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
  50 #include "module-null-sink-symdef.h"
  51
  52 PA_MODULE_AUTHOR("Lennart Poettering")
  53 PA_MODULE_DESCRIPTION("Clocked NULL sink")
  54 PA_MODULE_VERSION(PACKAGE_VERSION)
  55 PA_MODULE_USAGE(
  56         "format=<sample format> "
  57         "channels=<number of channels> "
  58         "rate=<sample rate> "
  59         "sink_name=<name of sink>"
  60         "channel_map=<channel map>"
  61         "description=<description for the sink>")
  62
  63 #define DEFAULT_SINK_NAME "null"
  64
  65 struct userdata {
  66     pa_core *core;
  67     pa_module *module;
  68     pa_sink *sink;
  69     pa_thread *thread;
  70     pa_asyncmsgq *asyncmsgq;
  71     size_t block_size;
  72
  73     struct timeval timestamp;
  74 };
  75
  76 static const char* const valid_modargs[] = {
  77     "rate",
  78     "format",
  79     "channels",
  80     "sink_name",
  81     "channel_map",
  82     "description",
  83     NULL
  84 };
  85
  86 static int sink_process_msg(pa_msgobject *o, int code, void *data, pa_memchunk *chunk) {
  87     struct userdata *u = PA_SINK(o)->userdata;
  88
  89     switch (code) {
  90         case PA_SINK_MESSAGE_SET_STATE:
  91
  92             if (PA_PTR_TO_UINT(data) == PA_SINK_RUNNING)
  93                 pa_gettimeofday(&u->timestamp);
  94
  95             break;
  96
  97         case PA_SINK_MESSAGE_GET_LATENCY: {
  98             struct timeval now;
  99
 100             pa_gettimeofday(&now);
 101
 102             if (pa_timeval_cmp(&u->timestamp, &now) > 0)
 103                 *((pa_usec_t*) data) = 0;
 104             else
 105                 *((pa_usec_t*) data) = pa_timeval_diff(&u->timestamp, &now);
 106             break;
 107         }
 108     }
 109
 110     return pa_sink_process_msg(o, code, data, chunk);
 111 }
 112
 113 static void thread_func(void *userdata) {
 114     struct userdata *u = userdata;
 115     struct pollfd pollfd;
 116
 117     pa_assert(u);
 118
 119     pa_log_debug("Thread starting up");
 120
 121     pa_gettimeofday(&u->timestamp);
 122
 123     memset(&pollfd, 0, sizeof(pollfd));
 124     pollfd.fd = pa_asyncmsgq_get_fd(u->asyncmsgq);
 125     pollfd.events = POLLIN;
 126
 127     for (;;) {
 128         pa_msgobject *object;
 129         int code;
 130         void *data;
 131         pa_memchunk chunk;
 132         int r, timeout;
 133         struct timeval now;
 134
 135         /* Check whether there is a message for us to process */
 136         if (pa_asyncmsgq_get(u->asyncmsgq, &object, &code, &data, &chunk, 0) == 0) {
 137             int ret;
 138
 139             if (!object && code == PA_MESSAGE_SHUTDOWN) {
 140                 pa_asyncmsgq_done(u->asyncmsgq, 0);
 141                 goto finish;
 142             }
 143
 144             ret = pa_asyncmsgq_dispatch(object, code, data, &chunk);
 145             pa_asyncmsgq_done(u->asyncmsgq, ret);
 146             continue;
 147         }
 148
 149         /* Render some data and drop it immediately */
 150         if (u->sink->thread_info.state == PA_SINK_RUNNING) {
 151             pa_gettimeofday(&now);
 152
 153             if (pa_timeval_cmp(&u->timestamp, &now) <= 0) {
 154                 size_t l;
 155
 156                 if (pa_sink_render(u->sink, u->block_size, &chunk) >= 0) {
 157                     l = chunk.length;
