FOSDEM 2013 is over and it's time to look what interesting I have seen there on Saturday. First of all the most important for me is to meet people. As usual, I came with SUSE folks, but it's not that unusual to meet people from company where you work :-). I've met some current and former phpMyAdmin developers and surprisingly I've met few Weblate users or people who consider using it on their project. This gave me some important feedback and one of first thing you will see in near future is remade Weblate website to give more information about some of it's unique features. As for the talks, I think I've managed to visit quite lot of them. How we made the Jenkins community explained some ways Jenkins has used to build good community - mostly focused on extensibility of the code and having everything as an extension, but with some focus on social things as well (and important thing that with Git people are not that motivated to join the team). Better software through user research was about various way to gather information of what your users hate on the software. It was pretty interesting, though many of that can not easily be used on small scale free software product. OSS code goes in and never comes out talk focused about licensing issues of various software as a service platforms. As I've never used Amazon cloud or such, it was quite surprising how these behave in relation to GPL and actually made me thing more about AGPL and attend related panel discussion later. An Integrated Localization Environment is Mozilla approach to online translation, quite different than anything we have before, but mostly for reasons which were explained later on Sunday talk on l20n. Maybe reverse ordering of these would make it easier to understand the motivation. Scale your Jenkins build pipeline automatically to minimize test time was not that useful as I thought - increasing test speed by buying EC2 instances and pushing part of the work to them is not something what will help me in near future. Trends in Open Source Security explained what is going on in distributions security, mostly focused on Redhat (but touching Debian as well). It has some interesting thoughts about sharing the information between vendors, so let's see if it will really work in future. QML s many faces showed some other ways to use QML besides using QtQuick. Some uses were quite interesting, though I'm not really fan of creating yet another buildsystem based on it. Panel Discussion: GNU Affero General Public License, version 3 was last thing I've visited on Sunday and it was really interesting to listen all that opinions on AGPL. Still I was not confirmed to consider switching to this license.

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Well I m back from LCA 2013 and what a great week it was. I learnt plenty of things over the week, including:

• Cloud computing into the government will be coming but will be hard to do in a significant way
• It wasn t just me that found the GTK 2 to 3 API change hard going
• OpenStack is the next cool kid on the block and there is a lot going on here
• Try out novaprova for testing C programs
• SELinux shouldnt slow my computer down and yes ill try it soon
• git-annex looks very interesting, I m just trying to find a use-case for it for me
• The development methods for Free Software have come a long way since a decade ago
• Test and release processes are important on large software projects
• Pretty much everyone I knew has changed companies, at least once.
• For multi-process communication, 0mq looks interesting

It was great to actually meet people who I ve known for years (over 10 for some) only as emails or irc chats as well. I ve not been to Mount Stromlo for almost as long and its somewhere I d like to visit again. Argh, the wordpress editor is still not fixed

WebAuth is the site-wide web authentication software that we use at Stanford. We're about to start another round of intensive development on multifactor authentication support, so I wanted to get a minor release out with the other things that have accumulated in the past month and a half. The main feature change in this release is to add support for another WebLogin configuration callback. This one is run whenever WebLogin is attempting to establish the user's identity and can return any identity it wishes, so it's available as a generic callback to determine identity information from the environment. The most likely use will be to inspect the results of client-side certificate authentication (which Apache puts in various environment variables) and interpret them in a site-specific way. Also in this release I refactored the WebLogin scripts so that they use FastCGI more correctly. The application objects are now instantiated only once and then reused for the lifetime of the FastCGI script, rather than torn down and set up for each new request. This is primarily of interest to those using the new features that require a memcached connection, since that connection will no longer be constantly set up and torn down, but it should help with speed in other situations. This is the riskiest change, since if I didn't get it exactly right it would be possible for information to leak from one request to the next. I've audited it fairly carefully, though, and think I've gotten everything. Finally, besides some documentation updates, I've switched the Perl build to Module::Build from ExtUtils::MakeMaker. This should mostly be transparent, but it means some additional Perl modules from CPAN will be required to build the distribution with --enable-webkdc for versions of Perl older than 5.10. (5.10 is fairly old, so I doubt this will be a serious issue.) You can get the latest release from the official WebAuth distribution site or from my WebAuth distribution pages.

Recently, I got to try out working in a couple different environments. Working in these environments helped me formalize some of the things that I like and some of the things I don't like. With these new environments I've come to realize my style of development. It's called penance driven development. It's called this because there are two important things:
1) It's better to ask forgiveness than for permissions
2) You need to be deserving of forgiveness.

So the concept is simple, whenever you break something, you first fix the symptom, then you improve the infrastructure so similar breaks should be harder to do. The cost of the penance doesn't have to be huge, but the penance has to be done, otherwise technical debt accumulates and people believe there is no downside to breaking things.

What needs to be improved depends on what is missing. For example, if an engineer broke a feature, but that feature didn't have a test, the penance should be to write a test. Even if the one that broke the feature isn't the owner or the one that wrote the feature. If someone breaks the build and no one noticed because the continuous build didn't email, the fix could be setting up the continuous build to email out build failures, or even better, run each change on a build bot before allowing commits.

I think I'll have to start a penance of the day blog/twitter stream.

I've been practicing this style of development for most of my career, and it's similar if less precise than the 5 whys . As mentioned in the The Lean Startup, the cost of the penance should be proportional to the cost of the break.

Next round of phpMyAdmin 4.0 translation status report is coming. So let's look at which translations are at 100% right now:

• Czech
• Dutch
• English (United Kingdom)
• Galician
• Greek
• Russian
• Spanish
• Turkish

There are also several languages which need just few strings to be complete:

• Danish
• Estonian
• French
• German
• Japanese
• Polish
• Portuguese (Brazil)
• Slovenian
• Swedish

As you can see, there is still lot of languages missing, this might be your opportunity to contribute to phpMyAdmin. Also you are welcome to translate phpMyAdmin 4.0 using translation server. If your language is already fully translated and you want to help as well, you can translate our documentation as well.

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Dear Lazyweb, can anyone recommend a good Thunderbird extension which allows for synchronizing the address book with Google mail? So far I tried Google Contacts, but something went wrong with the syncing and some contacts where deleted on both sides. To avoid this problem, one can use Google Contacts in read-only mode (it will only fetch contacts from Google, but never write to it) but then you have to import new Thunderbird contacts to Google mail manually. Google introduced CardDav in December 2012, which allows for syncing of contacts, but since Thunderbird s development is apparently on hold this is probably not gonna be supported out-of-the-box. There are some other extensions for Thunderbird, but since synchronization is hard and a lot more complicated than: replace newer version with older one I m looking for something mature and well tested. Before someone suggests it, I know Evolution has this feature built-in. I gave it a try last week and found so many other grave bugs with the calendar and newsgroups that Evolution is simply unfit for my needs. I really like Thunderbird and want to stick with it for a few more years until I have to look for something else. Yours truly, Basti

Over the last couple of weeks, I have been working on getting binary packages for [Varnish] modules built. In the current version, you need to have a built, unpacked source tree to build a module against. This is being fixed in the next version, but until then, I needed to provide this in the build environment somehow. RPMs were surprisingly easy, since our RPM build setup is much simpler and doesn't use mock/mach or other chroot-based tools. Just make a source RPM available and unpack + compile that. Debian packages on the other hand, they were not easy to get going. My first problem was to just get the Varnish source package into the chroot. I ended up making a directory in /var/lib/sbuild/build which is exposed as /build once sbuild runs. The other hard part was getting Varnish itself built. sbuild exposes two hooks that could work: a pre-build hook and a chroot-setup hook. Neither worked: Pre-build is called before the chroot is set up, so we can't build Varnish. Chroot-setup is run before the build-dependencies are installed and it runs as the user invoking sbuild, so it can't install packages. Sparc32 and similar architectures use the linux32 tool to set the personality before building packages. I ended up abusing this, so I set HOME to a temporary directory where I create a .sbuildrc which sets $build_env_cmnd to a script which in turns unpacks the Varnish source, builds it and then chains to dpkg-buildpackage. Of course, the build-dependencies for modules don't include all the build-dependencies for Varnish itself, so I have to extract those from the Varnish source package too. No source available at this point, mostly because it's beyond ugly. I'll see if I can get it cleaned up.

