Re: [PATCH] ALSA: hda: Add hda_append_suffix() local helper

[Ian Bridges <icb@fastmail.org>]

On Thu, Jul 30, 2026 at 06:14:03PM +0200, Takashi Iwai wrote:
> As strlcat() shall be deprecated in future, provide an alternative
> just for a simple purpose -- append a suffix string to the given
> string buffer -- and use it at appropriate places.  The code isn't
> really efficient, but we don't ask for speed here, so let it be.

The patch was tested as follows:
 - Applied on today's for-next (f817bac425c5) on top of the two jack
 name cleanup patches. W=1 build of sound/hda/, no new warnings.

 - A userspace harness compared hda_append_suffix() against
 both the kernel strlcat() and the strncat() form in jack.c,
 exhaustively over buffer sizes, fill levels and suffix
 lengths, comparing every byte of the buffer. All cases
 were byte identical, including truncation.

 - A QEMU boot with intel-hda and hda-duplex, comparing the PCM
 stream names, the codec proc dump and the full control
 element list between base and patched kernels. The captures
 were byte identical.

Ian

Reviewed-by: Ian Bridges <icb@fastmail.org>
Tested-by: Ian Bridges <icb@fastmail.org>