From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.org/gmane.linux.lib.musl.general/10064 Path: news.gmane.org!not-for-mail From: Rich Felker Newsgroups: gmane.linux.lib.musl.general Subject: Re: [PATCH 2/2] refactor name_from_dns Date: Fri, 27 May 2016 00:40:57 -0400 Message-ID: <20160527044057.GB10893@brightrain.aerifal.cx> References: <1464168134-17039-1-git-send-email-ncopa@alpinelinux.org> <1464168134-17039-2-git-send-email-ncopa@alpinelinux.org> Reply-To: musl@lists.openwall.com NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: ger.gmane.org 1464324077 30051 80.91.229.3 (27 May 2016 04:41:17 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Fri, 27 May 2016 04:41:17 +0000 (UTC) To: musl@lists.openwall.com Original-X-From: musl-return-10077-gllmg-musl=m.gmane.org@lists.openwall.com Fri May 27 06:41:16 2016 Return-path: Envelope-to: gllmg-musl@m.gmane.org Original-Received: from mother.openwall.net ([195.42.179.200]) by plane.gmane.org with smtp (Exim 4.69) (envelope-from ) id 1b69aF-000648-UK for gllmg-musl@m.gmane.org; Fri, 27 May 2016 06:41:16 +0200 Original-Received: (qmail 18100 invoked by uid 550); 27 May 2016 04:41:11 -0000 Mailing-List: contact musl-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Original-Received: (qmail 18076 invoked from network); 27 May 2016 04:41:10 -0000 Content-Disposition: inline In-Reply-To: <1464168134-17039-2-git-send-email-ncopa@alpinelinux.org> User-Agent: Mutt/1.5.21 (2010-09-15) Original-Sender: Rich Felker Xref: news.gmane.org gmane.linux.lib.musl.general:10064 Archived-At: On Wed, May 25, 2016 at 11:22:14AM +0200, Natanael Copa wrote: > loop over an address family / resource record mapping to avoid > repetitive code. > --- > src/network/lookup_name.c | 27 +++++++++++++-------------- > 1 file changed, 13 insertions(+), 14 deletions(-) > > diff --git a/src/network/lookup_name.c b/src/network/lookup_name.c > index d3d97b4..99364ab 100644 > --- a/src/network/lookup_name.c > +++ b/src/network/lookup_name.c > @@ -141,20 +141,19 @@ static int name_from_dns(struct address buf[static MAXADDRS], char canon[static > int qlens[2], alens[2]; > int i, nq = 0; > struct dpc_ctx ctx = { .addrs = buf, .canon = canon }; > - > - if (family != AF_INET6) { > - qlens[nq] = __res_mkquery(0, name, 1, RR_A, 0, 0, 0, > - qbuf[nq], sizeof *qbuf); > - if (qlens[nq] == -1) > - return EAI_NONAME; > - nq++; > - } > - if (family != AF_INET) { > - qlens[nq] = __res_mkquery(0, name, 1, RR_AAAA, 0, 0, 0, > - qbuf[nq], sizeof *qbuf); > - if (qlens[nq] == -1) > - return EAI_NONAME; > - nq++; > + struct { int af; int rr; } afrr[2] = { > + { .af = AF_INET6, .rr = RR_A }, > + { .af = AF_INET, .rr = RR_AAAA }, > + }; > + > + for (i=0; i<2; i++) { > + if (family != afrr[i].af) { > + qlens[nq] = __res_mkquery(0, name, 1, afrr[i].rr, > + 0, 0, 0, qbuf[nq], sizeof *qbuf); > + if (qlens[nq] == -1) > + return EAI_NONAME; > + nq++; > + } Can you compare the codegen for this as written vs making the table static-const? I wonder which gcc does better with. My guess would be static-const is better if it actually emits the table and loops over it, but auto storage like you did might be better if that helps it just unroll it plugging in the values. Rich