MMRESULT
StopNote(
DeviceInfo* device_info,
UCHAR note)
{
HANDLE heap = GetProcessHeap();
NoteNode* node;
NoteNode* prev_node = NULL;
DPRINT("StopNote\n");
EnterCriticalSection(&device_lock);
node = device_info->note_list;
while ( node != NULL )
{
if ( node->note == note )
{
/* Found the note - just remove the node from the list */
DPRINT("Stopping note %d\n", (int) node->note);
if ( prev_node != NULL )
prev_node->next = node->next;
else
device_info->note_list = node->next;
HeapFree(heap, 0, node);
device_info->playing_notes_count --;
DPRINT("Note stopped - now playing %d notes\n", (int) device_info->playing_notes_count);
#ifdef CONTINUOUS_NOTES
if (device_info->playing_notes_count == 0)
ResetEvent(device_info->work_available);
#endif
LeaveCriticalSection(&device_lock);
device_info->refresh_notes = TRUE;
return MMSYSERR_NOERROR;
}
prev_node = node;
node = node->next;
}
LeaveCriticalSection(&device_lock);
/* Hmm, a good idea? */
#ifndef CONTINUOUS_NOTES
ProcessPlayingNotes((PVOID) device_info);
#endif
return MMSYSERR_NOERROR;
}
MMRESULT
PlayNote(
DeviceInfo* device_info,
UCHAR note,
UCHAR velocity)
{
HANDLE heap = GetProcessHeap();
NoteNode* node;
DPRINT("PlayNote\n");
if ( velocity == 0 )
{
DPRINT("Zero velocity\n");
/* Velocity zero is effectively a "note off" */
StopNote(device_info, note);
}
else
{
/* Start playing the note */
NoteNode* new_node;
EnterCriticalSection(&device_lock);
node = device_info->note_list;
while ( node != NULL )
{
#ifndef ALLOW_DUPLICATE_NOTES
if ( ( node->note == note ) && ( velocity > 0 ) )
{
/* The note is already playing - do nothing */
DPRINT("Duplicate note playback request ignored\n");
LeaveCriticalSection(&device_lock);
return MMSYSERR_NOERROR;
}
#endif
node = node->next;
}
new_node = HeapAlloc(heap, HEAP_ZERO_MEMORY, sizeof(NoteNode));
if ( ! new_node )
{
LeaveCriticalSection(&device_lock);
return MMSYSERR_NOMEM;
}
new_node->note = note;
new_node->velocity = velocity;
/*
Prepend to the playing notes list. If exceeding polyphony,
remove the oldest note (which will be at the tail.)
*/
if ( device_info->note_list )
device_info->note_list->previous = new_node;
new_node->next = device_info->note_list;
new_node->previous = NULL;
device_info->note_list = new_node;
device_info->playing_notes_count ++;
/*
if ( device_info->playing_notes_count > POLYPHONY )
{
ASSERT(tail_node);
DPRINT("Polyphony exceeded\n");
tail_node->previous->next = NULL;
HeapFree(heap, 0, tail_node);
device_info->playing_notes_count --;
}
*/
LeaveCriticalSection(&device_lock);
DPRINT("Note started - now playing %d notes\n", (int) device_info->playing_notes_count);
device_info->refresh_notes = TRUE;
}
#ifndef CONTINUOUS_NOTES
ProcessPlayingNotes((PVOID) device_info);
#endif
return MMSYSERR_NOERROR;
}
