dahdi_genconf: configuration handling cleanup.

* Parsing genconf_parameters is now in Dahdi::Config::Params
  All hard-coded defaults are there too (in the item() method).
* Dahdi::Config::Genconf is gone (merged into Dahdi::Config::Gen)
  All semantic mapping is in the constructor.
* dahdi_genconf is now lean and mean.
* Add some implementation docs into these files. 


git-svn-id: http://svn.asterisk.org/svn/dahdi/tools/trunk@6075 a0bf4364-ded3-4de4-8d8a-66a801d63aff

7 files changed, 385 insertions, 178 deletions

diff --git a/xpp/dahdi_genconf b/xpp/dahdi_genconf
index cba1963..2988343 100755
--- a/xpp/dahdi_genconf
+++ b/xpp/dahdi_genconf
@@ -14,187 +14,52 @@ BEGIN { my $dir = dirname($0); unshift(@INC, "$dir", "$dir/perl_modules"); }
 use Getopt::Std;
 use Dahdi;
 use Dahdi::Xpp;
-use Dahdi::Config::GenconfDefaults;
+use Dahdi::Config::Gen;
+use Dahdi::Config::Params;
 
 my $version = '1';	# Functionality version (integer)
 my $revision = '$Revision$';
 
 my %opts;
-my $genconf_defaults;
-
-my %default_context = (
-	FXO	=> 'from-pstn',
-	FXS	=> 'from-internal',
-	IN	=> 'astbank-input',
-	OUT	=> 'astbank-output',
-	BRI_TE	=> 'from-pstn',
-	BRI_NT	=> 'from-internal',
-	E1_TE	=> 'from-pstn',
-	T1_TE	=> 'from-pstn',
-	J1_TE	=> 'from-pstn',
-	E1_NT	=> 'from-internal',
-	T1_NT	=> 'from-internal',
-	J1_NT	=> 'from-internal',
-	);
-
-my %default_group = (
-	FXO	=> 0,
-	FXS	=> "5",
-	IN	=> '',
-	OUT	=> '',
-	BRI_TE	=> 0,
-	BRI_NT	=> 6,
-	E1_TE	=> 0,
-	T1_TE	=> 0,
-	J1_TE	=> 0,
-	E1_NT	=> 6,
-	T1_NT	=> 6,
-	J1_NT	=> 6,
-	);
-
-my $fxs_default_start = 'ks';
-
-my %default_dahdi_signalling = (
-	FXO	=> 'fxsks',
-	FXS	=> "fxo{fxs_default_start}",
-	IN	=> "fxo{fxs_default_start}",
-	OUT	=> "fxo{fxs_default_start}",
-	);
-
-my %default_chan_dahdi_signalling = (
-	FXO	=> 'fxs_ks',
-	FXS	=> "fxo_{fxs_default_start}",
-	IN	=> "fxo_{fxs_default_start}",
-	OUT	=> "fxo_{fxs_default_start}",
-	);
-
-my $lc_country = 'us';
-my $pri_termtype = 'SPAN/* TE';
-my $echo_can = 'mg2';
-
-my %global_config = (
-		'genconf_file'	=> 'HARD-CODED-DEFAULT',	# GenconfDefaults override
-		'base_exten'	=> 4000,
-		'freepbx'	=> 'no',			# Better via -F command line
-		'fxs_immediate'	=> 'no',
-		'loadzone'	=> $lc_country,
-		'defaultzone'	=> $lc_country,
-		'context'	=> \%default_context,
-		'group'		=> \%default_group,
-		'bri_hardhdlc'	=> 'no',
-		'bri_sig_style'	=> 'bri_ptmp',
-		'r2_idle_bits'	=> '1101',
-		'brint_overlap'	=> 'no',
-		'pri_connection_type'	=> 'PRI', # PRI or R2
-		'dahdi_signalling'	=> \%default_dahdi_signalling,
-		'chan_dahdi_signalling'	=> \%default_chan_dahdi_signalling,
-	);
-
-my %dahdi_default_vars = (
-		GENCONF_FILE		=> \$global_config{'genconf_file'},
-		base_exten		=> \$global_config{'base_exten'},
-		freepbx			=> \$global_config{'freepbx'},
-		fxs_immediate		=> \$global_config{'fxs_immediate'},
-		fxs_default_start	=> \$fxs_default_start,
-		lc_country		=> [
-						\$global_config{'loadzone'},
-						\$global_config{'defaultzone'},
-					],
-		context_lines		=> \$default_context{FXO},
-		context_phones		=> \$default_context{FXS},
-		context_input		=> \$default_context{IN},
-		context_output		=> \$default_context{OUT},
-		group_phones		=> [
-						\$default_group{FXS},
-						\$default_group{IN},
-						\$default_group{OUT},
-					],
-		group_lines		=> \$default_group{FXO},
-		bri_sig_style		=> \$global_config{'bri_sig_style'},
-		brint_overlap		=> \$global_config{'brint_overlap'},
-		pri_termtype		=> \$pri_termtype,
-		pri_connection_type	=> \$global_config{'pri_connection_type'},
-		r2_idle_bits		=> \$global_config{'r2_idle_bits'},
-		echo_can		=> \$echo_can,
-		bri_hardhdlc		=> \$global_config{'bri_hardhdlc'},
-		);
-
-sub map_dahdi_defaults {
-	my %defaults = @_;
-	foreach my $name (keys %defaults) {
-		my $val = $defaults{$name};
-		my $ref = $dahdi_default_vars{$name};
-		my $type = ref $ref;
-		my @vars = ();
-		# Some broken shells (msh) export even variables
-		# That where not defined. Work around that.
-		next unless defined $val && $val ne '';
-		if($type eq 'SCALAR') {
-			@vars = ($ref);
-		} elsif($type eq 'ARRAY') {
-			@vars = @$ref;
-		} else {
-			die "$0: Don't know how to map '$name' (type=$type)\n";
-		}
-		foreach my $v (@vars) {
-			$$v = $val;
-			#printf STDERR "%-20s %s\n", $v, $val;
-		}
-	}
-}
-
-my @spans = Dahdi::spans();
 