Finally, phpMyAdmin packages for Debian and Ubuntu do not lag much behind upstream. Today, I've prepared packages for yesterday released bug fix release 3.5.6. For Debian users, the package should be soon available in experimental (sorry no uploads to unstable during freeze). Ubuntu users, can use my phpMyAdmin PPA. After dozens of comments and no help offered, I've still decided to be nice to Ubuntu users and adjusted the package so that it should work on Lucid as well. The downside is that, unlike in Debian, the package includes bundled copy of many PHP and javascript libraries. PS: As soon as Debian is not frozen or 4.0 is officially released, I will start uploading 4.0 to experimental. My current bet is that 4.0 release will come earlier.

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Well, today was another day of sleeping, zoning, and having no brain for programming (and no willpower for that or exercise, which is even more frustrating), so you all get more musing about missions and work. Tomorrow, I will re-engage my normal schedule and turn the television off again, because seriously, two days of recovery should be enough even for a whole afternoon of meetings. Perhaps the best concept in the scrum methodology for agile project management is the concept of the product backlog and the product owner. For those who aren't familiar, a scrum project has, as one of its inputs, a prioritized list of stories that the team will implement. During each planning session (generally between once a week and once a month), the development team estimates and takes from the front of the product backlog the top-priority stories that can be completed during that period of time. The product owner is responsible for building the list of pending development stories based on business needs and keeping them sorted in priority order so that the work of the team follows the goals of the larger organization. But the product owner does not get to say how difficult the stories are; the development team estimates the stories, and the product owner may change order based on those estimates (to do simpler things earlier, for example). We've been doing scrum to some extent or another for quite some time now, and while there are a variety of things that I like about it, I think this is the best part. And I think it has very useful concepts for management in general. The product backlog is effectively a problem stream of the sort that I talked about in my last couple of posts. It's a set of problems that need to be solved, that matter to other people. And, if the team is doing scrum properly, the problems are presented in a form that describe a complete unit of desired functionality with its requirements and constraints, but without assuming any sort of implementation. The problem is the domain of the product owner; the solution is the domain of the development team. I am increasingly convinced that my quality of life at work, and that of many other people doing similar sorts of development and project work, would be drastically improved if managers considered this role the core of their jobs. (Ironically, at least in our initial experiences with scrum, it was quite rare for regular managers to be product owners; instead, individual line staff or project managers act as product owners. I think this speaks to how confused a lot of managers are about their roles in a technical development organization. This seems to be improving.) The core of the sort of work that I do is a combination of ongoing maintenance and solving new problems. Both of those can be viewed as a sequence of (possibly recurring) stories; I know this because that's largely how I do my own time management. Apart from HR and staffing, the core role of a manager is almost exactly what scrum calls "backlog grooming": communicating with everyone who has input into what their group is doing, finding out what their problems are, translating that into a list of things that the organization needs to have done, prioritizing them, breaking them into manageable chunks, ensuring they are fully specified and actionable (read: well-written stories), and communicating their completion back to other stakeholders (and then possibly iterating). This lept out at me when I started thinking about our larger strategic vision. That strategic vision is a sort of product backlog: a set of development stories (or, in this case, epics that would be broken down into a large number of smaller stories). But most strategic plans have glaring flaws if they're evaluated by the standards of scrum product backlogs. They're normally written as marketing statements and aimed at the clients or customers rather than at the staff. From the staff perspective, they're often hopelessly vague, not concrete, actionable epics. Often, they are almost entirely composed of grand, conceptual epics that any scrum team would immediately reject as too large and nebulous to even discuss. And often they're undefined but still scheduled: statements that the organization will definitely complete some underspecified thing within the next year or two. Scrum rightfully rejects any form of scheduling for unspecified stories and epics. Additional vagueness and sketchiness is tolerated the farther the story is from the current iteration, so they can be put into the future backlog, but scrum makes no guarantees about when they'll get done until they've been sized and you can apply a reasonable velocity estimate. If you want to put a date on something, you have to make it concrete. This is exactly the problem that I have with long-range strategic plans. We already know this about technology development: long-range strategic plans are feel-good guesses, half-truths, and lies that we tell other people because we're expected to do so, but which no one really believes. The chance that we can predict anything about the shape of projects and rate of delivery of those projects three years from now is laughable, and certainly none of the work that would be required to make real estimates has normally been done for those sorts of long-term strategic projects. There are a lot of scrum advocates who would go farther than I in asking for a complete revolution of how technical projects are planned. I'm not sure how realistic that is, or how well the whole scrum process would work when rolling up work across dozens, if not hundreds, of scrum-sized teams. But in the specific area of the role of managers in a development organization, I think we could learn a lot from this product backlog concept. Right now, there is a constant tension between managers who feel like they need to provide some sort of visionary leadership and guidance (the cult of Steve Jobs) and line staff who feel like managers don't understand enough about specific technology to lead or guide anything. But if you ask a technical developer whether, instead, it would be useful for managers to provide a well-structured, priority-ordered, and clean problem stream from the larger organization so that the developer can trust the problem stream (and not have to go talk to everyone themselves) but have control over the choice of implementation within the described constraints, I think you would find a great deal of enthusiasm. As a further bonus, scrum has a lot of advice about what that problem stream should look like. I think some of the story structuring is overblown (for example, I can't stand the story phrasing structures, the "AS A... I WANT TO... SO THAT..." shackles), but one thing it does correctly emphasize is the difference between problem and solution. The purpose of the story is to describe the outcome from the perspective of the person who will use the resulting technology. Describing the constraints on the solution, in terms of cost or integrations, is actively encouraged. Describing the implementation is verboten; it's up to the project team to choose the implementation that satisfies the constraints. If managers in general would pick up even that simple distinction, I think it would greatly improve the engagement, excitement, and joy that developers could take in their work. There's very little that's more frustrating than to be given an interesting problem in the guise of a half-designed solution and be told that one is not permitted to apply any of one's expertise in elegance, robustness, or durability to replacing the half-baked partial solution. Or even be allowed to know the actual motivating problem, instead of the half-digested form that the manager is willing to pass on.

