time_t isn't necessarily unsigned (in fact, it's likely to be signed.
Therefore, parse the number as the right type, via a2i(time_t, ...).
Still, reject negative numbers, just to be cautious. It was done
before (strtoull_noneg()), so it shouldn't be a problem. (However,
strtoull_noneg() was only introduced recently, and before that we called
strtoull(3), which silently accepted negative values.)
Remove the limitation of ULONG_MAX, which seems arbitrary. It probably
was written in times where 'time_t' had the same length of 'long', and
this was thus a test that the value didn't overflow 'time_t'. Such a
test is implicit in the a2i() call, so forget about it.
Unify the error messages into a single one that provides all the info
(except the value of 'fallback').
Link: <cb610d54b4 (r136407772)>
Reviewed-by: Iker Pedrosa <ipedrosa@redhat.com>
Cc: Chris Lamb <lamby@debian.org>
Cc: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Alejandro Colomar <alx@kernel.org>
'endptr' is appropriate internally in strtol(3) because it's a pointer
to 'end', and 'end' itself is a pointer to one-after-the-last character
of the numeric string. In other words,
endptr == &end
However, naming the pointer whose address we pass to strtol(3)'s
'endptr' feels wrong, and causes me trouble while parsing the code; I
need to double check the number of dereferences, because something feels
wrong in my head.
Signed-off-by: Alejandro Colomar <alx@kernel.org>
strtou[l]l(3) silently converts negative numbers into positive. This
behavior is wrong: a negative value should be parsed as a negative
value, which would underflow unsigned (long) long, and so would return
the smallest possible value, 0, and set errno to ERANGE to report an
error.
Reviewed-by: Iker Pedrosa <ipedrosa@redhat.com>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Signed-off-by: Alejandro Colomar <alx@kernel.org>
- Set errno = 0 before the call. Otherwise, it may contain anything.
- ERANGE is not the only possible errno value of these functions. They
can also set it to EINVAL.
- Any errno value after these calls is bad; just compare against 0.
- Don't check for the return value; just errno. This function is
guaranteed to not modify errno on success (POSIX).
- Check endptr == str, which may or may not set EINVAL.
Suggested-by: Iker Pedrosa <ipedrosa@redhat.com>
Signed-off-by: Alejandro Colomar <alx@kernel.org>
