code.delx.au - pulseaudio/blob - src/modules/module-sine-source.c

   1 /***
   2   This file is part of PulseAudio.
   3
   4   Copyright 2008 Lennart Poettering
   5
   6   PulseAudio 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 2.1 of the License,
   9   or (at your option) any later version.
  10
  11   PulseAudio 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 PulseAudio; 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 <stdlib.h>
  27 #include <sys/stat.h>
  28 #include <stdio.h>
  29 #include <errno.h>
  30 #include <string.h>
  31 #include <fcntl.h>
  32 #include <unistd.h>
  33 #include <limits.h>
  34 #include <sys/ioctl.h>
  35 #include <sys/poll.h>
  36
  37 #include <pulse/xmalloc.h>
  38 #include <pulse/timeval.h>
  39
  40 #include <pulsecore/core-error.h>
  41 #include <pulsecore/source.h>
  42 #include <pulsecore/module.h>
  43 #include <pulsecore/core-util.h>
  44 #include <pulsecore/modargs.h>
  45 #include <pulsecore/log.h>
  46 #include <pulsecore/thread.h>
  47 #include <pulsecore/thread-mq.h>
  48 #include <pulsecore/rtpoll.h>
  49 #include <pulsecore/rtclock.h>
  50
  51 #include "module-sine-source-symdef.h"
  52
  53 PA_MODULE_AUTHOR("Lennart Poettering");
  54 PA_MODULE_DESCRIPTION("Sine wave generator source");
  55 PA_MODULE_VERSION(PACKAGE_VERSION);
  56 PA_MODULE_LOAD_ONCE(FALSE);
  57 PA_MODULE_USAGE(
  58         "source_name=<name for the source> "
  59         "source_properties=<properties for the source> "
  60         "rate=<sample rate> "
  61         "frequency=<frequency in Hz>");
  62
  63 #define DEFAULT_SOURCE_NAME "sine_input"
  64 #define BLOCK_USEC (PA_USEC_PER_SEC * 2)
  65
  66 struct userdata {
  67     pa_core *core;
  68     pa_module *module;
  69     pa_source *source;
  70
  71     pa_thread *thread;
  72     pa_thread_mq thread_mq;
  73     pa_rtpoll *rtpoll;
  74
  75     pa_memchunk memchunk;
  76     size_t peek_index;
  77
  78     pa_usec_t block_usec; /* how much to push at once */
  79     pa_usec_t timestamp;  /* when to push next */
  80 };
  81
  82 static const char* const valid_modargs[] = {
  83     "source_name",
  84     "source_properties",
  85     "rate",
  86     "frequency",
  87     NULL
  88 };
  89
  90 static int source_process_msg(
  91         pa_msgobject *o,
  92         int code,
  93         void *data,
  94         int64_t offset,
  95         pa_memchunk *chunk) {
  96
  97     struct userdata *u = PA_SOURCE(o)->userdata;
  98
  99     switch (code) {
 100
 101         case PA_SOURCE_MESSAGE_SET_STATE:
 102
 103             if (PA_PTR_TO_UINT(data) == PA_SOURCE_RUNNING)
 104                 u->timestamp = pa_rtclock_usec();
 105
 106             break;
 107
 108         case PA_SOURCE_MESSAGE_GET_LATENCY: {
 109             pa_usec_t now, left_to_fill;
 110
 111             now = pa_rtclock_usec();
 112             left_to_fill = u->timestamp > now ? u->timestamp - now : 0ULL;
 113
 114             *((pa_usec_t*) data) = u->block_usec > left_to_fill ? u->block_usec - left_to_fill : 0ULL;
 115
 116             return 0;
 117         }
 118     }
 119
 120     return pa_source_process_msg(o, code, data, offset, chunk);
 121 }
 122
 123 static void source_update_requested_latency_cb(pa_source *s) {
