Mark CPDF_Object pointers in pattern code as const.

Change-Id: Id7bf252ebe25c92d26065d1138a445ebb2f78d0b
Reviewed-on: https://pdfium-review.googlesource.com/32187
Reviewed-by: dsinclair <dsinclair@chromium.org>
Reviewed-by: Ryan Harrison <rharrison@chromium.org>
Commit-Queue: Ryan Harrison <rharrison@chromium.org>

11 files changed, 22 insertions, 18 deletions

diff --git a/core/fpdfapi/font/cpdf_font.cpp b/core/fpdfapi/font/cpdf_font.cpp
index ad7eeea264..2201e390ff 100644
--- a/core/fpdfapi/font/cpdf_font.cpp
+++ b/core/fpdfapi/font/cpdf_font.cpp
@@ -315,6 +315,7 @@ CPDF_Font* CPDF_Font::GetStockFont(CPDF_Document* pDoc,
   return pFontGlobals->Set(pDoc, font_id, CPDF_Font::Create(nullptr, pDict));
 }
 
+// static
 std::unique_ptr<CPDF_Font> CPDF_Font::Create(CPDF_Document* pDoc,
                                              CPDF_Dictionary* pFontDict) {
   ByteString type = pFontDict->GetStringFor("Subtype");
diff --git a/core/fpdfapi/font/cpdf_font.h b/core/fpdfapi/font/cpdf_font.h
index 588fb66163..cda86e6ea3 100644
--- a/core/fpdfapi/font/cpdf_font.h
+++ b/core/fpdfapi/font/cpdf_font.h
@@ -66,7 +66,8 @@ class CPDF_Font {
   const ByteString& GetBaseFont() const { return m_BaseFont; }
   CFX_SubstFont* GetSubstFont() const { return m_Font.GetSubstFont(); }
   bool IsEmbedded() const { return IsType3Font() || m_pFontFile != nullptr; }
-  CPDF_Dictionary* GetFontDict() const { return m_pFontDict; }
+  const CPDF_Dictionary* GetFontDict() const { return m_pFontDict; }
+  CPDF_Dictionary* GetFontDict() { return m_pFontDict; }
   bool IsStandardFont() const;
   FXFT_Face GetFace() const { return m_Font.GetFace(); }
   void AppendChar(ByteString* str, uint32_t charcode) const;
diff --git a/core/fpdfapi/page/cpdf_docpagedata.cpp b/core/fpdfapi/page/cpdf_docpagedata.cpp
index 79e148c72a..92dca138cf 100644
--- a/core/fpdfapi/page/cpdf_docpagedata.cpp
+++ b/core/fpdfapi/page/cpdf_docpagedata.cpp
@@ -457,13 +457,13 @@ void CPDF_DocPageData::MaybePurgeIccProfile(const CPDF_Stream* pProfileStream) {
 }
 
 RetainPtr<CPDF_StreamAcc> CPDF_DocPageData::GetFontFileStreamAcc(
-    CPDF_Stream* pFontStream) {
+    const CPDF_Stream* pFontStream) {
   ASSERT(pFontStream);
   auto it = m_FontFileMap.find(pFontStream);
   if (it != m_FontFileMap.end())
     return it->second;
 
-  CPDF_Dictionary* pFontDict = pFontStream->GetDict();
+  const CPDF_Dictionary* pFontDict = pFontStream->GetDict();
   int32_t org_size = pFontDict->GetIntegerFor("Length1") +
                      pFontDict->GetIntegerFor("Length2") +
                      pFontDict->GetIntegerFor("Length3");
@@ -495,7 +495,7 @@ CPDF_CountedColorSpace* CPDF_DocPageData::FindColorSpacePtr(
 }
 
 CPDF_CountedPattern* CPDF_DocPageData::FindPatternPtr(
-    CPDF_Object* pPatternObj) const {
+    const CPDF_Object* pPatternObj) const {
   if (!pPatternObj)
     return nullptr;
 
diff --git a/core/fpdfapi/page/cpdf_docpagedata.h b/core/fpdfapi/page/cpdf_docpagedata.h
index 04b77cf3ed..41a5cd68be 100644
--- a/core/fpdfapi/page/cpdf_docpagedata.h
+++ b/core/fpdfapi/page/cpdf_docpagedata.h
@@ -64,11 +64,12 @@ class CPDF_DocPageData {
   RetainPtr<CPDF_IccProfile> GetIccProfile(const CPDF_Stream* pProfileStream);
   void MaybePurgeIccProfile(const CPDF_Stream* pProfileStream);
 
