From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS53758 23.128.96.0/24 X-Spam-Status: No, score=-3.8 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI, SPF_HELO_PASS,SPF_PASS shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by dcvr.yhbt.net (Postfix) with ESMTP id DF4031F953 for ; Fri, 12 Nov 2021 17:43:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235526AbhKLRpr (ORCPT ); Fri, 12 Nov 2021 12:45:47 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57770 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235122AbhKLRpq (ORCPT ); Fri, 12 Nov 2021 12:45:46 -0500 Received: from mail-wm1-x32c.google.com (mail-wm1-x32c.google.com [IPv6:2a00:1450:4864:20::32c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A3DE3C061766 for ; Fri, 12 Nov 2021 09:42:55 -0800 (PST) Received: by mail-wm1-x32c.google.com with SMTP id i12so7541737wmq.4 for ; Fri, 12 Nov 2021 09:42:55 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=message-id:from:date:subject:fcc:content-transfer-encoding :mime-version:to:cc; bh=FkpMp3XYrq21/NEPmpEAlIjHhQqqMQ5OFa9N7TXBFG8=; b=oQl25kN8rTFcyQ+zH4SQJ89qPPaDgH+h8QIX8injp9iInAngCYqZMQ8/05Mq0T8Ihd Tam4+OJJkwvlLx8rvemf4nMhj4Oq9Wygy1fJ53goPdx21dQaqp3EYXXQeV+nQxSTmeS6 CrheSBS7ahdsbf7A+YTezCaxjWo8Tj0XpnuaUxLApOjfcIr63/ouQMsEontEX6Nlw3+d aUGKfMctoRp5G3985RihXRHEmoMtVdOjWcNgYB/dnPYVuSECBhwUT0pgfyNU5p1wl/Oq O7dJ939xVJTzrZqTu7KARCUnK3rDC8m76xxWNdd68T7iB21L+y50SZSgcBrhABBykfGc ZR8A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:from:date:subject:fcc :content-transfer-encoding:mime-version:to:cc; bh=FkpMp3XYrq21/NEPmpEAlIjHhQqqMQ5OFa9N7TXBFG8=; b=nQs368QZysd5LIhOy9dSqsf+3sH9zZEr9NEmoCXHU+ndhg79JJturh9zOve3D7FrTN mM+G0MEa+le0lL9GluX/G+k7/XGgPfToq18pvpYwQz2/CnqafGiM4GQ+a88Fkf4vxUYm SkahEflOybts8b2CA0HhQw8FKbmeyxyWKSJd/MFQyKB1VDEnkVq0PgLTJ4wrssUa0lgT oROQs19exg0SWUmkofyP1OQvxp4NC6NhWbOKBGj2cts8EO5Hk+AMTHpyQvnTYQTCvzRD zHFjWudFTr8FERHF2hGXYXf85nUBSenoQ11wtn8kTUpbmnOAyvUoJmZtIdVyN04P0Md/ mJ/g== X-Gm-Message-State: AOAM532+8DX2SoYxKaBb0fsFax9AALu6KDfkVCVG7n0QxuoD74nWK2us /h9LZ8CFq65SXPCBbd4UTJ5BfiXQ4/k= X-Google-Smtp-Source: ABdhPJydpAHfHr0ZedZmQKpmv7AjtSQeSRqbGz+TmHV0jL46VTk+RqedSaCdUUIEDZ6UNf+W59U1wg== X-Received: by 2002:a7b:c8ca:: with SMTP id f10mr36271871wml.6.1636738974034; Fri, 12 Nov 2021 09:42:54 -0800 (PST) Received: from [127.0.0.1] ([13.74.141.28]) by smtp.gmail.com with ESMTPSA id w17sm6532740wrp.79.2021.11.12.09.42.53 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 12 Nov 2021 09:42:53 -0800 (PST) Message-Id: From: "Elijah Newren via GitGitGadget" Date: Fri, 12 Nov 2021 17:42:52 +0000 Subject: [PATCH] sequencer: fix environment that 'exec' commands run under Fcc: Sent Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit MIME-Version: 1.0 To: git@vger.kernel.org Cc: Elijah Newren , Elijah Newren Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org From: Elijah Newren Commands executed from `git rebase --exec` can give different behavior from within that environment than they would outside of it, due to the fact that sequencer.c exports both GIT_DIR and GIT_WORK_TREE. For example, if the relevant script calls something like git -C ../otherdir log --format=%H --no-walk the user may be surprised to find that the command above does not show a commit hash from ../otherdir, because $GIT_DIR prevents automatic gitdir detection and makes the -C option useless. This is a regression in behavior from the original legacy implemented-in-shell rebase. It is perhaps rare for it to cause problems in practice, especially since most small problems that were caused by this area of bugs has been fixed-up in the past in a way that masked the particular bug observed without fixing the real underlying problem. How we arrived at the current situation is perhaps merited. The setting of GIT_DIR and GIT_WORK_TREE done by sequencer.c arose from a sequence of historical accidents: * When rebase was implemented as a shell command, it would call git-sh-setup, which among other things would set GIT_DIR -- but not export it. This meant that when rebase --exec commands were run via /bin/sh -c "$COMMAND" they would not inherit the GIT_DIR setting. The fact that GIT_DIR was not set in the run $COMMAND is the behavior we'd like to restore. * When the rebase--helper builtin was introduced to allow