Search Results: "guillem"

6 April 2014

Stefano Zacchiroli: historical overview of debian source code

moar, and moar, and moar debsources stats A while ago I've announced the availability of several stats about Debian source code on http://sources.debian.net. Since then the statistical basis of those stats has increased a lot, and now includes all Debian historical releases, from hamm (July 1998) onward. This allows to appreciate macro-level evolution trends in Free Software, over a period of more than 15 years, through the eyes of a distro that sits at the nice intersection of the eldest, largest, and most reputed distros. To get there I've added support for sticky suites to the plumbing layer of debsources, and then injected historical releases from http://archive.debian.org. The injection process took about a week (without any sort of parallelism, pretty slow disks, and computing sha256 checksums, ctags, and sloccount on all source files) and has been an "interesting" experience. When you go back decades in technology time, bit rot is just around the corner, and I've found my share while injecting archive.d.o into sources.d.n. In both cases the respective maintainers (Guillem and Ganneff, kudos) have been positive about and helpful in improving the situation, despite the low impact of the bugs I've found on the average user. That's quite important for the long-term preservation of digital information in general, and for the perennity of access to Free Software in the specific case of Debian. While we are it, I'm now maintaining a list of bugs affecting sources.d.n but belonging to other packages, in case you fancy helping out but are not a Python hacker. Interestingly enough, quite a bit of those bugs are related to the fact that tools debsources uses (e.g. ctags, sloccount) are also starting to show their age. You might wander why buzz, rex, and bo are still missing from sources.d.n. That's in fact for similar reasons. Before hamm Debian didn't have complete archive coverage in terms of Sources indexes and .dsc files. Given that debsources rely on both to extract source packages, it first needs to grow an additional abstraction layer that can cope with their absence. It's SMOP, and planned. And now let's have fun with ctags bombs. Yours truly,
Stefano Indiana Zacchiroli
(credits: KiBi, #debian-ftp)

20 January 2014

Enrico Zini: terminal-emulators

Quest for a terminal emulator The requirements I need a terminal emulator. This is a checklist of the features that I need: My experience is that getting all of this to work is not being as easy as it seems, so I'm creating this page to track progress. gnome-terminal I've been happily using this for years, and it did everything I needed, until some months ago it started to open new tabs in the terminal's working directory instead of the last tab's working directory. This is a big point of frustration for me. It also started opening https urls with Firefox, although the preferred browser was Chromium. There seemed to be no way to control it: I looked for firefox or iceweasel in all gconf and dconf settings and found nothing. The browser issue was fixed by accident when I used Xfce4's settings application to change the browser from Chromium to Firefox and then back to Chromium. update, thanks to Mathieu Parent, Josh Triplett, Peter De Wachter, Julien Cristau, and Charles Plessy: It is also possible to restore the "new tab opened inside the same directory of the last tab I was in" behaviour, by enabling "run command as a login shell" so that /etc/profile.d/vte.sh is run (thanks Mathieu Parent for the link). That in turn spawned extra cleanup work in my .bashrc/.bash_profile/.profile setup, which has been randomly evolving since even before my first Debian "buzz" system. I found that it was setting PROMPT_COMMAND to something else to set the terminal title, conflicting with what vte.sh wants to do. With regards to loading /etc/profile.d/vte.sh by default, Peter De Watcher sent pointers to relevant bugs: here, here, and here. An alternative strategy is to work using the prompt rather than PROMPT_COMMAND; an example is in Josh Triplett's .bashrc from git://joshtriplett.org/git/home. Josh Triplett also said:
To fix the browser launched for URLs, you either need to use a desktop environment following GNOME's mechanism for setting the default browser, or edit ~/.local/share/applications/mimeapps.list and make sure x-scheme-handler/http, x-scheme-handler/https, and x-scheme-handler/ftp are set to your preferred browser's desktop file basename under [Added Associations].
All my issues with gnome-terminal are now gone and I'm only too happy to go back to it. rxvt-unicode-256color urxvt took some work. This is where I got with configuration:
URxvt.font: xft:Monospace-10:antialias=true
URxvt.foreground: #aaaaaa
URxvt.background: black
URxvt.scrollBar_right: true
URxvt.cursorBlink: true
URxvt.perl-ext-common: default,matcher,tabbedex
URxvt.url-launcher: /usr/bin/x-www-browser
URxvt.matcher.button: 1
URxvt.perl-lib: /home/enrico/.urxvt/perl
URxvt.color0: black
URxvt.color1: #aa0000
URxvt.color2: #00aa00umask
URxvt.color3: #aa5500
URxvt.color4: #0000aa
URxvt.color5: #aa00aa
URxvt.color6: #00aaaa
URxvt.color7: #aaaaaa
URxvt.color8: #555555
URxvt.color9: #ff5555
URxvt.color10: #55ff55
URxvt.color11: #ffff55
URxvt.color12: #5555ff
URxvt.color13: #ff55ff
URxvt.color14: #55ffff
URxvt.color15: #ffffff
I got all of the tab behaviour that I need by "customizing" the tab script (yuck github :( ). Missing sakura Configuration is in .config/sakura/sakura.conf and these bits help:
colorset1_fore=rgb(170,170,170)
colorset1_back=rgb(0,0,0)
colorset1_opacity=99
colorset2_fore=rgb(0,0,0)
colorset2_back=rgb(254,254,254)
colorset2_opacity=99
font=Monospace 10
show_always_first_tab=No
scrollbar=false
fullscreen_key=F11
palette=linux
Missing lxterminal Configuration is in .config/lxterminal/lxterminal.conf and this is relevant to me:
[general]
fontname=DejaVu Sans Mono 10
fgcolor=#aaaaaaaaaaaa
disallowbold=false
cursorblinks=true
tabpos=top
hidescrollbar=false
hidemenubar=true
hideclosebutton=true
disablef10=true
disablealt=true
Also, to open a url directly you control+click it. Missing terminator Configuration is in .config/terminator/config and this is relevant to me:
[global_config]
  use_custom_url_handler = True
  custom_url_handler = x-www-browser
  inactive_color_offset = 1.0
[keybindings]
  close_term = None
  close_window = None
  copy = None
  cycle_next = None
  cycle_prev = None
  go_down = None
  go_next = None
  go_prev = None
  go_up = None
  group_all = None
  group_tab = None
  hide_window = None
  move_tab_left = None
  move_tab_right = None
  new_tab = None
  new_terminator = None
  new_window = None
  next_tab = None
  paste = None
  prev_tab = None
  reset_clear = None
  reset = None
  resize_down = None
  resize_left = None
  resize_right = None
  resize_up = None
  rotate_ccw = None
  rotate_cw = None
  scaled_zoom = None
  search = None
  split_horiz = None
  split_vert = None
  switch_to_tab_1 = <Alt>F1
  switch_to_tab_2 = <Alt>F2
  switch_to_tab_3 = <Alt>F3
  switch_to_tab_4 = <Alt>F4
  switch_to_tab_5 = <Alt>F5
  switch_to_tab_6 = <Alt>F6
  switch_to_tab_7 = <Alt>F7
  switch_to_tab_8 = <Alt>F8
  switch_to_tab_9 = <Alt>F9
  switch_to_tab_10 = <Alt>F10
  toggle_scrollbar = None
  toggle_zoom = None
  ungroup_all = None
  ungroup_tab = None
[profiles]
  <span class="createlink">default</span>
    palette = "#000000:#aa0000:#00aa00:#aa5500:#0000aa:#aa00aa:#00aaaa:#aaaaaa:#555555:#ff5555:#55ff55:#ffff55:#5555ff:#ff55ff:#55ffff:#ffffff"
    copy_on_selection = True
    icon_bell = False
    background_image = None
    show_titlebar = False
Missing update: Richard Hartmann pointed out that terminator's upstream maintainer now changed after the old one didn't have time any more, and it should have a release with a ton of improvements anytime soon. xfce4-terminal Configuration is in .config/xfce4/terminal, and this is relevant to me: terminalrc:
[Configuration]
FontName=Monospace 10
MiscAlwaysShowTabs=FALSE
MiscBell=FALSE
MiscBordersDefault=TRUE
MiscCursorBlinks=FALSE
MiscCursorShape=TERMINAL_CURSOR_SHAPE_BLOCK
MiscDefaultGeometry=80x24
MiscInheritGeometry=FALSE
MiscMenubarDefault=FALSE
MiscMouseAutohide=FALSE
MiscToolbarDefault=FALSE
MiscConfirmClose=TRUE
MiscCycleTabs=TRUE
MiscTabCloseButtons=TRUE
MiscTabCloseMiddleClick=TRUE
MiscTabPosition=GTK_POS_TOP
MiscHighlightUrls=TRUE
ShortcutsNoMenukey=TRUE
ShortcutsNoMnemonics=TRUE
ColorForeground=#aaaaaaaaaaaa
accels.scm:
(gtk_accel_path "<Actions>/terminal-window/goto-tab-1" "<Alt>F1")
(gtk_accel_path "<Actions>/terminal-window/goto-tab-2" "<Alt>F2")
(gtk_accel_path "<Actions>/terminal-window/goto-tab-3" "<Alt>F3")
(gtk_accel_path "<Actions>/terminal-window/goto-tab-4" "<Alt>F4")
(gtk_accel_path "<Actions>/terminal-window/goto-tab-5" "<Alt>F5")
(gtk_accel_path "<Actions>/terminal-window/goto-tab-6" "<Alt>F6")
(gtk_accel_path "<Actions>/terminal-window/goto-tab-7" "<Alt>F7")
(gtk_accel_path "<Actions>/terminal-window/goto-tab-8" "<Alt>F8")
(gtk_accel_path "<Actions>/terminal-window/goto-tab-9" "<Alt>F9")
(gtk_accel_path "<Actions>/terminal-window/goto-tab-10" "<Alt>F10")
(gtk_accel_path "<Actions>/terminal-window/goto-tab-11" "<Alt>F11")
(gtk_accel_path "<Actions>/terminal-window/goto-tab-12" "<Alt>F12")
update: Yves-Alexis Perez points out that to disable the F1 for help in the terminal, you need to remove the accelerator. I tried this and this and didn't have success, but I confess I did not dig too much into it. Although xfce4-terminal -e does not work as I expect, xfce4-terminal registers a wrapper for x-terminal-emulator that does the right thing with respect to -e (also thanks Yves-Alexis Perez). Missing roxterm Configuration is in .config/roxterm.sourceforge.net/ split in several files corresponding to profiles. This is a reasonable starting point for me: Profiles/Default:
[roxterm profile]
colour_scheme=Default
disable_menu_access=1
disable_menu_shortcuts=1
disable_tab_menu_shortcuts=0
tab_close_btn=0
hide_menubar=1
always_show_tabs=0
Colours/Default:
[roxterm colour scheme]
0=#000000000000
1=#aaaa00000000
2=#0000aaaa0000
3=#aaaa55550000
4=#00000000aaaa
5=#aaaa0000aaaa
6=#0000aaaaaaaa
7=#aaaaaaaaaaaa
8=#555555555555
9=#ffff55555555
10=#5555ffff5555
11=#ffffffff5555
12=#55555555ffff
13=#ffff5555ffff
14=#5555ffffffff
15=#ffffffffffff
palette_size=16
foreground=#aaaaaaaaaaaa
background=#000000000000
cursor=#cccccccccccc
bold=
dim=
Shortcuts/Default:
[roxterm shortcuts scheme]
File/New Window=
File/New Tab=
File/Close Window=
File/Close Tab=
Tabs/Previous Tab=
Tabs/Next Tab=
Edit/Copy=
Edit/Paste=
View/Zoom In=<Control>plus
View/Zoom Out=<Control>minus
View/Normal Size=<Control>0
View/Full Screen=F11
View/Scroll Up One Line=
View/Scroll Down One Line=
Help/Help=
Edit/Copy & Paste=
Search/Find...=
Search/Find Next=
Search/Find Previous=
File/New Window With Profile/Default=
File/New Tab With Profile/Default=
Tabs/Select_Tab_0=<Alt>F1
Tabs/Select_Tab_1=<Alt>F2
Tabs/Select_Tab_2=<Alt>F3
Tabs/Select_Tab_3=<Alt>F4
Tabs/Select_Tab_4=<Alt>F5
Tabs/Select_Tab_5=<Alt>F6
Tabs/Select_Tab_6=<Alt>F7
Tabs/Select_Tab_7=<Alt>F8
Tabs/Select_Tab_8=<Alt>F9
Tabs/Select_Tab_9=<Alt>F9
Tabs/Select_Tab_10=<Alt>F10
Tabs/Select_Tab_11=<Alt>F11
Tabs/Select_Tab_12=<Alt>F12
Global:
[roxterm options]
edit_shortcuts=0
prefer_dark_theme=1
colour_scheme=Default
warn_close=1
Missing Nothing of my initial requirements seems to be missing, really, so I'm sticking to it for a while to see what happens. The first itch to scratch is that when the menubar is hidden, the popup menu becomes the entire menubar contents, which does not fit the general use case to have a contextual menu with the most common shortcuts. I'll just declare it useless and get myself used to some new hotkey for starting a new terminal. update: after fixing my issues with gnome-terminal I've switched back to gnome-terminal: its interface feels less clunky as I'm already used to it. Other references Guillem Jover made a similar analysis in 2009, it can be found here. Thomas Koch mentioned that termit should be able to do all I need, and is scriptable in Lua. I like the sound of that, and it's definitely one I should look next time I find myself shopping for terminal emulators.