-  RetainPtr<CPDF_StreamAcc> GetFontFileStreamAcc(CPDF_Stream* pFontStream);
+  RetainPtr<CPDF_StreamAcc> GetFontFileStreamAcc(
+      const CPDF_Stream* pFontStream);
   void MaybePurgeFontFileStreamAcc(const CPDF_Stream* pFontStream);
 
   CPDF_CountedColorSpace* FindColorSpacePtr(const CPDF_Object* pCSObj) const;
-  CPDF_CountedPattern* FindPatternPtr(CPDF_Object* pPatternObj) const;
+  CPDF_CountedPattern* FindPatternPtr(const CPDF_Object* pPatternObj) const;
 
  private:
   using CPDF_CountedFont = CPDF_CountedObject<CPDF_Font>;
diff --git a/core/fpdfapi/page/cpdf_pattern.cpp b/core/fpdfapi/page/cpdf_pattern.cpp
index 88e5dee35c..e2dc4f4f77 100644
--- a/core/fpdfapi/page/cpdf_pattern.cpp
+++ b/core/fpdfapi/page/cpdf_pattern.cpp
@@ -16,7 +16,7 @@ CPDF_Pattern::CPDF_Pattern(CPDF_Document* pDoc,
 CPDF_Pattern::~CPDF_Pattern() {}
 
 void CPDF_Pattern::SetPatternToFormMatrix() {
-  CPDF_Dictionary* pDict = pattern_obj()->GetDict();
+  const CPDF_Dictionary* pDict = pattern_obj()->GetDict();
   m_Pattern2Form = pDict->GetMatrixFor("Matrix");
   m_Pattern2Form.Concat(m_ParentMatrix);
 }
diff --git a/core/fpdfapi/page/cpdf_pattern.h b/core/fpdfapi/page/cpdf_pattern.h
index 307c677775..f1d98922c7 100644
--- a/core/fpdfapi/page/cpdf_pattern.h
+++ b/core/fpdfapi/page/cpdf_pattern.h
@@ -28,7 +28,8 @@ class CPDF_Pattern {
 
   // All the getters that return pointers return non-NULL pointers.
   CPDF_Document* document() const { return m_pDocument.Get(); }
-  CPDF_Object* pattern_obj() const { return m_pPatternObj.Get(); }
+  CPDF_Object* pattern_obj() { return m_pPatternObj.Get(); }
+  const CPDF_Object* pattern_obj() const { return m_pPatternObj.Get(); }
   CFX_Matrix* pattern_to_form() { return &m_Pattern2Form; }
   const CFX_Matrix& parent_matrix() const { return m_ParentMatrix; }
 
diff --git a/core/fpdfapi/page/cpdf_shadingpattern.cpp b/core/fpdfapi/page/cpdf_shadingpattern.cpp
index 76f201f767..52f4e1e10a 100644
--- a/core/fpdfapi/page/cpdf_shadingpattern.cpp
+++ b/core/fpdfapi/page/cpdf_shadingpattern.cpp
@@ -63,15 +63,15 @@ bool CPDF_ShadingPattern::Load() {
   if (m_ShadingType != kInvalidShading)
     return true;
 
-  CPDF_Dictionary* pShadingDict =
+  const CPDF_Dictionary* pShadingDict =
       m_pShadingObj ? m_pShadingObj->GetDict() : nullptr;
   if (!pShadingDict)
     return false;
 
   m_pFunctions.clear();
-  CPDF_Object* pFunc = pShadingDict->GetDirectObjectFor("Function");
+  const CPDF_Object* pFunc = pShadingDict->GetDirectObjectFor("Function");
   if (pFunc) {
-    if (CPDF_Array* pArray = pFunc->AsArray()) {
+    if (const CPDF_Array* pArray = pFunc->AsArray()) {
       m_pFunctions.resize(std::min<size_t>(pArray->GetCount(), 4));
       for (size_t i = 0; i < m_pFunctions.size(); ++i)
         m_pFunctions[i] = CPDF_Function::Load(pArray->GetDirectObjectAt(i));
diff --git a/core/fpdfapi/page/cpdf_shadingpattern.h b/core/fpdfapi/page/cpdf_shadingpattern.h
index bb633f9a4d..3c68c818ea 100644
--- a/core/fpdfapi/page/cpdf_shadingpattern.h
+++ b/core/fpdfapi/page/cpdf_shadingpattern.h
@@ -54,7 +54,7 @@ class CPDF_ShadingPattern : public CPDF_Pattern {
 
