diff --git a/resolve-undo.h b/resolve-undo.h
--- /dev/null
+++ b/resolve-undo.h
@@ -0,0 +1,14 @@
+#ifndef RESOLVE_UNDO_H
+#define RESOLVE_UNDO_H
+
+struct resolve_undo_info {
+ unsigned int mode[3];
+ unsigned char sha1[3][20];
+};
+
+extern void record_resolve_undo(struct index_state *, struct cache_entry *);
+extern void resolve_undo_write(struct strbuf *, struct string_list *);
+extern struct string_list *resolve_undo_read(void *, unsigned long);
+extern void resolve_undo_clear_index(struct index_state *);
+
+#endif