 124     struct userdata *u;
 125
 126     pa_source_assert_ref(s);
 127     pa_assert_se(u = s->userdata);
 128
 129     u->block_usec = pa_source_get_requested_latency_within_thread(s);
 130
 131     if (u->block_usec == (pa_usec_t) -1)
 132         u->block_usec = s->thread_info.max_latency;
 133
 134     pa_log_debug("new block msec = %lu", (unsigned long) (u->block_usec / PA_USEC_PER_MSEC));
 135 }
 136
 137 static void process_render(struct userdata *u, pa_usec_t now) {
 138     pa_assert(u);
 139
 140     while (u->timestamp < now + u->block_usec) {
 141         pa_memchunk chunk;
 142         size_t k;
 143
 144         k = pa_usec_to_bytes_round_up(now + u->block_usec - u->timestamp, &u->source->sample_spec);
 145
 146         chunk = u->memchunk;
 147         chunk.index += u->peek_index;
 148         chunk.length = PA_MIN(chunk.length - u->peek_index, k);
 149
 150 /*         pa_log_debug("posting %lu", (unsigned long) chunk.length); */
 151         pa_source_post(u->source, &chunk);
 152
 153         u->peek_index += chunk.length;
 154         while (u->peek_index >= u->memchunk.length)
 155             u->peek_index -= u->memchunk.length;
 156
 157         u->timestamp += pa_bytes_to_usec(chunk.length, &u->source->sample_spec);
 158     }
 159 }
 160
 161 static void thread_func(void *userdata) {
 162     struct userdata *u = userdata;
 163
 164     pa_assert(u);
 165
 166     pa_log_debug("Thread starting up");
 167
 168     pa_thread_mq_install(&u->thread_mq);
 169
 170     u->timestamp = pa_rtclock_usec();
 171
 172     for (;;) {
 173         int ret;
 174
 175         if (PA_SOURCE_IS_OPENED(u->source->thread_info.state)) {
 176             pa_usec_t now;
 177
 178             now = pa_rtclock_usec();
 179
 180             if (u->timestamp <= now)
 181                 process_render(u, now);
 182
 183             pa_rtpoll_set_timer_absolute(u->rtpoll, u->timestamp);
 184         } else
 185             pa_rtpoll_set_timer_disabled(u->rtpoll);
 186
 187         /* Hmm, nothing to do. Let's sleep */
 188         if ((ret = pa_rtpoll_run(u->rtpoll, TRUE)) < 0)
 189             goto fail;
 190
 191         if (ret == 0)
 192             goto finish;
 193     }
 194
 195 fail:
 196     /* If this was no regular exit from the loop we have to continue
 197      * processing messages until we received PA_MESSAGE_SHUTDOWN */
 198     pa_asyncmsgq_post(u->thread_mq.outq, PA_MSGOBJECT(u->core), PA_CORE_MESSAGE_UNLOAD_MODULE, u->module, 0, NULL, NULL);
 199     pa_asyncmsgq_wait_for(u->thread_mq.inq, PA_MESSAGE_SHUTDOWN);
 200
 201 finish:
 202     pa_log_debug("Thread shutting down");
 203 }
 204
 205 int pa__init(pa_module*m) {
 206     struct userdata *u;
 207     pa_modargs *ma;
 208     pa_source_new_data data;
 209     uint32_t frequency;
 210     pa_sample_spec ss;
 211
 212     pa_assert(m);
 213
 214     if (!(ma = pa_modargs_new(m->argument, valid_modargs))) {
 215         pa_log("failed to parse module arguments.");
 216         goto fail;
 217     }
 218
 219     ss.format = PA_SAMPLE_FLOAT32;
 220     ss.channels = 1;
 221     ss.rate = 44100;
 222
 223     if (pa_modargs_get_value_u32(ma, "rate", &ss.rate) < 0 || ss.rate <= 1) {
 224         pa_log("Invalid rate specification");
 225         goto fail;
 226     }
