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

   1 /* $Id$ */
   2
   3 /***
   4   This file is part of polypaudio.
   5
   6   polypaudio 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 of the License,
   9   or (at your option) any later version.
  10
  11   polypaudio 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 polypaudio; 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 <assert.h>
  30 #include <errno.h>
  31 #include <string.h>
  32 #include <fcntl.h>
  33 #include <unistd.h>
  34 #include <limits.h>
  35
  36 #include <polypcore/iochannel.h>
  37 #include <polypcore/sink.h>
  38 #include <polypcore/module.h>
  39 #include <polypcore/util.h>
  40 #include <polypcore/modargs.h>
  41 #include <polypcore/xmalloc.h>
  42 #include <polypcore/log.h>
  43
  44 #include "module-null-sink-symdef.h"
  45
  46 PA_MODULE_AUTHOR("Lennart Poettering")
  47 PA_MODULE_DESCRIPTION("Clocked NULL sink")
  48 PA_MODULE_VERSION(PACKAGE_VERSION)
  49 PA_MODULE_USAGE(
  50         "format=<sample format> "
  51         "channels=<number of channels> "
  52         "rate=<sample rate> "
  53         "sink_name=<name of sink>"
  54         "channel_map=<channel map>")
  55
  56 #define DEFAULT_SINK_NAME "null"
  57
  58 struct userdata {
  59     pa_core *core;
  60     pa_module *module;
  61     pa_sink *sink;
  62     pa_time_event *time_event;
  63     size_t block_size;
  64 };
  65
  66 static const char* const valid_modargs[] = {
  67     "rate",
  68     "format",
  69     "channels",
  70     "sink_name",
  71     "channel_map",
  72     NULL
  73 };
  74
  75 static void time_callback(pa_mainloop_api *m, pa_time_event*e, const struct timeval *tv, void *userdata) {
  76     struct userdata *u = userdata;
  77     pa_memchunk chunk;
  78     struct timeval ntv = *tv;
  79     size_t l;
  80
  81     assert(u);
  82
  83     if (pa_sink_render(u->sink, u->block_size, &chunk) >= 0) {
  84         l = chunk.length;
  85         pa_memblock_unref(chunk.memblock);
  86     } else
  87         l = u->block_size;
  88
  89     pa_timeval_add(&ntv, pa_bytes_to_usec(l, &u->sink->sample_spec));
  90     m->time_restart(e, &ntv);
  91 }
  92
  93 int pa__init(pa_core *c, pa_module*m) {
  94     struct userdata *u = NULL;
  95     pa_sample_spec ss;
  96     pa_channel_map map;
  97     pa_modargs *ma = NULL;
  98     struct timeval tv;
  99     assert(c && m);
 100
 101     if (!(ma = pa_modargs_new(m->argument, valid_modargs))) {
 102         pa_log(__FILE__": failed to parse module arguments.");
 103         goto fail;
 104     }
 105
 106     ss = c->default_sample_spec;
 107     if (pa_modargs_get_sample_spec_and_channel_map(ma, &ss, &map) < 0) {
 108         pa_log(__FILE__": invalid sample format specification or channel map.");
 109         goto fail;
 110     }
 111
 112     u = pa_xmalloc0(sizeof(struct userdata));
 113     u->core = c;
 114     u->module = m;
 115     m->userdata = u;
 116
 117     if (!(u->sink = pa_sink_new(c, __FILE__, pa_modargs_get_value(ma, "sink_name", DEFAULT_SINK_NAME), 0, &ss, &map))) {
 118         pa_log(__FILE__": failed to create sink.");
 119         goto fail;
 120     }
 121
 122     u->sink->userdata = u;
 123     pa_sink_set_owner(u->sink, m);
 124     u->sink->description = pa_sprintf_malloc("NULL sink");
 125
 126     pa_gettimeofday(&tv);
 127     u->time_event = c->mainloop->time_new(c->mainloop, &tv, time_callback, u);
 128
 129     u->block_size = pa_bytes_per_second(&ss) / 10;
 130
 131     pa_modargs_free(ma);
 132
 133     return 0;
 134
 135 fail:
 136     if (ma)
 137         pa_modargs_free(ma);
 138
 139     pa__done(c, m);
 140
 141     return -1;
 142 }
 143
 144 void pa__done(pa_core *c, pa_module*m) {
 145     struct userdata *u;
 146     assert(c && m);
 147
 148     if (!(u = m->userdata))
 149         return;
 150
 151     pa_sink_disconnect(u->sink);
 152     pa_sink_unref(u->sink);
 153
 154     u->core->mainloop->time_free(u->time_event);
 155
 156     pa_xfree(u);
 157 }