[lib][cbuf] simple circular buffer implementation
diff --git a/lib/cbuf/rules.mk b/lib/cbuf/rules.mk
new file mode 100644
index 0000000..2c57d48
--- /dev/null
+++ b/lib/cbuf/rules.mk
@@ -0,0 +1,4 @@
+LOCAL_DIR := $(GET_LOCAL_DIR)
+
+OBJS += \
+	$(LOCAL_DIR)/cbuf.o