Remove dependency on amphp/socket

bin/worker

@@ -2,9 +2,8 @@
 <?php declare(strict_types = 1);
 
 use Amp\Parallel\{ ChannelException, SerializationException} ;
-use Amp\Parallel\Sync\{ ChannelledStream, Internal\ExitFailure, Internal\ExitSuccess };
+use Amp\Parallel\Sync\{ ChannelledSocket, Internal\ExitFailure, Internal\ExitSuccess };
 use Amp\Parallel\Worker\{ BasicEnvironment, Internal\TaskRunner };
-use Amp\Socket\Socket;
 
 @cli_set_process_title("amp-worker");
 error_reporting(E_ALL);
@@ -38,7 +37,7 @@ ob_start(function ($data) {
 })();
 
 Amp\execute(function () {
-    $channel = new ChannelledStream(new Socket(STDIN, false), new Socket(STDOUT, false));
+    $channel = new ChannelledSocket(STDIN, STDOUT, false);
     $environment = new BasicEnvironment;
     $runner = new TaskRunner($channel, $environment);
 

composer.json

@@ -21,11 +21,11 @@
         }
     ],
     "require": {
-        "amphp/amp": "^2.0",
+        "amphp/amp": "^2.0"
-        "amphp/socket": "dev-amp_v2 as 0.2"
     },
     "require-dev": {
         "amphp/loop": "dev-master",
+        "amphp/stream": "dev-master as 0.1",
         "phpunit/phpunit": "^5.0"
     },
     "minimum-stability": "dev",

lib/Forking/Fork.php

@@ -12,21 +12,17 @@ use Amp\Parallel\{
     Strand,
     SynchronizationError
 };
-use Amp\Parallel\Sync\{ Channel, ChannelledStream };
+use Amp\Parallel\Sync\{ Channel, ChannelledSocket };
 use Amp\Parallel\Sync\Internal\{ ExitFailure, ExitStatus, ExitSuccess };
-use Amp\Socket\Socket;
 use Interop\Async\Awaitable;
 
 /**
  * Implements a UNIX-compatible context using forked processes.
  */
 class Fork implements Process, Strand {
-    /** @var \Amp\Parallel\Sync\Channel A channel for communicating with the child. */
+    /** @var \Amp\Parallel\Sync\ChannelledSocket A channel for communicating with the child. */
     private $channel;
 
-    /** @var \Amp\Socket\Socket */
-    private $pipe;
-
     /** @var int */
     private $pid = 0;
 
@@ -73,7 +69,6 @@ class Fork implements Process, Strand {
     public function __clone() {
         $this->pid = 0;
         $this->oid = 0;
-        $this->pipe = null;
         $this->channel = null;
     }
 
@@ -152,14 +147,23 @@ class Fork implements Process, Strand {
      * Starts the context execution.
      *
      * @throws \Amp\Parallel\ContextException If forking fails.
-     * @throws \Amp\Socket\SocketException If creating a socket pair fails.
      */
     public function start() {
         if (0 !== $this->oid) {
             throw new StatusError('The context has already been started.');
         }
 
-        list($parent, $child) = \Amp\Socket\pair();
+        $sockets = @\stream_socket_pair(STREAM_PF_UNIX, STREAM_SOCK_STREAM, STREAM_IPPROTO_IP);
+
+        if ($sockets === false) {
+                $message = "Failed to create socket pair";
+                if ($error = \error_get_last()) {
+                    $message .= \sprintf(" Errno: %d; %s", $error["type"], $error["message"]);
+                }
+                throw new ContextException($message);
+        }
+
+        list($parent, $child) = $sockets;
 
         switch ($pid = \pcntl_fork()) {
             case -1: // Failure
@@ -171,7 +175,7 @@ class Fork implements Process, Strand {
 
                 try {
                     \Amp\execute(function () use ($parent) {
-                        $channel = new ChannelledStream(new Socket($parent));
+                        $channel = new ChannelledSocket($parent, $parent);
                         return $this->execute($channel);
                     });
                     $code = 0;
@@ -184,7 +188,7 @@ class Fork implements Process, Strand {
             default: // Parent
                 $this->pid = $pid;
                 $this->oid = \posix_getpid();
-                $this->channel = new ChannelledStream($this->pipe = new Socket($child));
+                $this->channel = new ChannelledSocket($child, $child);
                 \fclose($parent);
         }
     }
@@ -248,8 +252,8 @@ class Fork implements Process, Strand {
             \posix_kill($this->pid, SIGKILL);
         }
 
