midi.h

   1 /*
   2 Calf Box, an open source musical instrument.
   3 Copyright (C) 2010-2013 Krzysztof Foltman
   4
   5 This program is free software: you can redistribute it and/or modify
   6 it under the terms of the GNU General Public License as published by
   7 the Free Software Foundation, either version 3 of the License, or
   8 (at your option) any later version.
   9
  10 This program is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU General Public License for more details.
  14
  15 You should have received a copy of the GNU General Public License
  16 along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17 */
  18
  19 #ifndef CBOX_MIDI_H
  20 #define CBOX_MIDI_H
  21
  22 #include <ctype.h>
  23 #include <stdint.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26
  27 struct cbox_midi_event
  28 {
  29     uint32_t time;
  30     uint32_t size;
  31     union {
  32         uint8_t data_inline[4]; /* up to 4 bytes */
  33         uint8_t *data_ext; /* if larger than 4 bytes */
  34     };
  35 };
  36
  37 #define CBOX_MIDI_MAX_EVENTS 256
  38 #define CBOX_MIDI_MAX_LONG_DATA 256
  39
  40 struct cbox_midi_buffer
  41 {
  42     uint32_t count;
  43     uint32_t long_data_size;
  44     struct cbox_midi_event events[CBOX_MIDI_MAX_EVENTS];
  45     uint8_t long_data[CBOX_MIDI_MAX_LONG_DATA];
  46 };
  47
  48 static inline void cbox_midi_buffer_init(struct cbox_midi_buffer *buffer)
  49 {
  50     buffer->count = 0;
  51     buffer->long_data_size = 0;
  52 }
  53
  54 static inline void cbox_midi_buffer_clear(struct cbox_midi_buffer *buffer)
  55 {
  56     buffer->count = 0;
  57     buffer->long_data_size = 0;
  58 }
  59
  60 static inline void cbox_midi_buffer_copy(struct cbox_midi_buffer *dst, const struct cbox_midi_buffer *src)
  61 {
  62     dst->count = src->count;
  63     dst->long_data_size = src->long_data_size;
  64     memcpy(dst->events, src->events, src->count * sizeof(struct cbox_midi_event));
  65     memcpy(dst->long_data, src->long_data, src->long_data_size);
  66     // for any long events, update data pointers
  67     for (int i = 0; i < src->count; i++)
  68     {
  69         if (dst->events[i].size > 4)
  70             dst->events[i].data_ext += &dst->long_data[0] - &src->long_data[0];
  71     }
  72 }
  73
  74 static inline uint32_t cbox_midi_buffer_get_count(struct cbox_midi_buffer *buffer)
  75 {
  76     return buffer->count;
  77 }
  78
  79 static inline uint32_t cbox_midi_buffer_get_last_event_time(struct cbox_midi_buffer *buffer)
  80 {
  81     if (!buffer->count)
  82         return 0;
  83     return buffer->events[buffer->count - 1].time;
  84 }
  85
  86 static inline int cbox_midi_buffer_can_store_msg(struct cbox_midi_buffer *buffer, int size)
  87 {
  88     if (buffer->count >= CBOX_MIDI_MAX_EVENTS)
  89         return 0;
  90     if (size < 4)
  91         return 1;
  92     return buffer->long_data_size + size <= CBOX_MIDI_MAX_LONG_DATA;
  93 }
  94
  95 static inline const struct cbox_midi_event *cbox_midi_buffer_get_event(const struct cbox_midi_buffer *buffer, uint32_t pos)
  96 {
  97     if (pos >= buffer->count)
  98         return NULL;
  99     return &buffer->events[pos];
 100 }
 101
 102 static inline const uint8_t *cbox_midi_event_get_data(const struct cbox_midi_event *evt)
 103 {
 104     return evt->size > 4 ? evt->data_ext : evt->data_inline;
 105 }
 106
 107 static inline int midi_cmd_size(uint8_t cmd)
 108 {
 109     static const int sizes[] = { 3, 3, 3, 3, 2, 2, 3, 1 };
 110     if (cmd < 128)
 111         return 0;
 112     return sizes[(cmd >> 4) - 8];
 113 }
 114
 115 extern int cbox_midi_buffer_write_event(struct cbox_midi_buffer *buffer, uint32_t time, uint8_t *data, uint32_t size);
 116
 117 extern int cbox_midi_buffer_write_inline(struct cbox_midi_buffer *buffer, uint32_t time, ...);
 118
 119 extern int cbox_midi_buffer_copy_event(struct cbox_midi_buffer *buffer, const struct cbox_midi_event *event, int new_time);
 120
 121 extern int note_from_string(const char *note);
 122
 123 extern int cbox_config_get_note(const char *cfg_section, const char *key, int def_value);
 124
 125 #endif