This morning I gave a status report on SE Linux. The talk initially didn t go too well, I wasn t in the right mental state for it and I moved through the material too fast. Fortunately Casey Schaufler asked some really good questions which helped me to get back on track. The end result seemed reasonably good. Here s a summary of the things I discussed: Transaction hooks for RPM to support SE Linux operations. This supports signing packages to indicate their security status and preventing packages from overwriting other packages or executing scripts in the wrong context. There is also work to incorporate some of the features of that into dpkg for Debian. Some changes to libraries to allow faster booting. Systems with sysvinit and a HDD won t be affected but with systemd and SSD it makes a real difference. Mostly Red Hat s work. Filename transition rules to allow the initial context to be assigned based on file name were created in 2011 but are not starting to get used. When systemd is used for starting/stopping daemons some hacks such as run_init can be avoided. Fedora is making the best progress in this regard due to only supporting systemd while the support for other init systems will limit what we can do for Debian. This improves security by stopping terminal buffer insertion attacks while also improving reliability by giving the daemon the same inherited settings each time it s executed. Labelled NFS has been accepted as part of the NFSv4.2 specification. This is a big deal as labelled NFS work has been going for many years without hitting such a milestone in the past. ZFS and BTRFS support but we still need to consider management issues for such snapshot based filesystems. Filesystem snapshots have the potential to interact badly with relabelling if we don t develop code and sysadmin practices to deal with it properly. The most significant upstream focus of SE Linux development over the last year is SE Android. I hope that will result in more work on the X Access Controls for use on the desktop. During question time I also gave a 3 minute lightning talk description of SE Linux.

LCA 2013 [1] is starting so it seems like time to finish my write-up of LCA 2012. As usual it was a great conference, although I got sick immediately after getting there which reduced my ability to attend. Android A major unofficial theme of the conference was Android. Most delegates seemed to have Android phones, the Samsung Galaxy S and Galaxy Nexus seemed to be the most popular phones. Many delegates had two or more phones for development purposes. A large portion of the casual conversation at the conference concerned Android. There were a couple of really interesting talks about the Serval mesh networking project [2] which involves Android phones running in ad-hoc Wifi mode for long range communication without any official base station. Serval allows transferring messages, pictures, and voice calls. If you need to get longer range you can mount one phone in a convenient place and other phones will decide to use it as a relay there is no need to have a dedicated relay device (such as a mobile phone tower or Wifi access point). Serval is supposed to work with Wifi access points but due to Java not exposing some networking details to the higher levels of software the code that was available at the time of the conference didn t support networks other than a /24, which meant that the conference Wifi network didn t work with Serval. As an aside most people at the conference who installed Serval were using a development version that was newer than the version on the Android market. I can t remember what the extra features were though. Serval was designed for emergency situations, it can be installed on phones (and pushed to other phones via Wifi) in the field and allow communications when the infrastructure is broken. Also it s designed with some aim of circumventing censorship which among other things means that there are no facilities for tracking use. I think it would be really handy to be able to in some way track viewing of or interest in images that are transported via the mesh (maybe by something similar in concept to Google +1). Then in a crowd sourced environment people who take photos would be encouraged in their work by audience appreciation. One thing that interests me is the possibility of using Serval on a cruise ship. A cruise ship is an environment where mobile phone calls are unreasonably expensive, cabin phones aren t much use (who pays for a cruise and hangs out in their cabin?), and where there is usually a Wifi network installed. If a ship has a single bridged Wifi network that allows connecting to Wifi before authenticating for Internet access (which is probably the common case) then you could transport VOIP over that network without paying and without incurring any expense on the cruise company. One of the Serval developers assured me that this should be possible, of course a cruise ship with 3,000 passengers probably doesn t use a /24 for their Wifi so the current versions of Serval won t work At the geek my dinner event (a party where everyone brought $20 of food/drink which was cooked by volunteers) an artist showed me some art work that she created on her Samsung Galaxy Note (which was the biggest phone on sale at the time), it was very impressive. She recommended Picasso Mirror Draw, Sketch Free, Sketch Book Mobile Express, and Freenote as free graphical programs for Android. Samsung has a Noteworthy Project advertising campaign based on the artistic uses of the Galaxy Note which has some good videos of artists [3]. Chris Neugebauer and Paris Buttfield-Addison gave an informative and amusing talk about Android UI development (this link has the video) [4]. It s a pity that I missed seeing that one live but fortunately the video is of high quality. Accommodation As I ve become interested in Sociology I couldn t help but notice the pictures that accompanied the rules about cleaning the dormitory (which were displayed over the kitchen sink), it seems to imply that cleaning is only women s work. I wonder whether the people who created that poster deliberately chose pictures of women or whether they just chose the first available pictures from a collection of stock photos. Someone who was near my dorm room seemed to not realise how their alarm impacts other people. For the first two mornings I was woken repeatedly after 6AM by someone who was pressing the snooze button on their alarm. When sleeping in close proximity to other people the reasonable options involve some combination of having no loud alarm, immediately turning the alarm off and getting up (not pressing snooze to have it go off repeatedly), and setting the alarm for a time when almost everyone wants to get up (EG 1 hour before the first session). Networking Chris Neugebauer organised the Unprofessional Delegates Networking Session which was a great event. It was an event held at the same time as the Professional Delegates Networking Session with the difference being that you had to pay $5 for food and there was no free drink. A lot of great people attended the UPDNS so I m glad I don t pay for the PDNS. It seems that we won t have a UPDNS this year unfortunately. Conclusion LCA is always great fun and very educational. I recommend attending every year.

• [1] http://www.linux.conf.au/
• [2] http://developer.servalproject.org/site/
• [3] http://noteworthyproject.com/
• [4] http://chris.neugebauer.id.au/2012/01/25/lca2012-android-is-not-vi-user-experience-for-geeks/

This post is about the port bootstrap build ordering tool (naming suggestions welcome) which was started as a Debian Google Summer of Code project in 2012 and continued to be developed afterwards. Sources are available through gitorious. In the end of November 2012, I managed to put down an approximation algorithm to the feedback arc set problem which allowed to break the dependency graph into a directed acyclic graph with only few removed build dependencies. I wrote about this effort on our mailinglist but didnt mention it here because it was still too much of a proof-of-concept. Later, in January 2013, I mentioned the result of this algorithm in an email wookey and me wrote to debian-devel mailinglist. Many things happened since November 2012:

Processing pipeline instead of monolithic tools The tools I developed so far tried to accomplish everything by themselves, reusing functionality implemented in a central library. Therefor, if one wanted to try out even trivial new things, it mostly meant to hack some OCaml code. Pietro Abate suggested to instead develop smaller tools which could work independently of each other, would only execute one algorithm each and could easily be connected together in different ways to achieve different effects. This switch is now done and all functionality from the old tools is moved into a new toolset. The exchange format between the tools is either plain text files in deb822 control format (Packages/Sources files) or a dependency graph. The dependency graph is currently marshalled by OCaml but future versions should work with just passing a GraphML (an XML graph format) representation around. This new way of doing things seems close to the UNIX philosophy (each program does one thing well, data is stored as text, every program is a filter). For example the deb822 control output can easily be manipulated using grep-dctrl(1) and there exist many tools which can read, analyze and manipulate GraphML. It is a big improvement over the old, monolithic tools which did not allow to manipulate any intermediate result by external, existing tools. Currently, a shell script (native.sh) will execute all tools in a meaningful order, connecting them together correctly. The same tools will be used for a future cross.sh but they will be connected differently. I wrote about a first proposal of what the individual tools should do and how they should be connected in this email from which I also linked a confusing overview of the pipeline. This overview has recently been improved to be even more confusing and the current version of the lower half (the native part) now looks like this: Solid arrows represent a flow of binary packages, dottend arrows represent a flow of source packages, ovals represent a set of packages, boxes with rounded corners represent set operations, rectangular boxes represent filters. There is only one input to a filter, which is the arrow connected to the top of the box. Outgoing arrows from the bottom represent the filtered input. Ingoing arrows to either side are arguments to the filter and control how the filter behaves depending on the algorithm. I will explain this better once the pipeline proved to be less in flux. The pipeline is currently executed like this by native.sh.

