Category Archives: exo

Xfce 4.8 Schedule Changes

community, DeviceKit-disks, exo, gio, HAL, identica, libxfce4menu, libxfce4ui, releases, studies, thunar, thunar-volman, udev, university, volume management, work, Xfce, xfce4-settings, xfce46, xfce48

As the Xfce release manager, I’d prefer to be the bringer of good news. Unfortunately, we have to make some adjustments with regards to the Xfce 4.8 release schedule.

You may well remember last year’s chaos with the 4.6 release date. We’re trying our best not to repeat that and if it should happen again, we’ll at least keep you posted about the issues as good as we can.

So, what’s the deal with 4.8?

One thing that hasn’t changed much is that our development team is very small. A hobby project of this size requires a certain amount of time to be invested by each individual developer. Time not everyone has as much has he would like to dedicate to Xfce.

Today, Brian announced his absence for the coming months due to his new job, leaving 2-3 of our core components (xfdesktop, xfconf and xfce4-session) more or less unmaintained (aside from bugfixes). The good news is that Jérôme (who has recently started to improve xfce4-settings and port xfce4-session to libxfce4ui) and Daniel (the maintainer of the thunar-shares-plugin) have offered their help with xfdesktop and xfce4-session.

Brian is not the only one having little time at hand though. I’m preparing myself for my final university exams, so ideally I’d be sticking my nose into lecture notes all day long. I still have the time to write mails like this but there hasn’t been much activity around thunar and related projects lately.

Again, I’m really happy to see people volunteering to help because that’s what we need right now. There’s a lot left to do before we can release 4.8. Let me get to that now.

As some of might have heard, thunar was ported to GIO this summer. Through GVfs, GIO brings new features such as SMB, SFTP, FTP browsing which some people use one a daily basis already. Now, GVfs has turned out to be problematic for us for various reasons. At first it shipped a HAL-based volume monitor with a hard-coded dependency on gnome-mount. Today it ships a volume monitor based on gnome-disk-utility (uses DeviceKit-disks itself) which proves to be inconsistent and somewhat incompatible to the HAL mounting code in exo.

The result: thunar-volman (not part of the core but important for thunar nonetheless) and xfdesktop will have to be ported to udev (the mounting being done with GIO, ideally). I’ve started working on this but this is far from being finished.

Question to the other developers: Didn’t xfce4-session use HAL for logging out and stuff? We might have to look into replacing those portions of code with something based on ConsoleKit, I guess?

HAL/udev is not the only issue however. With Xfce 4.8 we’ll be replacing libxfcegui4 with a new library called libxfce4ui. Not all core applications (again, xfdesktop being one of them, I think) have been ported to it yet. In most cases, this is no big deal and probably could be resolved within a few days though.

Then we have garcon, the much improved menu library that is supposed to replace libxfce4menu. At the time of writing the only feature it is lacking that is crucial for 4.8 is file system monitoring. We’ll probably implement basic monitoring like we had in libxfce4menu. Work on this hasn’t started yet.

Also, xfdesktop needs to be ported not only from ThunarVFS/HAL to GIO/udev but also from libxfce4menu to garcon.

So, as you can see there is quite a lot of work ahead of us. Taking into account the little free time some of us have these days, we’ve decided to postpone the 4.8 release until June 12th instead of April 12th. The entire release phase in our schedule has been moved by two months in time, as you can see on the official schedule wiki page:

 http://wiki.xfce.org/releng/4.8/schedule

To be honest, I wouldn’t consider this new date fixed either. It all depends on how much we can do until the feature freeze on April 1st. I’m optimistic that meeting the deadlines is possible though.

For all of you who can’t wait until June, try out our development releases which are announced on http://identi.ca/xfce. I have at least something good to share: For a few weeks now I’ve been running Fedora 12 with a mixture of Xfce 4.6 packages and development package from the upcoming 4.8 series and the new components have proven to be very stable already.

