mirror of https://github.com/dcoredump/dexed.git
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
86 lines
2.8 KiB
86 lines
2.8 KiB
/*
|
|
==============================================================================
|
|
|
|
This file is part of the JUCE library.
|
|
Copyright (c) 2015 - ROLI Ltd.
|
|
|
|
Permission is granted to use this software under the terms of either:
|
|
a) the GPL v2 (or any later version)
|
|
b) the Affero GPL v3
|
|
|
|
Details of these licenses can be found at: www.gnu.org/licenses
|
|
|
|
JUCE 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.
|
|
|
|
------------------------------------------------------------------------------
|
|
|
|
To release a closed-source product which uses JUCE, commercial licenses are
|
|
available: visit www.juce.com for more information.
|
|
|
|
==============================================================================
|
|
*/
|
|
|
|
class AsyncUpdater::AsyncUpdaterMessage : public CallbackMessage
|
|
{
|
|
public:
|
|
AsyncUpdaterMessage (AsyncUpdater& au) : owner (au) {}
|
|
|
|
void messageCallback() override
|
|
{
|
|
if (shouldDeliver.compareAndSetBool (0, 1))
|
|
owner.handleAsyncUpdate();
|
|
}
|
|
|
|
Atomic<int> shouldDeliver;
|
|
|
|
private:
|
|
AsyncUpdater& owner;
|
|
|
|
JUCE_DECLARE_NON_COPYABLE (AsyncUpdaterMessage)
|
|
};
|
|
|
|
//==============================================================================
|
|
AsyncUpdater::AsyncUpdater()
|
|
{
|
|
activeMessage = new AsyncUpdaterMessage (*this);
|
|
}
|
|
|
|
AsyncUpdater::~AsyncUpdater()
|
|
{
|
|
// You're deleting this object with a background thread while there's an update
|
|
// pending on the main event thread - that's pretty dodgy threading, as the callback could
|
|
// happen after this destructor has finished. You should either use a MessageManagerLock while
|
|
// deleting this object, or find some other way to avoid such a race condition.
|
|
jassert ((! isUpdatePending()) || MessageManager::getInstance()->currentThreadHasLockedMessageManager());
|
|
|
|
activeMessage->shouldDeliver.set (0);
|
|
}
|
|
|
|
void AsyncUpdater::triggerAsyncUpdate()
|
|
{
|
|
if (activeMessage->shouldDeliver.compareAndSetBool (1, 0))
|
|
if (! activeMessage->post())
|
|
cancelPendingUpdate(); // if the message queue fails, this avoids getting
|
|
// trapped waiting for the message to arrive
|
|
}
|
|
|
|
void AsyncUpdater::cancelPendingUpdate() noexcept
|
|
{
|
|
activeMessage->shouldDeliver.set (0);
|
|
}
|
|
|
|
void AsyncUpdater::handleUpdateNowIfNeeded()
|
|
{
|
|
// This can only be called by the event thread.
|
|
jassert (MessageManager::getInstance()->currentThreadHasLockedMessageManager());
|
|
|
|
if (activeMessage->shouldDeliver.exchange (0) != 0)
|
|
handleAsyncUpdate();
|
|
}
|
|
|
|
bool AsyncUpdater::isUpdatePending() const noexcept
|
|
{
|
|
return activeMessage->shouldDeliver.value != 0;
|
|
}
|
|
|