code.delx.au - pulseaudio/blob - src/modules/module-alsa-sink.c

   1 /* $Id$ */
   2
   3 /***
   4   This file is part of polypaudio.
   5
   6   polypaudio is free software; you can redistribute it and/or modify
   7   it under the terms of the GNU Lesser General Public License as published
   8   by the Free Software Foundation; either version 2 of the License,
   9   or (at your option) any later version.
  10
  11   polypaudio is distributed in the hope that it will be useful, but
  12   WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14   General Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public License
  17   along with polypaudio; if not, write to the Free Software
  18   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  19   USA.
  20 ***/
  21
  22 #ifdef HAVE_CONFIG_H
  23 #include <config.h>
  24 #endif
  25
  26 #include <assert.h>
  27 #include <stdio.h>
  28
  29 #ifdef HAVE_SYS_POLL_H
  30 #include <sys/poll.h>
  31 #else
  32 #include "poll.h"
  33 #endif
  34
  35 #include <asoundlib.h>
  36
  37 #include <polypcore/core.h>
  38 #include <polypcore/module.h>
  39 #include <polypcore/memchunk.h>
  40 #include <polypcore/sink.h>
  41 #include <polypcore/modargs.h>
  42 #include <polypcore/util.h>
  43 #include <polypcore/sample-util.h>
  44 #include <polypcore/alsa-util.h>
  45 #include <polypcore/xmalloc.h>
  46 #include <polypcore/log.h>
  47
  48 #include "module-alsa-sink-symdef.h"
  49
  50 PA_MODULE_AUTHOR("Lennart Poettering")
  51 PA_MODULE_DESCRIPTION("ALSA Sink")
  52 PA_MODULE_VERSION(PACKAGE_VERSION)
  53 PA_MODULE_USAGE("sink_name=<name for the sink> device=<ALSA device> format=<sample format> channels=<number of channels> rate=<sample rate> fragments=<number of fragments> fragment_size=<fragment size>")
  54
  55 struct userdata {
  56     snd_pcm_t *pcm_handle;
  57     pa_sink *sink;
  58     pa_io_event **io_events;
  59     unsigned n_io_events;
  60
  61     size_t frame_size, fragment_size;
  62     pa_memchunk memchunk, silence;
  63     pa_module *module;
  64 };
  65
  66 static const char* const valid_modargs[] = {
  67     "device",
  68     "sink_name",
  69     "format",
  70     "channels",
  71     "rate",
  72     "fragments",
  73     "fragment_size",
  74     NULL
  75 };
  76
  77 #define DEFAULT_SINK_NAME "alsa_output"
  78 #define DEFAULT_DEVICE "default"
  79
  80 static void update_usage(struct userdata *u) {
  81    pa_module_set_used(u->module,
  82                       (u->sink ? pa_idxset_size(u->sink->inputs) : 0) +
  83                       (u->sink ? pa_idxset_size(u->sink->monitor_source->outputs) : 0));
  84 }
  85
  86 static void xrun_recovery(struct userdata *u) {
  87     assert(u);
  88
  89     pa_log(__FILE__": *** ALSA-XRUN (playback) ***\n");
  90
  91     if (snd_pcm_prepare(u->pcm_handle) < 0)
  92         pa_log(__FILE__": snd_pcm_prepare() failed\n");
  93 }
  94
  95 static void do_write(struct userdata *u) {
  96     assert(u);
  97
  98     update_usage(u);
  99
 100     for (;;) {
 101         pa_memchunk *memchunk = NULL;
 102         snd_pcm_sframes_t frames;
 103
 104         if (u->memchunk.memblock)
 105             memchunk = &u->memchunk;
 106         else {
 107             if (pa_sink_render(u->sink, u->fragment_size, &u->memchunk) < 0)
 108                 memchunk = &u->silence;
 109             else
 110                 memchunk = &u->memchunk;
 111         }
 112
 113         assert(memchunk->memblock && memchunk->memblock->data && memchunk->length && memchunk->memblock->length && (memchunk->length % u->frame_size) == 0);
 114
 115         if ((frames = snd_pcm_writei(u->pcm_handle, (uint8_t*) memchunk->memblock->data + memchunk->index, memchunk->length / u->frame_size)) < 0) {
 116             if (frames == -EAGAIN)
 117                 return;
 118
 119             if (frames == -EPIPE) {
 120                 xrun_recovery(u);
 121                 continue;
 122             }
 123
 124             pa_log(__FILE__": snd_pcm_writei() failed\n");
 125             return;
 126         }
 127
 128         if (memchunk == &u->memchunk) {
 129             size_t l = frames * u->frame_size;
 130             memchunk->index += l;
 131             memchunk->length -= l;
 132
 133             if (memchunk->length == 0) {
 134                 pa_memblock_unref(memchunk->memblock);
 135                 memchunk->memblock = NULL;
 136                 memchunk->index = memchunk->length = 0;
 137             }
 138         }
 139
 140         break;
 141     }
 142 }
 143
 144 static void io_callback(pa_mainloop_api*a, pa_io_event *e, PA_GCC_UNUSED int fd, PA_GCC_UNUSED pa_io_event_flags_t f, void *userdata) {
