modules/audio_output/sndio.c

   1 /*****************************************************************************
   2  * sndio.c : sndio plugin for VLC
   3  *****************************************************************************
   4  * Copyright (C) 2012 Rémi Denis-Courmont
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU Lesser General Public License as published by
   8  * the Free Software Foundation; either version 2.1 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  14  * GNU Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public License
  17  * along with this program; if not, write to the Free Software Foundation,
  18  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  19  *****************************************************************************/
  20
  21 #ifdef HAVE_CONFIG_H
  22 # include "config.h"
  23 #endif
  24
  25 #include <math.h>
  26 #include <assert.h>
  27
  28 #include <vlc_common.h>
  29 #include <vlc_plugin.h>
  30 #include <vlc_aout.h>
  31
  32 #include <sndio.h>
  33
  34 static int Open (vlc_object_t *);
  35 static void Close (vlc_object_t *);
  36
  37 vlc_module_begin ()
  38     set_shortname ("sndio")
  39     set_description (N_("OpenBSD sndio audio output"))
  40     set_category (CAT_AUDIO)
  41     set_subcategory (SUBCAT_AUDIO_AOUT)
  42     set_capability ("audio output", 120)
  43     set_callbacks (Open, Close)
  44 vlc_module_end ()
  45
  46 static int TimeGet (audio_output_t *, mtime_t *);
  47 static void Play (audio_output_t *, block_t *);
  48 static void Flush (audio_output_t *, bool);
  49 static int VolumeSet (audio_output_t *, float);
  50 static int MuteSet (audio_output_t *, bool);
  51 static void VolumeChanged (void *, unsigned);
  52 static void PositionChanged (void *, int);
  53
  54 struct aout_sys_t
  55 {
  56     struct sio_hdl *hdl;
  57     int started;
  58     int delay;
  59     unsigned rate;
  60     unsigned volume;
  61     bool mute;
  62 };
  63
  64 /** Initializes an sndio playback stream */
  65 static int Start (audio_output_t *aout, audio_sample_format_t *restrict fmt)
  66 {
  67     aout_sys_t *sys = aout->sys;
  68
  69     if (aout_FormatNbChannels(fmt) == 0)
  70         return VLC_EGENERIC;
  71
  72     sys->hdl = sio_open (NULL, SIO_PLAY, 0 /* blocking */);
  73     if (sys->hdl == NULL)
  74     {
  75         msg_Err (aout, "cannot create audio playback stream");
  76         return VLC_EGENERIC;
  77     }
  78
  79     struct sio_par par;
  80     sio_initpar (&par);
  81     switch (fmt->i_format) {
  82     case VLC_CODEC_U8:
  83         par.bits = 8;
  84         par.sig = 0;
  85         break;
  86     case VLC_CODEC_S16N:
  87         par.bits = 16;
  88         par.sig = 1;
  89         par.le = SIO_LE_NATIVE;
  90         break;
  91     case VLC_CODEC_S32N:
  92     case VLC_CODEC_FL32:
  93     case VLC_CODEC_FL64:
  94         par.bits = 32;
  95         par.sig = 1;
  96         par.le = SIO_LE_NATIVE;
  97         break;
  98     default:
  99         /* use a common audio format */
 100         par.bits = 16;
 101         par.sig = 1;
 102         par.le = SIO_LE_NATIVE;
 103     }
 104     par.pchan = aout_FormatNbChannels (fmt);
 105     par.rate = fmt->i_rate;
 106     par.round = par.rate / 50;
 107     par.appbufsz = par.rate / 4;
 108
 109     if (!sio_setpar (sys->hdl, &par) || !sio_getpar (sys->hdl, &par))
 110     {
 111         msg_Err (aout, "cannot negotiate audio playback parameters");
 112         goto error;
 113     }
 114
 115     if (par.bps != par.bits >> 3 && !par.msb)
 116     {
 117         msg_Err (aout, "unsupported audio sample format (%u bits in %u bytes)",
 118                  par.bits, par.bps);
 119         goto error;
 120     }
 121     if (par.sig != (par.bits != 8))
 122     {
 123         msg_Err (aout, "unsupported audio sample format (%ssigned)",
 124                  par.sig ? "" : "un");
 125         goto error;
 126     }
 127     if (par.bps > 1 && par.le != SIO_LE_NATIVE)
 128     {
 129         msg_Err (aout, "unsupported audio sample format (%s endian)",
 130                  par.le ? "little" : "big");
 131         goto error;
 132     }
 133     switch (par.bits)
 134     {
 135         case 8:
 136             fmt->i_format = VLC_CODEC_U8;
 137             break;
 138         case 16:
 139             fmt->i_format = VLC_CODEC_S16N;
 140             break;
 141         case 32:
 142             fmt->i_format = VLC_CODEC_S32N;
