Mats Lindh

While I initially thought I had gone crazy or were still dreaming, my fear was true – all my keyboard page navigation had stopped working in Firefox (3.6.3). I tried to move onto to the next by pressing space or page down, my hands trembled as I discovered that neither arrow keys or home / end keys worked. The friendly internet suggested that I should turn Caret Browsing (F7) off (.. so try that if you’re in this situation), but that just told me that I were turning Caret Browsing on (with a proper warning). No luck.

After a bit of tinkering I disabled all my add-ons (previously known as extensions), and voilá, everything worked as it were supposed to! Further problem hunting revealed the culprit: The Del.icio.us Bookmarks Add-on. Curse you, del.icio.us! Disabling the Add-on and re-enabling all the other addons solved the issue, and I’m now happily browsing the internet one page size at the time again.

After running into a need for a max iteration count on a foreach block tonight and seeing that several others have had the need during the years, I’ve created a simple patch to add max= as an attribute to the foreach block. I tried to search the archives for a reason why this hadn’t already been included, so feel free to ignore this patch if there are proper reasons why this isn’t available as an argument. There are cases where a simple break in the loop is more efficient than making a copy with array_slice if you need the same data several places but in different slice sizes.

The patch also contains three tests to test the max attribute.

The patch is available here: smarty.foreach.max.patch. The patch is against the current SVN trunk of 2010-08-08.

Example:

{foreach item=x from=[0,1,2,3,4,5,6,7,8,9] max=5}{$x}{/foreach}

Output:

01234

It’s that time of the year again, where I spend a few saturdays out in the woods riding my bike together with a couple of thousand other interesting people. Today it was Grenserittet (“Cross Country Ride”, from Strömstad in Sweden to Halden in Norway) which I also did in 2009 and 2008.

This year’s course had to have an emergency fix after 30mms of rain on Thursday made parts of the track almost disappear. It was quite a minor change, as there was an alternative road almost parallel to the original one.

After getting up at 06:30 this morning and travelling to my parents home, my dad and me left for Strömstad and my 09:55 start. It was supposed to rain at the start, but in the late hours of last night the weather prognosis changed and promised sun with a few clouds. Spot on! As we rolled out from Strömstad light clouds covered the sky, making the temperature just right for a day out on gravel roads and forest trails!

I decided to bring along two gel packs (100g each) and one energy bar – this proved to be just about right for the trip (in addition to two water bottles, with refill at the service stations at each 20km). I also ate a piece of banana at each of the service stations and downed a cup of sports drink. The energy bar was consumed in two rounds between 30km and 50km.

The number bibs that each rider attaches to his or her bike and back had changed this year. Instead of having the contestant number as the largest feature, the organizers had decided to go with printing the first name of the rider instead. This worked great! It made the spectators cheer for you by name and made it a lot easier to keep track of people you were riding with! As Per Øyvind (.. if I remember correctly) said after 30kms, “hey, it’s Mats again! We’ve been riding together since the start!”. Getting a name attached to a person made it a lot easier to remember that you had seen these people before, if they had raced past you a couple of minutes ago, etc. Great stuff.

Anyways! Today’s result:

3:41:37

(2009: 4:45:57, 2008: 4:47:04)

A new personal best with over one hour, and just four minutes behind the cut off point for the “wow, you were fast!”-prices. Awesome. I had hopes of getting below four hours, but this was beyond my expectations.

The bike has been washed, the clothes are ready for the washing maching (and yes, I did carry one small Norwegian forest worth of mud home) and I’m feeling my muscles rebuild while relaxing on the couch writing this post.

Now we’ll have to see what I can do in this year’s Birkebeinerrittet and start planning for next year!

After spending an hour trying to find out why my slave didn’t attempt to sync with my supermaster server (my domains were set to MASTER, axfr worked from the slave, etc..), I came across the fact that even though your server is authorative and will handle requests, it will not pretend to be an actual MASTER server unless master=yes is set in the configuration file.

One reload and suddenly all the domains synced magically.

