MidiEventQueue.h

/* Copyright (C) 2003, 2004, 2005, 2006, 2008, 2009 Dean Beeler, Jerome Fisher
 * Copyright (C) 2011-2022 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

#include "globals.h"
#include "Types.h"

namespace MT32Emu {

class MidiEventQueue {
public:
    class SysexDataStorage;

    struct MidiEvent {
        const Bit8u *sysexData;
        union {
            Bit32u sysexLength;
            Bit32u shortMessageData;
        };
        Bit32u timestamp;
    };

    explicit MidiEventQueue(
        // Must be a power of 2
        Bit32u ringBufferSize,
        Bit32u storageBufferSize
    );
    ~MidiEventQueue();
    void reset();
    bool pushShortMessage(Bit32u shortMessageData, Bit32u timestamp);
    bool pushSysex(const Bit8u *sysexData, Bit32u sysexLength, Bit32u timestamp);
    const volatile MidiEvent *peekMidiEvent();
    void dropMidiEvent();
    inline bool isEmpty() const;

private:
    SysexDataStorage &sysexDataStorage;

    MidiEvent * const ringBuffer;
    const Bit32u ringBufferMask;
    volatile Bit32u startPosition;
    volatile Bit32u endPosition;
};

} // namespace MT32Emu

#endif // #ifndef MT32EMU_MIDI_EVENT_QUEUE_H