zedstar dot org » General

Adding back cdt support to eclipse (karmic koala)

john — Tue, 24 Nov 2009 12:53:58 +0000

Currently the eclipse-cdt package is missing from Ubuntu 9.10. To install cdt support do the following:

Fire up eclipse:

Help->Install New Software
Click Add
In location add: http://download.eclipse.org/tools/cdt/releases/galileo

You should be able to select this now from the drop down box titled “Work with:”

Follow it through and it will install what you need. My previous C/C++ view was ghosted so I added it again.

Building a Guile extension on an embedded device

john — Sun, 25 Jan 2009 16:45:56 +0000

Thanks to OpenEmbedded building extensions for Guile that run on embedded devices such as the BeagleBoard is fairly painless. As I have previously mentioned, Guile is already supported by OpenEmbedded. If you have an extension which is made up of some C code and some Scheme code you first should automate building it with autoconf. This might install a shared library and install some Scheme files into Guile specific locations. The next step is to write a bitbake recipe which will work with this autoconf based project. Typically this recipe will download a tarball or checkout some code from version control and then begin its magic. The end product hopefully is a binary package which can be easily installed onto the device. As an example I built packedobjects as a Guile extension for my BeagleBoard. The bitbake recipe is availabe here:

http://packedobjects.cvs.sourceforge.net/viewvc/packedobjects/packedobjects_project/openembedded/

This works by getting the latest code from CVS. It builds the code and is told which files need to be part of the package. So if you have OpenEmbedded setup you just need to issue the command:
bitbake packedobjects

This will build and package the lastest code as an ipk.

We should test the built ipk on the device to see if it works:

root@beagleboard:~# opkg install http://zedstar.org/ipk/libpackedobjects0_0.1-r0.1_armv7a.ipk Downloading http://zedstar.org/ipk/libpackedobjects0_0.1-r0.1_armv7a.ipk Installing libpackedobjects0 (0.1-r0.1) to root... Configuring libpackedobjects0 root@beagleboard:~# guile guile> (use-modules (packedobjects)) guile> (exit)

Groking Guile’s FFI

john — Sun, 09 Nov 2008 15:38:49 +0000

I have lately been very busy with work, life and the universe and subsequently have done little hacking. I have recently been examining Guile. Guile has been part of OpenEmbedded for a while so should be easy to get running on numerous embedded devices. Chicken was very recently added to OpenEmbedded, however, lacks support for building eggs in this environment. One thing I really love about Chicken is its very easy to use foreign function interface (FFI). After spending the odd hour over various weekends I have finally begun to grok Guile’s FFI. I plan to build packedobjects for Guile and possibility extend its features.

I really like the idea of extension languages ever since I did some work with Tcl a number of years ago. A great example application was Eggdrop the IRC bot. Lots of kids at the time would program their eggdrop bots using the simple Tcl interface. I think a lot can be said about this approach in terms of learning/teaching programming. I hope to explore this further with my education hat on.

Paying the price for not updating wordpress

john — Fri, 03 Oct 2008 10:42:55 +0000

I had negeleted to update wordpress for some time. The result was some iframe expoilts injected into a couple of posts. This resulted in Google reporting me to stopbadware.org. Recent versions of Firefox use data from stopbadware to warn you when you are accessing a site that may contain malware. Also, any search on my site in Google listed me with a warning and prevented linking to my site. Having fixed the issues I then had to contact Google to get myself removed from the bad list. Anyway, normal service resumed!

Booting Angstrom on my Beagleboard

john — Sun, 14 Sep 2008 22:45:49 +0000

I installed Angstrom on my Beagleboard and was able to ssh in do all the usual things. Obligatory screenshot.

I am going to install my btlogger on it and hook up a Bluetooth dongle.

Remora Project

john — Sat, 30 Aug 2008 16:19:28 +0000

I have now tested the search engine on an iPod Touch. The code and software is available here.

In summary there are 2 search engines. One does a Yahoo! search and allows you to add PDFs to the local search engine. The basic idea is you can easily add documents to your device and find and read them later using a search engine. Even if the iPhone had a way to download and browse documents it still does not solve the problem that some people give very random names to their PDF files. With the search engine you don’t need to wory what the filename is as you just search on its contents.

If you have a delicious account you can configure the live search to use it. It will then highlight any results in your search that match sites from your delicious account.

Skyhook’s LBS

john — Tue, 05 Feb 2008 23:15:52 +0000

So I downloaded Skyhook’s SDK and ran the example program. I was pretty freaked out when it located me to right outside my house! So how did it do that? Well, some time back, possibly 2 years ago I did some war driving with my Sharp Zaurus hooked up to a GPS. I literally drove about a mile and clocked up a 100 or so AP’s. I uploaded the log to wigle. So I am guessing this information made it’s way from wigle’s database to Skyhook’s. Either that or somebody else war drove past my house and provided the information to Skyhook! Anyway, I think that with some commerical backing this approach could prove very useful for location-based applications.