mirror of
https://github.com/flutter/flutter.git
synced 2026-02-20 02:29:02 +08:00
29 lines
1.3 KiB
C++
29 lines
1.3 KiB
C++
// Copyright 2013 The Flutter Authors. All rights reserved.
|
|
// Use of this source code is governed by a BSD-style license that can be
|
|
// found in the LICENSE file.
|
|
|
|
#ifndef FLUTTER_SHELL_PLATFORM_EMBEDDER_EMBEDDER_SAFE_ACCESS_H_
|
|
#define FLUTTER_SHELL_PLATFORM_EMBEDDER_EMBEDDER_SAFE_ACCESS_H_
|
|
|
|
#include <type_traits>
|
|
|
|
#define SAFE_ACCESS(pointer, member, default_value) \
|
|
([=]() { \
|
|
if (offsetof(std::remove_pointer<decltype(pointer)>::type, member) + \
|
|
sizeof(pointer->member) <= \
|
|
pointer->struct_size) { \
|
|
return pointer->member; \
|
|
} \
|
|
return static_cast<decltype(pointer->member)>((default_value)); \
|
|
})()
|
|
|
|
/// Checks if the member exists.
|
|
#define SAFE_EXISTS(pointer, member) \
|
|
(SAFE_ACCESS(pointer, member, nullptr) != nullptr)
|
|
|
|
/// Checks if exactly one of member1 or member2 exists.
|
|
#define SAFE_EXISTS_ONE_OF(pointer, member1, member2) \
|
|
(SAFE_EXISTS(pointer, member1) != SAFE_EXISTS(pointer, member2))
|
|
|
|
#endif // FLUTTER_SHELL_PLATFORM_EMBEDDER_EMBEDDER_SAFE_ACCESS_H_
|