When working with Smarty, a PHP templating engine, I discovered that while the regular truncate
modifier works great on ASCII strings, it doesn’t work with multibyte strings, i.e. UTF-8 encoded strings. This leads to problems in internationalization (i18n), as UTF-8 is the popular encoding for non-Latin alphabets nowdays. The problem can be solved by modifying the built-in truncate
modifier and create a new one that takes an additional argument, the charset of the string, and acts accordingly. The new modified modifier, mb_truncate
is implemented below.
Continue reading Multibyte String Truncate Modifier for Smarty – mb_truncate
Author: Guy
Multibyte String Truncate Modifier for Smarty –
A JavaScript DOS Attack
In this post I will present a way of creating a JavaScript based DOS attack that utilizes the bad implementation of tabs in most (if not all) web-browsers. The attack will make the browser unresponsive and force the user to kill its process. This attack is based on the following JavaScript code:
Continue reading A JavaScript DOS Attack
C’s “Goes To” Operator
Well it isn’t really an operator but this is a nice C code construct I ran into. It doesn’t seem to have any benefit except as a nice way to create a reverse loop:
int count = 100;
while (count-->0) {
//some work
}
As I said I don’t think I’ll find any performance benefit for using this code snippet. On the other hand it is always fun to see the puzzled face other programmers have the first time they see the code.
Optimizing for
Loops: Reverse Loops
for
loops are basic language constructs in many languages. One of the first thing to look at when optimizing code is the loops, as they do considerable amounts of work (like going through a very large amount of data), in very little code.
If you go use for
loop, but you don’t really care about the order in which the loop is executed, to be more precise, if you can afford reversing to loop, you can save quite some time. By reversing the loop I mean instead of giving the index values from 0 to 10 for example, you go from 10 downward to zero. This doesn’t seem like a big change, but when being carefully implemented this can easily upgrade the performance of your for
loops.
Continue reading Optimizing for
Loops: Reverse Loops
Creating Local SVN Repository (Home Repository)
In this tutorial I will explain how to create a local Subversion (SVN) repository, intended for a single user. I assume that you already know the benefits of keeping track of old revision of projects or important documents such as a resume or a thesis you have been writing. Subversion offers you a very convenient yet strong method to do so, and the easiest way to do so with Subversion (SVN) is to create a local, home, repository intended for a single user – you.
Continue reading Creating Local SVN Repository (Home Repository)
spass
– A Secure Password Generator Utility
spass
is a secure password generation tool. spass
was designed under the assumption that a password generator is as good as its random number generator, so spass
uses the Random
class, a /dev/random
based cryptographically strong random number generator class. As always, I tried to make the command-line interface as user-friendly as possible (as much as a command-line interface can be friendly).
Continue reading spass
– A Secure Password Generator Utility
Conditional Expressions in Python 2.4
Python 2.5 introduced new syntax structure: the conditional expressions. For programmers in languages such as C these structures seem very basic and fundamental but Python lacked them for many years. As I said Python 2.5 introduced such syntax structure, one may use it in the following form:
x = a if condition else b
As you probably guessed a
is assigned to x
if condition
evaluates to true and b
is assigned otherwise. This is pretty much equivalent to the C conditional expressions. But as I said, this structure was only introduced in 2.5. Previous versions of Python are still widely deployed and in use, so how do you achieve the same thing in older version of Python?
Continue reading Conditional Expressions in Python 2.4
ssh-keygen
Tutorial – Generating RSA and DSA keys
In this post I will walk you through generating RSA and DSA keys using ssh-keygen
. Public key authentication for SSH sessions are far superior to any password authentication and provide much higher security. ssh-keygen
is the basic way for generating keys for such kind of authentication. I will also explain how to maintain those keys by changing their associated comments and more importantly by changing the passphrases using this handy utility.
Continue reading ssh-keygen
Tutorial – Generating RSA and DSA keys
radio.py-0.4 – Listening to Radio the Easy Way
Update: radio.py 0.5 is available.
radio.py is a little script that makes it very easy to listen to radio under Linux (and maybe other OSs too) with mplayer. All you need to do is to call radio.py with the name of the station you want to listen to. For example:
radio.py Radio Paradise
or
radio.py BBC3
To read more about radio.py go to the first post discussing radio.py.
What’s New
Here are some of the things that have changed in radio.py-0.4
compared to the previous release (0.3). Continue reading radio.py-0.4 – Listening to Radio the Easy Way
The Revised String Iteration Benchmark
In this post I’m going to discuss again the string benchmark I did before to find out what is the fastest way to iterate over an std::string
. If you haven’t read the previous post on this subject go a head and read it as it covers the basic idea behind this benchmark. As I did the last time I did the benchmark, I check 5 ways of iteration:
Continue reading The Revised String Iteration Benchmark