Nagram/TMessagesProj/jni/webrtc/base/supports_user_data.cc
2020-08-14 19:58:22 +03:00

75 lines
2.3 KiB
C++

// Copyright (c) 2012 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 "base/supports_user_data.h"
namespace base {
std::unique_ptr<SupportsUserData::Data> SupportsUserData::Data::Clone() {
return nullptr;
}
SupportsUserData::SupportsUserData() {
// Harmless to construct on a different execution sequence to subsequent
// usage.
sequence_checker_.DetachFromSequence();
}
SupportsUserData::SupportsUserData(SupportsUserData&&) = default;
SupportsUserData& SupportsUserData::operator=(SupportsUserData&&) = default;
SupportsUserData::Data* SupportsUserData::GetUserData(const void* key) const {
DCHECK(sequence_checker_.CalledOnValidSequence());
// Avoid null keys; they are too vulnerable to collision.
DCHECK(key);
auto found = user_data_.find(key);
if (found != user_data_.end())
return found->second.get();
return nullptr;
}
void SupportsUserData::SetUserData(const void* key,
std::unique_ptr<Data> data) {
DCHECK(sequence_checker_.CalledOnValidSequence());
// Avoid null keys; they are too vulnerable to collision.
DCHECK(key);
if (data.get())
user_data_[key] = std::move(data);
else
RemoveUserData(key);
}
void SupportsUserData::RemoveUserData(const void* key) {
DCHECK(sequence_checker_.CalledOnValidSequence());
user_data_.erase(key);
}
void SupportsUserData::DetachFromSequence() {
sequence_checker_.DetachFromSequence();
}
void SupportsUserData::CloneDataFrom(const SupportsUserData& other) {
for (const auto& data_pair : other.user_data_) {
auto cloned_data = data_pair.second->Clone();
if (cloned_data)
SetUserData(data_pair.first, std::move(cloned_data));
}
}
SupportsUserData::~SupportsUserData() {
DCHECK(sequence_checker_.CalledOnValidSequence() || user_data_.empty());
DataMap local_user_data;
user_data_.swap(local_user_data);
// Now this->user_data_ is empty, and any destructors called transitively from
// the destruction of |local_user_data| will see it that way instead of
// examining a being-destroyed object.
}
void SupportsUserData::ClearAllUserData() {
DCHECK(sequence_checker_.CalledOnValidSequence());
user_data_.clear();
}
} // namespace base