-        if (null !== $this->pipe && $this->pipe->isReadable()) {
+        if ($this->channel !== null) {
-            $this->pipe->close();
+            $this->channel->close();
         }
 
         // "Detach" from the process and let it die asynchronously.

lib/Process/ChannelledProcess.php

@@ -3,7 +3,7 @@
 namespace Amp\Parallel\Process;
 
 use Amp\Parallel\{ Process as ProcessContext, StatusError, Strand, SynchronizationError };
-use Amp\Parallel\Sync\{ ChannelledStream, Internal\ExitStatus };
+use Amp\Parallel\Sync\{ ChannelledSocket, Internal\ExitStatus };
 use Interop\Async\Awaitable;
 
 class ChannelledProcess implements ProcessContext, Strand {
@@ -36,7 +36,7 @@ class ChannelledProcess implements ProcessContext, Strand {
      */
     public function start() {
         $this->process->start();
-        $this->channel = new ChannelledStream($this->process->getStdOut(), $this->process->getStdIn());
+        $this->channel = new ChannelledSocket($this->process->getStdOut(), $this->process->getStdIn(), false);
     }
 
     /**

lib/Process/Process.php

@@ -4,8 +4,6 @@ namespace Amp\Parallel\Process;
 
 use Amp\Deferred;
 use Amp\Parallel\{ ContextException, Process as ProcessContext, StatusError };
-use Amp\Socket\Socket;
-use Amp\Stream\Stream;
 use Interop\Async\{ Awaitable, Loop };
 
 class Process implements ProcessContext {
@@ -24,13 +22,13 @@ class Process implements ProcessContext {
     /** @var array */
     private $options;
     
-    /** @var \Amp\Stream\Stream|null */
+    /** @var resource|null */
     private $stdin;
 
-    /** @var \Amp\Stream\Stream|null */
+    /** @var resource|null */
     private $stdout;
 
-    /** @var \Amp\Stream\Stream|null */
+    /** @var resource|null */
     private $stderr;
 
     /** @var int */
@@ -75,16 +73,16 @@ class Process implements ProcessContext {
         if (\getmypid() === $this->oid) {
             $this->kill(); // Will only terminate if the process is still running.
     
-            if ($this->stdin !== null) {
+            if (\is_resource($this->stdin)) {
-                $this->stdin->close();
+                \fclose($this->stdin);
             }
     
-            if ($this->stdout !== null) {
+            if (\is_resource($this->stdout)) {
-                $this->stdout->close();
+                \fclose($this->stdout);
             }
     
-            if ($this->stderr !== null) {
+            if (\is_resource($this->stderr)) {
-                $this->stderr->close();
+                \fclose($this->stderr);
             }
         }
     }
@@ -146,9 +144,9 @@ class Process implements ProcessContext {
 
         $this->pid = $status["pid"];
 
-        $this->stdin = $stdin = new Socket($pipes[0]);
+        $this->stdin = $stdin = $pipes[0];
-        $this->stdout = new Socket($pipes[1]);
+        $this->stdout = $pipes[1];
-        $this->stderr = new Socket($pipes[2]);
+        $this->stderr = $pipes[2];
 
         $stream = $pipes[3];
         \stream_set_blocking($stream, false);
@@ -175,7 +173,9 @@ class Process implements ProcessContext {
                         \proc_close($process);
                         $process = null;
                     }
-                    $stdin->close();
+                    if (\is_resource($stdin)) {
+                        \fclose($stdin);
+                    }
                     Loop::cancel($watcher);
                 }
                 
