summaryrefslogtreecommitdiffstats
path: root/libao2/ao_jack.c
blob: ec7d1e538131055cd1d1eed3525dbc4edf186b84 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
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
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
/* 
 * ao_jack.c - libao2 JACK Audio Output Driver for MPlayer
 *
 * This driver is under the same license as MPlayer.
 * (http://www.mplayerhq.hu)
 *
 * Copyleft 2001 by Felix Bünemann (atmosfear@users.sf.net)
 * and Reimar Döffinger (Reimar.Doeffinger@stud.uni-karlsruhe.de)
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "config.h"
#include "mp_msg.h"
#include "help_mp.h"

#include "audio_out.h"
#include "audio_out_internal.h"
#include "libaf/af_format.h"
#include "osdep/timer.h"
#include "subopt-helper.h"

#include "libvo/fastmemcpy.h"

#include <jack/jack.h>

static ao_info_t info = 
{
  "JACK audio output",
  "jack",
  "Reimar Döffinger <Reimar.Doeffinger@stud.uni-karlsruhe.de>",
  "based on ao_sdl.c"
};

LIBAO_EXTERN(jack)

//! maximum number of channels supported, avoids lots of mallocs
#define MAX_CHANS 6
static jack_port_t *ports[MAX_CHANS];
static int num_ports; ///< Number of used ports == number of channels
static jack_client_t *client;
static float jack_latency;
static int estimate;
static volatile int paused = 0; ///< set if paused
static volatile int underrun = 0; ///< signals if an underrun occured

static volatile float callback_interval = 0;
static volatile float callback_time = 0;

//! size of one chunk, if this is too small MPlayer will start to "stutter"
//! after a short time of playback
#define CHUNK_SIZE (16 * 1024)
//! number of "virtual" chunks the buffer consists of
#define NUM_CHUNKS 8
// This type of ring buffer may never fill up completely, at least
// one byte must always be unused.
// For performance reasons (alignment etc.) one whole chunk always stays
// empty, not only one byte.
#define BUFFSIZE ((NUM_CHUNKS + 1) * CHUNK_SIZE)

//! buffer for audio data
static unsigned char *buffer = NULL;

//! buffer read position, may only be modified by playback thread or while it is stopped
static volatile int read_pos;
//! buffer write position, may only be modified by MPlayer's thread
static volatile int write_pos;

/**
 * \brief get the number of free bytes in the buffer
 * \return number of free bytes in buffer
 * 
 * may only be called by MPlayer's thread
 * return value may change between immediately following two calls,
 * and the real number of free bytes might be larger!
 */
static int buf_free() {
  int free = read_pos - write_pos - CHUNK_SIZE;
  if (free < 0) free += BUFFSIZE;
  return free;
}

/**
 * \brief get amount of data available in the buffer
 * \return number of bytes available in buffer
 *
 * may only be called by the playback thread
 * return value may change between immediately following two calls,
 * and the real number of buffered bytes might be larger!
 */
static int buf_used() {
  int used = write_pos - read_pos;
  if (used < 0) used += BUFFSIZE;
  return used;
}

/**
 * \brief insert len bytes into buffer
 * \param data data to insert
 * \param len length of data
 * \return number of bytes inserted into buffer
 *
 * If there is not enough room, the buffer is filled up
 */
static int write_buffer(unsigned char* data, int len) {
  int first_len = BUFFSIZE - write_pos;
  int free = buf_free();
  if (len > free) len = free;
  if (first_len > len) first_len = len;
  // till end of buffer
  memcpy (&buffer[write_pos], data, first_len);
  if (len > first_len) { // we have to wrap around
    // remaining part from beginning of buffer
    memcpy (buffer, &data[first_len], len - first_len);
  }
  write_pos = (write_pos + len) % BUFFSIZE;
  return len;
}

