<?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;
use Symfony\Component\Process\Exception\RuntimeException;
/**
* ProcessPipes manages descriptors and pipes for the use of proc_open.
*/
class ProcessPipes
{
/** @var array */
public $pipes = array();
/** @var array */
private $files = array();
/** @var array */
private $fileHandles = array();
/** @var array */
private $readBytes = array();
/** @var bool */
private $useFiles;
/** @var bool */
private $ttyMode;
const CHUNK_SIZE = 16384;
public function __construct($useFiles, $ttyMode)
{
$this->useFiles = (bool) $useFiles;
$this->ttyMode = (bool) $ttyMode;
// Fix for PHP bug #51800: reading from STDOUT pipe hangs forever on Windows if the output is too big.
// Workaround for this problem is to use temporary files instead of pipes on Windows platform.
//
// @see https://bugs.php.net/bug.php?id=51800
if ($this->useFiles) {
$this->files = array(
Process::STDOUT => tempnam(sys_get_temp_dir(), 'sf_proc_stdout'),
Process::STDERR => tempnam(sys_get_temp_dir(), 'sf_proc_stderr'),
);
foreach ($this->files as $offset => $file) {
$this->fileHandles[$offset] = fopen($this->files[$offset], 'rb');
if (false === $this->fileHandles[$offset]) {
throw new RuntimeException('A temporary file could not be opened to write the process output to, verify that your TEMP environment variable is writable');
}
}
$this->readBytes = array(
Process::STDOUT => 0,
Process::STDERR => 0,
);
}
}
public function __destruct()
{
$this->close();
$this->removeFiles();
}
/**
* Sets non-blocking mode on pipes.
*/
public function unblock()
{
foreach ($this->pipes as $pipe) {
stream_set_blocking($pipe, 0);
}
}
/**
* Closes file handles and pipes.
*/
public function close()
{
$this->closeUnixPipes();
foreach ($this->fileHandles as $handle) {
fclose($handle);
}
$this->fileHandles = array();
}
/**
* Closes Unix pipes.
*
* Nothing happens in case file handles are used.
*/
public function closeUnixPipes()
{
foreach ($this->pipes as $pipe) {
fclose($pipe);
}
$this->pipes = array();
}
/**
* Returns an array of descriptors for the use of proc_open.
*
* @return array
*/
public function getDescriptors()
{
if ($this->useFiles) {
// We're not using pipe on Windows platform as it hangs (https://bugs.php.net/bug.php?id=51800)
// We're not using file handles as it can produce corrupted output https://bugs.php.net/bug.php?id=65650
// So we redirect output within the commandline and pass the nul device to the process
return array(
array('pipe', 'r'),
array('file', 'NUL', 'w'),
array('file', 'NUL', 'w'),
);
}
if ($this->ttyMode) {
return array(
array('file', '/dev/tty', 'r'),
array('file', '/dev/tty', 'w'),
array('file', '/dev/tty', 'w'),
);
}
return array(
array('pipe', 'r'), // stdin
array('pipe', 'w'), // stdout
array('pipe', 'w'), // stderr
);
}
/**
* Returns an array of filenames indexed by their related stream in case these pipes use temporary files.
*
* @return array
*/
public function getFiles()
{
if ($this->useFiles) {
return $this->files;
}
return array();
}
/**
* Reads data in file handles and pipes.
*
* @param bool $blocking Whether to use blocking calls or not.
*
* @return array An array of read data indexed by their fd.
*/
public function read($blocking)
{
return array_replace($this->readStreams($blocking), $this->readFileHandles());
}
/**
* Reads data in file handles and pipes, closes them if EOF is reached.
*
* @param bool $blocking Whether to use blocking calls or not.
*
* @return array An array of read data indexed by their fd.
*/
public function readAndCloseHandles($blocking)
{
return array_replace($this->readStreams($blocking, true), $this->readFileHandles(true));
}
/**
* Returns if the current state has open file handles or pipes.
