ZX Spectrum tape file: Perl parsing library

TAP files are used by emulators of ZX Spectrum computer (released in 1982 by Sinclair Research). TAP file stores blocks of data as if they are written to magnetic tape, which was used as primary media for ZX Spectrum. Contents of this file can be viewed as a very simple linear filesystem, storing named files with some basic metainformation prepended as a header.

File extension

tap

KS implementation details

License: CC0-1.0

References

This page hosts a formal specification of ZX Spectrum tape file using Kaitai Struct. This specification can be automatically translated into a variety of programming languages to get a parsing library.

Perl source code to parse ZX Spectrum tape file

ZxSpectrumTap.pm

Download 

# This is a generated file! Please edit source .ksy file and use kaitai-struct-compiler to rebuild

use strict;
use warnings;
use IO::KaitaiStruct 0.009_000;

########################################################################
package ZxSpectrumTap;

our @ISA = 'IO::KaitaiStruct::Struct';

sub from_file {
    my ($class, $filename) = @_;
    my $fd;

    open($fd, '<', $filename) or return undef;
    binmode($fd);
    return new($class, IO::KaitaiStruct::Stream->new($fd));
}

our $FLAG_ENUM_HEADER = 0;
our $FLAG_ENUM_DATA = 255;

our $HEADER_TYPE_ENUM_PROGRAM = 0;
our $HEADER_TYPE_ENUM_NUM_ARRAY = 1;
our $HEADER_TYPE_ENUM_CHAR_ARRAY = 2;
our $HEADER_TYPE_ENUM_BYTES = 3;

sub new {
    my ($class, $_io, $_parent, $_root) = @_;
    my $self = IO::KaitaiStruct::Struct->new($_io);

    bless $self, $class;
    $self->{_parent} = $_parent;
    $self->{_root} = $_root || $self;;

    $self->_read();

    return $self;
}

sub _read {
    my ($self) = @_;

    $self->{blocks} = ();
    while (!$self->{_io}->is_eof()) {
        push @{$self->{blocks}}, ZxSpectrumTap::Block->new($self->{_io}, $self, $self->{_root});
    }
}

sub blocks {
    my ($self) = @_;
    return $self->{blocks};
}

########################################################################
package ZxSpectrumTap::Block;

our @ISA = 'IO::KaitaiStruct::Struct';

sub from_file {
    my ($class, $filename) = @_;
    my $fd;

    open($fd, '<', $filename) or return undef;
    binmode($fd);
    return new($class, IO::KaitaiStruct::Stream->new($fd));
}

sub new {
    my ($class, $_io, $_parent, $_root) = @_;
    my $self = IO::KaitaiStruct::Struct->new($_io);

    bless $self, $class;
    $self->{_parent} = $_parent;
    $self->{_root} = $_root || $self;;

    $self->_read();

    return $self;
}

sub _read {
    my ($self) = @_;

    $self->{len_block} = $self->{_io}->read_u2le();
    $self->{flag} = $self->{_io}->read_u1();
    if ( (($self->len_block() == 19) && ($self->flag() == $ZxSpectrumTap::FLAG_ENUM_HEADER)) ) {
        $self->{header} = ZxSpectrumTap::Header->new($self->{_io}, $self, $self->{_root});
    }
    if ($self->len_block() == 19) {
        $self->{data} = $self->{_io}->read_bytes(($self->header()->len_data() + 4));
    }
    if ($self->flag() == $ZxSpectrumTap::FLAG_ENUM_DATA) {
        $self->{headerless_data} = $self->{_io}->read_bytes(($self->len_block() - 1));
    }
}

sub len_block {
    my ($self) = @_;
    return $self->{len_block};
}

sub flag {
    my ($self) = @_;
    return $self->{flag};
}

sub header {
    my ($self) = @_;
    return $self->{header};
}

sub data {
    my ($self) = @_;
    return $self->{data};
}

sub headerless_data {
    my ($self) = @_;
    return $self->{headerless_data};
}

########################################################################
package ZxSpectrumTap::ProgramParams;

our @ISA = 'IO::KaitaiStruct::Struct';

sub from_file {
    my ($class, $filename) = @_;
    my $fd;

    open($fd, '<', $filename) or return undef;
    binmode($fd);
    return new($class, IO::KaitaiStruct::Stream->new($fd));
}

sub new {
    my ($class, $_io, $_parent, $_root) = @_;
    my $self = IO::KaitaiStruct::Struct->new($_io);

    bless $self, $class;
    $self->{_parent} = $_parent;
    $self->{_root} = $_root || $self;;

    $self->_read();

    return $self;
}

sub _read {
    my ($self) = @_;

