Experimental closure-based contexts

examples/fork.php

@@ -1,52 +1,24 @@
 <?php
-require dirname(__DIR__).'/vendor/autoload.php';
+require dirname(__DIR__) . '/vendor/autoload.php';
 
 use Icicle\Concurrent\Forking\ForkContext;
 use Icicle\Coroutine\Coroutine;
 use Icicle\Loop;
 
-class Test extends ForkContext
-{
-    /**
-     * @synchronized
-     */
-    public $data;
-
-    public function run()
-    {
+$generator = function () {
+    $context = new ForkContext(function () {
         print "Child sleeping for 4 seconds...\n";
         sleep(4);
 
-        yield $this->synchronized(function () {
-            $this->data = 'progress';
-        });
-
         print "Child sleeping for 2 seconds...\n";
         sleep(2);
-    }
-}
-
-$generator = function () {
-    $context = new Test();
-    $context->data = 'blank';
+    });
     $context->start();
 
-    Loop\timer(1, function () use ($context) {
-        $context->synchronized(function ($context) {
-            print "Finally got lock from child!\n";
-        });
-    });
-
     $timer = Loop\periodic(1, function () use ($context) {
         static $i;
         $i = $i + 1 ?: 1;
         print "Demonstrating how alive the parent is for the {$i}th time.\n";
-
-        if ($context->isRunning()) {
-            $context->synchronized(function ($context) {
-                printf("Context data: '%s'\n", $context->data);
-            });
-        }
     });
 
     try {
@@ -54,7 +26,7 @@ $generator = function () {
         print "Context done!\n";
     } catch (Exception $e) {
         print "Error from child!\n";
-        print $e."\n";
+        print $e . "\n";
     } finally {
         $timer->stop();
     }

examples/thread.php

@@ -1,25 +1,23 @@
 <?php
-require dirname(__DIR__).'/vendor/autoload.php';
+require dirname(__DIR__) . '/vendor/autoload.php';
 
 use Icicle\Concurrent\Threading\ThreadContext;
 use Icicle\Loop;
 
-class Test extends ThreadContext
-{
-    public function run()
-    {
-        print "Sleeping for 5 seconds...\n";
-        sleep(5);
-    }
-}
-
+// Create a periodic message in the main thread.
 $timer = Loop\periodic(1, function () {
     print "Demonstrating how alive the parent is.\n";
 });
 
-$test = new Test();
+// Create a new child thread that does some blocking stuff.
+$test = new ThreadContext(function () {
+    print "Sleeping for 5 seconds...\n";
+    sleep(5);
+});
+
+// Run the thread and wait asynchronously for it to finish.
 $test->start();
-$test->join()->then(function () {
+$test->join()->then(function () use ($test) {
     print "Thread ended!\n";
     Loop\stop();
 });

src/ContextInterface.php

@@ -6,6 +6,13 @@ namespace Icicle\Concurrent;
  */
 interface ContextInterface extends SynchronizableInterface
 {
+    /**
+     * Creates a new context with a given function to run.
+     *
+     * @return ContextInterface A context instance.
+     */
+    //public static function create(callable $function);
+
     /**
      * Checks if the context is running.
      *
@@ -35,9 +42,4 @@ interface ContextInterface extends SynchronizableInterface
      * @return \Icicle\Promise\PromiseInterface Promise that is resolved when the context finishes.
      */
     public function join();
-
-    /**
-     * Executes the context's main code.
-     */
-    public function run();
 }

src/Forking/ForkContext.php

@@ -11,7 +11,7 @@ use Icicle\Socket\Stream\DuplexStream;
 /**
  * Implements a UNIX-compatible context using forked processes.
  */
-abstract class ForkContext extends Synchronized implements ContextInterface
+class ForkContext extends Synchronized implements ContextInterface
 {
     const MSG_DONE = 1;
     const MSG_ERROR = 2;
@@ -21,14 +21,19 @@ abstract class ForkContext extends Synchronized implements ContextInterface
     private $pid = 0;
     private $isChild = false;
     private $deferred;
+    private $function;
 
     /**
      * Creates a new fork context.
+     *
+     * @param callable $function The function to run in the context.
      */
-    public function __construct()
+    public function __construct(callable $function)
     {
         parent::__construct();
 
+        $this->function = $function;
+
         $this->deferred = new Deferred(function (\Exception $exception) {
             $this->stop();
         });
@@ -120,22 +125,7 @@ abstract class ForkContext extends Synchronized implements ContextInterface
         Loop\clear();
 
         // Execute the context runnable and send the parent context the result.
-        try {
-            $generator = $this->run();
-            if ($generator instanceof \Generator) {
-                $coroutine = new Coroutine($generator);
-            }
-            Loop\run();
-            fwrite($this->childSocket, chr(self::MSG_DONE));
-        } catch (\Exception $exception) {
-            fwrite($this->childSocket, chr(self::MSG_ERROR));
-            $serialized = serialize($exception);
-            $length = strlen($serialized);
-            fwrite($this->childSocket, pack('S', $length).$serialized);
-        } finally {
-            fclose($this->childSocket);
-            exit(0);
-        }
+        $this->run();
     }
 
     public function stop()
@@ -166,11 +156,6 @@ abstract class ForkContext extends Synchronized implements ContextInterface
         return $this->deferred->getPromise();
     }
 
