[PATCH 29/29] lock_ref_sha1_basic(): only handle REF_NODEREF mode

[Michael Haggerty <mhagger@alum.mit.edu>]

Now lock_ref_sha1_basic() is only called with flags==REF_NODEREF. So we
don't have to handle other cases anymore.

This enables several simplifications, the most interesting of which come
from the fact that ref_lock::orig_ref_name is now always the same as
ref_lock::ref_name:

* Remove ref_lock::orig_ref_name
* Remove local variable orig_refname from lock_ref_sha1_basic()
* commit_ref_update() never has to write to the reflog for
  lock->orig_ref_name

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
---
 refs/files-backend.c | 54 ++++++++++++++++++++--------------------------------
 1 file changed, 21 insertions(+), 33 deletions(-)

diff --git a/refs/files-backend.c b/refs/files-backend.c
index 938871b..5dca352 100644
--- a/refs/files-backend.c
+++ b/refs/files-backend.c
@@ -7,7 +7,6 @@
 
 struct ref_lock {
 	char *ref_name;
-	char *orig_ref_name;
 	struct lock_file *lk;
 	struct object_id old_oid;
 };
@@ -1551,7 +1550,6 @@ static void unlock_ref(struct ref_lock *lock)
 	if (lock->lk)
 		rollback_lock_file(lock->lk);
 	free(lock->ref_name);
-	free(lock->orig_ref_name);
 	free(lock);
 }
 
@@ -1605,7 +1603,6 @@ static int lock_raw_ref(const char *refname, int deleting, int mustexist,
 	*lock_p = lock = xcalloc(1, sizeof(*lock));
 
 	lock->ref_name = xstrdup(refname);
-	lock->orig_ref_name = xstrdup(refname);
 	strbuf_git_path(&ref_file, "%s", refname);
 
 retry:
@@ -1991,14 +1988,13 @@ static struct ref_lock *lock_ref_sha1_basic(const char *refname,
 					    struct strbuf *err)
 {
 	struct strbuf ref_file = STRBUF_INIT;
-	struct strbuf orig_ref_file = STRBUF_INIT;
-	const char *orig_refname = refname;
 	struct ref_lock *lock;
 	int last_errno = 0;
-	int lflags = 0;
+	int lflags = LOCK_NO_DEREF;
 	int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
-	int resolve_flags = 0;
+	int resolve_flags = RESOLVE_REF_NO_RECURSE;
 	int attempts_remaining = 3;
+	int resolved;
 
 	assert(err);
 
@@ -2008,46 +2004,39 @@ static struct ref_lock *lock_ref_sha1_basic(const char *refname,
 		resolve_flags |= RESOLVE_REF_READING;
 	if (flags & REF_DELETING)
 		resolve_flags |= RESOLVE_REF_ALLOW_BAD_NAME;
-	if (flags & REF_NODEREF) {
-		resolve_flags |= RESOLVE_REF_NO_RECURSE;
-		lflags |= LOCK_NO_DEREF;
-	}
 
-	refname = resolve_ref_unsafe(refname, resolve_flags,
-				     lock->old_oid.hash, type);
-	if (!refname && errno == EISDIR) {
+	resolved = !!resolve_ref_unsafe(refname, resolve_flags,
+					lock->old_oid.hash, type);
+	if (!resolved && errno == EISDIR) {
 		/*
 		 * we are trying to lock foo but we used to
 		 * have foo/bar which now does not exist;
 		 * it is normal for the empty directory 'foo'
 		 * to remain.
 		 */
-		strbuf_git_path(&orig_ref_file, "%s", orig_refname);
-		if (remove_empty_directories(&orig_ref_file)) {
+		strbuf_git_path(&ref_file, "%s", refname);
+		if (remove_empty_directories(&ref_file)) {
 			last_errno = errno;
-			if (!verify_refname_available_dir(orig_refname, extras, skip,
+			if (!verify_refname_available_dir(refname, extras, skip,
 							  get_loose_refs(&ref_cache), err))
 				strbuf_addf(err, "there are still refs under '%s'",
-					    orig_refname);
+					    refname);
 			goto error_return;
 		}
-		refname = resolve_ref_unsafe(orig_refname, resolve_flags,
-					     lock->old_oid.hash, type);
+		resolved = !!resolve_ref_unsafe(refname, resolve_flags,
+						lock->old_oid.hash, type);
 	}
-	if (!refname) {
+	if (!resolved) {
 		last_errno = errno;
 		if (last_errno != ENOTDIR ||
-		    !verify_refname_available_dir(orig_refname, extras, skip,
+		    !verify_refname_available_dir(refname, extras, skip,
 						  get_loose_refs(&ref_cache), err))
 			strbuf_addf(err, "unable to resolve reference '%s': %s",
-				    orig_refname, strerror(last_errno));
+				    refname, strerror(last_errno));
 
