EventRingBuffer.hpp

/* This file is part of Raul.
 * Copyright (C) 2007-2009 David Robillard <http://drobilla.net>
 *
 * Raul is free software; you can redistribute it and/or modify it under the
 * terms of the GNU General Public License as published by the Free Software
 * Foundation; either version 2 of the License, or (at your option) any later
 * version.
 *
 * Raul 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 General Public License for details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
 */

#ifndef RAUL_EVENT_RING_BUFFER_HPP
#define RAUL_EVENT_RING_BUFFER_HPP

#include <cassert>
#include <algorithm>
#include "raul/RingBuffer.hpp"
#include "raul/TimeStamp.hpp"

namespace Raul {


class EventRingBuffer : private Raul::RingBuffer {
public:

    explicit EventRingBuffer(size_t capacity)
        : RingBuffer(capacity)
    {}

    size_t capacity() const { return _size; }

    size_t write(TimeStamp time, size_t size, const uint8_t* buf);
    bool   read(TimeStamp* time, size_t* size, uint8_t* buf);
};


inline bool
EventRingBuffer::read(TimeStamp* time, size_t* size, uint8_t* buf)
{
    bool success = RingBuffer::full_read(sizeof(TimeStamp), (uint8_t*)time);
    if (success)
        success = RingBuffer::full_read(sizeof(size_t), (uint8_t*)size);
    if (success)
        success = RingBuffer::full_read(*size, buf);

    return success;
}


inline size_t
EventRingBuffer::write(TimeStamp time, size_t size, const uint8_t* buf)
{
    assert(size > 0);

    if (write_space() < (sizeof(TimeStamp) + sizeof(size_t) + size)) {
        return 0;
    } else {
        RingBuffer::write(sizeof(TimeStamp), (uint8_t*)&time);
        RingBuffer::write(sizeof(size_t), (uint8_t*)&size);
        RingBuffer::write(size, buf);
        return size;
    }
}


} // namespace Raul

#endif // RAUL_EVENT_RING_BUFFER_HPP