README

NAME

    FFI::Platypus::Lang::Pascal - Documentation and tools for using
    Platypus with the Free Pascal programming language

SYNOPSIS

    Free Pascal:

     { compile and link with: fpc mylib.pas }
     
     Library MyLib;
     
     Function Add(A: Integer; B: Integer): Integer; Cdecl;
     Begin
       Add := A + B;
     End;
     
     Exports
       Add;
     
     End.

    Perl:

     use FFI::Platypus;
     
     my $ffi = FFI::Platypus->new;
     $ffi->lang('Pascal');
     $ffi->lib('./libmylib.so');
     
     $ffi->attach(
       Add => ['Integer','Integer'] => 'Integer'
     );
     
     print Add(1,2), "\n";

DESCRIPTION

    This modules provides native types and demangling for the Free Pascal
    Programming language when used with FFI::Platypus.

    This module provides these types (case sensitive):

    Byte

    ShortInt

    SmallInt

    Word

    Integer

      This is an alias for SmallInt (which is appropriate for Free Pascal's
      default mode)

    Cardinal

    LongInt

    LongWord

    Int64

    QWord

    Boolean

    ByteBool

    WordBool

    LongBool

    Single

    Double

    The following types are not (yet) supported:

    Extended

    Comp

    Currency

    ShortString

    This module also has some support for demangled functions and
    overloading, if you are using a dynamic library constructed from units
    via ppumove.

    You may also use Module::Build::FFI::Pascal to bundle Free Pascal code
    with your distribution.

CAVEATS

    I've been experimenting with Free Pascal 2.6.0 while working on this
    module.

 name mangling

    If you compile one or more Pascal Units and link them using ppumove,
    they symbols in the resulting dynamic library will include mangled
    Pascal names. This module has at least some support for such names.

    For example, suppose you had this Pascal Unit:

     Unit Add;
     
     Interface
     
     Function Add( A: SmallInt; B: SmallInt) : SmallInt; Cdecl;
     Function Add( A: Real;    B: Real)      : Real; Cdecl;
     
     Implementation
     
     Function Add( A: SmallInt; B: SmallInt) : SmallInt; Cdecl;
     Begin
       Add := A + B;
     End;
     
     Function Add( A: real; B: real) : real; Cdecl;
     Begin
       Add := A + B;
     End;
     
     End.

    On Linux, you could compile and link this into a shared object with
    these commands:

     fpc add.pas
     gcc -o add.so -shared add.o

    And you could then use it from Perl:

     use FFI::Platypus;
     
     my $ffi = FFI::Platypus->new;
     $ffi->lang('Pascal');
     $ffi->lib('./add.so');
     
     $ffi->attach(
       ['Add.Add(SmallInt,SmallInt):SmallInt' => 'Add'] => ['SmallInt','SmallInt'] => 'SmallInt'
     );
     
     print Add(1,2), "\n";

    When attaching the function you have to specify the argument and return
    types because the Add function is overloaded and is ambiguous without
    it. If there were just one Add function, then you could attach it like
    this:

     $ffi->attach('Add' => ['SmallInt','SmallInt'] => 'SmallInt');

    The downside to using a shared library constructed from Pascal Units in
    this way is that the resulting dynamic library does not include the
    Pascal standard library so very simple capabilities such as IO and
    ShortString are not available. It is recommended instead to use a
    Pascal Library (possibly linked with one or more Pascal Units), as
    inthe "SYNOPSIS" at the top.

METHODS

    Generally you will not use this class directly, instead interacting
    with the FFI::Platypus instance. However, the public methods used by
    Platypus are documented here.

 native_type_map

     my $hashref = FFI::Platypus::Lang::Pascal->native_type_map;

    This returns a hash reference containing the native aliases for the
    Free Pascal programming languages. That is the keys are native Pascal
    types and the values are libffi native types.

    Types are in camel case. For example use ShortInt, not Shortint or
    SHORTINT.

 mangler

     my $mangler = FFI::Platypus::Lang::Pascal->mangler($ffi->libs);
     # prints ADD_ADD$SMALLINT$SMALLINT$$SMALLINT
     print $mangler->("add(smallint,smallint):smallint");

    Returns a subroutine reference that will "mangle" Pascal names.

EXAMPLES

    See the above "SYNOPSIS" or the examples directory that came with this
    distribution.

SUPPORT

    If something does not work as advertised, or the way that you think it
    should, or if you have a feature request, please open an issue on this
    project's GitHub issue tracker:

    https://github.com/PerlFFI/FFI-Platypus-Lang-Pascal/issues

    This project's GitHub issue tracker listed above is not Write-Only. If
    you want to contribute then feel free to browse through the existing
    issues and see if there is something you feel you might be good at and
    take a whack at the problem. I frequently open issues myself that I
    hope will be accomplished by someone in the future but do not have time
    to immediately implement myself.

    Another good area to help out in is documentation. I try to make sure
    that there is good document coverage, that is there should be
    documentation describing all the public features and warnings about
    common pitfalls, but an outsider's or alternate view point on such
    things would be welcome; if you see something confusing or lacks
    sufficient detail I encourage documentation only pull requests to
    improve things.

CONTRIBUTING

    If you have implemented a new feature or fixed a bug then you may make
    a pull reequest on this project's GitHub repository:

    https://github.com/PerlFFI/FFI-Platypus-Lang-Pascal/pulls

SEE ALSO

    FFI::Platypus

      The Core Platypus documentation.

    Module::Build::FFI::Pascal

      Bundle Free Pascal with your FFI / Perl extension.

AUTHOR

    Graham Ollis <plicease@cpan.org>

COPYRIGHT AND LICENSE

    This software is copyright (c) 2015 by Graham Ollis.

    This is free software; you can redistribute it and/or modify it under
    the same terms as the Perl 5 programming language system itself.