While working on the new v2 release of pycall, I was doing some research on the internal limitations of Asterisk call files, and thought I'd share some interesting (technical) bits of information here.

All information below has been gathered from the latest Asterisk release (v1.6.2.7). If you don't do any programming, you may want to skip this article, as it is a bit geeky.

Last week I gave the geeks at #neverfear IRC a coding task, something I've been trying lately to both challenge them and myself. The challenge I gave them was actually a real-life problem I'd faced in industry as a developer. The challenge was as follows.

Produce an algorithm in the language of your choice that recursively converts a numerical value to a hexidecimal string without bitwise operators. Bonus points awarded for generalising your algorithm to the nth base.

We had a few good solutions mostly following a similiar approach in various languages that I'd like to share.

This is my implementation of chained hashing using the hashlittle hash function from Robert Jenkins. This code is meant for educational purposes but should be good enough for normal use (if it's not, I would love to hear your constructive critism!). I have no doubt there are more optimised implementations out there.

Check it out on its project page

Introduction

Hashing normally makes people think of cryptographic hashing often used to store passwords. Understandable considering this is what users might more familiar with. However, the principles of hashing are used for more than simply preventing retrieval of certain data.

What I'm referring to is hashing for the purposes of efficient data referencing. This is better known to developers rather than users.