 sub set_defaults {
-	# Source default files
 	my $default_file = $ENV{GENCONF_PARAMETERS} || "/etc/dahdi/genconf_parameters";
-	$genconf_defaults = Dahdi::Config::GenconfDefaults->new($default_file);
+	my $params = Dahdi::Config::Params->new($default_file);
+	#$params->dump;
 	if($opts{v}) {
-		print "Default parameters from ", $genconf_defaults->{GENCONF_FILE}, "\n";
+		print "Default parameters from ", $params->{GENCONF_FILE}, "\n";
 	}
-	map_dahdi_defaults(%$genconf_defaults);
+	my $gconfig = Dahdi::Config::Gen->new($params);
+	#$gconfig->dump;
+	return $gconfig;
+}
+
+sub spans_prep($@) {
+	my $gconfig = shift || die;
+	my @spans = @_;
 	foreach my $span (@spans) {
 		if($span->is_pri) {
-			$span->pri_set_fromconfig($genconf_defaults);
+			$span->pri_set_fromconfig($gconfig);
 		}
 	}
-	# Fixups
-	foreach my $val (values %default_dahdi_signalling, values %default_chan_dahdi_signalling) {
-		$val =~ s/{fxs_default_start}/$fxs_default_start/g;
-	}
-	#$genconf_defaults->dump;
 }
 
