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 #include "xmalloc.h"
  41
  42 struct userdata {
  43     snd_pcm_t *pcm_handle;
  44     struct pa_source *source;
  45     void **io_sources;
  46     unsigned n_io_sources;
  47
  48     size_t frame_size, fragment_size;
  49     struct pa_memchunk memchunk;
  50     struct pa_module *module;
  51 };
  52
  53 static const char* const valid_modargs[] = {
  54     "device",
  55     "source_name",
  56     "format",
  57     "channels",
  58     "rate",
  59     "fragments",
  60     "fragment_size",
  61     NULL
  62 };
  63
  64 #define DEFAULT_SOURCE_NAME "alsa_input"
  65 #define DEFAULT_DEVICE "hw:0,0"
  66
  67 static void update_usage(struct userdata *u) {
  68    pa_module_set_used(u->module,
  69                       (u->source ? pa_idxset_ncontents(u->source->outputs) : 0));
  70 }
  71
  72 static void xrun_recovery(struct userdata *u) {
  73     assert(u);
  74
  75     fprintf(stderr, "*** ALSA-XRUN (capture) ***\n");
  76
  77     if (snd_pcm_prepare(u->pcm_handle) < 0)
  78         fprintf(stderr, "snd_pcm_prepare() failed\n");
  79 }
  80
  81 static void do_read(struct userdata *u) {
  82     assert(u);
  83
  84     update_usage(u);
  85
  86     for (;;) {
  87         struct pa_memchunk post_memchunk;
  88         snd_pcm_sframes_t frames;
  89         size_t l;
  90
  91         if (!u->memchunk.memblock) {
  92             u->memchunk.memblock = pa_memblock_new(u->memchunk.length = u->fragment_size);
  93             u->memchunk.index = 0;
  94         }
  95
  96         assert(u->memchunk.memblock && u->memchunk.memblock->data && u->memchunk.length && u->memchunk.memblock->length && (u->memchunk.length % u->frame_size) == 0);
  97
  98         if ((frames = snd_pcm_readi(u->pcm_handle, u->memchunk.memblock->data + u->memchunk.index, u->memchunk.length / u->frame_size)) < 0) {
  99             if (frames == -EAGAIN)
 100                 return;
 101
 102             if (frames == -EPIPE) {
 103                 xrun_recovery(u);
 104                 continue;
 105             }
 106
 107             fprintf(stderr, "snd_pcm_readi() failed: %s\n", strerror(-frames));
 108             return;
 109         }
 110
 111         l = frames * u->frame_size;
 112
 113         post_memchunk = u->memchunk;
 114         post_memchunk.length = l;
 115
 116         pa_source_post(u->source, &post_memchunk);
 117
 118         u->memchunk.index += l;
 119         u->memchunk.length -= l;
 120
 121         if (u->memchunk.length == 0) {
 122             pa_memblock_unref(u->memchunk.memblock);
 123             u->memchunk.memblock = NULL;
 124             u->memchunk.index = u->memchunk.length = 0;
 125         }
 126
 127         break;
 128     }
 129 }
 130
 131 static void io_callback(struct pa_mainloop_api*a, void *id, int fd, enum pa_mainloop_api_io_events events, void *userdata) {
 132     struct userdata *u = userdata;
 133     assert(u && a && id);
 134
 135     if (snd_pcm_state(u->pcm_handle) == SND_PCM_STATE_XRUN)
 136         xrun_recovery(u);
 137
 138     do_read(u);
 139 }
 140
 141 int pa_module_init(struct pa_core *c, struct pa_module*m) {
 142     struct pa_modargs *ma = NULL;
 143     int ret = -1;
 144     struct userdata *u = NULL;
 145     const char *dev;
 146     struct pa_sample_spec ss;
 147     unsigned periods, fragsize;
 148     snd_pcm_uframes_t buffer_size;
 149     size_t frame_size;
 150
 151     if (!(ma = pa_modargs_new(m->argument, valid_modargs))) {
 152         fprintf(stderr, __FILE__": failed to parse module arguments\n");
 153         goto fail;
 154     }
 155
 156     ss = c->default_sample_spec;
 157     if (pa_modargs_get_sample_spec(ma, &ss) < 0) {
 158         fprintf(stderr, __FILE__": failed to parse sample specification\n");
 159         goto fail;
 160     }
 161     frame_size = pa_frame_size(&ss);
 162
 163     periods = 12;
 164     fragsize = 1024;
 165     if (pa_modargs_get_value_u32(ma, "fragments", &periods) < 0 || pa_modargs_get_value_u32(ma, "fragment_size", &fragsize) < 0) {
 166         fprintf(stderr, __FILE__": failed to parse buffer metrics\n");
 167         goto fail;
 168     }
 169     buffer_size = fragsize/frame_size*periods;
 170
 171     u = pa_xmalloc0(sizeof(struct userdata));
 172     m->userdata = u;
 173     u->module = m;
 174
 175     if (snd_pcm_open(&u->pcm_handle, dev = pa_modargs_get_value(ma, "device", DEFAULT_DEVICE), SND_PCM_STREAM_CAPTURE, SND_PCM_NONBLOCK) < 0) {
 176         fprintf(stderr, __FILE__": Error opening PCM device %s\n", dev);
 177         goto fail;
 178     }
 179
 180     if (pa_alsa_set_hw_params(u->pcm_handle, &ss, &periods, &buffer_size) < 0) {
 181         fprintf(stderr, __FILE__": Failed to set hardware parameters\n");
 182         goto fail;
 183     }
 184
 185     u->source = pa_source_new(c, pa_modargs_get_value(ma, "source_name", DEFAULT_SOURCE_NAME), 0, &ss);
 186     assert(u->source);
 187
 188     u->source->userdata = u;
 189     pa_source_set_owner(u->source, m);
 190     u->source->description = pa_sprintf_malloc("Advanced Linux Sound Architecture PCM on '%s'", dev);
 191
 192     if (pa_create_io_sources(u->pcm_handle, c->mainloop, &u->io_sources, &u->n_io_sources, io_callback, u) < 0) {
 193         fprintf(stderr, __FILE__": failed to obtain file descriptors\n");
 194         goto fail;
 195     }
 196
 197     u->frame_size = frame_size;
 198     u->fragment_size = buffer_size*u->frame_size/periods;
 199
 200     fprintf(stderr, __FILE__": using %u fragments of size %u bytes.\n", periods, u->fragment_size);
 201
 202     u->memchunk.memblock = NULL;
 203     u->memchunk.index = u->memchunk.length = 0;
 204
 205     snd_pcm_start(u->pcm_handle);
 206
 207     ret = 0;
 208
 209 finish:
 210      if (ma)
 211          pa_modargs_free(ma);
 212
 213     return ret;
 214
 215 fail:
 216
 217     if (u)
 218         pa_module_done(c, m);
 219
 220     goto finish;
 221 }
 222
 223 void pa_module_done(struct pa_core *c, struct pa_module*m) {
 224     struct userdata *u;
 225     assert(c && m);
 226
 227     if (!(u = m->userdata))
 228         return;
 229
 230     if (u->source)
 231         pa_source_free(u->source);
 232
 233     if (u->io_sources)
 234         pa_free_io_sources(c->mainloop, u->io_sources, u->n_io_sources);
 235
 236     if (u->pcm_handle) {
 237         snd_pcm_drop(u->pcm_handle);
 238         snd_pcm_close(u->pcm_handle);
 239     }
 240
 241     if (u->memchunk.memblock)
 242         pa_memblock_unref(u->memchunk.memblock);
 243
 244     pa_xfree(u);
 245 }
 246