Fix memory leaking on ClosePage.

core/fpdfapi/fpdf_page/fpdf_page_doc.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/fpdf_page/pageint.h"
 
 #include <algorithm>
 #include <set>
@@ skipping 196 matching lines @@
 
   auto it = m_FontMap.find(pFontDict);
   if (it == m_FontMap.end())
     return;
 
   CPDF_CountedFont* pFontData = it->second;
   if (!pFontData->get())
     return;
 
   pFontData->RemoveRef();
-  if (pFontData->use_count() != 0)
+  if (pFontData->use_count() > 1)
     return;
 
+  // We have font data only in m_FontMap cache. Clean it.
   pFontData->clear();
 }
 
 CPDF_ColorSpace* CPDF_DocPageData::GetColorSpace(
     CPDF_Object* pCSObj,
     const CPDF_Dictionary* pResources) {
   std::set<CPDF_Object*> visited;
   return GetColorSpaceImpl(pCSObj, pResources, &visited);
 }
 
@@ skipping 93 matching lines @@
 
   auto it = m_ColorSpaceMap.find(pColorSpace);
   if (it == m_ColorSpaceMap.end())
     return;
 
   CPDF_CountedColorSpace* pCountedColorSpace = it->second;
   if (!pCountedColorSpace->get())
     return;
 
   pCountedColorSpace->RemoveRef();
-  if (pCountedColorSpace->use_count() != 0)
+  if (pCountedColorSpace->use_count() > 1)
     return;
 
+  // We have item only in m_ColorSpaceMap cache. Clean it.
   pCountedColorSpace->get()->ReleaseCS();
   pCountedColorSpace->reset(nullptr);
 }
 
 CPDF_Pattern* CPDF_DocPageData::GetPattern(CPDF_Object* pPatternObj,
                                            FX_BOOL bShading,
                                            const CFX_Matrix& matrix) {
   if (!pPatternObj)
     return nullptr;
 
@@ skipping 38 matching lines @@
 
   auto it = m_PatternMap.find(pPatternObj);
   if (it == m_PatternMap.end())
     return;
 
   CPDF_CountedPattern* pPattern = it->second;
   if (!pPattern->get())
     return;
 
   pPattern->RemoveRef();
-  if (pPattern->use_count() != 0)
+  if (pPattern->use_count() > 1)
     return;
 
+  // We have item only in m_PatternMap cache. Clean it.
   pPattern->clear();
 }
 
 CPDF_Image* CPDF_DocPageData::GetImage(CPDF_Object* pImageStream) {
   if (!pImageStream)
     return nullptr;
 
   const uint32_t dwImageObjNum = pImageStream->GetObjNum();
   auto it = m_ImageMap.find(dwImageObjNum);
   if (it != m_ImageMap.end())
@@ skipping 15 matching lines @@
 
   auto it = m_ImageMap.find(dwObjNum);
   if (it == m_ImageMap.end())
     return;
 
   CPDF_CountedImage* pCountedImage = it->second;
   if (!pCountedImage)
     return;
 
   pCountedImage->RemoveRef();
-  if (pCountedImage->use_count() != 0)
+  if (pCountedImage->use_count() > 1)
     return;
 
+  // We have item only in m_ImageMap cache. Clean it.
   delete pCountedImage->get();
   delete pCountedImage;
   m_ImageMap.erase(it);
 }
 
 CPDF_IccProfile* CPDF_DocPageData::GetIccProfile(
     CPDF_Stream* pIccProfileStream) {
   if (!pIccProfileStream)
     return nullptr;
 
   auto it = m_IccProfileMap.find(pIccProfileStream);
   if (it != m_IccProfileMap.end())
     return it->second->AddRef();
 
   CPDF_StreamAcc stream;
   stream.LoadAllData(pIccProfileStream, FALSE);
   uint8_t digest[20];
   CRYPT_SHA1Generate(stream.GetData(), stream.GetSize(), digest);
   CFX_ByteString bsDigest(digest, 20);
   auto hash_it = m_HashProfileMap.find(bsDigest);
   if (hash_it != m_HashProfileMap.end()) {
     auto it_copied_stream = m_IccProfileMap.find(hash_it->second);
-    return it_copied_stream->second->AddRef();
+    if (it_copied_stream != m_IccProfileMap.end())
+      return it_copied_stream->second->AddRef();
   }
   CPDF_IccProfile* pProfile =
       new CPDF_IccProfile(stream.GetData(), stream.GetSize());
   CPDF_CountedIccProfile* ipData = new CPDF_CountedIccProfile(pProfile);
   m_IccProfileMap[pIccProfileStream] = ipData;
   m_HashProfileMap[bsDigest] = pIccProfileStream;
   return ipData->AddRef();
 }
 
 void CPDF_DocPageData::ReleaseIccProfile(const CPDF_IccProfile* pIccProfile) {
   ASSERT(pIccProfile);
 
   for (auto it = m_IccProfileMap.begin(); it != m_IccProfileMap.end(); ++it) {
     CPDF_CountedIccProfile* profile = it->second;
     if (profile->get() != pIccProfile)
       continue;
 
     profile->RemoveRef();
-    if (profile->use_count() == 0) {
-      delete profile->get();
-      delete profile;
-      m_IccProfileMap.erase(it);
-      return;
-    }
+    if (profile->use_count() > 1)
+      continue;
+    // We have item only in m_IccProfileMap cache. Clean it.
+    delete profile->get();
+    delete profile;
+    m_IccProfileMap.erase(it);
+    return;
   }
 }
 
 CPDF_StreamAcc* CPDF_DocPageData::GetFontFileStreamAcc(
     CPDF_Stream* pFontStream) {
   ASSERT(pFontStream);
 
   auto it = m_FontFileMap.find(pFontStream);
   if (it != m_FontFileMap.end())
     return it->second->AddRef();
@@ skipping 19 matching lines @@
 
   auto it = m_FontFileMap.find(pFontStream);
   if (it == m_FontFileMap.end())
     return;
 
   CPDF_CountedStreamAcc* pCountedStream = it->second;
   if (!pCountedStream)
     return;
 
   pCountedStream->RemoveRef();
-  if (pCountedStream->use_count() != 0)
+  if (pCountedStream->use_count() > 1)
     return;
 
+  // We have item only in m_FontFileMap cache. Clean it.
   delete pCountedStream->get();
   delete pCountedStream;
   m_FontFileMap.erase(it);
 }
 
 CPDF_CountedColorSpace* CPDF_DocPageData::FindColorSpacePtr(
     CPDF_Object* pCSObj) const {
   if (!pCSObj)
     return nullptr;
 
   auto it = m_ColorSpaceMap.find(pCSObj);
   return it != m_ColorSpaceMap.end() ? it->second : nullptr;
 }
 
 CPDF_CountedPattern* CPDF_DocPageData::FindPatternPtr(
     CPDF_Object* pPatternObj) const {
   if (!pPatternObj)
     return nullptr;
 
   auto it = m_PatternMap.find(pPatternObj);
   return it != m_PatternMap.end() ? it->second : nullptr;
 }