comparison vendor/symfony/process/Process.php @ 0:c75dbcec494b

Initial commit from drush-created site

+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <[e-mail]>
+ *
+ * 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\InvalidArgumentException;
+use Symfony\Component\Process\Exception\LogicException;
+use Symfony\Component\Process\Exception\ProcessFailedException;
+use Symfony\Component\Process\Exception\ProcessTimedOutException;
+use Symfony\Component\Process\Exception\RuntimeException;
+use Symfony\Component\Process\Pipes\PipesInterface;
+use Symfony\Component\Process\Pipes\UnixPipes;
+use Symfony\Component\Process\Pipes\WindowsPipes;
+
+/**
+ * Process is a thin wrapper around proc_* functions to easily
+ * start independent PHP processes.
+ *
+ * @author Fabien Potencier <[e-mail]>
+ * @author Romain Neutron <[e-mail]>
+ */
+class Process implements \IteratorAggregate
+{
+    const ERR = 'err';
+    const OUT = 'out';
+
+    const STATUS_READY = 'ready';
+    const STATUS_STARTED = 'started';
+    const STATUS_TERMINATED = 'terminated';
+
+    const STDIN = 0;
+    const STDOUT = 1;
+    const STDERR = 2;
+
+    // Timeout Precision in seconds.
+    const TIMEOUT_PRECISION = 0.2;
+
+    const ITER_NON_BLOCKING = 1; // By default, iterating over outputs is a blocking call, use this flag to make it non-blocking
+    const ITER_KEEP_OUTPUT = 2;  // By default, outputs are cleared while iterating, use this flag to keep them in memory
+    const ITER_SKIP_OUT = 4;     // Use this flag to skip STDOUT while iterating
+    const ITER_SKIP_ERR = 8;     // Use this flag to skip STDERR while iterating
+
+    private $callback;
+    private $hasCallback = false;
+    private $commandline;
+    private $cwd;
+    private $env;
+    private $input;
+    private $starttime;
+    private $lastOutputTime;
+    private $timeout;
+    private $idleTimeout;
+    private $options = array('suppress_errors' => true);
+    private $exitcode;
+    private $fallbackStatus = array();
+    private $processInformation;
+    private $outputDisabled = false;
+    private $stdout;
+    private $stderr;
+    private $enhanceWindowsCompatibility = true;
+    private $enhanceSigchildCompatibility;
+    private $process;
+    private $status = self::STATUS_READY;
+    private $incrementalOutputOffset = 0;
+    private $incrementalErrorOutputOffset = 0;
+    private $tty;
+    private $pty;
+    private $inheritEnv = false;
+
+    private $useFileHandles = false;
+    /** @var PipesInterface */
+    private $processPipes;
+
+    private $latestSignal;
+
+    private static $sigchild;
+
+    /**
+     * Exit codes translation table.
+     *
+     * User-defined errors must use exit codes in the 64-113 range.
+     */
+    public static $exitCodes = array(
+        0 => 'OK',
+        1 => 'General error',
+        2 => 'Misuse of shell builtins',
+
+        126 => 'Invoked command cannot execute',
+        127 => 'Command not found',
+        128 => 'Invalid exit argument',
+
+        // signals
+        129 => 'Hangup',
+        130 => 'Interrupt',
+        131 => 'Quit and dump core',
+        132 => 'Illegal instruction',
+        133 => 'Trace/breakpoint trap',
+        134 => 'Process aborted',
+        135 => 'Bus error: "access to undefined portion of memory object"',
+        136 => 'Floating point exception: "erroneous arithmetic operation"',
+        137 => 'Kill (terminate immediately)',
+        138 => 'User-defined 1',
+        139 => 'Segmentation violation',
+        140 => 'User-defined 2',
+        141 => 'Write to pipe with no one reading',
+        142 => 'Signal raised by alarm',
+        143 => 'Termination (request to terminate)',
+        // 144 - not defined
+        145 => 'Child process terminated, stopped (or continued*)',
+        146 => 'Continue if stopped',
+        147 => 'Stop executing temporarily',
+        148 => 'Terminal stop signal',
+        149 => 'Background process attempting to read from tty ("in")',
+        150 => 'Background process attempting to write to tty ("out")',
+        151 => 'Urgent data available on socket',
+        152 => 'CPU time limit exceeded',
+        153 => 'File size limit exceeded',
+        154 => 'Signal raised by timer counting virtual time: "virtual timer expired"',
+        155 => 'Profiling timer expired',
+        // 156 - not defined
+        157 => 'Pollable event',
+        // 158 - not defined
+        159 => 'Bad syscall',
+    );
+
+    /**
+     * @param string|array   $commandline The command line to run
+     * @param string|null    $cwd         The working directory or null to use the working dir of the current PHP process
+     * @param array|null     $env         The environment variables or null to use the same environment as the current PHP process
+     * @param mixed|null     $input       The input as stream resource, scalar or \Traversable, or null for no input
+     * @param int|float|null $timeout     The timeout in seconds or null to disable
+     * @param array          $options     An array of options for proc_open
+     *
+     * @throws RuntimeException When proc_open is not installed
+     */
+    public function __construct($commandline, $cwd = null, array $env = null, $input = null, $timeout = 60, array $options = null)
+    {
+        if (!function_exists('proc_open')) {
+            throw new RuntimeException('The Process class relies on proc_open, which is not available on your PHP installation.');
+        }
+
+        $this->commandline = $commandline;
+        $this->cwd = $cwd;
+
+        // on Windows, if the cwd changed via chdir(), proc_open defaults to the dir where PHP was started
+        // on Gnu/Linux, PHP builds with --enable-maintainer-zts are also affected
+        // @see : https://bugs.php.net/bug.php?id=51800
+        // @see : https://bugs.php.net/bug.php?id=50524
+        if (null === $this->cwd && (defined('ZEND_THREAD_SAFE') || '\\' === DIRECTORY_SEPARATOR)) {
+            $this->cwd = getcwd();
+        }
+        if (null !== $env) {
+            $this->setEnv($env);
+        }
+
+        $this->setInput($input);
+        $this->setTimeout($timeout);
+        $this->useFileHandles = '\\' === DIRECTORY_SEPARATOR;
+        $this->pty = false;
+        $this->enhanceSigchildCompatibility = '\\' !== DIRECTORY_SEPARATOR && $this->isSigchildEnabled();
+        if (null !== $options) {
+            @trigger_error(sprintf('The $options parameter of the %s constructor is deprecated since Symfony 3.3 and will be removed in 4.0.', __CLASS__), E_USER_DEPRECATED);
+            $this->options = array_replace($this->options, $options);
+        }
+    }
+
+    public function __destruct()
+    {
+        $this->stop(0);
+    }
+
+    public function __clone()
+    {
+        $this->resetProcessData();
+    }
+
+    /**
+     * Runs the process.
