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/rtclock.h>
  38 #include <pulse/timeval.h>
  39 #include <pulse/xmalloc.h>
  40
  41 #include <pulsecore/core-error.h>
  42 #include <pulsecore/source.h>
  43 #include <pulsecore/module.h>
  44 #include <pulsecore/core-rtclock.h>
  45 #include <pulsecore/core-util.h>
  46 #include <pulsecore/modargs.h>
  47 #include <pulsecore/log.h>
  48 #include <pulsecore/thread.h>
  49 #include <pulsecore/thread-mq.h>
  50 #include <pulsecore/rtpoll.h>
  51
  52 #include "module-sine-source-symdef.h"
  53
  54 PA_MODULE_AUTHOR("Lennart Poettering");
  55 PA_MODULE_DESCRIPTION("Sine wave generator source");
  56 PA_MODULE_VERSION(PACKAGE_VERSION);
  57 PA_MODULE_LOAD_ONCE(FALSE);
  58 PA_MODULE_USAGE(
  59         "source_name=<name for the source> "
  60         "source_properties=<properties for the source> "
  61         "rate=<sample rate> "
  62         "frequency=<frequency in Hz>");
  63
  64 #define DEFAULT_SOURCE_NAME "sine_input"
  65 #define BLOCK_USEC (PA_USEC_PER_SEC * 2)
  66
  67 struct userdata {
  68     pa_core *core;
  69     pa_module *module;
  70     pa_source *source;
  71
  72     pa_thread *thread;
  73     pa_thread_mq thread_mq;
  74     pa_rtpoll *rtpoll;
  75
  76     pa_memchunk memchunk;
  77     size_t peek_index;
  78
  79     pa_usec_t block_usec; /* how much to push at once */
  80     pa_usec_t timestamp;  /* when to push next */
  81 };
  82
  83 static const char* const valid_modargs[] = {
  84     "source_name",
  85     "source_properties",
  86     "rate",
  87     "frequency",
  88     NULL
  89 };
  90
  91 static int source_process_msg(
  92         pa_msgobject *o,
  93         int code,
  94         void *data,
  95         int64_t offset,
  96         pa_memchunk *chunk) {
  97
  98     struct userdata *u = PA_SOURCE(o)->userdata;
  99
 100     switch (code) {
 101
 102         case PA_SOURCE_MESSAGE_SET_STATE:
 103
 104             if (PA_PTR_TO_UINT(data) == PA_SOURCE_RUNNING)
 105                 u->timestamp = pa_rtclock_now();
 106
 107             break;
 108
 109         case PA_SOURCE_MESSAGE_GET_LATENCY: {
 110             pa_usec_t now, left_to_fill;
 111
 112             now = pa_rtclock_now();
 113             left_to_fill = u->timestamp > now ? u->timestamp - now : 0ULL;
 114
 115             *((pa_usec_t*) data) = u->block_usec > left_to_fill ? u->block_usec - left_to_fill : 0ULL;
 116
 117             return 0;
 118         }
 119     }
 120
 121     return pa_source_process_msg(o, code, data, offset, chunk);
 122 }
 123
 124 static void source_update_requested_latency_cb(pa_source *s) {
 125     struct userdata *u;
 126
 127     pa_source_assert_ref(s);
 128     pa_assert_se(u = s->userdata);
 129
 130     u->block_usec = pa_source_get_requested_latency_within_thread(s);
 131
 132     if (u->block_usec == (pa_usec_t) -1)
 133         u->block_usec = s->thread_info.max_latency;
 134
 135     pa_log_debug("new block msec = %lu", (unsigned long) (u->block_usec / PA_USEC_PER_MSEC));
 136 }
 137
 138 static void process_render(struct userdata *u, pa_usec_t now) {
 139     pa_assert(u);
 140
 141     while (u->timestamp < now + u->block_usec) {
 142         pa_memchunk chunk;
 143         size_t k;
 144
 145         k = pa_usec_to_bytes_round_up(now + u->block_usec - u->timestamp, &u->source->sample_spec);
 146
 147         chunk = u->memchunk;
 148         chunk.index += u->peek_index;
 149         chunk.length = PA_MIN(chunk.length - u->peek_index, k);
 150
 151 /*         pa_log_debug("posting %lu", (unsigned long) chunk.length); */
 152         pa_source_post(u->source, &chunk);
 153
 154         u->peek_index += chunk.length;
 155         while (u->peek_index >= u->memchunk.length)
 156             u->peek_index -= u->memchunk.length;
 157
 158         u->timestamp += pa_bytes_to_usec(chunk.length, &u->source->sample_spec);
 159     }
 160 }
 161
 162 static void thread_func(void *userdata) {
 163     struct userdata *u = userdata;
 164
 165     pa_assert(u);
 166
 167     pa_log_debug("Thread starting up");
 168
 169     pa_thread_mq_install(&u->thread_mq);
 170
 171     u->timestamp = pa_rtclock_now();
 172
 173     for (;;) {
 174         int ret;
 175
 176         if (PA_SOURCE_IS_OPENED(u->source->thread_info.state)) {
 177             pa_usec_t now;
 178
 179             now = pa_rtclock_now();
 180
 181             if (u->timestamp <= now)
 182                 process_render(u, now);
 183
 184             pa_rtpoll_set_timer_absolute(u->rtpoll, u->timestamp);
 185         } else