    $self->{autostart_line} = $self->{_io}->read_u2le();
    $self->{len_program} = $self->{_io}->read_u2le();
}

sub autostart_line {
    my ($self) = @_;
    return $self->{autostart_line};
}

sub len_program {
    my ($self) = @_;
    return $self->{len_program};
}

########################################################################
package ZxSpectrumTap::BytesParams;

our @ISA = 'IO::KaitaiStruct::Struct';

sub from_file {
    my ($class, $filename) = @_;
    my $fd;

    open($fd, '<', $filename) or return undef;
    binmode($fd);
    return new($class, IO::KaitaiStruct::Stream->new($fd));
}

sub new {
    my ($class, $_io, $_parent, $_root) = @_;
    my $self = IO::KaitaiStruct::Struct->new($_io);

    bless $self, $class;
    $self->{_parent} = $_parent;
    $self->{_root} = $_root || $self;;

    $self->_read();

    return $self;
}

sub _read {
    my ($self) = @_;

    $self->{start_address} = $self->{_io}->read_u2le();
    $self->{reserved} = $self->{_io}->read_bytes(2);
}

sub start_address {
    my ($self) = @_;
    return $self->{start_address};
}

sub reserved {
    my ($self) = @_;
    return $self->{reserved};
}

########################################################################
package ZxSpectrumTap::Header;

our @ISA = 'IO::KaitaiStruct::Struct';

sub from_file {
    my ($class, $filename) = @_;
    my $fd;

    open($fd, '<', $filename) or return undef;
    binmode($fd);
    return new($class, IO::KaitaiStruct::Stream->new($fd));
}

sub new {
    my ($class, $_io, $_parent, $_root) = @_;
    my $self = IO::KaitaiStruct::Struct->new($_io);

    bless $self, $class;
    $self->{_parent} = $_parent;
    $self->{_root} = $_root || $self;;

    $self->_read();

    return $self;
}

sub _read {
    my ($self) = @_;

    $self->{header_type} = $self->{_io}->read_u1();
    $self->{filename} = IO::KaitaiStruct::Stream::bytes_strip_right($self->{_io}->read_bytes(10), 32);
    $self->{len_data} = $self->{_io}->read_u2le();
    my $_on = $self->header_type();
    if ($_on == $ZxSpectrumTap::HEADER_TYPE_ENUM_PROGRAM) {
        $self->{params} = ZxSpectrumTap::ProgramParams->new($self->{_io}, $self, $self->{_root});
    }
    elsif ($_on == $ZxSpectrumTap::HEADER_TYPE_ENUM_NUM_ARRAY) {
        $self->{params} = ZxSpectrumTap::ArrayParams->new($self->{_io}, $self, $self->{_root});
    }
    elsif ($_on == $ZxSpectrumTap::HEADER_TYPE_ENUM_CHAR_ARRAY) {
        $self->{params} = ZxSpectrumTap::ArrayParams->new($self->{_io}, $self, $self->{_root});
    }
    elsif ($_on == $ZxSpectrumTap::HEADER_TYPE_ENUM_BYTES) {
        $self->{params} = ZxSpectrumTap::BytesParams->new($self->{_io}, $self, $self->{_root});
    }
    $self->{checksum} = $self->{_io}->read_u1();
}

sub header_type {
    my ($self) = @_;
    return $self->{header_type};
}

sub filename {
    my ($self) = @_;
    return $self->{filename};
}

sub len_data {
    my ($self) = @_;
    return $self->{len_data};
}

sub params {
    my ($self) = @_;
    return $self->{params};
}

sub checksum {
    my ($self) = @_;
    return $self->{checksum};
}

########################################################################
package ZxSpectrumTap::ArrayParams;

our @ISA = 'IO::KaitaiStruct::Struct';

sub from_file {
    my ($class, $filename) = @_;
    my $fd;

    open($fd, '<', $filename) or return undef;
    binmode($fd);
    return new($class, IO::KaitaiStruct::Stream->new($fd));
}

sub new {
    my ($class, $_io, $_parent, $_root) = @_;
    my $self = IO::KaitaiStruct::Struct->new($_io);

    bless $self, $class;
    $self->{_parent} = $_parent;
    $self->{_root} = $_root || $self;;

    $self->_read();

    return $self;
}

sub _read {
    my ($self) = @_;

    $self->{reserved} = $self->{_io}->read_u1();
    $self->{var_name} = $self->{_io}->read_u1();
    $self->{reserved1} = $self->{_io}->read_bytes(2);
}

sub reserved {
    my ($self) = @_;
    return $self->{reserved};
}

sub var_name {
    my ($self) = @_;
    return $self->{var_name};
}

sub reserved1 {
    my ($self) = @_;
    return $self->{reserved1};
}

1;