note 105213 deleted from function.dechex by danbrown
| From: | danbrown@php.net | Date: | Wed, 03 Aug 2011 13:21:22 +0000 |
| Subject: | note 105213 deleted from function.dechex by danbrown | ||
| References: | 1 | Groups: | php.notes |
| Request: | Send a blank email to php-notes+get-182169@lists.php.net to get a copy of this message | ||
Note Submitter: antonio dot daeliminare dot bonifati at gmail dot com
----
jbleau algorithm is right, but it still uses 32 bit integers so that overflow will happen just like
in dechex. All operations must be done using BCMath functions. Here is a correct version:
<?php
# Replacement for standard PHP function dechex. It supports much bigger values.
function dec2hex($dec)
{
$h = array(0 => 0, 1 => 1, 2 => 2, 3 => 3, 4 => 4, 5 => 5,
6 => 6, 7 => 7, 8 => 8, 9 => 9, 10 => 'A',
11 => 'B', 12 => 'C', 13 => 'D', 14 =>
'E', 15 => 'F'
);
$hex = '';
do
{
# We could also use dechex here instead of the $h array,
# but then we would need strtoupper as well.
$hex = $h[bcmod($dec, 16)] . $hex;
$dec = bcdiv($dec, 16, 0);
}
while (bccomp($dec, 1) != -1); # That is $dec >= 1
return $hex;
}
?>