/// <summary>
/// Creates and initializes a <see cref="LongMessage"/>, for use inside the <see cref="MidiInputDevice.Callback"/> method.
/// </summary>
/// <param name="messageParameterA">An <see cref="IntPtr"/> to store a reference to the first message parameter.</param>
/// <param name="messageParameterB">An <see cref="IntPtr"/> to store a reference to the second message parameter.</param>
internal LongMessage(IntPtr messageParameterA, IntPtr messageParameterB)
{
// Set the pointer to the MIDI header structure (Converted from UIntPtr to IntPtr)
_MidiHeaderPointer = unchecked ((IntPtr)(long)(ulong)messageParameterA);
// Create a managed copy of the MIDI header
_MidiHeader = (API.MidiHeader)Marshal.PtrToStructure(_MidiHeaderPointer, typeof(API.MidiHeader));
// Create the data array with the size of the long message
this.Data = new byte[_MidiHeader.BytesRecorded];
// Fill the data array by looping through the MIDI header data
for (int i = 0; i < _MidiHeader.BytesRecorded; i++)
{
this.Data[i] = Marshal.ReadByte(_MidiHeader.Data, i);
}
// Extract the ID byte
this.ID = this.Data[1];
// Extract message parameter B
this.TimeStamp = (int)messageParameterB;
// Set the parameter references
this.ParameterA = messageParameterA;
this.ParameterB = messageParameterB;
}
private void Dispose(bool disposing)
{
if (!_IsDisposed)
{
if (disposing)
{
// TODO: dispose managed state (managed objects)
}
if (_Buffer.Count > 0)
{
API.ResetMidiInputDevice(_Handle);
foreach (var headerPointer in _Buffer)
{
API.MidiHeader header = (API.MidiHeader)Marshal.PtrToStructure(headerPointer, typeof(API.MidiHeader));
API.UnprepareMidiInputHeader(_Handle, headerPointer, Marshal.SizeOf(typeof(API.MidiHeader)));
Marshal.FreeHGlobal(header.Data);
Marshal.FreeHGlobal(headerPointer);
}
}
API.CloseMidiInputDevice(_Handle);
// TODO: free unmanaged resources (unmanaged objects) and override finalizer
// TODO: set large fields to null
_IsDisposed = true;
}
}
/// <summary>
/// Callback function to be called by the system.
/// </summary>
/// <param name="handle">An <see cref="API.MidiDeviceHandle"/> to the MIDI input device to associate with the callback function.</param>
/// <param name="message">An <see cref="API.MidiInputMessage"/> containing the message.</param>
/// <param name="instance">An <see cref="IntPtr"/> to the instance data supplied by the <see cref="API.OpenMidiInputDevice"/> function.</param>
/// <param name="messageParameterA">An <see cref="IntPtr"/> to the first message parameter.</param>
/// <param name="messageParameterB">An <see cref="IntPtr"/> to the second message parameter.</param>
private void Callback(API.MidiDeviceHandle handle, API.MidiInputMessage message, IntPtr instance, IntPtr messageParameterA, IntPtr messageParameterB)
{
switch (message)
{
case API.MidiInputMessage.MIDI_INPUT_MESSAGE_DATA:
// A = Packed MIDI message, B = Time in milliseconds since Start
ProcessShortMessage(new ShortMessage(messageParameterA, messageParameterB));
break;
case API.MidiInputMessage.MIDI_INPUT_MESSAGE_LONG_DATA:
// Extracts the MIDI header for message validation
API.MidiHeader midiHeader = (API.MidiHeader)Marshal.PtrToStructure(messageParameterA, typeof(API.MidiHeader));
// Prevents creation of long messages when the MIDI header buffer is empty
if (midiHeader.BytesRecorded == 0)
{
ReleaseBuffer(messageParameterA);
return;
}
// A = Pointer to MIDI header, B = Time in milliseconds since Start
ProcessLongMessage(new LongMessage(messageParameterA, messageParameterB));
break;
case API.MidiInputMessage.MIDI_INPUT_MESSAGE_MORE_DATA:
Console.WriteLine("MIDI IN MORE DATA");
// A = Packed MIDI message, B = Time in milliseconds since Start
break;
case API.MidiInputMessage.MIDI_INPUT_MESSAGE_ERROR:
// A = Invalid MIDI message, B = Time in milliseconds since Start
break;
case API.MidiInputMessage.MIDI_INPUT_MESSAGE_LONG_ERROR:
// A = Pointer to MIDI header, B = Time in milliseconds since Start
break;
case API.MidiInputMessage.MIDI_INPUT_MESSAGE_OPEN:
this.IsOpen = true;
break;
case API.MidiInputMessage.MIDI_INPUT_MESSAGE_CLOSE:
this.IsOpen = false;
break;
}
}
/// <summary>
/// Releases an existing buffer and associated memory.
/// </summary>
/// <param name="buffer">An <see cref="IntPtr"/> referencing the buffer to release.</param>
/// <exception cref="MidiInputDeviceException">Raises <see cref="API.Result.MULTIMEDIA_SYSTEM_ERROR_INVALID_HANDLE"/>.</exception>
/// <exception cref="MidiInputDeviceException">Raises <see cref="API.Result.MULTIMEDIA_SYSTEM_ERROR_INVALID_PARAMETER"/>.</exception>
/// <exception cref="MidiInputDeviceException">Raises <see cref="API.Result.MIDI_ERROR_STILL_PLAYING"/>.</exception>
private void ReleaseBuffer(IntPtr buffer)
{
IntPtr headerPointer = unchecked ((IntPtr)(long)(ulong)buffer);
int headerSize = Marshal.SizeOf(typeof(API.MidiHeader));
InvalidateResult(API.UnprepareMidiInputHeader(_Handle, headerPointer, headerSize));
API.MidiHeader midiHeader = (API.MidiHeader)Marshal.PtrToStructure(headerPointer, typeof(API.MidiHeader));
Marshal.FreeHGlobal(midiHeader.Data);
Marshal.FreeHGlobal(headerPointer);
_Buffer.Remove(headerPointer);
}
/// <summary>
/// Sends a long MIDI message.
