I was “lucky” and got someone else’s Windows XP box to try and see if it runs, and it doesn’t. It starts up and says it needs the version of the game only works on a simplified chinese version of Windows. Then I thought, I’ve seen similar problems with other programs. Let me try fiddling with those locale and default language and encoding settings in the control panel, not to mention that I need to reboot Windows almost after every change of the settings. However, none of the changes helped. The game still won’t run. And because you could ask, no, we don’t have a simplified version of Windows.

I know for the fact that the game actually runs under WINE pretty well (good thing being an old game I guess), so I gave it a go. Installation worked. Then when I run it, yup, got the same simplified chinese version error. But there’s something different. The texts of the error dialog box are all garbage. I imagine they’re simplified chinese, but somehow not using the right font or encoding. I decided to fix this problem first, which I knew it would be easy cos I have had same problems with other chinese games before. All you need is to set LANG, in this case, to zh_CN.

And guess what, that not only solves the chinese encoding issue, that also convinces the game to think I’m on simplified chinese version of Windows. The game worked beautifully. And need not to say, setting an environment variable doesn’t require rebooting… unlike some retarded operating system.

WINE wins!

Basically I want my RSS reader to fetch things (images for example) needed to display every entry during updates, so I can read them offline. Images in most feed entries are referenced remotely (http://), which are usually not downloaded until the entry is actually viewed. Some feeds use enclosures but that works more like an attachment rather than for content.

I’ve tried quite a few RSS readers and Straw seems to be the only one that does full automatic image fetch during updates. However Straw’s development has been stalling, and the latest version seems to be quite unstable.

Liferea has been my RSS reader for quite a while, and so I’ve decided to do it myself with (hopefully) the simplest way possible: a Liferea conversion filter which parses a feed and fetches things for offline reading.

At the moment it works by looking for <img> tags and fetches the image using wget, and then replaces the original image src to point to the local one.

It’s a pretty simple perl script. I have written it in a way so it can be extended it to parse and fetch other things in the future, maybe embedded videos for example. It currently downloads all images, one by one. It also checks if a file is already downloaded or not. You can change $SAVE_PATH in the script as needed.

You can git (yes, git) the script at git://pigeond.net/offline_filter.git. Or alternatively get the latest version here, or browse the repo at http://pigeond.net/git/?p=offline_filter.git.

To use it, set the script as the conversion filter for the feed you want to have things downloaded and it should just work.

Now I can read all the really important stuff on the train, like xkcd and failblog ;).

Apart from the obvious that you need SCIM installed in the 32-bit chroot, you’ll need to set SCIM_MODULE_PATH to point to the 32-bit SCIM libdir. For instance, my iceweasel32 script looks like:

#!/bin/sh
export CHROOT=/chroot/testing.32

export GTK_PATH=${CHROOT}/usr/lib/gtk-2.0

export LD_LIBRARY_PATH=${CHROOT}/lib:${CHROOT}/usr/lib:/lib32:/usr/lib32

export SCIM_MODULE_PATH=${CHROOT}/usr/lib/scim-1.0

export MOZ_PLUGIN_PATH=${CHROOT}/usr/lib/mozilla/plugins

linux32 ${CHROOT}/usr/lib/iceweasel/firefox-bin "$@"

Secondly, you’ll need to add a symlink in /usr/lib32/gtk-2.0/2.10.0/immodules for the chroot’s /usr/lib/gtk-2.0/2.10.0/immodules/im-scim.so. Not the cleanest way I have to say, but it works.

The first is checking for vim python support before doing anything. I did this because in Debian vim (vim.basic) isn’t compiled with python support, and I prefer vim.basic over vim.gtk or vim.gnome as my default vim (and as for the reason, see my previous vimpress post.

The second is adding a :BlogSave command. Basically sending and saving an entry without publishing it, i.e. saving it as a draft, which I do a lot myself.

I’ve kept it in my git repo now at git://pigeond.net/vimpress.git

Gitweb at http://pigeond.net/git/?p=vimpress.git

Check it out at http://mpmap02.flightgear.org/. Code is in my usual git repo.

Enjoy…

Well, not really.

I was looking for an alternative to posting blog entries using the web interface, and was randomly trying a few apps in Debian. There were drivel and gnome-blog but they don’t seem to support tags. BloGTK seems to, but there’s something weird about how it does, and it doesn’t support multiple categories. BloGTK is also being removed from Debian.

Then I came across vimpress – a vim plugin for wordpress. It’s simple, but it does what I needed. You can get a list of your blog entires, post a new blog, or even edit an existing blog. So I’m testing it with this blog entry and see how it goes.

The only small rant, not to vimpress, but to Debian’s vim, is that vimpress needs vim’s python support, but it’s not built into the vim.basic binary, which I prefer over vim.gtk or vim.gnome. One of the reasons is when I ctrl-z to background vim, and then foreground it (fg), it sometimes (not all the time) gets stuck unless I hit ctrl-c. This does not happen with vim.basic, but only vim.gtk and vim.gnome.

I did try to trace it and it is when the function mch_suspend calling pause(), which causes vim to wait for a signal.

Perhaps I should report to vim later…

On the other hand, I’ve been having some issues with tailor. Not until much much much later (about a week ago) that I discovered the cause and possibly the remedy. At the same time one of the FlightGear developers Tim Moore has figured out why git-cvsimport wasn’t happy, and more importantly how to make it happy.

And so I’ve re-imported FlightGear and SimGear source from scratch and it’s been going well so far. But for those who have been using my repo, you will have to re-clone it again.

I’ve also imported the FlightGear data repo, but beware, it’s rather big even for git. The bare repo is almost 1G. So if you’re happy with your current CVS checkout, I suggest you not to bother with my git one. Mind you, that’s the entire history. Considering a checkout is about 1.7G, that’s not too bad. I’ve also set a 512kB/s limit for my git upstream, just in case there are like 20 people cloning the data repo at the same time :)

This ps3news forum post has all the goodies and explanations, how it works and what you need to do, except, it hasn’t got a Linux way of doing it. I spent some time looking into that a few months ago, and I think I should note them down here, before I forget the method myself…

The basic idea is you configure your PS3 to use a proxy, and then you tell it to download and install Folding@Home. The proxy translates the URL into a different one, i.e. you tell your proxy to rewrite the Folding@Home URL into one that points to the actual package you want to install.

