PHP+memcache实现消息队列案例分享

        /**
    * Memcache 消息队列类
    */ 
    class QMC { 
    const PREFIX = 'ASDFASDFFWQKE'; 
    /**
    * 初始化mc
    * @staticvar string $mc
    * @return Memcache
    */ 
    static private function mc_init() { 
    static $mc = null; 
    if (is_null($mc)) { 
    $mc = new Memcache; 
    $mc->connect('127.0.0.1', 11211); 
    } 
    return $mc; 
    } 
    /**
    * mc 计数器,增加计数并返回新的计数
    * @param string $key   计数器
    * @param int $offset   计数增量,可为负数.0为不改变计数
    * @param int $time     时间
    * @return int/false    失败是返回false,成功时返回更新计数器后的计数
    */ 
    static public function set_counter( $key, $offset, $time=0 ){ 
    $mc = self::mc_init(); 
    $val = $mc->get($key); 
    if( !is_numeric($val) || $val < 0 ){ 
    $ret = $mc->set( $key, 0, $time ); 
    if( !$ret ) return false; 
    $val = 0; 
    } 
    $offset = intval( $offset ); 
    if( $offset > 0 ){ 
    return $mc->increment( $key, $offset ); 
    }elseif( $offset < 0 ){ 
    return $mc->decrement( $key, -$offset ); 
    } 
    return $val; 
    } 
    /**
    * 写入队列
    * @param string $key
    * @param mixed $value
    * @return bool
    */ 
    static public function input( $key, $value ){ 
    $mc = self::mc_init(); 
    $w_key = self::PREFIX.$key.'W'; 
    $v_key = self::PREFIX.$key.self::set_counter($w_key, 1); 
    return $mc->set( $v_key, $value ); 
    } 
    /**
    * 读取队列里的数据
    * @param string $key
    * @param int $max  最多读取条数
    * @return array
    */ 
    static public function output( $key, $max=100 ){ 
    $out = array(); 
    $mc = self::mc_init(); 
    $r_key = self::PREFIX.$key.'R'; 
    $w_key = self::PREFIX.$key.'W'; 
    $r_p   = self::set_counter( $r_key, 0 );//读指针 
    $w_p   = self::set_counter( $w_key, 0 );//写指针 
    if( $r_p == 0 ) $r_p = 1; 
    while( $w_p >= $r_p ){ 
    if( --$max < 0 ) break; 
    $v_key = self::PREFIX.$key.$r_p; 
    $r_p = self::set_counter( $r_key, 1 ); 
    $out[] = $mc->get( $v_key ); 
    $mc->delete($v_key); 
    } 
    return $out; 
    } 
    } 
    /**
    使用方法:
    QMC::input($key, $value );//写入队列
    $list = QMC::output($key);//读取队列
    */ 
    ?> 

/**
* 使用共享内存的PHP循环内存队列实现
* 支持多进程, 支持各种数据类型的存储
* 注: 完成入队或出队操作,尽快使用unset(), 以释放临界区
*
* @author wangbinandi@gmail.com
* @created 2009-12-23
*/ 
class ShmQueue 
{ 
private $maxQSize = 0; // 队列最大长度 
private $front = 0; // 队头指针 
private $rear = 0;  // 队尾指针 
private $blockSize = 256;  // 块的大小(byte) 
private $memSize = 25600;  // 最大共享内存(byte) 
private $shmId = 0; 
private $filePtr = './shmq.ptr'; 
private $semId = 0; 
public function __construct() 
{ 
$shmkey = ftok(__FILE__, 't'); 
$this->shmId = shmop_open($shmkey, "c", 0644, $this->memSize ); 
$this->maxQSize = $this->memSize / $this->blockSize; 
// 申?一个信号量 
$this->semId = sem_get($shmkey, 1); 
sem_acquire($this->semId); // 申请进入临界区 
$this->init(); 
} 
private function init() 
{ 
if ( file_exists($this->filePtr) ){ 
$contents = file_get_contents($this->filePtr); 
$data = explode( '|', $contents ); 
if ( isset($data[0]) && isset($data[1])){ 
$this->front = (int)$data[0]; 
$this->rear  = (int)$data[1]; 
} 
} 
} 
public function getLength() 
{ 
return (($this->rear - $this->front + $this->memSize) % ($this->memSize) )/$this->blockSize; 
} 
public function enQueue( $value ) 
{ 
if ( $this->ptrInc($this->rear) == $this->front ){ // 队满 
return false; 
} 
$data = $this->encode($value); 
shmop_write($this->shmId, $data, $this->rear ); 
$this->rear = $this->ptrInc($this->rear); 
return true; 
} 
public function deQueue() 
{ 
if ( $this->front == $this->rear ){ // 队空 
return false; 
} 
$value = shmop_read($this->shmId, $this->front, $this->blockSize-1); 
$this->front = $this->ptrInc($this->front); 
return $this->decode($value); 
} 
private function ptrInc( $ptr ) 
{ 
return ($ptr + $this->blockSize) % ($this->memSize); 
} 
private function encode( $value ) 
{ 
$data = serialize($value) . "__eof"; 
echo ''; 
echo strlen($data); 
echo ''; 
echo $this->blockSize -1; 
echo ''; 
if ( strlen($data) > $this->blockSize -1 ){ 
throw new Exception(strlen($data)." is overload block size!"); 
} 
return $data; 
} 
private function decode( $value ) 
{ 
$data = explode("__eof", $value); 
return unserialize($data[0]); 
} 
public function __destruct() 
{ 
$data = $this->front . '|' . $this->rear; 
file_put_contents($this->filePtr, $data); 
sem_release($this->semId); // 出临界区, 释放信号量 
} 
} 
/*
// 进队操作
$shmq = new ShmQueue();
$data = 'test data';
$shmq->enQueue($data);
unset($shmq);
// 出队操作
$shmq = new ShmQueue();
$data = $shmq->deQueue();
unset($shmq);
*/ 
?>

