s_midi_alsa.c 7.57 KB
Newer Older
Miller Puckette's avatar
Miller Puckette committed
1
2
3
4
5
6
7
8
/* Copyright (c) 1997-1999 Guenter Geiger, Miller Puckette, Larry Troxler,
* Winfried Ritsch, Karl MacMillan, and others.
* For information on usage and redistribution, and for a DISCLAIMER OF ALL
* WARRANTIES, see the file, "LICENSE.txt," in this distribution.  */

/* MIDI I/O for Linux using ALSA */

#include <stdio.h>
Hans-Christoph Steiner's avatar
Hans-Christoph Steiner committed
9
#ifdef HAVE_UNISTD_H
Miller Puckette's avatar
Miller Puckette committed
10
11
12
13
14
15
16
17
18
19
20
#include <unistd.h>
#endif
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <errno.h>
#include <alsa/asoundlib.h>
#include "m_pd.h"
#include "s_stuff.h"

21
22
23
24
25
//the maximum length of input messages
#ifndef ALSA_MAX_EVENT_SIZE
#define ALSA_MAX_EVENT_SIZE 512
#endif

Miller Puckette's avatar
Miller Puckette committed
26
27
28
29
30
31
32
33
34
static int alsa_nmidiin;
static int alsa_midiinfd[MAXMIDIINDEV];
static int alsa_nmidiout;
static int alsa_midioutfd[MAXMIDIOUTDEV];

static snd_seq_t *midi_handle;

static snd_midi_event_t *midiev;

35
void midi_alsa_setndevs(int in, int out);
Miller Puckette's avatar
Miller Puckette committed
36
37
38
39
40
41
42
43
44
45

void sys_alsa_do_open_midi(int nmidiin, int *midiinvec,
    int nmidiout, int *midioutvec)
{

    char portname[50];
    int err = 0;
    int client;
    int i;
    snd_seq_client_info_t *alsainfo;
46

Miller Puckette's avatar
Miller Puckette committed
47
48
    alsa_nmidiin = 0;
    alsa_nmidiout = 0;
49
    midi_alsa_setndevs(alsa_nmidiin, alsa_nmidiout);
Miller Puckette's avatar
Miller Puckette committed
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106

    if (nmidiout == 0 && nmidiin == 0) return;

    if(nmidiin>MAXMIDIINDEV )
      {
        post("midi input ports reduced to maximum %d", MAXMIDIINDEV);
        nmidiin=MAXMIDIINDEV;
      }
    if(nmidiout>MAXMIDIOUTDEV)
      {
        post("midi output ports reduced to maximum %d", MAXMIDIOUTDEV);
        nmidiout=MAXMIDIOUTDEV;
      }

    if (nmidiin>0 && nmidiout>0)
        err = snd_seq_open(&midi_handle,"default",SND_SEQ_OPEN_DUPLEX,0);
    else if (nmidiin > 0)
        err = snd_seq_open(&midi_handle,"default",SND_SEQ_OPEN_INPUT,0);
    else if (nmidiout > 0)
        err = snd_seq_open(&midi_handle,"default",SND_SEQ_OPEN_OUTPUT,0);
    
    if (err!=0)
    {
            sys_setalarm(1000000);
            post("couldn't open alsa sequencer");
            return;
    }
    for (i=0;i<nmidiin;i++)
    {
        int port;
        sprintf(portname,"Pure Data Midi-In %d",i+1);
        port = snd_seq_create_simple_port(midi_handle,portname,
                                          SND_SEQ_PORT_CAP_WRITE |SND_SEQ_PORT_CAP_SUBS_WRITE, 
                                          SND_SEQ_PORT_TYPE_APPLICATION);
        alsa_midiinfd[i] = port;        
        if (port < 0) goto error;        
    }

    for (i=0;i<nmidiout;i++)
    {
        int port;
        sprintf(portname,"Pure Data Midi-Out %d",i+1);
        port = snd_seq_create_simple_port(midi_handle,portname,
                                          SND_SEQ_PORT_CAP_READ | SND_SEQ_PORT_CAP_SUBS_READ, 
                                          SND_SEQ_PORT_TYPE_APPLICATION);
        alsa_midioutfd[i] = port;       
        if (port < 0) goto error;        
    }
   
    snd_seq_client_info_malloc(&alsainfo);
    snd_seq_get_client_info(midi_handle,alsainfo);
    snd_seq_client_info_set_name(alsainfo,"Pure Data");
    client = snd_seq_client_info_get_client(alsainfo);
    snd_seq_set_client_info(midi_handle,alsainfo);
    snd_seq_client_info_free(alsainfo);
    post("Opened Alsa Client %d in:%d out:%d",client,nmidiin,nmidiout);
    sys_setalarm(0);
107
    snd_midi_event_new(ALSA_MAX_EVENT_SIZE,&midiev);
Miller Puckette's avatar
Miller Puckette committed
108
109
    alsa_nmidiout = nmidiout;
    alsa_nmidiin = nmidiin;
110
111
112
113
    // We need to keep the ALSA devices list (midi_alsa_getdevs) in sync with
    // the actual device config. Not sure why this table (used by the GUI)
    // uses its own device counts. -ag
    midi_alsa_setndevs(alsa_nmidiin, alsa_nmidiout);
Miller Puckette's avatar
Miller Puckette committed
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134

    return;
 error:
    sys_setalarm(1000000);
    post("couldn't open alsa MIDI output device");
    return;
}

