lib/utmp.c: Fixed generated strings for "ut_id" #1301
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When no "ut_id" is provided by previous utmp file entry, "login" must generate its own "ut_id". Historically tty number was used for it. However, if current device name is three characters or shorter, then empty "ut_id" is produced or even garbage is copied from uninitialised part of the "line". This commit fixes it. This patch uses unportable C extension Elvis operator as it is already used everywhere in the code. Signed-off-by: Evgeny Grin (Karlson2k) <k2k@drgrin.dev>
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Reviewed-by: Alejandro Colomar <alx@kernel.org>
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When no "ut_id" is provided by previous utmp file entry, "login" must generate its own "ut_id". Historically tty number was used for it. However, if current device name is three characters or shorter, then empty "ut_id" is produced or even garbage is copied from uninitialised part of the "line".
This commit fixes it.
This patch uses unportable C extension Elvis operator as it is already used everywhere in the code.
Extracted from #1293