5 January 2014

Russ Allbery: More on displaying files with head

That was fun! Since my previous entry on using head to display the contents of several files in a form that's easy to cut and paste, multiple people have sent elaborations or related tricks. It seemed like it would be a good idea to post a roundup, since I learned a bunch. Multiple people (I think Josh Triplett was the first) pointed out that one can avoid having to pick a sufficiently large value of -n by instead using:
    head -n -0 *.install
With GNU head at least, a negative number says to print out all lines of the file except that many at the end, so -0 displays the whole file, regardless of size. Unfortunately, while this works anywhere that I am likely to run it, it's not specified by POSIX, while the original is. Another variation, pointed out by Buck Huppmann, is:
    tail -n +0 *.install
The +0 syntax is required by POSIX, unlike the -0 syntax for head... but unfortunately POSIX doesn't require that tail supports multiple files and the headers, although it does for head. Buck also pointed out that including the -v flag will always force the header even if there's only one file, which is useful. (Although be warned that -v isn't a POSIX-recognized flag.) Markus Raab also pointed out the xsel utility, which I'd heard of but hadn't ever used. If the goal is to cut and paste the output, using:
    head -v -n -0 *.install   xsel -i
avoids the cut part by dumping the result directly into the X selection. Buck pointed out xclip, which does the same thing. Both can be used with the -o flag inside an editor to paste as well if you don't want to reach for a mouse. In vi :r !xclip -o, and in Emacs, C-u M-! xclip -o. Finally, Guillem Jover metioned that:
    grep . *.install
does sort of the same thing with a different output format that may be more useful depending on what you're doing. (I find it less human-readable but more machine-parsable.)

28 July 2013

Hideki Yamane: now dpkg-deb uses xz for compression by default

from dpkg 1.17.0 's changelog

 dpkg (1.17.0) unstable; urgency=low
.
[ Guillem Jover ]
(snip)
* Switch dpkg-deb default compressor from gzip to xz. Build dpkg.deb using
gzip to make debootstrap life easier on non-Debian based systems.
Hallelujah, thanks! It'll reduce archive size and cut traffic, download time, too :-)

Then, I hope that dpkg would support "package delta" feature like yum's presto.

16 May 2013

Michael Vogt: git fast-import apt

Due to popular demand I moved debian apt and python-apt from bzr to git today. Moving was pretty painless:
$ git init
$ bzr fast-export --export-marks=marks.bzr -b debian/sid /path/to/debian-sid   git fast-import --export-marks=marks.git
And then a fast-import for the debian-wheezy and debian-experimental branches too. Then a
$ git gc --aggressive
(thanks to Guillem Jover for pointing this out) and that was it. The branches are available at:

20 February 2013

Vincent Bernat: lldpd 0.7.1

A few weeks ago, a new version of lldpd, a 802.1AB (aka LLDP) implementation for various Unices, has been released. LLDP is an industry standard protocol designed to supplant proprietary Link-Layer protocols such as EDP or CDP. The goal of LLDP is to provide an inter-vendor compatible mechanism to deliver Link-Layer notifications to adjacent network devices. In short, LLDP allows you to know exactly on which port is a server (and reciprocally). To illustrate its use, I have made a xkcd-like strip: xkcd-like strip for the use of LLDP If you would like more information about lldpd, please have a look at its new dedicated website. This blog post is an insight of various technical changes that have affected lldpd since its latest major release one year ago. Lots of C stuff ahead!

Version & changelog UPDATED: Guillem Jover told me how he met the same goals for libbsd :
  1. Save the version from git into .dist-version and use this file if it exists. This allows one to rebuild ./configure from the published tarball without losing the version. This also handles Thorsten Glaser s critic.
  2. Include CHANGELOG in DISTCLEANFILES variable.
Since this is a better solution, I have adopted the appropriate line of codes from libbsd. The two following sections are partly technically outdated.

Automated version In configure.ac, I was previously using a static version number that I had to increase when releasing:
AC_INIT([lldpd], [0.5.7], [bernat@luffy.cx])
Since the information is present in the git tree, this seems a bit redundant (and easy to forget). Taking the version from the git tree is easy:
AC_INIT([lldpd],
        [m4_esyscmd_s([git describe --tags --always --match [0-9]* 2> /dev/null   date +%F])],
        [bernat@luffy.cx])
If the head of the git tree is tagged, you get the exact tag (0.7.1 for example). If it is not, you get the nearest one, the number of commits since it and part of the current hash (0.7.1-29-g2909519 for example). The drawback of this approach is that if you rebuild configure from the released tarball, you don t have the git tree and the version will be a date. Just don t do that.

Automated changelog Generating the changelog from git is a common practice. I had some difficulties to make it right. Here is my attempt (I am using automake):
dist_doc_DATA = README.md NEWS ChangeLog
.PHONY: $(distdir)/ChangeLog
dist-hook: $(distdir)/ChangeLog
$(distdir)/ChangeLog:
        $(AM_V_GEN)if test -d $(top_srcdir)/.git; then \
          prev=$$(git describe --tags --always --match [0-9]* 2> /dev/null) ; \
          for tag in $$(git tag   grep -E '^[0-9]+(\.[0-9]+) 1, $$'   sort -rn); do \
            if [ x"$$prev" = x ]; then prev=$$tag ; fi ; \
            if [ x"$$prev" = x"$$tag" ]; then continue; fi ; \
            echo "$$prev [$$(git log $$prev -1 --pretty=format:'%ai')]:" ; \
            echo "" ; \
            git log --pretty=' - [%h] %s (%an)' $$tag..$$prev ; \
            echo "" ; \
            prev=$$tag ; \
          done > $@ ; \
        else \
          touch $@ ; \
        fi
ChangeLog:
        touch $@
Changelog entries are grouped by version. Since it is a bit verbose, I still maintain a NEWS file with important changes.

