Remove non-const CPDF_PageObjectHolder::GetPageObjectList().

This makes it easier to control modifications to the page object
list.

Bug: pdfium:1051
Change-Id: Ia85c597fa6d39e89041b990b4b6c91e327ef811d
Reviewed-on: https://pdfium-review.googlesource.com/30803
Commit-Queue: Henrique Nakashima <hnakashima@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>

6 files changed, 22 insertions, 17 deletions

diff --git a/core/fpdfapi/page/cpdf_pageobjectholder.cpp b/core/fpdfapi/page/cpdf_pageobjectholder.cpp
index 67b356fc57..310858f7c8 100644
--- a/core/fpdfapi/page/cpdf_pageobjectholder.cpp
+++ b/core/fpdfapi/page/cpdf_pageobjectholder.cpp
@@ -119,3 +119,11 @@ bool CPDF_PageObjectHolder::RemovePageObject(CPDF_PageObject* pPageObj) {
   m_PageObjectList.erase(it);
   return true;
 }
+
+bool CPDF_PageObjectHolder::ErasePageObjectAtIndex(size_t index) {
+  if (index >= m_PageObjectList.size())
+    return false;
+
+  m_PageObjectList.erase(m_PageObjectList.begin() + index);
+  return true;
+}
diff --git a/core/fpdfapi/page/cpdf_pageobjectholder.h b/core/fpdfapi/page/cpdf_pageobjectholder.h
index bf6c476186..a65ccc8129 100644
--- a/core/fpdfapi/page/cpdf_pageobjectholder.h
+++ b/core/fpdfapi/page/cpdf_pageobjectholder.h
@@ -52,7 +52,6 @@ class CPDF_PageObjectHolder {
   void ContinueParse(PauseIndicatorIface* pPause);
   bool IsParsed() const { return m_ParseState == CONTENT_PARSED; }
 
-  CPDF_PageObjectList* GetPageObjectList() { return &m_PageObjectList; }
   const CPDF_PageObjectList* GetPageObjectList() const {
     return &m_PageObjectList;
   }
@@ -61,6 +60,7 @@ class CPDF_PageObjectHolder {
   CPDF_PageObject* GetPageObjectByIndex(size_t index) const;
   void AppendPageObject(std::unique_ptr<CPDF_PageObject> pPageObj);
   bool RemovePageObject(CPDF_PageObject* pPageObj);
+  bool ErasePageObjectAtIndex(size_t index);
 
   const CFX_Matrix& GetLastCTM() const { return m_LastCTM; }
 
diff --git a/core/fpdfapi/page/cpdf_streamcontentparser.cpp b/core/fpdfapi/page/cpdf_streamcontentparser.cpp
index 3b8dac9244..736e91b3c8 100644
--- a/core/fpdfapi/page/cpdf_streamcontentparser.cpp
+++ b/core/fpdfapi/page/cpdf_streamcontentparser.cpp
@@ -793,7 +793,7 @@ void CPDF_StreamContentParser::AddForm(CPDF_Stream* pStream) {
   }
   pFormObj->CalcBoundingBox();
   SetGraphicStates(pFormObj.get(), true, true, true);
-  m_pObjectHolder->GetPageObjectList()->push_back(std::move(pFormObj));
+  m_pObjectHolder->AppendPageObject(std::move(pFormObj));
 }
 
 CPDF_ImageObject* CPDF_StreamContentParser::AddImage(
@@ -836,7 +836,7 @@ CPDF_ImageObject* CPDF_StreamContentParser::AddImageObject(
   pImageObj->CalcBoundingBox();
 
   CPDF_ImageObject* pRet = pImageObj.get();
-  m_pObjectHolder->GetPageObjectList()->push_back(std::move(pImageObj));
+  m_pObjectHolder->AppendPageObject(std::move(pImageObj));
   return pRet;
 }
 
@@ -1095,7 +1095,7 @@ void CPDF_StreamContentParser::Handle_ShadeFill() {
   pObj->m_Right = bbox.right;
   pObj->m_Top = bbox.top;
   pObj->m_Bottom = bbox.bottom;
-  m_pObjectHolder->GetPageObjectList()->push_back(std::move(pObj));
+  m_pObjectHolder->AppendPageObject(std::move(pObj));
 }
 