+     *
+     * The callback receives the type of output (out or err) and
+     * some bytes from the output in real-time. It allows to have feedback
+     * from the independent process during execution.
+     *
+     * The STDOUT and STDERR are also available after the process is finished
+     * via the getOutput() and getErrorOutput() methods.
+     *
+     * @param callable|null $callback A PHP callback to run whenever there is some
+     *                                output available on STDOUT or STDERR
+     * @param array         $env      An array of additional env vars to set when running the process
+     *
+     * @return int The exit status code
+     *
+     * @throws RuntimeException When process can't be launched
+     * @throws RuntimeException When process stopped after receiving signal
+     * @throws LogicException   In case a callback is provided and output has been disabled
+     *
+     * @final since version 3.3
+     */
+    public function run($callback = null/*, array $env = array()*/)
+    {
+        $env = 1 < func_num_args() ? func_get_arg(1) : null;
+        $this->start($callback, $env);
+
+        return $this->wait();
+    }
+
+    /**
+     * Runs the process.
+     *
+     * This is identical to run() except that an exception is thrown if the process
+     * exits with a non-zero exit code.
+     *
+     * @param callable|null $callback
+     * @param array         $env      An array of additional env vars to set when running the process
+     *
+     * @return self
+     *
+     * @throws RuntimeException       if PHP was compiled with --enable-sigchild and the enhanced sigchild compatibility mode is not enabled
+     * @throws ProcessFailedException if the process didn't terminate successfully
+     *
+     * @final since version 3.3
+     */
+    public function mustRun(callable $callback = null/*, array $env = array()*/)
+    {
+        if (!$this->enhanceSigchildCompatibility && $this->isSigchildEnabled()) {
+            throw new RuntimeException('This PHP has been compiled with --enable-sigchild. You must use setEnhanceSigchildCompatibility() to use this method.');
+        }
+        $env = 1 < func_num_args() ? func_get_arg(1) : null;
+
+        if (0 !== $this->run($callback, $env)) {
+            throw new ProcessFailedException($this);
+        }
+
+        return $this;
+    }
+
+    /**
+     * Starts the process and returns after writing the input to STDIN.
+     *
+     * This method blocks until all STDIN data is sent to the process then it
+     * returns while the process runs in the background.
+     *
+     * The termination of the process can be awaited with wait().
+     *
+     * The callback receives the type of output (out or err) and some bytes from
+     * the output in real-time while writing the standard input to the process.
+     * It allows to have feedback from the independent process during execution.
+     *
+     * @param callable|null $callback A PHP callback to run whenever there is some
+     *                                output available on STDOUT or STDERR
+     * @param array         $env      An array of additional env vars to set when running the process
+     *
+     * @throws RuntimeException When process can't be launched
+     * @throws RuntimeException When process is already running
+     * @throws LogicException   In case a callback is provided and output has been disabled
+     */
+    public function start(callable $callback = null/*, array $env = array()*/)
+    {
+        if ($this->isRunning()) {
+            throw new RuntimeException('Process is already running');
+        }
+        if (2 <= func_num_args()) {
+            $env = func_get_arg(1);
+        } else {
+            if (__CLASS__ !== static::class) {
+                $r = new \ReflectionMethod($this, __FUNCTION__);
+                if (__CLASS__ !== $r->getDeclaringClass()->getName() && (2 > $r->getNumberOfParameters() || 'env' !== $r->getParameters()[0]->name)) {
+                    @trigger_error(sprintf('The %s::start() method expects a second "$env" argument since Symfony 3.3. It will be made mandatory in 4.0.', static::class), E_USER_DEPRECATED);
+                }
+            }
+            $env = null;
+        }
+
+        $this->resetProcessData();
+        $this->starttime = $this->lastOutputTime = microtime(true);
+        $this->callback = $this->buildCallback($callback);
+        $this->hasCallback = null !== $callback;
+        $descriptors = $this->getDescriptors();
+        $inheritEnv = $this->inheritEnv;
+
+        if (is_array($commandline = $this->commandline)) {
+            $commandline = implode(' ', array_map(array($this, 'escapeArgument'), $commandline));
+
+            if ('\\' !== DIRECTORY_SEPARATOR) {
+                // exec is mandatory to deal with sending a signal to the process
+                $commandline = 'exec '.$commandline;
+            }
+        }
+
+        if (null === $env) {
+            $env = $this->env;
+        } else {
+            if ($this->env) {
+                $env += $this->env;
+            }
+            $inheritEnv = true;
+        }
+
+        if (null !== $env && $inheritEnv) {
+            $env += $this->getDefaultEnv();
+        } elseif (null !== $env) {
+            @trigger_error('Not inheriting environment variables is deprecated since Symfony 3.3 and will always happen in 4.0. Set "Process::inheritEnvironmentVariables()" to true instead.', E_USER_DEPRECATED);
+        } else {
+            $env = $this->getDefaultEnv();
+        }
+        if ('\\' === DIRECTORY_SEPARATOR && $this->enhanceWindowsCompatibility) {
+            $this->options['bypass_shell'] = true;
+            $commandline = $this->prepareWindowsCommandLine($commandline, $env);
+        } elseif (!$this->useFileHandles && $this->enhanceSigchildCompatibility && $this->isSigchildEnabled()) {
+            // last exit code is output on the fourth pipe and caught to work around --enable-sigchild
+            $descriptors[3] = array('pipe', 'w');
+
+            // See https://unix.stackexchange.com/questions/71205/background-process-pipe-input
+            $commandline = '{ ('.$commandline.') <&3 3<&- 3>/dev/null & } 3<&0;';
+            $commandline .= 'pid=$!; echo $pid >&3; wait $pid; code=$?; echo $code >&3; exit $code';
+
+            // Workaround for the bug, when PTS functionality is enabled.
+            // @see : https://bugs.php.net/69442
+            $ptsWorkaround = fopen(__FILE__, 'r');
+        }
+        if (defined('HHVM_VERSION')) {
+            $envPairs = $env;
+        } else {
+            $envPairs = array();
+            foreach ($env as $k => $v) {
+                if (false !== $v) {
+                    $envPairs[] = $k.'='.$v;
+                }
+            }
+        }
+
+        if (!is_dir($this->cwd)) {
+            @trigger_error('The provided cwd does not exist. Command is currently ran against getcwd(). This behavior is deprecated since Symfony 3.4 and will be removed in 4.0.', E_USER_DEPRECATED);
+        }
+
+        $this->process = proc_open($commandline, $descriptors, $this->processPipes->pipes, $this->cwd, $envPairs, $this->options);
+
+        if (!is_resource($this->process)) {
+            throw new RuntimeException('Unable to launch a new process.');
+        }
+        $this->status = self::STATUS_STARTED;
+
+        if (isset($descriptors[3])) {
+            $this->fallbackStatus['pid'] = (int) fgets($this->processPipes->pipes[3]);
+        }
+
+        if ($this->tty) {
+            return;
+        }
+
+        $this->updateStatus(false);
+        $this->checkTimeout();
+    }
+
+    /**
+     * Restarts the process.