Core

C99 I have recently read 21st Century C which has some good bits and also handles the ecosystem around C. I have definitively adopted designated initializers in my coding style. Being a GCC extension since a long time, this is not a major compatibility problem. Without designated initializers:
struct netlink_req req;
struct iovec iov;
struct sockaddr_nl peer;
struct msghdr rtnl_msg;
memset(&req, 0, sizeof(req));
memset(&iov, 0, sizeof(iov));
memset(&peer, 0, sizeof(peer));
memset(&rtnl_msg, 0, sizeof(rtnl_msg));
req.hdr.nlmsg_len = NLMSG_LENGTH(sizeof(struct rtgenmsg));
req.hdr.nlmsg_type = RTM_GETLINK;
req.hdr.nlmsg_flags = NLM_F_REQUEST   NLM_F_DUMP;
req.hdr.nlmsg_seq = 1;
req.hdr.nlmsg_pid = getpid();
req.gen.rtgen_family = AF_PACKET;
iov.iov_base = &req;
iov.iov_len = req.hdr.nlmsg_len;
peer.nl_family = AF_NETLINK;
rtnl_msg.msg_iov = &iov;
rtnl_msg.msg_iovlen = 1;
rtnl_msg.msg_name = &peer;
rtnl_msg.msg_namelen = sizeof(struct sockaddr_nl);
With designated initializers:
struct netlink_req req =  
    .hdr =  
        .nlmsg_len = NLMSG_LENGTH(sizeof(struct rtgenmsg)),
        .nlmsg_type = RTM_GETLINK,
        .nlmsg_flags = NLM_F_REQUEST   NLM_F_DUMP,
        .nlmsg_seq = 1,
        .nlmsg_pid = getpid()  ,
    .gen =   .rtgen_family = AF_PACKET  
 ;
struct iovec iov =  
    .iov_base = &req,
    .iov_len = req.hdr.nlmsg_len
 ;
struct sockaddr_nl peer =   .nl_family = AF_NETLINK  ;
struct msghdr rtnl_msg =  
    .msg_iov = &iov,
    .msg_iovlen = 1,
    .msg_name = &peer,
    .msg_namelen = sizeof(struct sockaddr_nl)
 ;

Logging Logging in lldpd was not extensive. Usually, when receiving a bug report, I asked the reporter to add some additional printf() calls to determine where the problem was. This was clearly suboptimal. Therefore, I have added many log_debug() calls with the ability to filter out some of them. For example, to debug interface discovery, one can run lldpd with lldpd -ddd -D interface. Moreover, I have added colors when logging to a terminal. This may seem pointless but it is now far easier to spot warning messages from debug ones. logging output of lldpd

libevent In lldpd 0.5.7, I was using my own select()-based event loop. It worked but I didn t want to grow a full-featured event loop inside lldpd. Therefore, I switched to libevent. The minimal required version of libevent is 2.0.5. A convenient way to check the changes in API is to use Upstream Tracker, a website tracking API and ABI changes for various libraries. This version of libevent is not available in many stable distributions. For example, Debian Squeeze or Ubuntu Lucid only have 1.4.13. I am also trying to keep compatibility with very old distributions, like RHEL 2, which does not have a packaged libevent at all. For some users, it may be a burden to compile additional libraries. Therefore, I have included libevent source code in lldpd source tree (as a git submodule) and I am only using it if no suitable system libevent is available. Have a look at m4/libevent.m4 and src/daemon/Makefile.am to see how this is done.

Client

Serialization lldpctl is a client querying lldpd to display discovered neighbors. The communication is done through an Unix socket. Each structure to be serialized over this socket should be described with a string. For example:
#define STRUCT_LLDPD_DOT3_MACPHY "(bbww)"
struct lldpd_dot3_macphy  
        u_int8_t                 autoneg_support;
        u_int8_t                 autoneg_enabled;
        u_int16_t                autoneg_advertised;
        u_int16_t                mau_type;
 ;
I did not want to use stuff like Protocol Buffers because I didn t want to copy the existing structures to other structures before serialization (and the other way after deserialization). However, the serializer in lldpd did not allow to handle reference to other structures, lists or circular references. I have written another one which works by annotating a structure with some macros:
struct lldpd_chassis  
    TAILQ_ENTRY(lldpd_chassis) c_entries;
    u_int16_t        c_index;
    u_int8_t         c_protocol;
    u_int8_t         c_id_subtype;
    char            *c_id;
    int              c_id_len;
    char            *c_name;
    char            *c_descr;
    u_int16_t        c_cap_available;
    u_int16_t        c_cap_enabled;
    u_int16_t        c_ttl;
    TAILQ_HEAD(, lldpd_mgmt) c_mgmt;
 ;
MARSHAL_BEGIN(lldpd_chassis)
MARSHAL_TQE  (lldpd_chassis, c_entries)
MARSHAL_FSTR (lldpd_chassis, c_id, c_id_len)
MARSHAL_STR  (lldpd_chassis, c_name)
MARSHAL_STR  (lldpd_chassis, c_descr)
MARSHAL_SUBTQ(lldpd_chassis, lldpd_mgmt, c_mgmt)
MARSHAL_END;
Only pointers need to be annotated. The remaining of the structure can be serialized with just memcpy()1. I think there is still room for improvement. It should be possible to add annotations inside the structure and avoid some duplication. Or maybe, using a C parser? Or using the AST output from LLVM?

Library In lldpd 0.5.7, there are two possible entry points to interact with the daemon:
  1. Through SNMP support. Only information available in LLDP-MIB are exported. Therefore, implementation-specific values are not available. Moreover, SNMP support is currently read-only.
  2. Through lldpctl. Thanks to a contribution from Andreas Hofmeister, the output can be requested to be formatted as an XML document.
Integration of lldpd into a network stack was therefore limited to one of those two channels. As an exemple, you can have a look at how Vyatta made the integration using the second solution. To provide a more robust solution, I have added a shared library, liblldpctl, with a stable and well-defined API. lldpctl is now using it. I have followed those directions2:
  • Consistent naming (all exported symbols are prefixed by lldpctl_). No pollution of the global namespace.
  • Consistent return codes (on errors, all functions returning pointers are returning NULL, all functions returning integers are returning -1).
  • Reentrant and thread-safe. No global variables.
  • One well-documented include file.
  • Reduce the use of boilerplate code. Don t segfault on NULL, accept integer input as string, provide easy iterators,
  • Asynchronous API for input/output. The library delegates reading and writing by calling user-provided functions. Those functions can yield their effects. In this case, the user has to callback the library when data is available for reading or writing. It is therefore possible to integrate the library with any existing event-loop. A thin synchronous layer is provided on top of this API.
  • Opaque types with accessor functions.
Accessing bits of information is done through atoms which are opaque containers of type lldpctl_atom_t. From an atom, you can extract some properties as integers, strings, buffers or other atoms. The list of ports is an atom. A port in this list is also an atom. The list of VLAN present on this port is an atom, as well as each VLAN in this list. The VLAN name is a NULL-terminated string living in the scope of an atom. Accessing a property is done by a handful of functions, like lldpctl_atom_get_str(), using a specific key. For example, here is how to display the list of VLAN assuming you have one port as an atom:
vlans = lldpctl_atom_get(port, lldpctl_k_port_vlans);
lldpctl_atom_foreach(vlans, vlan)  
    vid = lldpctl_atom_get_int(vlan,
                               lldpctl_k_vlan_id));
    name = lldpctl_atom_get_str(vlan,
                                lldpctl_k_vlan_name));
    if (vid && name)
        printf("VLAN %d: %s\n", vid, name);
 
lldpctl_atom_dec_ref(vlans);
Internally, an atom is typed and reference counted. The size of the API is greatly limited thanks to this concept. There are currently more than one hundred pieces of information that can be retrieved from lldpd. Ultimately, the library will also enable the full configuration of lldpd. Currently, many aspects can only be configured through command-line flags. The use of the library does not replace lldpctl which will still be available and be the primary client of the library.

CLI Having a configuration file was requested since a long time. I didn t want to include a parser in lldpd: I am trying to keep it small. It was already possible to configure lldpd through lldpctl. Locations, network policies and power policies were the three items that could be configured this way. So, the next step was to enable lldpctl to read a configuration file, parse it and send the result to lldpd. As a bonus, why not provide a full CLI accepting the same statements with inline help and completion?

Parsing & completion Because of completion, it is difficult to use a YACC generated parser. Instead, I define a tree where each node accepts a word. A node is defined with this function:
struct cmd_node *commands_new(
    struct cmd_node *,
    const char *,
    const char *,
    int(*validate)(struct cmd_env*, void *),
    int(*execute)(struct lldpctl_conn_t*, struct writer*,
        struct cmd_env*, void *),
    void *);
A node is defined by:
  • its parent,
  • an optional accepted static token,
  • an help string,
  • an optional validation function and
  • an optional function to execute if the current token is accepted.
When walking the tree, we maintain an environment which is both a key-value store and a stack of positions in the tree. The validation function can check the environment to see if we are in the right context (we want to accept the keyword foo only once, for example). The execution function can add the current token as a value in the environment but it can also pop the current position in the tree to resume walk from a previous node. As an example, see how nodes for configuration of a coordinate-based location are registered:
/* Our root node */
struct cmd_node *configure_medloc_coord = commands_new(
    configure_medlocation,
    "coordinate", "MED location coordinate configuration",
    NULL, NULL, NULL);
/* The exit node.
   The validate function will check if we have both
   latitude and longitude. */
commands_new(configure_medloc_coord,
    NEWLINE, "Configure MED location coordinates",
    cmd_check_env, cmd_medlocation_coordinate,
    "latitude,longitude");
/* Store latitude. Once stored, we pop two positions
   to go back to the "root" node. The user can only
   enter latitude once. */
commands_new(
    commands_new(
        configure_medloc_coord,
        "latitude", "Specify latitude",
        cmd_check_no_env, NULL, "latitude"),
    NULL, "Latitude as xx.yyyyN or xx.yyyyS",
    NULL, cmd_store_env_value_and_pop2, "latitude");
/* Same thing for longitude */
commands_new(
    commands_new(
        configure_medloc_coord,
        "longitude", "Specify longitude",
        cmd_check_no_env, NULL, "longitude"),
    NULL, "Longitude as xx.yyyyE or xx.yyyyW",
    NULL, cmd_store_env_value_and_pop2, "longitude");
The definition of all commands is still a bit verbose but the system is simple enough yet powerful enough to cover all needed cases.

