chromium/base/memory/writable_shared_memory_region.h

// Copyright 2018 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef BASE_MEMORY_WRITABLE_SHARED_MEMORY_REGION_H_
#define BASE_MEMORY_WRITABLE_SHARED_MEMORY_REGION_H_

#include "base/base_export.h"
#include "base/check.h"
#include "base/memory/platform_shared_memory_region.h"
#include "base/memory/read_only_shared_memory_region.h"
#include "base/memory/shared_memory_mapping.h"
#include "base/memory/unsafe_shared_memory_region.h"
#include "build/build_config.h"

#include <stdint.h>

namespace base {

// Scoped move-only handle to a region of platform shared memory. The instance
// owns the platform handle it wraps. Mappings created by this region are
// writable. These mappings remain valid even after the region handle is moved
// or destroyed.
//
// This region can be locked to read-only access by converting it to a
// ReadOnlySharedMemoryRegion. However, unlike ReadOnlySharedMemoryRegion and
// UnsafeSharedMemoryRegion, ownership of this region (while writable) is unique
// and may only be transferred, not duplicated.
//
// Unlike ReadOnlySharedMemoryRegion and UnsafeSharedMemoryRegion,
// WritableSharedMemoryRegion doesn't provide GetPlatformHandle() method to
// ensure that the region is never duplicated while writable.
class BASE_EXPORT WritableSharedMemoryRegion { … };

}  // namespace base

#endif  // BASE_MEMORY_WRITABLE_SHARED_MEMORY_REGION_H_