Two new ways to break dependency cycles have been discovered So far, we knew of three ways to formally break dependency cycles:

• remove build dependencies through build profiles
• find out that the build dependency is only used to build arch:all packages and therefor put it into Build-Depends-Indep
• cross compile some source packages

Two new methods can be added to the above:

• if a dependency relationship is not strong (pdf), then a different installationset can be chosen
• if a depended upon package is Multi-Arch:foreign then a binary package of an existing architecture might be able to satisfy the dependency.

Dependency graph definition changed Back in September when I was visiting irill, Pietro found a flaw in how the dependency graph used to be generated. He supplied a new definition of the dependency graph which does away with the problem he found. After fixing some small issues with his code, I changed all the existing algorithms to use the new graph definition. The old graph is as of today removed from the repository. Thanks to Pietro for supplying the new graph definition - I must still admit that my OCaml foo is not strong enough to have come up with his code.

Added complexity for profile built source packages As mentioned in the introduction, wookey and me addressed the debian-devel list with a proposal on necessary changes for an automated bootstrapping of Debian. During the discussiong, two important things came up which are to be considered by the dependency graph algorithms:

• profile built source packages may not create all binary packages
• profile built source packages may need additional build dependencies

Both things make it necessary to alter the dependency graph during the generation of a feedback arc set and feedback vertex set beyond the simple removal of edges. Luckily, the developed approximation algorithms can be extended to support such changes in the graph.

Different feedback arc set algorithms The initially developed feedback arc set algorithm is well suited to discover build dependency edges which should be dropped. It performs far worse when creating the final build order because it only considers edges by itself and not how many edges of a source package can be dropped by profile building it. The adjusted algorithm for generating a build order is more of a feedback vertex set algorithm because instead of greedily finding the edge with most cycles through it, it greedily finds the source package which would break most cycles if it was profile built.

Generating a build order with less profile built source packages After implementing all the features above I now feel more confident to publish the current status of the tools to a wider audience. The following test shows a run of the aforementioned ./native.sh shell script. Its final output is a list of source packages which have to be profile built and a build order. Using the resulting build order, starting from a minimal build system (essential:yes, build-essential and debhelper), all source packages will be compiled which are needed to compile all binary packages in the system. The result will therefor be a list of source and binary packages which fulfill the following property:

• all binary packages can be built from the available source packages
• all source packages can be built with the available binary packages

I called this a "reduceded distribution" in earlier posts. The interesting property of this specific selection is, that it contains the biggest problem set of Debian when bootstrapping it: a 900 to 1000 nodes big strongly connected component. Here is a visualization of the problem: Source packages do not yet come with build profiles and the cross build situation can not yet be analyzed, so the following assumptions were made:

• the minimal build system can be cross compiled from nothing
• the reduced build dependencies harvested from Gentoo and supplied by Daniel Schepler, Patrick McDermott, Thorsten Glaser and Wookey are correct
• the current list of weak build dependencies can be dropped from any source package
• even when profile built, all source packages build all binary packages
• the 14 forcefully broken build dependencies do not significantly change the output in real life

The last point is about 14 build dependencies which were decided to be broken by the feedback arc set algorithm but for which other data sources did not indicate that they are actually breakable. Those 14 are dynamically generated by native.sh. If above assumptions should not be too far from the actual situation, then not more than 73 source packages have to be modified to bootstrap a reduced distribution. This reduced distribution even includes dependency-wise "big" packages like webkit, metacity, iceweasel, network-manager, tracker, gnome-panel, evolution-data-server, kde-runtime, libav and nautilus. By changing one line in native.sh one could easily develop a build order which generates gnome-desktop or really any given (meta-)package selection. All of native.sh takes only 80 seconds to execute on my system (Core i5, 2.5 GHz, singlethreaded). Here is the final build order which creates 2044 binary packages from 613 source packages.

