Add CFX_ByteStringC::CharAt() to avoid c_str() and casts

xfa/fee/fde_txtedtengine.cpp

 // Copyright 2014 PDFium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
 #include "xfa/fee/fde_txtedtengine.h"
 
 #include <algorithm>
 #include <memory>
@@ skipping 1585 matching lines @@
     ClearSelection();
     m_Param.pEventSink->On_TextChanged(this, m_ChangeInfo);
     m_Param.pEventSink->On_SelChanged(this);
     SetCaretPos(nSelStart, TRUE);
     return;
   }
 }
 
 IFDE_TxtEdtDoRecord* IFDE_TxtEdtDoRecord::Create(
     const CFX_ByteStringC& bsDoRecord) {
-  const FX_CHAR* lpBuf = bsDoRecord.c_str();
-  int32_t nType = *((int32_t*)lpBuf);
-  switch (nType) {
+  const uint32_t* lpBuf =
+      reinterpret_cast<const uint32_t*>(bsDoRecord.raw_str());
+  switch (*lpBuf) {
     case FDE_TXTEDT_DORECORD_INS:
       return new CFDE_TxtEdtDoRecord_Insert(bsDoRecord);
     case FDE_TXTEDT_DORECORD_DEL:
       return new CFDE_TxtEdtDoRecord_DeleteRange(bsDoRecord);
     default:
       return nullptr;
   }
 }
 
 CFDE_TxtEdtDoRecord_Insert::CFDE_TxtEdtDoRecord_Insert(
@@ skipping 43 matching lines @@
   ArchiveSaver << m_nCaret;
   ArchiveSaver << m_wsInsert;
   int32_t nLength = ArchiveSaver.GetLength();
   const uint8_t* lpSrcBuf = ArchiveSaver.GetBuffer();
   FX_CHAR* lpDstBuf = bsDoRecord.GetBuffer(nLength);
   FXSYS_memcpy(lpDstBuf, lpSrcBuf, nLength);
   bsDoRecord.ReleaseBuffer(nLength);
 }
 void CFDE_TxtEdtDoRecord_Insert::Deserialize(
     const CFX_ByteStringC& bsDoRecord) {
-  CFX_ArchiveLoader ArchiveLoader(
-      reinterpret_cast<const uint8_t*>(bsDoRecord.c_str()),
-      bsDoRecord.GetLength());
+  CFX_ArchiveLoader ArchiveLoader(bsDoRecord.raw_str(), bsDoRecord.GetLength());
   int32_t nType = 0;
   ArchiveLoader >> nType;
   ASSERT(nType == FDE_TXTEDT_DORECORD_INS);
   int32_t nEngine = 0;
   ArchiveLoader >> nEngine;
   m_pEngine = (CFDE_TxtEdtEngine*)(uintptr_t)nEngine;
   ArchiveLoader >> m_nCaret;
   ArchiveLoader >> m_wsInsert;
 }
 CFDE_TxtEdtDoRecord_DeleteRange::CFDE_TxtEdtDoRecord_DeleteRange(
@@ skipping 54 matching lines @@
   ArchiveSaver << m_nCaret;
   ArchiveSaver << m_wsRange;
   int32_t nLength = ArchiveSaver.GetLength();
   const uint8_t* lpSrcBuf = ArchiveSaver.GetBuffer();
   FX_CHAR* lpDstBuf = bsDoRecord.GetBuffer(nLength);
   FXSYS_memcpy(lpDstBuf, lpSrcBuf, nLength);
   bsDoRecord.ReleaseBuffer(nLength);
 }
 void CFDE_TxtEdtDoRecord_DeleteRange::Deserialize(
     const CFX_ByteStringC& bsDoRecord) {
-  CFX_ArchiveLoader ArchiveLoader(
-      reinterpret_cast<const uint8_t*>(bsDoRecord.c_str()),
-      bsDoRecord.GetLength());
+  CFX_ArchiveLoader ArchiveLoader(bsDoRecord.raw_str(), bsDoRecord.GetLength());
   int32_t nType = 0;
   ArchiveLoader >> nType;
   ASSERT(nType == FDE_TXTEDT_DORECORD_DEL);
   int32_t nEngine = 0;
   ArchiveLoader >> nEngine;
   m_pEngine = (CFDE_TxtEdtEngine*)(uintptr_t)nEngine;
   int32_t iSel = 0;
   ArchiveLoader >> iSel;
   m_bSel = !!iSel;
   ArchiveLoader >> m_nIndex;
   ArchiveLoader >> m_nCaret;
   ArchiveLoader >> m_wsRange;
 }