To achieve that, I’ve decided to use apache, squid, and jesred. Apache and squid might be bit overkill, but that’s what I have already been using. jesred is a URL redirector in Debian that works with squid.

The download part is the same. You look for the game/demo/whatever you want and download the package (.pkg file) using the URL on the forum post. Let’s say you’ve got the file blah.pkg. Put the file somewhere accessible from your web server. For example, /var/www/ps3/ on my machine proxy1, which means I can download the file on my local network via http://proxy1/ps3/blah.pkg.

On to the squid config. In /etc/squid/squid.conf, I first define an access control:

acl myps3 src 192.168.0.123
http_access allow myps3

which allows my PS3, having an IP 192.168.0.123, to access my proxy.

I also have to add a special header_access rule:

header_access Content-Type deny myps3

which makes the PS3 happy downloading the file. Without this, the PS3 seems to refuse to even start downloading the package.

Then finally, I setup the URL rewrite:

url_rewrite_program /usr/lib/squid/jesred

which tells squid to use jesred for URL rewriting.

Now we setup jesred. Edit /etc/jesred.acl to suit your own needs. I have simply uncommented the line:

0.0.0.0/0

which allows URL rewrite from all sources.

Then we move onto /etc/jesred.rules. This is where we define our URL rewriting. First you need to know which URL your PS3 is using for Folding@Home. A list of possible URLs are shown in the 2.D of the FAQ on the forum post. My PS3 is PAL one, so to rewrite that URL to what we want:

regexi ^http://deu01.ps3.download.playstation.net/download/ps3/eu/fah/fah\.pkg 

http://proxy1/ps3/blah.pkg

(The above on one single line)

Remember every time you edit the jesred.rules file, you have to tell squid to reload (/etc/init.d/squid reload does the trick).

Finally, onto the PS3. Make sure you have set your PS3 to use your proxy. Now tell your PS3 to download and install Folding@Home.

And that’s it! I know it hasn’t got a nice GUI like the PS3.Proxyserver thing. But surely editing some text config files and running init reload scripts are that kind of things we have a passion for right?

If things don’t work, well, you can have a look at squid’s and jesred’s log. You might need to edit /etc/jesred.conf to enable its logging.

Let me know if I’ve made any mistakes, comments are also welcome.

For those who doesn’t know what bonding is, see my recent post.

Since last year, the Open Day has been yet another exciting day in LCA. There were over 30 booths hosted by different companies and organizations demonstrating their cool Linux and open source technologies.

I believe the ones that caught most attention would be the gaming booths where there were StepMania, Frets On Fire, and a bunch of open source games that were configured to use the wiimote.

And speaking of the wiimote, of course another highlight was Rusty’s Pong Hero. It was inspired by one of Johnny’s Lee wiimote project that uses the wiimote’s infrared camera and a infrared light to work together as a whiteboard. In Rusty’s case, you draw using a specially made infrared lipstick on the virtual whiteboard to play the classic Pong game. You can catch it in action on this video.

Overall the Open Day this year was great. Though I kinda hope for a better venue for it. Because it’s inside a building it’s kinda packed. I mean comparing to the one last year, LCA2007’s was a much better semi-opened area for things like Open Day.

I hung around till pretty much when then Open Day came to an end. I slowly strolled back to St Mary’s to get ready for my flight back to Sydney.

Goodbye LCA2008, and looking forward to LCA2009 in Tasmania.

In the afternoon, among the few talks I was interested, I decided to head to the MythTV BOF, partly because I know the BOFs weren’t recorded. As a quite-long time MythTV user I find the BOF pretty interesting, however I wish there was more time for it. One of the brought up issues, and also an everlasting issue, was TV guide data in Australia. I always feel funny that it is so hard to get the data, as if they don’t want you to watch their programmes.

After the afternoon tea was the lightning talks, followed by the closing of the conference. To me lightning talks are always the cool and very entertaining. Of course this year’s talks were no exception, and I enjoyed them a lot.

After the closing was the Google party. It was right outside the university union house, so it’s kinda outdoor. The atmosphere was good, and I think pretty much everyone was there enjoying the drinks and the BBQ. The food was nice, but I wish there were a bit more variety.

I stayed around for a bit and headed back to St Mary’s common room. My friend and I joined another two guys (sorry I didn’t catch the names or I just forgot :() there for a game of table tennis. I haven’t really played any double myself so that was kinda of cool.

Day 4 is the Professional Delegates Network Session (PDNS) night. Shortly after all the talks of the day we headed down to the Melbourne museum, where the PDNS was held.

I was absolutely stunned by the museum, and I just couldn’t stopped taking photos. And as a result this also distracted me from the actual “networking”. I shall put up my LCA2008 photos real soon. There was the CSIRAC – Australia’s first computer, and there were many many other cool displays of various animals and bugs, like those awesome ant’s nests and spiders.

It’s a pity though that we were only allowed to be in a rather small area of the museum, and we couldn’t really go anywhere else.

There’s also one of those displays where you put on a specially made glasses to watch a few video clips in 3D.

The food was very nice as well! There was a few things with some kind of raw beef, some thing that a bit like sushi but not quite, raw oysters, usual but delicious sandwiches. Allow me to say that the PDNS food this year was better than last year’s :P

So it was the first day of the LCA main conference. Apart from Bruce Schneier’s keynote and all the cool talks, it was also the 10th year anniversary of lwn.net, and during the morning tea we had some really really rich and delicious lwn chocolate muffin. It was soooo good.

It was also the day/night for the penguin dinner. It was held at the Queen Victoria night market, which is quite different from what the usual LCA penguin dinner used to be. And being the first time visiting Melbourne, it is actually a pretty good idea.

