/common/libraries/plugin/phpfreechat/src/containers/file.class.php

<?php

/**
 * file.class.php
 *
 * Copyright ??? 2006 Stephane Gully <stephane.gully@gmail.com>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful, 
 * but WITHOUT ANY WARRANTY; without even the implied warranty of 
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details. 
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, 51 Franklin St, Fifth Floor,
 * Boston, MA  02110-1301  USA
 */



require_once dirname(__FILE__) . "/../pfccontainerinterface.class.php";



/**
 * pfcContainer_File is a concret container which stock data into files
 *
 * @author Stephane Gully <stephane.gully@gmail.com>
 */

class pfcContainer_File extends pfcContainerInterface

{

    var $_users = array("nickid" => array(), "timestamp" => array());

    var $_meta = array();



    function __construct()

    {

        pfcContainerInterface :: __construct();

    }



    function loadPaths(&$c)

    {

        if (! isset($c->container_cfg_chat_dir) || $c->container_cfg_chat_dir == '')

            $c->container_cfg_chat_dir = $c->data_private_path . "/chat";

        if (! isset($c->container_cfg_server_dir) || $c->container_cfg_server_dir == '')

            $c->container_cfg_server_dir = $c->container_cfg_chat_dir . "/s_" . $c->serverid;

    }



    function getDefaultConfig()

    {

        $cfg = pfcContainerInterface :: getDefaultConfig();

        $cfg["chat_dir"] = ''; // will be generated from the other parameters into the init step
        $cfg["server_dir"] = ''; // will be generated from the other parameters into the init step
        return $cfg;

    }



    function init(&$c)

    {

        $errors = pfcContainerInterface :: init($c);

        

        // generate the container parameters from other config parameters
        $this->loadPaths($c);

        

        $errors = array_merge($errors, @test_writable_dir($c->container_cfg_chat_dir, "container_cfg_chat_dir"));

        $errors = array_merge($errors, @test_writable_dir($c->container_cfg_server_dir, "container_cfg_chat_dir/serverid"));

        

        // test the filemtime php function because it doesn't work on special filesystem
        // example : NFS, VZFS
        $filename = $c->data_private_path . '/filemtime.test';

        $timetowait = 2;

        if (is_writable(dirname($filename)))

        {

            file_put_contents($filename, 'some-data1-' . time());

            clearstatcache();

            $time1 = filemtime($filename);

            sleep($timetowait);

            file_put_contents($filename, 'some-data2-' . time());

            clearstatcache();

            $time2 = filemtime($filename);

            unlink($filename);

            if ($time2 - $time1 != $timetowait)

                $errors[] = "filemtime php fuction is not usable on your filesystem. Please do not use the 'file' container (try the 'mysql' container) or swith to another filesystem type.";

        }

        

        // test the LOCK_EX feature because it doesn't work on special filsystem like NFS
        $filename = $c->data_private_path . '/filemtime.test';

        if (is_writable(dirname($filename)))

        {

            $data1 = time();

            //file_put_contents($filename, $data1, LOCK_EX);
            file_put_contents($filename, $data1);

            $data2 = file_get_contents($filename);

            if ($data1 != $data2)

            {

            }

        

     //$errors[] = "LOCK_EX feature is not usable on your filesystem. Please do not use the 'file' container (try the 'mysql' container) or swith to another filesystem type.";
        }

        

        return $errors;

    }



    function setMeta($group, $subgroup, $leaf, $leafvalue = NULL)

    {

        $c = & pfcGlobalConfig :: Instance();

        

        // create directories
        $dir_base = $c->container_cfg_server_dir;

        $dir = $dir_base . '/' . $group . '/' . $subgroup;

        if (! is_dir($dir))

            mkdir_r($dir);

        

     // create or replace metadata file
        $leaffilename = $dir . "/" . $leaf;

        $leafexists = file_exists($leaffilename);

        if ($leafvalue == NULL)

        {

            touch($leaffilename);

        }

        else

        {

            //file_put_contents($leaffilename, $leafvalue, LOCK_EX);
            file_put_contents($leaffilename, $leafvalue);

        }

        

        // store the value in the memory cache
        //@todo
        //    $this->_meta[$enc_type][$enc_subtype][$enc_key] = $value;
        



        if ($leafexists)

            return 1; // value overwritten
        else

            return 0; // value created
    }



    function getMeta($group, $subgroup = null, $leaf = null, $withleafvalue = false)

    {

        $c = & pfcGlobalConfig :: Instance();

        

        // read data from metadata file
        $ret = array();

        $ret["timestamp"] = array();

        $ret["value"] = array();

        $dir_base = $c->container_cfg_server_dir;

        

        $dir = $dir_base . '/' . $group;

        if ($subgroup == NULL)

        {

            if (is_dir($dir))

            {

                $dh = opendir($dir);

                while (false !== ($file = readdir($dh)))

                {

                    if ($file == "." || $file == "..")

