From: "Martin Ågren" <martin.agren@gmail.com>
To: git@vger.kernel.org
Cc: Jeff King <peff@peff.net>, Paul Tan <pyokagan@gmail.com>,
Junio C Hamano <gitster@pobox.com>
Subject: [PATCH v2 06/12] cache-tree: simplify locking logic
Date: Thu, 5 Oct 2017 22:32:08 +0200 [thread overview]
Message-ID: <c9c03b3136a2881c393ab6a6712571dee7a498ed.1507228170.git.martin.agren@gmail.com> (raw)
In-Reply-To: <cover.1507228170.git.martin.agren@gmail.com>
After we have taken the lock using `LOCK_DIE_ON_ERROR`, we know that
`newfd` is non-negative. So when we check for exactly that property
before calling `write_locked_index()`, the outcome is guaranteed.
If we write and commit successfully, we set `newfd = -1`, so that we can
later avoid calling `rollback_lock_file` on an already-committed lock.
But we might just as well unconditionally call `rollback_lock_file()` --
it will be a no-op if we have already committed.
All in all, we use `newfd` as a bool and the only benefit we get from it
is that we can avoid calling a no-op. Remove `newfd` so that we have one
variable less to reason about.
Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
v2: Identical.
cache-tree.c | 12 ++++--------
1 file changed, 4 insertions(+), 8 deletions(-)
diff --git a/cache-tree.c b/cache-tree.c
index 71d092ed5..f646f5673 100644
--- a/cache-tree.c
+++ b/cache-tree.c
@@ -602,11 +602,11 @@ static struct cache_tree *cache_tree_find(struct cache_tree *it, const char *pat
int write_index_as_tree(unsigned char *sha1, struct index_state *index_state, const char *index_path, int flags, const char *prefix)
{
- int entries, was_valid, newfd;
+ int entries, was_valid;
struct lock_file lock_file = LOCK_INIT;
int ret = 0;
- newfd = hold_lock_file_for_update(&lock_file, index_path, LOCK_DIE_ON_ERROR);
+ hold_lock_file_for_update(&lock_file, index_path, LOCK_DIE_ON_ERROR);
entries = read_index_from(index_state, index_path);
if (entries < 0) {
@@ -625,10 +625,7 @@ int write_index_as_tree(unsigned char *sha1, struct index_state *index_state, co
ret = WRITE_TREE_UNMERGED_INDEX;
goto out;
}
- if (0 <= newfd) {
- if (!write_locked_index(index_state, &lock_file, COMMIT_LOCK))
- newfd = -1;
- }
+ write_locked_index(index_state, &lock_file, COMMIT_LOCK);
/* Not being able to write is fine -- we are only interested
* in updating the cache-tree part, and if the next caller
* ends up using the old index with unupdated cache-tree part
@@ -650,8 +647,7 @@ int write_index_as_tree(unsigned char *sha1, struct index_state *index_state, co
hashcpy(sha1, index_state->cache_tree->oid.hash);
out:
- if (0 <= newfd)
- rollback_lock_file(&lock_file);
+ rollback_lock_file(&lock_file);
return ret;
}
--
2.14.2.666.gea220ee40
next prev parent reply other threads:[~2017-10-05 20:32 UTC|newest]
Thread overview: 69+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-10-01 14:56 [PATCH 00/11] various lockfile-leaks and -fixes Martin Ågren
2017-10-01 14:56 ` [PATCH 01/11] sha1_file: do not leak `lock_file` Martin Ågren
2017-10-02 5:26 ` Jeff King
2017-10-02 10:15 ` Martin Ågren
2017-10-01 14:56 ` [PATCH 02/11] treewide: prefer lockfiles on the stack Martin Ågren
2017-10-02 3:37 ` Junio C Hamano
2017-10-02 4:12 ` Martin Ågren
2017-10-02 5:34 ` Jeff King
2017-10-01 14:56 ` [PATCH 03/11] lockfile: fix documentation on `close_lock_file_gently()` Martin Ågren
2017-10-02 5:35 ` Jeff King
2017-10-01 14:56 ` [PATCH 04/11] tempfile: fix documentation on `delete_tempfile()` Martin Ågren
2017-10-02 5:38 ` Jeff King
2017-10-01 14:56 ` [PATCH 05/11] cache-tree: simplify locking logic Martin Ågren
2017-10-02 3:40 ` Junio C Hamano
2017-10-02 5:41 ` Jeff King
