=head1 NAME

Net::FastCGI::Protocol - Provides functions to build and parse FastCGI messages.

=head1 SYNOPSIS

    # FCGI_Header
    $octets = build_header($type, $request_id, $content_length, $padding_length);
    @values = parse_header($octets);
    
    # FCGI_BeginRequestBody
    $octets = build_begin_request_body($role, $flags);
    @values = parse_begin_request_body($octets);
    
    # FCGI_EndRequestBody
    $octets = build_end_request_body($application_status, $protocol_status);
    @values = parse_end_request_body($octets);
    
    # FCGI_UnknownTypeBody
    $octets = build_unknown_type_body($type);
    @values = parse_unknown_type_body($octets);
    
    # FCGI_BeginRequestRecord
    $octets = build_begin_request_record($request_id, $role, $flags);
    
    # FCGI_EndRequestRecord
    $octets = build_end_request_record($request_id, $application_status, $protocol_status);
    
    # FCGI_UnknownTypeRecord
    $octets = build_unknown_type_record($type);
    
    # FCGI_Record
    $octets = build_record($type, $request_id);
    $octets = build_record($type, $request_id, $content);
    
    # FCGI_NameValuePair's
    $octets = build_params($params);
    $params = parse_params($octets);
    
    # FCGI Byte Streams
    $octets = build_stream($type, $request_id, $octets);
    $octets = build_stream($type, $request_id, $octets, $terminate);

=head1 DESCRIPTION

Provides functions to build and parse FastCGI messages.

=head1 FUNCTIONS

=head2 build_begin_request_body

Builds a C<FCGI_BeginRequestBody>.

I<Usage>

    $octets = build_begin_request_body($role, $flags);

I<Arguments>

=over 4

=item C<$role>

An unsigned 16-bit integer.

=item C<$flags>

An unsigned 8-bit integer.

=back

I<Returns>

=over 4

=item C<$octets>

A string of octets containing the body. String is 8 octets in length.

=back

=head2 build_begin_request_record

Builds a C<FCGI_BeginRequestRecord>.

I<Usage>

    $octets = build_begin_request_record($request_id, $role, $flags);

I<Arguments>

=over 4

=item C<$request_id>

An unsigned 16-bit integer.

=item C<$role>

An unsigned 16-bit integer.

=item C<$flags>

An unsigned 8-bit integer.

=back

I<Returns>

=over 4

=item C<$octets>

A string of octets containing the record. String is 16 octets in length.

=back

=head2 build_end_request_body

Builds a C<FCGI_EndRequestBody>.

I<Usage>

    $octets = build_end_request_body($application_status, $protocol_status);

I<Arguments>

=over 4

=item C<$application_status>

An unsigned 32-bit integer.

=item C<$protocol_status>

An unsigned 8-bit integer.

=back

I<Returns>

=over 4

=item C<$octets>

A string of octets containing the body. String is 8 octets in length.

=back

=head2 build_end_request_record

Builds a C<FCGI_EndRequestRecord>.

I<Usage>

    $octets = build_end_request_record($request_id, $application_status, $protocol_status);

I<Arguments>

=over 4

=item C<$request_id>

An unsigned 16-bit integer.

=item C<$application_status>

An unsigned 32-bit integer.

=item C<$protocol_status>

An unsigned 8-bit integer.

=back

I<Returns>

=over 4

=item C<$octets>

A string of octets containing the record. String is 16 octets in length.

=back

=head2 build_header

Builds a C<FCGI_Header>.

I<Usage>

    $octets = build_header($type, $request_id, $content_length, $padding_length);

I<Arguments>

=over 4

=item C<$type>

An unsigned 8-bit integer.

=item C<$request_id>

An unsigned 16-bit integer.

=item C<$content_length>

An unsigned 16-bit integer.

=item C<$padding_length>

An unsigned 8-bit integer.

=back

I<Returns>

=over 4

=item C<$octets>

A string of octets containing the header. String is 8 octets in length.

=back

=head2 build_params

Builds C<FCGI_NameValuePair>'s.

I<Usage>

    $octets = build_params($params);

I<Arguments>

=over 4

=item C<$params>

A hash reference containing name/value pairs.

=back

I<Returns>

=over 4

=item C<$octets>

=back

=head2 build_record

Builds a C<FCGI_Record>.

I<Usage>

    $octets = build_record($type, $request_id);
    $octets = build_record($type, $request_id, $content);

I<Arguments>

=over 4

=item C<$type>

An unsigned 8-bit integer.

=item C<$request_id>

An unsigned 16-bit integer.

=item C<$content> (optional)

A string of octets containing the content, must be less than or equal to 65535 octets in length.

=back

I<Returns>

=over 4

=item C<$octets>

A string of octets containing the record.

=back

=head2 build_stream

Builds a series of byte streams records.

I<Usage>

    $octets = build_stream($type, $request_id, $content);
    $octets = build_stream($type, $request_id, $content, $terminate);

I<Arguments>

=over 4

=item C<$type>

An unsigned 8-bit integer.

=item C<$request_id>

An unsigned 16-bit integer.

=item C<$content>

A string of octets containing the stream content.

=item C<$terminate>

A boolean indicating whether or not the stream should be terminated.

=back

I<Returns>

=over 4

=item C<$octets>

A string of octets containing the stream.

=back

=head2 build_unknown_type_body

Builds a C<FCGI_UnknownTypeBody>.

I<Usage>

    $octets = build_unknown_type_body($type);

I<Arguments>

=over 4

=item C<$type>

An unsigned 8-bit integer.