+     *
+     * Be warned that the process is cloned before being started.
+     *
+     * @param callable|null $callback A PHP callback to run whenever there is some
+     *                                output available on STDOUT or STDERR
+     * @param array         $env      An array of additional env vars to set when running the process
+     *
+     * @return $this
+     *
+     * @throws RuntimeException When process can't be launched
+     * @throws RuntimeException When process is already running
+     *
+     * @see start()
+     *
+     * @final since version 3.3
+     */
+    public function restart(callable $callback = null/*, array $env = array()*/)
+    {
+        if ($this->isRunning()) {
+            throw new RuntimeException('Process is already running');
+        }
+        $env = 1 < func_num_args() ? func_get_arg(1) : null;
+
+        $process = clone $this;
+        $process->start($callback, $env);
+
+        return $process;
+    }
+
+    /**
+     * Waits for the process to terminate.
+     *
+     * The callback receives the type of output (out or err) and some bytes
+     * from the output in real-time while writing the standard input to the process.
+     * It allows to have feedback from the independent process during execution.
+     *
+     * @param callable|null $callback A valid PHP callback
+     *
+     * @return int The exitcode of the process
+     *
+     * @throws RuntimeException When process timed out
+     * @throws RuntimeException When process stopped after receiving signal
+     * @throws LogicException   When process is not yet started
+     */
+    public function wait(callable $callback = null)
+    {
+        $this->requireProcessIsStarted(__FUNCTION__);
+
+        $this->updateStatus(false);
+
+        if (null !== $callback) {
+            if (!$this->processPipes->haveReadSupport()) {
+                $this->stop(0);
+                throw new \LogicException('Pass the callback to the Process::start method or enableOutput to use a callback with Process::wait');
+            }
+            $this->callback = $this->buildCallback($callback);
+        }
+
+        do {
+            $this->checkTimeout();
+            $running = '\\' === DIRECTORY_SEPARATOR ? $this->isRunning() : $this->processPipes->areOpen();
+            $this->readPipes($running, '\\' !== DIRECTORY_SEPARATOR || !$running);
+        } while ($running);
+
+        while ($this->isRunning()) {
+            usleep(1000);
+        }
+
+        if ($this->processInformation['signaled'] && $this->processInformation['termsig'] !== $this->latestSignal) {
+            throw new RuntimeException(sprintf('The process has been signaled with signal "%s".', $this->processInformation['termsig']));
+        }
+
+        return $this->exitcode;
+    }
+
+    /**
+     * Returns the Pid (process identifier), if applicable.
+     *
+     * @return int|null The process id if running, null otherwise
+     */
+    public function getPid()
+    {
+        return $this->isRunning() ? $this->processInformation['pid'] : null;
+    }
+
+    /**
+     * Sends a POSIX signal to the process.
+     *
+     * @param int $signal A valid POSIX signal (see http://www.php.net/manual/en/pcntl.constants.php)
+     *
+     * @return $this
+     *
+     * @throws LogicException   In case the process is not running
+     * @throws RuntimeException In case --enable-sigchild is activated and the process can't be killed
+     * @throws RuntimeException In case of failure
+     */
+    public function signal($signal)
+    {
+        $this->doSignal($signal, true);
+
+        return $this;
+    }
+
+    /**
+     * Disables fetching output and error output from the underlying process.
+     *
+     * @return $this
+     *
+     * @throws RuntimeException In case the process is already running
+     * @throws LogicException   if an idle timeout is set
+     */
+    public function disableOutput()
+    {
+        if ($this->isRunning()) {
+            throw new RuntimeException('Disabling output while the process is running is not possible.');
+        }
+        if (null !== $this->idleTimeout) {
+            throw new LogicException('Output can not be disabled while an idle timeout is set.');
+        }
+
+        $this->outputDisabled = true;
+
+        return $this;
+    }
+
+    /**
+     * Enables fetching output and error output from the underlying process.
+     *
+     * @return $this
+     *
+     * @throws RuntimeException In case the process is already running
+     */
+    public function enableOutput()
+    {
+        if ($this->isRunning()) {
+            throw new RuntimeException('Enabling output while the process is running is not possible.');
+        }
+
+        $this->outputDisabled = false;
+
+        return $this;
+    }
+
+    /**
+     * Returns true in case the output is disabled, false otherwise.
+     *
+     * @return bool
+     */
+    public function isOutputDisabled()
+    {
+        return $this->outputDisabled;
+    }
+
+    /**
+     * Returns the current output of the process (STDOUT).
+     *
+     * @return string The process output
+     *
+     * @throws LogicException in case the output has been disabled
+     * @throws LogicException In case the process is not started
+     */
+    public function getOutput()
+    {
+        $this->readPipesForOutput(__FUNCTION__);
+
+        if (false === $ret = stream_get_contents($this->stdout, -1, 0)) {
+            return '';
+        }
+
+        return $ret;
+    }
+
+    /**
+     * Returns the output incrementally.
+     *
+     * In comparison with the getOutput method which always return the whole
+     * output, this one returns the new output since the last call.
+     *
+     * @return string The process output since the last call
+     *
+     * @throws LogicException in case the output has been disabled
+     * @throws LogicException In case the process is not started
+     */
+    public function getIncrementalOutput()
+    {
+        $this->readPipesForOutput(__FUNCTION__);
+
+        $latest = stream_get_contents($this->stdout, -1, $this->incrementalOutputOffset);
+        $this->incrementalOutputOffset = ftell($this->stdout);
+
+        if (false === $latest) {
+            return '';
+        }
+
+        return $latest;
+    }
+
+    /**
+     * Returns an iterator to the output of the process, with the output type as keys (Process::OUT/ERR).
+     *
+     * @param int $flags A bit field of Process::ITER_* flags
+     *
+     * @throws LogicException in case the output has been disabled
+     * @throws LogicException In case the process is not started
+     *
+     * @return \Generator
+     */
+    public function getIterator($flags = 0)
+    {
+        $this->readPipesForOutput(__FUNCTION__, false);
+
+        $clearOutput = !(self::ITER_KEEP_OUTPUT & $flags);
+        $blocking = !(self::ITER_NON_BLOCKING & $flags);
+        $yieldOut = !(self::ITER_SKIP_OUT & $flags);
+        $yieldErr = !(self::ITER_SKIP_ERR & $flags);
+
+        while (null !== $this->callback || ($yieldOut && !feof($this->stdout)) || ($yieldErr && !feof($this->stderr))) {
+            if ($yieldOut) {
+                $out = stream_get_contents($this->stdout, -1, $this->incrementalOutputOffset);
+
+                if (isset($out[0])) {
+                    if ($clearOutput) {
+                        $this->clearOutput();
+                    } else {
+                        $this->incrementalOutputOffset = ftell($this->stdout);
+                    }
+
+                    yield self::OUT => $out;
+                }
+            }
+
+            if ($yieldErr) {
+                $err = stream_get_contents($this->stderr, -1, $this->incrementalErrorOutputOffset);
+
+                if (isset($err[0])) {
+                    if ($clearOutput) {
+                        $this->clearErrorOutput();
+                    } else {
+                        $this->incrementalErrorOutputOffset = ftell($this->stderr);
+                    }
+
+                    yield self::ERR => $err;
+                }
+            }
+
+            if (!$blocking && !isset($out[0]) && !isset($err[0])) {
+                yield self::OUT => '';
+            }
+
+            $this->checkTimeout();
+            $this->readPipesForOutput(__FUNCTION__, $blocking);
+        }
+    }
+
+    /**
+     * Clears the process output.
