internal static extern MMResult waveOutWrite(IntPtr hWaveOut, WaveHdr lpWaveOutHdr, int uSize);
internal static extern MMResult waveOutUnprepareHeader(IntPtr hWaveOut, WaveHdr lpWaveOutHdr, int uSize);
/// <summary>
/// Initializes the buffer.
/// </summary>
public void Initialize()
{
_buffer = new byte[_bufferSize];
var header = new WaveHdr();
_headerHandle = GCHandle.Alloc(header);
_userDataHandle = GCHandle.Alloc(this);
_bufferHandle = GCHandle.Alloc(_buffer, GCHandleType.Pinned);
header.dwUser = (IntPtr) _userDataHandle;
header.dwLoops = 1;
header.lpData = _bufferHandle.AddrOfPinnedObject();
header.dwBufferLength = _bufferSize;
_header = header;
lock (_waveOut.LockObj)
{
WaveOutResult.Try(MMInterops.waveOutPrepareHeader(_waveOut.WaveOutHandle, header,
Marshal.SizeOf(header)));
}
}
/// <summary>
/// Callback func.
/// </summary>
/// <param name="handle">The WaveOutHandle.</param>
/// <param name="msg">The WaveMessage.</param>
/// <param name="user">The UserData.</param>
/// <param name="header">The WaveHdr.</param>
/// <param name="reserved">Reserved.</param>
private void Callback(IntPtr handle, WaveMessage msg, UIntPtr user, WaveHdr header, UIntPtr reserved)
{
if (WaveOutHandle != handle)
return;
if (msg == WaveMessage.WOM_DONE)
{
var hBuffer = (GCHandle) header.dwUser;
var buffer = hBuffer.Target as WaveOutBuffer;
Interlocked.Decrement(ref _activeBuffers);
if (buffer == null) return;
if (_playbackState != PlaybackState.Stopped)
{
lock (_lockObj)
{
if (buffer.WriteData())
Interlocked.Increment(ref _activeBuffers);
}
}
if (_activeBuffers == 0)
{
_playbackState = PlaybackState.Stopped;
RaisePlaybackChanged();
}
}
else if (msg == WaveMessage.WOM_CLOSE)
{
_playbackState = PlaybackState.Stopped;
RaisePlaybackChanged();
}
}
/// <summary>
/// Disposes the object.
/// </summary>
/// <param name="disposing">The disposing state.</param>
public virtual void Dispose(bool disposing)
{
lock (_waveOut.LockObj)
{
if (_header == null || _waveOut.WaveOutHandle == IntPtr.Zero)
return;
if (_bufferHandle.IsAllocated)
_bufferHandle.Free();
if (_headerHandle.IsAllocated)
_headerHandle.Free();
if (_userDataHandle.IsAllocated)
_userDataHandle.Free();
WaveOutResult.Try(MMInterops.waveOutUnprepareHeader(_waveOut.WaveOutHandle, _header,
Marshal.SizeOf(_header)));
_header = null;
}
if (disposing)
{
}
}
