Pass over a notes ref that names no tree

A pusher can point refs/notes/commits or a signature notes ref at any
object, and git dies loading one that is no tree, which ended every page
of the repository, the dumb transport included. Such a ref now counts
as absent.

1 file changed, 6 insertions, 1 deletion

diff --git a/source/ui-snapshot.c b/source/ui-snapshot.cindex 32d40f8..6a059a0 100644--- a/source/ui-snapshot.c+++ b/source/ui-snapshot.c@@ -311,7 +311,12 @@ const struct object_id *cgit_snapshot_get_sig(const char *ref, const struct cgit 		// dropped, so plain tar is refs/notes/signatures/tar. 		strbuf_addf(&notes_ref, "refs/notes/signatures/%s", f->suffix + 1); -		init_notes(tree, notes_ref.buf, combine_notes_ignore, 0);+		// A ref that names no tree is passed over, since git would die+		// loading it, and a signature it cannot hold is just absent.+		if (cgit_notes_ref_usable(notes_ref.buf))+			init_notes(tree, notes_ref.buf, combine_notes_ignore, 0);+		else+			init_notes(tree, notes_ref.buf, combine_notes_ignore, NOTES_INIT_EMPTY); 		strbuf_release(&notes_ref); 	} 
diff --git a/source/ui-snapshot.c b/source/ui-snapshot.c
index 32d40f8..6a059a0 100644
--- a/source/ui-snapshot.c
+++ b/source/ui-snapshot.c
@@ -311,7 +311,12 @@ const struct object_id *cgit_snapshot_get_sig(const char *ref, const struct cgit
 		// dropped, so plain tar is refs/notes/signatures/tar.
 		strbuf_addf(&notes_ref, "refs/notes/signatures/%s", f->suffix + 1);
 
-		init_notes(tree, notes_ref.buf, combine_notes_ignore, 0);
+		// A ref that names no tree is passed over, since git would die
+		// loading it, and a signature it cannot hold is just absent.
+		if (cgit_notes_ref_usable(notes_ref.buf))
+			init_notes(tree, notes_ref.buf, combine_notes_ignore, 0);
+		else
+			init_notes(tree, notes_ref.buf, combine_notes_ignore, NOTES_INIT_EMPTY);
 		strbuf_release(&notes_ref);
 	}