[Styric]

I have written two extremely useful functions for my CMS that I think could be useful for other people.

---------------------------------------------------

Code:

function compare_paths($coma, $comb)
{
 //===== We want the directory ================

 $temp = explode("/", $coma);
 $temp = array_reverse($temp);
 if(substr_count($temp[0], "."))
 {
  array_shift($temp);
  $temp = array_reverse($temp);
  $coma = implode("/", $temp);
 }
 else
 {
  //----- No trailing slash -------------------

  if($coma{strlen($coma) - 1} == "/")
  {
   $coma = substr($coma, 0, strlen($coma) - 1);
  }
 }

 $temp = explode("/", $comb);
 $temp = array_reverse($temp);
 if(substr_count($temp[0], "."))
 {
  array_shift($temp);
  $temp = array_reverse($temp);
  $comb = implode("/", $temp);
 }
 else
 {
  //----- No trailing slash -------------------

  if($comb{strlen($comb) - 1} == "/")
  {
   $comb = substr($comb, 0, strlen($comb) - 1);
  }
 }

 //===== No starting slashes ==================

 if($coma{0} == "/")
 {
  $coma = substr($coma, 1, strlen($coma) - 1);
 }

 if($comb{0} == "/")
 {
  $comb = substr($comb, 1, strlen($comb) - 1);
 }

 //===== Remove same start ====================

 for($a = strlen($coma);$a > 0;$a--)
 {
  $b = substr($coma, 0, $a);

  if(substr_count($comb, $b))
  {
   $coma = str_replace($b, "", $coma);
   $comb = str_replace($b, "", $comb);
   break;
  }
 }

 //===== Add dots =============================

 if(strlen($comb))
 {
  for($a = 0;$a < count(explode("/", $comb));$a++) { $coma = "../".$coma; }
 }
 else
 {
  $coma = ".".$coma;
 }

 //===== And we are done! =====================

 return $coma;
}

This function makes $coma relative to $comb.

E.g.

Code:

echo compare_paths("/home/foo/bar", "/home/styric/public_html");

Would return:

../../foo/bar

---------------------------------------------------

Code:

function compare_timezones($tza, $tzb)
{
 return (intval(intval($tza) / 100) * 60)-(intval(intval($tzb) / 100) * 60)
      + ($tza / 100 - intval($tza / 100)) * 100
      - ($tzb / 100 - intval($tzb / 100)) * 100;
}

This function finds the difference between two timezones.

E.g.

Code:

$server_tz = date("O");
$server_tm = time();
$client_tz = 930;

$gmt        = $server_tm + (compare_timezones(0, $server_tz) * 60);
$client_tm  = $gmt + (compare_timezones($client_tz, 0) * 60);
$client_tm2 = $server_tm + (compare_timezones($client_tz, $server_tz) * 60);

echo "Server Timezone: "      .$server_tz."<br>"
   . "Client Timezone: &nbsp;".$client_tz."<br>"
   . "<br>"
   . "Server: "         .date("g:i A", $server_tm)."<br>"
   . "GMT: &nbsp;&nbsp;".date("g:i A", $gmt      )."<br>"
   . "Client: &nbsp;"   .date("g:i A", $client_tm)."<br>"
   . "Client: &nbsp;"   .date("g:i A", $client_tm2);

Would return something like:

Server Timezone: 800
Client Timezone: 930

Server: 11:02 PM
GMT: 3:02 PM
Client: 12:32 AM
Client: 12:32 AM