1. nspr, libio-pty-perl, libmcrypt, unzip, libdbi-perl, cdparanoia, libelf, c-ares, liblocale-gettext-perl, libibverbs, numactl, ilmbase, tbb, check, libogg, libatomic-ops, libnl($), orc($), libaio, tcl8.4, kmod, libgsm, lame, opencore-amr, tcl8.5, exuberant-ctags, mhash, libtext-iconv-perl, libutempter, pciutils, gperf, hspell, recode, tcp-wrappers, fdupes, chrpath, libbsd, zip, procps, wireless-tools, cpufrequtils, ed, libjpeg8, hesiod, pax, less, dietlibc, netkit-telnet, psmisc, docbook-to-man, libhtml-parser-perl, libonig, opensp($), libterm-size-perl, linux86, libxmltok, db-defaults, java-common, sharutils, libgpg-error, hardening-wrapper, cvsps, p11-kit, libyaml, diffstat, m4
2. openexr, enca, help2man, speex, libvorbis, libid3tag, patch, openjade1.3, openjade, expat, fakeroot, libgcrypt11($), ustr, sysvinit, netcat, libirman, html2text, libmad, pth, clucene-core, libdaemon($), texinfo, popt, net-tools, tar, libsigsegv, gmp, patchutils($), dirac, cunit, bridge-utils, expect, libgc, nettle, elfutils, jade, bison
3. sed, indent, findutils, fastjar, cpio, chicken, bzip2, aspell, realpath, dctrl-tools, rsync, ctdb, pkg-config($), libarchive, gpgme1.0, exempi, pump, re2c, klibc, gzip, gawk, flex-old, original-awk, mawk, libtasn1-3($), flex($), libtool
4. libcap2, mksh, readline6, libcdio, libpipeline, libcroco, schroedinger, desktop-file-utils, eina, fribidi, libusb, binfmt-support, silgraphite2.0, atk1.0($), perl, gnutls26($), netcat-openbsd, ossp-uuid, gsl, libnfnetlink, sg3-utils, jbigkit, lua5.1, unixodbc, sqlite, wayland, radvd, open-iscsi, libpcap, linux-atm, gdbm, id3lib3.8.3, vo-aacenc, vo-amrwbenc, fam, faad2, hunspell, dpkg, tslib, libart-lgpl, libidl, dh-exec, giflib, openslp-dfsg, ppl($), xutils-dev, blcr, bc, time, libdatrie, libpthread-stubs, guile-1.8, libev, attr, libsigc++-2.0, pixman, libpng, libssh2, sqlite3, acpica-unix, acl, a52dec
5. json-c, cloog-ppl, libverto, glibmm2.4, rtmpdump, libdbd-sqlite3-perl, nss, freetds, slang2, libpciaccess, iptables, e2fsprogs, libnetfilter-conntrack, bash, libthai, python2.6($), libice($), libpaper, libfontenc($), libxau, libxdmcp($), openldap($), cyrus-sasl2($), openssl, python2.7($)
6. psutils, libevent, stunnel4, libnet-ssleay-perl, libffi, readline5, file, libvoikko, gamin, libieee1284, build-essential, libcap-ng($), lcms($), keyutils, libxml2, libxml++2.6, gcc-4.6($), binutils, dbus($), libsm($), libxslt, doxygen($)
7. liblqr, rarian, xmlto, policykit-1($), libxml-parser-perl, tdb, devscripts, eet, libasyncns, libusbx, icu, linux, libmng, shadow, xmlstarlet, tidy, gavl, flac, dbus-glib($), libxcb, apr, krb5, alsa-lib
8. usbutils, enchant, neon27, uw-imap, libsndfile, yasm, xcb-util, gconf($), shared-mime-info($), audiofile, ijs($), jbig2dec, libx11($)
9. esound, freetype, libxkbfile, xvidcore, xcb-util-image, udev($), libxfixes, libxext($), libxt, libxrender
10. tk8.4, startup-notification, libatasmart, fontconfig, libxp, libdmx, libvdpau, libdrm, libxres, directfb, libxv, libxxf86dga, libxxf86vm, pcsc-lite, libxss, libxcomposite, libxcursor, libxdamage, libxi($), libxinerama, libxrandr, libxmu($), libxpm, libxfont($)
11. xfonts-utils, libxvmc, xauth, libxtst($), libxaw($)
12. pmake, corosync, x11-xserver-utils, x11-xkb-utils, coreutils, xft, nas, cairo
13. libedit, cairomm, tk8.5, openais, pango1.0($)
14. ocaml, blt, ruby1.8, firebird2.5, heimdal, lvm2($)
15. cvs($), python-stdlib-extensions, parted, llvm-2.9, ruby1.9.1, findlib, qt4-x11($)
16. xen, mesa, audit($), avahi($)
17. x11-utils, xorg-server, freeglut, libva
18. jasper, tiff3, python3.2($)
19. openjpeg, qt-assistant-compat, v4l-utils, qca2, jinja2, markupsafe, lcms2, sip4, imlib2, netpbm-free, cracklib2, cups($), postgresql-9.1
20. py3cairo, pycairo, pam, libgnomecups, gobject-introspection($)
21. gdk-pixbuf, libgnomeprint, gnome-menus, gsettings-desktop-schemas, pangomm, consolekit, vala-0.16($), colord($), atkmm1.6
22. libgee, gtk+3.0($), gtk+2.0($)
23. gtkmm2.4, poppler($), openssh, libglade2, libiodbc2, gcr($), libwmf, systemd($), gcj-4.7, java-atk-wrapper($)
24. torque, ecj($), vala-0.14, gnome-keyring($), gcc-defaults, gnome-vfs($)
25. libidn, libgnome-keyring($), openmpi
26. mpi-defaults, dnsmasq, wget, lynx-cur, ghostscript, curl
27. fftw3, gnupg, libquvi, xmlrpc-c, raptor, liboauth, groff, fftw, boost1.49, apt
28. boost-defaults, libsamplerate, cmake, python-apt
29. qjson, qtzeitgeist, libssh, qimageblitz, pkg-kde-tools, libical, dwarves-dfsg, automoc, attica, yajl, source-highlight, pygobject, pygobject-2, mysql-5.5($)
30. libdbd-mysql-perl, polkit-qt-1, libdbusmenu-qt, raptor2, dbus-python, apr-util
31. rasqal, serf, subversion($), apache2
32. git, redland
33. xz-utils, util-linux, rpm, man-db, make-dfsg, libvisual, cryptsetup, libgd2, gstreamer0.10
34. mscgen, texlive-bin
35. dvipng, luatex
36. libconfig, transfig, augeas, blas, libcaca, autogen, libdbi, linuxdoc-tools, gdb, gpm
37. ncurses, python-numpy($), rrdtool, w3m, iproute, gcc-4.7, libtheora($), gcc-4.4
38. libraw1394, base-passwd, lm-sensors, netcf, eglibc, gst-plugins-base0.10
39. libiec61883, qtwebkit, libvirt, libdc1394-22, net-snmp, jack-audio-connection-kit($), bluez
40. redhat-cluster, gvfs($), pulseaudio($)
41. phonon, libsdl1.2, openjdk-6($)
42. phonon-backend-gstreamer($), gettext, libbluray, db, swi-prolog, qdbm, swig2.0($)
43. highlight, libselinux, talloc, libhdate, libftdi, libplist, python-qt4, libprelude, libsemanage, php5
44. samba, usbmuxd, libvpx, lirc, bsdmainutils, libiptcdata, libgtop2, libgsf, telepathy-glib, libwnck3, libnotify, libunique3, gnome-desktop3, gmime, glib2.0, json-glib, libgnomecanvas, libcanberra, orbit2, udisks, d-conf, libgusb
45. libgnomeprintui, libimobiledevice, nautilus($), libbonobo, librsvg
46. evas, wxwidgets2.8, upower, gnome-disk-utility, libgnome
47. ecore, libbonoboui
48. libgnomeui
49. graphviz
50. exiv2, libexif, lapack, soprano, libnl3, dbus-c++
51. atlas, libffado, graphicsmagick, libgphoto2, network-manager
52. pygtk, jackd2, sane-backends, djvulibre
53. libav($), gpac($), ntrack, python-imaging, imagemagick, dia
54. x264($), matplotlib, iceweasel
55. strigi, opencv, libproxy($), ffms2
56. kde4libs, frei0r, glib-networking
57. kde-baseapps, kate, libsoup2.4
58. geoclue, kde-runtime, totem-pl-parser, libgweather, librest, libgdata
59. webkit
60. zenity, gnome-online-accounts
61. metacity, evolution-data-server
62. gnome-panel
63. tracker

The final recompilation of profile built source packages is omitted. Source packages marked with a ($) are selected to be profile built. All source packages listed in the same line can be built in parallel as they do not depend upon each other. This order looks convincing as it first compiles a multitude of source packages which have no or only few build dependencies lacking. Later steps allow fewer source packages to be compiled in parallel. The amount of needed build dependencies is highest in the source packages that are built last.

My 1Tb laptop drive started misbehaving a few weeks ago, just spending a lot of time spinning when it should have been reading frequently changed files (like the browser cache). I was tempted to blame the browser at that point as no other packages appeared affected.

Wednesday night, a routine package upgrade on unstable brought in a bunch of qt4 updates which I wanted and a virtual box update that I didn't see much point in delaying ... 15 minutes later I couldn't work out why the virtualbox dkms task was still running, spotted it spinning in depmod and found some alarming messages in dmesg about short reads and errors reading from the hard drive. Hmm. The hard drive was out of control at this point, it quickly became apparent that no disc access was going to be possible and I couldn't get to a terminal to kill the current tasks, so I killed the power. The fsck which followed reboot showed more of the errors I'd seen in dmesg and fell back to the manual intervention stage. A few hours of confirming attempts to fix the errors, fsck finally finished. A short amount of usage showed that although fsck had finished, the drive was not happy and was starting to give short reads on other parts of the filesystem, resulting in ~40% of the filesystem appearing to be read-only when the rest was read-write. Somehow, I didn't think this was a welcome feature as the areas affected appeared to be quite random.

