diff options
authorJunio C Hamano <>2016-12-07 18:56:26 (GMT)
committerJunio C Hamano <>2016-12-07 19:31:59 (GMT)
commit3f061bf514667497a948804828064b9b9c3b249b (patch)
parentb3e83cc752e905e063d0930c682a06de5034074f (diff)
The "libify sequencer" topic stopped passing the die_on_error option to hold_locked_index(), and this lost an error message from "git merge --ff-only $commit" when there are competing updates in progress. The command still exits with a non-zero status, but that is not of much help for an interactive user. The last thing the command says is "Updating $from..$to". We used to follow it with a big error message that makes it clear that "merge --ff-only" did not succeed. What is sad is that we should have noticed this regression while reviewing the change. It was clear that the update to the checkout_fast_forward() function made a failing hold_locked_index() silent, but the only caller of the checkout_fast_forward() function had this comment: if (checkout_fast_forward(from, to, 1)) - exit(128); /* the callee should have complained already */ + return -1; /* the callee should have complained already */ which clearly contradicted the assumption X-<. Add a new option LOCK_REPORT_ON_ERROR that can be passed instead of LOCK_DIE_ON_ERROR to the hold_lock*() family of functions and teach checkout_fast_forward() to use it to fix this regression. After going thourgh all calls to hold_lock*() family of functions that used to pass LOCK_DIE_ON_ERROR but were modified to pass 0 in the "libify sequencer" topic "git show --first-parent 2a4062a4a8", it appears that this is the only one that has become silent. Many others used to give detailed report that talked about "there may be competing Git process running" but with the series merged they now only give a single liner "Unable to lock ...", some of which may have to be tweaked further, but at least they say something, unlike the one this patch fixes. Reported-by: Robbie Iannucci <> Signed-off-by: Junio C Hamano <>
3 files changed, 18 insertions, 4 deletions
diff --git a/lockfile.c b/lockfile.c
index 9268cdf..aa69210 100644
--- a/lockfile.c
+++ b/lockfile.c
@@ -174,8 +174,16 @@ int hold_lock_file_for_update_timeout(struct lock_file *lk, const char *path,
int flags, long timeout_ms)
int fd = lock_file_timeout(lk, path, flags, timeout_ms);
- if (fd < 0 && (flags & LOCK_DIE_ON_ERROR))
- unable_to_lock_die(path, errno);
+ if (fd < 0) {
+ if (flags & LOCK_DIE_ON_ERROR)
+ unable_to_lock_die(path, errno);
+ if (flags & LOCK_REPORT_ON_ERROR) {
+ struct strbuf buf = STRBUF_INIT;
+ unable_to_lock_message(path, errno, &buf);
+ error("%s", buf.buf);
+ strbuf_release(&buf);
+ }
+ }
return fd;
diff --git a/lockfile.h b/lockfile.h
index d26ad27..16775a7 100644
--- a/lockfile.h
+++ b/lockfile.h
@@ -129,11 +129,17 @@ struct lock_file {
* If a lock is already taken for the file, `die()` with an error
* message. If this flag is not specified, trying to lock a file that
- * is already locked returns -1 to the caller.
+ * is already locked silently returns -1 to the caller, or ...
+ * ... this flag can be passed instead to return -1 and give the usual
+ * error message upon an error.
+ */
* Usually symbolic links in the destination path are resolved. This
* means that (1) the lockfile is created by adding ".lock" to the
* resolved path, and (2) upon commit, the resolved path is
diff --git a/merge.c b/merge.c
index 23866c9..04ee5fc 100644
--- a/merge.c
+++ b/merge.c
@@ -57,7 +57,7 @@ int checkout_fast_forward(const unsigned char *head,
- if (hold_locked_index(lock_file, 0) < 0)
+ if (hold_locked_index(lock_file, LOCK_REPORT_ON_ERROR) < 0)
return -1;
memset(&trees, 0, sizeof(trees));