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];
}