-sub parse_args {
-	my @default_generators;
+sub generator_list($) {
+	my $gconfig = shift || die;
+	my @genlist;
 
 	if (@ARGV) {
 		for my $gen (@ARGV) {
-			push @default_generators, $gen;
+			push @genlist, $gen;
 		}
 	} else {
 		# No files given. Use the defaults.
-		@default_generators = ('system', 'chandahdi');
-		if($global_config{'pri_connection_type'} eq 'R2') {
-			push @default_generators, 'unicall';
+		@genlist = ('system', 'chandahdi');
+		if($gconfig->{'pri_connection_type'} eq 'R2') {
+			push @genlist, 'unicall';
 		}
 	}
-	return @default_generators;
-}
-
-sub run_generator($$) {
-	my ($name, $genopts) = @_;
-
-	if(defined $opts{'v'}) {
-		$genopts->{'verbose'} = $opts{v};
-	}
-	my $module = "Dahdi::Config::Gen::$name";
-	eval "use $module";
-	if($@) {
-		die "Failed to load configuration generator for '$name'\n";
-	}
-	my $cfg = new $module(\%global_config, $genopts);
-	$cfg->generate(@spans);
+	return @genlist;
 }
 
 sub parse_genopts($) {
@@ -210,16 +75,21 @@ sub parse_genopts($) {
 	return %genopts;
 }
 
-sub generate_files(@) {
-	my @default_generators = @_;
+sub generate_files($@) {
+	my $gconfig = shift || die;
+	my @spans = @_;
+	my @generators = generator_list($gconfig);
 
-	for my $gen (@default_generators) {
+	for my $gen (@generators) {
 		my ($name, $optstr) = split(/=/, $gen, 2);
 		die "Illegal name '$name'\n" unless $name =~ /^\w+$/;
 		$name =~ s/(.)(.*)/\u$1\L$2/;
 		my %genopts = parse_genopts($optstr);
 		$genopts{'freepbx'} = 'yes' if $opts{'F'};
-		run_generator($name, \%genopts);
+		if(defined $opts{'v'}) {
+			$genopts{'verbose'} = $opts{v};
+		}
+		$gconfig->run_generator($name, \%genopts, @spans);
 	}
 }
 
@@ -232,9 +102,10 @@ if($opts{'V'}) {
 	exit 0;
 }
 
-my @default_generators = parse_args;
-set_defaults;
-generate_files @default_generators;
+my $gconfig = set_defaults;
+my @spans = Dahdi::spans();
+spans_prep($gconfig, @spans);
+generate_files($gconfig, @spans);
 
 __END__
 
@@ -279,7 +150,7 @@ a comma separated list of options to the generator name. E.g:
 
  dahdi_genconf system chandahdi=verbose unicall
 
-Global options:
+=head1 Global options:
 
 =over 4
 
@@ -298,3 +169,28 @@ Currently, chandahdi is affected.
 