incrementally replacing shell with C code, we were in an implementation that was half shell, half C. In particular, commit 18633e1a22 ("rebase -i: use the rebase--helper builtin", 2017-02-09) added calls to exec git rebase--helper ... which caused rebase--helper to inherit the GIT_DIR environment variable from the shell. git's setup would change the environment variable from an absolute path to a relative one (".git"), but would leave it set. This meant that when rebase --exec commands were run via run_command_v_opt(...) they would inherit the GIT_DIR setting. * In commit 09d7b6c6fa ("sequencer: pass absolute GIT_DIR to exec commands", 2017-10-31), it was noted that the GIT_DIR caused problems with some commands; e.g. git rebase --exec 'cd subdir && git describe' ... would have GIT_DIR=.git which was invalid due to the change to the subdirectory. Instead of questioning why GIT_DIR was set, that commit instead made sequencer change GIT_DIR to be an absolute path and explicitly export it via argv_array_pushf(&child_env, "GIT_DIR=%s", absolute_path(get_git_dir())); run_command_v_opt_cd_env(..., child_env.argv) * In commit ab5e67d751 ("sequencer: pass absolute GIT_WORK_TREE to exec commands", 2018-07-14), it was noted that when GIT_DIR is set but GIT_WORK_TREE is not, that we do not discover GIT_WORK_TREE but just assume it is '.'. That is incorrect if trying to run commands from a subdirectory. However, rather than question why GIT_DIR was set, that commit instead also added GIT_WORK_TREE to the list of things to export. Each of the above problems would have been fixed automatically when git-rebase become a full builtin, had it not been for the fact that sequencer.c started exporting GIT_DIR and GIT_WORK_TREE in the interim. Stop exporting them now. Signed-off-by: Elijah Newren Acked-by: Johannes Schindelin --- sequencer: fix environment that 'exec' commands run under I'm not sure if the added regression tests make sense, or if t3409 is the best place to put them (taking over a recently removed t3409 that was used for the deprecated preserve merges option). Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-git-1134%2Fnewren%2Ffix-rebase-exec-environ-v1 Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-git-1134/newren/fix-rebase-exec-environ-v1 Pull-Request: https://github.com/git/git/pull/1134 sequencer.c | 9 +-------- t/t3409-rebase-environ.sh | 23 +++++++++++++++++++++++ 2 files changed, 24 insertions(+), 8 deletions(-) create mode 100755 t/t3409-rebase-environ.sh diff --git a/sequencer.c b/sequencer.c index ea96837cde3..9afdbe3e3d1 100644 --- a/sequencer.c +++ b/sequencer.c @@ -3495,17 +3495,12 @@ static int error_failed_squash(struct repository *r, static int do_exec(struct repository *r, const char *command_line) { - struct strvec child_env = STRVEC_INIT; const char *child_argv[] = { NULL, NULL }; int dirty, status; fprintf(stderr, _("Executing: %s\n"), command_line); child_argv[0] = command_line; - strvec_pushf(&child_env, "GIT_DIR=%s", absolute_path(get_git_dir())); - strvec_pushf(&child_env, "GIT_WORK_TREE=%s", - absolute_path(get_git_work_tree())); - status = run_command_v_opt_cd_env(child_argv, RUN_USING_SHELL, NULL, - child_env.v); + status = run_command_v_opt(child_argv, RUN_USING_SHELL); /* force re-reading of the cache */ if (discard_index(r->index) < 0 || repo_read_index(r) < 0) @@ -3535,8 +3530,6 @@ static int do_exec(struct repository *r, const char *command_line) status = 1; } - strvec_clear(&child_env); - return status; } diff --git a/t/t3409-rebase-environ.sh b/t/t3409-rebase-environ.sh new file mode 100755 index 00000000000..83ffb39d9ff --- /dev/null +++ b/t/t3409-rebase-environ.sh @@ -0,0 +1,23 @@ +#!/bin/sh + +test_description='git rebase interactive environment' + +. ./test-lib.sh + +test_expect_success 'setup' ' + test_commit one && + test_commit two && + test_commit three +' + +test_expect_success 'rebase --exec does not muck with GIT_DIR' ' + git rebase --exec "printf %s \$GIT_DIR >environ" HEAD~1 && + test_must_be_empty environ +' + +test_expect_success 'rebase --exec does not muck with GIT_WORK_TREE' ' + git rebase --exec "printf %s \$GIT_WORK_TREE >environ" HEAD~1 && + test_must_be_empty environ +' + +test_done base-commit: 88d915a634b449147855041d44875322de2b286d -- gitgitgadget