diff -r 000000000000 -r 6474c204b198 gfx/ipc/SharedDIBSurface.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gfx/ipc/SharedDIBSurface.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,65 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "SharedDIBSurface.h"
+
+#include "cairo.h"
+
+namespace mozilla {
+namespace gfx {
+
+static const cairo_user_data_key_t SHAREDDIB_KEY = {0};
+
+static const long kBytesPerPixel = 4;
+
+bool
+SharedDIBSurface::Create(HDC adc, uint32_t aWidth, uint32_t aHeight,
+                         bool aTransparent)
+{
+  nsresult rv = mSharedDIB.Create(adc, aWidth, aHeight, aTransparent);
+  if (NS_FAILED(rv) || !mSharedDIB.IsValid())
+    return false;
+
+  InitSurface(aWidth, aHeight, aTransparent);
+  return true;
+}
+
+bool
+SharedDIBSurface::Attach(Handle aHandle, uint32_t aWidth, uint32_t aHeight,
+                         bool aTransparent)
+{
+  nsresult rv = mSharedDIB.Attach(aHandle, aWidth, aHeight, aTransparent);
+  if (NS_FAILED(rv) || !mSharedDIB.IsValid())
+    return false;
+
+  InitSurface(aWidth, aHeight, aTransparent);
+  return true;
+}
+
+void
+SharedDIBSurface::InitSurface(uint32_t aWidth, uint32_t aHeight,
+                              bool aTransparent)
+{
+  long stride = long(aWidth * kBytesPerPixel);
+  unsigned char* data = reinterpret_cast<unsigned char*>(mSharedDIB.GetBits());
+
+  gfxImageFormat format = aTransparent ? gfxImageFormat::ARGB32 : gfxImageFormat::RGB24;
+
+  gfxImageSurface::InitWithData(data, gfxIntSize(aWidth, aHeight),
+                                stride, format);
+
+  cairo_surface_set_user_data(mSurface, &SHAREDDIB_KEY, this, nullptr);
+}
+
+bool
+SharedDIBSurface::IsSharedDIBSurface(gfxASurface* aSurface)
+{
+  return aSurface &&
+    aSurface->GetType() == gfxSurfaceType::Image &&
+    aSurface->GetData(&SHAREDDIB_KEY);
+}
+
+} // namespace gfx
+} // namespace mozilla