Add gfx::GpuMemoryBuffer::YUV_420 and GpuMemoryBufferImplSharedMemory support

content/common/gpu/client/gpu_memory_buffer_impl.cc

Index: content/common/gpu/client/gpu_memory_buffer_impl.cc
diff --git a/content/common/gpu/client/gpu_memory_buffer_impl.cc b/content/common/gpu/client/gpu_memory_buffer_impl.cc
index 208261dd0831e940f8f858b63a4169888c706db8..92f02fcc4305be0b308594ff55f104b55491672e 100644
--- a/content/common/gpu/client/gpu_memory_buffer_impl.cc
+++ b/content/common/gpu/client/gpu_memory_buffer_impl.cc
@@ -77,57 +77,105 @@ GpuMemoryBufferImpl* GpuMemoryBufferImpl::FromClientBuffer(
 }
 
 // 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;
+    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) {
-  base::CheckedNumeric<size_t> s = width;
   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);
-      s /= 2;
-      if (!s.IsValid())
-        return false;
-
-      *stride_in_bytes = s.ValueOrDie();
+      *stride_in_bytes = width / 2;
       return true;
     case RGBA_8888:
     case RGBX_8888:
-    case BGRA_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::NumberOfPlanesForGpuMemoryBufferFormat(
-    gfx::GpuMemoryBuffer::Format format) {
+size_t GpuMemoryBufferImpl::SubsamplingFactor(
+    gfx::GpuMemoryBuffer::Format format,
+    int plane) {
   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:
+    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;
-    default:
-      NOTREACHED();
-      return 0;
+    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 {