 
 =back
+
+=head1 Implementation notes:
+
+=over 4
+
+=item *
+
+F<genconf_parameters> parsing is done via C<Dahdi::Config::Params>.
+An object representing the parsed data is instanciated by:
+C<Dahdi::Config::Params-E<gt>new()>.
+The C<item()> method of this object contains all the hard coded
+defaults of the configuration directives.
+
+=item *
+
+A configuration object is instanciated by C<Dahdi::Config::Gen-E<gt>new($params)>.
+The mapping of configuration directives into semantic configuration is
+done in the constructor.
+
+=item *
+
+A single generator is run via the the C<run_generator()> method of the
+configuration object.
+
+=back
diff --git a/xpp/perl_modules/Dahdi/Config/Gen.pm b/xpp/perl_modules/Dahdi/Config/Gen.pm
index 556e193..b68fa28 100644
--- a/xpp/perl_modules/Dahdi/Config/Gen.pm
+++ b/xpp/perl_modules/Dahdi/Config/Gen.pm
@@ -1,4 +1,46 @@
 package Dahdi::Config::Gen;
+#
+# Written by Oron Peled <oron@actcom.co.il>
+# Copyright (C) 2009, Xorcom
+# This program is free software; you can redistribute and/or
+# modify it under the same terms as Perl itself.
+#
+# $Id$
+#
+
+=head1 NAME
+
+Dahdi::Config::Gen -- Wrapper class for configuration generators.
+
+=head1 SYNOPSIS
+
+ use Dahdi::Config::Gen qw(is_true);
+ my $params = Dahdi::Config::Params->new('the-config-file');
+ my $gconfig = Dahdi::Config::Gen->new($params);
+ my $num = $gconfig->{'base_exten'};
+ my $overlap = is_true($gconfig->{'brint_overlap'});
+ $gconfig->dump;	# For debugging
+ $gconfig->run_generator('system', {}, @spans);
+
+=head1 DESCRIPTION
+
+The constructor must be given an C<Dahdi::Config::Params> object.
+The returned object contains all data required for generation in the
+form of a hash.
+
+The constructor maps the C<item()>s from the parameter object into semantic
+configuration keys.  E.g: the C<lc_country> item is mapped to C<loadzone> and
+C<defaultzone> keys.
+
+The actual generation is done by delegation to one of the generators.
+This is done via the C<run_generator()> method which receive the
+generator name, a generator specific options hash and a list of
+span objects (from C<Dahdi::Span>) for which to generate configuration.
+
+This module contains few helper functions. E.g: C<is_true()>, C<bchan_range()>.
+
+=cut
+
 require Exporter;
 @ISA = qw(Exporter);
 
@@ -6,21 +48,15 @@ require Exporter;
 
 use strict;
 
+# Parse values as true/false 
 sub is_true($) {
 	my $val = shift;
 	return undef unless defined $val;
 	return $val =~ /^(1|y|yes)$/i;
 }
 
-sub show_gconfig($) {
-	my $gconfig = shift || die;
-
-	print "Global configuration:\n";
-	foreach my $key (sort keys %{$gconfig}) {
-		printf "  %-20s %s\n", $key, $gconfig->{$key};
-	}
-}
-
+# Generate channel range strings from span objects
+# E.g: "63-77,79-93"
 sub bchan_range($) {
 	my $span = shift || die;
 	my $first_chan = ($span->chans())[0];
@@ -46,4 +82,131 @@ sub bchan_range($) {
 	return join(',', @range);
 }
 