+     *
+     * @return $this
+     */
+    public function clearOutput()
+    {
+        ftruncate($this->stdout, 0);
+        fseek($this->stdout, 0);
+        $this->incrementalOutputOffset = 0;
+
+        return $this;
+    }
+
+    /**
+     * Returns the current error output of the process (STDERR).
+     *
+     * @return string The process error output
+     *
+     * @throws LogicException in case the output has been disabled
+     * @throws LogicException In case the process is not started
+     */
+    public function getErrorOutput()
+    {
+        $this->readPipesForOutput(__FUNCTION__);
+
+        if (false === $ret = stream_get_contents($this->stderr, -1, 0)) {
+            return '';
+        }
+
+        return $ret;
+    }
+
+    /**
+     * Returns the errorOutput incrementally.
+     *
+     * In comparison with the getErrorOutput method which always return the
+     * whole error output, this one returns the new error output since the last
+     * call.
+     *
+     * @return string The process error output since the last call
+     *
+     * @throws LogicException in case the output has been disabled
+     * @throws LogicException In case the process is not started
+     */
+    public function getIncrementalErrorOutput()
+    {
+        $this->readPipesForOutput(__FUNCTION__);
+
+        $latest = stream_get_contents($this->stderr, -1, $this->incrementalErrorOutputOffset);
+        $this->incrementalErrorOutputOffset = ftell($this->stderr);
+
+        if (false === $latest) {
+            return '';
+        }
+
+        return $latest;
+    }
+
+    /**
+     * Clears the process output.
+     *
+     * @return $this
+     */
+    public function clearErrorOutput()
+    {
+        ftruncate($this->stderr, 0);
+        fseek($this->stderr, 0);
+        $this->incrementalErrorOutputOffset = 0;
+
+        return $this;
+    }
+
+    /**
+     * Returns the exit code returned by the process.
+     *
+     * @return null|int The exit status code, null if the Process is not terminated
+     *
+     * @throws RuntimeException In case --enable-sigchild is activated and the sigchild compatibility mode is disabled
+     */
+    public function getExitCode()
+    {
+        if (!$this->enhanceSigchildCompatibility && $this->isSigchildEnabled()) {
+            throw new RuntimeException('This PHP has been compiled with --enable-sigchild. You must use setEnhanceSigchildCompatibility() to use this method.');
+        }
+
+        $this->updateStatus(false);
+
+        return $this->exitcode;
+    }
+
+    /**
+     * Returns a string representation for the exit code returned by the process.
+     *
+     * This method relies on the Unix exit code status standardization
+     * and might not be relevant for other operating systems.
+     *
+     * @return null|string A string representation for the exit status code, null if the Process is not terminated
+     *
+     * @see http://tldp.org/LDP/abs/html/exitcodes.html
+     * @see http://en.wikipedia.org/wiki/Unix_signal
+     */
+    public function getExitCodeText()
+    {
+        if (null === $exitcode = $this->getExitCode()) {
+            return;
+        }
+
+        return isset(self::$exitCodes[$exitcode]) ? self::$exitCodes[$exitcode] : 'Unknown error';
+    }
+
+    /**
+     * Checks if the process ended successfully.
+     *
+     * @return bool true if the process ended successfully, false otherwise
+     */
+    public function isSuccessful()
+    {
+        return 0 === $this->getExitCode();
+    }
+
+    /**
+     * Returns true if the child process has been terminated by an uncaught signal.
+     *
+     * It always returns false on Windows.
+     *
+     * @return bool
+     *
+     * @throws RuntimeException In case --enable-sigchild is activated
+     * @throws LogicException   In case the process is not terminated
+     */
+    public function hasBeenSignaled()
+    {
+        $this->requireProcessIsTerminated(__FUNCTION__);
+
+        if (!$this->enhanceSigchildCompatibility && $this->isSigchildEnabled()) {
+            throw new RuntimeException('This PHP has been compiled with --enable-sigchild. Term signal can not be retrieved.');
+        }
+
+        return $this->processInformation['signaled'];
+    }
+
+    /**
+     * Returns the number of the signal that caused the child process to terminate its execution.
+     *
+     * It is only meaningful if hasBeenSignaled() returns true.
+     *
+     * @return int
+     *
+     * @throws RuntimeException In case --enable-sigchild is activated
+     * @throws LogicException   In case the process is not terminated
+     */
+    public function getTermSignal()
+    {
+        $this->requireProcessIsTerminated(__FUNCTION__);
+
+        if ($this->isSigchildEnabled() && (!$this->enhanceSigchildCompatibility || -1 === $this->processInformation['termsig'])) {
+            throw new RuntimeException('This PHP has been compiled with --enable-sigchild. Term signal can not be retrieved.');
+        }
+
+        return $this->processInformation['termsig'];
+    }
+
+    /**
+     * Returns true if the child process has been stopped by a signal.
+     *
+     * It always returns false on Windows.
+     *
+     * @return bool
+     *
+     * @throws LogicException In case the process is not terminated
+     */
+    public function hasBeenStopped()
+    {
+        $this->requireProcessIsTerminated(__FUNCTION__);
+
+        return $this->processInformation['stopped'];
+    }
+
+    /**
+     * Returns the number of the signal that caused the child process to stop its execution.
+     *
+     * It is only meaningful if hasBeenStopped() returns true.
+     *
+     * @return int
+     *
+     * @throws LogicException In case the process is not terminated
+     */
+    public function getStopSignal()
+    {
+        $this->requireProcessIsTerminated(__FUNCTION__);
+
+        return $this->processInformation['stopsig'];
+    }
+
+    /**
+     * Checks if the process is currently running.
+     *
+     * @return bool true if the process is currently running, false otherwise
+     */
+    public function isRunning()
+    {
+        if (self::STATUS_STARTED !== $this->status) {
+            return false;
+        }
+
+        $this->updateStatus(false);
+
+        return $this->processInformation['running'];
+    }
+
+    /**
+     * Checks if the process has been started with no regard to the current state.