 143             break;
 144         default:
 145             msg_Err (aout, "unsupported audio sample format (%u bits)",
 146                      par.bits);
 147             goto error;
 148     }
 149
 150     fmt->i_rate = par.rate;
 151     sys->rate = par.rate;
 152
 153     /* Channel map */
 154     unsigned chans;
 155     switch (par.pchan)
 156     {
 157         case 1:
 158             chans = AOUT_CHAN_CENTER;
 159             break;
 160         case 2:
 161             chans = AOUT_CHANS_STEREO;
 162             break;
 163         case 4:
 164             chans = AOUT_CHANS_4_0;
 165             break;
 166         case 6:
 167             chans = AOUT_CHANS_5_1;
 168             break;
 169         case 8:
 170             chans = AOUT_CHANS_7_1;
 171             break;
 172         default:
 173             msg_Err (aout, "unknown %u channels map", par.pchan);
 174             goto error;
 175     }
 176
 177     fmt->channel_type = AUDIO_CHANNEL_TYPE_BITMAP;
 178     fmt->i_physical_channels = chans;
 179     aout_FormatPrepare (fmt);
 180
 181     aout->time_get = TimeGet;
 182     aout->play = Play;
 183     aout->pause = NULL;
 184     aout->flush = Flush;
 185     if (sio_onvol(sys->hdl, VolumeChanged, aout))
 186     {
 187         aout->volume_set = VolumeSet;
 188         aout->mute_set = MuteSet;
 189     }
 190     else
 191     {
 192         aout->volume_set = NULL;
 193         aout->mute_set = NULL;
 194     }
 195
 196     sys->started = 0;
 197     sys->delay = 0;
 198     sio_onmove (sys->hdl, PositionChanged, aout);
 199     sio_start (sys->hdl);
 200     return VLC_SUCCESS;
 201
 202 error:
 203     sio_close (sys->hdl);
 204     return VLC_EGENERIC;
 205 }
 206
 207 static void Stop (audio_output_t *aout)
 208 {
 209     aout_sys_t *sys = aout->sys;
 210
 211     sio_close (sys->hdl);
 212 }
 213
 214 static void PositionChanged (void *arg, int delta)
 215 {
 216     audio_output_t *aout = arg;
 217     aout_sys_t *sys = aout->sys;
 218
 219     sys->delay -= delta;
 220     sys->started = 1;
 221 }
 222
 223 static int TimeGet (audio_output_t *aout, mtime_t *restrict delay)
 224 {
 225     aout_sys_t *sys = aout->sys;
 226
 227     if (!sys->started)
 228         return -1;
 229     *delay = (mtime_t)sys->delay * CLOCK_FREQ / sys->rate;
 230     return 0;
 231 }
 232
 233 static void Play (audio_output_t *aout, block_t *block)
 234 {
 235     aout_sys_t *sys = aout->sys;
 236
 237     sio_write (sys->hdl, block->p_buffer, block->i_buffer);
 238     sys->delay += block->i_nb_samples;
 239     block_Release (block);
 240 }
 241
 242 static void Flush (audio_output_t *aout, bool wait)
 243 {
 244     aout_sys_t *sys = aout->sys;
 245
 246     sio_stop (sys->hdl);
 247     sys->started = 0;
 248     sys->delay = 0;
 249     sio_start (sys->hdl);
 250     (void)wait;
 251 }
 252
 253 static void VolumeChanged (void *arg, unsigned volume)
 254 {
 255     audio_output_t *aout = arg;
 256     float fvol = (float)volume / (float)SIO_MAXVOL;
 257
 258     aout_VolumeReport (aout, fvol);
 259     aout_MuteReport (aout, volume == 0);
 260     if (volume) /* remember last non-zero volume to unmute later */
 261         aout->sys->volume = volume;
 262 }
 263
 264 static int VolumeSet (audio_output_t *aout, float fvol)
 265 {
 266     aout_sys_t *sys = aout->sys;
 267     unsigned volume;
 268
 269     if (fvol < 0)
 270         fvol = 0;
 271     if (fvol > 1)
 272         fvol = 1;
 273     volume = lroundf (fvol * SIO_MAXVOL);
 274     if (!sys->mute && !sio_setvol (sys->hdl, volume))
 275         return -1;
 276     sys->volume = volume;
 277     return 0;
 278 }
 279
 280 static int MuteSet (audio_output_t *aout, bool mute)
 281 {
 282     aout_sys_t *sys = aout->sys;
 283
 284     if (!sio_setvol (sys->hdl, mute ? 0 : sys->volume))
 285         return -1;
 286
 287     sys->mute = mute;
 288     return 0;
 289 }
 290
 291 static int Open (vlc_object_t *obj)
 292 {
 293     audio_output_t *aout = (audio_output_t *)obj;
 294     aout_sys_t *sys = malloc (sizeof (*sys));
 295     if (unlikely(sys == NULL))
 296         return VLC_ENOMEM;
 297
 298     aout->sys = sys;
 299     aout->start = Start;
 300     aout->stop = Stop;
 301     /* FIXME: set volume/mute here */
 302     return VLC_SUCCESS;
 303 }
 304
 305 static void Close (vlc_object_t *obj)
 306 {
 307     audio_output_t *aout = (audio_output_t *)obj;
 308     aout_sys_t *sys = aout->sys;
 309
 310     free (sys);
 311 }
 312