I’m especially happy about the new panel which works almost flawlessly (except for a few dual head issues) and not only supports real transparency and more comfortable launcher creation based on garcon, but is also compatible to panel plugins written for Xfce 4.6. (Good work, Nick!)

So, I guess this is it. A mixture of good and bad. I hope nobody is too disappointed. As always, we’re doing the best we can.

Cheers!

Thunar-volman and the deprecation of HAL in Xfce

community, DeviceKit-disks, exo, gio, HAL, survey, thunar, thunar-volman, udev, udisks, volume management, Xfce, xfce48

Last week I started looking at thunar-volman (a program that performs certain actions when new devices are plugged in) with the goal to make it compatible with the latest release of thunar which uses GIO instead of ThunarVFS for almost everything that takes place under the hood.

Until now, volume management (monitoring and mounting) in Xfce was done through HAL, the hardware abstraction layer that is currently being deprecated and dropped by major distributions. The functionality previously provided by HAL has been moved into udev, udisks (formerly known as DeviceKit-disks) and upower (formerly known as DeviceKit-power).

Volume management is transparently supported by GIO, meaning that applications don’t have to worry about the backend implementation. It should, in theory, not matter whether HAL is used or udev/udisks. Unsurprisingly, in reality, things are not that trivial, mainly for two reasons:

  1. Due to its focus on file management, GIO only supports monitoring and detecting storage devices (DVD drives, USB sticks etc.). There is no way to be notified when e.g. a digital camera or a portable media player is plugged in. This is critical for the functionality of thunar-volman which until now supported everything from cameras, media players, blank CDs/DVDs, audio CDs, PDAs and printers to input devices like keyboards, mice and tablets.
  2. Mounting volumes with udisks seems to be somewhat incompatible with HAL. I tried to mount volumes with thunar-volman and exo-mount (both implemented on top of HAL) and was for the root password upon unmounting in Thunar (using GIO and gnome-disk-utility/DeviceKit-disks). It seems like volumes mounted with HAL are assumed to be mounted by a different than the current user and thus, require root privileges to be unmounted.

HAL being deprecated and somewhat incompatible with udisks, what are the consequences for Xfce, and for thunar and thunar-volman in particular?

Let us, for a moment, assume Xfce 4.8 and thunar 1.0 were released as they are today, with thunar using GIO (and udisks instead of HAL in all major Linux distributions) and the rest (like thunar-volman and exo-mount) depending on HAL. As mentioned before, exo-mount and thunar wouldn’t work together in multi-user setups. Thunar would no longer detect cameras, PDAs, audio CDs, blank disks, mice, keyboards, tablets, media players and thunar-volman would end up being completely useless, as it is not detecting devices by itself. I think it is safe to say that this is not what we want.

In the following, I will focus on how to deal with thunar-volman. The rest of Xfce faces a similar roadmap, however. With regards to thunar-volman, there are (at least) three sane options:

  1. Drop thunar-volman and only support auto-mounting storage devices from now on, directly implemented in thunar. What is very obvious about this solution is that a lot of possibly useful functionality is lost.
  2. Port thunar-volman to (g)udev/udisks/GIO and make it a standalone daemon so that thunar no longer has to spawn it when new devices are plugged in. The advantage of this approach is that thunar only needs to depend on GIO and doesn’t have to implement the device detection part.
  3. Port thunar-volman to (g)udev/udisks/GIO as described above and make thunar depend on (g)udev for device detection. Spawn thunar-volman when devices are added/removed. The advantage over the previous approach is that thunar-volman doesn’t have to run permanently as a daemon. The additional thunar dependency on (g)udev could be seen as a disadvantage but on the other hand, it basically replaces another (HAL).

