code.delx.au - pulseaudio/blob - polyp/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 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 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 #include <sys/poll.h>
  29
  30 #include <asoundlib.h>
  31
  32 #include "module.h"
  33 #include "core.h"
  34 #include "memchunk.h"
  35 #include "sink.h"
  36 #include "modargs.h"
  37 #include "util.h"
  38 #include "sample-util.h"
  39 #include "alsa-util.h"
  40 #include "xmalloc.h"
  41
  42 struct userdata {
  43     snd_pcm_t *pcm_handle;
  44     struct pa_sink *sink;
  45     struct pa_io_event **io_events;
  46     unsigned n_io_events;
  47
  48     size_t frame_size, fragment_size;
  49     struct pa_memchunk memchunk, silence;
  50     struct pa_module *module;
  51 };
  52
  53 static const char* const valid_modargs[] = {
  54     "device",
  55     "sink_name",
  56     "format",
  57     "channels",
  58     "rate",
  59     "fragments",
  60     "fragment_size",
  61     NULL
  62 };
  63
  64 #define DEFAULT_SINK_NAME "alsa_output"
  65 #define DEFAULT_DEVICE "plughw:0,0"
  66
  67 static void update_usage(struct userdata *u) {
  68    pa_module_set_used(u->module,
  69                       (u->sink ? pa_idxset_ncontents(u->sink->inputs) : 0) +
  70                       (u->sink ? pa_idxset_ncontents(u->sink->monitor_source->outputs) : 0));
  71 }
  72
  73 static void xrun_recovery(struct userdata *u) {
  74     assert(u);
  75
  76     fprintf(stderr, "*** ALSA-XRUN (playback) ***\n");
  77
  78     if (snd_pcm_prepare(u->pcm_handle) < 0)
  79         fprintf(stderr, "snd_pcm_prepare() failed\n");
  80 }
  81
  82 static void do_write(struct userdata *u) {
  83     assert(u);
  84
  85     update_usage(u);
  86
  87     for (;;) {
  88         struct pa_memchunk *memchunk = NULL;
  89         snd_pcm_sframes_t frames;
  90
  91         if (u->memchunk.memblock)
  92             memchunk = &u->memchunk;
  93         else {
  94             if (pa_sink_render(u->sink, u->fragment_size, &u->memchunk) < 0)
  95                 memchunk = &u->silence;
  96             else
  97                 memchunk = &u->memchunk;
  98         }
  99
 100         assert(memchunk->memblock && memchunk->memblock->data && memchunk->length && memchunk->memblock->length && (memchunk->length % u->frame_size) == 0);
 101
 102         if ((frames = snd_pcm_writei(u->pcm_handle, memchunk->memblock->data + memchunk->index, memchunk->length / u->frame_size)) < 0) {
 103             if (frames == -EAGAIN)
 104                 return;
 105
 106             if (frames == -EPIPE) {
 107                 xrun_recovery(u);
 108                 continue;
 109             }
 110
 111             fprintf(stderr, "snd_pcm_writei() failed\n");
 112             return;
 113         }
 114
 115         if (memchunk == &u->memchunk) {
 116             size_t l = frames * u->frame_size;
 117             memchunk->index += l;
 118             memchunk->length -= l;
 119
 120             if (memchunk->length == 0) {
 121                 pa_memblock_unref(memchunk->memblock);
 122                 memchunk->memblock = NULL;
 123                 memchunk->index = memchunk->length = 0;
 124             }
 125         }
 126
 127         break;
 128     }
 129 }
 130
 131 static void io_callback(struct pa_mainloop_api*a, struct pa_io_event *e, int fd, enum pa_io_event_flags f, void *userdata) {
 132     struct userdata *u = userdata;
 133     assert(u && a && e);
 134
 135     if (snd_pcm_state(u->pcm_handle) == SND_PCM_STATE_XRUN)
 136         xrun_recovery(u);
 137
 138     do_write(u);
 139 }
 140
 141 static uint32_t sink_get_latency_cb(struct pa_sink *s) {
 142     struct userdata *u = s->userdata;
 143     snd_pcm_sframes_t frames;
 144     assert(s && u && u->sink);
 145
 146     if (snd_pcm_delay(u->pcm_handle, &frames) < 0) {
 147         fprintf(stderr, __FILE__": failed to get delay\n");
 148         s->get_latency = NULL;
