=head1 NAME

SuikaWiki::DB::Util --- SuikaWiki WikiDatabase: WikiDatabase modules common utilities

=head1 DESCRIPTION

This module provides some functions expected to be useful for most WikiDatabase
implememtation modules.

This module is part of SuikaWiki.

=cut

package SuikaWiki::DB::Util;
use strict;
our $VERSION=do{my @r=(q$Revision: 1.2 $=~/\d+/g);sprintf "%d."."%02d" x $#r,@r};
our $Err;

=head1 FUNCTIONS

=over 4

=item $err = SuikaWiki::DB::Util->error_handler ()

Returns error handler object (Message::Util::Error instance).

=cut

sub error_handler ($;%) {
  return $Err if $Err;
  my (undef, %opt) = @_;
  
  require Message::Util::Error;
  $Err = Message::Util::Error->new ({
    ## Error level:
    ## - stop:  cannot continue the operation (but other operations 
    ##          might be able to be performed)
    ## - fatal: cannot continue any operation anymore
    ## - warn:  simple warning or harmless error
    ## - debug: debug message
    DB_OPEN => {
      level => 'fatal',
      description => q(Can't open database),
    },
    DB_UNSUPPORTED_FORMAT => {
      level => 'stop',
      description => q(Unsupported format of database),
    },
    DB_SAVE => {
      level => 'stop',
      description => q(Can't save database.  Data might be lost),
    },
    DB_CLOSE => {
      level => 'warn',
      description => q(Can't close database),
    },
    LOCK_START => {
      level => 'fatal',
      description => q(Can't lock),
    },
    LOCK_END => {
      level => 'warn',
      description => q(Can't unlock),
    },
    KEY_INVALID_NAME => {
      level => 'stop',
      description => q(Invalid key name),
    },
    KEY_INVALID_NS_NAME => {
      level => 'stop',
      description => q(Invalid key namespace),
    },                                
    KEY_SAVE => {
      level => 'stop',
      description => q(Can't save to database),
    },
    UNKNOWN => {
      level => 'fatal',
      description => 'Unknown error',
    },
    -error_handler => $opt{-error_handler},
  });
  $Err;
}

=item $locker = SuikaWiki::DB::Util->new_lock ($options)

Returns new locker object (SuikaWiki::DB::Util::Lock instance).

=cut

sub new_lock ($$) {
  require SuikaWiki::DB::Util::Lock;
  return SuikaWiki::DB::Util::Lock->new (%{$_[1]});
}

=back

=cut

=head1 SEE ALSO

C<SuikaWiki::DB>

=head1 AUTHOR

Wakaba <w@suika.fam.cx>.

=head1 LICENSE

Copyright AUTHOR 2003.

This program is free software; you can redistribute it and/or
modify it under the same terms as Perl itself.

=cut

1; # $Date: 2003/08/06 02:54:40 $