+sub new($) {
+	my $pack = shift || die "$0: Missing package argument";
+	my $p = shift || die "$0: Missing parameters argument";
+
+	# Set defaults
+	my $fxs_default_start = $p->item('fxs_default_start');
+
+	my %default_context = (
+		FXO	=> $p->item('context_lines'),
+		FXS	=> $p->item('context_phones'),
+		IN	=> $p->item('context_input'),
+		OUT	=> $p->item('context_output'),
+		BRI_TE	=> $p->item('context_lines'),
+		BRI_NT	=> $p->item('context_phones'),
+		E1_TE	=> $p->item('context_lines'),
+		T1_TE	=> $p->item('context_lines'),
+		J1_TE	=> $p->item('context_lines'),
+		E1_NT	=> $p->item('context_phones'),
+		T1_NT	=> $p->item('context_phones'),
+		J1_NT	=> $p->item('context_phones'),
+		);
+	my %default_group = (
+		FXO	=> $p->item('group_lines'),
+		FXS	=> $p->item('group_phones'),
+		IN	=> '',
+		OUT	=> '',
+		BRI_TE	=> 0,
+		BRI_NT	=> 6,
+		E1_TE	=> 0,
+		T1_TE	=> 0,
+		J1_TE	=> 0,
+		E1_NT	=> 6,
+		T1_NT	=> 6,
+		J1_NT	=> 6,
+		);
+	my %default_dahdi_signalling = (
+		FXO	=> 'fxsks',
+		FXS	=> "fxo$fxs_default_start",
+		IN	=> "fxo$fxs_default_start",
+		OUT	=> "fxo$fxs_default_start",
+		);
+	my %default_chan_dahdi_signalling = (
+		FXO	=> 'fxs_ks',
+		FXS	=> "fxo_$fxs_default_start",
+		IN	=> "fxo_$fxs_default_start",
+		OUT	=> "fxo_$fxs_default_start",
+		);
+
+	# First complex mapping
+	my $gconfig = {
+			PARAMETERS	=> $p,
+			'loadzone'	=> $p->item('lc_country'),
+			'defaultzone'	=> $p->item('lc_country'),
+			'context'	=> \%default_context,
+			'group'		=> \%default_group,
+			'dahdi_signalling'	=> \%default_dahdi_signalling,
+			'chan_dahdi_signalling'	=> \%default_chan_dahdi_signalling,
+		};
+	# Now add trivial mappings
+	my @trivial = qw(
+		base_exten
+		freepbx
+		fxs_immediate
+		bri_hardhdlc
+		bri_sig_style
+		r2_idle_bits
+		echo_can
+		brint_overlap
+		pri_termtype
+		pri_connection_type
+		);
+	foreach my $k (@trivial) {
+		$gconfig->{$k} = $p->item($k);
+	}
+	bless $gconfig,$pack;
+
+	return $gconfig;
+}
+
+sub run_generator($$@) {
+	my $gconfig = shift || die;
+	my $name = shift || die "$0: Missing generator name argument";
+	my $genopts = shift || die "$0: Missing genopts argument";
+	ref($genopts) eq 'HASH' or die "$0: Bad genopts argument";
+	my @spans = @_;
+
+	my $module = "Dahdi::Config::Gen::$name";
+	#print STDERR "DEBUG: $module\n";
+	eval "use $module";
+	if($@) {
+		die "Failed to load configuration generator for '$name'\n";
+	}
+	my $cfg = $module->new($gconfig, $genopts);
+	$cfg->generate(@spans);
+}
+
+sub dump($) {
+	my $self = shift || die;
+	printf STDERR "%s dump:\n", ref $self;
+	my $width = 30;
+	foreach my $k (sort keys %$self) {
+		my $val = $self->{$k};
+		my $ref = ref $val;
+		#print STDERR "DEBUG: '$k', '$ref', '$val'\n";
+		if($ref eq '') {
+			printf STDERR "%-${width}s %s\n", $k, $val;
+		} elsif($ref eq 'SCALAR') {
+			printf STDERR "%-${width}s %s\n", $k, ${$val};
+		} elsif($ref eq 'ARRAY') {
+			#printf STDERR "%s:\n", $k;
+			my $i = 0;
+			foreach my $v (@{$val}) {
+				printf STDERR "%-${width}s %s\n", "$k\->[$i]", $v;
+				$i++;
+			}
+		} elsif($ref eq 'HASH') {
+			#printf STDERR "%s:\n", $k;
