_t index) const;
-  CPDF_Dictionary* GetDictAt(size_t index) const;
-  CPDF_Stream* GetStreamAt(size_t index) const;
-  CPDF_Array* GetArrayAt(size_t index) const;
+  CPDF_Dictionary* GetDictAt(size_t index);
+  const CPDF_Dictionary* GetDictAt(size_t index) const;
+  CPDF_Stream* GetStreamAt(size_t index);
+  const CPDF_Stream* GetStreamAt(size_t index) const;
+  CPDF_Array* GetArrayAt(size_t index);
+  const CPDF_Array* GetArrayAt(size_t index) const;
   float GetFloatAt(size_t index) const { return GetNumberAt(index); }
   CFX_Matrix GetMatrix() const;
   CFX_FloatRect GetRect() const;
diff --git a/core/fpdfapi/parser/cpdf_document.cpp b/core/fpdfapi/parser/cpdf_document.cpp
index fea0bddb33..982539cd72 100644
--- a/core/fpdfapi/parser/cpdf_document.cpp
+++ b/core/fpdfapi/parser/cpdf_document.cpp
@@ -491,7 +491,8 @@ CPDF_Pattern* CPDF_Document::LoadPattern(CPDF_Object* pPatternObj,
   return m_pDocPage->GetPattern(pPatternObj, bShading, matrix);
 }
 
-RetainPtr<CPDF_IccProfile> CPDF_Document::LoadIccProfile(CPDF_Stream* pStream) {
+RetainPtr<CPDF_IccProfile> CPDF_Document::LoadIccProfile(
+    const CPDF_Stream* pStream) {
   return m_pDocPage->GetIccProfile(pStream);
 }
 
diff --git a/core/fpdfapi/parser/cpdf_document.h b/core/fpdfapi/parser/cpdf_document.h
index 6357049777..4bbc6939e2 100644
--- a/core/fpdfapi/parser/cpdf_document.h
+++ b/core/fpdfapi/parser/cpdf_document.h
@@ -92,7 +92,7 @@ class CPDF_Document : public CPDF_IndirectObjectHolder {
 
   RetainPtr<CPDF_Image> LoadImageFromPageData(uint32_t dwStreamObjNum);
   RetainPtr<CPDF_StreamAcc> LoadFontFile(CPDF_Stream* pStream);
-  RetainPtr<CPDF_IccProfile> LoadIccProfile(CPDF_Stream* pStream);
+  RetainPtr<CPDF_IccProfile> LoadIccProfile(const CPDF_Stream* pStream);
 
   void LoadDoc();
   void LoadLinearizedDoc(const CPDF_LinearizedHeader* pLinearizationParams);
diff --git a/core/fpdfapi/parser/fpdf_parser_utility.cpp b/core/fpdfapi/parser/fpdf_parser_utility.cpp
index 2c0b0818f1..1dad2a8ab3 100644
--- a/core/fpdfapi/parser/fpdf_parser_utility.cpp
+++ b/core/fpdfapi/parser/fpdf_parser_utility.cpp
@@ -180,7 +180,7 @@ std::ostream& operator<<(std::ostream& buf, const CPDF_Object* pObj) {
       const CPDF_Array* p = pObj->AsArray();
       buf << "[";
       for (size_t i = 0; i < p->GetCount(); i++) {
-        CPDF_Object* pElement = p->GetObjectAt(i);
+        const CPDF_Object* pElement = p->GetObjectAt(i);
         if (pElement && !pElement->IsInline()) {
           buf << " " << pElement->GetObjNum() << " 0 R";
         } else {