*
* @return bool
*/
public function hasOpenHandles()
{
if (!$this->useFiles) {
return (bool) $this->pipes;
}
return (bool) $this->pipes && (bool) $this->fileHandles;
}
/**
* Writes stdin data.
*
* @param bool $blocking Whether to use blocking calls or not.
* @param string|null $stdin The data to write.
*/
public function write($blocking, $stdin)
{
if (null === $stdin) {
fclose($this->pipes[0]);
unset($this->pipes[0]);
return;
}
$writePipes = array($this->pipes[0]);
unset($this->pipes[0]);
$stdinLen = strlen($stdin);
$stdinOffset = 0;
while ($writePipes) {
$r = null;
$w = $writePipes;
$e = null;
if (false === $n = @stream_select($r, $w, $e, 0, $blocking ? ceil(Process::TIMEOUT_PRECISION * 1E6) : 0)) {
// if a system call has been interrupted, forget about it, let's try again
if ($this->hasSystemCallBeenInterrupted()) {
continue;
}
break;
}
// nothing has changed, let's wait until the process is ready
if (0 === $n) {
continue;
}
if ($w) {
$written = fwrite($writePipes[0], (binary) substr($stdin, $stdinOffset), 8192);
if (false !== $written) {
$stdinOffset += $written;
}
if ($stdinOffset >= $stdinLen) {
fclose($writePipes[0]);
$writePipes = null;
}
}
}
}
/**
* Reads data in file handles.
*
* @param bool $close Whether to close file handles or not.
*
* @return array An array of read data indexed by their fd.
*/
private function readFileHandles($close = false)
{
$read = array();
$fh = $this->fileHandles;
foreach ($fh as $type => $fileHandle) {
if (0 !== fseek($fileHandle, $this->readBytes[$type])) {
continue;
}
$data = '';
$dataread = null;
while (!feof($fileHandle)) {
if (false !== $dataread = fread($fileHandle, self::CHUNK_SIZE)) {
$data .= $dataread;
}
}
if (0 < $length = strlen($data)) {
$this->readBytes[$type] += $length;
$read[$type] = $data;
}
if (false === $dataread || (true === $close && feof($fileHandle) && '' === $data)) {
fclose($this->fileHandles[$type]);
unset($this->fileHandles[$type]);
}
}
return $read;
}
/**
* Reads data in file pipes streams.
*
* @param bool $blocking Whether to use blocking calls or not.
* @param bool $close Whether to close file handles or not.
*
* @return array An array of read data indexed by their fd.
*/
private function readStreams($blocking, $close = false)
{
if (empty($this->pipes)) {
return array();
}
$read = array();
$r = $this->pipes;
$w = null;
$e = null;
// let's have a look if something changed in streams
if (false === $n = @stream_select($r, $w, $e, 0, $blocking ? ceil(Process::TIMEOUT_PRECISION * 1E6) : 0)) {
// if a system call has been interrupted, forget about it, let's try again
// otherwise, an error occurred, let's reset pipes
if (!$this->hasSystemCallBeenInterrupted()) {
$this->pipes = array();
}
return $read;
}
// nothing has changed
if (0 === $n) {
return $read;
}
foreach ($r as $pipe) {
$type = array_search($pipe, $this->pipes);
$data = '';
while ($dataread = fread($pipe, self::CHUNK_SIZE)) {
$data .= $dataread;
}
if ($data) {
$read[$type] = $data;
}
if (false === $data || (true === $close && feof($pipe) && '' === $data)) {
fclose($this->pipes[$type]);
unset($this->pipes[$type]);
}
}
return $read;
}
/**
* Returns true if a system call has been interrupted.
*
* @return bool
*/
private function hasSystemCallBeenInterrupted()
{
$lastError = error_get_last();
// stream_select returns false when the `select` system call is interrupted by an incoming signal
return isset($lastError['message']) && false !== stripos($lastError['message'], 'interrupted system call');
}
/**
* Removes temporary files
*/
private function removeFiles()
{
foreach ($this->files as $filename) {
if (file_exists($filename)) {
@unlink($filename);
}
}
$this->files = array();
}
}