genhomedircon: avoid use of non-standard `getpwent_r`
The `getpwent_r` function is a non-standard but reentrant version of the
POSIX-defined `getpwent` function. While it should provide the benefit
of being safe to use in multi-threaded environments, it disallows us
from compiling with libc implementations which stick to the POSIX
standard more closely.
As libsemanage may be used in a multi-threaded environment, being
reentrant may in fact be quite important to us. As such, simply
switching out `getpwent_r` against its non-reentrant function can prove
quite dangerous. But interestingly enough, the glibc implementation of
`getpwent_r` does not even guarantee being reentrant. Quoting from
getpwent_r(7):
NOTES
The function getpwent_r() is not really reentrant since it shares
the reading position in the stream with all other threads.
As such, it is non-reentrant in the same sense as its simple `getpwent`
brother and can simply be switched out without losing any guarantees
here.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
1 file changed