Readline When faced with a CLI, we usually expect some perks like completion, history handling and help. The most used library to provide such features is the GNU Readline Library. Because this is a GPL library, I have first searched an alternative. There are several of them: From an API point of view, the first three libraries support the GNU Readline API. They also have a common native API. Moreover, this native API also handles tokenization. Therefore, I have developed the first version of the CLI with this API3. Unfortunately, I noticed later this library is not very common in the Linux world and is not available in RHEL. Since I have used the native API, it was not possible to fallback to the GNU Readline library. So, let s switch! Thanks to the appropriate macro from the Autoconf Archive (with small modifications), the compilation and linking differences between the libraries are taken care of. Because GNU Readline library does not come with a tokenizer, I had to write one myself. The API is also badly documented and it is difficult to know which symbol is available in which version. I have limited myself to:
  • readline(), addhistory(),
  • rl_insert_text(),
  • rl_forced_update_display(),
  • rl_bind_key()
  • rl_line_buffer and rl_point.
Unfortunately, the various libedit libraries have a noop for rl_bind_key(). Therefore, completion and online help is not available with them. I have noticed that most BSD come with GNU Readline library preinstalled, so it could be considered as a system library. Nonetheless, linking with libedit to avoid licensing issues is possible and help can be obtained by prefixing the command with help.

OS specific support

BSD support Until version 0.7, lldpd was Linux-only. The rewrite to use Netlink was the occasion to abstract interfaces and to port to other OS. The first port was for Debian GNU/kFreeBSD, then for FreeBSD, OpenBSD and NetBSD. They all share the same source code:
  • getifaddrs() to get the list of interfaces,
  • bpf(4) to attach to an interface to receive and send packets,
  • PF_ROUTE socket to be notified when a change happens.
Each BSD has its own ioctl() to retrieve VLAN, bridging and bonding bits but they are quite similar. The code was usually adapted from ifconfig.c. The BSD ports have the same functionalities than the Linux port, except for NetBSD which lacks support for LLDP-MED inventory since I didn t find a simple way to retrieve DMI related information. They also offer greater security by filtering packets sent. Moreover, OpenBSD allows to lock the filters set on the socket:
/* Install write filter (optional) */
if (ioctl(fd, BIOCSETWF, (caddr_t)&fprog) < 0)  
    rc = errno;
    log_info("privsep", "unable to setup write BPF filter for %s",
        name);
    goto end;
 
/* Lock interface */
if (ioctl(fd, BIOCLOCK, (caddr_t)&enable) < 0)  
    rc = errno;
    log_info("privsep", "unable to lock BPF interface %s",
        name);
    goto end;
 
This is a very nice feature. lldpd is using a privileged process to open the raw socket. The socket is then transmitted to an unprivileged process. Without this feature, the unprivileged process can remove the BPF filters. I have ported the ability to lock a socket filter program to Linux. However, I still have to add a write filter.

OS X support Once FreeBSD was supported, supporting OS X seemed easy. I got sponsored by xcloud.me which provided a virtual Mac server. Making lldpd work with OS X took only two days, including a full hour to guess how to get Apple Xcode without providing a credit card. To help people installing lldpd on OS X, I have also written a lldpd formula for Homebrew which seems to be the most popular package manager for OS X.

Upstart and systemd support Many distributions propose upstart and systemd as a replacement or an alternative for the classic SysV init. Like most daemons, lldpd detaches itself from the terminal and run in the background, by forking twice, once it is ready (for lldpd, this just means we have setup the control socket). While both upstart and systemd can accommodate daemons that behave like this, it is recommended to not fork. How to advertise readiness in this case? With upstart, lldpd will send itself the SIGSTOP signal. upstart will detect this, resume lldpd with SIGCONT and assume it is ready. The code to support upstart is therefore quite simple. Instead of calling daemon(), do this:
const char *upstartjob = getenv("UPSTART_JOB");
if (!(upstartjob && !strcmp(upstartjob, "lldpd")))
    return 0;
log_debug("main", "running with upstart, don't fork but stop");
raise(SIGSTOP);
The job configuration file looks like this:
# lldpd - LLDP daemon
description "LLDP daemon"
start on net-device-up IFACE=lo
stop on runlevel [06]
expect stop
respawn
script
  . /etc/default/lldpd
  exec lldpd $DAEMON_ARGS
end script
systemd provides a socket to achieve the same goal. An application is expected to write READY=1 to the socket when it is ready. With the provided library, this is just a matter of calling sd_notify("READY=1\n"). Since sd_notify() has less than 30 lines of code, I have rewritten it to avoid an external dependency. The appropriate unit file is:
[Unit]
Description=LLDP daemon
Documentation=man:lldpd(8)
[Service]
Type=notify
NotifyAccess=main
EnvironmentFile=-/etc/default/lldpd
ExecStart=/usr/sbin/lldpd $DAEMON_ARGS
Restart=on-failure
[Install]
WantedBy=multi-user.target

OS include files Linux-specific include files were a major pain in previous versions of lldpd. The problems range from missing header files (like linux/if_bonding.h) to the use of kernel-only types. Those headers have a difficult history. They were first shipped with the C library but were rarely synced and almost always outdated. They were then extracted from kernel version with almost no change and lagged behind the kernel version used by the released distribution4. Today, the problem is acknowledged and is being solved by both the distributions which extract the headers from the packaged kernel and by kernel developers with a separation of kernel-only headers from user-space API headers. However, we still need to handle legacy. A good case is linux/ethtool.h:
  • It can just be absent.
  • It can use u8, u16 types which are kernel-only types. To work around this issue, type munging can be setup.
  • It can miss some definition, like SPEED_10000. In this case, you either define the missing bits and find yourself with a long copy of the original header interleaved with #ifdef or conditionally use each symbol. The latest solution is a burden by itself but it also hinders some functionalities that can be available in the running kernel.
The easy solution to all this mess is to just include the appropriate kernel headers into the source tree of the project. Thanks to Google ripping them for its Bionic C library, we know that copying kernel headers into a program does not create a derivative work.

  1. Therefore, the use of u_int16_t and u_int8_t types is a left-over of the previous serializer where the size of all members was important.
  2. For more comprehensive guidelines, be sure to check Writing a C library.
  3. Tokenization is not the only advantage of libedit native API. The API is also cleaner, does not have a global state and has a better documentation. All the implementations are also BSD licensed.
  4. For example, in Debian Sarge, the Linux kernel was a 2.6.8 (2004) while the kernel headers were extracted from some pre-2.6 kernel.

6 November 2012

Rapha&#235;l Hertzog: My Free Software Activities in October 2012

This is my monthly summary of my free software related activities. If you re among the people who made a donation to support my work (120.46 , thanks everybody!), then you can learn how I spent your money. Otherwise it s just an interesting status update on my various projects. Dpkg At the start of the month, I reconfigured dpkg s git repository to use KGB instead of the discontinued CIA to send out commit notices to IRC (on #debian-dpkg on OFTC, aka irc.debian.org). I didn t do anything else that affects dpkg and I must say that Guillem does not make it easy for others to get involved. He keeps all his work hidden in his private for 1.17.x branch and refuses to open an official jessie branch as can be seen from the lack of answer to this mail. On the bright side, he deals with almost all incoming bugs even before I have a chance to take care of them. But it s a pity that I can never review any of his fixes because they are usually pushed shortly before an upload. Misc packaging I helped to get #689336 fixed so that the initrd properly setups the keymap before asking for a passphrase for an encrypted partition. Related to this I filed #689722 so that cryptsetup gains a dependency ensuring that the required tools for keymap setup are available. I packaged a new upstream version of zim (0.57) and also a security update for python-django that affected both Squeeze and Wheezy. I uploaded an NMU of revelation (0.4.13-1.2) so that it doesn t get dropped from Wheezy (it was on the release team list of leaf packages that would be removed if unfixed) since my wife is using it to store her passwords. I sponsored a new upstream version of ledgersmb. Debian France We managed to elect new officers for Debian France. I m taking over the role of president, Sylveste Ledru is the new treasurer and Julien Danjou is the new secretary. Thank you very much to the former officers: Carl Chenet, Aur lien Jarno and Julien Cristau. We re in the process of managing this transition which will be completed during the next mini-Debconf in Paris so that we can exchange some papers and the like. In the first tasks that I have set myself, there s recruiting two new members for the boards of directors since we re only 7 and there are 9 seats. I made a call for volunteers and we have two volunteers. If you want to get involved and help Debian France, please candidate by answering that message as soon as possible. The Debian Handbook I merged the translations contributed on debian.weblate.org (which led me to file this wishlist bug on Weblate itself) and I fixed a number of small issues that had been reported. I made an upload to Debian to incorporate all those fixes But this is still the book covering Squeeze so I started to plan the work to update it for Wheezy and with Roland we have decided who is going to take care of updating each chapter. Librement Progress is annoyingly slow on this project. Handling money for others is highly regulated, at least in the EU apparently. I only wanted an escrow account to secure the money of users of the service but opening this account requires either to be certified as a payment institution by the Autorit de contr le prudentiel or to get an exemption from the same authority (covering only some special cases) or to sign a partnership with an established payment institution. Being certified is out of scope for now since it requires a minimum of 125000 EUR in capital (which I don t have). My bank can t sign the kind of partnership that I would need. So I have to investigate whether I can make it fit in the limited cases of exemption or I need to find another payment institution that is willing to work with me. Gittip uses Balanced a payment service specialized in market places but unfortunately it s US-only if you want to withdraw money from the system. I would love a similar service in Europe If I can t position Librement as a market place for the free software world (and save each contributor the hassle to open a merchant account), then I shall fallback to the solution where Librement only provides the infrastructure but no account, and developers who want to collect donations will have to use either Paypal or any other supported merchant account to collect funds. That s why my latest spec updates concerning the donation service and the payment service mentions Paypal and the possibility of choosing your payment service for your donation form. Thanks See you next month for a new summary of my activities.

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21 October 2012

Gregor Herrmann: RC bugs 2012/42

as zack has mentioned earlier today, the count of RC bugs is falling. & the release team is again proposing RC buggy packages for removal from testing.

these were my RC bug related activities during the last week:

13 October 2012

Johannes Schauer: Does it become harder to bootstrap Debian?

