Merge branch 'master' into phantom

1 files changed, 67 insertions, 0 deletions

diff --git a/audio/softsynth/mt32/MidiEventQueue.h b/audio/softsynth/mt32/MidiEventQueue.h
new file mode 100644
index 0000000000..b1948c5f8e
--- /dev/null
+++ b/audio/softsynth/mt32/MidiEventQueue.h
@@ -0,0 +1,67 @@
+/* Copyright (C) 2003, 2004, 2005, 2006, 2008, 2009 Dean Beeler, Jerome Fisher
+ * Copyright (C) 2011, 2012, 2013, 2014 Dean Beeler, Jerome Fisher, Sergey V. Mikayev
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU Lesser General Public License as published by
+ *  the Free Software Foundation, either version 2.1 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU Lesser General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Lesser General Public License
+ *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef MT32EMU_MIDI_EVENT_QUEUE_H
+#define MT32EMU_MIDI_EVENT_QUEUE_H
+
+namespace MT32Emu {
+
+/**
+ * Used to safely store timestamped MIDI events in a local queue.
+ */
+struct MidiEvent {
+	Bit32u shortMessageData;
+	const Bit8u *sysexData;
+	Bit32u sysexLength;
+	Bit32u timestamp;
+
+	~MidiEvent();
+	void setShortMessage(Bit32u shortMessageData, Bit32u timestamp);
+	void setSysex(const Bit8u *sysexData, Bit32u sysexLength, Bit32u timestamp);
+};
+
+/**
+ * Simple queue implementation using a ring buffer to store incoming MIDI event before the synth actually processes it.
+ * It is intended to:
+ * - get rid of prerenderer while retaining graceful partial abortion
+ * - add fair emulation of the MIDI interface delays
+ * - extend the synth interface with the default implementation of a typical rendering loop.
+ * THREAD SAFETY:
+ * It is safe to use either in a single thread environment or when there are only two threads - one performs only reading
+ * and one performs only writing. More complicated usage requires external synchronisation.
+ */
+class MidiEventQueue {
+private:
+	MidiEvent * const ringBuffer;
+	const Bit32u ringBufferMask;
+	volatile Bit32u startPosition;
+	volatile Bit32u endPosition;
+
+public:
+	MidiEventQueue(Bit32u ringBufferSize = DEFAULT_MIDI_EVENT_QUEUE_SIZE); // Must be a power of 2
+	~MidiEventQueue();
+	void reset();
+	bool pushShortMessage(Bit32u shortMessageData, Bit32u timestamp);
+	bool pushSysex(const Bit8u *sysexData, Bit32u sysexLength, Bit32u timestamp);
+	const MidiEvent *peekMidiEvent();
+	void dropMidiEvent();
+	bool isFull() const;
+};
+
+}
+
+#endif