Now, everyone knows that programmers are lazy people. So, in the hope of being able to save some work, I started a survey on the usage of thunar-volman. The idea was to find out which of its features are used most and whether there are some that nobody really cares about. Here are the results:

=======================================================================================
                                                        Feature   #Users   Percentage 
---------------------------------------------------------------------------------------
                        Mount removable drives when hot-plugged       86        92.5%
                            Mount removable media when inserted       83        89.2%
                           Browse removable media when inserted       69        74.2%
             Cameras: Import digital photographs when connected       31        33.3%
                          Play video CDs and DVDs when inserted       31        33.3%
                                   Play audio CDs when inserted       30        32.3%
                 Burn a CD or DVD when a blank disc is inserted       21        22.6%
        Portable Media Players: Play music files when connected       11        11.8%
                      Auto-run programs on new drives and media        7         7.5%
        Automatically run a program when a printer is connected        7         7.5%
                        Auto-open files on new drives and media        6         6.5%
                               Sync Palm devices when connected        5         5.4%
  Automatically run a program when an USB keyboard is connected        3         3.2%
     Automatically run a program when an USB mouse is connected        3         3.2%
         Automatically run a program when a tabled is connected        2         2.2%
                          Sync Pocket PC devices when connected        2         2.2%
=======================================================================================
                Thunar Volume Manager Usage Survey with 93 participants

According to the results of this survey, auto-mounting and browsing of removable drives and media have highest priority among the 93 participating thunar-volman users. This more or less covers the functionality we could cover with GIO alone (plus automatically running a program when new drives and media are inserted). However, a third of the users also use thunar-volman for importing photographs from digital cameras and for playing video and audio CDs as well as DVDs automatically. Almost a 25 percent of all users use thunar-volman to start their favorite burning software when a blank CD or DVD is inserted. Slightly more than 10 percent want thunar-volman to start playing music on portable media players when they are plugged in. Printers and Palms are also somewhat relevant.

This survey confirms my expectations that handling storage devices alone is not enough even though they clearly are the most important use case for thunar-volman. Our users seem to like the flexibility of thunar-volman and make use of it. This disqualifies option 1 and leaves us with options 2 and 3. I’m inclined to avoid another daemon and go for number 3.

In preparation for porting thunar and thunar-volman to udev/udisks/GIO, I’ve created a wiki page to collect information about how we can reliably distinguish the different device types based on udev properties: http://wiki.xfce.org/dev/thunar-volman-udev. If you have blue-ray disks, video CDs, a digital camera, a Pocket PC, a Palm, a USB printer or a graphics tablet, you could make me very happy if you inserted them or plugged them in and sent me the output of udevadm info --export-db to my Xfce email address together with a short hint what devices you’ve plugged in. Alternatively, you can paste/upload the output somewhere on the internet and comment on this blog post, and thereby help making future versions of Xfce better.

Cheers!

Xfce 4.8 Release Cycle Information

community, exo, gio, libxfce4ui, releases, thunar, Xfce, xfce4-appfinder, xfce4-settings, xfce48, xfdesktop
At the end of August, we've entered the development phase for the Xfce 4.8 release cycle. Today, we're hitting dependency freeze and I think this is a good time to inform you about how the cycle will look like and what we're planning to achieve for 4.8.

The final 4.8 release is scheduled for April 12th, 2010, which is in about 8 months. We're trying to stick to a well-defined release policy for the first time. This includes frequent development releases of individual components and, most importantly, a time-based release cycle.

I'm confident that we can meet the schedule you can see below and would like to encourage everyone to participate in the development and continued improvement of Xfce 4.8, be it as a developer, a translator or a generally active member of the Xfce community.

Below you find detailed information about the 4.8 schedule, the release team, dependencies and planned features. This information is also available on the wiki.

Schedule

2009-08-16 - 2009-08-30: Planning phase
2009-08-31 - 2009-09-13: Extended planning phase
             2009-09-13: Dependency freeze

2009-08-31 - 2010-01-31: Development phase
2010-02-01 - 2010-04-12: Release phase

             2010-02-01: Xfce 4.8pre1 release / Feature freeze
             2010-03-01: Xfce 4.8pre2 release / String freeze
             2010-03-29: Xfce 4.8pre3 release / Code freeze

             2010-04-12: Xfce 4.8 final release

Release Team

   Release Manager: Jannis Pohlmann
       QA Official: Stephan Arts
Release Assistants: Jérôme Guelfucci
                    Ali Abdallah
                    Yves-Alexis Perez
                    Robby Workman
                    Vincent Tunru

You can read up on the roles of these people on this page if you feel like you need to contact one of them because there's something going wrong with the development or release process.

