joel.sherrill at OARcorp.com
Thu Apr 19 18:44:00 UTC 2012
On 04/19/2012 01:59 AM, Sebastian Huber wrote:
> On 04/18/2012 05:54 PM, Joel Sherrill wrote:
>> On 04/18/2012 10:33 AM, Sebastian Huber wrote:
>>> On 04/18/2012 04:59 PM, Joel Sherrill wrote:
>>>> copyinstr is currently undefined. According to cscope,
>>>> it is only defined in
>>>> in the source we are using. But when I look where it is
>>>> referenced in rtems-libbsd, it should have a generic
>>>> implementation. And these files have much more than this
>>>> one routine.
>>>> Any thoughts?
>>> I think these are the user/kernel space copy routines. Do we need them at all?
>> My gut was that we could have our own implementation which
>> called memcpy. We don't have user/kernel space but it does appear
>> to be copying data.
> These functions are documented here:
> Maybe it is sufficient so simply assign the kernel address to the user pointer
> and vice versa?
From the man page linked to...
The copy functions are designed to copy contiguous data from one address
to another. All but copystr() copy data from user-space to kernel-space
I propose we implement those needed with memmove() in case the
addresses are overlapping.
If the source and destination addresses are the same, then
we could just return and avoid it. I don't know if this happens though.
But memmove() is save.
Joel Sherrill, Ph.D. Director of Research& Development
joel.sherrill at OARcorp.com On-Line Applications Research
Ask me about RTEMS: a free RTOS Huntsville AL 35805
Support Available (256) 722-9985
More information about the devel