diff --git a/vcs-svn/svndiff.h b/vcs-svn/svndiff.h
--- /dev/null
+++ b/vcs-svn/svndiff.h
@@ -0,0 +1,10 @@
+#ifndef SVNDIFF_H_
+#define SVNDIFF_H_
+
+struct line_buffer;
+struct sliding_view;
+
+extern int svndiff0_apply(struct line_buffer *delta, off_t delta_len,
+ struct sliding_view *preimage, FILE *postimage);
+
+#endif