+#endif
+
+#ifdef USE_PGSQL
+#ifdef USE_MYSQL
+#error ONLY one of USE_MYSQL and USE_PGSQL should be defined
+#endif
+
+#include <postgres.h>
+#include <fmgr.h>
+
+Datum
+tile_for_point(PG_FUNCTION_ARGS)
+{
+ double lat = PG_GETARG_INT32(0) / 10000000.0;
+ double lon = PG_GETARG_INT32(1) / 10000000.0;
+
+ PG_RETURN_INT64(xy2tile(lon2x(lon), lat2y(lat)));
+}
+
+PG_FUNCTION_INFO_V1(tile_for_point);
+
+/*
+ * To bind this into PGSQL, try something like:
+ *
+ * CREATE FUNCTION tile_for_point(int4, int4) RETURNS int8
+ * AS '/path/to/rails-port/db/functions/libpgosm', 'tile_for_point'
+ * LANGUAGE C STRICT;
+ *
+ * (without all the *s)
+ */
+
+#endif