use memcached and php-memcache(d)

For memcached 1.2 to 1.3, protocol changed for delete(). For memcached 1.4, the wrong format will cause fatal error:
failed with: CLIENT_ERROR bad command line format.
So php pecl-memcache will get failed with the new version.

for php pecl-memcached, because it’s using libmemcache, so no this issue.
We write a function to choose which memcache extension we will use in our code:

$mem_flag = 0;
$mem_conn = null;

function mcached_conn()
{
	global $config, $mem_flag, $mem_conn;
	if($mem_flag != 1)
	{
		if ($config['mcache']['version']==0){
		$mem_conn = memcache_pconnect($config['mcache']['host'], 11211);
		} else {
			$mem_conn = new Memcached();
			$mem_conn->addServer($config['mcache']['host'], 11211);
		}
		$mem_flag = 1;
	}
	return $mem_conn;
}

function memcache_version_set($memcache_obj, $key,$value,$flag,$ttl){
	global $config;
	if ($config['mcache']['version']==0){
		return memcache_set($memcache_obj, $key,$value,$flag,$ttl);
	} else {
		return $memcache_obj->set($key,$value,$ttl);
	}
}
	
function memcache_version_get($memcache_obj, $key){
	global $config;
	if ($config['mcache']['version']==0){
		return memcache_get($memcache_obj, $key);
	} else {
		return $memcache_obj->get($key);
	}
}

function memcache_version_del($memcache_obj, $key){
	global $config;
	if ($config['mcache']['version']==0){
		return memcache_delete($memcache_obj, $key);
	} else {
		return $memcache_obj->delete($key);
	}
}