LNXSDK/Kha/Tools/windows_x64/std/sys/thread/FixedThreadPool.hx
2025-01-22 16:18:30 +01:00

116 lines
3.3 KiB
Haxe

/*
* Copyright (C)2005-2019 Haxe Foundation
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*/
package sys.thread;
#if (!target.threaded)
#error "This class is not available on this target"
#end
import haxe.Exception;
/**
Thread pool with a constant amount of threads.
Threads in the pool will exist until the pool is explicitly shut down.
**/
@:coreApi
class FixedThreadPool implements IThreadPool {
/* Amount of threads in this pool. */
public var threadsCount(get,null):Int;
function get_threadsCount():Int return threadsCount;
/** Indicates if `shutdown` method of this pool has been called. */
public var isShutdown(get,never):Bool;
var _isShutdown = false;
function get_isShutdown():Bool return _isShutdown;
final pool:Array<Worker>;
final poolMutex = new Mutex();
final queue = new Deque<()->Void>();
/**
Create a new thread pool with `threadsCount` threads.
**/
public function new(threadsCount:Int):Void {
if(threadsCount < 1)
throw new ThreadPoolException('FixedThreadPool needs threadsCount to be at least 1.');
this.threadsCount = threadsCount;
pool = [for(i in 0...threadsCount) new Worker(queue)];
}
/**
Submit a task to run in a thread.
Throws an exception if the pool is shut down.
**/
public function run(task:()->Void):Void {
if(_isShutdown)
throw new ThreadPoolException('Task is rejected. Thread pool is shut down.');
if(task == null)
throw new ThreadPoolException('Task to run must not be null.');
queue.add(task);
}
/**
Initiates a shutdown.
All previousely submitted tasks will be executed, but no new tasks will
be accepted.
Multiple calls to this method have no effect.
**/
public function shutdown():Void {
if(_isShutdown) return;
_isShutdown = true;
for(_ in pool) {
queue.add(shutdownTask);
}
}
static function shutdownTask():Void {
throw new ShutdownException('');
}
}
private class ShutdownException extends Exception {}
private class Worker {
var thread:Thread;
final queue:Deque<Null<()->Void>>;
public function new(queue:Deque<Null<()->Void>>) {
this.queue = queue;
thread = Thread.create(loop);
}
function loop() {
try {
while(true) {
var task = queue.pop(true);
task();
}
} catch(_:ShutdownException) {
} catch(e) {
thread = Thread.create(loop);
throw e;
}
}
}