From patchwork Thu Sep 20 18:04:11 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Taylor Blau X-Patchwork-Id: 10608431 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 516FC913 for ; Thu, 20 Sep 2018 18:04:17 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 488A22E5C7 for ; Thu, 20 Sep 2018 18:04:17 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 3CC942E5CA; Thu, 20 Sep 2018 18:04:17 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 2895E2E5C7 for ; Thu, 20 Sep 2018 18:04:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387922AbeITXsz (ORCPT ); Thu, 20 Sep 2018 19:48:55 -0400 Received: from mail-io1-f67.google.com ([209.85.166.67]:43688 "EHLO mail-io1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732340AbeITXsz (ORCPT ); Thu, 20 Sep 2018 19:48:55 -0400 Received: by mail-io1-f67.google.com with SMTP id y10-v6so8661943ioa.10 for ; Thu, 20 Sep 2018 11:04:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=github.com; s=google; h=from:date:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=VoFL34O/3WN167HWDTZOjJ7Q5jnYm70lYMA2ykoccJ4=; b=UnJSan6/rBz0TwWMrj808HHf9ZgQIlejMem+AadcOd3gwU7M/QPAchXp1ot1O002rt K0qn9HJNFUUzbUcJXGZPFSKGqPKTk+9Ov1jWaq5VfoecMLdV5nL2Wq3Qtly24zIgjYQ7 MB+/RrxNV1G1f7oOpIg5OiZrTsiHkb9J/rLng= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:date:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=VoFL34O/3WN167HWDTZOjJ7Q5jnYm70lYMA2ykoccJ4=; b=eU5t06aiFAUPfAJ+X6zzU/CdSTpWST6Rjc68aJaSjzits1hOx/fu6AiCDRpLqgV92O 26tO1pKhxWx3o7VMU9r6LLWCdKewH2gAlE76Vu31GDjTHDl6okeCX8fRlASym0M/mgpk L35cT5j+Se9QDWM3GVlAJq2VoqlPihanNoBHAZieEYf8Gp2kCirdcCcK3SXEqCvBulSM NCexRlXZUrfpDuiUvdVY/ixhwVLfYn0eHcTBZpTRJHB12TQA5WVGKchD7D+uecibrziG p3tsab8WV/Lc0+1Fnv0Eiv7rDNe1q9aUX4hYBsf0vebxU0zq7jLIYucEDPGjE8Jzk4dX v/WA== X-Gm-Message-State: APzg51ArO247zanQNG9FDi88179TONOQsoujRruhZ1FHfTzY9Ol5rAcX 5xnj7/sC7VIBrWA+jXY2FqSqrg42DrHpcHfLrKa+O8GV3uP9SdonG0EonZD102yMKcwGBpsyddN 1R5C2nTCvXnhBwhZ5NfzEC5Hh1POXbxnu4sUxtkGSadtGLz+bQwkKonjJYUmLCQ== X-Google-Smtp-Source: ANB0VdZI81F4Xso7YQsBdA/fxpbsqVeP09hvgHOyYYhTuraI5owuQyu5WSf7g/C7B0KyJ62wryMpaw== X-Received: by 2002:a24:198c:: with SMTP id b134-v6mr73019itb.125.1537466653159; Thu, 20 Sep 2018 11:04:13 -0700 (PDT) Received: from localhost ([173.225.52.219]) by smtp.gmail.com with ESMTPSA id y25-v6sm922785ita.3.2018.09.20.11.04.11 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 20 Sep 2018 11:04:12 -0700 (PDT) From: Taylor Blau X-Google-Original-From: Taylor Blau Date: Thu, 20 Sep 2018 14:04:11 -0400 To: git@vger.kernel.org Cc: peff@peff.net Subject: [PATCH 2/3] transport.c: introduce core.alternateRefsCommand Message-ID: <4c4900722cab253b3ce33cb28910c4602ce44536.1537466087.git.me@ttaylorr.com> References: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.9.5 (2018-04-13) Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP When in a repository containing one or more alternates, Git would sometimes like to list references from its alternates. For example, 'git receive-pack' list the objects pointed to by alternate references as special ".have" references. Listing ".have" references is designed to make pushing changes from upstream to a fork a lightweight operation, by advertising to the pusher that the fork already has the objects (via its alternate). Thus, the client can avoid sending them. However, when the alternate has a pathologically large number of references, the initial advertisement is too expensive. In fact, it can dominate any such optimization where the pusher avoids sending certain objects. Introduce "core.alternateRefsCommand" in order to provide a facility to limit or filter alternate references. This can be used, for example, to filter