Re: Binding to C

["Patrice Freydiere" <frett27@free.fr>]

Chris, if you are looking for building a complete full Jpeg binding, 
your can browse the AGP project (ada game programming)
it contains a jpeg binding, and a PNG binding.

so it can gives you some ideas for C binding from ADA.

hope this help.
Patrice

ps: when i started writing the simplejpeglib binding for ADA.
i had a lot of interfacing problems du to the portability macros of the
jpeglib. (it's surely possible, but when i've started my binding, my C
interfacing Skills from ADA was poor).
So i decided in my design to build a simple C interface to make Ada
binding easier. This permit me to be "C structure independent" and provide a
more easy upgrade of the jpeglib.


On Mon, 21 Jul 2003 20:59:30 +0200, chris wrote:

> Hi,
> 
> I came across the following in libjpeg... what should I map it to?
> 
> const char* const* jpeg_message_table
> 
> Also does anyone have any advice in general mapping to C.  For the 
> jpeg_error_mgr struct, I mapped ptrs to functions to System.Address and 
> made the struct a record.  Will this work, or will the corresponding 
> type of the struct have to be a System.Address?
> 
> 
> Chris
> 
> package Low_Jpg.Error is
> 
>     package C renames Interfaces.C;
> 
>     type Jpeg_Error_Mgr is record
>        Error_Exit      : System.Address; -- addr of a handler
>        Emit_Message    : System.Address;
>        Output_Message  : System.Address;
>        Format_Message  : System.Address;
>        Reset_Error_Mgr : System.Address;
>        Msg_Code        : C.Int;
>        Msg_Parm        : System.Address;
>        Trace_Level     : C.Int;
>        Num_Warnings    : C.Long;
>     end record;
>     pragma Convention (C, Jpeg_Error_Mgr);
> 
> end Low_Jpg.Error;