So we all like 700 people walking from the Melbourne University. It was funny that there was a guy who worked opposite to the road where we slowly strolled to the night market, and he couldn’t resist and headed down from his office and asked us what’s happening with all these people on the street.

We got to choose our own food from over like 30 different food places (even though I’ve got from the one only, but I loved it). And I like the semi-open environment (and glad that it wasn’t raining in the afternoon and the evening), more casual, and a lot more fun.

Didn’t pay much attention to the actual market though myself, as I found it very much the same as the one at the Rocks in Sydney.

I have been hiding in the gaming miniconf pretty much the whole day. It was all fun and cool. In particular the Crayon project, which is supposed to turn a simple photo or drawing into some sort of games, sounded very interesting. Unfortunately due to time constrains there wasn’t a demo. It might be shown on the open day however.

Another interesting one would be Rusty’s wiimote project, which will hopefully be ready to for demo on the open day as well.

As I got to St Mary’s pretty late yesterday, the registration desk was already closed by the time I got there. So only this morning I got my badge and conference bag.

One of the coolest about the bag is not only inside it has a bag for a laptop, but also the fact that it is detachable, which means I can use it in my backpack too. Another good one is the small umbrella, which I was meant to get one because my old small one broke, as they all do. Having said that, let’s hope it’s not going to rain anytime this week. :)

I managed to stay awake in the embedded miniconf with the Stuart’s robot talk and Benno’s OKL4. Both were very interesting. Unfortunately the PS3 and Cell Linux talk was cancelled, which is a bit disappointing considering I’ve recently got a (virtually free) PS3.

After lunch I went back to the embedded miniconf for more talk, then later I hopped into the multimedia miniconf for the Ingex talk. After that I just couldn’t talk it anymore and decided to stroll back to my room and take a nap.

Definitely need a longer and better sleep tonight for the gaming and perhaps kernel miniconf tomorrow.

And once again, like many other LCAers, I’m really grateful for the working wireless at the St Mary’s college rooms. Thanks very much to the LCA team.

Also just wondering if there’s any other FlightGear-ers around LCA this year? (apart from those who I already know). We could have a little chat, or maybe some hacking/debugging/troubleshooting sessions? Or even some multiplay fun?

See you all at LCA!

Anyway, here’s a possible quick fix for those with an ASUS laptop (W7J at least) and a non-working brightness acpi key (in my case, it’s Fn + F5 and Fn + F6), even though /sys/class/backlight/asus-laptop/brightness works perfectly.

I poked around the disassembled DSDT code and did a bit of googling. After a few reboots and testing, I figured out passing acpi_osi="!Windows 2006" to the kernel fixes the issue.

Apparently with the (current) Linux ACPI driver, the OS interface (OSI) code will respond to the ACPI as quite a few different versions of M$ windows (see drivers/acpi/utilities/uteval.c for the entire list). This list can be modified by the kernel parameter acpi_osi (see Documentation/kernel-parameters.txt for full details).

So my guess is the DSDT thinks I’m running “Windows 2006″ (aka Vista), and so it is doing (or not doing) something with these two particular ACPI keys. Telling the Linux ACPI driver not to pretend to be Vista got rid of the problem.

This quick workaround also means that I didn’t have to patch my own DSDT and build a kernel with it.

[Updated: 5th November 2007] I was testing 2.6.23.x on the W7J, and I noticed both brightness keys Fn + F5 and Fn + F6 work without acpi_osi. I looked into it and I’ve found out that the ACPI video driver makes the keys work. And for some reasons with older kernels (2.6.22.x) the video module is not loaded automatically. So you can probably ignore what I said above months ago :)

Switching between the two networks is not a big deal. And with the help of ifplugd, the switching is automatic. But after all, they are two different interfaces. It would be good if I could switch between them without losing any existing connections. After a bit of googling around, I’ve found one solution: Ethernet channel bonding.

From the Linux source code Documentation/networking/bonding.txt: “The Linux bonding driver provides a method for aggregating multiple network interfaces into a single logical “bonded” interface”. In my case, I’m bonding the eth0 (wired) and the eth2 (wireless) together.

Under Debian, the bonding driver is built as a module bonding. I’ve also installed the ifenslave. So I put the bonding driver into my /etc/modules so it’s loaded at system startup:

bonding mode=1 miimon=500

where mode=1 sets the bonding mode to active-backup. The bonding driver also supports a few different load-balancing modes, which you might want to check out as well. miimon=500 sets the link check interval in milliseconds.

There’s also a primary parameter which you could specify which slave interface will always be used if it is available (e.g. primary=eth0).

The bonding driver gives you a new network interface bond0. Now to setup bond0, eth0 and eth2 in /etc/network/interfaces:

# the wired interface
iface eth0 inet manual
    hostname xxxxxxx

# the wireless interface
iface eth2 inet manual
    wireless-key s:xxxxxxxxxxxxx restricted
    wireless-essid xxxxxxxxxxxx
    wireless-mode managed

# the bonding interface, eth0 + eth2
iface bond0 inet dhcp
    pre-up ifconfig bond0 up
    pre-up ifenslave bond0 eth0 eth2
    pre-down ifenslave -d bond0 eth0 eth2

bond0 is set to use DHCP, while eth0 and eth2 are not, as they will act as slave interfaces. bond0 is the master. The 2nd pre-up command for bond0 attaches both eth0 and eth2 as slaves to the bonding device. Note that it is possible to configure a bonding device via sysfs, which is also documented in Documentation/network/bonding.txt.

While ifplugd takes care of eth0 going up and down, I also want to turn off the wireless completely when the wired network is plugged in. So I added my own script /etc/ifplugd/action.d/bonding:

#!/bin/sh
set -e

if [ ! -f /proc/net/bonding/bond0 ]; then
    exit
fi

case "$1" in
eth0)
    case "$2" in
    up)
        /sbin/ifdown eth2
        /sbin/ifconfig eth2 down
        /sbin/iwconfig eth2 txpower off
        ;;

    down)
        /sbin/iwconfig eth2 txpower auto
        /sbin/ifup eth2
        /sbin/ifconfig eth2 up
        ;;
    esac

    # I need to do this sometimes, so I've put it in
    # or could someone comment on this?
    ifdown bond0
    ifup bond0

    ;;
esac

This script will turn off the wireless radio for me when my eth0 wired network is up.

