<?php

/*
* This file is part of the Symfony package.
*
* (c) Fabien Potencier <fabien@symfony.com>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/

namespace Symfony\Component\Process\Pipes;

use Symfony\Component\Process\Process;

/**
* UnixPipes implementation uses unix pipes as handles.
*
* @author Romain Neutron <imprec@gmail.com>
*
* @internal
*/
class UnixPipes extends AbstractPipes
{
/** @var bool */
private $ttyMode;
/** @var bool */
private $ptyMode;
/** @var bool */
private $haveReadSupport;

public function __construct($ttyMode, $ptyMode, $input, $haveReadSupport)
{
$this->ttyMode = (bool) $ttyMode;
$this->ptyMode = (bool) $ptyMode;
$this->haveReadSupport = (bool) $haveReadSupport;

parent::__construct($input);
}

public function __destruct()
{
$this->close();
}

/**
* {@inheritdoc}
*/
public function getDescriptors()
{
if (!$this->haveReadSupport) {
$nullstream = fopen('/dev/null', 'c');

return array(
array('pipe', 'r'),
$nullstream,
$nullstream,
);
}

if ($this->ttyMode) {
return array(
array('file', '/dev/tty', 'r'),
array('file', '/dev/tty', 'w'),
array('file', '/dev/tty', 'w'),
);
}

if ($this->ptyMode && Process::isPtySupported()) {
return array(
array('pty'),
array('pty'),
array('pty'),
);
}

return array(
array('pipe', 'r'),
array('pipe', 'w'), // stdout
array('pipe', 'w'), // stderr
);
}

/**
* {@inheritdoc}
*/
public function getFiles()
{
return array();
}

/**
* {@inheritdoc}
*/
public function readAndWrite($blocking, $close = false)
{
$this->unblock();
$w = $this->write();

$read = $e = array();
$r = $this->pipes;
unset($r[0]);

// let's have a look if something changed in streams
if (($r || $w) && false === $n = @stream_select($r, $w, $e, 0, $blocking ? Process::TIMEOUT_PRECISION * 1E6 : 0)) {
// if a system call has been interrupted, forget about it, let's try again
// otherwise, an error occurred, let's reset pipes
if (!$this->hasSystemCallBeenInterrupted()) {
$this->pipes = array();
}

return $read;
}

foreach ($r as $pipe) {
// prior PHP 5.4 the array passed to stream_select is modified and
// lose key association, we have to find back the key
$read[$type = array_search($pipe, $this->pipes, true)] = '';

do {
$data = fread($pipe, self::CHUNK_SIZE);
$read[$type] .= $data;
} while (isset($data[0]) && ($close || isset($data[self::CHUNK_SIZE - 1])));

if (!isset($read[$type][0])) {
unset($read[$type]);
}

if ($close && feof($pipe)) {
fclose($pipe);
unset($this->pipes[$type]);
}
}

return $read;
}

/**
* {@inheritdoc}
*/
public function haveReadSupport()
{
return $this->haveReadSupport;
}

/**
* {@inheritdoc}
*/
public function areOpen()
{
return (bool) $this->pipes;
}
}