1 files changed, 48 insertions, 0 deletions
diff --git a/service/java/com/android/server/wifi/util/StringUtil.java b/service/java/com/android/server/wifi/util/StringUtil.java
new file mode 100644
index 000000000..813b85b95
--- /dev/null
+++ b/service/java/com/android/server/wifi/util/StringUtil.java
@@ -0,0 +1,48 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server.wifi.util;
+
+/** Basic string utilities */
+public class StringUtil {
+    static final byte ASCII_PRINTABLE_MIN = ' ';
+    static final byte ASCII_PRINTABLE_MAX = '~';
+
+    /** Returns true if-and-only-if |byteArray| can be safely printed as ASCII. */
+    public static boolean isAsciiPrintable(byte[] byteArray) {
+        if (byteArray == null) {
+            return true;
+        }
+
+        for (byte b : byteArray) {
+            switch (b) {
+                // Control characters which actually are printable. Fall-throughs are deliberate.
+                case 0x07:      // bell ('\a' not recognized in Java)
+                case '\f':      // form feed
+                case '\n':      // new line
+                case '\t':      // horizontal tab
+                case 0x0b:      // vertical tab ('\v' not recognized in Java)
+                    continue;
+            }
+
+            if (b < ASCII_PRINTABLE_MIN || b > ASCII_PRINTABLE_MAX) {
+                return false;
+            }
+        }
+
+        return true;
+    }
+}