@@ -200,14 +200,10 @@ class Process implements ProcessContext {
 
         Loop::enable($this->watcher);
 
-        $awaitable = $this->deferred->getAwaitable();
+        \fclose($this->stdout);
+        \fclose($this->stderr);
 
-        $awaitable->when(function () {
+        return $this->deferred->getAwaitable();
-            $this->stdout->close();
-            $this->stderr->close();
-        });
-        
-        return $awaitable;
     }
 
     /**
@@ -304,11 +300,11 @@ class Process implements ProcessContext {
     /**
      * Gets the process input stream (STDIN).
      *
-     * @return \Amp\Stream\Stream
+     * @return resource
      *
      * @throws \Amp\Parallel\StatusError If the process is not running.
      */
-    public function getStdIn(): Stream {
+    public function getStdIn() {
         if ($this->stdin === null) {
             throw new StatusError("The process has not been started");
         }
@@ -319,11 +315,11 @@ class Process implements ProcessContext {
     /**
      * Gets the process output stream (STDOUT).
      *
-     * @return \Amp\Stream\Stream
+     * @return resource
      *
      * @throws \Amp\Parallel\StatusError If the process is not running.
      */
-    public function getStdOut(): Stream {
+    public function getStdOut() {
         if ($this->stdout === null) {
             throw new StatusError("The process has not been started");
         }
@@ -334,11 +330,11 @@ class Process implements ProcessContext {
     /**
      * Gets the process error stream (STDERR).
      *
-     * @return \Amp\Stream\Stream
+     * @return resource
      *
      * @throws \Amp\Parallel\StatusError If the process is not running.
      */
-    public function getStdErr(): Stream {
+    public function getStdErr() {
         if ($this->stderr === null) {
             throw new StatusError("The process has not been started");
         }

