public function __construct($name, $pid, Error $error = null)
{
$this->name = $name;
$this->pid = $pid;
$this->error = $error;
if ($error) {
if (__CLASS__ === $error->getClass()) {
parent::__construct(sprintf('%s via "%s" fork (%d)', $error->getMessage(), $name, $pid));
} else {
parent::__construct(sprintf('%s (%d) thrown in "%s" fork (%d): "%s" (%s:%d)', $error->getClass(), $error->getCode(), $name, $pid, $error->getMessage(), $error->getFile(), $error->getLine()));
}
} else {
parent::__construct(sprintf('An unknown error occurred in "%s" fork (%d)', $name, $pid));
}
}
/**
* Forks something into another process and returns a deferred object.
*/
public function fork($callable)
{
if (!is_callable($callable)) {
throw new UnexpectedTypeException($callable, 'callable');
}
// allow the system to cleanup before forking
$this->dispatcher->dispatch(Events::PRE_FORK);
if (-1 === ($pid = pcntl_fork())) {
throw new ProcessControlException('Unable to fork a new process');
}
if (0 === $pid) {
// reset the list of child processes
$this->forks = array();
// setup the fifo (blocks until parent connects)
$fifo = new Fifo(null, $this->signal);
$message = new ExitMessage();
// phone home on shutdown
register_shutdown_function(function () use(&$fifo, &$message) {
$status = null;
try {
$fifo->send($message, false);
} catch (\Exception $e) {
// probably an error serializing the result
$message->setResult(null);
$message->setError(Error::fromException($e));
$fifo->send($message, false);
exit(2);
}
});
// dispatch an event so the system knows it's in a new process
$this->dispatcher->dispatch(Events::POST_FORK);
if (!$this->debug) {
ob_start();
}
try {
$result = call_user_func($callable, $fifo);
$message->setResult($result);
$status = is_integer($result) ? $result : 0;
} catch (\Exception $e) {
$message->setError(Error::fromException($e));
$status = 1;
}
if (!$this->debug) {
$message->setOutput(ob_get_clean());
}
exit($status);
}
// connect to the fifo
$fifo = new Fifo($pid);
return $this->forks[$pid] = new Fork($pid, $fifo, $this->debug);
}
