midi.h

/*
 * A simple MIDI parsing library
 *
 * Copyright (C) 2014-2018 Mateusz Viste
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include <stdio.h>

#ifndef midi_h_sentinel
#define midi_h_sentinel

#define MIDI_OUTOFMEM -10
#define MIDI_EMPTYTRACK -1
#define MIDI_TRACKERROR -2

enum midi_midievents {
  EVENT_NOTEOFF = 0,
  EVENT_NOTEON = 1,
  EVENT_TEMPO = 2,
  EVENT_RAW = 3,
  EVENT_PROGCHAN = 4,
  EVENT_PITCH = 5,
  EVENT_CONTROL = 6,
  EVENT_KEYPRESSURE = 7,
  EVENT_CHANPRESSURE = 8,
  EVENT_SYSEX = 9,
  EVENT_NONE = 100
};

struct midi_chunk_t {
  char id[5];
  unsigned long datalen;
  unsigned char data[1];
};

struct midi_chunkmap_t {
  long offset;
  long len;
  char id[5];
};

struct midi_event_note_t {
  unsigned char note;
  unsigned char chan;
  unsigned char velocity;
};

struct midi_event_prog_t {
  unsigned char prog;
  unsigned char chan;
};

struct midi_event_pitch_t {
  unsigned short wheel;
  unsigned char chan;
};

struct midi_event_control_t {
  unsigned char id;
  unsigned char chan;
  unsigned char val;
};

struct midi_event_chanpressure_t {
  unsigned char chan;
  unsigned char pressure;
};

struct midi_event_keypressure_t {
  unsigned char chan;
  unsigned char note;
  unsigned char pressure;
};

struct midi_event_sysex_t {
  long sysexptr;
};

struct midi_event_t {
  long next;
  unsigned long deltatime;
  union {
    struct midi_event_note_t note;
    struct midi_event_prog_t prog;
    struct midi_event_pitch_t pitch;
    struct midi_event_control_t control;
    struct midi_event_chanpressure_t chanpressure;
    struct midi_event_keypressure_t keypressure;
    struct midi_event_sysex_t sysex;
    unsigned long tempoval;
  } data;
  enum midi_midievents type;
};

struct midi_chunk_t *midi_readchunk(FILE *fd);

int midi_readhdr(FILE *fd, int *format, int *tracks, unsigned short *timeunitdiv, struct midi_chunkmap_t *chunklist, int maxchunks);

/* parse a track object and returns the id of the first events in the linked list */
long midi_track2events(FILE *fd, char *title, int titlemaxlen, char *copyright, int copyrightmaxlen, char *text, int textmaxlen, unsigned short *channelsusage, FILE *logfd, unsigned long *tracklen);

/* merge two MIDI tracks into a single (serialized) one. returns a "pointer"
 * to the unique track. I take care not to allocate/free memory here.
 * All notes are already in RAM after all. totlen is filled with the total
 * time of the merged tracks (in miliseconds). */
long midi_mergetrack(long t0, long t1, unsigned long *totlen, unsigned short timeunitdiv);

#endif