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 <polyp/timeval.h>
  37 #include <polyp/xmalloc.h>
  38
  39 #include <polypcore/iochannel.h>
  40 #include <polypcore/sink.h>
  41 #include <polypcore/module.h>
  42 #include <polypcore/core-util.h>
  43 #include <polypcore/modargs.h>
  44 #include <polypcore/log.h>
  45
  46 #include "module-null-sink-symdef.h"
  47
  48 PA_MODULE_AUTHOR("Lennart Poettering")
  49 PA_MODULE_DESCRIPTION("Clocked NULL sink")
  50 PA_MODULE_VERSION(PACKAGE_VERSION)
  51 PA_MODULE_USAGE(
  52         "format=<sample format> "
  53         "channels=<number of channels> "
  54         "rate=<sample rate> "
  55         "sink_name=<name of sink>"
  56         "channel_map=<channel map>")
  57
  58 #define DEFAULT_SINK_NAME "null"
  59
  60 struct userdata {
  61     pa_core *core;
  62     pa_module *module;
  63     pa_sink *sink;
  64     pa_time_event *time_event;
  65     size_t block_size;
  66 };
  67
  68 static const char* const valid_modargs[] = {
  69     "rate",
  70     "format",
  71     "channels",
  72     "sink_name",
  73     "channel_map",
  74     NULL
  75 };
  76
  77 static void time_callback(pa_mainloop_api *m, pa_time_event*e, const struct timeval *tv, void *userdata) {
  78     struct userdata *u = userdata;
  79     pa_memchunk chunk;
  80     struct timeval ntv = *tv;
  81     size_t l;
  82
  83     assert(u);
  84
  85     if (pa_sink_render(u->sink, u->block_size, &chunk) >= 0) {
  86         l = chunk.length;
  87         pa_memblock_unref(chunk.memblock);
  88     } else
  89         l = u->block_size;
  90
  91     pa_timeval_add(&ntv, pa_bytes_to_usec(l, &u->sink->sample_spec));
  92     m->time_restart(e, &ntv);
  93 }
  94
  95 int pa__init(pa_core *c, pa_module*m) {
  96     struct userdata *u = NULL;
  97     pa_sample_spec ss;
  98     pa_channel_map map;
  99     pa_modargs *ma = NULL;
 100     struct timeval tv;
 101     assert(c && m);
 102
 103     if (!(ma = pa_modargs_new(m->argument, valid_modargs))) {
 104         pa_log(__FILE__": failed to parse module arguments.");
 105         goto fail;
 106     }
 107
 108     ss = c->default_sample_spec;
 109     if (pa_modargs_get_sample_spec_and_channel_map(ma, &ss, &map, PA_CHANNEL_MAP_DEFAULT) < 0) {
 110         pa_log(__FILE__": invalid sample format specification or channel map.");
 111         goto fail;
 112     }
 113
 114     u = pa_xmalloc0(sizeof(struct userdata));
 115     u->core = c;
 116     u->module = m;
 117     m->userdata = u;
 118
 119     if (!(u->sink = pa_sink_new(c, __FILE__, pa_modargs_get_value(ma, "sink_name", DEFAULT_SINK_NAME), 0, &ss, &map))) {
 120         pa_log(__FILE__": failed to create sink.");
 121         goto fail;
 122     }
 123
 124     u->sink->userdata = u;
 125     pa_sink_set_owner(u->sink, m);
 126     u->sink->description = pa_sprintf_malloc("NULL sink");
 127
 128     pa_gettimeofday(&tv);
 129     u->time_event = c->mainloop->time_new(c->mainloop, &tv, time_callback, u);
 130
 131     u->block_size = pa_bytes_per_second(&ss) / 10;
 132
 133     pa_modargs_free(ma);
 134
 135     return 0;
 136
 137 fail:
 138     if (ma)
 139         pa_modargs_free(ma);
 140
 141     pa__done(c, m);
 142
 143     return -1;
 144 }
 145
 146 void pa__done(pa_core *c, pa_module*m) {
 147     struct userdata *u;
 148     assert(c && m);
 149
 150     if (!(u = m->userdata))
 151         return;
 152
 153     pa_sink_disconnect(u->sink);
 154     pa_sink_unref(u->sink);
 155
 156     u->core->mainloop->time_free(u->time_event);
 157
 158     pa_xfree(u);
 159 }