PHP获取客户端和服务器IP地址

 /**
  * 获取客户端IP地址
  * @return string
  */
 function get_client_ip() {
     if(getenv('HTTP_CLIENT_IP')){
         $client_ip = getenv('HTTP_CLIENT_IP');
     } elseif(getenv('HTTP_X_FORWARDED_FOR')) {
         $client_ip = getenv('HTTP_X_FORWARDED_FOR');
     } elseif(getenv('REMOTE_ADDR')) {
         $client_ip = getenv('REMOTE_ADDR');
     } else {
         $client_ip = $_SERVER['REMOTE_ADDR'];
     }
     return $client_ip;
 }
 /**
 * 获取服务器端IP地址
  * @return string
  */
 function get_server_ip() {
     if (isset($_SERVER)) {
         if($_SERVER['SERVER_ADDR']) {
             $server_ip = $_SERVER['SERVER_ADDR'];
         } else {
             $server_ip = $_SERVER['LOCAL_ADDR'];
         }
     } else {
         $server_ip = getenv('SERVER_ADDR');
     }
     return $server_ip;
 }