So I decided to look at the code and see if I can add what I want. At first it seemed very easy to implement what I wanted so I started

It looked very very easy to implement rmfunc and zerofunc in the server, so I decided to contribute back my changes to the gearman project.

However, not everything is as easy as it seamed 1st Eric and Brian requested a test case which was to be in C with their test API. This was quite a challenge and I’m still not done with it

The 2nd thing seemed to be more complicated, but for me it was easier so I started with it. The problem was that, while it is no problem to remove functions which are executed as background jobs, its quite interesting when you try to remove function which has connected clients requesting it. When you remove currently requested function, there is no code that will notify connected clients that the function is no longer available, nor there is connection error sent to those clients. This breaks gearman communication in a lot of different ways.

So what I’m trying to achieve is add the functionality required to interrupt client communication with the server and send the proper error messages to the client. For me this is no easy job, but it seams that it is easier then the test cases.

I keep most of my books at home but I have usually at least one shelf at the office and rotate them, depending on the projects we are working on. Currently almost all of my Perl books are at the office.

One of the biggest problems I have is when I give some book to someone and I don’t remember… I have to find a good software which will keep track of that…

Here are some pictures of the books:

It was very interesting for me, to find that most(3/4) of the books I have already read. Currently I find it harder to buy new books since I already have most of the books I’m interested in.

However, the sad thing is that for the past 10 years I have only bought 6 books that were not IT related and currently I have only one of those

Instead of simply showing how can one use Git, this book describes how one should think in order to use Git. The comprehensive explanation of git’s internal structure in the beginning of the 4th chapter may seam as a little too much for the novice readers but it actually helps you understand all of the complicated logic which is behind this great software. Now when I thing about branching, merging or rebaseing I really know what’s going on. And all of this knowledge helps me solve problems that I have never managed to solve the past. Until now, I have been using best practices to work with Git without actually understanding why these were “the best” practices. In the book I found not only technical information about the software, but also a lot of information about how to manage a project, the right way.

I advice everyone to read this book. You will fill enlitened

And today while finalizing the MySQL Resource Agent for Heartbeat I have installed gitweb and I’ll try to add all of my contributions there.

The only problem yesterday was that we ran out of beer

First of all you should have to know that I setup the machine to be working with postfix + mysql + postfixadmin + dovecot. So the first step I took was to alter the database and add user ids there:


ALTER TABLE mailbox ADD COLUMN uid int NOT NULL AUTO_INCREMENT AFTER active, ADD KEY (uid);


Since on the machine there are already a lot of UIDs allocated from 0 to 1000 I decided that I will use UIDs over 30000 for this setup. But since the machine was in use for a week now, the above query populated the uid column with values. So what you do is, select the last UID from the table and update the AUTO_INCREMENT counter to the value you have + 30000. Here is how you could do it:


ALTER TABLE mailbox AUTO_INCREMENT=30173;
UPDATE mailbox SET uid=uid+30000;


Ok, so we have updated the database and we have the new UIDs that we have to use on the machine. The next step is to update the UIDs on the filesystem, so you enter your mail storage dir(mine is /var/vmail) and run this to fix the permissions:

mysql -e 'SELECT uid,maildir FROM mailbox' postfix|while read uid dir; do chown -R $uid $dir; done

The following steps are configurations for postfix and dovecot.

Since the current configuration for postfix was with static UID/GID maps for all users, now I had to update that. In the main.cf you will usually find these lines:

virtual_uid_maps = static:110
virtual_gid_maps = static:110

These are the static uid/gid maps. So we change ONLY the UID maps to:

virtual_uid_maps = proxy:mysql:/etc/postfix/mysql-virtual-uid-maps.cf


After you have done this you have to create the uid-maps.cf…:

user = postfix
password = *********
dbname = postfix
hosts = localhost
query = SELECT uid FROM mailbox WHERE username='%s' AND active = true

Now restart postfix and you have finished with it…

So what we have left to do is fix dovecot configuration:

in the protocol imap section you have to add this line:
mail_plugins = quota imap_quota
In the protocol pop3 section you have to add this line:
mail_plugins = quota
Then in the plugin section you have to add this line:
quota = fs:user

The last change is to the user_query for dovecot. You have to change this:
user_query = SELECT CONCAT('/var/vmail/',maildir) AS home, '110' AS uid, '110' AS gid, CONCAT('maildir:',CONCAT('/var/vmail/',maildir)) AS mail, CONCAT('maildir:storage=', ROUND( mailbox.quota / 1024 ) ) AS quota_rule FROM mailbox WHERE username = '%u'

To that:
user_query = SELECT CONCAT('/var/vmail/',maildir) AS home, uid, '110' AS gid, CONCAT('maildir:',CONCAT('/var/vmail/',maildir)) AS mail, CONCAT('maildir:storage=', ROUND( mailbox.quota / 1024 ) ) AS quota_rule FROM mailbox WHERE username = '%u'

Now after restart of dovecot you have everything setup and running.

And some plus is the automated quota handling. By adding one simple line to cron you can update the fs quota for all users:
mysql -e 'SELECT uid,ROUND(quota/1024),ROUND(quota/1024),"0","0" FROM mailbox' postfix|setquota -B /

Now you control the quota for all these users from the postfixadmin panel

Quite nice and quite easy. It took me 2hours to read all the documentation for that and to implement it.

• Advanced Programing in the Unix Environment
• Unix Network Programing Volumes 1 and 2

I think that these books are the bibles of network programing and they should be a must read for any C developer.

I have also ordered these two:

• Myths of Security
• The Art of Lean Software Development

I’m pretty excited about the Unix Network programing volume 1 since it is third edition and I have read only the second. In the third they cover the SCTP which is a very nice protocol. I actually implemented SCTP in OpenVPN and the book will help me understand just how many mistakes I have made in my implementation

I just found one initiative which asks every Bulgarian citizen to act and call all those who voted for this madness and try to make them vote against. I will surely make my 100 calls! Here is the list of all phone numbers:

http://jackie.hopto.org/blog/(Bulgarian)

I’m thinking of putting the code online, but since it is a really bad written Perl code for now I’ll save my self the embarrassment