Return unique_ptrs from CFX_DIBitmap::Clone().

core/fxge/dib/fx_dib_main.cpp

Index: core/fxge/dib/fx_dib_main.cpp
diff --git a/core/fxge/dib/fx_dib_main.cpp b/core/fxge/dib/fx_dib_main.cpp
index 83899553a2bacdb98046b996d124557c33197495..b3576635a0bfb7cd03f2fcd30c537919daf63baf 100644
--- a/core/fxge/dib/fx_dib_main.cpp
+++ b/core/fxge/dib/fx_dib_main.cpp
@@ -13,6 +13,7 @@
 #include <utility>
 
 #include "core/fxcodec/fx_codec.h"
+#include "core/fxcrt/cfx_maybe_owned.h"
 #include "core/fxge/cfx_gemodule.h"
 #include "core/fxge/dib/dib_int.h"
 #include "core/fxge/ge/cfx_cliprgn.h"
@@ -174,15 +175,14 @@ void CFX_DIBitmap::TakeOver(CFX_DIBitmap* pSrcBitmap) {
   m_Pitch = pSrcBitmap->m_Pitch;
 }
 
-CFX_DIBitmap* CFX_DIBSource::Clone(const FX_RECT* pClip) const {
+std::unique_ptr<CFX_DIBitmap> CFX_DIBSource::Clone(const FX_RECT* pClip) const {
   FX_RECT rect(0, 0, m_Width, m_Height);
   if (pClip) {
     rect.Intersect(*pClip);
-    if (rect.IsEmpty()) {
+    if (rect.IsEmpty())
       return nullptr;
-    }
   }
-  std::unique_ptr<CFX_DIBitmap> pNewBitmap(new CFX_DIBitmap);
+  auto pNewBitmap = pdfium::MakeUnique<CFX_DIBitmap>();
   if (!pNewBitmap->Create(rect.Width(), rect.Height(), GetFormat()))
     return nullptr;
 
@@ -211,13 +211,13 @@ CFX_DIBitmap* CFX_DIBSource::Clone(const FX_RECT* pClip) const {
       FXSYS_memcpy(dest_scan, src_scan, copy_len);
     }
   }
-  return pNewBitmap.release();
+  return pNewBitmap;
 }
 
 void CFX_DIBSource::BuildPalette() {
-  if (m_pPalette) {
+  if (m_pPalette)
     return;
-  }
+
   if (GetBPP() == 1) {
     m_pPalette.reset(FX_Alloc(uint32_t, 2));
     if (IsCmykImage()) {
@@ -230,13 +230,11 @@ void CFX_DIBSource::BuildPalette() {
   } else if (GetBPP() == 8) {
     m_pPalette.reset(FX_Alloc(uint32_t, 256));
     if (IsCmykImage()) {
-      for (int i = 0; i < 256; i++) {
+      for (int i = 0; i < 256; i++)
         m_pPalette.get()[i] = 0xff - i;
-      }
     } else {
-      for (int i = 0; i < 256; i++) {
+      for (int i = 0; i < 256; i++)
         m_pPalette.get()[i] = 0xff000000 | (i * 0x10101);
-      }
     }
   }
 }
@@ -665,31 +663,26 @@ const int g_ChannelOffset[] = {0, 2, 1, 0, 0, 1, 2, 3, 3};
 bool CFX_DIBitmap::LoadChannel(FXDIB_Channel destChannel,
                                const CFX_DIBSource* pSrcBitmap,
                                FXDIB_Channel srcChannel) {
-  if (!m_pBuffer) {
+  if (!m_pBuffer)
     return false;
-  }
-  CFX_DIBSource* pSrcClone = (CFX_DIBSource*)pSrcBitmap;
-  CFX_DIBitmap* pDst = this;
-  int destOffset, srcOffset;
+
+  CFX_MaybeOwned<CFX_DIBSource> pSrcClone(
+      const_cast<CFX_DIBSource*>(pSrcBitmap));

[dsinclair, 2016/12/05 20:41:26]

Should we remove the const from the signature?

[Tom Sepez, 2016/12/05 21:38:13]

Ok. Not too many ripples ...

