Ticket 4503

[zack leung]

bump

On Thu, 9 Sept 2021 at 02:17, zack leung <zakthertemsdev at gmail.com> wrote:

> >Thanks! I guess i'm really unsure about how the pointer relates to the
> amount of memory that you can use. I assume the Malloc keeps track of the
> sections being used in the heap. Does this function Allocate 2 blocks since
> the pointer is set to
>
> (uintptr_t) next_block + HEAP_ALLOC_BONUS - alloc_begin;
>
> >(I know it's a bit naive to assume this given my first question)
>
> think the method is _Heap_Size_of_alloc_area. It may need a wrapper added
> to the protected heap wrapper for safety. I don't know if it has one. It
> should be the equivalent functionality.
> > How would i implement a wrapper and what safety measures need to be
> implemented. So far it's checking if :  the block is not in the heap and if
> it's been previously used. Is the usable memory in the heap calculated by:
> the size of the block * # of blocks?
>
> Thanks, Zack
>
> ---------- Forwarded message ---------
> From: Joel Sherrill <joel at rtems.org>
> Date: Wed, 8 Sept 2021 at 20:30
> Subject: Re: Ticket 4503
> To: Gedare Bloom <gedare at rtems.org>
> Cc: zack leung <zakthertemsdev at gmail.com>, rtems-devel at rtems.org <
> devel at rtems.org>
>
>
>
>
> On Wed, Sep 8, 2021 at 11:02 AM Gedare Bloom <gedare at rtems.org> wrote:
>
>> Hi Zack,
>>
>> https://devel.rtems.org/ticket/4503
>>
>> The malloc implementation exists in the score as the Heap Manager. search
>> for "Heap_" within cpukit to get some ideas where to look.
>>
>
> I think the method is _Heap_Size_of_alloc_area. It may need a wrapper
> added to the protected heap wrapper for safety. I don't know if it has one.
> It should be the equivalent functionality.
>
> newlib's malloc.h will need looking at to make sure we provide the right
> methods.
>
>
>
>>
>> @Joel are these two tickets duplicates?
>> https://devel.rtems.org/ticket/4503
>> https://devel.rtems.org/ticket/4271
>>
>
> Yes. Closed #4271 and merged comments.
>
> --joel
>
>
>>
>>
>> -Gedare
>>
>> On Tue, Sep 7, 2021 at 7:14 PM zack leung <zakthertemsdev at gmail.com>
>> wrote:
>>
>>> I was wondering about ticket 4503. I was wondering where The required
>>> functionality should be in the underlying score/ capability used can be
>>> found to write this function. Also how does this relate  to
>>>
>>> Add common malloc family extension method malloc_usable_size()
>>> <https://devel.rtems.org/ticket/4271>?
>>> Thanks
>>> Zack
>>> _______________________________________________
>>> devel mailing list
>>> devel at rtems.org
>>> http://lists.rtems.org/mailman/listinfo/devel
>>
>>