[T106][ZXW-22]7520V3SCV2.01.01.02P42U09_VEC_V0.8_AP_VEC origin source commit

Change-Id: Ic6e05d89ecd62fc34f82b23dcf306c93764aec4b
diff --git a/ap/app/busybox/src/util-linux/rdev.c b/ap/app/busybox/src/util-linux/rdev.c
new file mode 100644
index 0000000..4652817
--- /dev/null
+++ b/ap/app/busybox/src/util-linux/rdev.c
@@ -0,0 +1,33 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * rdev - print device node associated with a filesystem
+ *
+ * Copyright (c) 2008 Nuovation System Designs, LLC
+ *   Grant Erickson <gerickson@nuovations.com>
+ *
+ * Licensed under GPLv2, see file LICENSE in this source tree.
+ *
+ */
+
+//usage:#define rdev_trivial_usage
+//usage:       ""
+//usage:#define rdev_full_usage "\n\n"
+//usage:       "Print the device node associated with the filesystem mounted at '/'"
+//usage:
+//usage:#define rdev_example_usage
+//usage:       "$ rdev\n"
+//usage:       "/dev/mtdblock9 /\n"
+
+#include "libbb.h"
+
+int rdev_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int rdev_main(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
+{
+	const char *root_device = find_block_device("/");
+
+	if (root_device) {
+		printf("%s /\n", root_device);
+		return EXIT_SUCCESS;
+	}
+	return EXIT_FAILURE;
+}