I’m relying on ifplugd to bring up bond0, which will then bring up eth0 and eth2. Hence in /etc/network/interfaces I did not set any of the interfaces to be auto. I also added -l to the arguments of ifplugd in /etc/default/ifplugd:

ARGS="-q -f -u0 -d10 -w -I -l"

so that it will run the “down” script on ifplugd startup if no cable is detected. That way my script will bring up my wireless eth2 if eth0 is not plugged, say at boot time.

With this setup, the bonding driver automatically switches to use eth0 or eth2, whichever is brought up. In my setup, eth0 and eth2 won’t be up at the same time. If you use the primary parameter, the primary slave interface will always be used, even if the other slaves become available.

/proc/net/bonding/bond0 shows the status of the bonding interface. For example I’m now on the wireless network:

Ethernet Channel Bonding Driver: v3.0.3 (March 23, 2006)

Bonding Mode: fault-tolerance (active-backup)
Primary Slave: None
Currently Active Slave: eth2
MII Status: up
MII Polling Interval (ms): 500
Up Delay (ms): 0
Down Delay (ms): 0

Slave Interface: eth0
MII Status: down
Link Failure Count: 0
Permanent HW addr: 00:11:2f:9c:57:25

Slave Interface: eth2
MII Status: up
Link Failure Count: 0
Permanent HW addr: 00:11:2f:9c:57:25

It’s pretty obvious that the currently active slave is my eth2 wireless. I can run something like watch -n 1 cat /proc/net/bonding/bond0, and as I plug the ethernet cable back, the active slave will become eth0. You can also find out the currently active slave via /sys/class/net/bond0/bonding/active_slave.

For completeness, here is the output of ifconfig:

bond0     Link encap:Ethernet  HWaddr 00:11:2F:9C:57:25
          inet addr:192.168.11.3  Bcast:192.168.11.255  Mask:255.255.255.0
          inet6 addr: fe80::211:2fff:fe9c:5725/64 Scope:Link
          UP BROADCAST RUNNING MASTER MULTICAST  MTU:1500  Metric:1
          RX packets:329306 errors:0 dropped:0 overruns:0 frame:0
          TX packets:329010 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:732552585 (698.6 MiB)  TX bytes:204431117 (194.9 MiB)

eth0      Link encap:Ethernet  HWaddr 00:11:2F:9C:57:25
          UP BROADCAST SLAVE MULTICAST  MTU:1500  Metric:1
          RX packets:303936 errors:0 dropped:0 overruns:0 frame:0
          TX packets:304693 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:245381818 (234.0 MiB)  TX bytes:27905638 (26.6 MiB)
          Interrupt:5 Base address:0xd800

eth2      Link encap:Ethernet  HWaddr 00:11:2F:9C:57:25
          inet6 addr: fe80::211:2fff:fe9c:5725/64 Scope:Link
          UP BROADCAST RUNNING SLAVE MULTICAST  MTU:1500  Metric:1
          RX packets:25370 errors:0 dropped:0 overruns:0 frame:0
          TX packets:24317 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:487170767 (464.6 MiB)  TX bytes:176525479 (168.3 MiB)
          Interrupt:5 Base address:0xe000 Memory:ff9fe000-ff9fefff

which shows bond0 being the master, and eth0 and eth2 being slaves.

It almost makes plugging and unplugging the ethernet cable fun. I can just sit there and keep replugging the cable alllllll day… :)

I’ve been using this setup for at least a week now and has been working very well. Please let me know if there’s anything I’ve missed, or any even better way of setting this up.

And of course it works under that proprietary . Then we realized it has rather serious issues with the composite-in being a bit slow (both slow frame rate and sometimes laggy).

As a Linuxer, naturally I then tried the device under Linux. Only just halfly expected, there is no driver for Linux yet. That’s no better way to spend your holidays overseas? I decided to spend a little on looking into the possibility to reverse engineer the windows driver.

Doing things on windows is always painful. Though I got one of the windows USB sniffer working, it wasn’t as convenient as doing things on Linux. So I went for using QEMU booting into windows and capture all the USB traffic. Unfortunately, windows (xp) crashes (classic BSOD style) while installing the device driver. I thought for a second, maybe it’s QEMU not emulating something that is needed?

Someone on #bochs pointed me to VirtualBox, so I gave it a go. Still out of luck though, windows xp crashes at the exact same spot. Damn.

On the bright side, I have discovered VirtualBox – yet another virtualizer for x86 hardware, and it’s pretty awesome:

• (On this Pentium M 1.6GHz laptop) VirtualBox is much much faster than QEMU (with kqemu) for, well, running windows xp.
• It has a GUI frontend for setting up VMs. As much as I prefer text/command-line based apps, a GUI frontend does help new users to try things out a lot.

Having said that, VirtualBox (currently anyway) is not entirely open source. It has two editions. And the version I tried was the one with those closed-source features. On the other hand they did say “some of these features will eventually be made available with the open-source version as well”.

So, no, I didn’t go very far with the reverse engineering. It’s usually a painful and time-consuming process. I did have some of the USB traffic sniffed and logged under windows, but I haven’t done much with them yet.

I have some more photos and info of the device here, including photos of it pulled apart.

I’ve finally switched my gateway box from my 12 years old Pentium (I) 166MHz gateway box (still running Debian potato, kernel 2.2. This is Linux for you, when it works, it can work forever…), to my 5-6 years old Netwinder.

I was also very glad that the Netwinder is now (or still) officially supported by Debian. I had Debian potato installed on it for years. Upgrading it was painless.

My old gateway box was running such an old kernel, and the firewall was one of those copied-from-others script using ipchains. This time I decided to use a better way to manage my firewall rules. After a bit of research and trying things out, I’ve chosen ipkungfu. Again, it was painless to setup.

