Refcount all CFX_DIBSources (and subclasses) all the time.

There are currently several ownership models for these objects,
including ad-hoc logic for sharing and deletion, and the
now-redundant CFX_DIBitmapRef externally-counted handle to the DIBs.

Replace them all with the internal refcount scheme.

Change-Id: I2db399dfc19219eda384f94cc989353b78ce2872
Reviewed-on: https://pdfium-review.googlesource.com/3166
Reviewed-by: dsinclair <dsinclair@chromium.org>
Commit-Queue: dsinclair <dsinclair@chromium.org>

1 files changed, 29 insertions, 37 deletions

diff --git a/core/fpdfapi/render/cpdf_imagecacheentry.cpp b/core/fpdfapi/render/cpdf_imagecacheentry.cpp
index 82b6117f86..751b3eb4b4 100644
--- a/core/fpdfapi/render/cpdf_imagecacheentry.cpp
+++ b/core/fpdfapi/render/cpdf_imagecacheentry.cpp
@@ -31,30 +31,27 @@ CPDF_ImageCacheEntry::CPDF_ImageCacheEntry(CPDF_Document* pDoc,
 
 CPDF_ImageCacheEntry::~CPDF_ImageCacheEntry() {}
 
-void CPDF_ImageCacheEntry::Reset(const CFX_DIBitmap* pBitmap) {
-  m_pCachedBitmap.reset();
+void CPDF_ImageCacheEntry::Reset(const CFX_RetainPtr<CFX_DIBitmap>& pBitmap) {
+  m_pCachedBitmap.Reset();
   if (pBitmap)
     m_pCachedBitmap = pBitmap->Clone();
   CalcSize();
 }
 
-static uint32_t FPDF_ImageCache_EstimateImageSize(const CFX_DIBSource* pDIB) {
+static uint32_t FPDF_ImageCache_EstimateImageSize(
+    const CFX_RetainPtr<CFX_DIBSource>& pDIB) {
   return pDIB && pDIB->GetBuffer()
              ? (uint32_t)pDIB->GetHeight() * pDIB->GetPitch() +
                    (uint32_t)pDIB->GetPaletteSize() * 4
              : 0;
 }
 
-CFX_DIBSource* CPDF_ImageCacheEntry::DetachBitmap() {
-  CFX_DIBSource* pDIBSource = m_pCurBitmap;
-  m_pCurBitmap = nullptr;
-  return pDIBSource;
+CFX_RetainPtr<CFX_DIBSource> CPDF_ImageCacheEntry::DetachBitmap() {
+  return std::move(m_pCurBitmap);
 }
 
-CFX_DIBSource* CPDF_ImageCacheEntry::DetachMask() {
-  CFX_DIBSource* pDIBSource = m_pCurMask;
-  m_pCurMask = nullptr;
-  return pDIBSource;
+CFX_RetainPtr<CFX_DIBSource> CPDF_ImageCacheEntry::DetachMask() {
+  return std::move(m_pCurMask);
 }
 
 int CPDF_ImageCacheEntry::StartGetCachedBitmap(CPDF_Dictionary* pFormResources,
@@ -66,25 +63,23 @@ int CPDF_ImageCacheEntry::StartGetCachedBitmap(CPDF_Dictionary* pFormResources,
                                                int32_t downsampleWidth,
                                                int32_t downsampleHeight) {
   if (m_pCachedBitmap) {
-    m_pCurBitmap = m_pCachedBitmap.get();
-    m_pCurMask = m_pCachedMask.get();
+    m_pCurBitmap = m_pCachedBitmap;
+    m_pCurMask = m_pCachedMask;
     return 1;
   }
   if (!pRenderStatus)
     return 0;
 
