Re: How to bind this properly, C ** which is an array

["Björn Lundin" <b.f.lundin@gmail.com>]

On 2019-03-01 14:48, Lucretia wrote:
> Hi,
> 
> I'm trying to bind the following struct:
> 
> typedef struct mpc_ast_t {
>   char *tag;
>   char *contents;
>   mpc_state_t state;
>   int children_num;
>   struct mpc_ast_t** children;
> } mpc_ast_t;
> 
> I have this:
> 
>    type ASTs is
>    record
>       Tag                : C.Strings.chars_ptr;
>       Contents           : C.Strings.chars_ptr;
>       State              : States;
>       Number_Of_Children : C.int;
>       Children           : System.Address; --  Pointer to a pointer to an array of ASTs.
>    end record with
>      Convention => C;
> 
> Children needs to be accessed in code as a pointer to a pointer to an array of ASTs.
> 
> How do I best bind this thing? It's likely going to have to be converted from Address to a particular type using Unchecked_Conversion most likely.
> 
> Thanks,
> Luke.
> 

naïvly I would have tried something like

 type Ptr_To_Chars_Ptr is access all C.Strings.chars_ptr;

    type ASTs is
    record
       Tag                : C.Strings.chars_ptr;
       Contents           : C.Strings.chars_ptr;
       State              : States;
       Number_Of_Children : C.int;
       Children           : Ptr_To_Chars_Ptr;
    end record with
      Convention => C;


-- 
--
Björn