The drive in question was a replacement for the original 300Gb drive supplied with the ThinkPad, so a quick bit of switching of drives into a caddy and I could rsync my data off the large drive onto the smaller one. The rsync itself took a lot longer than it should have done because it got lots of short reads too. (Principally in /lib/modules/3.2.0-4/ and in the browser cache directories which had been the original symptom as well as most other places where one could have expected processes to have open files when the drive failed).

Now the 1Tb drive was a pig to fit into the Thinkpad originally because it was too big for the bay but I fitted it anyway. Yes, that was probably a mistake. It certainly meant that in order to fit it I had to not put the drive into the useful caddy provided by Lenovo which makes removal of the drive simple. Indeed the drive was wedged into the bay so tightly that it wasn't going to come out with normal levels of persuasion. This probably contributed to the failure of the drive, so live and learn.

With help from Andy Simpkins (it's always handy to have a hardware engineer on hand at times like this), the keyboard was lifted out, the case was dismantled and just enough room was made to get a screwdriver in behind the sata drive and lever it out of the bay. OK, rebuild laptop, put replacement drive into the caddy (because the smaller capacity drive is also a lot smaller in height than the 1Tb and therefore has plenty of clearance between it and the bay) and move on to the software recovery stage.

Hint: if this happens again, before turning off the broken system for the last time, just remember to download a recent Debian ISO to a USB stick - it saves having to ask someone else or find another machine to do the download. (Thanks Andy...)

OK, so after the usual complaints on reboot that there was no operating system, F12 got the boot order menu up and I was in Debian Installer Rescue Mode. Reinstalling grub failed initially for a few reasons:

1. 
   I'd deliberately not copied /dev /proc and /sys from the old harddrive but I'd also forgotten to create empty ones on the new drive...
2. /etc/fstab helpfully referred to / as a UUID which no longer applied, so that had to be edited
3. grub was confused and couldn't find the root filesystem

A few iterations later, I had a working /dev directory inside the /target chroot, bind mounted from the /dev outside the chroot, I was able to mount proc and sys, so grub was finally happy to reinstall itself and then update the initramfs setup for the new drive.

Reboot, another fsck, all appeared well. I was able to login via the terminal but not in X. Hmmm. Stop xdm, startx manually from the terminal, problems with /tmp/ - permission denied. Oops. Yes, it does help to create /tmp with the right permissions....

The final stage was to complete the dpkg --configure -a from the original failure. I've yet to reinstall the 3.2.0-4 kernel, so I'm back on 3.2.0-3 but that's OK.

So now I'm back on the original drive, albeit temporarily without any swap whatsoever (because I didn't partition the replacement drive to create /dev/sda5 before doing the copy) and now I remember the second reason I wanted to replace the original drive with the 1Tb drive - the original drive is as NOISY as hell. The whole edge of the laptop vibrates constantly, to the point that I can feel the vibration under the keys as I type. It's not that the drive is loose in the bay, it's just a constant vibration.

But, I have kept all my data and I have a usable laptop for the BSP this weekend. I will be looking at an SSD drive to replace this one though and having also found my old Acer laptop with power supply, I can now reference this entry when I transfer the system a second time.

I ve been trying to tidy up my Mako templates within my Turbogears 2 project. As part of that I was looking at some of them that are quickstarted including one which is the About page. What was curious was there was all this CSS work all done already for you, including icons. Digging further I found out that one of the many projects Turbogears takes in, is Bootstrap. It s website describes Bootstrap as Sleek, intuitive, and powerful front-end framework for faster and easier web development. but what it means to me is a bunch of guys who understand HTML and CSS way better than me have made it easy for me to build a decent web application. While the framework won t suit everyone s tastes, it makes a lot of the formatting decisions so much easier. The thing is, in all the Turbogears documentation I have read I ve not heard it mentioned. Not sure why, its pretty awesome (not SQLAlchemy awesome but not many things are).