+     *
+     * @return bool true if status is ready, false otherwise
+     */
+    public function isStarted()
+    {
+        return self::STATUS_READY != $this->status;
+    }
+
+    /**
+     * Checks if the process is terminated.
+     *
+     * @return bool true if process is terminated, false otherwise
+     */
+    public function isTerminated()
+    {
+        $this->updateStatus(false);
+
+        return self::STATUS_TERMINATED == $this->status;
+    }
+
+    /**
+     * Gets the process status.
+     *
+     * The status is one of: ready, started, terminated.
+     *
+     * @return string The current process status
+     */
+    public function getStatus()
+    {
+        $this->updateStatus(false);
+
+        return $this->status;
+    }
+
+    /**
+     * Stops the process.
+     *
+     * @param int|float $timeout The timeout in seconds
+     * @param int       $signal  A POSIX signal to send in case the process has not stop at timeout, default is SIGKILL (9)
+     *
+     * @return int The exit-code of the process
+     */
+    public function stop($timeout = 10, $signal = null)
+    {
+        $timeoutMicro = microtime(true) + $timeout;
+        if ($this->isRunning()) {
+            // given `SIGTERM` may not be defined and that `proc_terminate` uses the constant value and not the constant itself, we use the same here
+            $this->doSignal(15, false);
+            do {
+                usleep(1000);
+            } while ($this->isRunning() && microtime(true) < $timeoutMicro);
+
+            if ($this->isRunning()) {
+                // Avoid exception here: process is supposed to be running, but it might have stopped just
+                // after this line. In any case, let's silently discard the error, we cannot do anything.
+                $this->doSignal($signal ?: 9, false);
+            }
+        }
+
+        if ($this->isRunning()) {
+            if (isset($this->fallbackStatus['pid'])) {
+                unset($this->fallbackStatus['pid']);
+
+                return $this->stop(0, $signal);
+            }
+            $this->close();
+        }
+
+        return $this->exitcode;
+    }
+
+    /**
+     * Adds a line to the STDOUT stream.
+     *
+     * @internal
+     *
+     * @param string $line The line to append
+     */
+    public function addOutput($line)
+    {
+        $this->lastOutputTime = microtime(true);
+
+        fseek($this->stdout, 0, SEEK_END);
+        fwrite($this->stdout, $line);
+        fseek($this->stdout, $this->incrementalOutputOffset);
+    }
+
+    /**
+     * Adds a line to the STDERR stream.
+     *
+     * @internal
+     *
+     * @param string $line The line to append
+     */
+    public function addErrorOutput($line)
+    {
+        $this->lastOutputTime = microtime(true);
+
+        fseek($this->stderr, 0, SEEK_END);
+        fwrite($this->stderr, $line);
+        fseek($this->stderr, $this->incrementalErrorOutputOffset);
+    }
+
+    /**
+     * Gets the command line to be executed.
+     *
+     * @return string The command to execute
+     */
+    public function getCommandLine()
+    {
+        return is_array($this->commandline) ? implode(' ', array_map(array($this, 'escapeArgument'), $this->commandline)) : $this->commandline;
+    }
+
+    /**
+     * Sets the command line to be executed.
+     *
+     * @param string|array $commandline The command to execute
+     *
+     * @return self The current Process instance
+     */
+    public function setCommandLine($commandline)
+    {
+        $this->commandline = $commandline;
+
+        return $this;
+    }
+
+    /**
+     * Gets the process timeout (max. runtime).
+     *
+     * @return float|null The timeout in seconds or null if it's disabled
+     */
+    public function getTimeout()
+    {
+        return $this->timeout;
+    }
+
+    /**
+     * Gets the process idle timeout (max. time since last output).
+     *
+     * @return float|null The timeout in seconds or null if it's disabled
+     */
+    public function getIdleTimeout()
+    {
+        return $this->idleTimeout;
+    }
+
+    /**
+     * Sets the process timeout (max. runtime).
+     *
+     * To disable the timeout, set this value to null.
+     *
+     * @param int|float|null $timeout The timeout in seconds
+     *
+     * @return self The current Process instance
+     *
+     * @throws InvalidArgumentException if the timeout is negative
+     */
+    public function setTimeout($timeout)
+    {
+        $this->timeout = $this->validateTimeout($timeout);
+
+        return $this;
+    }
+
+    /**
+     * Sets the process idle timeout (max. time since last output).
+     *
+     * To disable the timeout, set this value to null.
+     *
+     * @param int|float|null $timeout The timeout in seconds
+     *
+     * @return self The current Process instance
+     *
+     * @throws LogicException           if the output is disabled
+     * @throws InvalidArgumentException if the timeout is negative
+     */
+    public function setIdleTimeout($timeout)
+    {
+        if (null !== $timeout && $this->outputDisabled) {
+            throw new LogicException('Idle timeout can not be set while the output is disabled.');
+        }
+
+        $this->idleTimeout = $this->validateTimeout($timeout);
+
+        return $this;
+    }
+
+    /**
+     * Enables or disables the TTY mode.
+     *
+     * @param bool $tty True to enabled and false to disable
+     *
+     * @return self The current Process instance
+     *
+     * @throws RuntimeException In case the TTY mode is not supported
+     */
+    public function setTty($tty)
+    {
+        if ('\\' === DIRECTORY_SEPARATOR && $tty) {
+            throw new RuntimeException('TTY mode is not supported on Windows platform.');
+        }
+        if ($tty) {
+            static $isTtySupported;
+
+            if (null === $isTtySupported) {
+                $isTtySupported = (bool) @proc_open('echo 1 >/dev/null', array(array('file', '/dev/tty', 'r'), array('file', '/dev/tty', 'w'), array('file', '/dev/tty', 'w')), $pipes);
+            }
+
+            if (!$isTtySupported) {
+                throw new RuntimeException('TTY mode requires /dev/tty to be read/writable.');
+            }
+        }
+
+        $this->tty = (bool) $tty;
+
+        return $this;
+    }
+
+    /**
+     * Checks if the TTY mode is enabled.
+     *
+     * @return bool true if the TTY mode is enabled, false otherwise
+     */
+    public function isTty()
+    {
+        return $this->tty;
+    }
+
+    /**
+     * Sets PTY mode.
+     *
+     * @param bool $bool
+     *
+     * @return self
+     */
+    public function setPty($bool)
+    {
+        $this->pty = (bool) $bool;
+
+        return $this;
+    }
+
+    /**
+     * Returns PTY state.
+     *
+     * @return bool
+     */
+    public function isPty()
+    {
+        return $this->pty;
+    }
+
+    /**
+     * Gets the working directory.
+     *
+     * @return string|null The current working directory or null on failure
+     */
+    public function getWorkingDirectory()
+    {
+        if (null === $this->cwd) {
+            // getcwd() will return false if any one of the parent directories does not have
+            // the readable or search mode set, even if the current directory does
+            return getcwd() ?: null;
+        }
+
+        return $this->cwd;
+    }
+
+    /**
+     * Sets the current working directory.