+  int srcOffset;
   if (srcChannel == FXDIB_Alpha) {
-    if (!pSrcBitmap->HasAlpha() && !pSrcBitmap->IsAlphaMask()) {
+    if (!pSrcBitmap->HasAlpha() && !pSrcBitmap->IsAlphaMask())
       return false;
-    }
+
     if (pSrcBitmap->GetBPP() == 1) {
       pSrcClone = pSrcBitmap->CloneConvert(FXDIB_8bppMask);
-      if (!pSrcClone) {
+      if (!pSrcClone)
         return false;
-      }
-    }
-    if (pSrcBitmap->GetFormat() == FXDIB_Argb) {
-      srcOffset = 3;
-    } else {
-      srcOffset = 0;
     }
+    srcOffset = pSrcBitmap->GetFormat() == FXDIB_Argb ? 3 : 0;
   } else {
-    if (pSrcBitmap->IsAlphaMask()) {
+    if (pSrcBitmap->IsAlphaMask())
       return false;
-    }
+
     if (pSrcBitmap->GetBPP() < 24) {
       if (pSrcBitmap->IsCmykImage()) {
         pSrcClone = pSrcBitmap->CloneConvert(
@@ -698,92 +691,63 @@ bool CFX_DIBitmap::LoadChannel(FXDIB_Channel destChannel,
         pSrcClone = pSrcBitmap->CloneConvert(
             (FXDIB_Format)((pSrcBitmap->GetFormat() & 0xff00) | 0x18));
       }
-      if (!pSrcClone) {
+      if (!pSrcClone)
         return false;
-      }
     }
     srcOffset = g_ChannelOffset[srcChannel];
   }
+  int destOffset = 0;
   if (destChannel == FXDIB_Alpha) {
     if (IsAlphaMask()) {
-      if (!ConvertFormat(FXDIB_8bppMask)) {
-        if (pSrcClone != pSrcBitmap) {
-          delete pSrcClone;
-        }
+      if (!ConvertFormat(FXDIB_8bppMask))
         return false;
-      }
-      destOffset = 0;
     } else {
-      destOffset = 0;
-      if (!ConvertFormat(IsCmykImage() ? FXDIB_Cmyka : FXDIB_Argb)) {
-        if (pSrcClone != pSrcBitmap) {
-          delete pSrcClone;
-        }
+      if (!ConvertFormat(IsCmykImage() ? FXDIB_Cmyka : FXDIB_Argb))
         return false;
-      }
-      if (GetFormat() == FXDIB_Argb) {
+
+      if (GetFormat() == FXDIB_Argb)
         destOffset = 3;
-      }
     }
   } else {
-    if (IsAlphaMask()) {
-      if (pSrcClone != pSrcBitmap) {
-        delete pSrcClone;
-      }
+    if (IsAlphaMask())
       return false;
-    }
+
     if (GetBPP() < 24) {
       if (HasAlpha()) {
-        if (!ConvertFormat(IsCmykImage() ? FXDIB_Cmyka : FXDIB_Argb)) {
-          if (pSrcClone != pSrcBitmap) {
-            delete pSrcClone;
-          }
+        if (!ConvertFormat(IsCmykImage() ? FXDIB_Cmyka : FXDIB_Argb))
           return false;
-        }
 #if _FXM_PLATFORM_ == _FXM_PLATFORM_APPLE_
       } else if (!ConvertFormat(IsCmykImage() ? FXDIB_Cmyk : FXDIB_Rgb32)) {
 #else
       } else if (!ConvertFormat(IsCmykImage() ? FXDIB_Cmyk : FXDIB_Rgb)) {
 #endif
-        if (pSrcClone != pSrcBitmap) {
-          delete pSrcClone;
-        }
         return false;
       }
     }
     destOffset = g_ChannelOffset[destChannel];
   }
   if (srcChannel == FXDIB_Alpha && pSrcClone->m_pAlphaMask) {
-    CFX_DIBitmap* pAlphaMask = pSrcClone->m_pAlphaMask;
+    CFX_MaybeOwned<CFX_DIBSource> pAlphaMask(pSrcClone->m_pAlphaMask);
     if (pSrcClone->GetWidth() != m_Width ||
         pSrcClone->GetHeight() != m_Height) {
       if (pAlphaMask) {
         pAlphaMask = pAlphaMask->StretchTo(m_Width, m_Height);
-        if (!pAlphaMask) {
-          if (pSrcClone != pSrcBitmap) {
-            delete pSrcClone;
-          }
+        if (!pAlphaMask)
           return false;
-        }
       }
     }
-    if (pSrcClone != pSrcBitmap) {
-      pSrcClone->m_pAlphaMask = nullptr;
-      delete pSrcClone;
-    }
-    pSrcClone = pAlphaMask;
+    pSrcClone = std::move(pAlphaMask);
     srcOffset = 0;
   } else if (pSrcClone->GetWidth() != m_Width ||
              pSrcClone->GetHeight() != m_Height) {
-    CFX_DIBitmap* pSrcMatched = pSrcClone->StretchTo(m_Width, m_Height);
-    if (pSrcClone != pSrcBitmap) {
-      delete pSrcClone;
-    }
-    if (!pSrcMatched) {
+    std::unique_ptr<CFX_DIBitmap> pSrcMatched =
+        pSrcClone->StretchTo(m_Width, m_Height);
+    if (!pSrcMatched)
       return false;
-    }
-    pSrcClone = pSrcMatched;
+
+    pSrcClone = std::move(pSrcMatched);
   }
+  CFX_DIBitmap* pDst = this;
   if (destChannel == FXDIB_Alpha && m_pAlphaMask) {
     pDst = m_pAlphaMask;
     destOffset = 0;
@@ -799,9 +763,6 @@ bool CFX_DIBitmap::LoadChannel(FXDIB_Channel destChannel,
       src_pos += srcBytes;
     }
   }
-  if (pSrcClone != pSrcBitmap && pSrcClone != pSrcBitmap->m_pAlphaMask) {
-    delete pSrcClone;
-  }
   return true;
 }
 
