move fsleep to common

common/base.sh

@@ -196,3 +196,37 @@ fix_sbin_path()
 	printf "%s\n" $PATH | grep -Fxq '/sbin' || PATH="/sbin:$PATH"
 	export PATH
 }
+
+fsleep_setup()
+{
+    [ -n "$FSLEEP" ] || {
+	if sleep 0.1 2>/dev/null; then
+		FSLEEP=1
+	elif busybox usleep 1 2>/dev/null; then
+		FSLEEP=2
+	else
+		local errtext=$(read -t 0.001 2>&1)
+		if [ -z "$errtext" ]; then
+			FSLEEP=3
+		else
+			FSLEEP=0
+		fi
+	fi
+    }
+}
+minsleep()
+{
+    case "$FSLEEP" in
+	1)
+		sleep 0.1
+		;;
+	2)
+		busybox usleep 100000
+		;;
+	3)
+		read -t 0.1
+		;;
+    	*)
+		sleep 1
+    esac
+}