[PATCH v2 04/12] sysinfo: Make sysinfo_get_str() behave like snprintf()

[Simon Glass]

Hi Marek,

On Wed, 3 Nov 2021 at 17:23, Marek Behún <kabel at kernel.org> wrote:
>
> From: Marek Behún <marek.behun at nic.cz>
>
> Currently sysinfo_get_str() returns 0 if a string is filled in the
> given buffer, and otherwise gives no simple mechanism to determine
> actual string length.
>
> One implementation returns -ENOSPC if buffer is not large enough.
>
> Change the behaviour of the function to that of snprintf(): i.e. the
> buffer is always filled in as much as possible if the string exists, and
> the function returns the actual length of the string (excluding the
> terminating NULL-byte).
>
> Signed-off-by: Marek Behún <marek.behun at nic.cz>
> ---
>  board/google/chromebook_coral/coral.c | 13 ++++---------
>  common/board_info.c                   |  2 +-
>  drivers/sysinfo/gpio.c                |  2 +-
>  drivers/sysinfo/rcar3.c               |  2 +-
>  drivers/sysinfo/sandbox.c             |  5 +++--
>  include/sysinfo.h                     | 16 ++++++++++++----
>  lib/smbios.c                          |  2 +-
>  test/dm/sysinfo-gpio.c                | 12 ++++++------
>  test/dm/sysinfo.c                     | 12 ++++++------
>  9 files changed, 35 insertions(+), 31 deletions(-)

So how do we know if the size is too small? The string is silently truncated?

I think -ENOSPC is better?

[..]

Regards,
Simon