Fix descriptor events (#31)

Author: AdrianSoundy

nanoFramework.Device.Bluetooth/BluetoothEventListener.cs

@@ -30,10 +30,10 @@ public BaseEvent ProcessEvent(uint data1, uint data2,  DateTime time)
                 // Data1, Data2 is packed by PostManagedEvent, so we need to unpack the high word.
                 //
                 // Data1
-                // DDCC00TT where DD = descriptorId, CC = characteristicId, TT = BluetoothEventType
+                // DDCC00TT where DDCC = descriptorId, CC = characteristicId, TT = BluetoothEventType
                 type = (BluetoothEventType)(data1 & 0xff),
                 characteristicId = (ushort)((data1 >> 16) & 0x00ff),
-                descriptorId = (ushort)(data1 >> 24),
+                descriptorId = (ushort)(data1 >> 16),
                 ID = (ushort)(data2 & 0xffff)
             };
         }

nanoFramework.Device.Bluetooth/GenericAttributeProfile/GattLocalCharacteristic.cs

@@ -19,6 +19,7 @@ public sealed class GattLocalCharacteristic
         // Each Characteristic will have unique _CharacteristicId for event lookup
         internal ushort _characteristicId;
 
+        private ushort _descriptorNextID;
         private readonly byte[] _characteristicUuid;
         private readonly GattProtectionLevel _writeProtectionLevel;
         private readonly GattProtectionLevel _readProtectionLevel;
@@ -71,6 +72,8 @@ internal GattLocalCharacteristic(Guid characteristicUuid, GattLocalCharacteristi
 
             // Give it next id
             _characteristicId = NextCharacteristicIndex();
+            // Start at 1 for descriptors
+            _descriptorNextID = 1;
 
             _userDescription = parameters.UserDescription;
             if (!string.IsNullOrEmpty(_userDescription))
@@ -82,7 +85,7 @@ internal GattLocalCharacteristic(Guid characteristicUuid, GattLocalCharacteristi
                 dr.WriteString(_userDescription);
                 dp.StaticValue = dr.DetachBuffer();
 
-                _userDescriptionDescriptor = new GattLocalDescriptor(GattDescriptorUuids.CharacteristicUserDescription, dp, this);
+                _userDescriptionDescriptor = new GattLocalDescriptor(GattDescriptorUuids.CharacteristicUserDescription, dp, this, _descriptorNextID++);
             }
 
             _presentationFormats = new ArrayList();
@@ -103,7 +106,7 @@ internal GattLocalCharacteristic(Guid characteristicUuid, GattLocalCharacteristi
                 GattLocalDescriptorParameters dp = new GattLocalDescriptorParameters();
                 dp.StaticValue = dr.DetachBuffer();
 
-                _presentationFormatsDescriptors.Add(new GattLocalDescriptor(GattDescriptorUuids.CharacteristicPresentationFormat, dp, this));
+                _presentationFormatsDescriptors.Add(new GattLocalDescriptor(GattDescriptorUuids.CharacteristicPresentationFormat, dp, this, _descriptorNextID++));
             }
 
             // Register with Events
@@ -147,8 +150,8 @@ public GattLocalDescriptorResult CreateDescriptor(Guid descriptorUuid, GattLocal
 
             if (result == BluetoothError.Success)
             {
-                decriptor = new GattLocalDescriptor(descriptorUuid, parameters, this);
-                _descriptors.Add(new GattLocalDescriptor(descriptorUuid, parameters, this));
+                decriptor = new GattLocalDescriptor(descriptorUuid, parameters, this, _descriptorNextID++);
+                _descriptors.Add(decriptor);
             }
 
             return new GattLocalDescriptorResult(decriptor, result);
@@ -262,15 +265,16 @@ internal void OnReadRequested(ushort descritorId, GattReadRequestedEventArgs e)
             bool handled = false;
 
             // Static value for Characteristic ?
-            if (_staticValue != null && descritorId == 0)
+            int descritorIndex = (descritorId >> 8);
+            if (_staticValue != null && descritorIndex == 0)
             {
                 handled = true;
                 // Handle static values internally, don't fire an event
                 DataWriter writer = new DataWriter();
                 writer.WriteBuffer(_staticValue);
                 e.GetRequest().RespondWithValue(_staticValue);
             }
-            else if (descritorId != 0)
+            else if (descritorIndex != 0)
             {
                 // Descriptor event, let descriptor handle it
                 GattLocalDescriptor des = FindDescriptor(descritorId);
@@ -299,8 +303,10 @@ internal void OnWriteRequested(ushort descritorId, GattWriteRequestedEventArgs e
 
             if (WriteRequested != null)
             {
+                int descritorIndex = (descritorId >> 8);  
+
                 // LocalCharacteristic event ?
-                if (descritorId == 0)
+                if (descritorIndex == 0)
                 {
                     handled = true;
                     WriteRequested?.Invoke(this, e);

nanoFramework.Device.Bluetooth/GenericAttributeProfile/GattLocalDescriptor.cs

@@ -12,8 +12,6 @@ namespace nanoFramework.Device.Bluetooth.GenericAttributeProfile
     /// </summary>
     public sealed class GattLocalDescriptor
     {
-        private static ushort GattLocalDescriptorIndex = 0;
-
         // Each Descriptor will have unique _descriptorId for event lookup, events for descriptors are handled by User app.
         // This comprises of characteristic ID + GattLocalDescriptorIndex in the form
         // x'DDCC' where DD is Descriptor and CC characteristic
@@ -41,7 +39,7 @@ public sealed class GattLocalDescriptor
         /// <param name="WriteRequestEventArgs">Event arguments</param>
         public delegate void GattLocalDescriptorWriteEventHandler(GattLocalCharacteristic sender, GattWriteRequestedEventArgs WriteRequestEventArgs);
 
-        internal GattLocalDescriptor(Guid uuid, GattLocalDescriptorParameters parameters, GattLocalCharacteristic charactisic)
+        internal GattLocalDescriptor(Guid uuid, GattLocalDescriptorParameters parameters, GattLocalCharacteristic charactisic, int descriptorIndex)
         {
             _uuid = uuid.ToByteArray();
             _charactisic = charactisic;
@@ -50,12 +48,7 @@ internal GattLocalDescriptor(Guid uuid, GattLocalDescriptorParameters parameters
             _readProtectionLevel = parameters.ReadProtectionLevel;
             _staticValue = parameters.StaticValue;
 
-            _descriptorId = (ushort)((NextDescriptorIndex() << 8) + _charactisic._characteristicId);
-        }
-
-        private static ushort NextDescriptorIndex()
-        {
-            return ++GattLocalDescriptorIndex;
+            _descriptorId = (ushort)((descriptorIndex << 8) + _charactisic._characteristicId);
         }
 
         /// <summary>

nanoFramework.Device.Bluetooth/Properties/AssemblyInfo.cs

@@ -17,7 +17,7 @@
 
 ////////////////////////////////////////////////////////////////
 // update this whenever the native assembly signature changes //
-[assembly: AssemblyNativeVersion("100.0.0.2")]
+[assembly: AssemblyNativeVersion("100.0.0.3")]
 ////////////////////////////////////////////////////////////////