lib/Sync/ChannelledSocket.php

@@ -0,0 +1,309 @@
+<?php declare(strict_types = 1);
+
+namespace Amp\Parallel\Sync;
+
+use Amp\{ Coroutine, Deferred, Failure, Success };
+use Amp\Parallel\{ ChannelException, SerializationException };
+use Interop\Async\{ Awaitable, Loop };
+
+class ChannelledSocket implements Channel {
+    const HEADER_LENGTH = 5;
+    
+    /** @var resource Stream resource. */
+    private $readResource;
+    
+    /** @var resource Stream resource. */
+    private $writeResource;
+    
+    /** @var string onReadable loop watcher. */
+    private $readWatcher;
+    
+    /** @var string onWritable loop watcher. */
+    private $writeWatcher;
+    
+    /** @var \SplQueue Queue of pending reads. */
+    private $reads;
+    
+    /** @var \SplQueue Queue of pending writes. */
+    private $writes;
+    
+    /** @var bool */
+    private $open = true;
+    
+    /** @var bool */
+    private $autoClose = true;
+    
+    /**
+     * @param resource $resource Stream resource.
+     * @param bool $autoClose True to close the stream resource when this object is destroyed, false to leave open.
+     *
+     * @throws \Error If a stream resource is not given for $resource.
+     */
+    public function __construct($read, $write, bool $autoClose = true) {
+        if (!\is_resource($read) ||\get_resource_type($read) !== 'stream') {
+            throw new \Error('Invalid resource given to constructor!');
+        }
+    
+        if (!\is_resource($write) ||\get_resource_type($write) !== 'stream') {
+            throw new \Error('Invalid resource given to constructor!');
+        }
+        
+        $this->readResource = $read;
+        $this->writeResource = $write;
+        $this->autoClose = $autoClose;
+        
+        \stream_set_blocking($this->readResource, false);
+        \stream_set_read_buffer($this->readResource, 0);
+        \stream_set_write_buffer($this->readResource, 0);
+        
+        if ($this->readResource !== $this->writeResource) {
+            \stream_set_blocking($this->writeResource, false);
+            \stream_set_read_buffer($this->writeResource, 0);
+            \stream_set_write_buffer($this->writeResource, 0);
+        }
+        
+        $this->reads = $reads = new \SplQueue;
+        $this->writes = $writes = new \SplQueue;
+    
+        $errorHandler = static function ($errno, $errstr) {
+            throw new ChannelException(\sprintf('Received corrupted data. Errno: %d; %s', $errno, $errstr));
+        };
+        
+        $this->readWatcher = Loop::onReadable($this->readResource, static function ($watcher, $stream) use ($reads, $errorHandler) {
+            while (!$reads->isEmpty()) {
+                /** @var \Amp\Deferred $deferred */
+                list($buffer, $length, $deferred) = $reads->shift();
+                
+                if ($length === 0) {
+                    // Error reporting suppressed since fread() produces a warning if the stream unexpectedly closes.
+                    $data = @\fread($stream, self::HEADER_LENGTH - \strlen($buffer));
+                    
+                    if ($data === false || ($data === '' && (\feof($stream) || !\is_resource($stream)))) {
+                        $deferred->fail(new ChannelException("The socket unexpectedly closed"));
+                        return;
+                    }
+                    
+                    $buffer .= $data;
+                    
+                    if (\strlen($buffer) !== self::HEADER_LENGTH) {
+                        // Not enough data available.
+                        $reads->unshift([$buffer, 0, $deferred]);
+                        return;
+                    }
+    
+                    $data = \unpack("Cprefix/Llength", $data);
+    
+                    if ($data["prefix"] !== 0) {
+                        $deferred->fail(new ChannelException("Invalid header received"));
+                        return;
+                    }
+                    
+                    $length = $data["length"];
+                    $buffer = '';
+                }
+    
+                // Error reporting suppressed since fread() produces a warning if the stream unexpectedly closes.
+                $data = @\fread($stream, $length - \strlen($buffer));
+    
+                if ($data === false || ($data === '' && (\feof($stream) || !\is_resource($stream)))) {
+                    $deferred->fail(new ChannelException("The socket unexpectedly closed"));
+                    return;
+                }
+                
+                $buffer .= $data;
+                
+                if (\strlen($buffer) < $length) {
+                    // Not enough data available.
+                    $reads->unshift([$buffer, $length, $deferred]);
+                    return;
+                }
+    
+                \set_error_handler($errorHandler);
+    
+                // Attempt to unserialize the received data.
+                try {
+                    $data = \unserialize($buffer);
+                } catch (\Throwable $exception) {
+                    $deferred->fail(new SerializationException("Exception thrown when unserializing data", $exception));
+                    continue;
+                } finally {
+                    \restore_error_handler();
+                }
+    
+                $deferred->resolve($data);
+            }
+            
+            Loop::disable($watcher);
+        });
+        
+        $this->writeWatcher = Loop::onWritable($this->writeResource, static function ($watcher, $stream) use ($writes) {
+            while (!$writes->isEmpty()) {
+                /** @var \Amp\Deferred $deferred */
+                list($data, $previous, $deferred) = $writes->shift();