My last post explained how I retrieved and corrected data from snapshot.debian.org so that dose3 was able to parse it. In this post I will cover some surprising results I found when using my tools on those Packages and Sources files from 2005 until today. For each pair of Packages and Sources files I did the following:
  1. created a reduced distribution
  2. calculated the dependency graph
I call a reduced distribution the smallest set of binary and source packages with the following properties: Creating a reduced distribution first, greatly increases the execution speed of my algorithms as it reduces the amount of binary and source packages by an order of magnitude while still preserving the dependency cycle situation of the core packages. In many cases, once the packages of a reduced distribution are available, all the rest of Debian can be compiled from them without any dependency cycles. As also mentioned in earlier posts, there is always one central, big strongly connected component (SCC) in the dependency graph. I am especially interested in how the size of the reduced distribution and the SCC change over time as both are an indication of: Lets look at the plots I did from the data I gathered. The gray data points indicate that at that point in time, one or more of the core source packages (the ones in the reduced distribution) in Debian Sid was not compilable. This means that the resulting values cannot be fully trusted. But as it is mostly only a single source package that doesnt compile, it doesnt influence the overall result much and therefor I included them anyways. Red and green data points represent a fully successful run. The only thing that I do not yet understand is what happened in 2007... So while a potential porter in 2005 only had to look at a graph of 150 nodes, he now needs to solve a graph of nearly 1000 nodes. The amount of edges in the dependency graph grew even more dramatic from about 500 to over 8000 edges. While the dependency situation for Debian Sid in 2005 can easily be printed using xdot and visually solved, this in not possible anymore in 2012. While dependencies of only a few dozen source packages had to manually be dropped in 2005, now even dropping build dependencies from a few hundred source packages doesnt solve the dependency situation. So my assumption is, that due to a growing amount of interdependencies between source and binary packages (as both gain more features), bootstrapping Debian for a new architecture becomes harder over time. Is this also the perceived subjective impression of people that ported Debian in the past? If my assumption is correct, then there is a growing need for official support of droppable build dependencies (or "stage builds" or "profile builds") to break dependency cycles during the bootstrapping process. Work of a porter would be much easier if source packages would already contain information about what build dependencies can be dropped (if so needed). In the best case, a machine could use those annotations to calculate a build order automatically. As one can see in the graph above, there are currently 370 source packages in the main SCC. This means that no more than this amount of packages (but probably much less) have to be annotated to break the SCC into a directed acyclic graph. Discussion about what syntax to use to mark potentially droppable build dependencies currently happens in bug#661538 but should maybe be discussed by a wider audience. The currently favored solution was proposed in said bugreport by Guillem Jover and is called "build profiles". It has the advantage that it is not only trivial to implement (a patch exist for dpkg and dose3 already supports them) but would also be useful for other purposes like embedded builds. The format is similar to how architecture restrictions for individual dependencies are specified but uses "triangular brackets":
Build-Depends: huge (>= 1.0) [i386 arm] <!embedded !bootstrap>, tiny
The work Patrick McDermott did for his GSoC project over the summer already uses above syntax.

5 September 2012

Rapha&#235;l Hertzog: My Debian Activities in August 2012

This is my monthly summary of my Debian related activities. If you re among the people who made a donation to support my work (88.41 , thanks everybody!), then you can learn how I spent your money. Otherwise it s just an interesting status update on my various projects. This month has again been a short one since I have mostly been in vacation during the last 2 weeks. Dpkg Things are relatively quiet during the freeze. I only took care of fixing 3 bugs: a regression of 3.0 (quilt) (#683547), a segfault of dpkg-query -W -f (commit) and a bad auto-completion for French users (#685863). Testing the upgrade to wheezy We got several reports of wheezy upgrade that failed because dpkg ran the trigger while the dependencies of the package with pending triggers are not satisfied. Unfortunately fixing this in dpkg is not without problems (see #671711 for details) so Guillem decided to defer this fix for Jessie. My suggestion of an intermediary solution has fallen in limbo. Instead we now have to find solutions for each case where this can fail (example of failure: 680626). Another way to avoid those errors is to ensure that triggers are run as late as possible. We can improve this in multiple ways. The first way is to modify most triggers so that they use the interest-noawait directive. In that case, the packages activating the trigger will be immediately marked as configured (instead of triggers-awaited ) and the trigger will thus not need to be run as part of further dependency solving logic. But as of today, there s no package using this new feature yet despite a nudge on debian-devel-announce. :-( The second way is to modify APT to use dpkg no-triggers, and to let the trigger processing for the end (with a last dpkg configure -a call). I requested this early in the wheezy timeframe but for various reasons, the APT maintainers did not act on it. I pinged them again in #626599 but it s now too late for wheezy. I find this a bit sad because I have been using those options for the entire wheezy cycle and it worked fine for me (and I used them for a dist-upgrade on my wife s laptop too). It would have been good to have all this in place for wheezy so that we don t have to suffer from the same problems during the jessie upgrade, but unless someone steps up to steer those changes, it seems unlikely to happen. Instead, we re back to finding klumsy work-arounds in individual packages. Packaging I prepared security updates for python-django (1.4.1 for unstable,
1.2.3-3+squeeze3 for stable). I packaged a new upstream version for cpputest (3.2-1). I reviewed ledgersmb 1.3.21-1 prepared by Robert James Clay and asked him to prepare another version with further fixes. I released nautilus-dropbox 1.4.0-2 with supplementary changes of my own to support https_proxy and to display better diagnostic information when the download fails. With the help of Paul van der Vlis and Michael Ziegler, we did what was required to be able to migrate python-django-registration 0.8 to Wheezy even though it s a new upstream version with backwards incompatible changes. Thanks to Adam D. Barratt who unblocked the package, we now have the right version in Wheezy despite the fact that I missed the freeze deadline. Debian France Julien Cristau reminded the board of Debian France that we have to elect officers (President, Secretary, Treasurer) as the current officers have withdrawn. I was somewhat afraid that nobody would take over so I pinged each member to try to get new volunteers. We now have volunteers (me, Julien Danjou and Sylvestre Ledru) and we re waiting until Julien finds some time to run the election. Misc With the help of DSA, I setup antispam rules for the owner@packages.qa.debian.org alias because I was getting tired by the amount of spam. In the process, they asked me to write a wiki page for dsa.debian.org to document everything so that they can refer to it for future queries. I did it but it looks like that they did not apply my patch yet. I also tested an upstream patch for gnome-keyring (see bugzilla #681081) that reintroduces the support of forgetting GPG passphrases after a specified amount of time. Thanks See you next month for a new summary of my activities.

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13 August 2012

Rapha&#235;l Hertzog: Looking back at 16 years of dpkg history with some figures

With Debian s 19th anniversary approaching, I thought it would be nice to look back at dpkg s history. After all, it s one of the key components of any Debian system. The figures in this article are all based on dpkg s git repository (as of today, commit 9a06920). While the git repository doesn t have all the history, we tried to integrate as much as possible when we created it in 2007. We have data going back to April 1996 In this period between April 1996 and August 2012: Currently the dpkg source tree contains 28303 lines of C, 14956 lines of Perl and 6984 lines of shell (figures generated by David A. Wheeler s SLOCCount ) and is translated in 40 languages (but very few languages managed to translate everything, with all the manual pages there are 3997 strings to translate). The top 5 contributors of all times (in number of commits) is the following (result of git log --pretty='%aN' sort uniq -c sort -k1 -n -r head -n 5):
  1. Guillem Jover with 2663 commits
  2. Rapha l Hertzog with 993 commits
  3. Wichert Akkerman with 682 commits
  4. Christian Perrier with 368 commits
  5. Adam Heath with 342 commits
I would like to point out that those statistics are not entirely representative as people like Ian Jackson (the original author of dpkg s C reimplementation) or Scott James Remnant were important contributors in parts of the history that were recreated by importing tarballs. Each tarball counts for a single commit but usually bundles much more than one change. Also each contributor has its own habits in terms of crafting a work in multiple commits. Last but not least, I have generated this 3 minutes gource visualization of dpkg git s history (I used Planet s head pictures for dpkg maintainers where I could find it). <iframe allowfullscreen="allowfullscreen" frameborder="0" height="281" src="http://www.youtube.com/embed/1x9-Etj1Ew4?fs=1&amp;feature=oembed" width="500"></iframe> Watching this video made me realize that I have been contributing to dpkg for 5 years already. I m looking forward to the next 5 years :-) And what about you? You could be the 147th contributor see this wiki page to learn more about the team and to start contributing.

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8 August 2012

Johannes Schauer: Bootstrappable Debian - How to help

TLDR: multiarch, multiarch, multiarch, cross buildability, staged build dependencies, wiki page, corrections/hints/requests to debian-bootstrap at lists.mister-muffin.de This summer (and this year's GSoC) is nearing its end and to make it easier for people to make use of the information my tools produced so far, I created a page in the Debian wiki. It lists not only the open issues I see but also statistics that I gathered using the output of my GSoC project. I want to use this blog post to make people aware of that page as well as to get some feedback on it and anything related to it. The biggest blocker my tools face, is that many packages are still missing multiarch information. As long as at least the basic packages do not have their cross build dependencies satisfied via multiarch for an existing foreign architecture, automated tools can not properly analyze the dependency situation in the bootstrapping case, when many packages of the new foreign architecture do not even exist yet. If Debian is supposed to be bootstrappable, then the first stage is to make a set of basic packages cross compile for an existing foreign architecture. Once this is possible, a tool of mine can analyze the cyclic build dependency situation that might occur when cross compiling for an architecture that does not exist yet. Then, staged cross builds can be used to cross compile a minimal foreign system. Due to missing multiarch classification, it is not known yet how big the cyclic build dependency situation is for the base packages. It is not only the conversion of packages to multiarch that is needed but also the adding of the :any (and rare cases :native) qualifier to build dependencies on M-A: allowed packages. Prominent build dependencies that should (but are not yet) be M-A: allowed are python and gettext. Both are needed as a build dependency by many packages of the base system. Unfortunately wanna-build does not understand qualifiers like :any and :native yet. Until it does, no package can be marked :any or :native and cross compilation of many base packages can not succeed. Once the point is reached, where a base system can be cross compiled from nothing, native compilation can start. Since native compilation doesnt depend on multiarch, the dependency situation when trying to natively compiling all of Debian from nothing is understood much better. Unfortunately, the cyclic build dependency situation is also much worse in the native case and there exists a big 1000 node strongly connected component of binary and source packages that all interdepend on each other. This dependency mess can be solved using three approaches: The wiki page gives many hints on how to find packages that each method can be applied to. Stage building is a tool that might be useful for cross building (we dont know for sure yet) but is definitely needed for native compilation. It is needed for native compilation because after all possible dependencies are moved to Build-Depends-Indep, the only other alternative to stage building for breaking dependency cycles is to cross build source packages. Since building a package without one of its build dependencies "staged" is often much easier than making the package in question cross compile, it is a preferred alternative. Once more packages have been made multiarch, it might be possible to prove that there is no alternative to introducing a notion of staged builds. Some people (wookey, Patrick McDermott, Guillem Jover, myself) decided that the following format to mark staged build dependencies would be preferred over others:
Build-Depends: huge (>= 1.0) [i386 arm] <!embedded !bootstrap>, tiny
The <> format was proposed by Guillem Jover in bug#661538. Patches for dpkg and dose3 are done. More people need to discuss about this format for a final decision on how to indicate staged build dependencies. For more information on the topic, have a look at the corresponding wiki page. Feel free to direct any comments/critique/hints to debian-bootstrap at lists.mister-muffin.de or directly to me.

