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From: Jeffrey Carter <spam.jrcarter.not@spam.not.acm.org>
Newsgroups: comp.lang.ada
Subject: Re: Interface with C codes
Date: Fri, 17 Oct 2014 19:20:42 -0700
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Xref: news.eternal-september.org comp.lang.ada:22563
Date: 2014-10-17T19:20:42-07:00
List-Id: <comp.lang.ada>

On 10/17/2014 04:22 PM, Anh Vo wrote:
> What Ada spec should be for the following C prototype where BOOT_PARAMS is a struct and responding Ada type is
> 
> type Boot_Parameter_Type is
>    record
>       Boot_Dev : Interfaces.C.Strings.Chars_Ptr;

This doesn't match the C quoted below. Use

                   Interfaces.C.Char_Array (0 .. 19);

>       -- ...
>    end record;
> pragma Convention (C, Boot_Parameter_Type);
> 
> type Boot_Parameter_Type_Access is access Boot_Parameter_Type;
> pragma Convention (C, Boot_Parameter_Type_Access);

You don't need this access type.

> char *  bootStringToStruct (char * bootString,  BOOT_PARAMS * pBootParams);

I would probably use

function To_Record
(Boot_String : Intefaces.C.Char_Array; Boot_Parameter : Boot_Parameter_Type)
return Interfaces.C.Strings.Chars_Ptr;

and rely on the advice in B.3(69-70): both parameters will be passed by reference.

-- 
Jeff Carter
"Whatever it is, I'm against it."
Horse Feathers
46