The only not-so-good bit was, I did the machine switching-over only 1 day before I went away. So as it turned out, my net connection went down in about 2 days time. I always have some scripts checking if the net is up or not, and it would reset everything (bringing down/up the interface, renewing IP, relogging on, etc). But looks like that wasn’t helping either. So I thought it might be one of those cable-modem-needed-to-be-reset situation.

I asked my uncle to power cycle the cable modem for me. And just to be safe I asked him to do the same for the gateway box too. As expected my net connection went up again. And I was happy, for a while.

Who would have thought, it went down again. Suspiciously, it also only stayed up for about 2 days. My instinct told me it wasn’t a coincident. A few days later my uncle again power cycled the modem.

I got on and check the logs again and found that my firewall was blocking (and logging) a lot of IGMP packets from some mysterious 10.x.x.x (Telstra internal network instruments) IP. It’s strange though, I haven’t seen these logs when I was testing the net. So apparently just the bpalogin client heartbeat is not enough. Seems that without the IGMP packet response (or how-ever IGMP works), after a certain timeout period (2 days?) the other end terminates the net connection and stops leasing IP, even if the cable modem is on or even there are existing network connections. So of course, I’ve then updated my firewall rules.

Lesson learnt, testing the net for 1 day is not enough, cos it will go down in 2 days ;)

Once again, many thanks to my uncle for the trouble.

The highlight talk for me for the day was probably Adam Kennedy’s Nothing can possibly go wrong. Couldn’t quite describe it, just wait and download its video if you weren’t there.

And then there was the closing ceremony of LCA 2007. Like most people I would have loved it if the space invader demo worked. Even if we could setup a camera and write a program to do the same thing, we certainly don’t have like 800 people to test it everyday.

We progressed to the Penguin Dinner shortly after. It was a big dinner, apparently there were about 65 tables. Food was great even after having a bad stomach after the Open Day beef pie. During the dinner there was the rusty wrench presentation, the big cheque handing over, and also the usual speaker-autographed auction. After the dinner we had a little final party upstairs at the same place. I spent only a little bit there.

Photos of the last day of LCA here.

While Alexander Reeder presented his neat, practical and yet simple idea of his naked laptop weather display in the Open Source Art talk. He has reminded me of the broken laptop my ex-flatmate gave me, which has a rather flaky IDE bus as well. I should probably think of something cool to do with it.

In the afternoon we had the ROCKING Open Day at the pavilion. Though the venue is small (comparing to those big expo of course), there were heaps of interesting displays and demo. It might be things that we (Linux enthusiast) see everyday, but to the others it was a wonderful experience. It was very packed and apparently there were over a thousand people visited, including families and friends of people in the Linux community. Maybe this will become a trend of all LCAs in the future to have an awesome Open Day.

I ended up helping Endy a very little bit at his ScummVM demo stand. I showed and explained to a few kids the what and how of the game. Turns out there were a lot of young kids interested Sam ‘n Max and the Maniac Mansion Day of the Tentacles when they saw them. Many of them were willing to sit down and spend lots of time going though the game. Good games can really be good games of all time.

Photos of day 4 here.

The X talk reminds me of xdmx, which works but the version I tried last time still had the nasty Xrender bug (which is apparently fixed in the development version). Also I couldn’t get any GLX direct rendering to work, even for the local native screen which I thought it would work. Someone could show me some lights? (Is it supposed to work or not?)

In the evening we had the professional networking session at the Scientia. This is actually my first time at LCA as a professional. The atmosphere there was great. There were a lot more people there than I thought it would be. Took some nice photos there too.

Photos of the 3rd day here.

Jono Bacon pinpointed that a few good elements that what and how a (sound editing) GUI would make sense and be intuitive. I have played with ardour a little bit myself and I have to agree what Jono has said about it. I guess it’s kind of like how I keep hearing people who got used to a 3D modeling app like AC3D and then go and try Blender. (I use and am used to Blender, though)

Well, spent most of the day at the Gaming Miniconf. Wesnoth, PS3 Linux, and so forth.

Also fulfilled my panorama obsession and half-heartedly took one at the round house while people waiting for the conference party. No I haven’t fixed every single glitches in the photo, that’s what the GIMP tutorial on Thursday is for :)

It was pretty exciting to meet for the first time with a few people who I have known online for quite a while. George (or Gorilla) from the FlightGear gang, Leeds I know from #handhelds.org, and Endy from the ScummVM team showing off the latest version that has AGI support (for some of the old Sierra games like Space Quest I). Looking forward to his lightning talk at the Gaming Miniconf tomorrow.

Apparently Jeff ended up demonstrating the Wii in the Gnome miniconf (which I have missed). I reckon he should have demo using the Wiimote on Linux, which is pretty easy to setup. Or maybe that should be in the Gaming miniconf… :)

On the other hand, I was having weird trouble with the wireless on my laptop. It’s a Intel Centrino PRO/Wireless 2200BG, and I was using the ipw2200 module with the corresponding firmware. For some reasons it wasn’t able to get an IP from DHCP most of the time. I managed to get an IP once, but it dropped out pretty much straight away. I tried setting the same IP I got statically but it was only partially working (DNS working, for example, but nothing else worked, which was expected).

After consulting Jamie and John a bit they reckoned my wireless somehow kept dropping packets. And to be honest I haven’t actually use the wireless much on this laptop. I have no idea whether it’s a hardware/radio/firmware/driver problem or what. I ended up using my CF wifi card and it worked beautifully.

Anyone in the conference is welcomed to fix it for me :)

Took fewer photos than I wanted to today, but anyway they can be found here. I’ll try to put up new photos there for each LCA day.

With thanks to WMD, you could use the Wiimote under Linux fairly easily. For those who don’t know Wiimote talks to the Wii console via bluetooth. So it works with any computer with bluetooth as well.

People have been using the Wiimote on the computers in all sorts of different ways. As a guitar (Wiitar), as a drum machine, for games like Counter Strike, a virtual light sabre, etc. As for me, using the Wiimote with a flightsim, like FlightGear, would naturally be the first thing I wanna try.

