Use smart pointers for various Jbig2 decoding contexts

core/fxcodec/jbig2/JBig2_Context.cpp

Index: core/fxcodec/jbig2/JBig2_Context.cpp
diff --git a/core/fxcodec/jbig2/JBig2_Context.cpp b/core/fxcodec/jbig2/JBig2_Context.cpp
index 8dde290be6df11c362579eb35424f198156fa573..669393e64ec4951010877827f20d8ef42fa749c1 100644
--- a/core/fxcodec/jbig2/JBig2_Context.cpp
+++ b/core/fxcodec/jbig2/JBig2_Context.cpp
@@ -45,19 +45,6 @@ size_t GetRefAggContextSize(FX_BOOL val) {
 // difference for typical JBIG2 documents.
 static const int kSymbolDictCacheMaxSize = 2;
 
-CJBig2_Context* CJBig2_Context::CreateContext(
-    CPDF_StreamAcc* pGlobalStream,
-    CPDF_StreamAcc* pSrcStream,
-    std::list<CJBig2_CachePair>* pSymbolDictCache,
-    IFX_Pause* pPause) {
-  return new CJBig2_Context(pGlobalStream, pSrcStream, pSymbolDictCache, pPause,
-                            false);
-}
-
-void CJBig2_Context::DestroyContext(CJBig2_Context* pContext) {
-  delete pContext;
-}
-
 CJBig2_Context::CJBig2_Context(CPDF_StreamAcc* pGlobalStream,
                                CPDF_StreamAcc* pSrcStream,
                                std::list<CJBig2_CachePair>* pSymbolDictCache,
@@ -69,26 +56,17 @@ CJBig2_Context::CJBig2_Context(CPDF_StreamAcc* pGlobalStream,
       m_PauseStep(10),
       m_pPause(pPause),
       m_ProcessingStatus(FXCODEC_STATUS_FRAME_READY),
-      m_gbContext(nullptr),
       m_dwOffset(0),
       m_pSymbolDictCache(pSymbolDictCache),
       m_bIsGlobal(bIsGlobal) {
   if (pGlobalStream && (pGlobalStream->GetSize() > 0)) {
-    m_pGlobalContext = new CJBig2_Context(nullptr, pGlobalStream,
-                                          pSymbolDictCache, pPause, true);
-  } else {
-    m_pGlobalContext = nullptr;
+    m_pGlobalContext.reset(new CJBig2_Context(nullptr, pGlobalStream,
+                                              pSymbolDictCache, pPause, true));
   }
-
   m_pStream.reset(new CJBig2_BitStream(pSrcStream));
 }
 
-CJBig2_Context::~CJBig2_Context() {
-  FX_Free(m_gbContext);
-  m_gbContext = nullptr;
-  delete m_pGlobalContext;
-  m_pGlobalContext = nullptr;
-}
+CJBig2_Context::~CJBig2_Context() {}
 
 int32_t CJBig2_Context::decode_SquentialOrgnazation(IFX_Pause* pPause) {
   int32_t nRet;
@@ -1108,13 +1086,14 @@ int32_t CJBig2_Context::parseGenericRegion(CJBig2_Segment* pSegment,
   if (m_pGRD->MMR == 0) {
     if (!m_gbContext) {
       const size_t size = GetHuffContextSize(m_pGRD->GBTEMPLATE);
-      m_gbContext = FX_Alloc(JBig2ArithCtx, size);
-      JBIG2_memset(m_gbContext, 0, sizeof(JBig2ArithCtx) * size);
+      m_gbContext.reset(FX_Alloc(JBig2ArithCtx, size));
+      JBIG2_memset(m_gbContext.get(), 0, sizeof(JBig2ArithCtx) * size);
     }
     if (!m_pArithDecoder) {
       m_pArithDecoder.reset(new CJBig2_ArithDecoder(m_pStream.get()));
       m_ProcessingStatus = m_pGRD->Start_decode_Arith(
-          &pSegment->m_Result.im, m_pArithDecoder.get(), m_gbContext, pPause);
+          &pSegment->m_Result.im, m_pArithDecoder.get(), m_gbContext.get(),
+          pPause);
     } else {
       m_ProcessingStatus = m_pGRD->Continue_decode(pPause);
     }
@@ -1136,8 +1115,7 @@ int32_t CJBig2_Context::parseGenericRegion(CJBig2_Segment* pSegment,
       return JBIG2_SUCCESS;
     } else {
       m_pArithDecoder.reset();
-      FX_Free(m_gbContext);
-      m_gbContext = nullptr;
+      m_gbContext.reset();
       if (!pSegment->m_Result.im) {
         m_ProcessingStatus = FXCODEC_STATUS_ERROR;
         m_pGRD.reset();