Re: Ada array vs C pointer (call by reference)

[Adrian Hoe <abyhoe@gmail.com>]

On Jun 27, 9:39 am, Adrian Hoe <aby...@gmail.com> wrote:
> Hi,
>
> I have a C library function which takes a float * as a parameter. The
> function is as below:
>
>    int pwmRead (int pwmCount, float * data);
>
> where data is an array of float which size is determined by pwmCount.
>
> In Ada, I have:
>
>    PWM_Count : Integer := No_Of_Components_Intended;
>    PWM_Data : array (1 .. PWM_Count) of Float;
>
> My concern is how safe to pass an Ada array to a C function as a
> pointer (call by reference)? I presume Ada will allocate contiguous
> memory for array, but what if it does not? How can we establish a
> deterministic allocation and to make sure float * is accessed
> contiguously? Is there any "safe" way to do this?
>
> Thanks.
> --
> Adrian Hoehttp://adrianhoe.com


Sorry, PWM_Count should be declared as constant:

   PWM_Count : constant := No_Of_Components_Intended;