From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ramkumar Ramachandra Subject: [PATCH 3/5] sha1_name.c: simplify @-parsing in get_sha1_basic() Date: Wed, 1 May 2013 21:50:33 +0530 Message-ID: <1367425235-14998-4-git-send-email-artagnon@gmail.com> References: <1367425235-14998-1-git-send-email-artagnon@gmail.com> Cc: Junio C Hamano , Felipe Contreras , Jeff King , Duy Nguyen To: Git List X-From: git-owner@vger.kernel.org Wed May 01 18:20:40 2013 Return-path: Envelope-to: gcvg-git-2@plane.gmane.org Received: from vger.kernel.org ([209.132.180.67]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1UXZlm-0006UK-96 for gcvg-git-2@plane.gmane.org; Wed, 01 May 2013 18:20:38 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758711Ab3EAQUe (ORCPT ); Wed, 1 May 2013 12:20:34 -0400 Received: from mail-pa0-f49.google.com ([209.85.220.49]:57806 "EHLO mail-pa0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754558Ab3EAQUc (ORCPT ); Wed, 1 May 2013 12:20:32 -0400 Received: by mail-pa0-f49.google.com with SMTP id hk2so939097pac.36 for ; Wed, 01 May 2013 09:20:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=x-received:from:to:cc:subject:date:message-id:x-mailer:in-reply-to :references; bh=+Y9EdjhrHtokTrXgJNG18o9buT7weheAz3affX3SmB0=; b=d1DHdJEGttWYCYXNqFG/USVeARjVl5URJgjGqvK9+GaVWKJ4Z2YzBxRUhZ7MI9iOAH hhNOM2SOc9abUZbtGPqbK/Fwz/EUg+LvQ+2QCooykqADuZrXNIOu9FOXm46gV2siKHIE iUdY0Mc/ZaVUtszG6690wOn0TcveAltYgfZcl7PGkEnAH/rz7QjjAQ/MKiGEuwkX35Qb G3DFFu0O66fJfrjCYJNsXSFys+1EjVsAmtCrp4VKdKjDwzPgFuLJZm7wkuSoQDHhFSZC UpUZHYONAJdG+rb6hl/ZnSIXeoSjGj23nXQY3BmC5+Mat4OGjgMY8tzS0czo+I49eiuL uAiA== X-Received: by 10.68.135.133 with SMTP id ps5mr4761419pbb.158.1367425231880; Wed, 01 May 2013 09:20:31 -0700 (PDT) Received: from localhost.localdomain ([122.164.132.210]) by mx.google.com with ESMTPSA id sg4sm3549741pbc.7.2013.05.01.09.20.29 for (version=TLSv1.2 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Wed, 01 May 2013 09:20:31 -0700 (PDT) X-Mailer: git-send-email 1.8.3.rc0.24.g6456091 In-Reply-To: <1367425235-14998-1-git-send-email-artagnon@gmail.com> Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: Presently, the logic for @-parsing is horribly convoluted. Prove that it is very straightforward by laying out the three cases (@{N}, @{u[upstream], and @{-N}) and explaining how each case should be handled in comments. All tests pass, and no functional changes have been introduced. Signed-off-by: Ramkumar Ramachandra --- sha1_name.c | 65 ++++++++++++++++++++++++++++++++++++++++++------------------- 1 file changed, 45 insertions(+), 20 deletions(-) diff --git a/sha1_name.c b/sha1_name.c index be1d12c..f30e344 100644 --- a/sha1_name.c +++ b/sha1_name.c @@ -463,9 +463,26 @@ static int get_sha1_basic(const char *str, int len, unsigned char *sha1) */ for (at = len - 4; at >= 0; at--) { if (str[at] == '@' && str[at+1] == '{') { + /* Set reflog_len only if we + * don't see a @{u[pstream]}. The + * @{N} and @{-N} forms have to do + * with reflog digging. + */ + + /* Setting len to at means that we are + * only going to process the part + * before the @ until we reach "if + * (reflog)" at the end of the + * function. That is only applicable + * in the @{N} case; in the @{-N} and + * @{u[pstream]} cases, we will run it + * through interpret_branch_name(). + */ + if (!upstream_mark(str + at, len - at)) { reflog_len = (len-1) - (at+2); - len = at; + if (str[at + 2] != '-') + len = at; } break; } @@ -476,22 +493,34 @@ static int get_sha1_basic(const char *str, int len, unsigned char *sha1) if (len && ambiguous_path(str, len)) return -1; - if (!len && reflog_len) { - struct strbuf buf = STRBUF_INIT; - int ret; - /* try the @{-N} syntax for n-th checkout */ - ret = interpret_branch_name(str+at, &buf); - if (ret > 0) { - /* substitute this branch name and restart */ - return get_sha1_1(buf.buf, buf.len, sha1, 0); - } else if (ret == 0) { - return -1; + if (reflog_len) { + if (!len) + /* In the @{N} case where there's nothing + * before the @. + */ + refs_found = dwim_log("HEAD", 4, sha1, &real_ref); + else { + /* The @{N} case where there is something + * before the @ for dwim_log to figure out, + * and the @{-N} case. + */ + refs_found = dwim_log(str, len, sha1, &real_ref); + + if (!refs_found && str[2] == '-') { + /* The @{-N} case that resolves to a + * detached HEAD (ie. not a ref) + */ + struct strbuf buf = STRBUF_INIT; + if (interpret_branch_name(str, &buf) > 0) { + get_sha1_hex(buf.buf, sha1); + refs_found = 1; + reflog_len = 0; + } + strbuf_release(&buf); + } } - /* allow "@{...}" to mean the current branch reflog */ - refs_found = dwim_ref("HEAD", 4, sha1, &real_ref); - } else if (reflog_len) - refs_found = dwim_log(str, len, sha1, &real_ref); - else + } else + /* The @{u[pstream]} case */ refs_found = dwim_ref(str, len, sha1, &real_ref); if (!refs_found) @@ -506,10 +535,6 @@ static int get_sha1_basic(const char *str, int len, unsigned char *sha1) unsigned long co_time; int co_tz, co_cnt; - /* a @{-N} placed anywhere except the start is an error */ - if (str[at+2] == '-') - return -1; - /* Is it asking for N-th entry, or approxidate? */ for (i = nth = 0; 0 <= nth && i < reflog_len; i++) { char ch = str[at+2+i]; -- 1.8.3.rc0.24.g6456091