get_client_ip() 获取IP地址

get_client_ip()获取ip地址，在开启IPv6协议的主机上会全部返回0.0.0.0原因是他会把ipv6地址认为是非法地址而转换成0.0.0.0，而ipv4地址在ipv6主机上用get_client_ip()会放回类似::ffff:192.168.1.250这样的形式。

 /**
 * 转换IPv6地址为bin
 * @param string $ip 返回类型 0 数字 1 返回False
 * @return mixed
 */
 function ip2bin($ip)
 {
 if(filter_var($ip, FILTER_VALIDATE_IP, FILTER_FLAG_IPV4) !== false)
 return base_convert(ip2long($ip),10,2);
 if(filter_var($ip, FILTER_VALIDATE_IP, FILTER_FLAG_IPV6) === false)
 return false;
 if(($ip_n = inet_pton($ip)) === false) return false;
 $bits = 15; // 16 x 8 bit = 128bit (ipv6)
 while ($bits >= 0)
 {
 $bin = sprintf("%08b",(ord($ip_n[$bits])));
 $ipbin = $bin.$ipbin;
 $bits--;
 }
 return $ipbin;
 }
 /**
 * 转换bin地址为IPv6 或IPv4
 * @param long $bin 返回类型 0 IPv4 IPv6地址
 * @return mixed
 */
 function bin2ip($bin)
 {
 if(strlen($bin) <= 32) // 32bits (ipv4)
 return long2ip(base_convert($bin,2,10));
 if(strlen($bin) != 128)
 return false;
 $pad = 128 - strlen($bin);
 for ($i = 1; $i <= $pad; $i++)
 {
 $bin = "0".$bin;
 }
 $bits = 0;
 while ($bits <= 7)
 {
 $bin_part = substr($bin,($bits*16),16);
 $ipv6 .= dechex(bindec($bin_part)).":";
 $bits++;
 }
 return inet_ntop(inet_pton(substr($ipv6,0,-1)));
 }
 /**
 * 获取客户端IP地址
 * @param integer $type 返回类型 0 返回IP地址 1 返回IPV4地址数字
 * @return mixed
 */
 function get_client_ip6($type = 0) {
 $type = $type ? 1 : 0;
 static $ip = NULL;
 if ($ip !== NULL) return $ip[$type];
 if (isset($_SERVER['HTTP_X_FORWARDED_FOR'])) {
 $arr = explode(',', $_SERVER['HTTP_X_FORWARDED_FOR']);
 $pos = array_search('unknown',$arr);
 if(false !== $pos) unset($arr[$pos]);
 $ip = trim($arr[0]);
 }elseif (isset($_SERVER['HTTP_CLIENT_IP'])) {
 $ip = $_SERVER['HTTP_CLIENT_IP'];
 }elseif (isset($_SERVER['REMOTE_ADDR'])) {
 $ip = $_SERVER['REMOTE_ADDR'];
 }
 // IP地址合法验证
 $long = sprintf("%u",ip2bin($ip));
 $ip = $long ? array($ip, $long) : array('0.0.0.0', 0);
 return $ip[$type];
 }