command.php

来自「视频监控网络部分的协议ddns,的模块的实现代码,请大家大胆指正.」· PHP 代码 · 共 546 行 · 第 1/2 页

<?php
// {{{ license

// +----------------------------------------------------------------------+
// | PHP Version 4.0                                                      |
// +----------------------------------------------------------------------+
// | Copyright (c) 1997-2003 The PHP Group                                |
// +----------------------------------------------------------------------+
// | This source file is subject to version 2.02 of the PHP license,      |
// | that is bundled with this package in the file LICENSE, and is        |
// | available at through the world-wide-web at                           |
// | http://www.php.net/license/2_02.txt.                                 |
// | If you did not receive a copy of the PHP license and are unable to   |
// | obtain it through the world-wide-web, please send a note to          |
// | [e-mail] so we can mail you a copy immediately.               |
// +----------------------------------------------------------------------+
// | Author: Anders Johannsen <[e-mail]>                      |
// | Author: Dan Allen <[e-mail]>
// +----------------------------------------------------------------------+

// $Id: Command.php,v 1.4 2004/03/02 05:21:41 dallen Exp $

// }}}
// {{{ includes

require_once 'PEAR.php';
require_once 'System.php';

// }}}
// {{{ constants

define('SYSTEM_COMMAND_OK',                 1);
define('SYSTEM_COMMAND_ERROR',             -1);
define('SYSTEM_COMMAND_NO_SHELL',          -2);
define('SYSTEM_COMMAND_INVALID_SHELL',     -3);
define('SYSTEM_COMMAND_TMPDIR_ERROR',      -4);
define('SYSTEM_COMMAND_INVALID_OPERATOR',  -5);
define('SYSTEM_COMMAND_INVALID_COMMAND',   -6);
define('SYSTEM_COMMAND_OPERATOR_PLACEMENT',-7);
define('SYSTEM_COMMAND_COMMAND_PLACEMENT', -8);
define('SYSTEM_COMMAND_NOHUP_MISSING',     -9);
define('SYSTEM_COMMAND_NO_OUTPUT',        -10);
define('SYSTEM_COMMAND_STDERR',           -11);

// }}}

// {{{ class System_Command

/**
 * The System_Command:: class implements an abstraction for various ways 
 * of executing commands (directly using the backtick operator,
 * as a background task after the script has terminated using
 * register_shutdown_function() or as a detached process using nohup).
 *
 * @author  Anders Johannsen <[e-mail]>
 * @author  Dan Allen <[e-mail]>
 * @version $Revision: 1.4 $
 */

// }}}
class System_Command extends PEAR {
    // {{{ properties

    /**
     * Array of settings used when creating the shell command
     *
     * @var array
     * @access private
     */
    var $options = array();

    /**
     * Array of available shells to use to execute the command
     *
     * @var array
     * @access private
     */
    var $shells = array();

    /**
     * Array of available control operators used between commands
     *
     * @var array
     * @access private
     */
    var $controlOperators = array();

    /**
     * The system command to be executed
     *
     * @var string
     * @access private
     */
    var $systemCommand = null;

    /**
     * Previously added part to the command string
     *
     * @var string
     * @access private
     */
    var $previousElement = null;

    /**
     * Directory for writing stderr output
     *
     * @var string
     * @access private
     */
    var $tmpDir = null;

    /**
     * To allow the pear error object to accumulate when building
     * the command, we use the command status to keep track when
     * a pear error is raised
     *
     * @var int
     * @access private
     */
    var $commandStatus = 0;
        
    // }}}
    // {{{ constructor

    /**
     * Class constructor
     * 
     * Defines all necessary constants and sets defaults
     * 
     * @access public
     */
    function System_Command($in_shell = null)
    {
        parent::PEAR();

        // Defining constants
        $this->options = array(
            'SEQUENCE'   => true,
            'SHUTDOWN'   => false,
            'SHELL'      => $this->which($in_shell),
            'OUTPUT'     => true,
            'NOHUP'      => false,
            'BACKGROUND' => false,
        );

