code.delx.au - pulseaudio/blob - src/modules/module-null-sink.c

   1 /* $Id$ */
   2
   3 /***
   4   This file is part of PulseAudio.
   5
   6   Copyright 2004-2006 Lennart Poettering
   7
   8   PulseAudio is free software; you can redistribute it and/or modify
   9   it under the terms of the GNU Lesser General Public License as published
  10   by the Free Software Foundation; either version 2 of the License,
  11   or (at your option) any later version.
  12
  13   PulseAudio is distributed in the hope that it will be useful, but
  14   WITHOUT ANY WARRANTY; without even the implied warranty of
  15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  16   General Public License for more details.
  17
  18   You should have received a copy of the GNU Lesser General Public License
  19   along with PulseAudio; if not, write to the Free Software
  20   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  21   USA.
  22 ***/
  23
  24 #ifdef HAVE_CONFIG_H
  25 #include <config.h>
  26 #endif
  27
  28 #include <stdlib.h>
  29 #include <sys/stat.h>
  30 #include <stdio.h>
  31 #include <errno.h>
  32 #include <string.h>
  33 #include <fcntl.h>
  34 #include <unistd.h>
  35 #include <limits.h>
  36 #include <sys/poll.h>
  37
  38 #include <pulse/timeval.h>
  39 #include <pulse/xmalloc.h>
  40
  41 #include <pulsecore/macro.h>
  42 #include <pulsecore/sink.h>
  43 #include <pulsecore/module.h>
  44 #include <pulsecore/core-util.h>
  45 #include <pulsecore/core-error.h>
  46 #include <pulsecore/modargs.h>
  47 #include <pulsecore/log.h>
  48 #include <pulsecore/thread.h>
  49 #include <pulsecore/thread-mq.h>
  50
  51 #include "module-null-sink-symdef.h"
  52
  53 PA_MODULE_AUTHOR("Lennart Poettering")
  54 PA_MODULE_DESCRIPTION("Clocked NULL sink")
  55 PA_MODULE_VERSION(PACKAGE_VERSION)
  56 PA_MODULE_USAGE(
  57         "format=<sample format> "
  58         "channels=<number of channels> "
  59         "rate=<sample rate> "
  60         "sink_name=<name of sink>"
  61         "channel_map=<channel map>"
  62         "description=<description for the sink>")
  63
  64 #define DEFAULT_SINK_NAME "null"
  65
  66 struct userdata {
  67     pa_core *core;
  68     pa_module *module;
  69     pa_sink *sink;
  70     pa_thread *thread;
  71     pa_thread_mq thread_mq;
  72     size_t block_size;
  73
  74     struct timeval timestamp;
  75 };
  76
  77 static const char* const valid_modargs[] = {
  78     "rate",
  79     "format",
  80     "channels",
  81     "sink_name",
  82     "channel_map",
  83     "description",
  84     NULL
  85 };
  86
  87 static int sink_process_msg(pa_msgobject *o, int code, void *data, int64_t offset, pa_memchunk *chunk) {
  88     struct userdata *u = PA_SINK(o)->userdata;
  89
  90     switch (code) {
  91         case PA_SINK_MESSAGE_SET_STATE:
  92
  93             if (PA_PTR_TO_UINT(data) == PA_SINK_RUNNING)
  94                 pa_gettimeofday(&u->timestamp);
  95
  96             break;
  97
  98         case PA_SINK_MESSAGE_GET_LATENCY: {
  99             struct timeval now;
 100
 101             pa_gettimeofday(&now);
 102
 103             if (pa_timeval_cmp(&u->timestamp, &now) > 0)
 104                 *((pa_usec_t*) data) = 0;
 105             else
 106                 *((pa_usec_t*) data) = pa_timeval_diff(&u->timestamp, &now);
 107             break;
 108         }
 109     }
 110
 111     return pa_sink_process_msg(o, code, data, offset, chunk);
 112 }
 113
 114 static void thread_func(void *userdata) {
 115     struct userdata *u = userdata;
 116     struct pollfd pollfd;
 117
 118     pa_assert(u);
 119
 120     pa_log_debug("Thread starting up");
 121
 122     pa_thread_mq_install(&u->thread_mq);
 123
 124     pa_gettimeofday(&u->timestamp);
 125
 126     memset(&pollfd, 0, sizeof(pollfd));
 127     pollfd.fd = pa_asyncmsgq_get_fd(u->thread_mq.inq);
 128     pollfd.events = POLLIN;
 129
 130     for (;;) {
 131         pa_msgobject *object;
 132         int code;
 133         void *data;
 134         pa_memchunk chunk;
 135         int r, timeout;
 136         struct timeval now;
 137         int64_t offset;
 138
 139         /* Check whether there is a message for us to process */
 140         if (pa_asyncmsgq_get(u->thread_mq.inq, &object, &code, &data, &offset, &chunk, 0) == 0) {
 141             int ret;
 142
 143             if (!object && code == PA_MESSAGE_SHUTDOWN) {