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For some time I ve been wondering how the wire size for power supplies limits the power. So I ve done some quick calculations to determine if it s a problem. The first type that is of interest are the Inverters that are used to convert 12VDC to 240VAC (mains power) to allow electric devices to be operated in a car. I ve seen some reports from dissatisfied user about Inverters not supplying as much power as expected and I ve had problems with my 150W Inverter not always supplying my Thinkpad (which definitely doesn t draw 150W). The second type is phone chargers as charging a phone in a reasonable amount of time is always a problem. Inverter Rating Fine Print vs Laptop PSU My Thinkpad Power Supply claims Efficiency Level IV which according to the US EPA document describing the efficiency marking protocol for external power supplies [1] means that it is at least 85% efficient when supplying 50W+. The peak output of the PSU is 4.5A at 20V which is 90W peak output, 90/0.85 == 106W power drawn. One would hope that wouldn t be a problem from a 150W PSU. But the fine print on the PSU says that it can provide 110W continuously and 150W for 10 minutes. So according to my calculations I m within 4W of overloading the PSU if my Thinkpad uses full power. It also says that it is designed for 13.8V input. I have no idea how the performance of the Inverter changes as the supply Voltage changes between the 12.6V that a 6 cell lead-acid battery is designed to provide and the 13.8V charge from the car alternator. But I have had occasions when my Inverter stopped working correctly presumably due to being unable to supply as much current as my Thinkpad draws. As an aside I measured the Voltage in my car (with the engine off) at 12.85V from the cigarette lighter socket and 13.02V directly from the battery. I wonder if there is some sort of overload protection on the cigarette lighter which has a side effect of reducing the Voltage. Resistance in wires reduces the Voltage, but all Voltage meters are designed to have a high resistance to prevent that from being an issue. If anyone has an explanation for the 0.17Volt drop then please write a comment! Can a Car Provide 130W from the Cigarette Lighter socket? If the Inverter is also 85% efficient (and it might be less as it has no indication of efficiency on the box) then when supplying 110W it would draw 110/0.85 == 129.4W (I ll round it up to 130W). The power in Watts is equal to the Voltage multiplied by the current in Amps (W=V*I). Therefore I=W/V so if the car battery was at 12.85V then 130W/12.85V == 10.12A will flow. The current that goes through a circuit is equal to the Voltage divided by the resistance (see the Wikipedia page on Ohm s law for more information). This also means that the resistance equals the Voltage divided by the current. 12.85V/10.12A == 1.27 Ohms. Note that this is the resistance of the entire circuit, all the wires going to the battery, the circuitry inside the Inverter, and the internal resistance of the battery. The Inverter s cable is 1M long (2 meters of wire) and each wire is about 3.5mm in diameter including the insulation which means that the copper wire is probably equivalent to a single core conductor that is about 1mm in diameter. According to one of the online guides to resistance [2] wire that is 1.02mm in diameter will have a resistance of 0.02 Ohms per meter which gives a resistance of 0.04 Ohms. 0.04 Ohms is 3% of the total resistance of the circuit which doesn t seem like it will be a real problem. In practice I ve noticed that the connector gets extremely hot when it s in use while the cable doesn t get warm enough to notice. I suspect that the quality of the connector limits the power that is available but I don t have an easy way of measuring this. Inverters that are rated at 300W are designed to attach directly to the battery. An Inverter that is rated at 300W would draw 300W/0.85 == 352W from the battery. That needs 352W/13.02V == 27.04A and therefore a circuit resistance of 13.02V/27.04A == 0.48 Ohms total resistance. I wonder whether dirt on the battery terminals would give a significant portion of that. Phone Charging I ve also been wondering about why mobile phones take so long to charge, and now I ve finally done the calculations. The latest standard for mobile phones is to use USB for charging. The Wikipedia page about USB says that the standard is for USB 2.0 to supply up to 500mA at 5V +-5%. That means 0.5A*5V == 2.5W +- 5%. If we assume that the internal power supply in a phone is also 85% efficient then that means 2.5*0.85 == 2.125W going to the battery. My Samsung Galaxy S3 has a battery which is rated at 7.98Wh. According to the Wikipedia page about Lithium Ion batteries the charge/discharge efficiency is 80% to 90% I ll assume that it s 85% for further calculations. If the battery in the phone is 85% efficient and the phone is doing nothing but charging then the charge time for a regular USB port would be 7.98Wh/0.85/2.125W == 4.42 hours (4 hours 25 minutes) of charge time. That probably means something closer to 5 hours to totally charge the phone while it s running. There are dedicated charging ports for USB which can supply up to 1.5A. The 3rd party charger which came with my phone was rated at 1A and would hopefully be capable of completely charging the phone in less than 3 hours (but in practice isn t). It s interesting to note that MacBooks expose the amount of current drawn from a USB port with a GUI, so it should be possible to measure a phone charge rate by connecting it to a MacBook (which is cheaper than cutting up a phone cable). My old Samsung Galaxy S has a battery which is rated at 5.55Wh, by the same calculations it would take slightly more than 3 hours to charge on a standard USB port or 1.5 hours on my newest USB charger. In practice it has never got anywhere close to that, I presume that the phone is designed to draw less than 500mA. Phone Cable Resistance The charger that came with my Galaxy S has a cable that is about 1.75M long, the cable is flat and measures just over 1mm thick and about 2mm wide. Presumably the wire is equivalent to a single core that s about 0.4mm in diameter thus giving it a resistance of about 0.134 Ohm per meter, or 1.75*2*0.134 == 0.469 Ohm for the cable. The charger is rated at 0.7A. To supply 0.7A at 5V the resistance would be 5V/0.7A == 7.143 Ohm so about 6.6% of the total resistance of the circuit would be in the wire from the charger to the phone. The charger that came with my Galaxy S3 has a round cable that s just over 3mm thick and about 90cm long. If each wire in the cable is equivalent to a solid wire that is 0.912mm in diameter then it would be 0.0264 Ohm per meter of wire or 0.9*2*0.0264 == 0.0475 Ohm. The total circuit resistance would be 5V/1A == 5 Ohm. So 0.0475 Ohm is less than 1% of the circuit resistance. Voltage Drop The Voltage across a part of a circuit is proportional to the resistance (see the Wikipedia page on Series and Parallel Circuits for a good explanation). Basically this means that if 1% of the resistance of a circuit is in the wire then 1% of the Voltage drop will also be in the wire, so if we have a 5V supply with my Galaxy S3 cable then each of the two wires in the cable will have a difference of about 0.025V between the ends and the phone will receive a supply of 4.95V, the difference isn t something that is worth worrying about. But the cable from my Galaxy S has a resistance equivalent to 6.6% of the circuit resistance which means that the theoretical charge time will be 6% longer than it might be or 6% more current will be drawn from the mains than should be needed. Conclusion The charger that came with my Samsung Galaxy S isn t much good. Wasting 6.6% of the power in the wire is unreasonable. Phones keep getting more power hungry and batteries keep getting larger. There are third party phone batteries and external batteries that are charged by USB which have more than twice the capacity of the stock phone batteries this means more than twice the charge time. This problem will keep getting worse. The problem of a phone in active use drawing more power than the charger can provide (and running out of battery while on the charger) seems likely to stay with us. So while an Android phone has the potential to be a great little embedded server it seems that hacking the power supply is going to be a required first step for realising that potential. The decision to make 5V the USB power standard was reasonable at the time as it was the voltage used for most things on the motherboard. The decision to use USB as the phone charging standard was also reasonable, it allows phones to be charged anywhere. The combination of those two decisions isn t good for the user. If a higher Voltage such as 12V was used then 5* the power could be supplied through the same wires at the same level of efficiency. It would be really good if cars came with built in Inverters and supplied 240VAC or 110VAC depending on the region they were manufactured for. It s becoming a fairly common feature to have a cigarette lighter port in the car boot as well as at least two ports inside the car. When a car has three sockets and only one device to actually light cigarettes (which I suspect is only provided to fill an empty socket) it s very obvious that people want to connect random devices. Also having USB charging ports inside the car would be a really good idea (one for each seat would be good for Ingress).

• [1] http://tinyurl.com/cd6jpcv
• [2] http://www.daycounter.com/Calculators/AWG.phtml

Recently I ve been doing my personal development SSH d into my personal laptop. I found that launchpadlib (which various projects use for release automation) was failing the gnome keyring API threw an error because the keyring was locked, and python-keyring didn t try to unlock it. I needed a workaround to be able to release stuff, and with a bit of digging and help from #launchpad, came up with this: mkdir ~/.cache/keyring
mkdir ~/.local/share/python_keyring
echo > ~/.local/share/python_keyring/keyringrc.cfg << EOF
[backend]
default-keyring=keyring.backend.UncryptedFileKeyring
keyring-path=/home/robertc/.cache/keyring/
EOF (There is already encryption in place, so I chose an uncrypted store read the keyring source to find other alternatives). With this done, I can now use lp-shell etc over SSH, for when I m not physically at my machine.

I did not realize how much I was missing this sort of heads-down programming time in my life until the last two days. I think the last time that I had this much fun with my job was when I was learning Java, and even that wasn't quite this much fun since it was a lot of experimentation rather than being directly productive in a language I know well. Here's a short list of modern Perl, Perl techniques, and interesting modules that I'd not had a reason to use before today:

• Profiling and Devel::NYTProf. What a lovely piece of software. I'm starting to like this trend towards useful developer tools dumping their output in HTML, particularly when many of them are this pretty. (Devel::Cover by way of Test::Strict also does this, and I've been making heavy use of it.)
• Memoize. I've known it existed for years, but I've never had a reason to use it. Memoizing str2time when doing log parsing cut the time by a quarter. (I'll probably write a hand-rolled date parser for the specific date format eventually, since str2time is really slow since it's so general, but wrapping Memoize around it takes five seconds.)
• Module::Build. I was staying away from this because of all the problems Debian had with embedded code copies, but it appears to not be doing that any more (or at least I can use it in a way that it doesn't). And it really is so much nicer than ExtUtils::MakeMaker. I will probably convert all of my packages over time, although I have to see what it's like for XS modules. ETA 2013-01-24: Gregor pointed out that I was confusing Module::Build with Module::Install. I feel silly now; I've been avoiding Module::Build solely because I've been confusing it with something else entirely!
• HTTP::BrowserDetect. This isn't a general piece of software, of course, but once again it was lovely to discover that CPAN already contained exactly the piece of software that I needed. I'm trying to produce a summary of what browsers our authenticated users use as part of a general software inventory, and this turned the nonsense that browsers send into exactly the sort of management-consumable classifications I needed.
• IO::Compress and IO::Uncompress. Yes, this is much nicer than what I used to have to do with Compress::Zlib. It's like people kept working on Perl while I've been using all the things I learned five years ago!