Dependencies

Xfce 4.8 will depend on the following libraries and applications:

  • cairo >= 1.0.0
  • dbus-1 >= 1.0.0
  • dbus-glib-1 >= 0.73
  • gdk-pixbuf-2.0 >= 2.14.0
  • gio-2.0 >= 2.18.0
  • glib-2.0 >= 2.18.0
  • gmodule-2.0 >= 2.18.0
  • gobject-2.0 >= 2.18.0
  • gthread-2.0 >= 2.18.0
  • gtk+-2.0 >= 2.14.0
  • libpng12 >= 1.2.0
  • libwnck-1.0 >= 2.22
  • x11 >= 1.1.0

The following dependencies are still left open:

  • garcon-1 (no release yet, but used in different places)
  • tumbler (no release yet, but used in different places)
  • sphinx (for documentation)

Planned Features

In the following, we give you an overview of the features we are planning to implement for 4.8. Please note that due to the voluntary nature of the Xfce development, none of features are guaranteed to make it into the final release. This feature list may also not be complete as we might be able to implement even more during the cycle. This list is meant to give you an insight in what we're up to and what you might be able to expect in 8 months.

You can find a (hopefully) always up to date list on the wiki page. Each of the pages linked there contains more detailed information about the features, their implementation status and sometimes also who has taken the responsibility to work on them.

We welcome people to help in achieving these goals. All of our repositories are now managed using git (on http://git.xfce.org/) so it's easy to clone them and contribute code to Xfce.

exo

  • Remove deprecated APIs and rename library to exo-1
  • Add GIO module for URI handling to support gtk_show_uri()

libxfce4ui

  • Port all Xfce core components to libxfce4ui instead of libxfcegui4
  • Object-oriented session client
  • GtkBuilder support for e.g. XfceTitledDialog

thunar

  • Finish the migration to GIO/GVfs. Among other features, this will give us network browsing (windows shares, SSH, FTP etc.).
  • Implement our own volume monitoring backend for GIO (based on HAL or DeviceKit-disks)
  • Update thunar-volman to work with this volume monitoring backend and port it to xfconf
  • Integration of remote locations in the side pane
  • Improve integration of tumbler for thumbnailing
  • Port all ThunarVFS thumbnailers to tumbler, write backwards-compatible tumbler plugin for thunar-thumbnailers
  • Use a single progress dialog, grouping all file operations
  • Extend the D-Bus interface so that e.g. xfdesktop can re-use the file properties dialog
  • Startup notification support in the custom actions plugin

xfce4-appfinder

  • Drop libxfce4menu and migrate to garcon
  • Improve keyboard navigation
  • Use startup notification when spawning applications
  • Perhaps implement an extension API, so that xfce4-appfinder can act as a replacement for xfrun4 in the future.

xfce4-panel

  • Finish the completely rewritten panel. This adds a lot of neat features and revamped dialogs. Amongst other things:
  • Introduce an xfconf API for plugins
  • Add an improved launcher plugin based on GIO, garcon and exo-desktop-item-edit
  • Improved transparency support
  • Better panel placement and multi-head support

xfce4-settings

  • Netbook-friendly dialogs
  • Improve keyboard shortcuts (seem to cause a lot of problems)
  • Improve display and pointer settings dialogs
  • Add a clipboard manager daemon
  • Finish/fix the settings editor

xfdesktop

  • Use GIO for the icon view
  • Use garcon for the menu instead of libxfce4menu
  • Improve icon view drawing routines
  • Proper keyboard handling for the icon view
  • Free icon positioning
  • Allow right-click menus to be arranged differently

I think that's it. I hope you enjoy Xfce and are looking forward to the 4.8 release together with us!