[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/libbb/device_open.c b/ap/app/busybox/src/libbb/device_open.c
new file mode 100644
index 0000000..a8fe2fc
--- /dev/null
+++ b/ap/app/busybox/src/libbb/device_open.c
@@ -0,0 +1,32 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * Utility routines.
+ *
+ * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
+ *
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
+ */
+
+#include "libbb.h"
+
+/* try to open up the specified device */
+int FAST_FUNC device_open(const char *device, int mode)
+{
+	int m, f, fd;
+
+	m = mode | O_NONBLOCK;
+
+	/* Retry up to 5 times */
+	/* TODO: explain why it can't be considered insane */
+	for (f = 0; f < 5; f++) {
+		fd = open(device, m, 0600);
+		if (fd >= 0)
+			break;
+	}
+	if (fd < 0)
+		return fd;
+	/* Reset original flags. */
+	if (m != mode)
+		fcntl(fd, F_SETFL, mode);
+	return fd;
+}