fmod — Returns the floating point remainder (modulo) of the division of the arguments

If you calculate 36 modulo 7.2?  What do you get? Zero, yes. 7.2*5=36. No remainder!

What if you use fmod in PHP?

$ php -r 'echo fmod(36,7.2);'
7.2

WTF? Excuse me? Is that the result from IEEE 754 hell, a parallel universe, or what?

Now I’m betting on the function below. I hope it won’t let me down.

function modulo($n,$b) {
return $n-$b*floor($n/$b);
}

• I’m not productive enough in C++ and I feel too limited by Java
• A large chunk of Java frameworks seem to serve no other purpose than to workaround limitations in Java
• I believe (and hope!) that Java will cease to be the default language in the non-Microsoft world, and that other JVM-based languages such as Scala, Groovy and JRuby will become more important
• How can I convince a client to allow Scala, Groovy or JRuby in a project?
• I should really get some C# experience!
• It seems like I almost always resolve to PHP when I need to get something done quickly… which reminds me of an upcoming blog post about a recent fight with SoapServer and SimpleXML to implement WSSE UsernameToken authentication.

function permute($array)
{
  $results = array();

  if (count($array) == 1)
  {
    $results[] = $array;
  }
  else
  {
    for ($i = 0; $i < count($array); $i++)
    {
      $first = array_shift($array);
      $subresults = permute($array);
      array_push($array, $first);
      foreach ($subresults as $subresult)
      {
        $results[] = array_merge(array($first), $subresult);
      }
    }
  }
  return $results;
}

assert(permute(array()) == array());
assert(permute(array(1)) == array(array(1)));
assert(permute(array(1,2)) == array(array(1,2),array(2,1)) ||
       permute(array(1,2)) == array(array(2,1),array(1,2)));
assert(count(permute(array(1,2,3)) == 6));
assert(count(permute(array(1,2,3,4)) == 24));

When I tried to login to the administration interface I was told that my WordPress database needed upgrading. I thought "That’s weird!"

Some further investigation revealed that someone managed to upload a PHP script called ro8kfbsmag.txt (MD5 sum df3b74cd38c717d9d7bbf0cd1910baa1) to my /tmp directory. It starts like this:

<?php
/*Magic Include Shell by Mag icq 884888*/
//TODO: ñëèòü ôàéëî íà ñâîé ôòï (!)
$ver='2.1';
if(isset($_GET[pisun233]))
{

This gave me enough information too start googling. A must-read is Detailed Post-Mortem of a Website Hack Through WordPress & How To Protect Your WordPress Blog From Hacking, as it describes a very similar attack. There is also a support thread at wordpress.org: Weird and Dangerous : ro8kfbsmag.txt.

The attack vector on my server looked like this, originating from 78.109.21.80 with HTTP/1.0 as protocol version and "Opera" as User-Agent. I wish I logged POST data!

POST /wp-admin/options.php
POST /wp-admin/upload.php
POST /wp-admin/options.php
POST /wp-admin/options.php
POST /wp-admin/inline-uploading.php?post=-1&action=upload
POST /wp-admin/options.php
POST /wp-admin/options.php
POST /wp-admin/upload.php?style=inline&tab=upload&post_id=-1
POST /wp-admin/upload.php?style=inline&tab=upload&post_id=-1
POST /wp-admin/options.php
POST /wp-admin/options.php
GET /wp-admin/upgrade.php?step=1

Needless to say, I have restored a backup and taken certain precautions to prevent this from happening again.

One of the interesting quotes is:

Project Zero’s Chief Architect is one of the first IBMers to admit in public that Java today can be considered as a system language and is not desirable for building RESTful Web applications [...]

This was apparently a bit out of context, according to the comment by Jason McGee, but fun to read nevertheless.

He makes a prediction that shall be interesting to see if comes true:

It has taken over 10 years for the Java stronghold to admit Java’s poor ROI on the Web and with the current recession it is likely that many Java customers are going to be making more informed investments. As a result there will be considerable rise in uptake of dynamic languages.

mysql_query("SET NAMES utf8");
mysql_query("SET CHARACTER SET utf8")