private bool InitData(byte[] buffer, MIDIHDR header)
{
if (buffer == null || header == null)
{
return(false);
}
try
{
header.Reset();
header.bufferLength = buffer.Length;
header.data = Marshal.AllocHGlobal(buffer.Length);
if (header.data != IntPtr.Zero)
{
for (int i = 0; i < buffer.Length; i++)
{
Marshal.WriteByte(header.data, i, buffer[i]);
}
}
}
catch
{
header.Reset();
}
return(header.data != IntPtr.Zero);
}
private IntPtr AllocHeader(MIDIHDR header)
{
IntPtr intPtr = IntPtr.Zero;
try
{
intPtr = Marshal.AllocHGlobal(Marshal.SizeOf(typeof(MIDIHDR)));
}
catch (Exception)
{
try
{
if (header.data != IntPtr.Zero)
{
Marshal.FreeHGlobal(header.data);
}
}
catch
{
}
header.data = IntPtr.Zero;
}
try
{
Marshal.StructureToPtr(header, intPtr, true);
}
catch (Exception)
{
try
{
if (header.data != IntPtr.Zero)
{
Marshal.FreeHGlobal(header.data);
}
}
catch
{
}
header.data = IntPtr.Zero;
try
{
if (intPtr != IntPtr.Zero)
{
Marshal.FreeHGlobal(intPtr);
}
}
catch
{
}
intPtr = IntPtr.Zero;
}
return(intPtr);
}
private bool PrepareHeader(bool input, IntPtr handle, IntPtr headerPtr)
{
MIDIError midierror = MIDIError.MIDI_OK;
if (headerPtr != IntPtr.Zero)
{
if (input)
{
midierror = Midi.MIDI_InPrepareHeader(handle, headerPtr);
}
else
{
midierror = Midi.MIDI_OutPrepareHeader(handle, headerPtr);
}
}
if (midierror != MIDIError.MIDI_OK)
{
MIDIHDR midihdr = null;
try
{
midihdr = (MIDIHDR)Marshal.PtrToStructure(headerPtr, typeof(MIDIHDR));
}
catch
{
}
if (midihdr != null)
{
try
{
if (midihdr.data != IntPtr.Zero)
{
Marshal.FreeHGlobal(midihdr.data);
}
}
catch
{
}
midihdr.data = IntPtr.Zero;
try
{
if (headerPtr != IntPtr.Zero)
{
Marshal.FreeHGlobal(headerPtr);
}
}
catch
{
}
}
}
return(midierror == MIDIError.MIDI_OK);
}
private void UnprepareHeader(bool input, IntPtr handle, IntPtr headerPtr)
{
if (headerPtr == IntPtr.Zero)
{
return;
}
MIDIHDR midihdr = null;
try
{
midihdr = (MIDIHDR)Marshal.PtrToStructure(headerPtr, typeof(MIDIHDR));
}
catch
{
}
if (midihdr != null)
{
try
{
if (input)
{
Midi.MIDI_InUnprepareHeader(handle, headerPtr);
}
else
{
Midi.MIDI_OutUnprepareHeader(handle, headerPtr);
}
}
catch
{
}
try
{
if (midihdr.data != IntPtr.Zero)
{
Marshal.FreeHGlobal(midihdr.data);
}
}
catch
{
}
try
{
Marshal.FreeHGlobal(headerPtr);
}
catch
{
}
}
}
public bool Prepare(bool input, IntPtr handle)
{
if (this._headerPtr != IntPtr.Zero)
{
this.Unprepare(input, handle);
}
IntPtr headerPtr = IntPtr.Zero;
MIDIHDR header = new MIDIHDR();
if (this.InitData(this._data, header))
{
headerPtr = this.AllocHeader(header);
if (!this.PrepareHeader(input, handle, headerPtr))
{
headerPtr = IntPtr.Zero;
}
}
this._headerPtr = headerPtr;
return(this._headerPtr != IntPtr.Zero);
}
public MIDI_HEADER(IntPtr headerPtr)
{
if (headerPtr == IntPtr.Zero)
{
return;
}
this._headerPtr = headerPtr;
MIDIHDR midihdr = null;
try
{
midihdr = (MIDIHDR)Marshal.PtrToStructure(headerPtr, typeof(MIDIHDR));
}
catch
{
midihdr = null;
}
if (midihdr != null)
{
this._data = midihdr.GetData();
this._flags = midihdr.flags;
this._user = midihdr.user;
}
}
