gpu/command_buffer/common/buffer.cc

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "gpu/command_buffer/common/buffer.h"
   6
   7 #include "base/logging.h"
   8
   9 #include "base/numerics/safe_math.h"
  10
  11 namespace gpu {
  12 SharedMemoryBufferBacking::SharedMemoryBufferBacking(
  13     scoped_ptr<base::SharedMemory> shared_memory,
  14     size_t size)
  15     : shared_memory_(shared_memory.Pass()), size_(size) {}
  16
  17 SharedMemoryBufferBacking::~SharedMemoryBufferBacking() {}
  18
  19 void* SharedMemoryBufferBacking::GetMemory() const {
  20   return shared_memory_->memory();
  21 }
  22
  23 size_t SharedMemoryBufferBacking::GetSize() const { return size_; }
  24
  25 Buffer::Buffer(scoped_ptr<BufferBacking> backing)
  26     : backing_(backing.Pass()),
  27       memory_(backing_->GetMemory()),
  28       size_(backing_->GetSize()) {
  29   DCHECK(memory_) << "The memory must be mapped to create a Buffer";
  30 }
  31
  32 Buffer::~Buffer() {}
  33
  34 void* Buffer::GetDataAddress(uint32 data_offset, uint32 data_size) const {
  35   base::CheckedNumeric<uint32> end = data_offset;
  36   end += data_size;
  37   if (!end.IsValid() || end.ValueOrDie() > static_cast<uint32>(size_))
  38     return NULL;
  39   return static_cast<uint8*>(memory_) + data_offset;
  40 }
  41
  42 } // namespace gpu