The Old Monk

Some people have been saying that Firefox tries to emulate other browsers and be Windows-like in general. Some people have been saying that about Linux/Ubuntu as well. I don't know how correct they are and what they're based on, but there's one thing that comes in the category of being too smart and too user friendly which ends up annoying the regulars.

I was on my machine and wanted to run a remote instance on Firefox, with the display forwarded back to my machine. I had X forwarding over SSH and my DISPLAY enviroment variable all set up. But when I started 'firefox' on the remote commandline, it opened up an instance of firefox *locally*. WTF!!?

The fix to this is a 'MOZ_NO_REMOTE' env variable. Duh.

I got a new widescreen LCD for using with my Eee. Everything went on fine, but the default resolution of 1024x768 kinda sucked. The monitor (Acer AL1516W) supports a max of 1280x800, so I tried that, but I needed a custom modeline to get it working. The monitor specs say that it supports "1280x800@60Hz", but a lot of modeline generation tools don't support that odd widescreen resolution. This one does. The catch is the 60Hz - which is more like 59.91, which goes in as 59.73 in the textbox on that page. It does tell you the different values ("actually 59.91"), but you have to keep an eye. Another important thing is the monitor's 'Dot Clock' frequency. If you're exceeding that (and the tool will warn you if you are), it's most probably a mistake. Go re-read the specs of the monitor again.

FWIW, here's the modeline for the Acer AL1516W that I generated for the Eee :

"1280x800@59" 83.44 1280 1312 1624 1656 800 816 824 841

I'm writing a Perl interface to libtrackerclient (see the Tracker Project). The code will come out when it manages to do something - which should be soon, but I need a place to announce it and hold any comments that might come across. For the lack of a better option, I'd let this post be it.

Update : The code is at a stage where it's usable. The git repository is at http://repo.or.cz/w/LibTracker-Client-Perl.git. You can also grab the latest snapshot. The code is a lot of XS and some Perl. You would need libtrackerclient (and headers), glib-2.0 (and headers) and dbus-glib-1 (and headers) along with the obvious things like Perl headers and a C compiler.

There's always SCMBug, but you can cook your own Git-Bugzilla integration very easily. SCMBug's fine, but it's a lot of code if all you want is simple cross-linking between Git, Bugzilla and Trac (btw - GitPlugin for Trac would throw up an error unless you have at least *two* commits in your repository - talk about undocumented easter bugs!).

Anyhoo - here's what I want :
1. Git should disallow any commit where the commit message does not have a bug number.
2. Git should add a comment to the corresponding bug on a commit, mentioning the author, the Trac changeset link, the commit message and the list of files which changed.

And here's the code to do it. First, the post-receive hook :

#!/usr/bin/perl -w
use strict;

# A hook script which integrates with bugzilla. It looks for bug IDs in
# commit messages and adds the commit message as well as a link to the
# changeset as a comment on the bug.

# This program is released under the terms of the GNU General Public License
# version 2. A copy of the license may be obtained by emailing the author,
# or at http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt
#
# The absolute lack of warranty and other disclaimers as per the license
# apply.
#
# Copyright 2008, Devendra Gera. All rights reserved.
#
# Author : Devendra Gera 

### user configurable section

# The bugzilla has contains the server, username and password for the targeted
# bugzilla installation. There's NO 'http://' in the server line.
my $bugzilla = {
	server		=> "10.147.251.90/bugzilla",
	user		=> "demonuser",
	password	=> "daemonuserspassword",
};

# __PATH__ and __REVISION__ are replaced in $browser->{changeset} and
# $browser->{revision} to get the changeset and revision URLs respectively. 
my $browser = {
	changeset	=>
	"http://10.147.251.90/projname/changeset/__REVISION__",
	revision	=>
	"http://10.147.251.90/projname/browser/__PATH__?rev=__REVISION__",
};

# The bug_regex should extract the bug id from the commit message and place
# it in $1
my $bug_regex = 'bug #(\d+)';


##### End user configurable section

use WWW::Bugzilla;

my $input = <>;
chomp $input;

my ($oldrev, $newrev, $refname) = split /\s+/, $input;
my $commit_msg = `git-whatchanged $oldrev..$newrev`;

# prepare the changeset URL
my $changeset_url = $browser->{ changeset };
$changeset_url =~ s/__REVISION__/$newrev/g;

# author
my ($author) = ( $commit_msg =~ /^Author:\s+(.*)$/m );

# files
my @filelist = grep ( /^:/, split( /\n/, $commit_msg ) );

# prepare comment
$commit_msg =~ s/^.*?Date://s;	# eat everything till the Date: heder
$commit_msg =~ s/^.*?\n//m;	# eat the date line completely
$commit_msg =~ s/^:.*?$//mg;	# eat the file list from the msg.
chomp $commit_msg;
my ($bug_number) = ( $commit_msg =~ /$bug_regex/ );

my $comment = <<END_COMMENT;

------------------------------------
changeset $newrev [ $changeset_url ]
    by $author :

