[U-Boot] [PATCH V2] memcpy/memmove: Do not copy to same address

Mike Frysinger
2011-05-24T03:47:01Z

On Monday, May 23, 2011 18:38:49 Alexander Holler wrote:
> Am 24.05.2011 00:22, schrieb Wolfgang Denk:
> > Alexander Holler wrote:
> >> So you I will look forward to checks for NULL pointers and similiar in
> >> all C standard functions implemented in u-boot to circumvent tons of
> >> possible real world bugs in all callers of strcpy, strlen, mem* and
> >> whatever.
> >
> > If you think a bit about this, you may find it more difficult than you
> > expect. Keep in mind that on most systems supported by U-Boot code
> > like
> >
> > int *p = (int *)0;
> >
> > print("*p = %d\n", *p);
> >
> > is perfectly legal and supposed to work without any problems -
> > because 0 is a legal address, and it makes perfect senze that commands
> > like "md" or "cp" can be used to access it. In the result, strcpy(),
> > strlen(), mem*() and whatever must beable to work on address 0 likeon
> > any other address, too.
>
> I've never seen a valid use of strcpy() with a null-pointer in real
> world programs, which we are talking about, except in bugs.

i'm lazy and type "0" all the time for loading files, copying memory,
displaying things, etc... in u-boot. i dont feel like retraining my finger
muscle memory if i dont have to ;).
-mike
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