Re: cluts review

[Solar Designer <solar@openwall.com>]

On Wed, Jul 13, 2011 at 10:26:03AM -0400, Rich Felker wrote:
> cat <<EOF >test.c
> #define _XOPEN_SOURCE 700
> #include <limits.h>
> PATH_MAX
> EOF
> gcc -E test.c | tail -n 1

Yeah, it works for me too.  It's just that in cluts.c, after all those
other #include's and with no feature test macros defined at all,
<limits.h> wouldn't provide PATH_MAX.  Somehow <limits.h> on its
own, also with no feature test macros at all, does provide PATH_MAX.
Anyhow, I am not going to investigate further.  It is clear that when we
do request at least _BSD_SOURCE or _XOPEN_SOURCE, then <limits.h> does
give us PATH_MAX.

> > > > -    act.sa_flags   = SA_NODEFER;
> > > > +    act.sa_flags   = 0;
> > > 
> > > This was being used as part of the longjmp trick.
> > 
> > Why, how?  Did we seriously want to keep the signal blocked?
> 
> It's to leave the signal unblocked so that longjmp can return without
> having to restore the signal mask.

Oh, you're right, and my comment above re: "keep the signal blocked"
didn't make sense (it's the other way around).

> It might be slightly more portable
> to just manually unblock it or use sigsetjmp/siglongjmp to do so, but
> unless I'm mistaken the last system with broken SA_NODEFER was Linux
> 1.3 or so...

I think that we need to switch to using sigsetjmp/siglongjmp as I had
suggested before.

Alexander