Convert lookup_tree to struct object_id

Convert the lookup_tree function to take a pointer to struct object_id.

The commit was created with manual changes to tree.c, tree.h, and
object.c, plus the following semantic patch:

@@
@@
- lookup_tree(EMPTY_TREE_SHA1_BIN)
+ lookup_tree(&empty_tree_oid)

@@
expression E1;
@@
- lookup_tree(E1.hash)
+ lookup_tree(&E1)

@@
expression E1;
@@
- lookup_tree(E1->hash)
+ lookup_tree(E1)

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

4 files changed, 5 insertions, 5 deletions

diff --git a/builtin/am.c b/builtin/am.c
index 650269ac5e..7663f12e64 100644
--- a/builtin/am.c
+++ b/builtin/am.c
@@ -1453,9 +1453,9 @@ static void write_index_patch(const struct am_state *state)
 	FILE *fp;
 
 	if (!get_sha1_tree("HEAD", head.hash))
-		tree = lookup_tree(head.hash);
+		tree = lookup_tree(&head);
 	else
-		tree = lookup_tree(EMPTY_TREE_SHA1_BIN);
+		tree = lookup_tree(&empty_tree_oid);
 
 	fp = xfopen(am_path(state, "patch"), "w");
 	init_revisions(&rev_info, NULL);
diff --git a/builtin/diff-tree.c b/builtin/diff-tree.c
index e85a449df1..95b8d1ba7c 100644
--- a/builtin/diff-tree.c
+++ b/builtin/diff-tree.c
@@ -44,7 +44,7 @@ static int stdin_diff_trees(struct tree *tree1, const char *p)
 	struct tree *tree2;
 	if (!isspace(*p++) || parse_oid_hex(p, &oid, &p) || *p)
 		return error("Need exactly two trees, separated by a space");
-	tree2 = lookup_tree(oid.hash);
+	tree2 = lookup_tree(&oid);
 	if (!tree2 || parse_tree(tree2))
 		return -1;
 	printf("%s %s\n", oid_to_hex(&tree1->object.oid),
diff --git a/builtin/diff.c b/builtin/diff.c
index a25b4e4ae6..895f928978 100644
--- a/builtin/diff.c
+++ b/builtin/diff.c
@@ -381,7 +381,7 @@ int cmd_diff(int argc, const char **argv, const char *prefix)
 				add_head_to_pending(&rev);
 				if (!rev.pending.nr) {
 					struct tree *tree;
-					tree = lookup_tree(EMPTY_TREE_SHA1_BIN);
+					tree = lookup_tree(&empty_tree_oid);
 					add_pending_object(&rev, &tree->object, "HEAD");
 				}
 				break;
diff --git a/builtin/reflog.c b/builtin/reflog.c
index 7866a03412..7e89e84dce 100644
--- a/builtin/reflog.c
+++ b/builtin/reflog.c
@@ -62,7 +62,7 @@ static int tree_is_complete(const struct object_id *oid)
 	int complete;
 	struct tree *tree;
 
-	tree = lookup_tree(oid->hash);
+	tree = lookup_tree(oid);
 	if (!tree)
 		return 0;
 	if (tree->object.flags & SEEN)