Releasing BLE devices on connection close

This means that you can now discoonect the session and
after reconnecting, access the devices you had connected
before the disconnect.

Fixes #170

Also added some error handling around the xbox controller
so that pulling the plug out doesn't cause an exception.

Author: blackspherefollower

Buttplug.Components.WebsocketServer/ButtplugWebsocketServer.cs

@@ -111,6 +111,7 @@ private async Task HandleConnectionAsync(WebSocket ws, CancellationToken cancell
             finally
             {
                 buttplug.MessageReceived -= msgReceived;
+                buttplug.Shutdown();
                 buttplug = null;
                 ws.Dispose();
             }

Buttplug.Core/ButtplugDevice.cs

@@ -67,5 +67,7 @@ public virtual Task<ButtplugMessage> Initialize()
             // ReSharper disable once AssignNullToNotNullAttribute
             return Task.FromResult<ButtplugMessage>(new Ok(ButtplugConsts.SystemMsgId));
         }
+
+        public abstract void Disconnect();
     }
 }

Buttplug.Core/IButtplugDevice.cs

@@ -24,5 +24,7 @@ public interface IButtplugDevice
 
         [NotNull]
         Task<ButtplugMessage> Initialize();
+
+        void Disconnect();
     }
 }

Buttplug.Server.Managers.UWPBluetoothManager/UWPBluetoothDeviceInterface.cs

@@ -15,8 +15,8 @@ internal class UWPBluetoothDeviceInterface : IBluetoothDeviceInterface
     {
         public string Name => _bleDevice.Name;
 
-        [NotNull]
-        private readonly BluetoothLEDevice _bleDevice;
+        [CanBeNull]
+        private BluetoothLEDevice _bleDevice;
         [NotNull]
         private readonly GattCharacteristic[] _gattCharacteristics;
         [NotNull]
@@ -40,7 +40,7 @@ public UWPBluetoothDeviceInterface(
 
         private void ConnectionStatusChangedHandler([NotNull] BluetoothLEDevice aDevice, [NotNull] object aObj)
         {
-            if (_bleDevice.ConnectionStatus == BluetoothConnectionStatus.Disconnected)
+            if (_bleDevice?.ConnectionStatus == BluetoothConnectionStatus.Disconnected)
             {
                 DeviceRemoved?.Invoke(this, new EventArgs());
             }
@@ -87,5 +87,17 @@ public async Task<ButtplugMessage> WriteValue(uint aMsgId,
 
             return new Ok(aMsgId);
         }
+
+        public void Disconnect()
+        {
+            DeviceRemoved?.Invoke(this, new EventArgs());
+            for (int i = 0; i < _gattCharacteristics.Length; i++)
+            {
+                _gattCharacteristics[i] = null;
+            }
+
+            _bleDevice.Dispose();
+            _bleDevice = null;
+        }
     }
 }

Buttplug.Server.Managers.XInputGamepadManager/XInputGamepadDevice.cs

@@ -1,4 +1,5 @@
-using System.Threading.Tasks;
+using System;
+using System.Threading.Tasks;
 using Buttplug.Core;
 using Buttplug.Core.Messages;
 using SharpDX.XInput;
@@ -7,7 +8,7 @@ namespace Buttplug.Server.Managers.XInputGamepadManager
 {
     internal class XInputGamepadDevice : ButtplugDevice
     {
-        private readonly Controller _device;
+        private Controller _device;
 
         public XInputGamepadDevice(IButtplugLogManager aLogManager, Controller aDevice)
             : base(aLogManager, "XBox Compatible Gamepad (XInput)", aDevice.UserIndex.ToString())
@@ -35,8 +36,43 @@ private Task<ButtplugMessage> HandleSingleMotorVibrateCmd(ButtplugDeviceMessage
                 LeftMotorSpeed = (ushort)(cmdMsg.Speed * ushort.MaxValue),
                 RightMotorSpeed = (ushort)(cmdMsg.Speed * ushort.MaxValue),
             };
-            _device.SetVibration(v);
+
+            try
+            {
+                _device?.SetVibration(v);
+            }
+            catch (Exception e)
+            {
+                if (_device?.IsConnected != true)
+                {
+                    InvokeDeviceRemoved();
+
+                    // Don't throw a spanner in the works
+                    return Task.FromResult<ButtplugMessage>(new Ok(aMsg.Id));
+                }
+
+                return Task.FromResult<ButtplugMessage>(BpLogger.LogErrorMsg(aMsg.Id, Error.ErrorClass.ERROR_DEVICE, e.Message));
+            }
+
             return Task.FromResult<ButtplugMessage>(new Ok(aMsg.Id));
         }
+
+        public override void Disconnect()
+        {
+            var v = new Vibration
+            {
+                LeftMotorSpeed = 0,
+                RightMotorSpeed = 0,
+            };
+            try
+            {
+                _device?.SetVibration(v);
+                _device = null;
+            }
+            finally
+            {
+                _device = null;
+            }
+        }
     }
 }

Buttplug.Server.Test/TestDevice.cs

@@ -1,4 +1,5 @@
-using System.Threading.Tasks;
+using System;
+using System.Threading.Tasks;
 using Buttplug.Core;
 using Buttplug.Core.Messages;
 
@@ -22,5 +23,10 @@ public void RemoveDevice()
         {
             InvokeDeviceRemoved();
         }
+
+        public override void Disconnect()
+        {
+            RemoveDevice();
+        }
     }
 }

Buttplug.Server/Bluetooth/ButtplugBluetoothDevice.cs

@@ -20,6 +20,11 @@ protected ButtplugBluetoothDevice([NotNull] IButtplugLogManager aLogManager,
             Interface.DeviceRemoved += DeviceRemovedHandler;
         }
 
+        public override void Disconnect()
+        {
+            Interface.Disconnect();
+        }
+
         private void DeviceRemovedHandler(object aObject, EventArgs aEvent)
         {
             InvokeDeviceRemoved();

Buttplug.Server/Bluetooth/IBluetoothDeviceInterface.cs

@@ -13,5 +13,7 @@ public interface IBluetoothDeviceInterface
         ulong GetAddress();
 
         event EventHandler DeviceRemoved;
+
+        void Disconnect();
     }
 }

Buttplug.Server/ButtplugService.cs

@@ -153,6 +153,11 @@ public async Task<ButtplugMessage> SendMessage([NotNull] ButtplugMessage aMsg)
             return await _deviceManager.SendMessage(aMsg);
         }
 
+        public void Shutdown()
+        {
+            _deviceManager.RemoveAllDevices();
+        }
+
         [ItemNotNull]
         public async Task<ButtplugMessage[]> SendMessage(string aJsonMsgs)
         {

Buttplug.Server/DeviceManager.cs

@@ -174,6 +174,15 @@ public async Task<ButtplugMessage> SendMessage(ButtplugMessage aMsg)
             return _bpLogger.LogErrorMsg(id, Error.ErrorClass.ERROR_MSG, $"Message type {aMsg.GetType().Name} unhandled by this server.");
         }
 
+        internal void RemoveAllDevices()
+        {
+            StopScanning();
+            foreach (var d in _devices.Values)
+            {
+                d.Disconnect();
+            }
+        }
+
         private void StartScanning()
         {
             _sentFinished = false;