$commit_msg
------------------------------------

Files changed :
END_COMMENT

$comment .= join("", @filelist) . "\n";

my $bz = WWW::Bugzilla->new(
	server		=> $bugzilla->{ server },
	email		=> $bugzilla->{ user },
	password	=> $bugzilla->{ password },
	bug_number	=> $bug_number
);

die "cannot connect to bugzilla" unless defined $bz;

$bz->additional_comments( $comment );

$bz->commit;

And here's the update hook :

#!/usr/bin/perl -w
use strict;

my $refname = shift;
my $oldrev = shift;
my $newrev = shift;

my $commit_msg = `git-whatchanged $oldrev..$newrev`;

# check if the commit message contains a bug number
if($commit_msg !~ /bug #\d+/) {
	exit -1;
}

exit 0;

The TODO :
1. Push every configurable thing to git's config file and access it via git-config.
2. Code cleanups. One definition of the bug regex (which is hardcoded in the update for now).

edit : the here doc in the code was causing a problem with formatting, eating up some of the code. Fixed now.

WWW::Bugzilla was a great help in setting up git-bugzilla integration, but there's a small fix which needs to be applied before it would work with my Bugzilla 3 install.

The problem is that WWW::Mechanize selects the first form on a page by default, and WWW::Bugzilla fails in WWW::Mechanize while setting any field to be updated (with a 'no such field' or 'no field called comment' etc. messages). On my Bugzilla install, there's a small bug search form in the header which makes that happen.

The fix is a single line and has been emailed to the author. Here it is :

@@ -614,6 +614,7 @@
     my $mech = $self->{mech};
 
     if ($self->{bug_number}) {
+        $mech->form_name( "changeform" );
         foreach my $field ( keys %update_field_map ) {
             $mech->field( $update_field_map{$field}, $self->{$field} ) if defined($self->{$field});
             # handle special cases

There are various ways of managing multiple network profiles in Ubuntu, but I've never been a fan of NetworkManager. Commandlines work for me very well, and even there - multiple solutions exist with the help of packages like resolvconf etc. Here's my setup which is very Debian-ish and depends on this nice package called ifupdown.

First, there's the /etc/network/interfaces file :

# we always want the loopback
auto lo
iface lo inet loopback

# mappings
mapping eth0
  script /etc/network/map-scheme
  map dhcp eth0-dhcp
  map emergency eth0-emergency

mapping ath0
  script /etc/network/map-scheme
  map office ath0-office
  map home ath0-home

iface eth0-dhcp inet dhcp
  up iptables -F
  up lokkit -n -q --high --dhcp
  up /etc/init.d/lokkit restart

iface ath0-office inet dhcp
  wpa-driver madwifi
  wpa-conf /etc/wpa_supplicant/office.conf
  up iptables -F
  up lokkit -n -q --high --dhcp
  up /etc/init.d/lokkit restart

iface eth0-emergency inet static
  address 10.9.5.201
  gateway 10.9.4.1
  netmask 255.255.254.0
  up iptables -F
  up lokkit -q --high
  up echo nameserver 172.31.6.5 > /etc/resolv.conf
  up echo nameserver 203.197.12.30 >> /etc/resolv.conf

iface ath0-home inet dhcp
  wpa-driver madwifi
  wpa-conf /etc/wpa_supplicant/home.conf
  up iptables -F
  up lokkit -n -q --high --dhcp
  up /etc/init.d/lokkit restart

Notice the mappings section (and see 'man interfaces') - that allows me to say :

NETSCHEME="home" sudo ifup ath0

or

NETSCHEME="office" sudo ifup ath0

because the specified script (/etc/network/map-scheme) just looks up the NETSCHEME environment variable and spit out the correct mapping to go to. This thing, by the way, could be rigged to do arbitrarily complex tasks (look in /usr/share/doc/ifupdown/examples/ for sample scripts, including one which tries to ping some known IPs, and decides its location/profile based on successful pings - you could write one which looks for all known wireless SSIDs and then decide which profile to switch to). Here's my trivial script :

#!/usr/bin/perl -w
use strict;

my $scheme = $ENV{NETSCHEME} || "home";

while(<>) {
	if ( s/$scheme\s+// ) {
		print;
	}
}

The conf files in /etc/wpa_supplicant/* are of course wpa_supplicant configuration files. See 'man wpa_supplicant.conf' for details.

Btw, I'm taking a break. Jan 31 was my last day at work, and I haven't started looking for my next job yet. Heck, I don't even know what my next job will be like. The whole purpose of this thing is to explore certain areas and get some work done on some personal projects.

My Eee PC finally arrived. I played with the original Xandros/Asus interface for a day, and then moved to Ubuntu. My encrypted $HOME howto worked, but I kept /real_home on a SD card and added "noatime" to every FS mount.

One fallout is that I can't suspend - the SD card is a USB device and gets reset on suspend/resume. Also, the /var/log, /var/run, /var/tmp and /tmp are tmpfs filesystems. /var/cache/apt/ is a bind mount from the SD card to save the SSD from excessive writes.



