On 2023-01-10 14:28, Alejandro Colomar wrote:
On 1/10/23 17:54, Mathieu Desnoyers wrote:
[...]
.BI "int syscall(SYS_rseq, struct rseq *_Nullable " rseq ", uint32_t
" rseq_len \
What's the meaning for NULL? Does it have a valid sentinel meaning,
or is it an invalid address? If it's just interpreted as an invalid
address (for which from a user-space perspective a crash would be
legitimate), then I'd remove _Nullable.
With the flags that are currently implemented (0 or
RSEQ_FLAG_UNREGISTER),
the rseq argument is not expected to be legitimately NULL (it would
return
-1, errno=EFAULT on registration, or -1, errno=EINVAL on unregister
attempt).
We may add new flags in the future which would not care about the rseq
address
(it could very well be null then). Do you recommend that we only add the
_Nullable tag when this occurs ?
Yes; since it's what the user can pass, it makes sense to be as
constrained as possible. If it were some return that the user would
have to inspect, it would make sense to be cautious on the NULL side of
things an use _Nullable preventively, but for an input, non-null is
preferred for now.
OK, updated.
[...]
Updated version based on your comments pushed into my repo, thanks!
Cool! I'll have a look.
Thanks! Once you find it to your liking, I plan to sent it as a patch
against the man-pages project.
Mathieu
Cheers,
Alex
Mathieu
--
Mathieu Desnoyers
EfficiOS Inc.
https://www.efficios.com
