tdesktop/Telegram/SourceFiles/base/observer.cpp

81 lines
2.2 KiB
C++

/*
This file is part of Telegram Desktop,
the official desktop version of Telegram messaging app, see https://telegram.org
Telegram Desktop is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
It is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
In addition, as a special exception, the copyright holders give permission
to link the code of portions of this program with the OpenSSL library.
Full license: https://github.com/telegramdesktop/tdesktop/blob/master/LICENSE
Copyright (c) 2014-2017 John Preston, https://desktop.telegram.org
*/
#include "base/observer.h"
namespace base {
namespace internal {
namespace {
bool CantUseObservables = false;
struct ObservableListWrap {
~ObservableListWrap() {
CantUseObservables = true;
}
OrderedSet<ObservableCallHandlers*> list;
};
ObservableListWrap &PendingObservables() {
static ObservableListWrap result;
return result;
}
ObservableListWrap &ActiveObservables() {
static ObservableListWrap result;
return result;
}
} // namespace
void RegisterPendingObservable(ObservableCallHandlers *handlers) {
if (CantUseObservables) return;
PendingObservables().list.insert(handlers);
Global::RefHandleObservables().call();
}
void UnregisterActiveObservable(ObservableCallHandlers *handlers) {
if (CantUseObservables) return;
ActiveObservables().list.remove(handlers);
}
void UnregisterObservable(ObservableCallHandlers *handlers) {
if (CantUseObservables) return;
PendingObservables().list.remove(handlers);
ActiveObservables().list.remove(handlers);
}
} // namespace internal
void HandleObservables() {
if (internal::CantUseObservables) return;
auto &active = internal::ActiveObservables().list;
qSwap(active, internal::PendingObservables().list);
while (!active.empty()) {
auto first = *active.begin();
(*first)();
if (!active.empty() && *active.begin() == first) {
active.erase(active.begin());
}
}
}
} // namespace base