Add gfx::GpuMemoryBuffer::YUV_420 and GpuMemoryBufferImplSharedMemory support

content/common/gpu/client/gpu_memory_buffer_impl.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/common/gpu/client/gpu_memory_buffer_impl.h"
 
 #include "base/logging.h"
 #include "base/numerics/safe_math.h"
 #include "content/common/gpu/client/gpu_memory_buffer_impl_shared_memory.h"
 #include "ui/gl/gl_bindings.h"
@@ skipping 59 matching lines @@
   }
 }
 
 // static
 GpuMemoryBufferImpl* GpuMemoryBufferImpl::FromClientBuffer(
     ClientBuffer buffer) {
   return reinterpret_cast<GpuMemoryBufferImpl*>(buffer);
 }
 
 // static
-bool GpuMemoryBufferImpl::StrideInBytes(size_t width,
-                                        Format format,
-                                        size_t* stride_in_bytes) {
-  base::CheckedNumeric<size_t> s = width;
-  switch (format) {
-    case ATCIA:
-    case DXT5:
-      *stride_in_bytes = width;
-      return true;
-    case ATC:
-    case DXT1:
-    case ETC1:
-      DCHECK_EQ(width % 2, 0U);
-      s /= 2;
-      if (!s.IsValid())
-        return false;
-
-      *stride_in_bytes = s.ValueOrDie();
-      return true;
-    case RGBA_8888:
-    case RGBX_8888:
-    case BGRA_8888:
-      s *= 4;
-      if (!s.IsValid())
-        return false;
-
-      *stride_in_bytes = s.ValueOrDie();
-      return true;
-  }
-
-  NOTREACHED();
-  return false;
-}
-
-// static
 size_t GpuMemoryBufferImpl::NumberOfPlanesForGpuMemoryBufferFormat(
     gfx::GpuMemoryBuffer::Format format) {
   switch (format) {
     case gfx::GpuMemoryBuffer::Format::ATC:
     case gfx::GpuMemoryBuffer::Format::ATCIA:
     case gfx::GpuMemoryBuffer::Format::DXT1:
     case gfx::GpuMemoryBuffer::Format::DXT5:
     case gfx::GpuMemoryBuffer::Format::ETC1:
     case gfx::GpuMemoryBuffer::Format::RGBA_8888:
     case gfx::GpuMemoryBuffer::Format::RGBX_8888:
     case gfx::GpuMemoryBuffer::Format::BGRA_8888:
       return 1;
-    default:
-      NOTREACHED();
-      return 0;
+    case gfx::GpuMemoryBuffer::Format::YUV_420:
+      return 3;
   }
+  NOTREACHED();
+  return 0;
+}
+
+// static
+bool GpuMemoryBufferImpl::StrideInBytes(size_t width,
+                                        Format format,
+                                        int plane,
+                                        size_t* stride_in_bytes) {
+  switch (format) {
+    case ATCIA:
+    case DXT5:
+      DCHECK_EQ(plane, 0);
+      *stride_in_bytes = width;
+      return true;
+    case ATC:
+    case DXT1:
+    case ETC1:
+      DCHECK_EQ(plane, 0);
+      DCHECK_EQ(width % 2, 0U);
+      *stride_in_bytes = width / 2;
+      return true;
+    case RGBA_8888:
+    case RGBX_8888:
+    case BGRA_8888: {
+      base::CheckedNumeric<size_t> s = width;
+      DCHECK_EQ(plane, 0);
+      s *= 4;
+      if (!s.IsValid())
+        return false;
+      *stride_in_bytes = s.ValueOrDie();
+      return true;
+    }
+    case YUV_420: {
+      DCHECK_EQ(width % 2, 0u);
+      *stride_in_bytes = width / SubsamplingFactor(format, plane);
+      return true;
+    }
+  }
+  NOTREACHED();
+  return false;
+}
+
+// static
+size_t GpuMemoryBufferImpl::SubsamplingFactor(
+    gfx::GpuMemoryBuffer::Format format,
+    int plane) {
+  switch (format) {
+    case gfx::GpuMemoryBuffer::ATC:
+    case gfx::GpuMemoryBuffer::ATCIA:
+    case gfx::GpuMemoryBuffer::DXT1:
+    case gfx::GpuMemoryBuffer::DXT5:
+    case gfx::GpuMemoryBuffer::ETC1:
+    case gfx::GpuMemoryBuffer::RGBA_8888:
+    case gfx::GpuMemoryBuffer::RGBX_8888:
+    case gfx::GpuMemoryBuffer::BGRA_8888:
+      return 1;
+    case gfx::GpuMemoryBuffer::YUV_420: {
+      static size_t factor[] = {1, 2, 2};
+      DCHECK_LT(static_cast<size_t>(plane), arraysize(factor));
+      return factor[plane];
+    }
+  }
+  NOTREACHED();
+  return 0;
+}
+
+// static
+bool GpuMemoryBufferImpl::TotalBufferSizeInBytes(
+    const gfx::Size& size,
+    gfx::GpuMemoryBuffer::Format format,
+    size_t* total_size_in_bytes) {
+  base::CheckedNumeric<size_t> size_in_bytes = 0u;
+  for (size_t i = 0; i < NumberOfPlanesForGpuMemoryBufferFormat(format); ++i) {
+    size_t stride_in_bytes = 0;
+    if (!StrideInBytes(size.width(), format, i, &stride_in_bytes))
+      return false;
+    size_in_bytes +=
+        stride_in_bytes * (size.height() / SubsamplingFactor(format, i));

[reveman, 2015/04/07 19:03:25]

This multiplication can overflow. You need another CheckedNumeric here to
protect against it.

[emircan, 2015/04/07 20:08:12]

Done.

+    if (!size_in_bytes.IsValid())
+      return false;
+  }
+  *total_size_in_bytes = size_in_bytes.ValueOrDie();
+  return true;
 }
 
 gfx::GpuMemoryBuffer::Format GpuMemoryBufferImpl::GetFormat() const {
   return format_;
 }
 
 bool GpuMemoryBufferImpl::IsMapped() const {
   return mapped_;
 }
 
 ClientBuffer GpuMemoryBufferImpl::AsClientBuffer() {
   return reinterpret_cast<ClientBuffer>(this);
 }
 
 }  // namespace content