#define md_msglen(x) (((x)<0xC0)?2:((x)<0xE0)?1:((x)<0xF0)?2:\
    ((x)==0xF2)?2:((x)<0xF4)?1:0)

void sys_alsa_putmidimess(int portno, int a, int b, int c)
{
    int channel;
    snd_seq_event_t ev;
    snd_seq_ev_clear(&ev);
    if (portno >= 0 && portno < alsa_nmidiout)
    {
        if (a >= 224)   // pitchbend
        {
            channel = a-224;
135
            snd_seq_ev_set_pitchbend(&ev, channel, (((c<<7)|b)-8192)); /* b and c are already correct but alsa needs to recalculate them */
Miller Puckette's avatar
Miller Puckette committed
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
        }
        else if (a >= 208)      // touch
        {
            channel = a-208;
            snd_seq_ev_set_chanpress(&ev,channel,b);
        }
        else if (a >= 192)      // program
        {
            channel = a-192;
            snd_seq_ev_set_pgmchange(&ev,channel,b);
        }
        else if (a >= 176)      // controller
        {
            channel = a-176;
            snd_seq_ev_set_controller(&ev,channel,b,c);
        }
        else if (a >= 160)      // polytouch
        {
            channel = a-160;
            snd_seq_ev_set_keypress(&ev,channel,b,c);
        }
        else if (a >= 144)      // note
        {
            channel = a-144;
160
            snd_seq_ev_set_noteon(&ev,channel,b,c);
Miller Puckette's avatar
Miller Puckette committed
161
162
163
164
165
166
167
168
169
170
171
        }
        snd_seq_ev_set_direct(&ev);
        snd_seq_ev_set_subs(&ev);
        snd_seq_ev_set_source(&ev,alsa_midioutfd[portno]);
        snd_seq_event_output_direct(midi_handle,&ev);
    }
    //post("%d %d %d\n",a,b,c);
}

void sys_alsa_putmidibyte(int portno, int byte)
{
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
  static snd_midi_event_t *dev = NULL;
  int res;
  snd_seq_event_t ev;
  if (!dev) {
    snd_midi_event_new(ALSA_MAX_EVENT_SIZE, &dev);
    //assert(dev);
    snd_midi_event_init(dev);
  }
  snd_seq_ev_clear(&ev);
  res = snd_midi_event_encode_byte(dev, byte, &ev);
  if (res > 0 && ev.type != SND_SEQ_EVENT_NONE) {
    // got a complete event, output it
    snd_seq_ev_set_direct(&ev);
    snd_seq_ev_set_subs(&ev);
    snd_seq_ev_set_source(&ev, alsa_midioutfd[portno]);
    snd_seq_event_output_direct(midi_handle, &ev);
  }
  if (res != 0)
    // reinitialize the parser
    snd_midi_event_init(dev);
Miller Puckette's avatar
Miller Puckette committed
192
193
194
195
196
197
}


    /* this version uses the asynchronous "read()" ... */
void sys_alsa_poll_midi(void)
{
198
   unsigned char buf[ALSA_MAX_EVENT_SIZE];
Miller Puckette's avatar
Miller Puckette committed
199
200
201
202
203
204
205
206
207
208
209
210
211
212
   int count, alsa_source;
   int i;
   snd_seq_event_t *midievent = NULL;

   if (alsa_nmidiout == 0 && alsa_nmidiin == 0) return;
   
   snd_midi_event_init(midiev);

   if (!alsa_nmidiout && !alsa_nmidiin) return;
   count = snd_seq_event_input_pending(midi_handle,1);
   if (count != 0)
        count = snd_seq_event_input(midi_handle,&midievent);
   if (midievent != NULL)
   {
213
       count = snd_midi_event_decode(midiev,buf,sizeof(buf),midievent);
Miller Puckette's avatar
Miller Puckette committed
214
215
216
217
218
219
220
221
222
223
       alsa_source = midievent->dest.port;
       for(i=0;i<count;i++)
           sys_midibytein(alsa_source, (buf[i] & 0xff));
       //post("received %d midi bytes\n",count);
   }
}

void sys_alsa_close_midi()
{
    alsa_nmidiin = alsa_nmidiout = 0;
224
    midi_alsa_setndevs(alsa_nmidiin, alsa_nmidiout);
Miller Puckette's avatar
Miller Puckette committed
225
226
227
    if(midi_handle)
      {
        snd_seq_close(midi_handle);
228
        midi_handle = NULL;
Miller Puckette's avatar
Miller Puckette committed
229
230
231
        if(midiev)
          {
            snd_midi_event_free(midiev);
232
            midiev = NULL;
Miller Puckette's avatar
Miller Puckette committed
233
234
235
236
237
238
239
240
241
242
243
244
245
246
          }
      }
}

#define NSEARCH 10
static int alsa_nmidiindevs, alsa_nmidioutdevs, alsa_initted;

void midi_alsa_init(void)     
{
    if (alsa_initted)
        return;
    alsa_initted = 1;
}

247
248
249
250
251
252
void midi_alsa_setndevs(int in, int out)
{
    alsa_nmidiindevs = in;
    alsa_nmidioutdevs = out;
}

Miller Puckette's avatar
Miller Puckette committed
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
void midi_alsa_getdevs(char *indevlist, int *nindevs,
    char *outdevlist, int *noutdevs, int maxndev, int devdescsize)
{
    int i, ndev;
    if ((ndev = alsa_nmidiindevs) > maxndev)
        ndev = maxndev;
    for (i = 0; i < ndev; i++)
        sprintf(indevlist + i * devdescsize, "ALSA MIDI device #%d", i+1);
    *nindevs = ndev;

    if ((ndev = alsa_nmidioutdevs) > maxndev)
        ndev = maxndev;
    for (i = 0; i < ndev; i++)
        sprintf(outdevlist + i * devdescsize, "ALSA MIDI device #%d", i+1);
    *noutdevs = ndev;
}