 void CPDF_StreamContentParser::Handle_SetCharSpace() {
@@ -1242,7 +1242,7 @@ void CPDF_StreamContentParser::AddTextObject(ByteString* pStrs,
       m_ClipTextList.push_back(
           std::unique_ptr<CPDF_TextObject>(pText->Clone()));
     }
-    m_pObjectHolder->GetPageObjectList()->push_back(std::move(pText));
+    m_pObjectHolder->AppendPageObject(std::move(pText));
   }
   if (pKerning && pKerning[nsegs - 1] != 0) {
     if (!pFont->IsVertWriting()) {
@@ -1463,7 +1463,7 @@ void CPDF_StreamContentParser::AddPathObject(int FillType, bool bStroke) {
     pPathObj->m_Matrix = matrix;
     SetGraphicStates(pPathObj.get(), true, false, true);
     pPathObj->CalcBoundingBox();
-    m_pObjectHolder->GetPageObjectList()->push_back(std::move(pPathObj));
+    m_pObjectHolder->AppendPageObject(std::move(pPathObj));
   }
   if (PathClipType) {
     if (!matrix.IsIdentity()) {
diff --git a/core/fpdfapi/render/cpdf_progressiverenderer.cpp b/core/fpdfapi/render/cpdf_progressiverenderer.cpp
index 922e3fd60d..b2d16300d4 100644
--- a/core/fpdfapi/render/cpdf_progressiverenderer.cpp
+++ b/core/fpdfapi/render/cpdf_progressiverenderer.cpp
@@ -63,8 +63,8 @@ void CPDF_ProgressiveRenderer::Continue(PauseIndicatorIface* pPause) {
       m_ClipRect = m_pCurrentLayer->m_Matrix.GetInverse().TransformRect(
           CFX_FloatRect(m_pDevice->GetClipBox()));
     }
-    CPDF_PageObjectList::iterator iter;
-    CPDF_PageObjectList::iterator iterEnd =
+    CPDF_PageObjectList::const_iterator iter;
+    CPDF_PageObjectList::const_iterator iterEnd =
         m_pCurrentLayer->m_pObjectHolder->GetPageObjectList()->end();
     if (m_LastObjectRendered != iterEnd) {
       iter = m_LastObjectRendered;
diff --git a/core/fpdfapi/render/cpdf_progressiverenderer.h b/core/fpdfapi/render/cpdf_progressiverenderer.h
index 5703b42918..400909bda5 100644
--- a/core/fpdfapi/render/cpdf_progressiverenderer.h
+++ b/core/fpdfapi/render/cpdf_progressiverenderer.h
@@ -54,7 +54,7 @@ class CPDF_ProgressiveRenderer {
   CFX_FloatRect m_ClipRect;
   uint32_t m_LayerIndex;
   CPDF_RenderContext::Layer* m_pCurrentLayer;
-  CPDF_PageObjectList::iterator m_LastObjectRendered;
+  CPDF_PageObjectList::const_iterator m_LastObjectRendered;
 };
 
 #endif  // CORE_FPDFAPI_RENDER_CPDF_PROGRESSIVERENDERER_H_
diff --git a/fpdfsdk/fpdf_annot.cpp b/fpdfsdk/fpdf_annot.cpp
index ccc7596401..6504ee7402 100644
--- a/fpdfsdk/fpdf_annot.cpp
+++ b/fpdfsdk/fpdf_annot.cpp
@@ -381,7 +381,7 @@ FPDFAnnot_UpdateObject(FPDF_ANNOTATION annot, FPDF_PAGEOBJECT obj) {
 
   // Check that the object is already in this annotation's object list.
   CPDF_Form* pForm = pAnnot->GetForm();
-  CPDF_PageObjectList* pObjList = pForm->GetPageObjectList();
+  const CPDF_PageObjectList* pObjList = pForm->GetPageObjectList();
   auto it =
       std::find_if(pObjList->begin(), pObjList->end(),
                    [pObj](const std::unique_ptr<CPDF_PageObject>& candidate) {
@@ -432,7 +432,7 @@ FPDFAnnot_AppendObject(FPDF_ANNOTATION annot, FPDF_PAGEOBJECT obj) {
   // Note that an object that came from a different annotation must not be
   // passed here, since an object cannot belong to more than one annotation.
   CPDF_Form* pForm = pAnnot->GetForm();
-  CPDF_PageObjectList* pObjList = pForm->GetPageObjectList();
+  const CPDF_PageObjectList* pObjList = pForm->GetPageObjectList();
   auto it =
       std::find_if(pObjList->begin(), pObjList->end(),
                    [pObj](const std::unique_ptr<CPDF_PageObject>& candidate) {
@@ -442,8 +442,7 @@ FPDFAnnot_AppendObject(FPDF_ANNOTATION annot, FPDF_PAGEOBJECT obj) {
     return false;
 
   // Append the object to the object list.
-  std::unique_ptr<CPDF_PageObject> pPageObjHolder(pObj);
-  pObjList->push_back(std::move(pPageObjHolder));
+  pForm->AppendPageObject(pdfium::WrapUnique(pObj));
 
   // Set the content stream data in the annotation's AP stream.
   UpdateContentStream(pForm, pStream);
@@ -481,7 +480,7 @@ FPDFAnnot_GetObject(FPDF_ANNOTATION annot, int index) {
     pAnnot->SetForm(pStream);
   }
 
-  return pAnnot->GetForm()->GetPageObjectList()->GetPageObjectByIndex(index);
+  return pAnnot->GetForm()->GetPageObjectByIndex(index);
 }
 
 FPDF_EXPORT FPDF_BOOL FPDF_CALLCONV
@@ -501,11 +500,9 @@ FPDFAnnot_RemoveObject(FPDF_ANNOTATION annot, int index) {
   if (!pStream)
     return false;
 
-  CPDF_PageObjectList* pObjList = pAnnot->GetForm()->GetPageObjectList();
-  if (static_cast<size_t>(index) >= pObjList->size())
+  if (!pAnnot->GetForm()->ErasePageObjectAtIndex(index))
     return false;
 
-  pObjList->erase(pObjList->begin() + index);
   UpdateContentStream(pAnnot->GetForm(), pStream);
   return true;
 }