1 August 2012

Rapha&#235;l Hertzog: My Debian Activities in July 2012

This is my monthly summary of my Debian related activities. If you re among the people who made a donation to support my work (72.65 , thanks everybody!), then you can learn how I spent your money. Otherwise it s just an interesting status update on my various projects. This month has been a short one since I have been away for 2 weeks of vacation. Dpkg My dpkg work encompasses a bunch of small tasks: Packaging I updated nautilus-dropbox to version 1.4.0 and python-django-registration to version 0.8. Both have been uploaded to unstable and I initially wanted to request an unblock for the latter, but it turns out it has gained reverse dependencies and version 0.8 introduces API changes so it s not an option at this point of the freeze. QA work I investigated and fixed #678356 where it had been reported that the PTS static news were no longer working as expected. At the start of the month, I also unblocked the mostly-unknown but important mole service it was out of date of several weeks and several people were annoyed that the information about new upstream versions was no longer up-to-date. Vacation Almost no Debian work during my vacation but the lack of Wifi nearby made me look for solutions to connect my computer through my Nokia N900 3G/GPRS connection. I discovered the Mobile Hotspot application (homepage) and it worked like a charm (although it required Maemo s non-default devel repository to be able to install the alternative kernel for power users ). The Debian Handbook Michal iha proposed us to host a Weblate instance to help translate the book with a web interface. He kindly agreed to implement some improvements to better suit my requirements. Those have been completed and the weblate instance is now live at debian.weblate.org. There s no requirement to use Weblate for translations teams but for those that do, it sure makes it easier to recruit volunteers who have no prior knowledge of Git and PO files. If you want to help, please checkout this page first though, you should not start using Weblate without getting in touch with the respective translations teams. Apart from translations, I also had the pleasure to merge some patches from Philipp Kern who improved the section covering IPv6 and a few other parts. We can make the book even better if more people share their expertise in the part of the book where they know better than me and Roland. :-) Thanks See you next month for a new summary of my activities.

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30 July 2012

Johannes Schauer: port bootstrap build-ordering tool report 4

A copy of this post is sent to soc-coordination@lists.alioth.debian.org as well as to debian-bootstrap@lists.mister-muffin.de.

Diary

July 2
  • playing around with syntactic dependency graphs and how to use them to flatten dependencies

July 4
  • make work with dose 3.0.2
  • add linux-amd64 to source architectures
  • remove printing in build_compile_rounds
  • catch Not_found exception and print warning
  • use the whole installation set in crosseverything.ml instead of flattened dependencies
  • detect infinite loop and quit in crosseverything.ml
  • use globbing in _tags file
  • use wildcards and patsubst in makefile

July 5
  • throw a warning if there exist binary packages without source packages
  • add string_of_list and string_of_pkglist and adapt print_pkg_list and print_pkg_list_full to use them
  • fix and extend flatten_deps - now also tested with Debian Sid

July 6
  • do not exclude the crosscompiled packages from being compiled in crosseverything.ml
  • clean up basebuildsystem.ml, remove old code, use BootstrapCommon code
  • clean up basenocycles.ml, remove unused code and commented out code
  • add option to print statistics about the generated dependency graph
  • implement most_needed_fast_wrong as well as most_needed_slow_correct and make both available through the menu

July 7
  • allow to investigate all scc, not only the full graph and the scc containing the investigated package
  • handle Not_found in src_list_from_bin_list with warning message
  • handle the event of the whole archive actually being buildable
  • replace raise Failure with failwith
  • handle incorrectly typed package names
  • add first version of reduced_dist.ml to create a self-contained mini distribution out of a big one

July 8
  • add script to quickly check for binary packages without source package
  • make Debian Sid default in makefile
  • add *.d.byte files to .gitignore
  • README is helpful now
  • more pattern matching and recursiveness everywhere

July 9
  • fix termination condition of reduced_dist.ml
  • have precise as default ubuntu distribution
  • do not allow to investigate an already installable package

July 10
  • milestone: show all cycles in a graph
  • add copyright info (LGPL3+)

July 11
  • advice to use dose tools in README

July 16
  • write apt_pkg based python filter script replacing grep-dctrl

July 17
  • use Depsolver.listcheck more often
  • add dist_graph.ml
  • refactor dependency graph code into its own module

July 18
  • improve package selection for reduced_dist.ml
  • improve performance of cycle enumeration code

July 20
  • implement buildprofile support into dose3

July 22
  • let dist_graph.ml use commandline arguments

July 23
  • allow dose3 to generate source package lists without Build- Depends Conflicts -Indep

July 29
  • implement crosscompile support into dose3

Results

Readme There is not yet a writeup on how everything works and how all the pieces of the code work together but the current README file provides a short introduction on how to use the tools.
  • build and runtime dependencies
  • compile instructions
  • execution examples for each program
  • step by step guide how to analyze the dependency situation
  • explanation of general commandline options
A detailed writeup about the inner workings of everything will be part of a final documentation stage.

License All my code is now released under the terms of the LGPL either version 3, or (at your option) any later version. A special linking exception is made to the license which can be read at the top of the provided COPYING file. The exception is necessary because Ocaml links statically, which means that without that exception, the conditions of distribution would basically equal GPL3+.

reduced_dist.ml Especially the Debian archive is huge and one might want to work on a reduced selection of packages first. Having a smaller selection of the archive would be significantly faster and would also not add thousands of packages that are not important for an extended base system. I call a reduced distribution a set of source packages A and a set of binary packages B which fulfill the following three properties:
  • all source packages A must be buildable with only binary packages B being available
  • all binary packages B except for architecture:all packages must be buildable from source packages A
The set of binary packages B and source packages A can be retrieved using the reduced_dist program. It allows to either build the most minimal reduced distribution or one that includes a certain package selection. To filter out the package control stanzas for a reduced distribution from a full distribution, I originally used a call to grep-dctrl but later replaced that by a custom python script called filter-packages.py. This script uses python-apt to filter Packages and Sources files for a certain package selection.

dist_graph.ml It soon became obvious that there were not many independent dependency cycle situation but just one big scc that would contain 96% of the packages that are involved in build dependency cycles. Therefor it made sense to write a program that does not iteratively build the dependency graph starting from a single package, but which builds a dependency graph for a whole archive.

Cycles I can now enumerate all cycles in the dependency graph. I covered the theoretical part in another blog post and wrote an email about the achievement to the list. Both resources contain more links to the respective sourcecode. The dependency graph generated for Debian Sid has 39486 vertices. It has only one central scc with 1027 vertices and only eight other scc with 2 to 7 vertices. All the other source and binary packages in the dependency graph for the archive are degenerate components of length one. Obtaining the attached result took 4 hours on my machine (Core i5 @ 2.53GHz). 1.5 h of that were needed to build the dependency graph, the other 2.5 hours were needed to run johnson's algorithm on the result. Memory consumption of the program was at about 700 MB. It is to my joy that apparently the runtime of the cycle finding algorithm for a whole Debian Sid repository as well as the memory requirements are within orders of magnitude that are justifiable when being run on off-the-shelf hardware. It must also be noted that nothing is optimized for performance yet. A list of all cycles in Debian Sid up to length 4 can be retrieved from this email. This cycle analysis assumes that only essential packages, build-essential and dependencies and debhelper are available. Debhelper is not an essential or build-essential package but 79% of the archive build-depends on it. The most interesting cycles are probably those of length 2 that need packages that they build themselves. Noticeable examples for these situations are vala, python, mlton, fpc, sbcl and ghc. Languages seem love to need themselves to be built.

Buildprofiles There is a long discussion of how to encode staged build dependency information in source packages. While the initial idea was to use Build-Depends-StageN fields, this solution would duplicate large parts of the Build-Depends field, which leads to bitrot as well as it is inflexible to possible other build "profiles". To remedy the situation it was proposed to use field names like Build-Depends[stage1 embedded] but this would also duplicate information and would break with the rfc822 format of package description files. A document maintained by Guillem Jover gives even more ideas and details. Internally, Patrick and me decided for another idea of Guillem Jover to annotate staged build dependencies. The format reads like:
Build-Depends: huge (>= 1.0) [i386 arm] <!embedded !bootstrap>, tiny
So each build profile would follow a dependency in <> "brackets" an have a similar format as architecture options. Patrick has a patch for dpkg that implements this functionality while I patched dose3.

Dropping Build-Depends-Indep and Build-Conflicts-Indep When representing the dependencies of a source package, dose3 concatenates its Build-Depends and Build-Depends-Indep dependency information. So up to now, a source package could only be compiled, if it manages to compile all of its binary packages including architecture:all packages. But when bootstrapping a new architecture, it should be sufficient to only build the architecture dependent packages and therefor to only build the build-arch target in debian/rules and not the build-indep target. Only considering the Build-Depends field and dismissing the Build-Depends-Indep field, reduced the main scc from 1027 vertices to 979 vertices. The amount of cycles up to length four reduced from 276 to 206. Especially the cycles containing gtk-doc-tools, doxygen, debiandoc-sgml and texlive-latex-base got much less. Patrick managed to add a Build-Depends-Indep field to four packages so far which reduced the scc further by 14 vertices down to 965 vertices. So besides staged build dependencies and cross building there is now a third method that can be applied to break dependency cycles: add Build-Depends-Indep information to them or update existing information. I submitted a list of packages that have a binary-indep and/or a build-indep target in their debian/rules to the list. I also submitted a patch for dose3 to be able to specify to ignore Build-Depends-Indep and Build-Conflicts-Indep information.