+     *
+     * @param string $cwd The new working directory
+     *
+     * @return self The current Process instance
+     */
+    public function setWorkingDirectory($cwd)
+    {
+        $this->cwd = $cwd;
+
+        return $this;
+    }
+
+    /**
+     * Gets the environment variables.
+     *
+     * @return array The current environment variables
+     */
+    public function getEnv()
+    {
+        return $this->env;
+    }
+
+    /**
+     * Sets the environment variables.
+     *
+     * Each environment variable value should be a string.
+     * If it is an array, the variable is ignored.
+     * If it is false or null, it will be removed when
+     * env vars are otherwise inherited.
+     *
+     * That happens in PHP when 'argv' is registered into
+     * the $_ENV array for instance.
+     *
+     * @param array $env The new environment variables
+     *
+     * @return self The current Process instance
+     */
+    public function setEnv(array $env)
+    {
+        // Process can not handle env values that are arrays
+        $env = array_filter($env, function ($value) {
+            return !is_array($value);
+        });
+
+        $this->env = $env;
+
+        return $this;
+    }
+
+    /**
+     * Gets the Process input.
+     *
+     * @return resource|string|\Iterator|null The Process input
+     */
+    public function getInput()
+    {
+        return $this->input;
+    }
+
+    /**
+     * Sets the input.
+     *
+     * This content will be passed to the underlying process standard input.
+     *
+     * @param string|int|float|bool|resource|\Traversable|null $input The content
+     *
+     * @return self The current Process instance
+     *
+     * @throws LogicException In case the process is running
+     */
+    public function setInput($input)
+    {
+        if ($this->isRunning()) {
+            throw new LogicException('Input can not be set while the process is running.');
+        }
+
+        $this->input = ProcessUtils::validateInput(__METHOD__, $input);
+
+        return $this;
+    }
+
+    /**
+     * Gets the options for proc_open.
+     *
+     * @return array The current options
+     *
+     * @deprecated since version 3.3, to be removed in 4.0.
+     */
+    public function getOptions()
+    {
+        @trigger_error(sprintf('The %s() method is deprecated since Symfony 3.3 and will be removed in 4.0.', __METHOD__), E_USER_DEPRECATED);
+
+        return $this->options;
+    }
+
+    /**
+     * Sets the options for proc_open.
+     *
+     * @param array $options The new options
+     *
+     * @return self The current Process instance
+     *
+     * @deprecated since version 3.3, to be removed in 4.0.
+     */
+    public function setOptions(array $options)
+    {
+        @trigger_error(sprintf('The %s() method is deprecated since Symfony 3.3 and will be removed in 4.0.', __METHOD__), E_USER_DEPRECATED);
+
+        $this->options = $options;
+
+        return $this;
+    }
+
+    /**
+     * Gets whether or not Windows compatibility is enabled.
+     *
+     * This is true by default.
+     *
+     * @return bool
+     *
+     * @deprecated since version 3.3, to be removed in 4.0. Enhanced Windows compatibility will always be enabled.
+     */
+    public function getEnhanceWindowsCompatibility()
+    {
+        @trigger_error(sprintf('The %s() method is deprecated since Symfony 3.3 and will be removed in 4.0. Enhanced Windows compatibility will always be enabled.', __METHOD__), E_USER_DEPRECATED);
+
+        return $this->enhanceWindowsCompatibility;
+    }
+
+    /**
+     * Sets whether or not Windows compatibility is enabled.
+     *
+     * @param bool $enhance
+     *
+     * @return self The current Process instance
+     *
+     * @deprecated since version 3.3, to be removed in 4.0. Enhanced Windows compatibility will always be enabled.
+     */
+    public function setEnhanceWindowsCompatibility($enhance)
+    {
+        @trigger_error(sprintf('The %s() method is deprecated since Symfony 3.3 and will be removed in 4.0. Enhanced Windows compatibility will always be enabled.', __METHOD__), E_USER_DEPRECATED);
+
+        $this->enhanceWindowsCompatibility = (bool) $enhance;
+
+        return $this;
+    }
+
+    /**
+     * Returns whether sigchild compatibility mode is activated or not.
+     *
+     * @return bool
+     *
+     * @deprecated since version 3.3, to be removed in 4.0. Sigchild compatibility will always be enabled.
+     */
+    public function getEnhanceSigchildCompatibility()
+    {
+        @trigger_error(sprintf('The %s() method is deprecated since Symfony 3.3 and will be removed in 4.0. Sigchild compatibility will always be enabled.', __METHOD__), E_USER_DEPRECATED);
+
+        return $this->enhanceSigchildCompatibility;
+    }
+
+    /**
+     * Activates sigchild compatibility mode.
+     *
+     * Sigchild compatibility mode is required to get the exit code and
+     * determine the success of a process when PHP has been compiled with
+     * the --enable-sigchild option
+     *
+     * @param bool $enhance
+     *
+     * @return self The current Process instance
+     *
+     * @deprecated since version 3.3, to be removed in 4.0.
+     */
+    public function setEnhanceSigchildCompatibility($enhance)
+    {
+        @trigger_error(sprintf('The %s() method is deprecated since Symfony 3.3 and will be removed in 4.0. Sigchild compatibility will always be enabled.', __METHOD__), E_USER_DEPRECATED);
+
+        $this->enhanceSigchildCompatibility = (bool) $enhance;
+
+        return $this;
+    }
+
+    /**
+     * Sets whether environment variables will be inherited or not.
+     *
+     * @param bool $inheritEnv
+     *
+     * @return self The current Process instance
+     */
+    public function inheritEnvironmentVariables($inheritEnv = true)
+    {
+        if (!$inheritEnv) {
+            @trigger_error('Not inheriting environment variables is deprecated since Symfony 3.3 and will always happen in 4.0. Set "Process::inheritEnvironmentVariables()" to true instead.', E_USER_DEPRECATED);
+        }
+
+        $this->inheritEnv = (bool) $inheritEnv;
+
+        return $this;
+    }
+
+    /**
+     * Returns whether environment variables will be inherited or not.
+     *
+     * @return bool
+     *
+     * @deprecated since version 3.3, to be removed in 4.0. Environment variables will always be inherited.
+     */
+    public function areEnvironmentVariablesInherited()
+    {
+        @trigger_error(sprintf('The %s() method is deprecated since Symfony 3.3 and will be removed in 4.0. Environment variables will always be inherited.', __METHOD__), E_USER_DEPRECATED);
+
+        return $this->inheritEnv;
+    }
+
+    /**
+     * Performs a check between the timeout definition and the time the process started.