Processing RAW images from my camera was a problem till I swapped the RAM with one of the modules from my Vostro 1400. GIMP works pretty smoothly now.

I use remind(short howto) to keep my calendar of events and reminders. Its a wonderful utility - and all commandline. I split up the birthdays, anniversaries, personally important days, and the usual stuff into different files, and include them in my ~/.reminders file. Here's what my .reminders looks like :

gera@gera-laptop:~$ cat .reminders 
include /home/gera/reminders/birthdays
include /home/gera/reminders/anniversaries
include /home/gera/reminders/impdates
include /home/gera/reminders/stuff

All this works well, except for a small issue. It takes too much time for me to add reminders for my day-to-day tasks. Firing up an editor and typing all that remind syntax is something that can be avoided. Also, it really hurts to look at the calendar to figure out fuzzy dates like "tomorrow", or "sat". I was planning to write this big Perl script which would do the heavy lifting for me. Instead, I found Date::Manip which already does the heavy lifting. It understands stuff like "tomorrow" and "sun". I just needed a small 'remindme' script then :

#!/usr/bin/perl -w
use strict;

use Date::Manip;
use Fcntl qw(:flock);

my $reminders = "$ENV{HOME}/reminders/stuff";

my $argstring = join (" ", @ARGV);
my ($when, $what);

(undef, $when, $what) = ($argstring =~ /^(on |)(.*?) to (.*)$/);
quit("what?") unless $what;
quit("when?") unless $when;

# form the line to be appended
my $date = ParseDate($when);
quit("cannot parse date") unless $date;

my $line = UnixDate($date, "REM %b %e %Y +1 MSG");
$line .= " $what %b.%\n";

# write in file

# open lock file
open LOCK, ">$reminders.lock" or quit("cannot open $reminders.lock : $!");
flock LOCK, LOCK_EX or quit("cannot obtain lock : $!");

# open data file, write and close data file
open REMINDERS, ">>$reminders" or quit("cannot open $reminders : $!");
print REMINDERS $line;
close REMINDERS;

# release locks
flock LOCK, LOCK_UN;
close LOCK;

exit (0);

sub quit
{
        my $msg = shift;
        print STDERR $msg, "\n";
        exit (-1);
}

Now, I can use it like this :

$ remindme on sat to eat everything I can
$ remindme tomorrow to pay the phone bill
$ remindme next week to think up of something useful to say
$ remindme next thursday to find something better to do

nifty, eh?

update: bugfixed the script. An extra space creeped up between the '+' and the '1'. Thanks to AmitU for pointing that out.
update 2: added the capability to get reminded n days in advance - a feature suggested by AmitU in the comments, but with a different syntax ("remindme next week to do this for 2 days"). Also, remindme's git repository and home page. The repository contains the bash-completion script as well.

I was introduced to GTD around a year ago, but wanted to manage mine using a commandline. I discovered todotxt.com and modified a todo.py to suit my needs (removed priorities, added some commands, bash-completion etc).

But I stopped doing it.

Because I had nothing to manage my "projects" (tasks with multiple action items). I maintained a list of projects out-of-band, as a directory structure, which required me to identify the next task for a project and move it to my todo list. Of course it didn't work!

So I wrote gtdo. gtdo has a similar interface - todo.py was the inspiration - but in addition to the contexts (marked by a '@'), it supports groups (or "projects" - marked by a '/'). So, you might have a project about starting using GNUcash. Of course, the first step is to install/set-up GNUcash. Adding your portfolio comes later. If you have both these items in your todo list, the second one does nothing but adds noise and makes the list longer. The answer is to add them in a group /gnucash. If there are multiple tasks in a group, only the first one is displayed - till its marked done. By default, new tasks are added at the end of the queue in a group, but may be added at a specific position.

An example would be better than the ramble above (gtdo being aliased to 't'):

$ t add /gnucash @online install gnucash
$ t add /frames @errands buy wood
$ t add /email @online set up spamassassin
$ t add /gnucash @online add portfolio to gnucash



# only the immediate next task is displayed when you 'ls'
$ t ls
1 : /gnucash @online install gnucash
2 : /frames @errands buy wood
3 : /email @online set up spamassassin



$ t ls @online
1 : /gnucash @online install gnucash
3 : /email @online set up spamassassin



# except when you specifically ask for a group
$ t ls /gnucash
1 : /gnucash @online install gnucash
4 : /gnucash @online add portfolio to gnucash



# well, we need to fix F::Q::IndiaMutual before we add our portfolio
# we'll try adding that as the second step in the /gnucash group
$ t add /gnucash.2 fix F::Q::IndiaMutual



$ t ls /gnucash
1 : /gnucash @online install gnucash
4 : /gnucash fix F::Q::IndiaMutual
5 : /gnucash @online add portfolio to gnucash

Comes with standard todo.sh style bash-completion. The Git repository is available at http://repo.or.cz/w/gtdo.git. You can obtain a tarball by clicking here.