Jack2  1.9.9
midi_unpack.h
1 /*
2  * Copyright (c) 2006,2007 Dmitry S. Baikov
3  *
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.
8  *
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.
13  *
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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17  */
18 
19 #ifndef __jack_midi_unpack_h__
20 #define __jack_midi_unpack_h__
21 
22 enum {
23  MIDI_UNPACK_MAX_MSG = 1024
24 };
25 
26 typedef struct
27 {
28  int pos, need, size;
29  unsigned char data[MIDI_UNPACK_MAX_MSG];
30 }
32 
33 static inline
34 void midi_unpack_init(midi_unpack_t *u)
35 {
36  u->pos = 0;
37  u->size = sizeof(u->data);
38  u->need = u->size;
39 }
40 
41 static inline
42 void midi_unpack_reset(midi_unpack_t *u)
43 {
44  u->pos = 0;
45  u->need = u->size;
46 }
47 
48 static const unsigned char midi_voice_len[] =
49  {
50  3, /*0x80 Note Off*/
51  3, /*0x90 Note On*/
52  3, /*0xA0 Aftertouch*/
53  3, /*0xB0 Control Change*/
54  2, /*0xC0 Program Change*/
55  2, /*0xD0 Channel Pressure*/
56  3, /*0xE0 Pitch Wheel*/
57  1 /*0xF0 System*/
58  };
59 
60 static const unsigned char midi_system_len[] =
61  {
62  0, /*0xF0 System Exclusive Start*/
63  2, /*0xF1 MTC Quarter Frame*/
64  3, /*0xF2 Song Postion*/
65  2, /*0xF3 Song Select*/
66  0, /*0xF4 undefined*/
67  0, /*0xF5 undefined*/
68  1, /*0xF6 Tune Request*/
69  1 /*0xF7 System Exlusive End*/
70  };
71 
72 static
73 int midi_unpack_buf(midi_unpack_t *buf, const unsigned char *data, int len, void *jack_port_buf, jack_nframes_t time)
74 {
75  int i;
76  for (i = 0; i < len; ++i) {
77  const unsigned char byte = data[i];
78  if (byte >= 0xF8) // system realtime
79  {
80  jack_midi_event_write(jack_port_buf, time, &data[i], 1);
81  //printf("midi_unpack: written system relatime event\n");
82  //midi_input_write(in, &data[i], 1);
83  } else if (byte < 0x80) // data
84  {
85  assert (buf->pos < buf->size);
86  buf->data[buf->pos++] = byte;
87  } else if (byte < 0xF0) // voice
88  {
89  assert (byte >= 0x80 && byte < 0xF0);
90  //buf->need = ((byte|0x0F) == 0xCF || (byte|0x0F)==0xDF) ? 2 : 3;
91  buf->need = midi_voice_len[(byte-0x80)>>4];
92  buf->data[0] = byte;
93  buf->pos = 1;
94  } else if (byte == 0xF7) // sysex end
95  {
96  assert (buf->pos < buf->size);
97  buf->data[buf->pos++] = byte;
98  buf->need = buf->pos;
99  } else {
100  assert (byte >= 0xF0 && byte < 0xF8);
101  buf->pos = 1;
102  buf->data[0] = byte;
103  buf->need = midi_system_len[byte - 0xF0];
104  if (!buf->need)
105  buf->need = buf->size;
106  }
107  if (buf->pos == buf->need) {
108  // TODO: deal with big sysex'es (they are silently dropped for now)
109  if (buf->data[0] >= 0x80 || (buf->data[0] == 0xF0 && buf->data[buf->pos-1] == 0xF7)) {
110  /* convert Note On with velocity 0 to Note Off */
111  if ((buf->data[0] & 0xF0) == 0x90 && buf->data[2] == 0) {
112  // we use temp array here to keep running status sync
113  jack_midi_data_t temp[3] = { 0x80, 0, 0x40 };
114  temp[0] |= buf->data[0] & 0x0F;
115  temp[1] = buf->data[1];
116  jack_midi_event_write(jack_port_buf, time, temp, 3);
117  } else
118  jack_midi_event_write(jack_port_buf, time, &buf->data[0], buf->pos);
119  //printf("midi_unpack: written %d-byte event\n", buf->pos);
120  //midi_input_write(in, &buf->data[0], buf->pos);
121  }
122  /* keep running status */
123  if (buf->data[0] >= 0x80 && buf->data[0] < 0xF0)
124  buf->pos = 1;
125  else {
126  buf->pos = 0;
127  buf->need = buf->size;
128  }
129  }
130  }
131  assert (i == len);
132  return i;
133 }
134 
135 #endif /* __jack_midi_unpack_h__ */
LIB_EXPORT int jack_midi_event_write(void *port_buffer, jack_nframes_t time, const jack_midi_data_t *data, size_t data_size)