out "uninteresting" references from the initial advertisement in the above scenario. Let the repository that has alternates configure this command to avoid trusting the alternate to provide us a safe command to run in the shell. To behave differently on each alternate (e.g., only list tags from alternate A, only heads from B) provide the path of the alternate as the first argument. Signed-off-by: Taylor Blau --- Documentation/config.txt | 6 +++++ t/t5410-receive-pack.sh | 47 ++++++++++++++++++++++++++++++++++++++++ transport.c | 19 ++++++++++++---- 3 files changed, 68 insertions(+), 4 deletions(-) create mode 100755 t/t5410-receive-pack.sh diff --git a/Documentation/config.txt b/Documentation/config.txt index 112041f407..b908bc5825 100644 --- a/Documentation/config.txt +++ b/Documentation/config.txt @@ -616,6 +616,12 @@ core.preferSymlinkRefs:: This is sometimes needed to work with old scripts that expect HEAD to be a symbolic link. +core.alternateRefsCommand:: + When listing references from an alternate (e.g., in the case of ".have"), use + the shell to execute the specified command instead of + linkgit:git-for-each-ref[1]. The first argument is the path of the alternate. + Output must be of the form: `%(objectname) SPC %(refname)`. + core.bare:: If true this repository is assumed to be 'bare' and has no working directory associated with it. If this is the case a diff --git a/t/t5410-receive-pack.sh b/t/t5410-receive-pack.sh new file mode 100755 index 0000000000..09fb3f39a1 --- /dev/null +++ b/t/t5410-receive-pack.sh @@ -0,0 +1,47 @@ +#!/bin/sh + +test_description='git receive-pack test' + +. ./test-lib.sh + +test_expect_success 'setup' ' + test_commit one && + git update-ref refs/heads/a HEAD && + test_commit two && + git update-ref refs/heads/b HEAD && + test_commit three && + git update-ref refs/heads/c HEAD && + git clone --bare . fork && + git clone fork pusher && + ( + cd fork && + git config receive.advertisealternates true && + git update-ref -d refs/heads/a && + git update-ref -d refs/heads/b && + git update-ref -d refs/heads/c && + git update-ref -d refs/heads/master && + git update-ref -d refs/tags/one && + git update-ref -d refs/tags/two && + git update-ref -d refs/tags/three && + printf "../../.git/objects" >objects/info/alternates + ) +' + +extract_haves () { + depacketize - | grep -o '^.* \.have' +} + +test_expect_success 'with core.alternateRefsCommand' ' + test_config -C fork core.alternateRefsCommand \ + "git --git-dir=\"\$1\" for-each-ref \ + --format=\"%(objectname) %(refname)\" \ + refs/heads/a refs/heads/c;:" && + cat >expect <<-EOF && + $(git rev-parse a) .have + $(git rev-parse c) .have + EOF + printf "0000" | git receive-pack fork | extract_haves >actual && + test_cmp expect actual +' + +test_done diff --git a/transport.c b/transport.c index 24ae3f375d..e7d2cdf00b 100644 --- a/transport.c +++ b/transport.c @@ -1328,10 +1328,21 @@ char *transport_anonymize_url(const char *url) static void fill_alternate_refs_command(struct child_process *cmd, const char *repo_path) { - cmd->git_cmd = 1; - argv_array_pushf(&cmd->args, "--git-dir=%s", repo_path); - argv_array_push(&cmd->args, "for-each-ref"); - argv_array_push(&cmd->args, "--format=%(objectname) %(refname)"); + const char *value; + + if (!git_config_get_value("core.alternateRefsCommand", &value)) { + cmd->use_shell = 1; + + argv_array_push(&cmd->args, value); + argv_array_push(&cmd->args, repo_path); + } else { + cmd->git_cmd = 1; + + argv_array_pushf(&cmd->args, "--git-dir=%s", repo_path); + argv_array_push(&cmd->args, "for-each-ref"); + argv_array_push(&cmd->args, "--format=%(objectname) %(refname)"); + } + cmd->env = local_repo_env; cmd->out = -1; }