 145     struct userdata *u = userdata;
 146     assert(u && a && e);
 147
 148     if (snd_pcm_state(u->pcm_handle) == SND_PCM_STATE_XRUN)
 149         xrun_recovery(u);
 150
 151     do_write(u);
 152 }
 153
 154 static pa_usec_t sink_get_latency_cb(pa_sink *s) {
 155     pa_usec_t r = 0;
 156     struct userdata *u = s->userdata;
 157     snd_pcm_sframes_t frames;
 158     assert(s && u && u->sink);
 159
 160     if (snd_pcm_delay(u->pcm_handle, &frames) < 0) {
 161         pa_log(__FILE__": failed to get delay\n");
 162         s->get_latency = NULL;
 163         return 0;
 164     }
 165
 166     if (frames < 0)
 167         frames = 0;
 168
 169     r += pa_bytes_to_usec(frames * u->frame_size, &s->sample_spec);
 170
 171     if (u->memchunk.memblock)
 172         r += pa_bytes_to_usec(u->memchunk.length, &s->sample_spec);
 173
 174     return r;
 175 }
 176
 177 int pa__init(pa_core *c, pa_module*m) {
 178     pa_modargs *ma = NULL;
 179     int ret = -1;
 180     struct userdata *u = NULL;
 181     const char *dev;
 182     pa_sample_spec ss;
 183     uint32_t periods, fragsize;
 184     snd_pcm_uframes_t period_size;
 185     size_t frame_size;
 186     int err;
 187
 188     if (!(ma = pa_modargs_new(m->argument, valid_modargs))) {
 189         pa_log(__FILE__": failed to parse module arguments\n");
 190         goto fail;
 191     }
 192
 193     ss = c->default_sample_spec;
 194     if (pa_modargs_get_sample_spec(ma, &ss) < 0) {
 195         pa_log(__FILE__": failed to parse sample specification\n");
 196         goto fail;
 197     }
 198     frame_size = pa_frame_size(&ss);
 199
 200     periods = 8;
 201     fragsize = 1024;
 202     if (pa_modargs_get_value_u32(ma, "fragments", &periods) < 0 || pa_modargs_get_value_u32(ma, "fragment_size", &fragsize) < 0) {
 203         pa_log(__FILE__": failed to parse buffer metrics\n");
 204         goto fail;
 205     }
 206     period_size = fragsize;
 207
 208     u = pa_xmalloc0(sizeof(struct userdata));
 209     m->userdata = u;
 210     u->module = m;
 211
 212     snd_config_update_free_global();
 213     if ((err = snd_pcm_open(&u->pcm_handle, dev = pa_modargs_get_value(ma, "device", DEFAULT_DEVICE), SND_PCM_STREAM_PLAYBACK, SND_PCM_NONBLOCK)) < 0) {
 214         pa_log(__FILE__": Error opening PCM device %s: %s\n", dev, snd_strerror(err));
 215         goto fail;
 216     }
 217
 218     if ((err = pa_alsa_set_hw_params(u->pcm_handle, &ss, &periods, &period_size)) < 0) {
 219         pa_log(__FILE__": Failed to set hardware parameters: %s\n", snd_strerror(err));
 220         goto fail;
 221     }
 222
 223     u->sink = pa_sink_new(c, __FILE__, pa_modargs_get_value(ma, "sink_name", DEFAULT_SINK_NAME), 0, &ss, NULL);
 224     assert(u->sink);
 225
 226     u->sink->get_latency = sink_get_latency_cb;
 227     u->sink->userdata = u;
 228     pa_sink_set_owner(u->sink, m);
 229     u->sink->description = pa_sprintf_malloc("Advanced Linux Sound Architecture PCM on '%s'", dev);
 230
 231     if (pa_create_io_events(u->pcm_handle, c->mainloop, &u->io_events, &u->n_io_events, io_callback, u) < 0) {
 232         pa_log(__FILE__": failed to obtain file descriptors\n");
 233         goto fail;
 234     }
 235
 236     u->frame_size = frame_size;
 237     u->fragment_size = period_size;
 238
 239     pa_log_info(__FILE__": using %u fragments of size %u bytes.\n", periods, u->fragment_size);
 240
 241     u->silence.memblock = pa_memblock_new(u->silence.length = u->fragment_size, c->memblock_stat);
 242     assert(u->silence.memblock);
 243     pa_silence_memblock(u->silence.memblock, &ss);
 244     u->silence.index = 0;
 245
 246     u->memchunk.memblock = NULL;
 247     u->memchunk.index = u->memchunk.length = 0;
 248
 249     ret = 0;
 250
 251 finish:
 252      if (ma)
 253          pa_modargs_free(ma);
 254
 255     return ret;
 256
 257 fail:
 258
 259     if (u)
 260         pa__done(c, m);
 261
 262     goto finish;
 263 }
 264
 265 void pa__done(pa_core *c, pa_module*m) {
 266     struct userdata *u;
 267     assert(c && m);
 268
 269     if (!(u = m->userdata))
 270         return;
 271
 272     if (u->sink) {
 273         pa_sink_disconnect(u->sink);
 274         pa_sink_unref(u->sink);
 275     }
 276
 277     if (u->io_events)
 278         pa_free_io_events(c->mainloop, u->io_events, u->n_io_events);
 279
 280     if (u->pcm_handle) {
 281         snd_pcm_drop(u->pcm_handle);
 282         snd_pcm_close(u->pcm_handle);
 283     }
 284
 285     if (u->memchunk.memblock)
 286         pa_memblock_unref(u->memchunk.memblock);
 287     if (u->silence.memblock)
 288         pa_memblock_unref(u->silence.memblock);
 289
 290     pa_xfree(u);
 291 }
 292