-    /**
-     * {@inheritdoc}
-     */
-    abstract public function run();
-
     public function __destruct()
     {
         parent::__destruct();
@@ -181,4 +166,24 @@ abstract class ForkContext extends Synchronized implements ContextInterface
             //$this->semaphore->destroy();
         }
     }
+
+    private function run()
+    {
+        try {
+            $generator = call_user_func($this->function);
+            if ($generator instanceof \Generator) {
+                $coroutine = new Coroutine($generator);
+            }
+            Loop\run();
+            fwrite($this->childSocket, chr(self::MSG_DONE));
+        } catch (\Exception $exception) {
+            fwrite($this->childSocket, chr(self::MSG_ERROR));
+            $serialized = serialize($exception);
+            $length = strlen($serialized);
+            fwrite($this->childSocket, pack('S', $length) . $serialized);
+        } finally {
+            fclose($this->childSocket);
+            exit(0);
+        }
+    }
 }

src/Threading/Thread.php

@@ -1,8 +1,11 @@
 <?php
 namespace Icicle\Concurrent\Threading;
 
+use Icicle\Coroutine\Coroutine;
+use Icicle\Loop;
+
 /**
- * A thread object that is used by ThreadContext.
+ * An internal thread that executes a given function concurrently.
  */
 class Thread extends \Thread
 {
@@ -10,11 +13,31 @@ class Thread extends \Thread
     const MSG_ERROR = 2;
 
     private $socket;
-    private $class;
 
-    public function __construct($class)
+    /**
+     * @var ThreadContext An instance of the context local to this thread.
+     */
+    public $context;
+
+    /**
+     * @var string|null Path to an autoloader to include.
+     */
+    public $autoloaderPath;
+
+    /**
+     * @var callable The function to execute in the thread.
+     */
+    private $function;
+
+    /**
+     * Creates a new thread object.
+     *
+     * @param callable $function The function to execute in the thread.
+     */
+    public function __construct(callable $function)
     {
-        $this->class = $class;
+        $this->function = $function;
+        $this->context = ThreadContext::createLocalInstance($this);
     }
 
     public function initialize($socket)
@@ -24,13 +47,29 @@ class Thread extends \Thread
 
     public function run()
     {
-        $class = $this->class;
-        $instance = $class::createThreadInstance();
-        $instance->run();
+        try {
+            if (file_exists($this->autoloaderPath)) {
+                require $this->autoloaderPath;
+            }
+
+            $generator = call_user_func($this->function);
+            if ($generator instanceof \Generator) {
+                $coroutine = new Coroutine($generator);
+            }
+
+            Loop\run();
 
             $this->sendMessage(self::MSG_DONE);
+        } catch (\Exception $exception) {
+            print $exception . PHP_EOL;
+            $this->sendMessage(self::MSG_ERROR);
+            $serialized = serialize($exception);
+            $length = strlen($serialized);
+            fwrite($this->socket, pack('S', $length) . $serialized);
+        } finally {
             fclose($this->socket);
         }
+    }
 
     private function sendMessage($message)
     {

src/Threading/ThreadContext.php

@@ -13,7 +13,7 @@ use Icicle\Socket\Stream\DuplexStream;
  * maintained both in the context that creates the thread and in the thread
  * itself.
  */
-abstract class ThreadContext implements ContextInterface
+class ThreadContext implements ContextInterface
 {
     /**
      * @var \Thread A thread instance.
@@ -30,22 +30,39 @@ abstract class ThreadContext implements ContextInterface
      */
     private $socket;
 
-    public static function createThreadInstance()
+    /**
+     * @var A reference handle to the invoker.
+     */
+    private $invoker;
+
+    /**
+     * Creates an instance of the current context class for the local thread.
+     *
+     * @return self
+     *
+     * @internal
+     */
+    final public static function createLocalInstance(Thread $thread)
     {
         $class = new \ReflectionClass(static::class);
-        return $class->newInstanceWithoutConstructor();
+        $instance = $class->newInstanceWithoutConstructor();
+        $instance->thread = $thread;
+        return $instance;
     }
 
     /**
      * Creates a new thread context.
+     *
+     * @param callable $function The function to run in the thread.
      */
-    public function __construct()
+    public function __construct(callable $function)
     {
         $this->deferredJoin = new Promise\Deferred(function () {
             $this->kill();
         });
 
-        $this->thread = new Thread(static::class);
+        $this->thread = new Thread($function);
+        $this->thread->autoloaderPath = $this->getComposerAutoloader();
     }
 
     /**
@@ -65,11 +82,8 @@ abstract class ThreadContext implements ContextInterface
             throw new \Exception();
         }
 
-        // When the thread is started, the event loop will be duplicated, so we
-        // need to start the thread before we add anything else to the event loop
-        // or we will cause a segmentation fault.
         $this->thread->initialize($sockets[1]);
-        $this->thread->start(PTHREADS_INHERIT_ALL);
+        $this->thread->start(PTHREADS_INHERIT_INI);
 
         $this->socket = new DuplexStream($sockets[0]);
 
@@ -152,4 +166,25 @@ abstract class ThreadContext implements ContextInterface
 
         return $returnValue;
     }
+
+    /**
+     * Gets the full path to the Composer autoloader.
+     *
+     * If no Composer autoloader is being used, `null` is returned.
+     *
+     * @return \Composer\Autoload\ClassLoader|null
+     */
+    private function getComposerAutoloader()
+    {
+        foreach (get_included_files() as $path) {
+            if (strpos($path, 'vendor/autoload.php') !== false) {
+                $source = file_get_contents($path);
+                if (strpos($source, '@generated by Composer') !== false) {
+                    return $path;
+                }
+            }
+        }
+
+        return null;
+    }
 }