+     *
+     * In case you run a background process (with the start method), you should
+     * trigger this method regularly to ensure the process timeout
+     *
+     * @throws ProcessTimedOutException In case the timeout was reached
+     */
+    public function checkTimeout()
+    {
+        if (self::STATUS_STARTED !== $this->status) {
+            return;
+        }
+
+        if (null !== $this->timeout && $this->timeout < microtime(true) - $this->starttime) {
+            $this->stop(0);
+
+            throw new ProcessTimedOutException($this, ProcessTimedOutException::TYPE_GENERAL);
+        }
+
+        if (null !== $this->idleTimeout && $this->idleTimeout < microtime(true) - $this->lastOutputTime) {
+            $this->stop(0);
+
+            throw new ProcessTimedOutException($this, ProcessTimedOutException::TYPE_IDLE);
+        }
+    }
+
+    /**
+     * Returns whether PTY is supported on the current operating system.
+     *
+     * @return bool
+     */
+    public static function isPtySupported()
+    {
+        static $result;
+
+        if (null !== $result) {
+            return $result;
+        }
+
+        if ('\\' === DIRECTORY_SEPARATOR) {
+            return $result = false;
+        }
+
+        return $result = (bool) @proc_open('echo 1 >/dev/null', array(array('pty'), array('pty'), array('pty')), $pipes);
+    }
+
+    /**
+     * Creates the descriptors needed by the proc_open.
+     *
+     * @return array
+     */
+    private function getDescriptors()
+    {
+        if ($this->input instanceof \Iterator) {
+            $this->input->rewind();
+        }
+        if ('\\' === DIRECTORY_SEPARATOR) {
+            $this->processPipes = new WindowsPipes($this->input, !$this->outputDisabled || $this->hasCallback);
+        } else {
+            $this->processPipes = new UnixPipes($this->isTty(), $this->isPty(), $this->input, !$this->outputDisabled || $this->hasCallback);
+        }
+
+        return $this->processPipes->getDescriptors();
+    }
+
+    /**
+     * Builds up the callback used by wait().
+     *
+     * The callbacks adds all occurred output to the specific buffer and calls
+     * the user callback (if present) with the received output.
+     *
+     * @param callable|null $callback The user defined PHP callback
+     *
+     * @return \Closure A PHP closure
+     */
+    protected function buildCallback(callable $callback = null)
+    {
+        if ($this->outputDisabled) {
+            return function ($type, $data) use ($callback) {
+                if (null !== $callback) {
+                    call_user_func($callback, $type, $data);
+                }
+            };
+        }
+
+        $out = self::OUT;
+
+        return function ($type, $data) use ($callback, $out) {
+            if ($out == $type) {
+                $this->addOutput($data);
+            } else {
+                $this->addErrorOutput($data);
+            }
+
+            if (null !== $callback) {
+                call_user_func($callback, $type, $data);
+            }
+        };
+    }
+
+    /**
+     * Updates the status of the process, reads pipes.
+     *
+     * @param bool $blocking Whether to use a blocking read call
+     */
+    protected function updateStatus($blocking)
+    {
+        if (self::STATUS_STARTED !== $this->status) {
+            return;
+        }
+
+        $this->processInformation = proc_get_status($this->process);
+        $running = $this->processInformation['running'];
+
+        $this->readPipes($running && $blocking, '\\' !== DIRECTORY_SEPARATOR || !$running);
+
+        if ($this->fallbackStatus && $this->enhanceSigchildCompatibility && $this->isSigchildEnabled()) {
+            $this->processInformation = $this->fallbackStatus + $this->processInformation;
+        }
+
+        if (!$running) {
+            $this->close();
+        }
+    }
+
+    /**
+     * Returns whether PHP has been compiled with the '--enable-sigchild' option or not.
+     *
+     * @return bool
+     */
+    protected function isSigchildEnabled()
+    {
+        if (null !== self::$sigchild) {
+            return self::$sigchild;
+        }
+
+        if (!function_exists('phpinfo') || defined('HHVM_VERSION')) {
+            return self::$sigchild = false;
+        }
+
+        ob_start();
+        phpinfo(INFO_GENERAL);
+
+        return self::$sigchild = false !== strpos(ob_get_clean(), '--enable-sigchild');
+    }
+
+    /**
+     * Reads pipes for the freshest output.
+     *
+     * @param string $caller   The name of the method that needs fresh outputs
+     * @param bool   $blocking Whether to use blocking calls or not
+     *
+     * @throws LogicException in case output has been disabled or process is not started
+     */
+    private function readPipesForOutput($caller, $blocking = false)
+    {
+        if ($this->outputDisabled) {
+            throw new LogicException('Output has been disabled.');
+        }
+
+        $this->requireProcessIsStarted($caller);
+
+        $this->updateStatus($blocking);
+    }
+
+    /**
+     * Validates and returns the filtered timeout.
+     *
+     * @param int|float|null $timeout
+     *
+     * @return float|null
+     *
+     * @throws InvalidArgumentException if the given timeout is a negative number
+     */
+    private function validateTimeout($timeout)
+    {
+        $timeout = (float) $timeout;
+
+        if (0.0 === $timeout) {
+            $timeout = null;
+        } elseif ($timeout < 0) {
+            throw new InvalidArgumentException('The timeout value must be a valid positive integer or float number.');
+        }
+
+        return $timeout;
+    }
+
+    /**
+     * Reads pipes, executes callback.
+     *
+     * @param bool $blocking Whether to use blocking calls or not
+     * @param bool $close    Whether to close file handles or not
+     */
+    private function readPipes($blocking, $close)
+    {
+        $result = $this->processPipes->readAndWrite($blocking, $close);
+
+        $callback = $this->callback;
+        foreach ($result as $type => $data) {
+            if (3 !== $type) {
+                $callback(self::STDOUT === $type ? self::OUT : self::ERR, $data);
+            } elseif (!isset($this->fallbackStatus['signaled'])) {
+                $this->fallbackStatus['exitcode'] = (int) $data;
+            }
+        }
+    }
+
+    /**
+     * Closes process resource, closes file handles, sets the exitcode.
+     *
+     * @return int The exitcode
+     */
+    private function close()
+    {
+        $this->processPipes->close();
+        if (is_resource($this->process)) {
+            proc_close($this->process);
+        }
+        $this->exitcode = $this->processInformation['exitcode'];
+        $this->status = self::STATUS_TERMINATED;
+
+        if (-1 === $this->exitcode) {
+            if ($this->processInformation['signaled'] && 0 < $this->processInformation['termsig']) {
+                // if process has been signaled, no exitcode but a valid termsig, apply Unix convention
+                $this->exitcode = 128 + $this->processInformation['termsig'];
+            } elseif ($this->enhanceSigchildCompatibility && $this->isSigchildEnabled()) {
+                $this->processInformation['signaled'] = true;
+                $this->processInformation['termsig'] = -1;
+            }
+        }
+
+        // Free memory from self-reference callback created by buildCallback
+        // Doing so in other contexts like __destruct or by garbage collector is ineffective
+        // Now pipes are closed, so the callback is no longer necessary
+        $this->callback = null;
+
+        return $this->exitcode;
+    }
+
+    /**
+     * Resets data related to the latest run of the process.
