AsyncTask: partial backport of 6ac0c517f54dc83fc23f41a6797c14e1f4b457a1 (simplify TLS)

- deprecated AsyncTask::peekLocal()
- AsyncTask::fetchLocal() no longer deletes stored data
This commit is contained in:
Dylan K. Taylor 2019-07-27 15:09:42 +01:00
parent 87fb42cabd
commit cde2c10c1d

View File

@ -51,7 +51,7 @@ abstract class AsyncTask extends Collectable{
* @var \SplObjectStorage|null * @var \SplObjectStorage|null
* Used to store objects on the main thread which should not be serialized. * Used to store objects on the main thread which should not be serialized.
*/ */
private static $localObjectStorage; private static $threadLocalStorage;
/** @var AsyncWorker $worker */ /** @var AsyncWorker $worker */
public $worker = null; public $worker = null;
@ -229,9 +229,6 @@ abstract class AsyncTask extends Collectable{
* *
* Scalar types can be stored directly in class properties instead of using this storage. * Scalar types can be stored directly in class properties instead of using this storage.
* *
* Objects stored in this storage MUST be retrieved through {@link AsyncTask::fetchLocal} when {@link AsyncTask::onCompletion} is called.
* Otherwise, a NOTICE level message will be raised and the reference will be removed after onCompletion exits.
*
* WARNING: THIS METHOD SHOULD ONLY BE CALLED FROM THE MAIN THREAD! * WARNING: THIS METHOD SHOULD ONLY BE CALLED FROM THE MAIN THREAD!
* *
* @param mixed $complexData the data to store * @param mixed $complexData the data to store
@ -243,26 +240,19 @@ abstract class AsyncTask extends Collectable{
throw new \BadMethodCallException("Objects can only be stored from the parent thread"); throw new \BadMethodCallException("Objects can only be stored from the parent thread");
} }
if(self::$localObjectStorage === null){ if(self::$threadLocalStorage === null){
self::$localObjectStorage = new \SplObjectStorage(); //lazy init self::$threadLocalStorage = new \SplObjectStorage(); //lazy init
} }
if(isset(self::$localObjectStorage[$this])){ if(isset(self::$threadLocalStorage[$this])){
throw new \InvalidStateException("Already storing complex data for this async task"); throw new \InvalidStateException("Already storing complex data for this async task");
} }
self::$localObjectStorage[$this] = $complexData; self::$threadLocalStorage[$this] = $complexData;
} }
/** /**
* Returns and removes mixed data in thread-local storage on the parent thread. Call this method from * Returns data previously stored in thread-local storage on the parent thread. Use this during progress updates or
* {@link AsyncTask::onCompletion} to fetch the data stored in the object store, if any. * task completion to retrieve data you stored using {@link AsyncTask::storeLocal}.
*
* If no data was stored in the local store, or if the data was already retrieved by a previous call to fetchLocal,
* do NOT call this method, or an exception will be thrown.
*
* Do not call this method from {@link AsyncTask::onProgressUpdate}, because this method deletes stored data, which
* means that you will not be able to retrieve it again afterwards. Use {@link AsyncTask::peekLocal} instead to
* retrieve stored data without removing it from the store.
* *
* WARNING: THIS METHOD SHOULD ONLY BE CALLED FROM THE MAIN THREAD! * WARNING: THIS METHOD SHOULD ONLY BE CALLED FROM THE MAIN THREAD!
* *
@ -272,25 +262,20 @@ abstract class AsyncTask extends Collectable{
* @throws \BadMethodCallException if called from any thread except the main thread * @throws \BadMethodCallException if called from any thread except the main thread
*/ */
protected function fetchLocal(){ protected function fetchLocal(){
try{ if($this->worker !== null and $this->worker === \Thread::getCurrentThread()){
return $this->peekLocal(); throw new \BadMethodCallException("Objects can only be retrieved from the parent thread");
}finally{
if(self::$localObjectStorage !== null){
unset(self::$localObjectStorage[$this]);
}
} }
if(self::$threadLocalStorage === null or !isset(self::$threadLocalStorage[$this])){
throw new \InvalidStateException("No complex data stored for this async task");
}
return self::$threadLocalStorage[$this];
} }
/** /**
* Returns mixed data in thread-local storage on the parent thread **without clearing** it. Call this method from * @deprecated
* {@link AsyncTask::onProgressUpdate} to fetch the data stored if you need to be able to access the data later on, * @see AsyncTask::fetchLocal()
* such as in another progress update.
*
* Use {@link AsyncTask::fetchLocal} instead from {@link AsyncTask::onCompletion}, because this method does not delete
* the data, and not clearing the data will result in a warning for memory leak after {@link AsyncTask::onCompletion}
* finished executing.
*
* WARNING: THIS METHOD SHOULD ONLY BE CALLED FROM THE MAIN THREAD!
* *
* @return mixed * @return mixed
* *
@ -298,27 +283,15 @@ abstract class AsyncTask extends Collectable{
* @throws \BadMethodCallException if called from any thread except the main thread * @throws \BadMethodCallException if called from any thread except the main thread
*/ */
protected function peekLocal(){ protected function peekLocal(){
if($this->worker !== null and $this->worker === \Thread::getCurrentThread()){ return $this->fetchLocal();
throw new \BadMethodCallException("Objects can only be retrieved from the parent thread");
}
if(self::$localObjectStorage === null or !isset(self::$localObjectStorage[$this])){
throw new \InvalidStateException("No complex data stored for this async task");
}
return self::$localObjectStorage[$this];
} }
/** /**
* @internal Called by the AsyncPool to destroy any leftover stored objects that this task failed to retrieve. * @internal Called by the AsyncPool to destroy any leftover stored objects that this task failed to retrieve.
* @return bool
*/ */
public function removeDanglingStoredObjects() : bool{ public function removeDanglingStoredObjects() : void{
if(self::$localObjectStorage !== null and isset(self::$localObjectStorage[$this])){ if(self::$threadLocalStorage !== null and isset(self::$threadLocalStorage[$this])){
unset(self::$localObjectStorage[$this]); unset(self::$threadLocalStorage[$this]);
return true;
} }
return false;
} }
} }