   m_pRenderStatus = pRenderStatus;
-  m_pCurBitmap = new CPDF_DIBSource;
-  int ret =
-      ((CPDF_DIBSource*)m_pCurBitmap)
-          ->StartLoadDIBSource(m_pDocument, m_pStream, true, pFormResources,
-                               pPageResources, bStdCS, GroupFamily, bLoadMask);
+  m_pCurBitmap = pdfium::MakeRetain<CPDF_DIBSource>();
+  int ret = m_pCurBitmap.As<CPDF_DIBSource>()->StartLoadDIBSource(
+      m_pDocument, m_pStream, true, pFormResources, pPageResources, bStdCS,
+      GroupFamily, bLoadMask);
   if (ret == 2)
     return ret;
 
   if (!ret) {
-    delete m_pCurBitmap;
-    m_pCurBitmap = nullptr;
+    m_pCurBitmap.Reset();
     return 0;
   }
   ContinueGetCachedBitmap();
@@ -92,44 +87,41 @@ int CPDF_ImageCacheEntry::StartGetCachedBitmap(CPDF_Dictionary* pFormResources,
 }
 
 void CPDF_ImageCacheEntry::ContinueGetCachedBitmap() {
-  m_MatteColor = ((CPDF_DIBSource*)m_pCurBitmap)->GetMatteColor();
-  m_pCurMask = ((CPDF_DIBSource*)m_pCurBitmap)->DetachMask();
+  m_MatteColor = m_pCurBitmap.As<CPDF_DIBSource>()->GetMatteColor();
+  m_pCurMask = m_pCurBitmap.As<CPDF_DIBSource>()->DetachMask();
   CPDF_RenderContext* pContext = m_pRenderStatus->GetContext();
   CPDF_PageRenderCache* pPageRenderCache = pContext->GetPageCache();
   m_dwTimeCount = pPageRenderCache->GetTimeCount();
   if (m_pCurBitmap->GetPitch() * m_pCurBitmap->GetHeight() <
       FPDF_HUGE_IMAGE_SIZE) {
     m_pCachedBitmap = m_pCurBitmap->Clone();
-    delete m_pCurBitmap;
-    m_pCurBitmap = nullptr;
+    m_pCurBitmap.Reset();
   } else {
-    m_pCachedBitmap = pdfium::WrapUnique<CFX_DIBSource>(m_pCurBitmap);
+    m_pCachedBitmap = m_pCurBitmap;
   }
   if (m_pCurMask) {
     m_pCachedMask = m_pCurMask->Clone();
-    delete m_pCurMask;
-    m_pCurMask = nullptr;
+    m_pCurMask.Reset();
   }
-  m_pCurBitmap = m_pCachedBitmap.get();
-  m_pCurMask = m_pCachedMask.get();
+  m_pCurBitmap = m_pCachedBitmap;
+  m_pCurMask = m_pCachedMask;
   CalcSize();
 }
 
 int CPDF_ImageCacheEntry::Continue(IFX_Pause* pPause) {
-  int ret = ((CPDF_DIBSource*)m_pCurBitmap)->ContinueLoadDIBSource(pPause);
-  if (ret == 2)
-    return ret;
-
+  int ret = m_pCurBitmap.As<CPDF_DIBSource>()->ContinueLoadDIBSource(pPause);
   if (!ret) {
-    delete m_pCurBitmap;
-    m_pCurBitmap = nullptr;
+    m_pCurBitmap.Reset();
     return 0;
   }
+  if (ret == 2)
+    return ret;
+
   ContinueGetCachedBitmap();
   return 0;
 }
 
 void CPDF_ImageCacheEntry::CalcSize() {
-  m_dwCacheSize = FPDF_ImageCache_EstimateImageSize(m_pCachedBitmap.get()) +
-                  FPDF_ImageCache_EstimateImageSize(m_pCachedMask.get());
+  m_dwCacheSize = FPDF_ImageCache_EstimateImageSize(m_pCachedBitmap) +
+                  FPDF_ImageCache_EstimateImageSize(m_pCachedMask);
 }