// Copyright 2014 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 "gpu/command_buffer/common/buffer.h"

#include <stddef.h>
#include <stdint.h>

#include "base/format_macros.h"
#include "base/logging.h"
#include "base/numerics/safe_math.h"
#include "base/strings/stringprintf.h"

namespace gpu {
SharedMemoryBufferBacking::SharedMemoryBufferBacking(
    scoped_ptr<base::SharedMemory> shared_memory,
    size_t size)
    : shared_memory_(std::move(shared_memory)), size_(size) {}

SharedMemoryBufferBacking::~SharedMemoryBufferBacking() {}

void* SharedMemoryBufferBacking::GetMemory() const {
  return shared_memory_->memory();
}

size_t SharedMemoryBufferBacking::GetSize() const { return size_; }

Buffer::Buffer(scoped_ptr<BufferBacking> backing)
    : backing_(std::move(backing)),
      memory_(backing_->GetMemory()),
      size_(backing_->GetSize()) {
  DCHECK(memory_) << "The memory must be mapped to create a Buffer";
}

Buffer::~Buffer() {}

void* Buffer::GetDataAddress(uint32_t data_offset, uint32_t data_size) const {
  base::CheckedNumeric<uint32_t> end = data_offset;
  end += data_size;
  if (!end.IsValid() || end.ValueOrDie() > static_cast<uint32_t>(size_))
    return NULL;
  return static_cast<uint8_t*>(memory_) + data_offset;
}

base::trace_event::MemoryAllocatorDumpGuid GetBufferGUIDForTracing(
    uint64_t tracing_process_id,
    int32_t buffer_id) {
  return base::trace_event::MemoryAllocatorDumpGuid(base::StringPrintf(
      "gpu-buffer-x-process/%" PRIx64 "/%d", tracing_process_id, buffer_id));
}

} // namespace gpu