code.delx.au - pulseaudio/blob - polyp/module-alsa-source.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
  41 struct userdata {
  42     snd_pcm_t *pcm_handle;
  43     struct pa_source *source;
  44     void **io_sources;
  45     unsigned n_io_sources;
  46
  47     size_t frame_size, fragment_size;
  48     struct pa_memchunk memchunk;
  49 };
  50
  51 static const char* const valid_modargs[] = {
  52     "device",
  53     "source_name",
  54     "format",
  55     "channels",
  56     "rate",
  57     "fragments",
  58     "fragment_size",
  59     NULL
  60 };
  61
  62 #define DEFAULT_SOURCE_NAME "alsa_input"
  63 #define DEFAULT_DEVICE "hw:0,0"
  64
  65 static void xrun_recovery(struct userdata *u) {
  66     assert(u);
  67
  68     fprintf(stderr, "*** ALSA-XRUN (capture) ***\n");
  69
  70     if (snd_pcm_prepare(u->pcm_handle) < 0)
  71         fprintf(stderr, "snd_pcm_prepare() failed\n");
  72 }
  73
  74 static void do_read(struct userdata *u) {
  75     assert(u);
  76
  77     for (;;) {
  78         struct pa_memchunk post_memchunk;
  79         snd_pcm_sframes_t frames;
  80         size_t l;
  81
  82         if (!u->memchunk.memblock) {
  83             u->memchunk.memblock = pa_memblock_new(u->memchunk.length = u->fragment_size);
  84             u->memchunk.index = 0;
  85         }
  86
  87         assert(u->memchunk.memblock && u->memchunk.memblock->data && u->memchunk.length && u->memchunk.memblock->length && (u->memchunk.length % u->frame_size) == 0);
  88
  89         if ((frames = snd_pcm_readi(u->pcm_handle, u->memchunk.memblock->data + u->memchunk.index, u->memchunk.length / u->frame_size)) < 0) {
  90             if (frames == -EAGAIN)
  91                 return;
  92
  93             if (frames == -EPIPE) {
  94                 xrun_recovery(u);
  95                 continue;
  96             }
  97
  98             fprintf(stderr, "snd_pcm_readi() failed: %s\n", strerror(-frames));
  99             return;
 100         }
 101
 102         l = frames * u->frame_size;
 103
 104         post_memchunk = u->memchunk;
 105         post_memchunk.length = l;
 106
 107         pa_source_post(u->source, &post_memchunk);
 108
 109         u->memchunk.index += l;
 110         u->memchunk.length -= l;
 111
 112         if (u->memchunk.length == 0) {
 113             pa_memblock_unref(u->memchunk.memblock);
 114             u->memchunk.memblock = NULL;
 115             u->memchunk.index = u->memchunk.length = 0;
 116         }
 117
 118         break;
 119     }
 120 }
 121
 122 static void io_callback(struct pa_mainloop_api*a, void *id, int fd, enum pa_mainloop_api_io_events events, void *userdata) {
 123     struct userdata *u = userdata;
 124     assert(u && a && id);
 125
 126     if (snd_pcm_state(u->pcm_handle) == SND_PCM_STATE_XRUN)
 127         xrun_recovery(u);
 128
 129     do_read(u);
 130 }
 131
 132 int pa_module_init(struct pa_core *c, struct pa_module*m) {
 133     struct pa_modargs *ma = NULL;
 134     int ret = -1;
 135     struct userdata *u = NULL;
 136     const char *dev;
 137     struct pa_sample_spec ss;
 138     unsigned periods, fragsize;
 139     snd_pcm_uframes_t buffer_size;
 140     size_t frame_size;
 141
 142     if (!(ma = pa_modargs_new(m->argument, valid_modargs))) {
 143         fprintf(stderr, __FILE__": failed to parse module arguments\n");
 144         goto fail;
 145     }
 146
 147     ss = c->default_sample_spec;
 148     if (pa_modargs_get_sample_spec(ma, &ss) < 0) {
 149         fprintf(stderr, __FILE__": failed to parse sample specification\n");
 150         goto fail;
 151     }
 152     frame_size = pa_frame_size(&ss);
 153
 154     periods = 12;
 155     fragsize = 1024;
 156     if (pa_modargs_get_value_u32(ma, "fragments", &periods) < 0 || pa_modargs_get_value_u32(ma, "fragment_size", &fragsize) < 0) {
 157         fprintf(stderr, __FILE__": failed to parse buffer metrics\n");
 158         goto fail;
 159     }
 160     buffer_size = fragsize/frame_size*periods;
 161
 162     u = malloc(sizeof(struct userdata));
 163     assert(u);
 164     memset(u, 0, sizeof(struct userdata));
 165     m->userdata = u;
 166
 167     if (snd_pcm_open(&u->pcm_handle, dev = pa_modargs_get_value(ma, "device", DEFAULT_DEVICE), SND_PCM_STREAM_CAPTURE, SND_PCM_NONBLOCK) < 0) {
 168         fprintf(stderr, __FILE__": Error opening PCM device %s\n", dev);
 169         goto fail;
 170     }
 171
 172     if (pa_alsa_set_hw_params(u->pcm_handle, &ss, &periods, &buffer_size) < 0) {
 173         fprintf(stderr, __FILE__": Failed to set hardware parameters\n");
 174         goto fail;
 175     }
 176
 177     u->source = pa_source_new(c, pa_modargs_get_value(ma, "source_name", DEFAULT_SOURCE_NAME), 0, &ss);
 178     assert(u->source);
 179
 180     u->source->userdata = u;
 181     pa_source_set_owner(u->source, m);
 182     u->source->description = pa_sprintf_malloc("Advanced Linux Sound Architecture PCM on '%s'", dev);
 183
 184     if (pa_create_io_sources(u->pcm_handle, c->mainloop, &u->io_sources, &u->n_io_sources, io_callback, u) < 0) {
 185         fprintf(stderr, __FILE__": failed to obtain file descriptors\n");
 186         goto fail;
 187     }
 188
 189     u->frame_size = frame_size;
 190     u->fragment_size = buffer_size*u->frame_size/periods;
 191
 192     fprintf(stderr, __FILE__": using %u fragments of size %u bytes.\n", periods, u->fragment_size);
 193
 194     u->memchunk.memblock = NULL;
 195     u->memchunk.index = u->memchunk.length = 0;
 196
 197     snd_pcm_start(u->pcm_handle);
 198
 199     ret = 0;
 200
 201 finish:
 202      if (ma)
 203          pa_modargs_free(ma);
 204
 205     return ret;
 206
 207 fail:
 208
 209     if (u)
 210         pa_module_done(c, m);
 211
 212     goto finish;
 213 }
 214
 215 void pa_module_done(struct pa_core *c, struct pa_module*m) {
 216     struct userdata *u;
 217     assert(c && m);
 218
 219     if ((u = m->userdata)) {
 220         if (u->source)
 221             pa_source_free(u->source);
 222
 223         if (u->io_sources)
 224             pa_free_io_sources(c->mainloop, u->io_sources, u->n_io_sources);
 225
 226         if (u->pcm_handle) {
 227             snd_pcm_drop(u->pcm_handle);
 228             snd_pcm_close(u->pcm_handle);
 229         }
 230
 231         if (u->memchunk.memblock)
 232             pa_memblock_unref(u->memchunk.memblock);
 233
 234         free(u);
 235     }
 236 }
 237