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 <assert.h>
  32 #include <errno.h>
  33 #include <string.h>
  34 #include <fcntl.h>
  35 #include <unistd.h>
  36 #include <limits.h>
  37
  38 #include <pulse/timeval.h>
  39 #include <pulse/xmalloc.h>
  40
  41 #include <pulsecore/iochannel.h>
  42 #include <pulsecore/sink.h>
  43 #include <pulsecore/module.h>
  44 #include <pulsecore/core-util.h>
  45 #include <pulsecore/modargs.h>
  46 #include <pulsecore/log.h>
  47
  48 #include "module-null-sink-symdef.h"
  49
  50 PA_MODULE_AUTHOR("Lennart Poettering")
  51 PA_MODULE_DESCRIPTION("Clocked NULL sink")
  52 PA_MODULE_VERSION(PACKAGE_VERSION)
  53 PA_MODULE_USAGE(
  54         "format=<sample format> "
  55         "channels=<number of channels> "
  56         "rate=<sample rate> "
  57         "sink_name=<name of sink>"
  58         "channel_map=<channel map>"
  59         "description=<description for the sink>")
  60
  61 #define DEFAULT_SINK_NAME "null"
  62
  63 struct userdata {
  64     pa_core *core;
  65     pa_module *module;
  66     pa_sink *sink;
  67     pa_time_event *time_event;
  68     size_t block_size;
  69
  70     uint64_t n_bytes;
  71     struct timeval start_time;
  72 };
  73
  74 static const char* const valid_modargs[] = {
  75     "rate",
  76     "format",
  77     "channels",
  78     "sink_name",
  79     "channel_map",
  80     "description",
  81     NULL
  82 };
  83
  84 static void time_callback(pa_mainloop_api *m, pa_time_event*e, const struct timeval *tv, void *userdata) {
  85     struct userdata *u = userdata;
  86     pa_memchunk chunk;
  87     struct timeval ntv = *tv;
  88     size_t l;
  89
  90     assert(u);
  91
  92     if (pa_sink_render(u->sink, u->block_size, &chunk) >= 0) {
  93         l = chunk.length;
  94         pa_memblock_unref(chunk.memblock);
  95     } else
  96         l = u->block_size;
  97
  98     pa_timeval_add(&ntv, pa_bytes_to_usec(l, &u->sink->sample_spec));
  99     m->time_restart(e, &ntv);
 100
 101     u->n_bytes += l;
 102 }
 103
 104 static pa_usec_t get_latency(pa_sink *s) {
 105     struct userdata *u = s->userdata;
 106     pa_usec_t a, b;
 107     struct timeval now;
 108
 109     a = pa_timeval_diff(pa_gettimeofday(&now), &u->start_time);
 110     b = pa_bytes_to_usec(u->n_bytes, &s->sample_spec);
 111
 112     return b > a ? b - a : 0;
 113 }
 114
 115 int pa__init(pa_core *c, pa_module*m) {
 116     struct userdata *u = NULL;
 117     pa_sample_spec ss;
 118     pa_channel_map map;
 119     pa_modargs *ma = NULL;
 120
 121     assert(c);
 122     assert(m);
 123
 124     if (!(ma = pa_modargs_new(m->argument, valid_modargs))) {
 125         pa_log("failed to parse module arguments.");
 126         goto fail;
 127     }
 128
 129     ss = c->default_sample_spec;
 130     if (pa_modargs_get_sample_spec_and_channel_map(ma, &ss, &map, PA_CHANNEL_MAP_DEFAULT) < 0) {
 131         pa_log("invalid sample format specification or channel map.");
 132         goto fail;
 133     }
 134
 135     u = pa_xnew0(struct userdata, 1);
 136     u->core = c;
 137     u->module = m;
 138     m->userdata = u;
 139
 140     if (!(u->sink = pa_sink_new(c, __FILE__, pa_modargs_get_value(ma, "sink_name", DEFAULT_SINK_NAME), 0, &ss, &map))) {
 141         pa_log("failed to create sink.");
 142         goto fail;
 143     }
 144
 145     u->sink->get_latency = get_latency;
 146     u->sink->userdata = u;
 147     pa_sink_set_owner(u->sink, m);
 148     pa_sink_set_description(u->sink, pa_modargs_get_value(ma, "description", "NULL sink"));
 149
 150     u->n_bytes = 0;
 151     pa_gettimeofday(&u->start_time);
 152
 153     u->time_event = c->mainloop->time_new(c->mainloop, &u->start_time, time_callback, u);
 154
 155     u->block_size = pa_bytes_per_second(&ss) / 10;
 156
 157     pa_modargs_free(ma);
 158
 159     return 0;
 160
 161 fail:
 162     if (ma)
 163         pa_modargs_free(ma);
 164
 165     pa__done(c, m);
 166
 167     return -1;
 168 }
 169
 170 void pa__done(pa_core *c, pa_module*m) {
 171     struct userdata *u;
 172     assert(c && m);
 173
 174     if (!(u = m->userdata))
 175         return;
 176
 177     pa_sink_disconnect(u->sink);
 178     pa_sink_unref(u->sink);
 179
 180     u->core->mainloop->time_free(u->time_event);
 181
 182     pa_xfree(u);
 183 }