From patchwork Mon Jul 10 21:12:25 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Taylor Blau X-Patchwork-Id: 13307666 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A3B51EB64D9 for ; Mon, 10 Jul 2023 21:12:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231983AbjGJVMt (ORCPT ); Mon, 10 Jul 2023 17:12:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37404 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231985AbjGJVMg (ORCPT ); Mon, 10 Jul 2023 17:12:36 -0400 Received: from mail-yb1-xb2a.google.com (mail-yb1-xb2a.google.com [IPv6:2607:f8b0:4864:20::b2a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A7A71E77 for ; Mon, 10 Jul 2023 14:12:27 -0700 (PDT) Received: by mail-yb1-xb2a.google.com with SMTP id 3f1490d57ef6-c1aad78d5b2so8901004276.0 for ; Mon, 10 Jul 2023 14:12:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ttaylorr-com.20221208.gappssmtp.com; s=20221208; t=1689023546; x=1691615546; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=R+z07fKh9BBAq18u3BttAlDWhemyUYrdbgJIH0yVj9k=; b=0Sc9uUG/QUjFpXG1o8bL/5KBqCdeJewvXSi9FVQzafrIaFXTpjFDwaA7ocyXQt3hyG f2CNRpfJpT91ZQRcEOWSo3s2sYrdYouquxASMhqzwn27Fokr5QnrOa72c32/uoWJvlnz yD5YVSXVY2PUb4p8hsbP/89iyN1l8hUHVtzh+U9kVYuQSouYmb2h+ZSaeBUTjPMYUImZ jIABGy89QF4nuie+b4dYQlhiVpEh2mIibBRKvfnxoO0Go9dJsdMPQiilK0jcZI4w46ei N8aTxWN7geiC8V/SyH8pvA3P5NIHznPrygrADWVuZh11qyENfDQrN7o+vc1AXexIZUKK bpuw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1689023546; x=1691615546; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=R+z07fKh9BBAq18u3BttAlDWhemyUYrdbgJIH0yVj9k=; b=lWhTNVEYQECA31CdkDJOf/Q1wcnTKF7x1F06XcfT0sXmQ3LynFdxMUAG7V+dFEl/qS gIEbBjJzTTUh9v9JasxIWOxsZAPyMbBHJbjPpPXGJNK90EuWalLr9l+ywEqJcPSePn35 V5lJ7eUq5Gqu7IonoCZu7vpkkErxK6huCyxA3TMnhmFWDnUqr3He6nLxbNqIbKcmDF37 BT4ujJ6L+RL87NZCS4iRF0GeTBLdM5TtYzTtT/ESc3aysKVnYOfNxkmxmyNGuVvXHXdA HE/6i+JmX8J2dTtTp85dL85nEEGIUoKul/xA1r6UcW2ZzUiKCU2Lm5mop8/rt1b/uo2f F0aw== X-Gm-Message-State: ABy/qLYfH4ZoI5BGj2nr0myf1p2pKQMeM2cNFUTSD0DlTsODVBZ6clcZ kPvZV7x5uxFvFeLEKKHF0XFUmhAi6Ilh1LFZkHov2A== X-Google-Smtp-Source: APBJJlE9suFWBC443GGIxzO7fhbxXPJ33A3EKEpzrKPwd1pzZrX0RTgnqDI++dKjYY7PN6u3j3ARvA== X-Received: by 2002:a0d:df8a:0:b0:577:3225:818d with SMTP id i132-20020a0ddf8a000000b005773225818dmr15407651ywe.11.1689023546621; Mon, 10 Jul 2023 14:12:26 -0700 (PDT) Received: from localhost (104-178-186-189.lightspeed.milwwi.sbcglobal.net. [104.178.186.189]) by smtp.gmail.com with ESMTPSA id j9-20020a816e09000000b0054f50f71834sm180489ywc.124.2023.07.10.14.12.26 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 10 Jul 2023 14:12:26 -0700 (PDT) Date: Mon, 10 Jul 2023 17:12:25 -0400 From: Taylor Blau To: git@vger.kernel.org Cc: Chris Torek , Derrick Stolee , Jeff King , Junio C Hamano , Patrick Steinhardt Subject: [PATCH v5 08/16] refs/packed-backend.c: refactor `find_reference_location()` Message-ID: <25c099a528c87651aeea3dfbd667fb51770dd24a.1689023520.git.me@ttaylorr.com> References: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org The function `find_reference_location()` is used to perform a binary search-like function over the contents of a repository's `$GIT_DIR/packed-refs` file. The search it implements is unlike a standard binary search in that the records it searches over are not of a fixed width, so the comparison must locate the end of a record before comparing it. Extract the core routine of `find_reference_location()` in order to implement a function in the following patch which will find the first location in the `packed-refs` file that *doesn't* match the given pattern. The behavior of `find_reference_location()` is unchanged. Co-authored-by: Jeff King Signed-off-by: Jeff King Signed-off-by: Taylor Blau --- refs/packed-backend.c | 38 ++++++++++++++++++++++---------------- 1 file changed, 22 insertions(+), 16 deletions(-) diff --git a/refs/packed-backend.c b/refs/packed-backend.c index dec15dee31e..e36334e3320 100644 --- a/refs/packed-backend.c +++ b/refs/packed-backend.c @@ -528,22 +528,8 @@ static int load_contents(struct snapshot *snapshot) return 1; } -/* - * Find the place in `snapshot->buf` where the start of the record for - * `refname` starts. If `mustexist` is true and the reference doesn't - * exist, then return NULL. If `mustexist` is false and the reference - * doesn't exist, then return the point where that reference would be - * inserted, or `snapshot->eof` (which might be NULL) if it would be - * inserted at the end of the file. In the latter mode, `refname` - * doesn't have to be a proper reference name; for example, one could - * search for "refs/replace/" to find the start of any replace - * references. - * - * The record is sought using a binary search, so `snapshot->buf` must - * be sorted. - */ -static const char *find_reference_location(struct snapshot *snapshot, - const char *refname, int mustexist) +static const char *find_reference_location_1(struct snapshot *snapshot, + const char *refname, int mustexist) { /* * This is not *quite* a garden-variety binary search, because @@ -589,6 +575,26 @@ static const char *find_reference_location(struct snapshot *snapshot, return lo; } +/* + * Find the place in `snapshot->buf` where the start of the record for + * `refname` starts. If `mustexist` is true and the reference doesn't + * exist, then return NULL. If `mustexist` is false and the reference + * doesn't exist, then return the point where that reference would be + * inserted, or `snapshot->eof` (which might be NULL) if it would be + * inserted at the end of the file. In the latter mode, `refname` + * doesn't have to be a proper reference name; for example, one could + * search for "refs/replace/" to find the start of any replace + * references. + * + * The record is sought using a binary search, so `snapshot->buf` must + * be sorted. + */ +static const char *find_reference_location(struct snapshot *snapshot, + const char *refname, int mustexist) +{ + return find_reference_location_1(snapshot, refname, mustexist); +} + /* * Create a newly-allocated `snapshot` of the `packed-refs` file in * its current state and return it. The return value will already have