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