Odds and ends

Sometime around midnight last night we apparently lost net connectivity. I say apparently because, even though I couldn't ping out (even after power-cycling the ADSL modem and bouncing the firewall software) things were back to more-or-less normal this morning. May have lost some mail, though. It does appear that the machine hosting my external web pages isn't responding to pings. And I've been having trouble with Big Brother, my monitoring program. Probably ought to switch to Nagios.

Aside to texxgadget -- did you leave your glasses at the Starport last night? They're on the breakfront at the end by the TV where you were sitting...

Perversely wonderful

TiddlyWiki is one of those perversely wonderful hacks that leave you gaping in awe while wishing you'd thought of it first. You know what a Wiki is, of course: a web site full of pages that anyone can edit using text forms in their browser. Formatting is done by simple, plain-text cues like *bold* and _italics_, and CamelCaseWikiWords get turned into links automagically. It's all done with HTML forms that go back to CGI scripts on the server.

TiddlyWiki, on the other hand, is a single web page full of little cross-linked text fragments, that you edit, wiki-style, in your browser. It's all done with a lot of Javascript. If you've visited the TiddlyWiki site, congratulations! You have already downloaded the program! All you have to do is save it.

The Mandelbear goes off to a quiet corner shaking his head, which promptly explodes.

edit: Also see DocBug's blog entry on it. We both got it from mr_kurt this morning at work.

Working on the (tool)chain, gang

Most of my work these days consists of trying to shoehorn various little applications that my colleagues have written, onto a little headless ARM-based "pocket server" with the poetic name of Stargate. For various reasons, we all seem to be writing in Java these days under the mistaken impression that our code will be portable that way.

Now, several different JVMs have been ported to ARM Linux. Unfortunately the only one I could find that runs on the current version of the Stargate is JRE-1.3.something, and all of our apps are 1.4.something-else. Lots of classes snuck in between 1.3 and 1.4; many of them are even useful. So I've been looking at SableVM and the amazing gcj compiler and its gij runtime and GNU Classpath class library.

In order to compile a JVM -- or anything else -- for a little ARM box with next to no storage one needs a cross-compilation "toolchain". Luckily Debian, which is what I tend to run on my workstations these days, makes it remarkably easy to build a custom cross-compiling toolchain. Just apt-get install dpkg-cross toolchain-source and follow the simple directions in the.... Oh. Right.

Turns out the documentation is a little sketchy. Still, the basic toolchain builds very smoothly -- the details are all in /usr/share/doc/toolchain-source/README. Most of the cleverness is in the scripts that set up the build parameters and make rules so that instead of building gcc and friends, you end up building arm-linux-gcc. The dpkg-cross tpkg-install-libc script downloads libraries from the appropriate target's Debian distribution and puts them in the right place so the linker can find them when you cross-compile. Of course, that assumes that the target box is running Debian, which it probably isn't.

I'm only partway through this process -- I managed to persuade it to build gcj and gij, but not in the approved manner, so I don't yet have Debian packages to install. Oh, yes: the build process actually builds proper, customized Debian packages that you can install as usual with dpkg install.

Very cool.