+			foreach my $k1 (keys %{$val}) {
+				printf STDERR "%-${width}s %s\n", "$k\->\{$k1\}", ${$val}{$k1};
+			}
+		} else {
+			printf STDERR "%-${width}s (-> %s)\n", $k, $ref;
+		}
+	}
+}
+
+
 1;
diff --git a/xpp/perl_modules/Dahdi/Config/Gen/Chandahdi.pm b/xpp/perl_modules/Dahdi/Config/Gen/Chandahdi.pm
index f48455d..1f39a7a 100644
--- a/xpp/perl_modules/Dahdi/Config/Gen/Chandahdi.pm
+++ b/xpp/perl_modules/Dahdi/Config/Gen/Chandahdi.pm
@@ -131,7 +131,7 @@ sub generate($) {
 	my $file = $self->{FILE};
 	my $gconfig = $self->{GCONFIG};
 	my $genopts = $self->{GENOPTS};
-	#Dahdi::Config::Gen::show_gconfig($gconfig);
+	#$gconfig->dump;
 	my @spans = @_;
 	warn "Empty configuration -- no spans\n" unless @spans;
 	rename "$file", "$file.bak"
diff --git a/xpp/perl_modules/Dahdi/Config/Gen/System.pm b/xpp/perl_modules/Dahdi/Config/Gen/System.pm
index da60ec4..f805b65 100644
--- a/xpp/perl_modules/Dahdi/Config/Gen/System.pm
+++ b/xpp/perl_modules/Dahdi/Config/Gen/System.pm
@@ -107,7 +107,7 @@ sub generate($$$) {
 	rename "$file", "$file.bak"
 		or $! == 2	# ENOENT (No dependency on Errno.pm)
 		or die "Failed to backup old config: $!\n";
-	#Dahdi::Config::Gen::show_gconfig($gconfig);
+	#$gconfig->dump;
 	print "Generating $file\n" if $genopts->{verbose};
 	open(F, ">$file") || die "$0: Failed to open $file: $!\n";
 	my $old = select F;
diff --git a/xpp/perl_modules/Dahdi/Config/Gen/Unicall.pm b/xpp/perl_modules/Dahdi/Config/Gen/Unicall.pm
index 526b62b..1a796f4 100644
--- a/xpp/perl_modules/Dahdi/Config/Gen/Unicall.pm
+++ b/xpp/perl_modules/Dahdi/Config/Gen/Unicall.pm
@@ -22,7 +22,7 @@ sub generate($) {
 	my $file = $self->{FILE};
 	my $gconfig = $self->{GCONFIG};
 	my $genopts = $self->{GENOPTS};
-	#Dahdi::Config::Gen::show_gconfig($gconfig);
+	#$gconfig->dump;
 	my @spans = @_;
 	warn "Empty configuration -- no spans\n" unless @spans;
 	die "Only for R2" unless $gconfig->{'pri_connection_type'} eq 'R2';
diff --git a/xpp/perl_modules/Dahdi/Config/Gen/Users.pm b/xpp/perl_modules/Dahdi/Config/Gen/Users.pm
index 36c2e65..e9d8ab9 100644
--- a/xpp/perl_modules/Dahdi/Config/Gen/Users.pm
+++ b/xpp/perl_modules/Dahdi/Config/Gen/Users.pm
@@ -73,7 +73,7 @@ sub generate($) {
 	my $file = $self->{FILE};
 	my $gconfig = $self->{GCONFIG};
 	my $genopts = $self->{GENOPTS};
-	#Dahdi::Config::Gen::show_gconfig($gconfig);
+	#$gconfig->dump;
 	my @spans = @_;
 	warn "Empty configuration -- no spans\n" unless @spans;
 	rename "$file", "$file.bak"
diff --git a/xpp/perl_modules/Dahdi/Config/Params.pm b/xpp/perl_modules/Dahdi/Config/Params.pm
new file mode 100644
index 0000000..b6d9cdc
--- /dev/null
+++ b/xpp/perl_modules/Dahdi/Config/Params.pm
@@ -0,0 +1,148 @@
+package Dahdi::Config::Params;
+#
+# Written by Oron Peled <oron@actcom.co.il>
+# Copyright (C) 2009, Xorcom
+# This program is free software; you can redistribute and/or
+# modify it under the same terms as Perl itself.
+#
+# $Id$
+#
+use strict;
+
+=head1 NAME
+
+Dahdi::Config::Params -- Object oriented representation of F<genconf_parameters> file.
+
+=head1 SYNOPSIS
+
+ use Dahdi::Config::Params;
+ my $params = Dahdi::Config::Params->new('the-config-file');