=back

I<Returns>

=over 4

=item C<$octets>

A string of octets containing the body. String is 8 octets in length.

=back

=head2 build_unknown_type_record

Builds a C<FCGI_UnknownTypRecord>.

I<Usage>

    $octets = build_unknown_type_record($type);

I<Arguments>

=over 4

=item C<$type>

An unsigned 8-bit integer.

=back

I<Returns>

=over 4

=item C<$octets>

A string of octets containing the record. String is 16 octets in length.

=back

=head2 parse_begin_request_body

Parses a C<FCGI_BeginRequestBody>.

I<Usage>

    ($role, $flags) = parse_begin_request_body($octets);

I<Arguments>

=over 4

=item C<$octets>

A string of octets containing the body, must be greater than or equal to 8 octets in length.

=back

I<Returns>

=over 4

=item C<$role>

An unsigned 16-bit integer.

=item C<$flags>

An unsigned 8-bit integer.

=back

=head2 parse_end_request_body

Parses a C<FCGI_EndRequestBody>.

I<Usage>

    ($application_status, $protocol_status) = parse_end_request_body($octets);

I<Arguments>

=over 4

=item C<$octets>

A string of octets containing the body, must be greater than or equal to 8 octets in length.

=back

I<Returns>

=over 4

=item C<$application_status>

An unsigned 32-bit integer.

=item C<$flags>

An unsigned 8-bit integer.

=back

=head2 parse_header

Parses a C<FCGI_Header>.

I<Usage>

    ($type, $request_id, $content_length, $padding_length) = parse_header($octets);

I<Arguments>

=over 4

=item C<$octets>

A string of octets containing the header, must be greater than or equal to 8 octets in length.

=back

I<Returns>

=over 4

=item C<$type>

An unsigned 8-bit integer.

=item C<$request_id>

An unsigned 16-bit integer.

=item C<$content_length>

An unsigned 16-bit integer.

=item C<$padding_length>

An unsigned 8-bit integer.

=back

=head2 parse_params

Parses C<FCGI_NameValuePair>'s.

I<Usage>

    $params = parse_params($octets);

I<Arguments>

=over 4

=item C<$octets>

A string of octets containing C<FCGI_NameValuePair>'s.

=back

I<Returns>

=over 4

=item C<$params>

A hash reference containing name/value pairs.

=back

=head2 parse_unknown_type_body

Parses a C<FCGI_UnknownTypeBody>.

I<Usage>

    $type = parse_unknown_type_body($octets);

I<Arguments>

=over 4

=item C<$octets>

C<$octets> must be greater than or equal to 8 octets in length.

=back

I<Returns>

=over 4

=item C<$type>

An unsigned 8-bit integer.

=back

=head2 get_type_name

I<Usage>

    $name = get_type_name($type);

I<Arguments>

=over 4

=item C<$type>

An unsigned 8-bit integer.

=back

I<Returns>

=over 4

=item C<$name>

A string containing the name of the type.

=back

=head2 get_role_name

I<Usage>

    $name = get_role_name($type);

I<Arguments>

=over 4

=item C<$role>

An unsigned 16-bit integer.

=back

I<Returns>

=over 4

=item C<$name>

A string containing the name of the role.

=back

=head2 get_protocol_status_name

I<Usage>

    $name = get_protocol_status_name($protocol_status);

I<Arguments>

=over 4

=item C<$protocol_status>

An unsigned 8-bit integer.

=back

I<Returns>

=over 4

=item C<$name>

A string containing the name of the protocol status.

=back

=head2 is_known_type

I<Usage>

    $boolean = is_known_type($type);

I<Arguments>

=over 4

=item C<$type>

An unsigned 8-bit integer.

=back

I<Returns>

=over 4

=item C<$boolean>

A boolean indicating whether or not C<$type> is a known FastCGI v1 type.

=back

=head2 is_management_type

I<Usage>

    $boolean = is_management_type($type);

I<Arguments>

=over 4

=item C<$type>

An unsigned 8-bit integer.

=back

I<Returns>

=over 4

=item C<$boolean>

A boolean indicating whether or not C<$type> is a management type.

=back

=head2 is_discrete_type

I<Usage>

    $boolean = is_discrete_type($type);

I<Arguments>

=over 4

=item C<$type>

An unsigned 8-bit integer.

=back

I<Returns>

=over 4

=item C<$boolean>

A boolean indicating whether or not C<$type> is a discrete type.

=back

=head2 is_stream_type

I<Usage>

    $boolean = is_stream_type($type);

I<Arguments>

=over 4

=item C<$type>

An unsigned 8-bit integer.

=back

I<Returns>

=over 4

=item C<$boolean>

A boolean indicating whether or not C<$type> is a stream type.

=back

=head1 EXPORTS

None by default. All functions can be exported using the C<:all> tag or individually.

=head1 DIAGNOSTICS

=over 4

=item B<(F)> Usage: %s

=item B<(F)> Argument "%s" must be greater than or equal to %u octets in length

=item B<(F)> Argument "%s" must be less than or equal to %u octets in length

=item B<(F)> Unexpected end of octets while parsing FCGI_NameValuePair

=item B<(F)> Unsupported FastCGI version: %u

=back

=head1 SEE ALSO

=over 4

=item L<http://www.fastcgi.com/devkit/doc/fcgi-spec.html>

=item L<Net::FastCGI::Constant>


=back

=head1 AUTHOR

Christian Hansen C<chansen@cpan.org>

=head1 COPYRIGHT

Copyright (c) 2008 Christian Hansen. All rights reserved.

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