}

//Key-Value型文件存储
class fileCache{
private $_file_header_size = 14;
private $_file_index_name;
private $_file_data_name;
private $_file_index;//索引文件句柄
private $_file_data;//数据文件句柄
private $_node_struct;//索引结点结构体
private $_inx_node_size = 36;//索引结点大小

public function __construct($file_index="filecache_index.dat",$file_data="filecache_data.dat"){
$this->_node_struct = array(
'next'=>array(1,'V'),'prev'=>array(1,'data_offset'=>array(1,//数据存储起始位置
'data_size'=>array(1,//数据长度
'ref_count'=>array(1,//引用此处，模仿PHP的引用计数销毁模式
'key'=>array(16,'H*'),//存储KEY
);

 $this->_file_index_name = $file_index; 
 $this->_file_data_name = $file_data; 

 if(!file_exists($this->_file_index_name)){ 
    $this->_create_index(); 
 }else{ 
    $this->_file_index = fopen($this->_file_index_name,"rb+"); 
 } 

 if(!file_exists($this->_file_data_name)){ 
    $this->_create_data(); 
 }else{ 
    $this->_file_data = fopen($this->_file_data_name,"rb+");//二进制存储需要使用b 
 } 

}

//创建索引文件
private function _create_index(){
$this->_file_index = fopen($this->_file_index_name,"wb+");//二进制存储需要使用b
if(!$this->_file_index)
throw new fileCacheException("Could't open index file:".$this->_file_index_name);

 $this->_index_puts(0,'<'.'?php exit()?'.'>');//定位<a href="/tag/wenjian/" target="_blank" class="keywords">文件</a>流至起始位置0,放置<a href="/tag/PHP/" target="_blank" class="keywords">PHP</a><a href="/tag/biaoji/" target="_blank" class="keywords">标记</a>防止下载 
 $this->_index_puts($this->_file_header_size,pack("V1",0)); 

}

//创建存储文件
private function _create_data(){
$this->_file_data = fopen($this->_file_data_name,"wb+");//二进制存储需要使用b
if(!$this->_file_index)
throw new fileCacheException("Could't open index file:".$this->_file_data_name);

 $this->_data_puts(0,放置<a href="/tag/PHP/" target="_blank" class="keywords">PHP</a><a href="/tag/biaoji/" target="_blank" class="keywords">标记</a>防止下载 

}

private function _index_puts($offset,$data,$length=false){
fseek($this->_file_index,$offset);

 if($length) 
 fputs($this->_file_index,$length); 
 else 
 fputs($this->_file_index,$data); 

}

private function _data_puts($offset,$length=false){
fseek($this->_file_data,$offset);
if($length)
fputs($this->_file_data,$length);
else
fputs($this->_file_data,$data);
}

/**

• 文件锁
• @param $is_block 是否独占、阻塞锁
  */
  private function _lock($file_res,$is_block=true){
  flock($file_res,$is_block ? LOCK_EX : LOCK_EX|LOCK_NB);
  }

private function _unlock($file_res){
flock($file_res,LOCK_UN);
}

public function add($key,$value){
$key = md5($key);
$value = serialize($value);
$this->_lock($this->_file_index,true);
$this->_lock($this->_file_data,true);

 fseek($this->_file_index,$this->_file_header_size); 

 list(,$index_count) = unpack('V1',fread($this->_file_index,4)); 

 $data_size = filesize($this->_file_data_name); 

 fseek($this->_file_data,$data_size); 

 $value_size = strlen($value); 

 $this->_data_puts(filesize($this->_file_data_name),$value); 

 $node_data =  
 pack("V1V1V1V1V1H32",($index_count==0) ? 0 : $index_count*$this->_inx_node_size,filesize($this->_file_data_name),strlen($value),$key); 

 $index_count++; 

 $this->_index_puts($this->_file_header_size,$index_count,4); 

 $this->_index_puts($this->get_new_node_pos($index_count),$node_data); 

 $this->_unlock($this->_file_data); 
 $this->_unlock($this->_file_index); 

}

public function get_new_node_pos($index_count){
return $this->_file_header_size + 4 + $this->_inx_node_size * ($index_count-1);
}

public function get_node($key){
$key = md5($key);
fseek($this->_file_index,$this->_file_header_size);
$index_count = fread($this->_file_index,4);

 if($index_count>0) { 
    for ($i=0; $i < $index_count ; $i++) {  
      fseek($this->_file_index,$this->_file_header_size + 4 + $this->_inx_node_size * $i); 
      $data = fread($this->_file_index,$this->_inx_node_size); 
      $node = unpack("V1next/V1prev/V1data_offset/V1data_size/V1ref_count/H32key",$data); 

      if($key == $node['key']){ 
         return $node; 
      } 
    } 
 }else{ 
    return null; 
 } 

}

public function get_data($offset,$length){
fseek($this->_file_data,$offset);
return unserialize(fread($this->_file_data,$length));
}
}

//使用方法
$cache = new fileCache();
$cache->add('abcdefg','testabc');
$data = $cache->get_node('abcdefg');
print_r($data);
echo $cache->get_data($data['data_offset'],$data['data_size']);

$logoUT = array(
'COMMAND'=>array('a30','logoUT'),'GOOD BYE')
);

$LOGIN_SUCCESS = array(
'COMMAND'=>array('a30','LOGIN_SUCCESS'),'DATA'=>array('V1',1)
);

$logoUT_SUCCESS = array(
'COMMAND'=>array('a30',time())
);