+ print $params->item{'some-key'};
+ $params->dump;	# For debugging
+
+=head1 DESCRIPTION
+
+The constructor must be given a configuration file name:
+
+=over 4
+
+=item * Missing file is B<not> an error.
+
+=item * Other opening errors cause a C<die> to be thrown.
+
+=item * The file name is saved as the value of C<GENCONF_FILE> key.
+
+=back
+
+The access to config keys should only be done via the C<item()> method:
+
+=over 4
+
+=item * It contains all hard-coded defaults.
+
+=item * All these values are overriden by directives in the config file.
+
+=back
+
+=cut
+
+sub new($$) {
+	my $pack = shift || die;
+	my $cfg_file = shift || die;
+	my $self = {
+			GENCONF_FILE	=> $cfg_file,
+		};
+	bless $self, $pack;
+	if(!open(F, $cfg_file)) {
+		if(defined($!{ENOENT})) {
+			#print STDERR "No $cfg_file. Assume empty config\n";
+			return $self; # Empty configuration
+		}
+		die "$pack: Failed to open '$cfg_file': $!\n";
+	}
+	#print STDERR "$pack: $cfg_file\n";
+	my $array_key;
+	while(<F>) {
+		my ($key, $val);
+		chomp;
+		s/#.*$//;
+		s/\s+$//;	# trim tail whitespace
+		next unless /\S/;
+		if(defined $array_key && /^\s+/) {
+			s/^\s+//;	# trim beginning whitespace
+			push(@{$self->{$array_key}}, $_);
+			next; 
+		}
+		undef $array_key;
+		($key, $val) = split(/\s+/, $_, 2);
+		$key = lc($key);
+		if(! defined $val) {
+			$array_key = $key;
+			next;
+		}
+		die "$cfg_file:$.: Duplicate key '$key'\n", if exists $self->{$key};
+		$self->{$key} = $val;
+	}
+	close F;
+	return $self;
+}
+
+sub item($$) {
+	my $self = shift || die;
+	my $key = shift || die;
+	my %defaults = (
+			base_exten		=> '4000',
+			freepbx			=> 'no',	# Better via -F command line
+			fxs_immediate		=> 'no',
+			fxs_default_start	=> 'ks',
+			lc_country		=> 'us',
+			context_lines		=> 'from-pstn',
+			context_phones		=> 'from-internal',
+			context_input		=> 'astbank-input',
+			context_output		=> 'astbank-output',
+			group_phones		=> '5',
+			group_lines		=> '0',
+			brint_overlap		=> 'no',
+			bri_sig_style		=> 'bri_ptmp',
+			echo_can		=> 'mg2',
+			bri_hardhdlc		=> 'no',
+			pri_connection_type	=> 'PRI',
+			r2_idle_bits		=> '1101',
+			'pri_termtype'		=> [ 'SPAN/* TE' ],
+		);
+
+	return (exists($self->{$key})) ? $self->{$key} :$defaults{$key};
+}
+
+sub dump($) {
+	my $self = shift || die;
+	printf STDERR "%s dump:\n", ref $self;
+	my $width = 30;
+	foreach my $k (sort keys %$self) {
+		my $val = $self->{$k};
+		my $ref = ref $val;
+		#print STDERR "DEBUG: '$k', '$ref', '$val'\n";
+		if($ref eq '') {
+			printf STDERR "%-${width}s %s\n", $k, $val;
+		} elsif($ref eq 'SCALAR') {
+			printf STDERR "%-${width}s %s\n", $k, ${$val};
+		} elsif($ref eq 'ARRAY') {
+			#printf STDERR "%s:\n", $k;
+			my $i = 0;
+			foreach my $v (@{$val}) {
+				printf STDERR "%-${width}s %s\n", "$k\->[$i]", $v;
+				$i++;
+			}
+		} elsif($ref eq 'HASH') {
+			#printf STDERR "%s:\n", $k;
+			foreach my $k1 (keys %{$val}) {
+				printf STDERR "%-${width}s %s\n", "$k\->\{$k1\}", ${$val}{$k1};
+			}
+		} else {
+			printf STDERR "%-${width}s (-> %s)\n", $k, $ref;
+		}
+	}
+}
+
+1;
+