 144                 pa_asyncmsgq_done(u->thread_mq.inq, 0);
 145                 goto finish;
 146             }
 147
 148             ret = pa_asyncmsgq_dispatch(object, code, data, offset, &chunk);
 149             pa_asyncmsgq_done(u->thread_mq.inq, ret);
 150             continue;
 151         }
 152
 153         /* Render some data and drop it immediately */
 154         if (u->sink->thread_info.state == PA_SINK_RUNNING) {
 155             pa_gettimeofday(&now);
 156
 157             if (pa_timeval_cmp(&u->timestamp, &now) <= 0) {
 158
 159                 pa_sink_render(u->sink, u->block_size, &chunk);
 160                 pa_memblock_unref(chunk.memblock);
 161
 162                 pa_timeval_add(&u->timestamp, pa_bytes_to_usec(chunk.length, &u->sink->sample_spec));
 163                 continue;
 164             }
 165
 166             timeout = pa_timeval_diff(&u->timestamp, &now)/1000;
 167
 168             if (timeout < 1)
 169                 timeout = 1;
 170         } else
 171             timeout = -1;
 172
 173         /* Hmm, nothing to do. Let's sleep */
 174
 175         if (pa_asyncmsgq_before_poll(u->thread_mq.inq) < 0)
 176             continue;
 177
 178         r = poll(&pollfd, 1, timeout);
 179         pa_asyncmsgq_after_poll(u->thread_mq.inq);
 180
 181         if (r < 0) {
 182             if (errno == EINTR) {
 183                 pollfd.revents = 0;
 184                 continue;
 185             }
 186
 187             pa_log("poll() failed: %s", pa_cstrerror(errno));
 188             goto fail;
 189         }
 190
 191         pa_assert(r == 0 || pollfd.revents == POLLIN);
 192     }
 193
 194 fail:
 195     /* We have to continue processing messages until we receive the
 196      * SHUTDOWN message */
 197     pa_asyncmsgq_post(u->thread_mq.outq, PA_MSGOBJECT(u->core), PA_CORE_MESSAGE_UNLOAD_MODULE, u->module, 0, NULL, NULL);
 198     pa_asyncmsgq_wait_for(u->thread_mq.inq, PA_MESSAGE_SHUTDOWN);
 199
 200 finish:
 201     pa_log_debug("Thread shutting down");
 202 }
 203
 204 int pa__init(pa_module*m) {
 205     struct userdata *u = NULL;
 206     pa_sample_spec ss;
 207     pa_channel_map map;
 208     pa_modargs *ma = NULL;
 209
 210     pa_assert(m);
 211
 212     if (!(ma = pa_modargs_new(m->argument, valid_modargs))) {
 213         pa_log("Failed to parse module arguments.");
 214         goto fail;
 215     }
 216
 217     ss = m->core->default_sample_spec;
 218     if (pa_modargs_get_sample_spec_and_channel_map(ma, &ss, &map, PA_CHANNEL_MAP_DEFAULT) < 0) {
 219         pa_log("Invalid sample format specification or channel map");
 220         goto fail;
 221     }
 222
 223     u = pa_xnew0(struct userdata, 1);
 224     u->core = m->core;
 225     u->module = m;
 226     m->userdata = u;
 227
 228     pa_thread_mq_init(&u->thread_mq, m->core->mainloop);
 229
 230     if (!(u->sink = pa_sink_new(m->core, __FILE__, pa_modargs_get_value(ma, "sink_name", DEFAULT_SINK_NAME), 0, &ss, &map))) {
 231         pa_log("Failed to create sink.");
 232         goto fail;
 233     }
 234
 235     u->sink->parent.process_msg = sink_process_msg;
 236     u->sink->userdata = u;
 237
 238     pa_sink_set_module(u->sink, m);
 239     pa_sink_set_asyncmsgq(u->sink, u->thread_mq.inq);
 240     pa_sink_set_description(u->sink, pa_modargs_get_value(ma, "description", "NULL sink"));
 241
 242     u->block_size = pa_bytes_per_second(&ss) / 20; /* 50 ms */
 243     if (u->block_size <= 0)
 244         u->block_size = pa_frame_size(&ss);
 245
 246     if (!(u->thread = pa_thread_new(thread_func, u))) {
 247         pa_log("Failed to create thread.");
 248         goto fail;
 249     }
 250
 251     pa_modargs_free(ma);
 252
 253     return 0;
 254
 255 fail:
 256     if (ma)
 257         pa_modargs_free(ma);
 258
 259     pa__done(m);
 260
 261     return -1;
 262 }
 263
 264 void pa__done(pa_module*m) {
 265     struct userdata *u;
 266
 267     pa_assert(m);
 268
 269     if (!(u = m->userdata))
 270         return;
 271
 272     if (u->sink)
 273         pa_sink_disconnect(u->sink);
 274
 275     if (u->thread) {
 276         pa_asyncmsgq_send(u->thread_mq.inq, NULL, PA_MESSAGE_SHUTDOWN, NULL, 0, NULL);
 277         pa_thread_free(u->thread);
 278     }
 279
 280     pa_thread_mq_done(&u->thread_mq);
 281
 282     if (u->sink)
 283         pa_sink_unref(u->sink);
 284
 285     pa_xfree(u);
 286 }