   ShadingType GetShadingType() const { return m_ShadingType; }
   bool IsShadingObject() const { return m_bShadingObj; }
-  CPDF_Object* GetShadingObject() const { return m_pShadingObj.Get(); }
+  const CPDF_Object* GetShadingObject() const { return m_pShadingObj.Get(); }
   CPDF_ColorSpace* GetCS() const { return m_pCS.Get(); }
   const std::vector<std::unique_ptr<CPDF_Function>>& GetFuncs() const {
     return m_pFunctions;
@@ -69,7 +69,7 @@ class CPDF_ShadingPattern : public CPDF_Pattern {
 
   ShadingType m_ShadingType = kInvalidShading;
   const bool m_bShadingObj;
-  UnownedPtr<CPDF_Object> m_pShadingObj;
+  UnownedPtr<const CPDF_Object> m_pShadingObj;
 
   // Still keep |m_pCS| as some CPDF_ColorSpace (name object) are not managed
   // as counted objects. Refer to CPDF_DocPageData::GetColorSpace.
diff --git a/core/fpdfapi/page/cpdf_streamcontentparser.cpp b/core/fpdfapi/page/cpdf_streamcontentparser.cpp
index 5f4bdf794d..9dd66f673b 100644
--- a/core/fpdfapi/page/cpdf_streamcontentparser.cpp
+++ b/core/fpdfapi/page/cpdf_streamcontentparser.cpp
@@ -75,7 +75,7 @@ class CPDF_StreamParserAutoClearer {
 CFX_FloatRect GetShadingBBox(CPDF_ShadingPattern* pShading,
                              const CFX_Matrix& matrix) {
   ShadingType type = pShading->GetShadingType();
-  CPDF_Stream* pStream = ToStream(pShading->GetShadingObject());
+  const CPDF_Stream* pStream = ToStream(pShading->GetShadingObject());
   CPDF_ColorSpace* pCS = pShading->GetCS();
   if (!pStream || !pCS)
     return CFX_FloatRect();
diff --git a/core/fpdfapi/page/cpdf_tilingpattern.cpp b/core/fpdfapi/page/cpdf_tilingpattern.cpp
index 5a71baaf7b..3cbfa07fa4 100644
--- a/core/fpdfapi/page/cpdf_tilingpattern.cpp
+++ b/core/fpdfapi/page/cpdf_tilingpattern.cpp
@@ -35,7 +35,7 @@ bool CPDF_TilingPattern::Load() {
   if (m_pForm)
     return true;
 
-  CPDF_Dictionary* pDict = pattern_obj()->GetDict();
+  const CPDF_Dictionary* pDict = pattern_obj()->GetDict();
   if (!pDict)
     return false;
 
diff --git a/core/fxge/skia/fx_skia_device.cpp b/core/fxge/skia/fx_skia_device.cpp
index c0cc4e43d5..b922e49e4a 100644
--- a/core/fxge/skia/fx_skia_device.cpp
+++ b/core/fxge/skia/fx_skia_device.cpp
@@ -1996,8 +1996,8 @@ bool CFX_SkiaDeviceDriver::DrawShading(const CPDF_ShadingPattern* pPattern,
   int nFuncs = pFuncs.size();
   if (nFuncs > 1)  // TODO(caryclark) remove this restriction
     return false;
-  CPDF_Dictionary* pDict = pPattern->GetShadingObject()->GetDict();
-  CPDF_Array* pCoords = pDict->GetArrayFor("Coords");
+  const CPDF_Dictionary* pDict = pPattern->GetShadingObject()->GetDict();
+  const CPDF_Array* pCoords = pDict->GetArrayFor("Coords");
   if (!pCoords && kCoonsPatchMeshShading != shadingType)
     return false;
   // TODO(caryclark) Respect Domain[0], Domain[1]. (Don't know what they do
@@ -2106,7 +2106,7 @@ bool CFX_SkiaDeviceDriver::DrawShading(const CPDF_ShadingPattern* pPattern,
     skPath.transform(inverse);
   } else {
     ASSERT(kCoonsPatchMeshShading == shadingType);
-    CPDF_Stream* pStream = ToStream(pPattern->GetShadingObject());
+    const CPDF_Stream* pStream = ToStream(pPattern->GetShadingObject());
     if (!pStream)
       return false;
     CPDF_MeshStream stream(shadingType, pPattern->GetFuncs(), pStream,