blob: 5986c57def848909d981a9b2f013867aaa13364b [file] [log] [blame]
// Copyright 2013 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.
namespace ios {
class SupportsUserDataInternal;
// This is a helper for classes that want to allow users to stash random data by
// key. At destruction all the objects will be destructed.
class SupportsUserData {
// Derive from this class and add your own data members to associate extra
// information with this object. Alternatively, add this as a public base
// class to any class with a virtual destructor.
class Data {
virtual ~Data() {}
// The user data allows the clients to associate data with this object.
// Multiple user data values can be stored under different keys.
// This object will TAKE OWNERSHIP of the given data pointer, and will
// delete the object if it is changed or the object is destroyed.
Data* GetUserData(const void* key) const;
void SetUserData(const void* key, Data* data);
void RemoveUserData(const void* key);
// SupportsUserData is not thread-safe, and on debug build will assert it is
// only used on one thread. Calling this method allows the caller to hand
// the SupportsUserData instance across threads. Use only if you are taking
// full control of the synchronization of that handover.
void DetachUserDataThread();
virtual ~SupportsUserData();
// Owned by this object and scoped to its lifetime.
SupportsUserDataInternal* internal_helper_;
} // namespace ios