From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pierre Habouzit Subject: Re: [PATCH 3/3] pretty=format: Avoid some expensive calculations when not needed Date: Wed, 07 Nov 2007 01:14:58 +0100 Message-ID: <20071107001458.GE4382@artemis.corp> References: <7v8x5cqxn0.fsf@gitster.siamese.dyndns.org> <472F7B2F.4050608@lsrfire.ath.cx> <7vejf4kwry.fsf@gitster.siamese.dyndns.org> <4730EB4E.4080903@lsrfire.ath.cx> <4730F5FA.3030705@lsrfire.ath.cx> <20071107001112.GD4382@artemis.corp> Mime-Version: 1.0 Content-Type: multipart/signed; boundary="d8Lz2Tf5e5STOWUP"; protocol="application/pgp-signature"; micalg=SHA1 To: =?utf-8?B?UmVuw6k=?= Scharfe , Junio C Hamano , Johannes Schindelin , git@vger.kernel.org X-From: git-owner@vger.kernel.org Wed Nov 07 01:15:17 2007 Return-path: Envelope-to: gcvg-git-2@gmane.org Received: from vger.kernel.org ([209.132.176.167]) by lo.gmane.org with esmtp (Exim 4.50) id 1IpYZg-0001SH-NZ for gcvg-git-2@gmane.org; Wed, 07 Nov 2007 01:15:17 +0100 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754199AbXKGAPA (ORCPT ); Tue, 6 Nov 2007 19:15:00 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754196AbXKGAPA (ORCPT ); Tue, 6 Nov 2007 19:15:00 -0500 Received: from pan.madism.org ([88.191.52.104]:56994 "EHLO hermes.madism.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754076AbXKGAO7 (ORCPT ); Tue, 6 Nov 2007 19:14:59 -0500 Received: from madism.org (olympe.madism.org [82.243.245.108]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "artemis.madism.org", Issuer "madism.org" (not verified)) by hermes.madism.org (Postfix) with ESMTP id C286E28D35; Wed, 7 Nov 2007 01:14:58 +0100 (CET) Received: by madism.org (Postfix, from userid 1000) id 6DF15352263; Wed, 7 Nov 2007 01:14:58 +0100 (CET) Mail-Followup-To: Pierre Habouzit , =?utf-8?B?UmVuw6k=?= Scharfe , Junio C Hamano , Johannes Schindelin , git@vger.kernel.org Content-Disposition: inline In-Reply-To: <20071107001112.GD4382@artemis.corp> X-Face: $(^e[V4D-[`f2EmMGz@fgWK!e.B~2g.{08lKPU(nc1J~z\4B>*JEVq:E]7G-\6$Ycr4<;Z!|VY6Grt]+RsS$IMV)f>2)M="tY:ZPcU;&%it2D81X^kNya0=L]"vZmLP+UmKhgq+u*\.dJ8G!N&=EvlD User-Agent: Madmutt/devel (Linux) Sender: git-owner@vger.kernel.org Precedence: bulk X-Mailing-List: git@vger.kernel.org Archived-At: --d8Lz2Tf5e5STOWUP Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, Nov 07, 2007 at 12:11:12AM +0000, Pierre Habouzit wrote: > On Tue, Nov 06, 2007 at 11:17:14PM +0000, Ren=C3=A9 Scharfe wrote: > > I haven't seen any comments on strbuf_expand. Is it too far out? > > Here it is again, adjusted for current master and with the changes > > to strbuf.[ch] coming first: >=20 > I have one. >=20 > > strbuf.c | 22 +++++ > > strbuf.h | 3=20 > > pretty.c | 276 ++++++++++++++++++++++++++++++++++--------------------= --------- > > 3 files changed, 178 insertions(+), 123 deletions(-) > >=20 > > diff --git a/strbuf.c b/strbuf.c > > index f4201e1..b71da99 100644 > > --- a/strbuf.c > > +++ b/strbuf.c > > @@ -129,6 +129,28 @@ void strbuf_addf(struct strbuf *sb, const char *fm= t, ...) > > strbuf_setlen(sb, sb->len + len); > > } > > =20 > > +void strbuf_expand(struct strbuf *sb, const char *fmt, > > + const char **placeholders, expand_fn_t fn, void *co= ntext) > > +{ > > + char c; > > + const char **p; > > + > > + while ((c =3D *fmt++)) { > > + if (c !=3D '%') { > > + strbuf_addch(sb, c); > > + continue; > > + } >=20 > strbuf_addch is pretty inneficient as it puts NULs each time. rather > do that (sketchy) : >=20 > { > for (;;) { > const char *percent =3D strchr(fmt, '%'); > if (!percent) > break; > strbuf_add(sb, fmt, percent - fmt); > fmt =3D percent + 1; >=20 > /* do your stuff */ > } > strbuf_addstr(sb, fmt); > } Or if we are at this level of micro-optimization: { const char *percent =3D strchrnul(fmt, '%'); while (*percent) { strbuf_add(sb, fmt, percent - fmt); fmt =3D percent + 1; /* do your stuff */ percent =3D strchrnul(fmt, '%'); } strbuf_add(sb, fmt, percent - fmt); } Which would require strchrnul, but it's trivial compat/ material for sure. --=20 =C2=B7O=C2=B7 Pierre Habouzit =C2=B7=C2=B7O madcoder@debia= n.org OOO http://www.madism.org --d8Lz2Tf5e5STOWUP Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.6 (GNU/Linux) iD8DBQBHMQOCvGr7W6HudhwRAtc4AJ95JFmBLIOokUe8XvPajkYaTrnBUACdGSIQ SWkESm+carb1MKbNbWA5NiI= =yhJI -----END PGP SIGNATURE----- --d8Lz2Tf5e5STOWUP--