2017-10-01 14:56 ` [PATCH 06/11] apply: move lockfile into `apply_state` Martin Ågren
2017-10-02 5:48 ` Jeff King
2017-10-01 14:56 ` [PATCH 07/11] apply: remove `newfd` from `struct apply_state` Martin Ågren
2017-10-02 5:50 ` Jeff King
2017-10-01 14:56 ` [PATCH 08/11] cache.h: document `write_locked_index()` Martin Ågren
2017-10-01 14:56 ` [PATCH 09/11] read-cache: require flags for `write_locked_index()` Martin Ågren
2017-10-02 3:49 ` Junio C Hamano
2017-10-02 4:14 ` Martin Ågren
2017-10-02 10:16 ` Martin Ågren
2017-10-02 6:00 ` Jeff King
2017-10-01 14:56 ` [PATCH 10/11] read-cache: don't leave dangling pointer in `do_write_index()` Martin Ågren
2017-10-02 6:15 ` Jeff King
2017-10-02 6:20 ` Jeff King
2017-10-01 14:56 ` [PATCH 11/11] read-cache: roll back lock on error with `COMMIT_LOCK` Martin Ågren
2017-10-02 4:01 ` Junio C Hamano
2017-10-02 2:37 ` [PATCH 00/11] various lockfile-leaks and -fixes Junio C Hamano
2017-10-02 6:22 ` Jeff King
2017-10-02 6:30 ` Junio C Hamano
2017-10-02 10:19 ` Martin Ågren
2017-10-03 6:21 ` Junio C Hamano
2017-10-05 20:32 ` [PATCH v2 00/12] " Martin Ågren
2017-10-05 20:32 ` [PATCH v2 01/12] sha1_file: do not leak `lock_file` Martin Ågren
2017-10-06 1:17 ` Junio C Hamano
2017-10-05 20:32 ` [PATCH v2 02/12] treewide: prefer lockfiles on the stack Martin Ågren
2017-10-05 20:32 ` [PATCH v2 03/12] lockfile: fix documentation on `close_lock_file_gently()` Martin Ågren
2017-10-05 20:32 ` [PATCH v2 04/12] tempfile: fix documentation on `delete_tempfile()` Martin Ågren
2017-10-05 20:32 ` [PATCH v2 05/12] checkout-index: simplify locking logic Martin Ågren
2017-10-06 1:21 ` Junio C Hamano
2017-10-05 20:32 ` Martin Ågren [this message]
2017-10-05 20:32 ` [PATCH v2 07/12] apply: move lockfile into `apply_state` Martin Ågren
2017-10-05 20:32 ` [PATCH v2 08/12] apply: remove `newfd` from `struct apply_state` Martin Ågren
2017-10-05 20:32 ` [PATCH v2 09/12] cache.h: document `write_locked_index()` Martin Ågren
2017-10-05 20:32 ` [PATCH v2 10/12] read-cache: drop explicit `CLOSE_LOCK`-flag Martin Ågren
2017-10-06 1:39 ` Junio C Hamano
2017-10-06 11:02 ` Martin Ågren
2017-10-05 20:32 ` [PATCH v2 11/12] read-cache: leave lock in right state in `write_locked_index()` Martin Ågren
2017-10-06 2:01 ` Junio C Hamano
2017-10-06 11:04 ` Martin Ågren
2017-10-06 12:02 ` Junio C Hamano
2017-10-06 19:44 ` Martin Ågren
2017-10-06 20:12 ` [PATCH v3 00/12] Re: various lockfile-leaks and -fixes Martin Ågren
2017-10-06 20:12 ` [PATCH v3 01/12] sha1_file: do not leak `lock_file` Martin Ågren
2017-10-06 20:12 ` [PATCH v3 02/12] treewide: prefer lockfiles on the stack Martin Ågren
2017-10-06 20:12 ` [PATCH v3 03/12] lockfile: fix documentation on `close_lock_file_gently()` Martin Ågren
2017-10-06 20:12 ` [PATCH v3 04/12] tempfile: fix documentation on `delete_tempfile()` Martin Ågren
2017-10-06 20:12 ` [PATCH v3 05/12] checkout-index: simplify locking logic Martin Ågren
2017-10-06 20:12 ` [PATCH v3 06/12] cache-tree: " Martin Ågren
2017-10-06 20:12 ` [PATCH v3 07/12] apply: move lockfile into `apply_state` Martin Ågren
2017-10-06 20:12 ` [PATCH v3 08/12] apply: remove `newfd` from `struct apply_state` Martin Ågren
2017-10-06 20:12 ` [PATCH v3 09/12] cache.h: document `write_locked_index()` Martin Ågren
2017-10-06 20:12 ` [PATCH v3 10/12] read-cache: drop explicit `CLOSE_LOCK`-flag Martin Ågren
2017-10-06 20:12 ` [PATCH v3 11/12] read-cache: leave lock in right state in `write_locked_index()` Martin Ågren
2017-10-06 20:12 ` [PATCH v3 12/12] read_cache: roll back lock in `update_index_if_able()` Martin Ågren
2017-10-05 20:32 ` [PATCH v2 " Martin Ågren
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