/**
 * \brief read data from buffer and splitting it into channels
 * \param bufs num_bufs float buffers, each will contain the data of one channel
 * \param cnt number of samples to read per channel
 * \param num_bufs number of channels to split the data into
 * \return number of samples read per channel, equals cnt unless there was too
 *         little data in the buffer
 *
 * Assumes the data in the buffer is of type float, the number of bytes
 * read is res * num_bufs * sizeof(float), where res is the return value.
 */
static int read_buffer(float **bufs, int cnt, int num_bufs) {
  int first_len = BUFFSIZE - read_pos;
  int buffered = buf_used();
  int i, j;
  if (cnt * sizeof(float) * num_bufs > buffered)
    cnt = buffered / sizeof(float) / num_bufs;
  for (i = 0; i < cnt; i++) {
    for (j = 0; j < num_bufs; j++) {
      bufs[j][i] = *((float *)(&buffer[read_pos]));
      read_pos = (read_pos + sizeof(float)) % BUFFSIZE;
    }
  }
  return cnt;
}

// end ring buffer stuff

static int control(int cmd, void *arg) {
  return CONTROL_UNKNOWN;
}

/**
 * \brief fill the buffers with silence
 * \param bufs num_bufs float buffers, each will contain the data of one channel
 * \param cnt number of samples in each buffer
 * \param num_bufs number of buffers
 */
static void silence(float **bufs, int cnt, int num_bufs) {
  int i, j;
  for (i = 0; i < cnt; i++)
    for (j = 0; j < num_bufs; j++)
      bufs[j][i] = 0;
}

/**
 * \brief JACK Callback function
 * \param nframes number of frames to fill into buffers
 * \param arg unused
 * \return currently always 0
 *
 * Write silence into buffers if paused or an underrun occured
 */
static int outputaudio(jack_nframes_t nframes, void *arg) {
  float *bufs[MAX_CHANS];
  int i;
  for (i = 0; i < num_ports; i++)
    bufs[i] = jack_port_get_buffer(ports[i], nframes);
  if (!paused && !underrun)
    if (read_buffer(bufs, nframes, num_ports) < nframes)
      underrun = 1;
  if (paused || underrun)
    silence(bufs, nframes, num_ports);
  if (estimate) {
    float now = (float)GetTimer() / 1000000.0;
    float diff = callback_time + callback_interval - now;
    if ((diff > -0.002) && (diff < 0.002))
      callback_time += callback_interval;
    else
      callback_time = now;
    callback_interval = (float)nframes / (float)ao_data.samplerate;
  }
  return 0;
}

/**
 * \brief print suboption usage help
 */
static void print_help ()
{
  mp_msg (MSGT_AO, MSGL_FATAL,
           "\n-ao jack commandline help:\n"
           "Example: mplayer -ao jack:port=myout\n"
           "  connects MPlayer to the jack ports named myout\n"
           "\nOptions:\n"
           "  port=<port name>\n"
           "    Connects to the given ports instead of the default physical ones\n"
           "  name=<client name>\n"
           "    Client name to pass to JACK\n"
           "  estimate\n"
           "    Estimates the amount of data in buffers (experimental)\n");
}

static int init(int rate, int channels, int format, int flags) {
  const char **matching_ports = NULL;
  char *port_name = NULL;
  char *client_name = NULL;
  opt_t subopts[] = {
    {"port", OPT_ARG_MSTRZ, &port_name, NULL},
    {"name", OPT_ARG_MSTRZ, &client_name, NULL},
    {"estimate", OPT_ARG_BOOL, &estimate, NULL},
    {NULL}
  };
  int port_flags = JackPortIsInput;
  int i;
  estimate = 1;
  if (subopt_parse(ao_subdevice, subopts) != 0) {
    print_help();
    return 0;
  }
  if (channels > MAX_CHANS) {
    mp_msg(MSGT_AO, MSGL_FATAL, "[JACK] Invalid number of channels: %i\n", channels);
    goto err_out;
  }
  if (!client_name) {
    client_name = (char *)malloc(40);
  sprintf(client_name, "MPlayer [%d]", getpid());
  }
  client = jack_client_new(client_name);
  if (!client) {
    mp_msg(MSGT_AO, MSGL_FATAL, "[JACK] cannot open server\n");
    goto err_out;
  }
  reset();
  jack_set_process_callback(client, outputaudio, 0);

