private HidDeviceData ReadData(int timeout)
{
var buffer = new byte[] { };
var status = HidDeviceData.ReadStatus.NoDataRead;
if (_deviceCapabilities.InputReportByteLength > 0)
{
uint bytesRead = 0;
buffer = CreateInputBuffer();
if (_deviceReadMode == DeviceMode.Overlapped)
{
var security = new NativeMethods.SECURITY_ATTRIBUTES();
var overlapped = new NativeOverlapped();
var overlapTimeout = timeout <= 0 ? NativeMethods.WAIT_INFINITE : timeout;
security.lpSecurityDescriptor = IntPtr.Zero;
security.bInheritHandle = true;
security.nLength = Marshal.SizeOf(security);
overlapped.OffsetLow = 0;
overlapped.OffsetHigh = 0;
overlapped.EventHandle = NativeMethods.CreateEvent(ref security, Convert.ToInt32(false), Convert.ToInt32(true), string.Empty);
try
{
NativeMethods.ReadFile(ReadHandle, buffer, (uint)buffer.Length, out bytesRead, ref overlapped);
var result = NativeMethods.WaitForSingleObject(overlapped.EventHandle, overlapTimeout);
switch (result)
{
case NativeMethods.WAIT_OBJECT_0: status = HidDeviceData.ReadStatus.Success; break;
case NativeMethods.WAIT_TIMEOUT:
status = HidDeviceData.ReadStatus.WaitTimedOut;
buffer = new byte[] {};
break;
case NativeMethods.WAIT_FAILED:
status = HidDeviceData.ReadStatus.WaitFail;
buffer = new byte[] { };
break;
default:
status = HidDeviceData.ReadStatus.NoDataRead;
buffer = new byte[] { };
break;
}
}
catch { status = HidDeviceData.ReadStatus.ReadError; }
finally { CloseDeviceIO(overlapped.EventHandle); }
}
else
{
try
{
var overlapped = new NativeOverlapped();
NativeMethods.ReadFile(ReadHandle, buffer, (uint)buffer.Length, out bytesRead, ref overlapped);
status = HidDeviceData.ReadStatus.Success;
}
catch { status = HidDeviceData.ReadStatus.ReadError; }
}
}
return new HidDeviceData(buffer, status);
}
private bool WriteData(byte[] data, int timeout)
{
if (_deviceCapabilities.OutputReportByteLength <= 0) return false;
var buffer = CreateOutputBuffer();
uint bytesWritten = 0;
Array.Copy(data, 0, buffer, 0, Math.Min(data.Length, _deviceCapabilities.OutputReportByteLength));
if (_deviceWriteMode == DeviceMode.Overlapped)
{
var security = new NativeMethods.SECURITY_ATTRIBUTES();
var overlapped = new NativeOverlapped();
var overlapTimeout = timeout <= 0 ? NativeMethods.WAIT_INFINITE : timeout;
security.lpSecurityDescriptor = IntPtr.Zero;
security.bInheritHandle = true;
security.nLength = Marshal.SizeOf(security);
overlapped.OffsetLow = 0;
overlapped.OffsetHigh = 0;
overlapped.EventHandle = NativeMethods.CreateEvent(ref security, Convert.ToInt32(false), Convert.ToInt32(true), "");
try
{
NativeMethods.WriteFile(WriteHandle, buffer, (uint)buffer.Length, out bytesWritten, ref overlapped);
}
catch { return false; }
var result = NativeMethods.WaitForSingleObject(overlapped.EventHandle, overlapTimeout);
switch (result)
{
case NativeMethods.WAIT_OBJECT_0:
return true;
case NativeMethods.WAIT_TIMEOUT:
return false;
case NativeMethods.WAIT_FAILED:
return false;
default:
return false;
}
}
else
{
try
{
var overlapped = new NativeOverlapped();
return NativeMethods.WriteFile(WriteHandle, buffer, (uint)buffer.Length, out bytesWritten, ref overlapped);
}
catch { return false; }
}
}
private static IntPtr OpenDeviceIO(string devicePath, DeviceMode deviceMode, uint deviceAccess)
{
var security = new NativeMethods.SECURITY_ATTRIBUTES();
var flags = 0;
if (deviceMode == DeviceMode.Overlapped) flags = NativeMethods.FILE_FLAG_OVERLAPPED;
security.lpSecurityDescriptor = IntPtr.Zero;
security.bInheritHandle = true;
security.nLength = Marshal.SizeOf(security);
return NativeMethods.CreateFile(devicePath, deviceAccess, NativeMethods.FILE_SHARE_READ | NativeMethods.FILE_SHARE_WRITE, ref security, NativeMethods.OPEN_EXISTING, flags, 0);
}