problem with ips

[desithugg]

problem with ips
umm just today i added a script that only lets 1 person login 1 accoutn at a time
[code]
$ipcheck = $_SERVER["REMOTE_ADDR"];
$stime=date("U")-0;
$ltime=date("U")-60;
mysql_connect("localhost", $my_sql_password, $my_sql_username) or
   die("Could not connect: " . mysql_error());
mysql_select_db("osiris_thugg");

$result = mysql_query("SELECT time FROM online where username = '$user_currently_loged' && ip = '$ipcheck'");
if (!$result) {
   echo 'Could not run query: ' . mysql_error();
   exit;
}
$row = mysql_fetch_row($result);
$loggin = $row[0];
if($loggin == "")
{

mysql_query("INSERT INTO online
(username, ip, time) VALUES ('$user_currently_loged','$ipcheck','$stime') ")
or die(mysql_error()); 
}

mysql_query("update ".$DBprefix."online set time = '$stime' where username = '$user_currently_loged' && ip = '$ipcheck'")
or die(mysql_error());

$result = mysql_query("SELECT count(time) FROM online where username = '$user_currently_loged' and time > '$ltime'");
if (!$result) {
   echo 'Could not run query: ' . mysql_error();
   exit;
}
$row = mysql_fetch_row($result);
$howmany = $row[0];
if($howmany > "1")
{
echo"There are more than 1 people logged in this account at the moment";
exit;
}
[/code]
what this does is checks if the username and ip combination exists in the table 'online'  if it doesnot exist it inserts a new record but if the combination does exist it just updates the previous record updating the time.And if more than 2 ips have been active in the last 60 seconds the user cannot do anything edit profile and stuff so this prevents some cheating.
But some users have firewalls/internet providers taht change ips constantly
[code]
username | IP
Delta Ray | 165.21.155.15
Delta Ray | 165.21.155.13
Delta Ray | 165.21.155.8
Delta Ray | 165.21.155.17
[/code]
and so on see the pattern only the last 1 or 2 numbers are being changed
so he keeps getting the error and cant do anything is there a way i cna just trim of the last 2 numbers or somehting or get by this problem

[AndyB]

Modified from code in the user notes:

[code]<?php
// reverse strrchr() - PHP v4.0b3 and above
function reverse_strrchr($haystack, $needle)
{
  $pos = strrpos($haystack, $needle);
  if($pos === false) {
      return $haystack;
  }
  return substr($haystack, 0, $pos + 1);
}

$full_ip = "165.21.155.17";
echo reverse_strrchr($full_ip, '.'); // will echo "165.21.155"
?>[/code]