Dose3 crossbuilding So far I only looked at dependency situations in the native case. While the native case contains a huge scc of about 1000 packages, the dependency situation will be much nicer when cross building. But dose3 was so far not able to simulate cross building of source packages. I wrote a patch that implements this functionality and will allow me to write programs that help analyze the cross-situation as well.

Debconf Presentation Wookey was giving a talk at debconf12 for which I was supplying him with slides. The slides in their final version can be downloaded here

Future Patrick maintains a list of "weak" build dependencies. Those are dependencies that are very likely to be droppable in either a staged build or using Build-Depends-Indep. I must make use of this list to make it easier to find packages that can easily be removed of their dependencies. I will have to implement support for resolving the main scc using staged build dependencies. Since it is unlikely that Patrick will be fast enough in supplying me with modified packages, I will need to create myself a database of dummy packages. Another open task is to allow to analyze the crossbuilding dependency situation. What I'm currently more or less waiting on is the inclusion of my patches into dose3 as well as a decision on the buildprofile format. More people need to discuss about it until it can be included into tools as well as policy. Every maintainer of a package can help making bootstrapping easier by making sure that as many dependencies as possible are part of the Build-Depends-Indep field.

6 July 2012

Christian Perrier: Debcamp work

It's still good to be at Debcamp before DebConf and I'm not running all day long, contrary to what you might think by reading my posts. Of course, I'm always busy with "social-like" activities such as doing my best for us to have a good Cheese and Wine Party as, now that I'm trapped into it, people expect it to be better and better each year. Or to revive the traditional Assassins game. But Debian is not only about killing cheese with socks and I try to also achieve a few things while being here. As of now, I can already count a few things: The only thing I nearly haven't worked on yet is....the talk I have on Sunday and that is supposed to explain newcomers how to join the crowd of localization fanatics. Oh, and I'm still jetlagged and go to bed daily at 10pm...:-)

1 May 2012

Rapha&#235;l Hertzog: My Debian Activities in April 2012

This is my monthly summary of my Debian related activities. If you re among the people who made a donation to support my work (186.38 , thanks everybody!), then you can learn how I spent your money. Otherwise it s just an interesting status update on my various projects. Dpkg News For the first time since several years, there has been a dpkg release (1.16.3) where the changelog doesn t contain any entry of my own. The 3-4 commits I did were not really worthy of a changelog entry. I must admit that it was easy to put dpkg aside given Guillem s message and given how busy I have been with my other projects. Keeping a low-profile for a while certainly doesn t hurt. But I don t intend to stop contributing to dpkg. Quite on the contrary in fact, it s something that I (usually) enjoy doing. Packaging News I packaged a new upstream release of SQL-Ledger (3.0.0) and later in the month I sponsored the upload of LedgerSMB, a fork of SQL-Ledger which unlike the former is maintained like a typical free software project. I also uploaded version 0.56 of Zim and updated WordPress to version 3.3.2 with its slew of security fixes. The Debian Administrator s Handbook Like several months now, most of my time has been directed towards the Debian Administrator s Handbook. The big news is that the liberation fund has been completed this means that the book will be published under DFSG-free licenses from the start (GPL-2+ / CC-BY-SA 3.0). We hope to publish the book next week (i.e. between May 7th and May 11th). The PDF output for the printed book is almost ready. There s some work left for the HTML/EPUB output and we have to prepare for the release of the sources as well Hopefully everything will work out like planned. Stay tuned! Thanks See you next month for a new summary of my activities.

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1 April 2012

Rapha&#235;l Hertzog: My Debian Activities in March 2012

This is my monthly summary of my Debian related activities. If you re among the people who made a donation to support my work (227.83 , thanks everybody!), then you can learn how I spent your money. Otherwise it s just an interesting status update on my various projects. Dpkg Thanks to Guillem, dpkg with multiarch support is now available in Debian sid. The road has been bumpy, and it has again been delayed multiple times even after Guillem announced it on debian-devel-announce. Finally, the upload happened on March 19th. I did not appreciate his announce because it was not coordinated at all, and had I been involved from the start, we could have drafted it in a way that sounded less scary for people. In the end, I provided a script so that people can verify whether they were affected by one of the potential problems that Guillem pointed out. While real, most of them are rather unlikely for typical multiarch usage. Bernhard R. Link submitted a patch to add a new status command to dpkg-buildflags. This command would print all the information required to understand which flags are activated and why. It would typically be called during the build process by debian/rules to keep a trace of the build flags configuration. The goal is to help debugging and also to make it possible to extract that information automatically from build logs. I reviewed his patch and we made several iterations, it s mostly ready to be merged but there s one detail where Bernhard and I disagree and I solicited Guillem s opinion to try to take a decision. Unfortunately neither Guillem nor anyone else chimed in. On request of Alexander Wirt, I uploaded a new backport of dpkg where I dropped the DEB_HOST_MULTIARCH variable from dpkg-architecture to ensure multi-arch is never accidentally enabled in other backports. One last thing that I did not mention publicly at all yet, is that I contacted Lennart Poettering to suggest an improvement to the /etc/os-release file that he s trying to standardize across distributions. It occurred to me that this file could also replace our /etc/dpkg/origins/default file (and not only /etc/debian_version) provided that it could store ancestry information. After some discussions, he documented new official fields for that file (ID_LIKE, HOME_URL, SUPPORT_URL, BUG_REPORT_URL). Next step for me is to improve dpkg-vendor to support this file (as a fallback or as default, I don t know yet). Packaging I packaged quilt 0.60 (we re now down to 9 Debian-specific patches, from a whopping 26 in version 0.48!) and zim 0.55. In prevision of the next upstream version of Publican, I asked the Perl team to package a few Perl modules that Publican now requires. Less than two weeks after, all of them were in Debian Unstable. Congrats and many thanks to the Perl team (and Salvatore Bonaccorso in particular, which I happen to know because we were on the same plane during last Debconf!). On a side note, being the maintainer of nautilus-dropbox became progressively less fun over the last months, in particular because the upstream authors tried to override some of the (IMO correct) packaging decisions that I made and got in touch with Ubuntu community managers to try to have their way. Last but not least, I keep getting duplicates of a bug that is not in my package but in the official package and that Dropbox did not respond to my query. Book update The translation is finished and we re now reviewing the whole book. It takes a bit more time than expected because we re trying to harmonize the style and because it s difficult to coordinate the work of several volunteer reviewers. The book cover is now almost finalized (click on it to view it in higher definitions): We also made some progress on the interior design for the paperback. Unfortunately, I have nothing to show you yet. But it will be very nice and made with just a LaTeX stylesheet tailored for use with dblatex. The liberation fundraising slowed down with only 41 new supporters this month but it made a nice bump anyway thanks to a generous donation of 1000 EUR by Offensive security, the company behind Backtrack Linux. They will soon communicate on this, hopefully it will boost the operation. It would be really nice if we managed to raise the remaining 3000 EUR in the few weeks left until the official release of the book! The work on my book dominated the month and explains my relative inactivity on other fronts. I worked much more than usual, and my wife keeps telling me that I look tired and that I should go in bed earlier but I see the end of the tunnel: if everything goes well, the book should be released in a few weeks and I will be able to switch back to a saner lifestyle. Thanks See you next month for a new summary of my activities.