                        continue; // skip . and .. generic files
                    $ret["timestamp"][] = filemtime($dir . '/' . $file);

                    $ret["value"][] = $file;

                }

                closedir($dh);

            }

            return $ret;

        }

        

        $dir .= '/' . $subgroup;

        

        if ($leaf == NULL)

        {

            if (is_dir($dir))

            {

                $dh = opendir($dir);

                while (false !== ($file = readdir($dh)))

                {

                    if ($file == "." || $file == "..")

                        continue; // skip . and .. generic files
                    $ret["timestamp"][] = filemtime($dir . '/' . $file);

                    $ret["value"][] = $file;

                }

                closedir($dh);

            }

            

            return $ret;

        }

        

        $leaffilename = $dir . "/" . $leaf;

        

        if (! file_exists($leaffilename))

            return $ret;

        if ($withleafvalue)

            $ret["value"][] = file_get_contents_flock($leaffilename);

        else

            $ret["value"][] = NULL;

        $ret["timestamp"][] = filemtime($leaffilename);

        

        return $ret;

    }



    function incMeta($group, $subgroup, $leaf)

    {

        $c = & pfcGlobalConfig :: Instance();

        

        // create directories
        $dir_base = $c->container_cfg_server_dir;

        $dir = $dir_base . '/' . $group . '/' . $subgroup;

        if (! is_dir($dir))

            mkdir_r($dir);

        

     // create or replace metadata file
        $leaffilename = $dir . "/" . $leaf;

        

        // create return array
        $ret = array();

        $ret["timestamp"] = array();

        $ret["value"] = array();

        

        // read and increment data from metadata file
        clearstatcache();

        if (file_exists($leaffilename))

        {

            $fh = fopen($leaffilename, 'r+');

            for($i = 0; $i < 10; $i ++) // Try 10 times until an exclusive lock can be obtained
            {

                //if (flock($fh, LOCK_EX))
                {

                    $leafvalue = chop(fread($fh, filesize($leaffilename)));

                    $leafvalue ++;

                    rewind($fh);

                    fwrite($fh, $leafvalue);

                    fflush($fh);

                    ftruncate($fh, ftell($fh));

                    flock($fh, LOCK_UN);

                    break;

                }

                // If flock is working properly, this will never be reached
                $delay = rand(0, pow(2, ($i + 1)) - 1) * 5000; // Exponential backoff
                usleep($delay);

            }

            fclose($fh);

        }

        else

        {

            $leafvalue = "1";

            //file_put_contents($leaffilename, $leafvalue, LOCK_EX);
            file_put_contents($leaffilename, $leafvalue);

        }

        

        $ret["value"][] = $leafvalue;

        $ret["timestamp"][] = filemtime($leaffilename);

        

        return $ret;

    }



    function rmMeta($group, $subgroup = null, $leaf = null)

    {

        $c = & pfcGlobalConfig :: Instance();

        

        $dir = $c->container_cfg_server_dir;

        

        if ($group == NULL)

        {

            rm_r($dir);

            return true;

        }

        

        $dir .= '/' . $group;

        

        if ($subgroup == NULL)

        {

            rm_r($dir);

            return true;

        }

        

        $dir .= '/' . $subgroup;

        

        if ($leaf == NULL)

        {

            rm_r($dir);

            return true;

        }

        

        $leaffilename = $dir . '/' . $leaf;

        if (! file_exists($leaffilename))

            return false;

        unlink($leaffilename);

        

        // check that the directory is empty or not
        // remove it if it doesn't contains anything
        $dh = opendir($dir);

        readdir($dh);

        readdir($dh); // skip . and .. directories
        $isnotempty = readdir($dh);

        closedir($dh);

        if ($isnotempty === false)

            rmdir($dir);

        

        return true;

    }



    /**
     * Used to encode UTF8 strings to ASCII filenames
     */

    function encode($str)

    {

        return urlencode($str);

    }



    /**
     * Used to decode ASCII filenames to UTF8 strings
     */

    function decode($str)

    {

        return urldecode($str);

    }

}

?>