 158                     pa_memblock_unref(chunk.memblock);
 159                 } else
 160                     l = u->block_size;
 161
 162                 pa_timeval_add(&u->timestamp, pa_bytes_to_usec(l, &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->asyncmsgq) < 0)
 176             continue;
 177
 178         r = poll(&pollfd, 1, timeout);
 179         pa_asyncmsgq_after_poll(u->asyncmsgq);
 180
 181         if (r < 0) {
 182             if (errno == EINTR)
 183                 continue;
 184
 185             pa_log("poll() failed: %s", pa_cstrerror(errno));
 186             goto fail;
 187         }
 188
 189         pa_assert(r == 0 || pollfd.revents == POLLIN);
 190     }
 191
 192 fail:
 193     /* We have to continue processing messages until we receive the
 194      * SHUTDOWN message */
 195     pa_asyncmsgq_post(u->core->asyncmsgq, PA_MSGOBJECT(u->core), PA_CORE_MESSAGE_UNLOAD_MODULE, u->module, NULL, NULL);
 196     pa_asyncmsgq_wait_for(u->asyncmsgq, PA_MESSAGE_SHUTDOWN);
 197
 198 finish:
 199     pa_log_debug("Thread shutting down");
 200 }
 201
 202 int pa__init(pa_core *c, pa_module*m) {
 203     struct userdata *u = NULL;
 204     pa_sample_spec ss;
 205     pa_channel_map map;
 206     pa_modargs *ma = NULL;
 207
 208     pa_assert(c);
 209     pa_assert(m);
 210
 211     if (!(ma = pa_modargs_new(m->argument, valid_modargs))) {
 212         pa_log("Failed to parse module arguments.");
 213         goto fail;
 214     }
 215
 216     ss = c->default_sample_spec;
 217     if (pa_modargs_get_sample_spec_and_channel_map(ma, &ss, &map, PA_CHANNEL_MAP_DEFAULT) < 0) {
 218         pa_log("Invalid sample format specification or channel map");
 219         goto fail;
 220     }
 221
 222     u = pa_xnew0(struct userdata, 1);
 223     u->core = c;
 224     u->module = m;
 225     m->userdata = u;
 226
 227     pa_assert_se(u->asyncmsgq = pa_asyncmsgq_new(0));
 228
 229     if (!(u->sink = pa_sink_new(c, __FILE__, pa_modargs_get_value(ma, "sink_name", DEFAULT_SINK_NAME), 0, &ss, &map))) {
 230         pa_log("Failed to create sink.");
 231         goto fail;
 232     }
 233
 234     u->sink->parent.process_msg = sink_process_msg;
 235     u->sink->userdata = u;
 236
 237     pa_sink_set_module(u->sink, m);
 238     pa_sink_set_asyncmsgq(u->sink, u->asyncmsgq);
 239     pa_sink_set_description(u->sink, pa_modargs_get_value(ma, "description", "NULL sink"));
 240
 241     u->block_size = pa_bytes_per_second(&ss) / 20; /* 50 ms */
 242     if (u->block_size <= 0)
 243         u->block_size = pa_frame_size(&ss);
 244
 245     if (!(u->thread = pa_thread_new(thread_func, u))) {
 246         pa_log("Failed to create thread.");
 247         goto fail;
 248     }
 249
 250     pa_modargs_free(ma);
 251
 252     return 0;
 253
 254 fail:
 255     if (ma)
 256         pa_modargs_free(ma);
 257
 258     pa__done(c, m);
 259
 260     return -1;
 261 }
 262
 263 void pa__done(pa_core *c, pa_module*m) {
 264     struct userdata *u;
 265
 266     pa_assert(c);
 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->asyncmsgq, NULL, PA_MESSAGE_SHUTDOWN, NULL, NULL);
 277         pa_thread_free(u->thread);
 278     }
 279
 280     if (u->asyncmsgq)
 281         pa_asyncmsgq_free(u->asyncmsgq);
 282
 283     if (u->sink)
 284         pa_sink_unref(u->sink);
 285
 286     pa_xfree(u);
 287 }