Make CPDF_ClipPath have a CPDF_ClipPathData rather than inheriting.

Make Data private to the ClipPath class which manages it
transparently for its callers.  This prevents the callers
from having to remember to make a copy before dirtying the
shared data, since the operations that modify state will do
this under the covers for us.

Review-Url: https://codereview.chromium.org/2301263003

1 files changed, 29 insertions, 8 deletions

diff --git a/core/fpdfapi/fpdf_page/cpdf_clippath.cpp b/core/fpdfapi/fpdf_page/cpdf_clippath.cpp
index e820260131..51ff593a5a 100644
--- a/core/fpdfapi/fpdf_page/cpdf_clippath.cpp
+++ b/core/fpdfapi/fpdf_page/cpdf_clippath.cpp
@@ -8,29 +8,36 @@
 
 #include <utility>
 
+#include "core/fpdfapi/fpdf_page/include/cpdf_path.h"
 #include "core/fpdfapi/fpdf_page/include/cpdf_textobject.h"
 #include "third_party/base/stl_util.h"
 
 #define FPDF_CLIPPATH_MAX_TEXTS 1024
 
+CPDF_ClipPath::CPDF_ClipPath() {}
+
+CPDF_ClipPath::CPDF_ClipPath(const CPDF_ClipPath& that) : m_Ref(that.m_Ref) {}
+
+CPDF_ClipPath::~CPDF_ClipPath() {}
+
 uint32_t CPDF_ClipPath::GetPathCount() const {
-  return pdfium::CollectionSize<uint32_t>(GetObject()->m_PathAndTypeList);
+  return pdfium::CollectionSize<uint32_t>(m_Ref.GetObject()->m_PathAndTypeList);
 }
 
 CPDF_Path CPDF_ClipPath::GetPath(size_t i) const {
-  return GetObject()->m_PathAndTypeList[i].first;
+  return m_Ref.GetObject()->m_PathAndTypeList[i].first;
 }
 
 uint8_t CPDF_ClipPath::GetClipType(size_t i) const {
-  return GetObject()->m_PathAndTypeList[i].second;
+  return m_Ref.GetObject()->m_PathAndTypeList[i].second;
 }
 
 uint32_t CPDF_ClipPath::GetTextCount() const {
-  return pdfium::CollectionSize<uint32_t>(GetObject()->m_TextList);
+  return pdfium::CollectionSize<uint32_t>(m_Ref.GetObject()->m_TextList);
 }
 
 CPDF_TextObject* CPDF_ClipPath::GetText(size_t i) const {
-  return GetObject()->m_TextList[i].get();
+  return m_Ref.GetObject()->m_TextList[i].get();
 }
 
 CFX_FloatRect CPDF_ClipPath::GetClipBox() const {
@@ -73,7 +80,7 @@ CFX_FloatRect CPDF_ClipPath::GetClipBox() const {
 }
 
 void CPDF_ClipPath::AppendPath(CPDF_Path path, uint8_t type, bool bAutoMerge) {
-  CPDF_ClipPathData* pData = GetPrivateCopy();
+  PathData* pData = m_Ref.GetPrivateCopy();
   if (!pData->m_PathAndTypeList.empty() && bAutoMerge) {
     const CPDF_Path& old_path = pData->m_PathAndTypeList.back().first;
     if (old_path.IsRect()) {
@@ -89,7 +96,7 @@ void CPDF_ClipPath::AppendPath(CPDF_Path path, uint8_t type, bool bAutoMerge) {
 
 void CPDF_ClipPath::AppendTexts(
     std::vector<std::unique_ptr<CPDF_TextObject>>* pTexts) {
-  CPDF_ClipPathData* pData = GetPrivateCopy();
+  PathData* pData = m_Ref.GetPrivateCopy();
   if (pData->m_TextList.size() + pTexts->size() <= FPDF_CLIPPATH_MAX_TEXTS) {
     for (size_t i = 0; i < pTexts->size(); i++)
       pData->m_TextList.push_back(std::move((*pTexts)[i]));
@@ -99,7 +106,7 @@ void CPDF_ClipPath::AppendTexts(
 }
 
 void CPDF_ClipPath::Transform(const CFX_Matrix& matrix) {
-  CPDF_ClipPathData* pData = GetPrivateCopy();
+  PathData* pData = m_Ref.GetPrivateCopy();
   for (auto& obj : pData->m_PathAndTypeList)
     obj.first.Transform(&matrix);
   for (auto& text : pData->m_TextList) {
@@ -107,3 +114,17 @@ void CPDF_ClipPath::Transform(const CFX_Matrix& matrix) {
       text->Transform(matrix);
   }
 }
+
+CPDF_ClipPath::PathData::PathData() {}
+
+CPDF_ClipPath::PathData::PathData(const PathData& that) {
+  m_PathAndTypeList = that.m_PathAndTypeList;
+
+  m_TextList.resize(that.m_TextList.size());
+  for (size_t i = 0; i < that.m_TextList.size(); ++i) {
+    if (that.m_TextList[i])
+      m_TextList[i].reset(that.m_TextList[i]->Clone());
+  }
+}
+
+CPDF_ClipPath::PathData::~PathData() {}