The Wiimote has three accelerometers for the three axes. I’ve modified slightly the WMD script to send the X and Z force to the uinput device as the absolute coordinates. jscal then takes care of the calibration of the two axes. Then I changed the commandMap in the script to send BTN_0 to BTN_9 from all the buttons on the Wiimote.

On the FlightGear side all I need is to write a joystick definition XML for the Wiimote. I’ve also made the ‘B’ button to be the modifier. For example I have arrow Up and Down for throttle, Left and Right for the rudder. Then if I hold down ‘B’, Up Down Left Right become panning the viewport. ‘1′ and ‘2′ for changing views, ‘+’ and ‘-’ for zooming in and out, ‘A’ for brakes and gears. All set. Now I can fasten my seatbelt^H^H^H^H^H^H^H^Hwrist strap, sit back and ready for take off.

Updated 5th Jan 2007: Here is a patch against WMD SVN repository. Like I said it’s pretty hacky at the moment. And you definitely have to use jscal to calibrate it before it will behave sanely. Also you probably want to make changes to the commandMap in wmd/Config.py to map more buttons.

And for those FlightGearers out there, here is the Wiimote joystick XML config I’ve made.

Here’s a video of FlightGear + Wiimote in action:

The quickest hack I did was the GE version FGMap, which shows a moving map of all the online pilots on the FG MP servers. It is basically a very simple change with the FGMap CGI that translate MP server info into XML, only this time it outputs KML. Very simple and straight forward, nothing fancy at all. Check it out by opening this file in GE (if no one is on the server, you’ll see nothing! Check FGMap too).

Quickly I found this Collada exportor plugin for Blender. As a test I loaded the C172P aircraft AC3D model from FG into Blender, followed by a few trail-and-error and I figured out what I need to export for GE: 1) Convert all faces to triangles, 2) Export Triangles, Disable Physics, Use UV Image and optionally Use Relative Paths.

According to the KML tutorial I have to pack up the .dae file together with the textures, along with a textures.txt for textures path mapping. However I discovered you could actually alter the path referenced in the .dae file to a local jpeg file, or even an HTTP URL.

So now I’ve got GE to show a 3D model of an aircraft from FG. Next is to get FG to talk to GE. There are many ways (network, serial port, etc) in FG you can export real time flight data. To make things easier for now, I’ve set it up to export simply latitude, longitude, altitude, pitch, roll, heading to a file (or actually a fifo), then I wrote a little program to read and output a KML file for GE to read. Then on the GE side, I have to create a KML with a NetworkLink to refresh the actual FG KML.

Now, problems. It seems even if I set the refresh time to be 0 seconds, and I can see GE refreshing the link continuously, on screen it still only updates the position/orientation about once per second. It could well be a GE internal limitation (or feature). The bottom line is, we need a sane way to feed data into GE.

Another thing is I can never get GE to “follow” the aircraft properly. It’s either not panning faster enough, or it will go kinda crazy and jitter a lot. Guess I’m not a GE/KML yet. I need to test it more and tidy up my codes/scripts/things a bit and I’ll put them up.

Nevertheless, it’s kind of fun to “fly FG inside GE”.

Screenshots of FlightGear running side by side with Google Earth, whereby FG sending data to GE and showing the 3D aircraft. Possibly more screenshots here

KSFO

Hong Kong with Computamaps Hong Kong 3D models

Also I’ve added external links in the airport info box to World Aero Data and AirNav (for U.S. airports).

I got there sometime just before 11 I think. Weather wasn’t very good and quite windy from time to time, but it was very comfortable as I was definitely not sweating, a lot better than one of those 37 degree weekends (which was the week before). It was very crowded, with a lot of families with kids and everything.

So I was pretty much standing and walking around for over 6 hours, taking photos, watching flying demos and aircraft displays. It’s absolutely good fun if you love planes. For me maybe it was too much of a warbirds and fighters show, but still very enjoyable. There were aerobatics, formation flying, attacks demo, helicopter joy riding (which I didn’t do, it wasn’t free :P), also some R/C aircraft and gliders displays. F-111, Hornets, Hercules, Boeing 707, Vampire, Tiger moth, and many many more…

I took almost 300 photos in total, though most of them look pretty dark and dull due to the weather. And to satisfy my panorama need, I’ve taken a 360° panorama view at the base at the end of the day.

Note to self:

• Need better camera for this kind of show, a DSLR with like a 30x optical zoom lens would be great :)
• Hang around at the end of the day when almost everyone are leaving, perfect time for taking even more photos wherever and however you like, without the extra random people.

My RAAF airshow 2006 album is here.

And for the (first) best thing, LCA 2007 registration is now opened!

Now how cool is that! (Or I should just get out more…)

And so one thing leads to another. I setup Xinerama for the 2 screens. I played with DMX across the 3 screens for a bit. It’s nice but for some reasons it’s not doing direct rendering for GLX, neither the local nor the non-local clients.

And then the most obvious and exciting thing to do is to run multi-head FlightGear. As my setup is 3-screen-on-2-machines, normally you’d simply run one FlightGear on each machine. However my 1-screen-machine is rather old and slow, and not much memory (Pentium 2 w/256MB ram). So I ended up running two instances of FlightGear on the 2-screen-machine (Pentium 4 w/1GB ram) and forwarding the display onto the other (by setting DISPLAY). Its startup time is a lot faster this way.

When I have the time I should play with Chromium as well…

The Golden Gate Bridge across 3 screens

Flying over San Francisco

A little bit of surprise, it ran with Wine latest development version, at least it’s gone thru all the splash screen, characters selection, until it gets to the actual game, crashed.

After turning on some debugging and tracing, followed by consulting on #winehq, I’ve learnt that this game hits one of the famous Wine and DirectX issue, multi-threaded Direct3D.

Still I’m a bit adventurous as usual, and did a bit of code reading and hacking in Wine, trying a few different quick-and-dirty approaches to get threads to use the same GLXContext, not that I’m an OpenGL guru.