+                $length = \strlen($data);
+                
+                if ($length === 0) {
+                    $deferred->resolve(0);
+                    continue;
+                }
+                
+                // Error reporting suppressed since fwrite() emits E_WARNING if the pipe is broken or the buffer is full.
+                $written = @\fwrite($stream, $data);
+                
+                if ($written === false || $written === 0) {
+                    $message = "Failed to write to socket";
+                    if ($error = \error_get_last()) {
+                        $message .= \sprintf(" Errno: %d; %s", $error["type"], $error["message"]);
+                    }
+                    $deferred->fail(new ChannelException($message));
+                    return;
+                }
+                
+                if ($length <= $written) {
+                    $deferred->resolve($written + $previous);
+                    continue;
+                }
+                
+                $data = \substr($data, $written);
+                $writes->unshift([$data, $written + $previous, $deferred]);
+                return;
+            }
+        });
+        
+        Loop::disable($this->readWatcher);
+        Loop::disable($this->writeWatcher);
+    }
+    
+    public function __destruct() {
+        if ($this->readResource !== null) {
+            $this->close();
+        }
+    }
+    
+    /**
+     * {@inheritdoc}
+     */
+    public function close() {
+        if (\is_resource($this->readResource)) {
+            if ($this->autoClose) {
+                @\fclose($this->readResource);
+                
+                if ($this->readResource !== $this->writeResource) {
+                    @\fclose($this->writeResource);
+                }
+            }
+            $this->readResource = null;
+            $this->writeResource = null;
+        }
+        
+        $this->open = false;
+        
+        if (!$this->reads->isEmpty()) {
+            $exception = new ChannelException("The connection was unexpectedly closed before reading completed");
+            do {
+                /** @var \Amp\Deferred $deferred */
+                list( , , $deferred) = $this->reads->shift();
+                $deferred->fail($exception);
+            } while (!$this->reads->isEmpty());
+        }
+        
+        if (!$this->writes->isEmpty()) {
+            $exception = new ChannelException("The connection was unexpectedly writing completed");
+            do {
+                /** @var \Amp\Deferred $deferred */
+                list( , , $deferred) = $this->writes->shift();
+                $deferred->fail($exception);
+            } while (!$this->writes->isEmpty());
+        }
+        
+        // defer this, else the Loop::disable() may be invalid
+        $read = $this->readWatcher;
+        $write = $this->writeWatcher;
+        Loop::defer(static function () use ($read, $write) {
+            Loop::cancel($read);
+            Loop::cancel($write);
+        });
+    }
+    
+    /**
+     * {@inheritdoc}
+     */
+    public function receive(): Awaitable {
+        if (!$this->open) {
+            return new Failure(new ChannelException("The channel is has been closed"));
+        }
+        
+        $deferred = new Deferred;
+        $this->reads->push(["", 0, $deferred]);
+        
+        Loop::enable($this->readWatcher);
+        
+        return $deferred->getAwaitable();
+    }
+    
+    /**
+     * @param string $data
+     * @param bool $end
+     *
+     * @return \Interop\Async\Awaitable
+     */
+    public function send($data): Awaitable {
+        if (!$this->open) {
+            return new Failure(new ChannelException("The channel is has been closed"));
+        }
+    
+        // Serialize the data to send into the channel.
+        try {
+            $data = \serialize($data);
+        } catch (\Throwable $exception) {
+            throw new SerializationException(
+                "The given data cannot be sent because it is not serializable.", $exception
+            );
+        }
+        
+        $length = \strlen($data);
+        $data = \pack("CL", 0, $length) . $data;
+        $written = 0;
+        
+        if ($this->writes->isEmpty()) {
+            // Error reporting suppressed since fwrite() emits E_WARNING if the pipe is broken or the buffer is full.
+            $written = @\fwrite($this->writeResource, $data);
+            
+            if ($written === false) {
+                $message = "Failed to write to stream";
+                if ($error = \error_get_last()) {
+                    $message .= \sprintf(" Errno: %d; %s", $error["type"], $error["message"]);
+                }
+                return new Failure(new ChannelException($message));
+            }
+            
+            if ($length <= $written) {
+                return new Success($written);
+            }
+            
+            $data = \substr($data, $written);
+        }
+        
+        return new Coroutine($this->doSend($data, $written));
+    }
+    
+    private function doSend(string $data, int $written): \Generator {
+        $deferred = new Deferred;
+        $this->writes->push([$data, $written, $deferred]);
+    
+        Loop::enable($this->writeWatcher);
+    
+        try {
+            $written = yield $deferred->getAwaitable();
+        } catch (\Throwable $exception) {
+            $this->close();
+            throw $exception;
+        } finally {
+            if ($this->writes->isEmpty()) {
+                Loop::disable($this->writeWatcher);
+            }
+        }
+    
+        return $written;
+    }
+}

