- Add Util.isUUID

- Add tests for Util.isUUID
- First part of the fix for protocol interoperability between viewer 1.20 and 1.21 for friend offers.

OpenSim/Framework/Util.cs

@@ -64,6 +64,8 @@ namespace OpenSim.Framework
         private static readonly DateTime unixEpoch =
             DateTime.ParseExact("1970-01-01 00:00:00 +0", "yyyy-MM-dd hh:mm:ss z", DateTimeFormatInfo.InvariantInfo).ToUniversalTime();
 
+        private static readonly Regex UUIDPattern = new Regex("^[0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{12}$");
+
         #region Vector Equations
 
         /// <summary>
@@ -796,5 +798,10 @@ namespace OpenSim.Framework
             x += rx;
             y += ry;
         }
+
+        public static bool isUUID(string s)
+        {
+            return UUIDPattern.IsMatch(s);
+        }
     }
 }