After a few tries, I gave up. However I still kind of wanna be able to play this game under Linux. So I rethink the problem from a different approach, and did a even more dirty hack, so that only the main thread can do any GL calls. Any other threads will simply returns before trying. Yes, VERY UGLY indeed. So ugly that let’s not even talk about it anymore ;)

And guess what, that does the trick. It gets into the actual game. So apparently it’s creating a new thread only for the pre-game loading screen. So now instead of the loading animation screen, I simply get a black blank screen, and the game continues after that.

And just for fun, I’ve even created a character with the top Taiwanese model’s name :P

More screenshots here.

Back in January when I was in Taiwan, my wife and I went up to Taipei from Tainan on one of those buses. It was a roughly 4-hour trip. For those who haven’t been to Taiwan, these are not normal buses you catch to work everyday. These are more like those for tourist, pretty luxurious, comparatively speaking. The one we took was from a bus company called Ho-Hsin (和欣).

There are only about 15 seats on one bus. Each seat is a huge sofa-like massage chair, which you could pick your own massage programme with the control panel embedded under the chair arm. You can also adjust your chair with it, too, very much like those seats in the first class on an airliner. Even more, each seat has a small LCD TV screen showing information of the current bus route. You can switch it to the live TV news channel, or pick a TV show or a movie. And if you’re not so much of a watcher, you can always grab the joypad controller attached to the chair and choose from around 20 different video games to play.

The interior

The control for the massage chair

The main menu, for choosing movies, music, TV shows, games, etc…

I was playing a baseball game…

Now set aside all these cool “stuff” with the bus, as a embedded software developer, I’ll always try to figure out how the whole system works, what software they’re running, etc. Just when I thought I didn’t really care while I was on holidays, and, there was it! The “X” I saw! It came up when I selected a movie. It’s running X, and possibly, on Linux!

(Feel free to correct me if it’s not, or if you know more about their system and if you’re allowed, please tell me too :)

X, that made my day…

That surely made the trip a bit more exciting :)

Next step I was trying to get suspending working. ACPI sleep state S3 (Suspend to RAM) works pretty well as expected. However when the laptop comes back from the suspend, there seems to be a delay, or timeout, or some issues with USB. As this rootfs is on USB, I’m getting read errors, and from that point on, the rootfs has gone to a funny state, and things stops working.

The easiest way to solve this problem for the moment, to me, is to totally avoid the problem. I need to get Linux running off the harddisk on this laptop. And at the same time I do not want to install, or repartition the existing windows installation. So I decided to go for loopback rootfs.

The loopback rootfs on Linux is not anything new. I briefly did a google search and there’s this loopback root filesystem HOWTO written back in 1999. Though, I want to get this done in a maintainable way. Being a Debian user, hence, I want to do this in a Debian way.

For this Linux live system, I’ve been a good Debian user and keep everything done in the Debian way, so that it’s easier for me to manage, recreate, and update/upgrade the system. Kernel initrd image is handled by initramfs-tools. So rather than putting together an initrd image manually to do all the tricks, I quickly looked at how initramfs works, and wrote a loop script, which is pretty much the same as the existing local script, but with one extra step. And I’ve also added a few more kernel parameters to make things easier. Here it is:

# Local loopback filesystem mounting

# Parameter: Where to mount the filesystem
mountroot ()
{
        for x in $(cat /proc/cmdline); do
                case $x in
                rootfstype=*)
                        rootfstype=${x#rootfstype=}
                        ;;
                loopfile=*)
                        loopfile=${x#loopfile=}
                        ;;
                loopfstype=*)
                        loopfstype=${x#loopfstype=}
                        ;;
                esac
        done

        [ "$quiet" != "y" ] && log_begin_msg "Running /scripts/local-top"
        run_scripts /scripts/local-top
        [ "$quiet" != "y" ] && log_end_msg

        # If the root device hasn't shown up yet, give it a little while
        # to deal with removable devices
        if [ ! -e "${ROOT}" ]; then
                log_begin_msg "Waiting for root file system..."
                if [ -x /sbin/usplash_write ]; then
                        /sbin/usplash_write "TIMEOUT 180" || true
                fi

                slumber=1800
                while [ ${slumber} -gt 0 -a ! -e "${ROOT}" ]; do
                        /bin/sleep 0.1
                        slumber=$(( ${slumber} - 1 ))
                done

                if [ ${slumber} -gt 0 ]; then
                        log_end_msg 0
                else
                        log_end_msg 1 || true
               fi
               if [ -x /sbin/usplash_write ]; then
                       /sbin/usplash_write "TIMEOUT 15" || true
               fi
        fi

        # We've given up, but we'll let the user fix matters if they can
        while [ ! -e "${ROOT}" ]; do
                panic "ALERT!  ${ROOT} does not exist.  Dropping to a shell!"
        done

        eval $(fstype < ${ROOT})

        [ "$quiet" != "y" ] && log_begin_msg "Running /scripts/local-premount"
        run_scripts /scripts/local-premount
        [ "$quiet" != "y" ] && log_end_msg

        # FIXME This has no error checking
        modprobe -q ${FSTYPE}

        # FIXME This has no error checking
        # Mount root
        mkdir /preroot

        if [ "${rootfstype}" ]; then
            opts="-t ${rootfstype}"
        fi
        # mount the device containing the file image as rw
        mount -w ${ROOTFLAGS} ${opts} ${ROOT} /preroot

        [ "$quiet" != "y" ] && log_begin_msg "Running /scripts/log-bottom"
        run_scripts /scripts/local-bottom
        [ "$quiet" != "y" ] && log_end_msg

        if [ "${loopfstype}" ]; then
            opts="-t ${loopfstype}"
        fi
        # mount the file image loopback
        mount -o loop ${opts} /preroot/${loopfile} ${rootmnt}

        if [ -e "${rootmnt}/preroot" ]; then
            # bind mount the real device so that it is accessible later
            mount -o bind /preroot ${rootmnt}/preroot
        fi
}