lib/Threading/Internal/Thread.php

@@ -4,8 +4,7 @@ namespace Amp\Parallel\Threading\Internal;
 
 use Amp\Coroutine;
 use Amp\Parallel\{ ChannelException, SerializationException };
-use Amp\Parallel\Sync\{ Channel, ChannelledStream, Internal\ExitFailure, Internal\ExitSuccess };
+use Amp\Parallel\Sync\{ Channel, ChannelledSocket, Internal\ExitFailure, Internal\ExitSuccess };
-use Amp\Socket\Socket;
 use Interop\Async\Awaitable;
 
 /**
@@ -76,7 +75,7 @@ class Thread extends \Thread {
 
         try {
             \Amp\execute(function () {
-                $channel = new ChannelledStream(new Socket($this->socket, false));
+                $channel = new ChannelledSocket($this->socket, $this->socket, false);
         
                 $watcher = \Amp\repeat(self::KILL_CHECK_FREQUENCY, function () {
                     if ($this->killed) {

lib/Threading/Thread.php

@@ -4,8 +4,7 @@ namespace Amp\Parallel\Threading;
 
 use Amp\Coroutine;
 use Amp\Parallel\{ ContextException, StatusError, SynchronizationError, Strand };
-use Amp\Parallel\Sync\{ ChannelledStream, Internal\ExitStatus };
+use Amp\Parallel\Sync\{ ChannelledSocket, Internal\ExitStatus };
-use Amp\Socket\Socket;
 use Interop\Async\Awaitable;
 
 /**
@@ -19,12 +18,9 @@ class Thread implements Strand {
     /** @var Internal\Thread An internal thread instance. */
     private $thread;
 
-    /** @var \Amp\Parallel\Sync\Channel A channel for communicating with the thread. */
+    /** @var \Amp\Parallel\Sync\ChannelledSocket A channel for communicating with the thread. */
     private $channel;
 
-    /** @var \Amp\Socket\Socket */
-    private $pipe;
-
     /** @var resource */
     private $socket;
 
@@ -82,7 +78,6 @@ class Thread implements Strand {
     public function __clone() {
         $this->thread = null;
         $this->socket = null;
-        $this->pipe = null;
         $this->channel = null;
         $this->oid = 0;
     }
@@ -104,7 +99,7 @@ class Thread implements Strand {
      * @return bool True if the context is running, otherwise false.
      */
     public function isRunning(): bool {
-        return null !== $this->pipe && $this->pipe->isReadable();
+        return $this->channel !== null;
     }
 
     /**
@@ -120,7 +115,21 @@ class Thread implements Strand {
 
         $this->oid = \getmypid();
 
-        list($channel, $this->socket) = \Amp\Socket\pair();
+        $sockets = @\stream_socket_pair(
+            \stripos(PHP_OS, "win") === 0 ? STREAM_PF_INET : STREAM_PF_UNIX,
+            STREAM_SOCK_STREAM,
+            STREAM_IPPROTO_IP
+        );
+
+        if ($sockets === false) {
+            $message = "Failed to create socket pair";
+            if ($error = \error_get_last()) {
+                $message .= \sprintf(" Errno: %d; %s", $error["type"], $error["message"]);
+            }
+            throw new ContextException($message);
+        }
+
+        list($channel, $this->socket) = $sockets;
 
         $this->thread = new Internal\Thread($this->socket, $this->function, $this->args);
 
@@ -128,7 +137,7 @@ class Thread implements Strand {
             throw new ContextException('Failed to start the thread.');
         }
 
-        $this->channel = new ChannelledStream($this->pipe = new Socket($channel));
+        $this->channel = new ChannelledSocket($channel, $channel);
     }
 
     /**
@@ -152,8 +161,8 @@ class Thread implements Strand {
      * Closes channel and socket if still open.
      */
     private function close() {
-        if ($this->pipe !== null && $this->pipe->isReadable()) {
+        if ($this->channel !== null) {
-            $this->pipe->close();
+            $this->channel->close();
         }
 
         if (\is_resource($this->socket)) {

test/Sync/AbstractSemaphoreTest.php

@@ -2,7 +2,6 @@
 
 namespace Amp\Parallel\Test\Sync;
 
