MDV::Distribconf(3)

NAME
MDV::Distribconf - Read and write config of a distribution tree

SYNOPSIS
    use MDV::Distribconf;

    my $d = MDV::Distribconf->new("/path/to/the/distribution/root");
    $d->load()
        or die "This doesn't seem to be a distribution tree\n";

    print $d->getpath(undef, "root") ."\n";
    foreach ($d->listmedia) {
        printf "%s -> %s\n", $d->getpath($_, "hdlist"), $d->getpath($_, path);
    }

DESCRIPTION
MDV::Distribconf is a module to get or write the configuration of a Mageia distribution tree. This configuration is stored in a file called media.cfg, aimed at replacing the old-style hdlists file.

The format of the hdlists file is limited and doesn't allow to add new values without breaking compatibility, while media.cfg is designed for extensibility. To keep compatibility with old tools, this module is able to generate an hdlists file based on media.cfg.

This module is able to manage both configuration of old-style trees (Mandrake/base/ for OS versions 10.0 and older) and of new-style ones (media/media_info/ for 10.1 and newer).

media.cfg
The media.cfg is structured like a classical .ini file. All parameters are optional; this means that a readable empty file is ok, if this is what you want :)

media.cfg contains sections, each section corresponding to a media, except the "[media_info]" section wich is used to store global info. The section name is the (relative) path where the rpms are located. It is sufficient to uniquely identify a media.

Some values have specific signification:

media specific values:
    hdlist
        The path or basename of the hdlist. By default, this is "hdlist_mediapath.cz", with slashes and spaces being replaced by '_'.

    synthesis
        The path or basename of the synthesis. By default, this is the hdlist name prefixed by "synthesis".

    pubkey
        The path or basename of the gpg public key file. By default, this is the media name prefixed by "pubkey_".

    name
        A human-readable name for the media. By default this is the media path (that is, the section name), where slashes have been replaced by underscores.

    info
        The xml file containing rpm informations.

    changelog
        The xml file containing rpm changelogs.

    files
        The xml file containing rpm files list.

global specific values:
    version
        OS version.

    branch
        OS branch (cauldron, etc.)

    arch
        Media target architecture.

    root
        The root path of the distribution tree. This value is not set in media.cfg, can't be owerwritten, and is only used internally.

    mediadir
        The default path relative to the 'root' path where media are located. MDV::Distribconf is supposed to configure this automatically to "Mandrake" or to "media", depending on the OS version.

    infodir
        The default path relative to the 'root' path where distrib metadata are located. MDV::Distribconf is supposed to configure this automatically to "Mandrake/base" or to "media/media_info", depending on the OS version.

For the paths of the hdlist and synthesis files, if only a basename is provided, the path is assumed to be relative to the mediadir or infodir. (hdlist and synthesis are created in both directories.) If it's a complete path, it's assumed to be relative to the 'root'. For example,

    hdlist.cz    -> <root>/<infodir>/hdlist.cz
    ./hdlist.cz  -> <root>/./hdlist.cz

Here's a complete example of a media.cfg file:

    # Comment
    [media_info]
    # some tools can use those values
    version=2006.0
    branch=cauldron

    [core]
    hdlist=hdlist_core.cz
    name=Core

    [../SRPMS/core]
    hdlist=hdlist_core.src.cz
    name=Core Sources
    noauto=1

    [contrib]
    hdlist=hdlist_contrib.cz
    name=Contrib

    [../SRPMS/contrib]
    hdlist=hdlist_contrib.src.cz
    name=Contrib Sources
    noauto=1

METHODS

  MDV::Distribconf->new($root)
Returns a new MDV::Distribconf object, $root being the top level directory of the tree.

  $distrib->load()
Finds and loads the configuration of the distrib: locate the path where information is found; if available loads media.cfg, if available loads hdlists.

Returns 1 on success, 0 error (that is, if no directory containing media information is found, or if no media.cfg, neither hdlists files are found).

See also loadtree, parse_hdlists and parse_mediacfg.

  $distrib->loadtree()
Tries to find a valid media information directory, and set infodir and mediadir. Returns 1 on success, 0 if no media information directory was found.

  check_mediacfg_version($wanted_version)
Check that the current distrib uses this version or lesser, which means it is supported.

  $distrib->settree($spec)
Virtual set the internal structure of the distrib.

$spec can be 'mandrake' or 'mandriva' to automatically load a know structure (old and new fascion, or a hashref:

  mediadir => 'media',
  infodir => 'media/media_info',

  $distrib->parse_hdlists($hdlists)
Reads the hdlists file whose path is given by the parameter $hdlist, or, if no parameter is specified, the hdlists file found in the media information directory of the distribution. Returns 1 on success, 0 if no hdlists can be found or parsed.

  $distrib->parse_version($fversion)
Reads the VERSION file whose path is given by the parameter $fversion, or, if no parameter is specified, the VERSION file found in the media information directory of the distribution. Returns 1 on success, 0 if no VERSION can be found or parsed.

  $distrib->parse_mediacfg($mediacfg)
Reads the media.cfg file whose path is given by the parameter $mediacfg, or, if no parameter is specified, the media.cfg file found in the media information directory of the distribution. Returns 1 on success, 0 if no media.cfg can be found or parsed.

  $distrib->listmedia()
Returns an array of existing media in the configuration

  $distrib->mediaexists($media)
Return true if $media exists

  $distrib->getvalue($media, $var)
Returns the $var value for $media, or "undef" if the value is not set.

If $var is "name", "hdlist" or "synthesis", and if the value is not explicitly defined, the return value is expanded from $media.

If $media is "media_info" or "undef", you'll get the global value.

This function doesn't cares about path, see getpath for that.

  $distrib->getpath($media, $var)
Gives relative path of $var from the root of the distrib. This function is useful to know where files are actually located. It takes care of location of media, location of index files, and paths set in the configuration.

  $distrib->getmediapath($media, $var)
This function does the same than getpath except it return the path proper to the media for files having doble location (index for example).

  $distrib->getfullpath($media, $var)
Does the same thing than getpath(), but the return value will be prefixed by the 'root' path. This is a shortcut for:

    $distrib->getpath(undef, 'root') . '/' . $distrib->getpath($media, $var).

  $distrib->getfullmediapath($media, $var)
This function does the same than getpath except it return the path proper to the media for files having doble location (index for example).

  $distrib->getdpath($media, $var)
Does the same thing than getpath(), but the return always return the best for file having twice location (index).

You may want to use this function to ensure you allways the good value.

  $distrib->getfulldpath($media, $var)
Does the same thing than getfullpath(), but the return always return the best for file having twice location (index).

You may want to use this function to ensure you allways the good value.

SEE ALSO
gendistrib(1) MDV::Distribconf::Build MDV::Distribconf::MediaCFG MDV::Distribconf::Checks

AUTHOR
The code has been written by Olivier Thauvin <nanardon@mandriva.org> and is currently maintained by Rafael Garcia-Suarez <rgarciasuarez@mandriva.com>. Thanks to Sylvie Terjan <erinmargault@mandriva.org> for the spell checking.

LICENSE AND COPYRIGHT
(c) 2005, 2006, 2007 Olivier Thauvin (c) 2005, 2006, 2007 Mandriva

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.