With this file in /usr/share/initramfs-tools/scripts/ or in my case, I simply made a copy of what’s in /usr/share/initramfs-tools/ and /etc/mkinitramfs/ and run mkinitramfs -d <confdir> -o initrd.img-pikkoro.loop. Anything I’ve done is adding modules I needed in the “modules” file. Mine looks like this:

usbcore
ehci-hcd
ohci-hcd
uhci-hcd
usb-storage
sd_mod
loop
ext2
ext3
vfat
jbd
nls_iso8859_1
nls_cp437

I’ve created a 4GB ext3 filesystem in a file, stored on the windows fat partition. In my case, the loopback file is on the windows partition /dev/hda5, with the path /pigeon/pikkoro.img. So my kernel parameters are:

root=/dev/hda5
boot=loop
rootfstype=vfat
loopfile=/pigeon/pikkoro.img
loopfstype=ext3

(shown in separate lines here for each parameter to make it clear)

And that’s it. Now I can boot this laptop via USB, then run Linux with the rootfs on the filesystem file, mounted as a loopback. And more more importantly, suspend-2-ram and resume is now working well.

So I bought myself a 2GB CF card when I was in HK months ago. And I’ve finally finished setting Linux up on it. Host name “Pikkoro” (yes, yet another machine named after Dragon Ball characters), got Debian Etch (testing) installed, have it booting and running my own Linux system using a USB-CF card reader.

For those who are not familiar with the idea of a “live” system, it is basically an operating system (Linux in this case) installed on any media that can be used to boot on a computer. We all know the common setup of your computer booting the OS installed on your harddisk. So your harddisk is “bootable”. These days most computers can boot not only from a harddisk, but also from a CD/DVD, or a USB storage device (aka USB drive/stick). A live system would mean the OS/system can be run without installation. It won’t touch your harddisk (unless you want to).

So in my case, I have Linux installed and setup on my CF card, which can be plugged to a computer via a USB-CF card reader. The reason why i didn’t use a USB stick/drive is so I can use/read it on my iPAQ too, which has a CF slot.

Getting a Linux live system to work is pretty easy if you’re familiar with how Linux boots and how Debian works. Nevertheless I did some searches and reading on what other people have been doing, and I found this mini guide. What interested me is the localepurge package in Debian, which saved me a some disk spaces.

One of many things during the process was picking a window manager (notice how I said “window manager”, but not “desktop environment” :) I’ve been an AfterStepper (1.8) for a long long time. When I was doing FGLive I played with fluxbox a bit and I liked it. So I’ve decided to give it a go. After fiddling with it for a while, it’s official, fluxbox is now default on my Linux live CF. Its tab feature is probably one of the coolest. My only complaint so far is it not able to switch virtual desktop by mouse, and the fact that it only has concept of linear virtual desktops it seems.

Anyway, I’m now happy that I can carry around my own Linux system anywhere I go…

To find out more about FGLive, see here, and make sure you read the README as well.

See screenshots and videos of FlightGear here.

And so I started off doing it. It’s heaps of fun, not to mention finding out all those bugs with IE. M$ is very kind, they always do things that make people laugh. This always gives me a chance to revise a lot with Javascript.

I also ended up writing my own routines for map overlays displaying plane markers and info, instead of using the GMAPI’s GMarker. A bit more flexible, and it does exactly what I want.

There is time when Javascript is useful, and there is time where it’s just overkill. IMHO, Javascript is useful for writing “web app”. Same as using Flash, or Java applet. But btw this does NOT mean every website should be bloody web app!!

And there you go, the FlightGear server online map. A couple of FlightGearers have been using it as a flying map and as a simple ATC radar. If it’s the right time you’ll see us flying!

I’ve got plans to add more features, like airports/navids lookup. And of course, improving the usability and UI is always on the plate. Comments are also welcomed…

Also thanks to everyone who has helped me with testing and giving suggestions to the page. (ampere, AJ, thorben, vivian, gorilla, Surge, johnh51, MasseR, etc)

I was never into wireless stuff as I always think they hurt my brain and give me headaches. Then I was thinking everyone is going to be using wifi at LCA, i.e. 499 wireless cards is not going to be any better than 500. And so I’ve bought a CompactFlash wifi card for my iPAQ about 2 weeks before the conference. And it’s working very well under Familiar 0.8.x. It pretty much works straight away. So I was using wireless on my iPAQ happily for the entire LCA.

I went to the Embedded Miniconf on the first day. I quite like Chris McCormick’s 10 embedded tricks for coding on the Gameboy Advance talk. I also went to his Gameboy Advance talk on the last day of the main conference. He mentioned his little music program for the GBA called looper. I wonder how hard it would be to port it onto Linux and perhaps my iPAQ…

Keith Packard’s talk on Twin was also very interesting especially when he brought up stroke fonts again. I saw someone talking about stroke fonts when I was googling around looking for ways to reduce the footprint of ttf fonts. If you’ve played with Chinese or Japanese ttf, sure you’ll know they are usually very big (>10-15MB), and hence not very nice on devices like my iPAQ. Stroke fonts on the other are much much smaller. However there isn’t seem to be any open source implementation and support for stroke fonts at the moment :(

Then on the second day I went to the Audio Miniconf. The sound demo by Mark Greenaway was quite amazing as he showed off a couple of Linux audio/music programs, including with ardour, seq24, hydrogen, alsamodularsynth, meterbridge, etc etc. Now I can waste more time playing around other than just with rosegarden :)

Some other random LCA notes:

- Everybody can implement their own BitKeeper client. All you need is to ask for “help” :)

- The Golden Penguin Quiz show was simply fun, and also it suggested that how little I know about things :)

- After the Penguin Dinner night, we’ve all discovered a new way to kill productivity by apt-get install wesnoth.

- Must check on James Cameron’s Remastering Knoppix notes so we can setup the one-command-launching-bzflag-on-all-machines-on-the-network at work.

Photos at lca 2005…

Some of my progress can be seen at the xda-linux photo section.