From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michael Haggerty Subject: [PATCH v3 07/25] lock_file(): always add lock_file object to lock_file_list Date: Mon, 14 Apr 2014 15:54:37 +0200 Message-ID: <1397483695-10888-8-git-send-email-mhagger@alum.mit.edu> References: <1397483695-10888-1-git-send-email-mhagger@alum.mit.edu> Cc: git@vger.kernel.org, Johannes Sixt , Jeff King , =?UTF-8?q?Torsten=20B=C3=B6gershausen?= , Eric Sunshine , Michael Haggerty To: Junio C Hamano X-From: git-owner@vger.kernel.org Mon Apr 14 15:55:32 2014 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 1WZhMA-0000Ae-CS for gcvg-git-2@plane.gmane.org; Mon, 14 Apr 2014 15:55:30 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755152AbaDNNzV (ORCPT ); Mon, 14 Apr 2014 09:55:21 -0400 Received: from alum-mailsec-scanner-3.mit.edu ([18.7.68.14]:48563 "EHLO alum-mailsec-scanner-3.mit.edu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755102AbaDNNzS (ORCPT ); Mon, 14 Apr 2014 09:55:18 -0400 X-AuditID: 1207440e-f79c76d000003e2c-d6-534be8c5cced Received: from outgoing-alum.mit.edu (OUTGOING-ALUM.MIT.EDU [18.7.68.33]) by alum-mailsec-scanner-3.mit.edu (Symantec Messaging Gateway) with SMTP id F6.7E.15916.5C8EB435; Mon, 14 Apr 2014 09:55:17 -0400 (EDT) Received: from michael.fritz.box (p4FC96FF6.dip0.t-ipconnect.de [79.201.111.246]) (authenticated bits=0) (User authenticated as mhagger@ALUM.MIT.EDU) by outgoing-alum.mit.edu (8.13.8/8.12.4) with ESMTP id s3EDt097010903 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=NOT); Mon, 14 Apr 2014 09:55:16 -0400 X-Mailer: git-send-email 1.9.1 In-Reply-To: <1397483695-10888-1-git-send-email-mhagger@alum.mit.edu> X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFvrJIsWRmVeSWpSXmKPExsUixO6iqHv0hXewwc7LmhZdV7qZLBp6rzBb rPxZY3F7xXxmi1+Hn7Bb/GjpYbY486aR0aKz4yujA4fH3/cfmDx2zrrL7vGsdw+jx8VLyh6L H3h5fN4k53H3/04mj9vPtrEEcERx2yQllpQFZ6bn6dslcGe0LV3AWLBZoOL0hEnsDYzzebsY OTkkBEwk1kxZyAxhi0lcuLeerYuRi0NI4DKjxO1dm1ghnJNMEj82XWABqWIT0JVY1NPMBGKL CKhJTGw7xAJSxCzQziRxaEcvWEJYIETicW8TmM0ioCox//0MsGZeAReJDTvnsUOsk5M4eWwy 0AYODk4BV4mFH7JAwkJAJXe/TGGdwMi7gJFhFaNcYk5prm5uYmZOcWqybnFyYl5eapGusV5u ZoleakrpJkZIMPLtYGxfL3OIUYCDUYmHt2OOd7AQa2JZcWXuIUZJDiYlUd6MG0AhvqT8lMqM xOKM+KLSnNTiQ4wSHMxKIryuW4FyvCmJlVWpRfkwKWkOFiVxXrUl6n5CAumJJanZqakFqUUw WRkODiUJXvvnQI2CRanpqRVpmTklCGkmDk6Q4VxSIsWpeSmpRYmlJRnxoNiILwZGB0iKB2hv Ekg7b3FBYi5QFKL1FKOilDhvCUhCACSRUZoHNxaWYl4xigN9KcybBlLFA0xPcN2vgAYzAQ1m aQcbXJKIkJJqYMyXXc+YbXJs39oYj8U8P5oWM+x0+CJ88UBgwBS1j++aOxZzfIkpz4vZdeRw U6C/Pp/0xL/XGlidz64PmJQfU2lcFfbnwwSLhUKdG/59er7s0SqhPdJnDNltZjgd Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: It used to be that if locking failed, lock_file() usually did not register the lock_file object in lock_file_list but sometimes it did. This confusion was compounded if lock_file() was called via hold_lock_file_for_append(), which has its own failure modes. The ambiguity didn't have any ill effects, because lock_file objects cannot be removed from the lock_file_list anyway. But it is unnecessary to leave this behavior inconsistent. So change lock_file() to *always* ensure that the lock_file object is registered in lock_file_list regardless of whether an error occurs. Signed-off-by: Michael Haggerty --- lockfile.c | 25 ++++++++++++++++--------- 1 file changed, 16 insertions(+), 9 deletions(-) diff --git a/lockfile.c b/lockfile.c index e78a35f..120a6d6 100644 --- a/lockfile.c +++ b/lockfile.c @@ -130,6 +130,22 @@ static int lock_file(struct lock_file *lk, const char *path, int flags) */ static const size_t max_path_len = sizeof(lk->filename) - 5; + if (!lock_file_list) { + /* One-time initialization */ + sigchain_push_common(remove_lock_file_on_signal); + atexit(remove_lock_file); + } + + if (!lk->on_list) { + /* Initialize *lk and add it to lock_file_list: */ + lk->fd = -1; + lk->owner = 0; + lk->on_list = 1; + lk->filename[0] = 0; + lk->next = lock_file_list; + lock_file_list = lk; + } + if (strlen(path) >= max_path_len) return -1; strcpy(lk->filename, path); @@ -138,16 +154,7 @@ static int lock_file(struct lock_file *lk, const char *path, int flags) strcat(lk->filename, ".lock"); lk->fd = open(lk->filename, O_RDWR | O_CREAT | O_EXCL, 0666); if (0 <= lk->fd) { - if (!lock_file_list) { - sigchain_push_common(remove_lock_file_on_signal); - atexit(remove_lock_file); - } lk->owner = getpid(); - if (!lk->on_list) { - lk->next = lock_file_list; - lock_file_list = lk; - lk->on_list = 1; - } if (adjust_shared_perm(lk->filename)) { error("cannot fix permission bits on %s", lk->filename); rollback_lock_file(lk); -- 1.9.1