Properly release caches in CPDF_DocRenderData

core/fpdfapi/render/fpdf_render.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 "core/fpdfapi/render/render_int.h"
 
 #include <memory>
 
@@ skipping 62 matching lines @@
     pCache = new CPDF_CountedObject<CPDF_Type3Cache>(pType3);
     m_Type3FaceMap[pFont] = pCache;
   } else {
     pCache = it->second;
   }
   return pCache->AddRef();
 }
 
 void CPDF_DocRenderData::ReleaseCachedType3(CPDF_Type3Font* pFont) {
   auto it = m_Type3FaceMap.find(pFont);
-  if (it != m_Type3FaceMap.end())
+  if (it != m_Type3FaceMap.end()) {
     it->second->RemoveRef();
+    if (it->second->use_count() < 2) {
+      delete it->second->get();
+      delete it->second;
+      m_Type3FaceMap.erase(it);
+    }
+  }
 }
 
 CPDF_RenderOptions::CPDF_RenderOptions()
     : m_ColorMode(RENDER_COLOR_NORMAL),
       m_Flags(RENDER_CLEARTYPE),
       m_Interpolation(0),
       m_AddFlags(0),
       m_pOCContext(nullptr),
       m_dwLimitCacheSize(1024 * 1024 * 100),
       m_HalftoneLimit(-1),
@@ skipping 1048 matching lines @@
       }
     }
   }
 
   pTransfer->m_bIdentity = bIdentity;
   return pTransferCounter->AddRef();
 }
 
 void CPDF_DocRenderData::ReleaseTransferFunc(CPDF_Object* pObj) {
   auto it = m_TransferFuncMap.find(pObj);
-  if (it != m_TransferFuncMap.end())
+  if (it != m_TransferFuncMap.end()) {
     it->second->RemoveRef();
+    if (it->second->use_count() < 2) {
+      delete it->second->get();
+      delete it->second;
+      m_TransferFuncMap.erase(it);
+    }
+  }
 }
 
 CPDF_DeviceBuffer::CPDF_DeviceBuffer()
     : m_pDevice(nullptr), m_pContext(nullptr), m_pObject(nullptr) {}
 
 CPDF_DeviceBuffer::~CPDF_DeviceBuffer() {}
 
 bool CPDF_DeviceBuffer::Initialize(CPDF_RenderContext* pContext,
                                    CFX_RenderDevice* pDevice,
                                    FX_RECT* pRect,
@@ skipping 116 matching lines @@
     m_pDevice->StretchDIBits(m_pBitmapDevice->GetBitmap(), m_Rect.left,
                              m_Rect.top, m_Rect.Width(), m_Rect.Height());
   }
 }
 
 #if defined _SKIA_SUPPORT_
 void CPDF_RenderStatus::DebugVerifyDeviceIsPreMultiplied() const {
   m_pDevice->DebugVerifyBitmapIsPreMultiplied();
 }
 #endif