+     */
+    private function resetProcessData()
+    {
+        $this->starttime = null;
+        $this->callback = null;
+        $this->exitcode = null;
+        $this->fallbackStatus = array();
+        $this->processInformation = null;
+        $this->stdout = fopen('php://temp/maxmemory:'.(1024 * 1024), 'wb+');
+        $this->stderr = fopen('php://temp/maxmemory:'.(1024 * 1024), 'wb+');
+        $this->process = null;
+        $this->latestSignal = null;
+        $this->status = self::STATUS_READY;
+        $this->incrementalOutputOffset = 0;
+        $this->incrementalErrorOutputOffset = 0;
+    }
+
+    /**
+     * Sends a POSIX signal to the process.
+     *
+     * @param int  $signal         A valid POSIX signal (see http://www.php.net/manual/en/pcntl.constants.php)
+     * @param bool $throwException Whether to throw exception in case signal failed
+     *
+     * @return bool True if the signal was sent successfully, false otherwise
+     *
+     * @throws LogicException   In case the process is not running
+     * @throws RuntimeException In case --enable-sigchild is activated and the process can't be killed
+     * @throws RuntimeException In case of failure
+     */
+    private function doSignal($signal, $throwException)
+    {
+        if (null === $pid = $this->getPid()) {
+            if ($throwException) {
+                throw new LogicException('Can not send signal on a non running process.');
+            }
+
+            return false;
+        }
+
+        if ('\\' === DIRECTORY_SEPARATOR) {
+            exec(sprintf('taskkill /F /T /PID %d 2>&1', $pid), $output, $exitCode);
+            if ($exitCode && $this->isRunning()) {
+                if ($throwException) {
+                    throw new RuntimeException(sprintf('Unable to kill the process (%s).', implode(' ', $output)));
+                }
+
+                return false;
+            }
+        } else {
+            if (!$this->enhanceSigchildCompatibility || !$this->isSigchildEnabled()) {
+                $ok = @proc_terminate($this->process, $signal);
+            } elseif (function_exists('posix_kill')) {
+                $ok = @posix_kill($pid, $signal);
+            } elseif ($ok = proc_open(sprintf('kill -%d %d', $signal, $pid), array(2 => array('pipe', 'w')), $pipes)) {
+                $ok = false === fgets($pipes[2]);
+            }
+            if (!$ok) {
+                if ($throwException) {
+                    throw new RuntimeException(sprintf('Error while sending signal `%s`.', $signal));
+                }
+
+                return false;
+            }
+        }
+
+        $this->latestSignal = (int) $signal;
+        $this->fallbackStatus['signaled'] = true;
+        $this->fallbackStatus['exitcode'] = -1;
+        $this->fallbackStatus['termsig'] = $this->latestSignal;
+
+        return true;
+    }
+
+    private function prepareWindowsCommandLine($cmd, array &$env)
+    {
+        $uid = uniqid('', true);
+        $varCount = 0;
+        $varCache = array();
+        $cmd = preg_replace_callback(
+            '/"(?:(
+                [^"%!^]*+
+                (?:
+                    (?: !LF! | "(?:\^[%!^])?+" )
+                    [^"%!^]*+
+                )++
+            ) | [^"]*+ )"/x',
+            function ($m) use (&$env, &$varCache, &$varCount, $uid) {
+                if (!isset($m[1])) {
+                    return $m[0];
+                }
+                if (isset($varCache[$m[0]])) {
+                    return $varCache[$m[0]];
+                }
+                if (false !== strpos($value = $m[1], "\0")) {
+                    $value = str_replace("\0", '?', $value);
+                }
+                if (false === strpbrk($value, "\"%!\n")) {
+                    return '"'.$value.'"';
+                }
+
+                $value = str_replace(array('!LF!', '"^!"', '"^%"', '"^^"', '""'), array("\n", '!', '%', '^', '"'), $value);
+                $value = '"'.preg_replace('/(\\\\*)"/', '$1$1\\"', $value).'"';
+                $var = $uid.++$varCount;
+
+                $env[$var] = $value;
+
+                return $varCache[$m[0]] = '!'.$var.'!';
+            },
+            $cmd
+        );
+
+        $cmd = 'cmd /V:ON /E:ON /D /C ('.str_replace("\n", ' ', $cmd).')';
+        foreach ($this->processPipes->getFiles() as $offset => $filename) {
+            $cmd .= ' '.$offset.'>"'.$filename.'"';
+        }
+
+        return $cmd;
+    }
+
+    /**
+     * Ensures the process is running or terminated, throws a LogicException if the process has a not started.
+     *
+     * @param string $functionName The function name that was called
+     *
+     * @throws LogicException if the process has not run
+     */
+    private function requireProcessIsStarted($functionName)
+    {
+        if (!$this->isStarted()) {
+            throw new LogicException(sprintf('Process must be started before calling %s.', $functionName));
+        }
+    }
+
+    /**
+     * Ensures the process is terminated, throws a LogicException if the process has a status different than `terminated`.
+     *
+     * @param string $functionName The function name that was called
+     *
+     * @throws LogicException if the process is not yet terminated
+     */
+    private function requireProcessIsTerminated($functionName)
+    {
+        if (!$this->isTerminated()) {
+            throw new LogicException(sprintf('Process must be terminated before calling %s.', $functionName));
+        }
+    }
+
+    /**
+     * Escapes a string to be used as a shell argument.
+     *
+     * @param string $argument The argument that will be escaped
+     *
+     * @return string The escaped argument
+     */
+    private function escapeArgument($argument)
+    {
+        if ('\\' !== DIRECTORY_SEPARATOR) {
+            return "'".str_replace("'", "'\\''", $argument)."'";
+        }
+        if ('' === $argument = (string) $argument) {
+            return '""';
+        }
+        if (false !== strpos($argument, "\0")) {
+            $argument = str_replace("\0", '?', $argument);
+        }
+        if (!preg_match('/[\/()%!^"<>&|\s]/', $argument)) {
+            return $argument;
+        }
+        $argument = preg_replace('/(\\\\+)$/', '$1$1', $argument);
+
+        return '"'.str_replace(array('"', '^', '%', '!', "\n"), array('""', '"^^"', '"^%"', '"^!"', '!LF!'), $argument).'"';
+    }
+
+    private function getDefaultEnv()
+    {
+        $env = array();
+
+        foreach ($_SERVER as $k => $v) {
+            if (is_string($v) && false !== $v = getenv($k)) {
+                $env[$k] = $v;
+            }
+        }
+
+        foreach ($_ENV as $k => $v) {
+            if (is_string($v)) {
+                $env[$k] = $v;
+            }
+        }
+
+        return $env;
+    }
+}