Do check that one if you’re not seeing any notify-requests or any entries in your logfiles at all when updating or requesting a sync (through pdns_control).

After updating our debian installation on one of our servers we were left with a non-functioning Trac installation. An exception were thrown with a message about ClearSilver suddenly missing from our installation.

Solution: Debian packages ClearSilver ready for python:

.. and party like it’s 2010!

We’ve just installed rdiff-backup on some of our older RedHat Enterprise Linux 64-bit servers. We decided to install the .tar.gz-distributions and you can build your own rpms from these source packages (I won’t cover that here). There are a few pitfalls you’ll have to avoid.

First: librsync needs to be built with the 64-bit lib directory as the standard linkage, and needs to be compiled as a shared module.

To do this, provide configure with a few hints:

Then make and make install

Run ldconfig to be sure that your LD cache has been updated (make install should do this, but .. just to be sure.)

The “.. can not be used when making a shared object; recompile with -fPIC” error for librsync will occur if you build it without –enable-shared, while “/usr/lib/libpopt.so: could not read symbols: File in wrong format” will occur if you build the library with the standard 32 bit libraries.

After this rdiff-backup compiled as it should:

After rdiff-backup builds it python module and other small items, you might have to run ldconfig again (if you get “ImportError: librsync.so.1: cannot open shared object file: No such file or directory”, try this):

If you still get the above error, check that the directory where librsync was installed is present in either one of the files in /etc/ld.so.conf.d/ or in /etc/ld.so.conf itself. After adding the path to the library directory (which by default will be /usr/local/lib), run ldconfig again.

rdiff-backup should now (hopefully) work as expected.

During today’s hacking aboot I came across the above error from our Solr query library. The error indicates that some part of Tomcat was unable to parse the “GET / HTTP/1.1″ string – where it is unable to determine the “HTTP/1.1″ part. A problem like this could be introduced by having a space in the query string (and it not being escaped properly), so that the request would have been for “GET /?a=b c HTTP/1.1″. After running through both the working and non-working query through ngrep and wireshark, this did however not seem to be the problem. My spaces were properly escaped using plus signs (GET /?a=b+c HTTP/1.1).

There does however seem to be a problem (at least with our version of Tomcat – 6.0.20) which results in the +-s being resolved before the request is handed off to the code that attempts to parse the header, so even though it is properly escaped using “+”, it still barfs.

The solution:

Use %20 to escape spaces instead of + signs; simply adding str_replace(” “, “%20″, ..); in our query layer solved the problem.

After having a few issues with UTF-8 support in Emacs earlier (I .. well .. err .. use emacs as my .. mail editor.), I finally found a solution that works with both putty and gterm as my terminals.

The important settings I ended up using in my .emacs:

(prefer-coding-system       'utf-8)
(set-default-coding-systems 'utf-8)
(set-terminal-coding-system 'utf-8)
(set-keyboard-coding-system 'utf-8)

(setq x-select-request-type '(UTF8_STRING COMPOUND_TEXT TEXT STRING))

Archived for my own use at a later time.

Today: Using my own blog as a simple pastebin to remember a helper function I wrote while debugging a good selection of binary operations on integers in PHP. This will simply output the provided value as bit values (0 / 1). Wrap it in <pre>-s if you’re running it in a web context.

$len allows you do change how many bits it will print (starting from lsb – least significant bit), $blockSize adjust the amount of bits before throwing in a space.

Another error message from the attempt to move an existing MySQL installation to a new server, this time caused by the import of all the old users from the old server. debian (and Ubuntu) adds their own user to the server to be able to perform upgrades and other maintenance through automagical scripts. The password that debian (or Ubuntu) uses to connect to this user is stored in a file on the local file system: /etc/mysql/debian.cnf.

This file contains the current password for the debian-sys-maint user, and if you’re moving all your users to a new server, be sure to also get this password from the file on the old server and copy it into the file on the new server. I strongly suggest copying just the password and not the whole file, as there may be new settings added to the file since you last upgraded the old server.