[PATCH v4 2/3] refs.c: split delete_ref_loose() into a separate flag-for-deletion and commit phase

[Ronnie Sahlberg <sahlberg@google.com>]

Change delete_ref_loose()) to just flag that a ref is to be deleted but do
not actually unlink the files.
Change commit_ref_lock() so that it will unlink refs that are flagged for
deletion.
Change all callers of delete_ref_loose() to explicitely call commit_ref_lock()
to commit the deletion.

The new pattern for deleting loose refs thus become:

lock = lock_ref_sha1_basic() (or varient of)
delete_ref_loose(lock)
unlock_ref(lock) | commit_ref_lock(lock)

Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
---
 refs.c | 32 ++++++++++++++++++++------------
 refs.h |  2 ++
 2 files changed, 22 insertions(+), 12 deletions(-)

diff --git a/refs.c b/refs.c
index 646afd7..a14addb 100644
--- a/refs.c
+++ b/refs.c
@@ -2484,16 +2484,9 @@ static int repack_without_ref(const char *refname)
 
 static int delete_ref_loose(struct ref_lock *lock, int flag)
 {
-	if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
-		/* loose */
-		int err, i = strlen(lock->lk->filename) - 5; /* .lock */
-
-		lock->lk->filename[i] = 0;
-		err = unlink_or_warn(lock->lk->filename);
-		lock->lk->filename[i] = '.';
-		if (err && errno != ENOENT)
-			return 1;
-	}
+	lock->delete_ref = 1;
+	lock->delete_flag = flag;
+
 	return 0;
 }
 
@@ -2515,7 +2508,7 @@ int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
 
 	unlink_or_warn(git_path("logs/%s", lock->ref_name));
 	clear_loose_ref_cache(&ref_cache);
-	unlock_ref(lock);
+	ret |= commit_ref_lock(lock);
 	return ret;
 }
 
@@ -2868,7 +2861,20 @@ int write_ref_sha1(struct ref_lock *lock,
 
 int commit_ref_lock(struct ref_lock *lock)
 {
-	if (!lock->skipped_write && commit_ref(lock)) {
+	if (lock->delete_ref) {
+		int flag = lock->delete_flag;
+
+		if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
+			/* loose */
+			int err, i = strlen(lock->lk->filename) - 5; /* .lock */
+
+			lock->lk->filename[i] = 0;
+			err = unlink_or_warn(lock->lk->filename);
+			lock->lk->filename[i] = '.';
+			if (err && errno != ENOENT)
+				return 1;
+		}
+	} else if (!lock->skipped_write && commit_ref(lock)) {
 		error("Couldn't set %s", lock->ref_name);
 		unlock_ref(lock);
 		return -1;
@@ -3487,6 +3493,8 @@ int ref_transaction_commit(struct ref_transaction *transaction,
 		if (update->lock) {
 			delnames[delnum++] = update->refname;
 			ret |= delete_ref_loose(update->lock, update->type);
+			ret |= commit_ref_lock(update->lock);
+			update->lock = NULL;
 		}
 	}
 
diff --git a/refs.h b/refs.h
index f14a417..223be30 100644
--- a/refs.h
+++ b/refs.h
@@ -9,6 +9,8 @@ struct ref_lock {
 	int lock_fd;
 	int force_write;
 	int skipped_write;
+	int delete_ref;
+	int delete_flag;
 };
 
 struct ref_transaction;
-- 
1.9.1.505.gd05696d