 149         return 0;
 150     }
 151
 152     if (frames < 0)
 153         frames = 0;
 154
 155     return pa_bytes_to_usec(frames * u->frame_size, &s->sample_spec);
 156 }
 157
 158 int pa_module_init(struct pa_core *c, struct pa_module*m) {
 159     struct pa_modargs *ma = NULL;
 160     int ret = -1;
 161     struct userdata *u = NULL;
 162     const char *dev;
 163     struct pa_sample_spec ss;
 164     unsigned periods, fragsize;
 165     snd_pcm_uframes_t buffer_size;
 166     size_t frame_size;
 167
 168     if (!(ma = pa_modargs_new(m->argument, valid_modargs))) {
 169         fprintf(stderr, __FILE__": failed to parse module arguments\n");
 170         goto fail;
 171     }
 172
 173     ss = c->default_sample_spec;
 174     if (pa_modargs_get_sample_spec(ma, &ss) < 0) {
 175         fprintf(stderr, __FILE__": failed to parse sample specification\n");
 176         goto fail;
 177     }
 178     frame_size = pa_frame_size(&ss);
 179
 180     periods = 12;
 181     fragsize = 1024;
 182     if (pa_modargs_get_value_u32(ma, "fragments", &periods) < 0 || pa_modargs_get_value_u32(ma, "fragment_size", &fragsize) < 0) {
 183         fprintf(stderr, __FILE__": failed to parse buffer metrics\n");
 184         goto fail;
 185     }
 186     buffer_size = fragsize/frame_size*periods;
 187
 188     u = pa_xmalloc0(sizeof(struct userdata));
 189     m->userdata = u;
 190     u->module = m;
 191
 192     if (snd_pcm_open(&u->pcm_handle, dev = pa_modargs_get_value(ma, "device", DEFAULT_DEVICE), SND_PCM_STREAM_PLAYBACK, SND_PCM_NONBLOCK) < 0) {
 193         fprintf(stderr, __FILE__": Error opening PCM device %s\n", dev);
 194         goto fail;
 195     }
 196
 197     if (pa_alsa_set_hw_params(u->pcm_handle, &ss, &periods, &buffer_size) < 0) {
 198         fprintf(stderr, __FILE__": Failed to set hardware parameters\n");
 199         goto fail;
 200     }
 201
 202     u->sink = pa_sink_new(c, pa_modargs_get_value(ma, "sink_name", DEFAULT_SINK_NAME), 0, &ss);
 203     assert(u->sink);
 204
 205     u->sink->get_latency = sink_get_latency_cb;
 206     u->sink->userdata = u;
 207     pa_sink_set_owner(u->sink, m);
 208     u->sink->description = pa_sprintf_malloc("Advanced Linux Sound Architecture PCM on '%s'", dev);
 209
 210     if (pa_create_io_events(u->pcm_handle, c->mainloop, &u->io_events, &u->n_io_events, io_callback, u) < 0) {
 211         fprintf(stderr, __FILE__": failed to obtain file descriptors\n");
 212         goto fail;
 213     }
 214
 215     u->frame_size = frame_size;
 216     u->fragment_size = buffer_size*u->frame_size/periods;
 217
 218     fprintf(stderr, __FILE__": using %u fragments of size %u bytes.\n", periods, u->fragment_size);
 219
 220     u->silence.memblock = pa_memblock_new(u->silence.length = u->fragment_size, c->memblock_stat);
 221     assert(u->silence.memblock);
 222     pa_silence_memblock(u->silence.memblock, &ss);
 223     u->silence.index = 0;
 224
 225     u->memchunk.memblock = NULL;
 226     u->memchunk.index = u->memchunk.length = 0;
 227
 228     ret = 0;
 229
 230 finish:
 231      if (ma)
 232          pa_modargs_free(ma);
 233
 234     return ret;
 235
 236 fail:
 237
 238     if (u)
 239         pa_module_done(c, m);
 240
 241     goto finish;
 242 }
 243
 244 void pa_module_done(struct pa_core *c, struct pa_module*m) {
 245     struct userdata *u;
 246     assert(c && m);
 247
 248     if (!(u = m->userdata))
 249         return;
 250
 251     if (u->sink)
 252         pa_sink_free(u->sink);
 253
 254     if (u->io_events)
 255         pa_free_io_events(c->mainloop, u->io_events, u->n_io_events);
 256
 257     if (u->pcm_handle) {
 258         snd_pcm_drop(u->pcm_handle);
 259         snd_pcm_close(u->pcm_handle);
 260     }
 261
 262     if (u->memchunk.memblock)
 263         pa_memblock_unref(u->memchunk.memblock);
 264     if (u->silence.memblock)
 265         pa_memblock_unref(u->silence.memblock);
 266
 267     pa_xfree(u);
 268 }
 269