 227
 228     frequency = 440;
 229     if (pa_modargs_get_value_u32(ma, "frequency", &frequency) < 0 || frequency < 1 || frequency > ss.rate/2) {
 230         pa_log("Invalid frequency specification");
 231         goto fail;
 232     }
 233
 234     m->userdata = u = pa_xnew0(struct userdata, 1);
 235     u->core = m->core;
 236     u->module = m;
 237     u->rtpoll = pa_rtpoll_new();
 238     pa_thread_mq_init(&u->thread_mq, m->core->mainloop, u->rtpoll);
 239
 240     u->peek_index = 0;
 241     pa_memchunk_sine(&u->memchunk, m->core->mempool, ss.rate, frequency);
 242
 243     pa_source_new_data_init(&data);
 244     data.driver = __FILE__;
 245     data.module = m;
 246     pa_source_new_data_set_name(&data, pa_modargs_get_value(ma, "source_name", DEFAULT_SOURCE_NAME));
 247     pa_proplist_setf(data.proplist, PA_PROP_DEVICE_DESCRIPTION, "Sine source at %u Hz", (unsigned) frequency);
 248     pa_proplist_sets(data.proplist, PA_PROP_DEVICE_CLASS, "abstract");
 249     pa_proplist_setf(data.proplist, "sine.hz", "%u", frequency);
 250     pa_source_new_data_set_sample_spec(&data, &ss);
 251
 252     if (pa_modargs_get_proplist(ma, "source_properties", data.proplist, PA_UPDATE_REPLACE) < 0) {
 253         pa_log("Invalid properties");
 254         pa_source_new_data_done(&data);
 255         goto fail;
 256     }
 257
 258     u->source = pa_source_new(m->core, &data, PA_SOURCE_LATENCY);
 259     pa_source_new_data_done(&data);
 260
 261     if (!u->source) {
 262         pa_log("Failed to create source.");
 263         goto fail;
 264     }
 265
 266     u->source->parent.process_msg = source_process_msg;
 267     u->source->update_requested_latency = source_update_requested_latency_cb;
 268     u->source->userdata = u;
 269
 270     u->block_usec = BLOCK_USEC;
 271
 272     pa_source_set_asyncmsgq(u->source, u->thread_mq.inq);
 273     pa_source_set_rtpoll(u->source, u->rtpoll);
 274     pa_source_set_fixed_latency(u->source, u->block_usec);
 275
 276     if (!(u->thread = pa_thread_new(thread_func, u))) {
 277         pa_log("Failed to create thread.");
 278         goto fail;
 279     }
 280
 281     pa_source_put(u->source);
 282
 283     pa_modargs_free(ma);
 284
 285     return 0;
 286
 287 fail:
 288     if (ma)
 289         pa_modargs_free(ma);
 290
 291     pa__done(m);
 292
 293     return -1;
 294 }
 295
 296 int pa__get_n_used(pa_module *m) {
 297     struct userdata *u;
 298
 299     pa_assert(m);
 300     pa_assert_se(u = m->userdata);
 301
 302     return pa_source_linked_by(u->source);
 303 }
 304
 305 void pa__done(pa_module*m) {
 306     struct userdata *u;
 307
 308     pa_assert(m);
 309
 310     if (!(u = m->userdata))
 311         return;
 312
 313     if (u->source)
 314         pa_source_unlink(u->source);
 315
 316     if (u->thread) {
 317         pa_asyncmsgq_send(u->thread_mq.inq, NULL, PA_MESSAGE_SHUTDOWN, NULL, 0, NULL);
 318         pa_thread_free(u->thread);
 319     }
 320
 321     pa_thread_mq_done(&u->thread_mq);
 322
 323     if (u->source)
 324         pa_source_unref(u->source);
 325
 326     if (u->memchunk.memblock)
 327         pa_memblock_unref(u->memchunk.memblock);
 328
 329     if (u->rtpoll)
 330         pa_rtpoll_free(u->rtpoll);
 331
 332     pa_xfree(u);
 333 }