<?php
/*
*     FileName                     :     cache.inc.php
*     Link                             :     [url]http://blog.csdn.net/dxflingxing/[/url]
*     Author                             :     dxflingxing
*     Date                             :     2006-5-9
*     Last Modified                 :     2006-5-16
*     Version                             :     1.0.1
*     Description                     :     Cache a page in file formart
*     Notice                             :     Make sure you cache file dir can be readed and wrote
*
*     Thanks to                     :     小邪,barryonline(寒)
************************************************************
*
*     Usage                             :
*             # Cache active time half an hour
*             # This Can Auotmatic make some none exist dirs
*             # Or you can use an cache file in curent dir
*             # The Usage Such as 
*             # $cache     = new cache(string cache_name,int seconds);
*
*             require ('cache.inc.php');
*             $cache     = new cache('dir1/dir2/cache_name.htm',60*30);     
*
*             $cache->start();
*
*             # Your Page Contents With print
*             phpinfo();
*
*             $cache->_end();
*
*/
    
class cache {
     var $_file;
     var $cache_time;
    
     function cache($_file='_index.htm',$cache_time=1) {
             $this->_file             = $_file;
             $this->cache_time     = $cache_time;
     }
    
     /*
     * Start cache method without Return
     */
     function start() {
         
             if($this->cache_is_active()) {
                 include($this->_file);
                 exit;
                 }
             ob_start();
     }
    
     /*
     * End of cache method without Return
     */
     function _end() {
             $this->make_cache();
             ob_end_flush();
     }
    
     /*
     * Check if cache file is actived
     * Return true/false
     */
     function cache_is_active() {
             if ($this->cache_is_exist()) {
                 if (time() - $this->lastModified() < $this->cache_time)
                     Return true;
                 else {
                     Return false;
                 } 
             }
             else {
                 Return false;
             } 
     }
    
     /*
     * Create cache file
     * Return true/false
     */
     function make_cache() {
             $content     = $this->get_cache_content();
             if($this->write_file($content)) {
                 Return true;
             }
             else {
                 Return false;
             }
     }
    
     /*
     * Check if cache file is exists
     * Return true/false
     */
     function cache_is_exist() {
             if(file_exists($this->_file)) {
                 Return true;
             }
             else {
                 Return false;
             }
     }
    
     /*
     * Return last Modified time in bollin formart
     * Usage: $lastmodified = $this->lastModified();
     */
     function lastModified() {
             Return @filemtime($this->_file);
     }
    
     /*
     * Return Content of Page
     * Usage: $content = $this->get_cache_content();
     */
     function get_cache_content() {
             $contents = ob_get_contents();
//             Return '<!--'.date('Y-m-d H:i:s').'-->'.$contents;
             Return $contents;
     }
    
     /*Write content to $this->_file 
     * Return true/false
     * Usage: $this->write_file($content);
     **/
     function write_file($content,$mode='w+')
     {
             $this->mk_dir($this->_file);
             if (!$fp = @fopen($this->_file,$mode)) {
                 $this->report_Error($this->_file." 目录或者文件属性无法写入.");
                 Return false;
             } else{
                 @fwrite($fp,$content);
                 @fclose($fp);
                 @umask($oldmask);
                 Return true;
             }
     }
    
     /*
     * Make given dir included in $this->_file
     * Without Return
     * Usage: $this->mk_dir();
     */
     function mk_dir()
     {     //$this->_file     = str_replace('','/');
             $dir     = @explode("/", $this->_file);
             $num     = @count($dir)-1;
             $tmp     = './';
             for($i=0; $i<$num; $i++){
                 $tmp     .= $dir[$i];
                 if(!file_exists($tmp)){
                     @mkdir($tmp);
                     @chmod($tmp, 0777);
                 }
                 $tmp     .= '/';
             }
     }
    
     /*
     * Unlink an exists cache
     * Return true/false
     * Usage: $this->clear_cache();
     */
     function clear_cache() {
             if (!@unlink($this->_file)) {
                 $this->report_Error('Unable to remove cache');
                 Return false;
             }
             else {
                 Return true;
             }
     }
    
     /*
     * Report Error Messages
     * Usage: $this->report_Error($message);
     */
     function report_Error($message=NULL) {
             if($message!=NULL) {
                 trigger_error($message);     
             }
     }
}
?>