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: AS31976 209.132.180.0/23 X-Spam-Status: No, score=-3.2 required=3.0 tests=AWL,BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by dcvr.yhbt.net (Postfix) with ESMTP id BF3301F453 for ; Wed, 20 Feb 2019 16:16:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726326AbfBTQQy (ORCPT ); Wed, 20 Feb 2019 11:16:54 -0500 Received: from mx2.suse.de ([195.135.220.15]:38340 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725877AbfBTQQx (ORCPT ); Wed, 20 Feb 2019 11:16:53 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id BA661ADD1; Wed, 20 Feb 2019 16:16:52 +0000 (UTC) From: Michal Suchanek To: git@vger.kernel.org Cc: Michal Suchanek , Eric Sunshine , Marketa Calabkova , =?UTF-8?q?Nguy=E1=BB=85n=20Th=C3=A1i=20Ng=E1=BB=8Dc=20Duy?= , Junio C Hamano Subject: [PATCH v3 1/2] worktree: fix worktree add race. Date: Wed, 20 Feb 2019 17:16:48 +0100 Message-Id: X-Mailer: git-send-email 2.20.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Git runs a stat loop to find a worktree name that's available and then does mkdir on the found name. Turn it to mkdir loop to avoid another invocation of worktree add finding the same free name and creating the directory first. Signed-off-by: Michal Suchanek --- v2: - simplify loop exit condition - exit early if the mkdir fails for reason other than already present worktree - make counter unsigned --- builtin/worktree.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/builtin/worktree.c b/builtin/worktree.c index 3f9907fcc994..85a604cfe98c 100644 --- a/builtin/worktree.c +++ b/builtin/worktree.c @@ -268,10 +268,10 @@ static int add_worktree(const char *path, const char *refname, struct strbuf sb_git = STRBUF_INIT, sb_repo = STRBUF_INIT; struct strbuf sb = STRBUF_INIT; const char *name; - struct stat st; struct child_process cp = CHILD_PROCESS_INIT; struct argv_array child_env = ARGV_ARRAY_INIT; - int counter = 0, len, ret; + unsigned int counter = 0; + int len, ret; struct strbuf symref = STRBUF_INIT; struct commit *commit = NULL; int is_branch = 0; @@ -295,8 +295,12 @@ static int add_worktree(const char *path, const char *refname, if (safe_create_leading_directories_const(sb_repo.buf)) die_errno(_("could not create leading directories of '%s'"), sb_repo.buf); - while (!stat(sb_repo.buf, &st)) { + + while (mkdir(sb_repo.buf, 0777)) { counter++; + if ((errno != EEXIST) || !counter /* overflow */) + die_errno(_("could not create directory of '%s'"), + sb_repo.buf); strbuf_setlen(&sb_repo, len); strbuf_addf(&sb_repo, "%d", counter); } @@ -306,8 +310,6 @@ static int add_worktree(const char *path, const char *refname, atexit(remove_junk); sigchain_push_common(remove_junk_on_signal); - if (mkdir(sb_repo.buf, 0777)) - die_errno(_("could not create directory of '%s'"), sb_repo.buf); junk_git_dir = xstrdup(sb_repo.buf); is_junk = 1; -- 2.20.1