I still have tomorrow morning to continue focusing on this and will hopefully finish up the work to feed long time periods of logs into my analysis tool. And, even better, I have a log parsing framework that I really like and that I think will make any number of things easier in the long run. (Also, it has a remarkably thorough test suite. I love test-driven development. Although I haven't written comprehensive tests for the very final front-end piece, since generating sanitized log input to trigger all the cases is too much effort right at the moment.)

Weblate 1.4 has been released today. It comes with lot of improvements, especially in configurability, admin interface and usability. Full list of changes for 1.4:

• Fixed deleting of checks/comments on unit deletion.
• Added option to disable automatic propagation of translations.
• Added option to subscribe for merge failures.
• Correctly import on projects which needs custom ttkit loader.
• Added sitemaps to allow easier access by crawlers.
• Provide direct links to string in notification emails or feeds.
• Various improvements to admin interface.
• Provide hints for production setup in admin interface.
• Added per language widgets and engage page.
• Improved translation locking handling.
• Show code snippets for widgets in more variants.
• Indicate failing checks or fuzzy strings in progressbars.
• More options for formatting commit message.
• Fixed error handling with machine translation services.
• Improved automatic translation locking behaviour.
• Support for showing changes from previous source string.
• Added support for substring search.
• Various quality checks improvements.
• Support for per project ACL.
• Basic unit tests coverage.

You can find more information about Weblate on it's website, the code is hosted on Github. If you are curious how it looks, you can try it out on demo server. You can login there with demo account using demo password or register your own user. Ready to run appliances will be soon available in SUSE Studio Gallery. Weblate is also being used https://l10n.cihar.com/ as official translating service for phpMyAdmin, Gammu, Weblate itself and others. If you are free software project which would like to use Weblate, I'm happy to help you with set up or even host Weblate for you (this will be decided case by case as my hosting space is limited).

Filed under: English Phpmyadmin Suse Weblate 0 comments Flattr this!

Yesterday, I asked for testers for my prototype for making Debian better at handling pluggable hardware devices, which I set out to create earlier this month. Several valuable testers showed up, and caused me to really want to to open up the development to more people. But before I did this, I want to come up with a sensible name for this project. Today I finally decided on a new name, and I have renamed the project from hw-support-handler to this new name. In the process, I moved the source to git and made it available as a collab-maint repository in Debian. The new name? It is Isenkram. To fetch and build the latest version of the source, use

git clone http://anonscm.debian.org/git/collab-maint/isenkram.git
cd isenkram && git-buildpackage -us -uc

I have not yet adjusted all files to use the new name yet. If you want to hack on the source or improve the package, please go ahead. But please talk to me first on IRC or via email before you do major changes, to make sure we do not step on each others toes. :) If you wonder what 'isenkram' is, it is a Norwegian word for iron stuff, typically meaning tools, nails, screws, etc. Typical hardware stuff, in other words. I've been told it is the Norwegian variant of the German word eisenkram, for those that are familiar with that word. Update 2013-01-26: Added -us -us to build instructions, to avoid confusing people with an error from the signing process. Update 2013-01-27: Switch to HTTP URL for the git clone argument to avoid the need for authentication.

Recently I recieved a MyAudio Tablet Series9 as a gift. From the factory it runs some version of Android, but I already got enough Android devices. Instead I wanted to play a bit with a basic Linux install. This tablet is based on the AllWinner A10 System on a Chip. Some of these instructions might work for other systems based on the same chip set: Step 1: Install the rescue system from http://forum.doozan.com/read.php?6,9396 on a SD-card. You can configure network settings in rescue/interfaces and rescue/wpa_supplicant.conf. Step 2: Boot the rescue system. The MyAudio table will boot from the SD-card if it contains a bootable system, so this is quite easy. The first time you boot the rescue system tries to locate a system.bin file from the tablet. this file contains the hardware configuration and is needed for initializing all the hardware. This means that the screen can t be initialized the first time you boot and will just appear off. Unless the system automatically boots again you need to locate the system.bin yourself from the tablet. It is usually located on /dev/nanda and have names like system.bin, script.bin, or evb.bin. To find the file you can use the log the rescue system places in log/deviceinfo.log on the SD-card during boot. You should now have console access to the tablet and using a USB keyboard you should be able to work in the console. Step 3: Setting up the network Having configured rescue/interfaces and rescue/wpa_supplicant.conf the network ought to work. I am experiencing some problems getting it to connect to my Access Point (using WPA2). Patience works, but you might need to monitor the status with wpa_cli(8) and then run udhcp -i wlan0 when it succeeds. Step 4: Install Debian using the installer at http://forum.doozan.com/read.php?6,8906 This just worked fine Step 5: Getting the touch screen to work. The system.bin file can be decoded with the fexc utility either available on the rescue system (compiled for arm) of from https://github.com/linux-sunxi/sunxi-tools. Finding the ctp_para section we can see that this tablet uses a ft5x touch screen. Adding ft5x_ts to /etc/modules on our installed system will make sure that the correct kernel module gets loaded on boot time. But for some reason the kernel driver and the X11 evdev driver will not talk together. So we need to compile our own kernel patched as described on https://www.miniand.com/forums/forums/development/topics/how-do-i-get-the-lcd-display-and-touch-screen-working-on-an-a10-tablet#post-1225. I have made kernel packages for Debian available at http://hacking.dk/files/linux-image-3.0.57-sun4i+_1.0+nomultitouch_armhf.deb or http://hacking.dk/files/linux-image-3.4.24-sun4i+_1.0+nomultitouch_armhf.deb. Install the kernel package you want and run this as root:

# KERNEL_VERSION=3.4.24-sun4i+
# /usr/bin/mkimage -A arm -O linux -T kernel  -C none -a 0x40008000 -e 0x40008000 -n Linux-$KERNEL_VERSION -d /boot/vmlinuz-$KERNEL_VERSION /boot/uImage
# /usr/bin/mkimage -A arm -O linux -T ramdisk -C gzip -a 0x00000000 -e 0x00000000 -n initramfs-$KERNEL_VERSION -d /boot/initrd.img-$KERNEL_VERSION /boot/uInitrd

After a reboot X11 will respond to the touch screen, but Step 6: Configure the touch screen the pointer does not point where I touch the screen. The transformation between the points are wrong. This is fixed by adding this to your xorg.conf:

Section "InputClass"
    Identifier     "touchscreen"
    MatchProduct   "ft5x_ts"
    Option    "TransformationMatrix" "0 1 0 1 0 0 0 0 1"
    Option    "Calibration" "0 768 0 1024"
EndSection

or more dynamically by running:

$ xinput set-prop ft5x_ts "Coordinate Transformation Matrix" 0 1 0 1 0 0 0 0 1
$ xinput set-prop ft5x_ts "Evdev Axis Calibration" 0 768 0 1024

For more information about the Transformation Matrix, see the X.Org Wiki Step 7: Install a on-screen keyboard. I have not found the perfect keyboard application yet. Currently I am using matchbox-keyboard