flutter_flutter/third_party/tonic/dart_weak_persistent_value.h
Daco Harkes ccdb6819ce
WeakPersistentHandle migration (#19843)
and roll Dart to 52783837369de45d3372cb6c6b7cdd63e71cd829.
2020-11-03 13:06:53 +01:00

49 lines
1.4 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 LIB_TONIC_DART_WEAK_PERSISTENT_VALUE_H_
#define LIB_TONIC_DART_WEAK_PERSISTENT_VALUE_H_
#include <memory>
#include "third_party/dart/runtime/include/dart_api.h"
#include "tonic/common/macros.h"
namespace tonic {
class DartState;
// DartWeakPersistentValue is a bookkeeping class to help pair calls to
// Dart_NewWeakPersistentHandle with Dart_DeleteWeakPersistentHandle even in
// the case if IsolateGroup shutdown. Consider using this class instead of
// holding a Dart_PersistentHandle directly so that you don't leak the
// Dart_WeakPersistentHandle.
class DartWeakPersistentValue {
public:
DartWeakPersistentValue();
~DartWeakPersistentValue();
Dart_WeakPersistentHandle value() const { return handle_; }
bool is_empty() const { return handle_ == nullptr; }
void Set(DartState* dart_state,
Dart_Handle object,
void* peer,
intptr_t external_allocation_size,
Dart_HandleFinalizer callback);
void Clear();
Dart_Handle Get();
const std::weak_ptr<DartState>& dart_state() const { return dart_state_; }
private:
std::weak_ptr<DartState> dart_state_;
Dart_WeakPersistentHandle handle_;
TONIC_DISALLOW_COPY_AND_ASSIGN(DartWeakPersistentValue);
};
} // namespace tonic
#endif // LIB_TONIC_DART_WEAK_PERSISTENT_VALUE_H_