 186             pa_rtpoll_set_timer_disabled(u->rtpoll);
 187
 188         /* Hmm, nothing to do. Let's sleep */
 189         if ((ret = pa_rtpoll_run(u->rtpoll, TRUE)) < 0)
 190             goto fail;
 191
 192         if (ret == 0)
 193             goto finish;
 194     }
 195
 196 fail:
 197     /* If this was no regular exit from the loop we have to continue
 198      * processing messages until we received PA_MESSAGE_SHUTDOWN */
 199     pa_asyncmsgq_post(u->thread_mq.outq, PA_MSGOBJECT(u->core), PA_CORE_MESSAGE_UNLOAD_MODULE, u->module, 0, NULL, NULL);
 200     pa_asyncmsgq_wait_for(u->thread_mq.inq, PA_MESSAGE_SHUTDOWN);
 201
 202 finish:
 203     pa_log_debug("Thread shutting down");
 204 }
 205
 206 int pa__init(pa_module*m) {
 207     struct userdata *u;
 208     pa_modargs *ma;
 209     pa_source_new_data data;
 210     uint32_t frequency;
 211     pa_sample_spec ss;
 212
 213     pa_assert(m);
 214
 215     if (!(ma = pa_modargs_new(m->argument, valid_modargs))) {
 216         pa_log("failed to parse module arguments.");
 217         goto fail;
 218     }
 219
 220     ss.format = PA_SAMPLE_FLOAT32;
 221     ss.channels = 1;
 222     ss.rate = 44100;
 223
 224     if (pa_modargs_get_value_u32(ma, "rate", &ss.rate) < 0 || ss.rate <= 1) {
 225         pa_log("Invalid rate specification");
 226         goto fail;
 227     }
 228
 229     frequency = 440;
 230     if (pa_modargs_get_value_u32(ma, "frequency", &frequency) < 0 || frequency < 1 || frequency > ss.rate/2) {
 231         pa_log("Invalid frequency specification");
 232         goto fail;
 233     }
 234
 235     m->userdata = u = pa_xnew0(struct userdata, 1);
 236     u->core = m->core;
 237     u->module = m;
 238     u->rtpoll = pa_rtpoll_new();
 239     pa_thread_mq_init(&u->thread_mq, m->core->mainloop, u->rtpoll);
 240
 241     u->peek_index = 0;
 242     pa_memchunk_sine(&u->memchunk, m->core->mempool, ss.rate, frequency);
 243
 244     pa_source_new_data_init(&data);
 245     data.driver = __FILE__;
 246     data.module = m;
 247     pa_source_new_data_set_name(&data, pa_modargs_get_value(ma, "source_name", DEFAULT_SOURCE_NAME));
 248     pa_proplist_setf(data.proplist, PA_PROP_DEVICE_DESCRIPTION, "Sine source at %u Hz", (unsigned) frequency);
 249     pa_proplist_sets(data.proplist, PA_PROP_DEVICE_CLASS, "abstract");
 250     pa_proplist_setf(data.proplist, "sine.hz", "%u", frequency);
 251     pa_source_new_data_set_sample_spec(&data, &ss);
 252
 253     if (pa_modargs_get_proplist(ma, "source_properties", data.proplist, PA_UPDATE_REPLACE) < 0) {
 254         pa_log("Invalid properties");
 255         pa_source_new_data_done(&data);
 256         goto fail;
 257     }
 258
 259     u->source = pa_source_new(m->core, &data, PA_SOURCE_LATENCY);
 260     pa_source_new_data_done(&data);
 261
 262     if (!u->source) {
 263         pa_log("Failed to create source.");
 264         goto fail;
 265     }
 266
 267     u->source->parent.process_msg = source_process_msg;
 268     u->source->update_requested_latency = source_update_requested_latency_cb;
 269     u->source->userdata = u;
 270
 271     u->block_usec = BLOCK_USEC;
 272
 273     pa_source_set_asyncmsgq(u->source, u->thread_mq.inq);
 274     pa_source_set_rtpoll(u->source, u->rtpoll);
 275     pa_source_set_fixed_latency(u->source, u->block_usec);
 276
 277     if (!(u->thread = pa_thread_new(thread_func, u))) {
 278         pa_log("Failed to create thread.");
 279         goto fail;
 280     }
 281
 282     pa_source_put(u->source);
 283
 284     pa_modargs_free(ma);
 285
 286     return 0;
 287
 288 fail:
 289     if (ma)
 290         pa_modargs_free(ma);
 291
 292     pa__done(m);
 293
 294     return -1;
 295 }
 296
 297 int pa__get_n_used(pa_module *m) {
 298     struct userdata *u;
 299
 300     pa_assert(m);
 301     pa_assert_se(u = m->userdata);
 302
 303     return pa_source_linked_by(u->source);
 304 }
 305
 306 void pa__done(pa_module*m) {
 307     struct userdata *u;
 308
 309     pa_assert(m);
 310
 311     if (!(u = m->userdata))
 312         return;
 313
 314     if (u->source)
 315         pa_source_unlink(u->source);
 316
 317     if (u->thread) {
 318         pa_asyncmsgq_send(u->thread_mq.inq, NULL, PA_MESSAGE_SHUTDOWN, NULL, 0, NULL);
 319         pa_thread_free(u->thread);
 320     }
 321
 322     pa_thread_mq_done(&u->thread_mq);
 323
 324     if (u->source)
 325         pa_source_unref(u->source);
 326
 327     if (u->memchunk.memblock)
 328         pa_memblock_unref(u->memchunk.memblock);
 329
 330     if (u->rtpoll)
 331         pa_rtpoll_free(u->rtpoll);
 332
 333     pa_xfree(u);
 334 }