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