/// </summary>
/// <param name="message">The long MIDI message to send.</param>
/// <exception cref="MidiOutputDeviceException">Raises <see cref="API.Result.MULTIMEDIA_SYSTEM_ERROR_INVALID_HANDLE"/>.</exception>
/// <exception cref="MidiOutputDeviceException">Raises <see cref="API.Result.MULTIMEDIA_SYSTEM_ERROR_NO_MEM"/>.</exception>
/// <exception cref="MidiOutputDeviceException">Raises <see cref="API.Result.MULTIMEDIA_SYSTEM_ERROR_INVALID_PARAMETER"/>.</exception>
/// <exception cref="MidiOutputDeviceException">Raises <see cref="API.Result.MIDI_ERROR_UNPREPARED"/>.</exception>
/// <exception cref="MidiOutputDeviceException">Raises <see cref="API.Result.MIDI_ERROR_STILL_PLAYING"/>.</exception>
/// <exception cref="MidiOutputDeviceException">Raises <see cref="API.Result.MIDI_ERROR_NOT_READY"/>.</exception>
public void Send(LongMessage message)
{
IntPtr midiHeaderPointer;
int midiHeaderSize = Marshal.SizeOf(typeof(API.MidiHeader));
API.MidiHeader midiHeader = new API.MidiHeader();
midiHeader.Data = Marshal.AllocHGlobal(message.Data.Length);
for (int i = 0; i < message.Data.Length; i++)
{
Marshal.WriteByte(midiHeader.Data, i, message.Data[i]);
}
midiHeader.BufferSize = message.Data.Length;
midiHeader.BytesRecorded = message.Data.Length;
midiHeader.Flags = 0;
try
{
midiHeaderPointer = Marshal.AllocHGlobal(Marshal.SizeOf(typeof(API.MidiHeader)));
}
catch (Exception)
{
Marshal.FreeHGlobal(midiHeader.Data);
throw;
}
try
{
Marshal.StructureToPtr(midiHeader, midiHeaderPointer, false);
}
catch (Exception)
{
Marshal.FreeHGlobal(midiHeader.Data);
Marshal.FreeHGlobal(midiHeaderPointer);
throw;
}
InvalidateResult(API.PrepareMidiOutputHeader(_Handle, midiHeaderPointer, midiHeaderSize));
InvalidateResult(API.SendLongMessage(_Handle, midiHeaderPointer, midiHeaderSize));
InvalidateResult(API.UnprepareMidiOutputHeader(_Handle, midiHeaderPointer, midiHeaderSize));
Marshal.FreeHGlobal(midiHeader.Data);
Marshal.FreeHGlobal(midiHeaderPointer);
}
/// <summary>
/// Creates a buffer for receiving <see cref="LongMessage"/>s.
/// </summary>
/// <returns>An <see cref="IntPtr"/> referencing the created buffer.</returns>
/// <exception cref="MidiInputDeviceException">Raises <see cref="API.Result.MULTIMEDIA_SYSTEM_ERROR_INVALID_HANDLE"/>.</exception>
/// <exception cref="MidiInputDeviceException">Raises <see cref="API.Result.MULTIMEDIA_SYSTEM_ERROR_NO_MEM"/>.</exception>
/// <exception cref="MidiInputDeviceException">Raises <see cref="API.Result.MULTIMEDIA_SYSTEM_ERROR_INVALID_PARAMETER"/>.</exception>
/// <exception cref="MidiInputDeviceException">Raises <see cref="API.Result.MIDI_ERROR_UNPREPARED"/>.</exception>
/// <exception cref="MidiInputDeviceException">Raises <see cref="API.Result.MIDI_ERROR_STILL_PLAYING"/>.</exception>
private IntPtr CreateBuffer()
{
IntPtr midiHeaderPointer;
int headerSize = Marshal.SizeOf(typeof(API.MidiHeader));
API.MidiHeader midiHeader = new API.MidiHeader();
// TODO: Optimize buffer size
midiHeader.Data = Marshal.AllocHGlobal(256);
midiHeader.BufferSize = 256;
midiHeader.Flags = 0;
try
{
midiHeaderPointer = Marshal.AllocHGlobal(Marshal.SizeOf(typeof(API.MidiHeader)));
}
catch (Exception)
{
Marshal.FreeHGlobal(midiHeader.Data);
throw;
}
try
{
Marshal.StructureToPtr(midiHeader, midiHeaderPointer, false);
}
catch (Exception)
{
Marshal.FreeHGlobal(midiHeader.Data);
Marshal.FreeHGlobal(midiHeaderPointer);
throw;
}
InvalidateResult(API.PrepareMidiInputHeader(_Handle, midiHeaderPointer, headerSize));
InvalidateResult(API.AddMidiInputBuffer(_Handle, midiHeaderPointer, headerSize));
return(midiHeaderPointer);
}
