Re: [PATCH] vsprintf: sanely handle NULL passed to %pe
From: Ilya Dryomov <idryomov@gmail.com>
Date: 2020-02-19 11:29:35
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On Wed, Feb 19, 2020 at 12:25 PM Andy Shevchenko [off-list ref] wrote:
On Wed, Feb 19, 2020 at 1:21 PM Ilya Dryomov [off-list ref] wrote:quoted
On Wed, Feb 19, 2020 at 9:21 AM Rasmus Villemoes [off-list ref] wrote:quoted
Extend %pe to pretty-print NULL in addition to ERR_PTRs, i.e. everything IS_ERR_OR_NULL()....quoted
quoted
+ [0] = "NULL",quoted
quoted
+ test("[NULL]", "[%pe]", NULL);quoted
FWIW I was about to post a patch that just special cases NULL here. I think changing errname() to return "NULL" for 0 is overkill. People will sooner or later discover that function and start using it in contexts that don't have anything to do with pointers. Returning _some_ string for 0 (instead of NULL) makes it very close to standard strerror(), and "NULL" for 0 (i.e. success) seems rather odd.%pe is specifically for _pointers_. I don't see a point in your comment.
%pe is for pointers, but errname() in lib/errname.c will likely grow
more users in the future.
Thanks,
Ilya