        // prepare the available control operators
        $this->controlOperators = array(
            'PIPE'  => '|',
            'AND'   => '&&',
            'OR'    => '||',
            'GROUP' => ';',
            'LFIFO' => '<',
            'RFIFO' => '>',
        );
                
        // List of allowed/available shells
        $this->shells = array(
            'sh',
            'bash',
            'zsh',
            'tcsh',
            'csh',
            'ash',
            'sash',
            'esh',
            'ksh'
        );
                                   
        // Find the first available shell
        if (empty($this->options['SHELL'])) {
            foreach ($this->shells as $shell) {
                if ($this->options['SHELL'] = $this->which($shell)) {
                    break;
                }
            }

            // see if we still have no shell
            if (empty($this->options['SHELL'])) {
                $this = PEAR::raiseError(null, SYSTEM_COMMAND_NO_SHELL, null, E_USER_WARNING, null, 'System_Command_Error', true);
                return;
            }
        }

        // Caputre a temporary directory for capturing stderr from commands
        $this->tmpdir = System::tmpdir();
        if (!System::mkDir("-p {$this->tmpdir}")) {
            $this = PEAR::raiseError(null, SYSTEM_COMMAND_TMPDIR_ERROR, null, E_USER_WARNING, null, 'System_Command_Error', true);
            return;
        }
    }
        
    // }}}
    // {{{ setOption()

    /**
     * Sets any option
     * 
     * The options are currently:
     * SEQUENCE : Allow a sequence command or not (right now this is always on)
     * SHUTDOWN : Execute commands via a shutdown function 
     * SHELL    : Path to shell
     * OUTPUT   : Output stdout from process
     * NOHUP    : Use nohup to detach process
     * BACKGROUND : Run as a background process with &
     *
     * @param $in_option is a constant, which corresponds to the
     *                option that should be changed
     * @param $in_setting is the value of the option currently
     *                 being toggled.
     * @access public
     * @return bool true if succes, else false
     */
    function setOption($in_option, $in_setting)
    {
        $option = strtoupper($in_option);

        if (empty($this->options[$option])) {
            PEAR::raiseError(null, SYSTEM_COMMAND_ERROR, null, E_USER_NOTICE, null, 'System_Command_Error', true);
            return false;
        }
                
        switch ($option) {
            case 'OUTPUT':
            case 'SHUTDOWN':
            case 'SEQUENCE':
            case 'BACKGROUND':
                $this->options[$option] = !empty($in_setting);
                return true;
            break;
                
            case 'SHELL':
                if (($shell = $this->which($in_setting)) !== false) {
                    $this->options[$option] = $shell;
                    return true;
                } 
                else {
                    PEAR::raiseError(null, SYSTEM_COMMAND_NO_SHELL, null, E_USER_NOTICE, $in_setting, 'System_Command_Error', true);
                    return false;
                }
            break;
                        
            case 'NOHUP':
                if (empty($in_setting)) {
                    $this->options[$option] = false;
                } 
                else if ($location = $this->which('nohup')) {
                    $this->options[$option] = $location;
                } 
                else {
                    PEAR::raiseError(null, SYSTEM_COMMAND_NOHUP_MISSING, null, E_USER_NOTICE, null, 'System_Command_Error', true);
                    return false;
                }
            break;
        }
    }
    
    // }}}
    // {{{ pushCommand()

    /**
     * Used to push a command onto the running command to be executed
     *
     * @param  string $in_command binary to be run
     * @param  string $in_argument either an option or argument value, to be handled appropriately
     * @param  string $in_argument
     * @param  ...
     *
     * @access public
     * @return boolean true on success {or System_Command_Error Exception}
     */
    function pushCommand($in_command)
    {
        if (!is_null($this->previousElement) && !in_array($this->previousElement, $this->controlOperators)) {