    class Memcache_Queue  
    {  
    private $memcache;  
    private $name;  
    private $prefix;  
    function __construct($maxSize, $name, $memcache, $prefix = "__memcache_queue__")  
    {  
    if ($memcache == null) {  
    throw new Exception("memcache object is null, new the object first.");  
    }  
    $this->memcache = $memcache;  
    $this->name = $name;  
    $this->prefix = $prefix;  
    $this->maxSize = $maxSize;  
    $this->front = 0;  
    $this->real = 0;  
    $this->size = 0;  
    }  
    function __get($name)  
    {  
    return $this->get($name);  
    }  
    function __set($name, $value)  
    {  
    $this->add($name, $value);  
    return $this;  
    }  
    function isEmpty()  
    {  
    return $this->size == 0;  
    }  
    function isFull()  
    {  
    return $this->size == $this->maxSize;  
    }  
    function enQueue($data)  
    {  
    if ($this->isFull()) {  
    throw new Exception("Queue is Full");  
    }  
    $this->increment("size");  
    $this->set($this->real, $data);  
    $this->set("real", ($this->real + 1) % $this->maxSize);  
    return $this;  
    }  
    function deQueue()  
    {  
    if ($this->isEmpty()) {  
    throw new Exception("Queue is Empty");  
    }  
    $this->decrement("size");  
    $this->delete($this->front);  
    $this->set("front", ($this->front + 1) % $this->maxSize);  
    return $this;  
    }  
    function getTop()  
    {  
    return $this->get($this->front);  
    }  
    function getAll()  
    {  
    return $this->getPage();  
    }  
    function getPage($offset = 0, $limit = 0)  
    {  
    if ($this->isEmpty() || $this->size < $offset) {  
    return null;  
    }  
    $keys[] = $this->getKeyByPos(($this->front + $offset) % $this->maxSize);  
    $num = 1;  
    for ($pos = ($this->front + $offset + 1) % $this->maxSize; $pos != $this->real; $pos = ($pos + 1) % $this->maxSize)  
    {  
    $keys[] = $this->getKeyByPos($pos);  
    $num++;  
    if ($limit > 0 && $limit == $num) {  
    break;  
    }  
    }  
    return array_values($this->memcache->get($keys));  
    }  
    function makeEmpty()  
    {  
    $keys = $this->getAllKeys();  
    foreach ($keys as $value) {  
    $this->delete($value);  
    }  
    $this->delete("real");  
    $this->delete("front");  
    $this->delete("size");  
    $this->delete("maxSize");  
    }  
    private function getAllKeys()  
    {  
    if ($this->isEmpty())  
    {  
    return array();  
    }  
    $keys[] = $this->getKeyByPos($this->front);  
    for ($pos = ($this->front + 1) % $this->maxSize; $pos != $this->real; $pos = ($pos + 1) % $this->maxSize)  
    {  
    $keys[] = $this->getKeyByPos($pos);  
    }  
    return $keys;  
    }  
    private function add($pos, $data)  
    {  
    $this->memcache->add($this->getKeyByPos($pos), $data);  
    return $this;  
    }  
    private function increment($pos)  
    {  
    return $this->memcache->increment($this->getKeyByPos($pos));  
    }  
    private function decrement($pos)  
    {  
    $this->memcache->decrement($this->getKeyByPos($pos));  
    }  
    private function set($pos, $data)  
    {  
    $this->memcache->set($this->getKeyByPos($pos), $data);  
    return $this;  
    }  
    private function get($pos)  
    {  
    return $this->memcache->get($this->getKeyByPos($pos));  
    }  
    private function delete($pos)  
    {  
    return $this->memcache->delete($this->getKeyByPos($pos));  
    }  
    private function getKeyByPos($pos)  
    {  
    return $this->prefix . $this->name . $pos;  
    }  
    }