submodule.c: describe submodule_to_gitdir() in a new comment

Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/submodule.c b/submodule.c
index b12600f..50bf3fb 100644 (file)
--- a/submodule.c
+++ b/submodule.c
@@ -1997,6 +1997,10 @@ const char *get_superproject_working_tree(void)
        return ret;
 }
 
+/*
+ * Put the gitdir for a submodule (given relative to the main
+ * repository worktree) into `buf`, or return -1 on error.
+ */
 int submodule_to_gitdir(struct strbuf *buf, const char *submodule)
 {
        const struct submodule *sub;