On 02/04/20(Thu) 13:36, Philip Guenther wrote:
> On Tue, Mar 31, 2020 at 11:24 PM Martin Pieuchot <m...@openbsd.org> wrote:
>
> > The current form of EV_SET(2) declares a `kevp' variable. This can
> > cause to subtle bugs hard to discover if one uses a variable of the
> > same to retrieve events.
> >
> > Diff below prefixes the locally declared variable by an underscore,
> > like it it done in FD_ZERO(), which should be good enough to prevent
> > surprises.
> >
> > Is it the right way to correct such issue? How many underscores are
> > enough? Can the standards gurus tell me?
> >
>
> tl;dr: this should use a variable that starts with either two underbars
> (__kevp) or an underbar and a capital (_Kevp). The same is true of
> FD_ZERO().
> [...]
Thanks, here it is, ok?
Index: sys/event.h
===================================================================
RCS file: /cvs/src/sys/sys/event.h,v
retrieving revision 1.33
diff -u -p -r1.33 event.h
--- sys/event.h 20 Feb 2020 16:56:52 -0000 1.33
+++ sys/event.h 3 Apr 2020 07:47:17 -0000
@@ -42,14 +42,14 @@
#define EVFILT_SYSCOUNT 8
-#define EV_SET(kevp_, a, b, c, d, e, f) do { \
- struct kevent *kevp = (kevp_); \
- (kevp)->ident = (a); \
- (kevp)->filter = (b); \
- (kevp)->flags = (c); \
- (kevp)->fflags = (d); \
- (kevp)->data = (e); \
- (kevp)->udata = (f); \
+#define EV_SET(kevp, a, b, c, d, e, f) do { \
+ struct kevent *__kevp = (kevp); \
+ (__kevp)->ident = (a); \
+ (__kevp)->filter = (b); \
+ (__kevp)->flags = (c); \
+ (__kevp)->fflags = (d); \
+ (__kevp)->data = (e); \
+ (__kevp)->udata = (f); \
} while(0)
struct kevent {
Index: sys/select.h
===================================================================
RCS file: /cvs/src/sys/sys/select.h,v
retrieving revision 1.17
diff -u -p -r1.17 select.h
--- sys/select.h 12 Sep 2016 19:41:20 -0000 1.17
+++ sys/select.h 3 Apr 2020 07:48:31 -0000
@@ -100,11 +100,11 @@ __fd_isset(int fd, const fd_set *p)
#define FD_COPY(f, t) (void)(*(t) = *(f))
#endif
#define FD_ZERO(p) do { \
- fd_set *_p = (p); \
- __size_t _n = __howmany(FD_SETSIZE, __NFDBITS); \
+ fd_set *__p = (p); \
+ __size_t __n = __howmany(FD_SETSIZE, __NFDBITS); \
\
- while (_n > 0) \
- _p->fds_bits[--_n] = 0; \
+ while (__n > 0) \
+ __p->fds_bits[--__n] = 0; \
} while (0)
#if __BSD_VISIBLE
