Re: Interfacing Ada with C

["Steve" <nospam_steved94@attbi.com>]

"Steve" <nospam_steved94@attbi.com> wrote in message
news:pD3na.499811$sf5.816502@rwcrnsc52.ops.asp.att.net...
> A different way of doing this:
>
> In Ada you should be able to use Interfaces.C.Pointers and then declare
your
> procedure as follows:
>
>   package Interface_Wide_String is
>     new Interfaces.C.Pointers( Interfaces.C.size_T,
>                                Interfaces.C.WChar_T,
>                                Interfaces.C.WChar_Array,
>                                Interfaces.C.Wide_Nul );
[snip]
>
> I haven't tested this, but I think it will work (it compiles anyway).
>
> Steve
> (The Duck)
>
I created a small set of sources and tested my example (it does work).
Here's the source
for my test case:

------ File: clatest.c ------
#include <stdlib.h>

extern void One( wchar_t *text );
extern void adainit();
extern void adafinal();

int main(int argc, char* argv[])
{
    adainit();
    One( L"Hello from Ada" );
    adafinal();
    return 0;
}

------ File: One_Package.ads ------
with Interfaces.C;
with Interfaces.C.Pointers;

package One_Package is

  package Interface_Wide_String is
    new Interfaces.C.Pointers( Interfaces.C.size_T,
                               Interfaces.C.WChar_T,
                               Interfaces.C.WChar_Array,
                               Interfaces.C.Wide_Nul );

  procedure One( Name : in Interface_Wide_String.Pointer );
  pragma Export( C, One, "One" );

end One_Package;

------ File: One_Package.adb ------
with Ada.Wide_Text_Io;

package body One_Package is

  procedure One( Name : in Interface_Wide_String.Pointer ) is
  begin
    Ada.Wide_Text_Io.Put_Line( Interfaces.C.To_Ada(
Interface_Wide_String.Value( Name ) ) );
  end One;

end One_Package;

Steve
(The Duck)