Add IndexInBounds() convenience routine.

Avoid writing |Type| in CollectionSize<Type>() so that index
type can change without rewriting conditions.

Change-Id: I40c94ca39148b379908760ba9b861114b88af7bb
Reviewed-on: https://pdfium-review.googlesource.com/3056
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Tom Sepez <tsepez@chromium.org>

5 files changed, 11 insertions, 16 deletions

diff --git a/xfa/fde/tto/fde_textout.cpp b/xfa/fde/tto/fde_textout.cpp
index c9f5ec84ef..f816176841 100644
--- a/xfa/fde/tto/fde_textout.cpp
+++ b/xfa/fde/tto/fde_textout.cpp
@@ -775,10 +775,7 @@ int32_t CFDE_TTOLine::GetSize() const {
 }
 
 FDE_TTOPIECE* CFDE_TTOLine::GetPtrAt(int32_t index) {
-  if (index < 0 || index >= pdfium::CollectionSize<int32_t>(m_pieces))
-    return nullptr;
-
-  return &m_pieces[index];
+  return pdfium::IndexInBounds(m_pieces, index) ? &m_pieces[index] : nullptr;
 }
 
 void CFDE_TTOLine::RemoveLast(int32_t icount) {
diff --git a/xfa/fde/xml/fde_xml_imp.cpp b/xfa/fde/xml/fde_xml_imp.cpp
index 0959661b26..334410049c 100644
--- a/xfa/fde/xml/fde_xml_imp.cpp
+++ b/xfa/fde/xml/fde_xml_imp.cpp
@@ -652,7 +652,7 @@ int32_t CFDE_XMLInstruction::CountData() const {
 }
 
 bool CFDE_XMLInstruction::GetData(int32_t index, CFX_WideString& wsData) const {
-  if (index < 0 || index >= pdfium::CollectionSize<int32_t>(m_TargetData))
+  if (!pdfium::IndexInBounds(m_TargetData, index))
     return false;
 
   wsData = m_TargetData[index];
@@ -664,10 +664,8 @@ void CFDE_XMLInstruction::AppendData(const CFX_WideString& wsData) {
 }
 
 void CFDE_XMLInstruction::RemoveData(int32_t index) {
-  if (index < 0 || index >= pdfium::CollectionSize<int32_t>(m_TargetData))
-    return;
-
-  m_TargetData.erase(m_TargetData.begin() + index);
+  if (pdfium::IndexInBounds(m_TargetData, index))
+    m_TargetData.erase(m_TargetData.begin() + index);
 }
 
 CFDE_XMLInstruction::~CFDE_XMLInstruction() {}
diff --git a/xfa/fgas/layout/cfx_breakline.cpp b/xfa/fgas/layout/cfx_breakline.cpp
index 65860e4013..562f984ffe 100644
--- a/xfa/fgas/layout/cfx_breakline.cpp
+++ b/xfa/fgas/layout/cfx_breakline.cpp
@@ -17,12 +17,12 @@ int32_t CFX_BreakLine::CountChars() const {
 }
 
 CFX_Char* CFX_BreakLine::GetChar(int32_t index) {
-  ASSERT(index >= 0 && index < pdfium::CollectionSize<int32_t>(m_LineChars));
+  ASSERT(pdfium::IndexInBounds(m_LineChars, index));
   return &m_LineChars[index];
 }
 
 const CFX_Char* CFX_BreakLine::GetChar(int32_t index) const {
-  ASSERT(index >= 0 && index < pdfium::CollectionSize<int32_t>(m_LineChars));
+  ASSERT(pdfium::IndexInBounds(m_LineChars, index));
   return &m_LineChars[index];
 }
 
diff --git a/xfa/fgas/layout/fgas_rtfbreak.cpp b/xfa/fgas/layout/fgas_rtfbreak.cpp
index 37822140c3..68c04a7f64 100644
--- a/xfa/fgas/layout/fgas_rtfbreak.cpp
+++ b/xfa/fgas/layout/fgas_rtfbreak.cpp
@@ -805,8 +805,9 @@ const CFX_BreakPiece* CFX_RTFBreak::GetBreakPieceUnstable(int32_t index) const {
 
   const std::vector<CFX_BreakPiece>& pRTFPieces =
       m_RTFLine[m_iReadyLineIndex].m_LinePieces;
-  if (index < 0 || index >= pdfium::CollectionSize<int32_t>(pRTFPieces))
+  if (!pdfium::IndexInBounds(pRTFPieces, index))
     return nullptr;
+
   return &pRTFPieces[index];
 }
 
diff --git a/xfa/fgas/layout/fgas_textbreak.cpp b/xfa/fgas/layout/fgas_textbreak.cpp
index 8bba780382..c42de45411 100644
--- a/xfa/fgas/layout/fgas_textbreak.cpp
+++ b/xfa/fgas/layout/fgas_textbreak.cpp
@@ -796,11 +796,10 @@ int32_t CFX_TxtBreak::CountBreakPieces() const {
 const CFX_BreakPiece* CFX_TxtBreak::GetBreakPiece(int32_t index) const {
   if (!HasTxtLine())
     return nullptr;
-  if (index < 0 ||
-      index >= pdfium::CollectionSize<int32_t>(
-                   m_TxtLine[m_iReadyLineIndex].m_LinePieces)) {
+
+  if (!pdfium::IndexInBounds(m_TxtLine[m_iReadyLineIndex].m_LinePieces, index))
     return nullptr;
-  }
+
   return &m_TxtLine[m_iReadyLineIndex].m_LinePieces[index];
 }