2 Copyright (C) 2006 Paul Davis
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2 of the License, or
7 (at your option) any later version.
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software
16 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19 #ifndef __ardour_midi_ring_buffer_h__
20 #define __ardour_midi_ring_buffer_h__
25 #include "evoral/EventRingBuffer.hpp"
27 #include "ardour/libardour_visibility.h"
28 #include "ardour/types.h"
29 #include "ardour/midi_state_tracker.h"
35 /** A RingBuffer for (MIDI) events.
37 * This is simply a wrapper around a raw ringbuffer which writes/reads events
38 * as flat placked blobs.
39 * The buffer looks like this:
41 * [timestamp][type][size][size bytes of raw MIDI][timestamp][type][size](etc...)
44 class LIBARDOUR_API MidiRingBuffer : public Evoral::EventRingBuffer<T> {
46 /** @param size Size in bytes.
48 MidiRingBuffer(size_t size)
49 : Evoral::EventRingBuffer<T>(size) {}
51 inline bool read_prefix(T* time, Evoral::EventType* type, uint32_t* size);
52 inline bool read_contents(uint32_t size, uint8_t* buf);
54 size_t read(MidiBuffer& dst, framepos_t start, framepos_t end, framecnt_t offset=0, bool stop_on_overflow_in_destination=false);
56 void dump(std::ostream& dst);
57 void flush (framepos_t start, framepos_t end);
59 void reset_tracker ();
60 void loop_resolve (MidiBuffer& dst, framepos_t);
63 inline bool is_channel_event(uint8_t event_type_byte) {
64 // mask out channel information
65 event_type_byte &= 0xF0;
66 // midi channel events range from 0x80 to 0xE0
67 return (0x80 <= event_type_byte) && (event_type_byte <= 0xE0);
70 inline bool is_note_on(uint8_t event_type_byte) {
71 // mask out channel information
72 return (event_type_byte & 0xF0) == MIDI_CMD_NOTE_ON;
75 inline bool is_note_off(uint8_t event_type_byte) {
76 // mask out channel information
77 return (event_type_byte & 0xF0) == MIDI_CMD_NOTE_OFF;
81 MidiStateTracker _tracker;
85 /** Read the time and size of an event. This call MUST be immediately proceeded
86 * by a call to read_contents (or the read pointer will be garbage).
90 MidiRingBuffer<T>::read_prefix(T* time, Evoral::EventType* type, uint32_t* size)
92 if (PBD::RingBufferNPT<uint8_t>::read((uint8_t*)time, sizeof(T)) != sizeof (T)) {
96 if (PBD::RingBufferNPT<uint8_t>::read((uint8_t*)type, sizeof(Evoral::EventType)) != sizeof (Evoral::EventType)) {
100 if (PBD::RingBufferNPT<uint8_t>::read((uint8_t*)size, sizeof(uint32_t)) != sizeof (uint32_t)) {
108 /** Read the content of an event. This call MUST be immediately preceded
109 * by a call to read_prefix (or the returned even will be garbage).
113 MidiRingBuffer<T>::read_contents(uint32_t size, uint8_t* buf)
115 return PBD::RingBufferNPT<uint8_t>::read(buf, size) == size;
118 } // namespace ARDOUR
120 #endif // __ardour_midi_ring_buffer_h__