-use Amp\Parallel\Sync\Lock;
 use Amp\Parallel\Test\TestCase;
 use Amp\Pause;
 

test/Sync/ChannelledSocketTest.php

@@ -0,0 +1,121 @@
+<?php declare(strict_types = 1);
+
+namespace Amp\Parallel\Test\Sync;
+
+use Amp\Parallel\Sync\ChannelledSocket;
+use Amp\Parallel\Test\TestCase;
+
+class ChannelledSocketTest extends TestCase {
+    /**
+     * @return resource[]
+     */
+    protected function createSockets() {
+        if (($sockets = @\stream_socket_pair(\stripos(PHP_OS, "win") === 0 ? STREAM_PF_INET : STREAM_PF_UNIX, STREAM_SOCK_STREAM, STREAM_IPPROTO_IP)) === false) {
+            $message = "Failed to create socket pair";
+            if ($error = \error_get_last()) {
+                $message .= \sprintf(" Errno: %d; %s", $error["type"], $error["message"]);
+            }
+            $this->fail($message);
+        }
+        return $sockets;
+    }
+    
+    public function testSendReceive() {
+        \Amp\execute(function () {
+            list($left, $right) = $this->createSockets();
+            $a = new ChannelledSocket($left, $left);
+            $b = new ChannelledSocket($right, $right);
+
+            $message = 'hello';
+
+            yield $a->send($message);
+            $data = yield $b->receive();
+            $this->assertSame($message, $data);
+        });
+    }
+
+    /**
+     * @depends testSendReceive
+     */
+    public function testSendReceiveLongData() {
+        \Amp\execute(function () {
+            list($left, $right) = $this->createSockets();
+            $a = new ChannelledSocket($left, $left);
+            $b = new ChannelledSocket($right, $right);
+
+            $length = 0xffff;
+            $message = '';
+            for ($i = 0; $i < $length; ++$i) {
+                $message .= chr(mt_rand(0, 255));
+            }
+
+            $a->send($message);
+            $data = yield $b->receive();
+            $this->assertSame($message, $data);
+        });
+
+    }
+
+    /**
+     * @depends testSendReceive
+     * @expectedException \Amp\Parallel\ChannelException
+     */
+    public function testInvalidDataReceived() {
+        \Amp\execute(function () {
+            list($left, $right) = $this->createSockets();
+            $a = new ChannelledSocket($left, $left);
+            $b = new ChannelledSocket($right, $right);
+
+            fwrite($left, pack('L', 10) . '1234567890');
+            $data = yield $b->receive();
+        });
+
+    }
+
+    /**
+     * @depends testSendReceive
+     * @expectedException \Amp\Parallel\ChannelException
+     */
+    public function testSendUnserializableData() {
+        \Amp\execute(function () {
+            list($left, $right) = $this->createSockets();
+            $a = new ChannelledSocket($left, $left);
+            $b = new ChannelledSocket($right, $right);
+
+            // Close $a. $b should close on next read...
+            yield $a->send(function () {});
+            $data = yield $b->receive();
+        });
+
+    }
+
+    /**
+     * @depends testSendReceive
+     * @expectedException \Amp\Parallel\ChannelException
+     */
+    public function testSendAfterClose() {
+        \Amp\execute(function () {
+            list($left, $right) = $this->createSockets();
+            $a = new ChannelledSocket($left, $left);
+            $a->close();
+
+            yield $a->send('hello');
+        });
+
+    }
+
+    /**
+     * @depends testSendReceive
+     * @expectedException \Amp\Parallel\ChannelException
+     */
+    public function testReceiveAfterClose() {
+        \Amp\execute(function () {
+            list($left, $right) = $this->createSockets();
+            $a = new ChannelledSocket($left, $left);
+            $a->close();
+
+            $data = yield $a->receive();
+        });
+
+    }
+}

test/Sync/PosixSemaphoreTest.php

@@ -3,7 +3,7 @@
 namespace Amp\Parallel\Test\Sync;
 
 use Amp\Parallel\Forking\Fork;
-use Amp\Parallel\Sync\{PosixSemaphore, Semaphore};
+use Amp\Parallel\Sync\{ PosixSemaphore, Semaphore };
 
 /**
  * @group posix