 		goto error_return;
 	}
 
-	if (flags & REF_NODEREF)
-		refname = orig_refname;
-
 	/*
 	 * If the ref did not exist and we are creating it, make sure
 	 * there is no existing packed ref whose name begins with our
@@ -2064,7 +2053,7 @@ static struct ref_lock *lock_ref_sha1_basic(const char *refname,
 	lock->lk = xcalloc(1, sizeof(struct lock_file));
 
 	lock->ref_name = xstrdup(refname);
-	lock->orig_ref_name = xstrdup(orig_refname);
+	strbuf_reset(&ref_file);
 	strbuf_git_path(&ref_file, "%s", refname);
 
  retry:
@@ -2108,7 +2097,6 @@ static struct ref_lock *lock_ref_sha1_basic(const char *refname,
 
  out:
 	strbuf_release(&ref_file);
-	strbuf_release(&orig_ref_file);
 	errno = last_errno;
 	return lock;
 }
@@ -2873,9 +2861,7 @@ static int commit_ref_update(struct ref_lock *lock,
 			     struct strbuf *err)
 {
 	clear_loose_ref_cache(&ref_cache);
-	if (log_ref_write(lock->ref_name, lock->old_oid.hash, sha1, logmsg, 0, err) < 0 ||
-	    (strcmp(lock->ref_name, lock->orig_ref_name) &&
-	     log_ref_write(lock->orig_ref_name, lock->old_oid.hash, sha1, logmsg, 0, err) < 0)) {
+	if (log_ref_write(lock->ref_name, lock->old_oid.hash, sha1, logmsg, 0, err)) {
 		char *old_msg = strbuf_detach(err, NULL);
 		strbuf_addf(err, "cannot update the ref '%s': %s",
 			    lock->ref_name, old_msg);
@@ -2883,7 +2869,8 @@ static int commit_ref_update(struct ref_lock *lock,
 		unlock_ref(lock);
 		return -1;
 	}
-	if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
+
+	if (strcmp(lock->ref_name, "HEAD") != 0) {
 		/*
 		 * Special hack: If a branch is updated directly and HEAD
 		 * points to it (may happen on the remote side of a push
@@ -2899,6 +2886,7 @@ static int commit_ref_update(struct ref_lock *lock,
 		unsigned char head_sha1[20];
 		int head_flag;
 		const char *head_ref;
+
 		head_ref = resolve_ref_unsafe("HEAD", RESOLVE_REF_READING,
 					      head_sha1, &head_flag);
 		if (head_ref && (head_flag & REF_ISSYMREF) &&
@@ -2911,6 +2899,7 @@ static int commit_ref_update(struct ref_lock *lock,
 			}
 		}
 	}
+
 	if (commit_ref(lock)) {
 		strbuf_addf(err, "couldn't set '%s'", lock->ref_name);
 		unlock_ref(lock);
@@ -3016,7 +3005,6 @@ int set_worktree_head_symref(const char *gitdir, const char *target)
 	lock = xcalloc(1, sizeof(struct ref_lock));
 	lock->lk = &head_lock;
 	lock->ref_name = xstrdup(head_rel);
-	lock->orig_ref_name = xstrdup(head_rel);
 
 	ret = create_symref_locked(lock, head_rel, target, NULL);
 
-- 
2.8.1