@@ -865,31 +826,28 @@ bool CFX_DIBitmap::LoadChannel(FXDIB_Channel destChannel, int value) {
 }
 
 bool CFX_DIBitmap::MultiplyAlpha(const CFX_DIBSource* pSrcBitmap) {
-  if (!m_pBuffer) {
+  if (!m_pBuffer)
     return false;
-  }
+
   ASSERT(pSrcBitmap->IsAlphaMask());
-  if (!pSrcBitmap->IsAlphaMask()) {
+  if (!pSrcBitmap->IsAlphaMask())
     return false;
-  }
-  if (!IsAlphaMask() && !HasAlpha()) {
+
+  if (!IsAlphaMask() && !HasAlpha())
     return LoadChannel(FXDIB_Alpha, pSrcBitmap, FXDIB_Alpha);
-  }
-  CFX_DIBitmap* pSrcClone = (CFX_DIBitmap*)pSrcBitmap;
+
+  CFX_MaybeOwned<CFX_DIBitmap> pSrcClone(
+      static_cast<CFX_DIBitmap*>(const_cast<CFX_DIBSource*>(pSrcBitmap)));

[npm, 2016/12/05 20:37:23]

Why 2 casts?

[Tom Sepez, 2016/12/05 21:38:13]

Because a const_cast can't change type, and a static_cast can't change
const-ness, and reinterpret_cast is dangerous as replacement.

   if (pSrcBitmap->GetWidth() != m_Width ||
       pSrcBitmap->GetHeight() != m_Height) {
     pSrcClone = pSrcBitmap->StretchTo(m_Width, m_Height);
-    if (!pSrcClone) {
+    if (!pSrcClone)
       return false;
-    }
   }
   if (IsAlphaMask()) {
-    if (!ConvertFormat(FXDIB_8bppMask)) {
-      if (pSrcClone != pSrcBitmap) {
-        delete pSrcClone;
-      }
+    if (!ConvertFormat(FXDIB_8bppMask))
       return false;
-    }
+
     for (int row = 0; row < m_Height; row++) {
       uint8_t* dest_scan = m_pBuffer + m_Pitch * row;
       uint8_t* src_scan = pSrcClone->m_pBuffer + pSrcClone->m_Pitch * row;
@@ -908,12 +866,9 @@ bool CFX_DIBitmap::MultiplyAlpha(const CFX_DIBSource* pSrcBitmap) {
     }
   } else {
     if (GetFormat() == FXDIB_Argb) {
-      if (pSrcClone->GetBPP() == 1) {
-        if (pSrcClone != pSrcBitmap) {
-          delete pSrcClone;
-        }
+      if (pSrcClone->GetBPP() == 1)
         return false;
-      }
+
       for (int row = 0; row < m_Height; row++) {
         uint8_t* dest_scan = m_pBuffer + m_Pitch * row + 3;
         uint8_t* src_scan = pSrcClone->m_pBuffer + pSrcClone->m_Pitch * row;
@@ -923,12 +878,9 @@ bool CFX_DIBitmap::MultiplyAlpha(const CFX_DIBSource* pSrcBitmap) {
         }
       }
     } else {
-      m_pAlphaMask->MultiplyAlpha(pSrcClone);
+      m_pAlphaMask->MultiplyAlpha(pSrcClone.Get());
     }
   }
-  if (pSrcClone != pSrcBitmap) {
-    delete pSrcClone;
-  }
   return true;
 }
 
@@ -1476,7 +1428,7 @@ CFX_DIBExtractor::CFX_DIBExtractor(const CFX_DIBSource* pSrc) {
     m_pBitmap->CopyPalette(pSrc->GetPalette());
     m_pBitmap->CopyAlphaMask(pSrc->m_pAlphaMask);
   } else {
-    m_pBitmap.reset(pSrc->Clone());
+    m_pBitmap = pSrc->Clone();
   }
 }