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