sub template {
my ($self, $format) = @_;
# total (flattened) unpack template from nested format definitions
- return join '', map {
+ my $template = '';
+ @$format or return $template;
+ for (reverse 0 .. ($#$format - 1) >> 1) {
my $value = $format->[-($_ << 1) - 1];
if (ref $value eq 'ARRAY') {
my $count = $value->[0];
- $value = $self->template($value);
- $value = $count =~ s/^([*\d]+)// ? "$count($value)$1"
- : $count."X[$count]$count/($value)";
+ if ($count =~ /^\?/) {
+ $template .= 'a*';
+ last;
+ }
+ else {
+ $value = $self->template($value);
+ $value = $count =~ s/^([*\d]+)// ? "$count($value)$1"
+ : $count."X[$count]$count/($value)";
+ }
}
else {
$value =~ s/=(?:\d+|.)//g; # hardcoded values
$value =~ s{^C/(a)(\d+)}{$1 . ($2 + 1)}e; # maximum length
}
- $value;
- } reverse 0 .. ($#$format - 1) >> 1;
+ $template .= $value;
+ }
+ return $template;
}
sub convert {
my ($self, $format, $data, $pos) = @_;
# map flat results into a named and nested hash
my %res;
- $pos ||= \(my $_pos);
+ $pos ||= \(my $_pos = 0);
for (my $i = 0; $i < $#$format; $i += 2) {
my ($field, $template) = @$format[$i, $i+1];
if (ref $template eq 'ARRAY') {
my ($count, @subformat) = @$template;
+
+ if ($count =~ /^\?(\d+)/) {
+ # character-terminated group
+ my $endmark = chr $1;
+ my $iterate = ref($self)->new(\@subformat);
+ push @{ $iterate->[0] }, -pos => '=.';
+ my $subpos = 0;
+ while ($subpos < length $data->[0]) {
+ last if substr($data->[0], $subpos, 1) eq $endmark;
+ my $iterdata = $iterate->convert($iterate->[0], [
+ unpack $iterate->[1], substr($data->[0], $subpos)
+ ]) or last;
+ $subpos += delete $iterdata->{-pos};
+ push @{ $res{$field} }, $iterdata;
+ }
+ $$pos += $subpos + 1;
+ @$data = unpack(
+ $self->template([ @$format[$i+2 .. $#$format] ]),
+ substr($data->[0], $subpos + 1)
+ ) if $subpos < length $data->[0];
+ next;
+ }
+
$$pos++ if $count eq 'C';
my $max = $count =~ s/^(\d+)// ? $1 : 0;
$count = !$count ? $max