PHP底層的執行緒池與協程實作方法

class ThreadPool
{
    private $pool;
    private $maxThreads;

    public function __construct($maxThreads)
    {
        $this->maxThreads = $maxThreads;
        $this->pool = new SplQueue();
    }

    public function run($task)
    {
        if(count($this->pool) < $this->maxThreads) {
            $thread = new Thread($task);
            $thread->start();
            $this->pool->enqueue($thread);
        } else {
            while(count($this->pool) >= $this->maxThreads) {
                usleep(1000);
            }
            $this->run($task); // 递归调用，直到有空闲线程
        }
    }

    public function wait()
    {
        while(!$this->pool->isEmpty()) {
            $thread = $this->pool->dequeue();
            $thread->join();
        }
    }
}

class Thread extends Thread {
    private $task;

    public function __construct($task) {
        $this->task = $task;
    }

    public function run() {
        // 执行任务
        call_user_func($this->task);
    }
}

// 示例
$pool = new ThreadPool(5);
for($i = 0; $i < 10; $i++) {
    $task = function() use($i) {
        echo "Task " . $i . " is running in thread " . Thread::getCurrentThreadId() . "
";
        usleep(1000000);
        echo "Task " . $i . " is completed
";
    };
    $pool->run($task);
}
$pool->wait();

function coroutine() {
    $task = (yield); // 获取第一个任务
    while($task) {
        call_user_func($task);
        $task = (yield); // 获取下一个任务
    }
}

// 示例
$coroutine = coroutine();
$coroutine->send(function() {
    echo "Task 1 is running
";
    usleep(1000000);
    echo "Task 1 is completed
";
});
$coroutine->send(function() {
    echo "Task 2 is running
";
    usleep(1000000);
    echo "Task 2 is completed
";
});