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1 March 2012

Rapha&#235;l Hertzog: My Debian Activities in February 2012

This is my monthly summary of my Debian related activities. If you re among the people who made a donation to support my work (384.14 , thanks everybody!), then you can learn how I spent your money. Otherwise it s just an interesting status update on my various projects. Dpkg and multiarch The month started with a decision of the technical committee which allowed me to proceed with an upload of a multiarch dpkg even if Guillem had not yet finished his review (and related changes). Given this decision, Guillem made the experimental upload himself. I announced the availability of this test version and invited people to test it. This lead to new discussions on debian-devel. We learned in those discussions that Guillem changed his mind about the possibility of sharing (identical) files between multiple Multi-Arch: same packages, and that he dropped that feature. But if this point of the multiarch design had been reverted, it would mean that we had to update again all library packages which had already been updated for multi-arch. The discussions mostly stalled at this point with a final note of Guillem explaining that there was a tension between convenience and doing the right things every time that we discuss far-reaching changes. After a few weeks (and a helpful summary from Russ Allbery), Guillem said that he remained unconvinced but that he put back the feature. He also announced that he s close to having completed the work and that he would push the remaining parts of the multiarch branch to master this week (with the 1.16.2 upload planned next week). That s it for the summary. Obviously I participated in the discussions but I didn t do much besides this I have a mandate to upload a multiarch dpkg to sid but I did not want to make use of it while those discussions remained pretty unconclusive. Also Guillem made it pretty clear that the multiarch implementation was buggy , not right and not finished and that he had reworked code fixing at least some of the issues since he never shared that work in progress, I also had no way to help even just by reviewing what he s doing. We also got a few multiarch bug reports, but I couldn t care to get them fixed since Guillem clearly held a lock on the codebase having done many private changes it s not quite like this that I expect to collaborate on a free software project but life is full of surprises! I ll be relieved once this story is over. In the mean time, I have added one new thing on my TODO list since I made a proposal to handle bin-nmu changelogs and it s something that could also fix #440094. Misc dpkg stuff After a discussion with Guillem, we agreed that copyright notices should only appear in the sources and not in manual pages or --version output, both of which are translated and cause useless work to translators when updated. Guillem already had some code to do it for --version strings, and I took care of the changes for the manual pages. I merged some minor documentation updates, fixed a bug with a missing manpage. Later I discovered that some recent changes lead to the loss of all the translated manual pages. I suggested an improvement to dh_installman to fix this (and even prepared a patch). In the end, Guillem opted for another way of installing translated manual pages. Triggered by a discussion on debian-devel, I added a new entry to my TODO list: implementing dpkg-maintscript-helper rm_conffile_if_owner to deal with the case where a conffile is taken over by another package which might (or might not) be installed. Misc packaging At the start of the month, I packaged quilt 0.51. The number of Debian specific patches is slowly getting down. With version 0.51, we dropped 5 patches and introduced a new one. Later in the month I submitted 4 supplementary patches upstream which have been accepted for version 0.60. This new version (just released, I will package it soon) is an important milestone since it s the first version without any C code (Debian had this for a long time but we were carrying an intrusive patch for this). Upstream developer Jean Delvare worked on this and based his work on our patch, but he went further to make it much more efficient. Besides quilt, I also uploaded dh-linktree 0.2 (minor doc update), sql-ledger 2.8.36 (new upstream version), logidee-tools 1.2.12 (minor fixes) and publican 2.8-2 (to fix release critical bug #660795). Debian Consultants The Debian Project Leader is working on federating Debian Companies. As the owner of Freexian SARL, I was highly interested in it since Freexian contributes to Debian, offers support for Debian and has a strategic interest in Debian . There s only one problem, you need to have at least 2 Debian developers on staff but I have no employees (it s me only). I tried to argue that I have already worked with multiple Debian developers (as contractors) when projects were too big for me alone (or when I did not have enough time). Alas this argument was not accepted. Instead, and since our fearless leader is never afraid to propose compromises, he suggested me (and MJ Ray who argued something similar than me) to try to bring life to the Debian Consultants list which (in his mind) would be more appropriate for one-man companies like mine. I accepted to help animate the list, and on his side, he s going to promote both the Debian Companies and the Debian Consultants lists. In any case, the list has seen some traffic lately and you re encouraged to join if you re a freelancer offering services around Debian. The most promising thing is that James Bromberger offered to implement a real database of consultants instead of the current static page. Book update We made quite some progress this month. There s only one chapter left to translate. I thus decided to start with proofreading. I made a call for volunteers and I submitted one (different) chapter to 5 proofreaders. The liberation campaign made a nice leap forwards thanks to good coverage on barrapunto.com. We have reached 80% while we were only at 72% at the start of the month (thanks to the 113 new supporters!). There s thus less than 5000 EUR to raise before the book gets published under a free license. Looking at the progression in the past months, this is unlikely to be completed on time for the release of the book in April. It would be nice though so please share the news around you. Speaking of the book s release, I m slowly preparing it. Translating docbook files is not enough, I must be able to generate HTML, ePub and PDF versions of the book. I m using Publican for most formats, but for the PDF version Publican is moving away of fop and the replacement (webkit-based) is far from being satisfactory to generate a book ready for print. So I plan to use dblatex and get Publican to support dblatex as a backend. I have hired Beno t Guillon, the upstream author of dblatex, to fix some annoying bugs and to improve it to suit my needs for the book (some results are already in the upstream CVS repository). I m also working with a professional book designer to get a nice design. I have also started to look for a Python Django developer to build the website that I will use to commercialize the book. The website will have a larger goal than just this though ( helping to fund free software developers ) but in free software it s always good to start with your own case. :-) Hopefully everything will be ready in April. I m working hard to meet that deadline (you might have noticed that my blog has been relatively quiet in the last month ). Thanks See you next month for a new summary of my activities.

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7 February 2012

Rapha&#235;l Hertzog: Dpkg with multiarch support available in Debian experimental

As I announced on debian-devel, Guillem Jover uploaded a snapshot of dpkg s multiarch branch to experimental (version 1.16.2~wipmultiarch). Beware: There will
likely be some small interface changes between this version and the version that will be released later in unstable (possibly in the output of dpkg --get-selections, dpkg --list, maybe other commands). multiarch allows you to install packages from different architectures on the same machine. This can be useful if your computer can run programs from 2 architectures (eg. x86 CPU supporting i386 and amd64), or if you often need to cross-compile software and thus need the libraries of your target architecture. Test dpkg with multiarch support If you want to test multiarch support in dpkg, install the package from experimental (apt-get install dpkg/experimental assuming you have experimental in your sources.list). Then you can add a supplementary architecture to your system by doing sudo dpkg --add-architecture <arch> (e.g. i386 if you are on amd64, and vice-versa). APT will automatically pick up the new architecture and start downloading the Packages file for the new architecture (it uses dpkg --print-foreign-architectures to know about them). From there on you can install packages from the foreign architectures with apt-get install foo:<arch> . Many packages will not be installable because some of their dependencies have not yet been updated to work with in a multiarch world (libraries must be installed in a multiarch-compliant path so as to be co-installable, and then marked Multi-Arch: same ). Other dependencies might need to be marked Multi-Arch: foreign . See wiki.debian.org/Multiarch/Implementation for more HOWTO-like explanations. Now is a good time to see if you can install the foreign packages that you could need in such a setup and to help to convert the required libraries. You can also read Cyril Brulebois article which quickly shows how to hunt for the problematic packages which have not been converted to multiarch (in his sample, ucf is not ready. Since it s an Architecture: all package which can run on any architecture, it means that it s lacking a Multi-Arch: foreign field). Report bugs If you discover any bug in dpkg s multiarch implementation, please report it to the Bug Tracking System (against dpkg with the version 1.16.2~wipmultiarch ). If you notice important libraries or packages which are not yet multiarch ready, please open wishlist bug reports requesting the conversion and point the maintainers towards the wiki page linked above. Even better, prepare patches and submit those with your bug reports. Again, you can follow the lead of Cyril Brulebois who filed 6 bugs! Review the multiarch implementation If you re a C programmer and have some good knowledge of dpkg (or are willing to learn more of it), we would certainly benefit from more eyes reviewing the multiarch branch. If you want to discuss some design issues of the multiarch implementation in dpkg (or have questions related to your review), please get in touch via debian-dpkg@lists.debian.org. The latest version of the branch is pu/multiarch/master in Guillem s personal repository. I have my own version of the branch (pu/multiarch/full) which is usually a snapshot of Guillem s branch with my own submitted fixes.
$ git clone git://git.debian.org/dpkg/dpkg.git
$ cd dpkg
$ git remote add guillem git://git.hadrons.org/git/debian/dpkg/dpkg.git
$ git remote add buxy git://git.debian.org/~hertzog/dpkg.git
$ git fetch guillem && git fetch buxy
If you followed the instructions above, the relevant branches are thus guillem/pu/multiarch/master and buxy/pu/multiarch/full. Both branches are regularly rebased on top of master where Guillem merges progressively the commits from the multi-arch branch as his review progresses. Thank you in advance for your help bringing multiarch in shape for Debian Wheezy,

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1 February 2012

Rapha&#235;l Hertzog: My Debian Activities in January 2012

This is my monthly summary of my Debian related activities. If you re among the people who made a donation to support my work (213.68 , thanks everybody!), then you can learn how I spent your money. Otherwise it s just an interesting status update on my various projects. Dpkg The biggest change I made is a small patch that brings to an end years and years of recurring discussions about the build-arch and build-indep targets of debian/rules (see #229357). Last year the technical committee took this issue in its hands (see #629385) but it failed to take any resolution. Fortunately thanks to this we got some concrete numbers on the colateral damages inflicted on the archive for each possible approach. In the end, Guillem and I managed to agree on the way forward. The remaining of what I did as dpkg maintainer has not much to do with coding. I reviewed the work of Gianluca Ciccarelli on dpkg-maintscript-helper who is trying to provide helper functions to handle migration between directories and symlinks. I also reviewed a 2000-lines patch from Patrick Schoenfeld who s trying to provide a perl API to parse dpkg log files and extract meaningful data out of them. I updated the dpkg-architecture manual page to document the Makefile snippet /usr/share/dpkg/architecture.mk and to drop information that s no longer releveant nowadays. I reviewed a huge patch prepared by Russ Alberry to update the Debian policy and document the usage of symbols files for libraries. As the author of dpkg-gensymbols, I was keen to see it properly documented at the policy level. I brought up for discussion a detail that was annoying me for quite some time: some copyright notices were embedded in translatable strings and updating them resulted in useless work for translators. In the end we decided to drop those notices and to keep them only at the source level. I updated my multiarch branch on top of Guillem s branch several times, all the fixes that were in my branch have been integrated (often in a modified form). Unfortunately even if the code works quite well, Guillem doesn t want to release anything to Debian until he has finished to review everything and many people are annoyed by the unreasonable delay that it imposes. Cyril Brulebois tried to release a snapshot of the current multiarch branch to experimental but Guillem has been prompt to revert this upload. I m somewhat at a loss in this situation. I offered my help to Guillem multiple times but he keeps doing his work in private, he doesn t share many details of his review except some comments in commit logs or when it affects the public interface. I complained once more of this sad situation. Debian Package Maintenance Hub That s the codename I use for a new infrastructure that I would like to develop to replace the Package Tracking System and the DDPO and several other services. I started to draft a Debian Enhancement Proposal (DEP), see DEP-2, and requested some comments within the QA team. For now, it looks like that nobody had major objections on the driving idea behind this project. Those who commented were rather enthusiastic. I will continue to improve this DEP within the QA team and at some point I will bring the discussion to a larger audience like debian-devel@lists.debian.org. Package Tracking System Even if I started to design its replacement, the PTS will still be used for quite some time so I implemented two new features that I deemed important: displaying a TODO notice when there is (at least) one open bug related to a release goal, displaying a notice when the package is involved in an ongoing or upcoming transition. Misc packaging tasks I created and uploaded the dh-linktree package which is a debhelper addon to create symlink trees (useful to replace embedded copies of PHP/JavaScript libraries by symlinks to packaged copies of those files). I packaged quilt 0.50. I helped the upstream authors to merge a Debian patch that had been forwarded by Martin Quinson (a quilt s co-maintainer). I packaged a security release of WordPress (3.3.1) and a new upstream release of feed2omb and gnome-shell-timer. I prepared a new Debian release of python-django with a patch cherry-picked from the upstream SVN repository to fix the RC bug #655666. Book update We re again making decent progress in the translation of the Debian Administrator s Handbook, about 12 chapters are already translated. The liberation campaign is also (slowly) going forward. We re at 72% now (thanks to 63 new supporters!) while we were only at 67% at the start of January. Thanks See you next month for a new summary of my activities.

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