From: Mischa Poslawsky <wormy@shiar.org>
Date: Tue, 3 Mar 2009 22:15:53 +0000 (+0100)
Subject: Parse::Binary::Nested: simple non-OO unpackf
X-Git-Url: http://git.shiar.nl/wormy.git/commitdiff_plain/f4886cc6c2159afd00025585fcc6ea7aac820391

Parse::Binary::Nested: simple non-OO unpackf

Make the unpackf method callable without an object, taking a template
array instead.  This turns it into a simple superset of CORE::unpack()
for most usage.  The object-oriented syntax is still supported for
reusable parsing (saves reparsing the template on each call, so should
also be slightly faster).
---

diff --git a/Parse/Binary/Nested.pm b/Parse/Binary/Nested.pm
index 371a65b..75c22fa 100644
--- a/Parse/Binary/Nested.pm
+++ b/Parse/Binary/Nested.pm
@@ -5,14 +5,18 @@ use strict;
 use warnings;
 
 use Carp;
+use Exporter qw(import);
 
-our $VERSION = '1.02';
+our $VERSION = '1.10';
+our @EXPORT_OK = qw(unpackf);
 
 sub new {
 	my ($class, $format) = @_;
+	ref $format
+		or $format = [0 => $format];
 	ref $format eq 'ARRAY'
 		or croak "Invalid Parse::Binary::Nested format: should be an array ref";
-	bless $format, $class;
+	bless [$format, $class->template($format)], $class;
 }
 
 sub template {
@@ -39,14 +43,15 @@ sub convert {
 	# map flat results into a named and nested hash
 	my %res;
 	$pos ||= \(my $_pos);
-	while (my ($field, $template) = splice @$format, 0, 2) {
+	for (my $i = 0; $i < $#$format; $i += 2) {
+		my ($field, $template) = @$format[$i, $i+1];
 		if (ref $template eq 'ARRAY') {
 			my ($count, @subformat) = @$template;
 			$$pos++ if $count eq 'C';
 			my $max = $count =~ s/^(\d+)// ? $1 : 0;
 			$count = !$count ? $max
 				: $count eq '*' ? $res{levelcount}->{total} : shift @$data;
-			$res{$field}->[$_] = $self->convert([@subformat], $data, $pos)
+			$res{$field}->[$_] = $self->convert(\@subformat, $data, $pos)
 				for 0 .. ($max || $count)-1;
 			splice @{ $res{$field} }, $count if $max > $count;
 			$res{$field} = $res{$field}->[0] if $max == 1;
@@ -108,9 +113,11 @@ sub convert {
 }
 
 sub unpackf {
-	my ($self, $input) = @_;
-	my @data = unpack $self->template($self), $input;
-	return $self->convert([@$self], \@data);
+	my ($format, $input) = @_;
+	my $self = UNIVERSAL::isa($format, __PACKAGE__) ? $format
+		: __PACKAGE__->new($format);
+	my @data = unpack $self->[1], $input;
+	return $self->convert($self->[0], \@data);
 }
 
 1;
@@ -121,7 +128,9 @@ Parse::Binary::Nested - Structured unpack
 
 =head1 SYNOPSIS
 
-	use Parse::Binary::Nested;
+	use Parse::Binary::Nested qw(unpackf);
+	my $data = unpackf([message => 'Z*'], "hi\0");
+
 	my $parser = Parser::Binary::Nested->new([
 		foos => [
 			'C', # count
@@ -130,8 +139,7 @@ Parse::Binary::Nested - Structured unpack
 		],
 		trail => 'a*',
 	]);
-	
-	my $data = $parser->unpackf("\1foo\0.rest");
+	$data = $parser->unpackf("\1foo\0.rest");
 	print $data->{foos}->[0]->{message};
 
 =head1 DESCRIPTION
diff --git a/parse-wormedit b/parse-wormedit
index 585c03a..ed64118 100755
--- a/parse-wormedit
+++ b/parse-wormedit
@@ -19,7 +19,7 @@ package Shiar_Parse::WormEdit;
 use strict;
 use warnings;
 
-use Parse::Binary::Nested;
+use Parse::Binary::Nested qw(unpackf);
 
 our %MAGICID = (
 	"WormEdit053\000LVL" => 53,
@@ -153,7 +153,7 @@ sub read {
 
 	# convert to an easily accessible hash
 	push @FORMAT, -trail => 'a*';
-	my $data = Parse::Binary::Nested->new(\@FORMAT)->unpackf($input);
+	my $data = unpackf(\@FORMAT, $input);
 	warn "Trailing data left unparsed\n" if length delete $data->{-trail};
 	$data->{format} = 'WormEdit';
 	return $data;
@@ -167,7 +167,7 @@ use warnings;
 
 use List::Util qw(sum min max);
 use Data::Dumper;
-use Parse::Binary::Nested;
+use Parse::Binary::Nested qw(unpackf);
 
 sub read {
 	my ($self, $input) = @_;
@@ -293,7 +293,7 @@ sub read {
 		}
 	}
 
-	my $data = Parse::Binary::Nested->new(\@FORMAT)->unpackf($input);
+	my $data = unpackf(\@FORMAT, $input);
 	my $offset = 0;
 	$offsetbase += 1 + @{ $data->{sprite} } if $data->{sprite};
 	$data->{moderef}->{offset}->{single} == $offsetbase
diff --git a/t/parser.t b/t/parser.t
index 5e53315..faa229c 100644
--- a/t/parser.t
+++ b/t/parser.t
@@ -6,35 +6,53 @@ use warnings;
 use Test::More;
 use Data::Dumper;
 
-plan tests => 6;
+plan tests => 7;
 
 use_ok('Parse::Binary::Nested');
 
-my $example = Parse::Binary::Nested->new([
+my @example = (
 	foos => [
 		'C',
 		message => 'Z*',
-		period  => 'C',
+		period  => 'a',
 	],
 	trail => 'a*',
-]);
-ok($example, 'example parser');
-my $data = $example->unpackf("\2foo\0!\0.rest");
-is(ref $data, 'HASH', 'output structure');
-is($data->{foos}->[1]->{period}, ord '.', 'sample element');
+);
+my $testdata = "\2foo\0!\0.rest";
+my $testresult = {
+	foos => [
+		{message => 'foo', period => '!'},
+		{message => '',    period => '.'},
+	],
+	trail => 'rest',
+};
+
+my $parser = Parse::Binary::Nested->new(\@example);
+ok($parser, 'new object');
+is_deeply($parser->unpackf($testdata), $testresult, 'object unpackf');
+
+Parse::Binary::Nested->import('unpackf');
+is_deeply(
+	unpackf(\@example, $testdata),
+	$testresult,
+	'unprepared unpackf'
+);
+
+my @commonargs = ('cxaXv', "\1\2hi\0");
+is_deeply(
+	[ values %{ unpackf(@commonargs) } ],
+	[[ unpack($commonargs[0], $commonargs[1]) ]],
+	'unpack compatibility'
+);
 
 is_deeply(
-	Parse::Binary::Nested->new(
-		[ lstr => 'Ca3', rest => 'a*' ]
-	)->unpackf("\2quux"),
+	unpackf([ lstr => 'C/a3', rest => 'a*' ], "\2quux"),
 	{ lstr => 'qu', rest => 'x' },
 	'length string'
 );
 
 is_deeply(
-	Parse::Binary::Nested->new(
-		[ ignoreme => 'x2X', value => 'xC' ]
-	)->unpackf("\0\1\2"),
+	unpackf([ ignoreme => 'x2X', value => 'xC' ], "\0\1\2"),
 	{ value => 2 },
 	'empty values'
 );