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Date: Thu, 20 May 2004 23:10:58 +0200
From: Pawel Jakub Dawidek <pjd@FreeBSD.org>
To: Andre Oppermann <andre@freebsd.org>
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On Thu, May 20, 2004 at 11:01:46PM +0200, Andre Oppermann wrote:
+> Pawel Jakub Dawidek wrote:
+> >=20
+> > Hello.
+> >=20
+> > In in_pcblookup_hash() function, in the last loop if we find exact
+> > match, we return immediately, if it is "wild", we store a pointer and
+> > we countinue looking for exact match.
+> > I wonder if this is ok, that we change pointer every time we find a
+> > "wild" match. Is it inteded? Shouldn't it be:
+> >=20
+> >         http://people.freebsd.org/~pjd/patches/in_pcb.c.2.patch
+>=20
+> No.  This is a stack variable which is unconditionally initialized to
+> NULL a few lines earlier.  Checking for variable =3D=3D NULL is always
+> going to be true and makes your 'optimization' just redundand.

But we have loop there:

	local_wild =3D NULL;
	[...]
	LIST_FOREACH(...) {
		[...]
		local_wild =3D <something>;
		[...]
	}

Isn't that possible that local_wild will be set few times?

+> > While I'm here, I want to improve code readability a bit:
+> >=20
+> >         http://people.freebsd.org/~pjd/patches/in_pcb.c.3.patch
+> >=20
+> > Is it ok?
+>=20
+> No.  You change the logic of the 'if' statements to something totally
+> different.  This ain't going to work in any way.

Hmm, no:

for (...) {
	if (a =3D=3D b && c =3D=3D d) {
		/* do something */
	}
	/* nothing here */
}

is equivalent to:

for (...) {
	if (a !=3D b || c !=3D d)
		continue;
	/* do something */
}

isn't it?

--=20
Pawel Jakub Dawidek                       http://www.FreeBSD.org
pjd@FreeBSD.org                           http://garage.freebsd.pl
FreeBSD committer                         Am I Evil? Yes, I Am!

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