  // list matching ports
  if (!port_name)
    port_flags |= JackPortIsPhysical;
  matching_ports = jack_get_ports(client, port_name, NULL, port_flags);
  for (num_ports = 0; matching_ports && matching_ports[num_ports]; num_ports++) ;
  if (!num_ports) {
    mp_msg(MSGT_AO, MSGL_FATAL, "[JACK] no physical ports available\n");
    goto err_out;
  }
  if (channels > num_ports) channels = num_ports;
  num_ports = channels;

  // create out output ports
  for (i = 0; i < num_ports; i++) {
    char pname[30];
    snprintf(pname, 30, "out_%d", i);
    ports[i] = jack_port_register(client, pname, JACK_DEFAULT_AUDIO_TYPE, JackPortIsOutput, 0);
    if (!ports[i]) {
      mp_msg(MSGT_AO, MSGL_FATAL, "[JACK] not enough ports available\n");
      goto err_out;
    }
  }
  if (jack_activate(client)) {
    mp_msg(MSGT_AO, MSGL_FATAL, "[JACK] activate failed\n");
    goto err_out;
  }
  for (i = 0; i < num_ports; i++) {
    if (jack_connect(client, jack_port_name(ports[i]), matching_ports[i])) {
      mp_msg(MSGT_AO, MSGL_FATAL, "[JACK] connecting failed\n");
      goto err_out;
    }
  }
  rate = jack_get_sample_rate(client);
  jack_latency = (float)(jack_port_get_total_latency(client, ports[0]) +
                         jack_get_buffer_size(client)) / (float)rate;
  callback_interval = 0;
  buffer = (unsigned char *) malloc(BUFFSIZE);

  ao_data.channels = channels;
  ao_data.samplerate = rate;
  ao_data.format = AF_FORMAT_FLOAT_NE;
  ao_data.bps = channels * rate * sizeof(float);
  ao_data.buffersize = CHUNK_SIZE * NUM_CHUNKS;
  ao_data.outburst = CHUNK_SIZE;
  free(matching_ports);
  free(port_name);
  free(client_name);
  return 1;

err_out:
  free(matching_ports);
  free(port_name);
  free(client_name);
  if (client)
    jack_client_close(client);
  free(buffer);
  buffer = NULL;
  return 0;
}

// close audio device
static void uninit(int immed) {
  if (!immed)
    usec_sleep(get_delay() * 1000 * 1000);
  // HACK, make sure jack doesn't loop-output dirty buffers
  reset();
  usec_sleep(100 * 1000);
  jack_client_close(client);
  free(buffer);
  buffer = NULL;
}

/**
 * \brief stop playing and empty buffers (for seeking/pause)
 */
static void reset() {
  paused = 1;
  read_pos = 0;
  write_pos = 0;
  paused = 0;
}

/**
 * \brief stop playing, keep buffers (for pause)
 */
static void audio_pause() {
  paused = 1;
}

/**
 * \brief resume playing, after audio_pause()
 */
static void audio_resume() {
  paused = 0;
}

static int get_space() {
  return buf_free();
}

/**
 * \brief write data into buffer and reset underrun flag
 */
static int play(void *data, int len, int flags) {
  len -= len % ao_data.outburst;
  underrun = 0;
  return write_buffer(data, len);
}

static float get_delay() {
  int buffered = BUFFSIZE - CHUNK_SIZE - buf_free(); // could be less
  float in_jack = jack_latency;
  if (estimate && callback_interval > 0) {
    float elapsed = (float)GetTimer() / 1000000.0 - callback_time;
    in_jack += callback_interval - elapsed;
    if (in_jack < 0) in_jack = 0;
  }
  return (float)buffered / (float)ao_data.bps + in_jack;
}