code.delx.au - pulseaudio/blob - src/modules/module-sine.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 <stdio.h>
  29 #include <assert.h>
  30 #include <math.h>
  31
  32 #include <pulse/xmalloc.h>
  33
  34 #include <pulsecore/sink-input.h>
  35 #include <pulsecore/module.h>
  36 #include <pulsecore/modargs.h>
  37 #include <pulsecore/namereg.h>
  38 #include <pulsecore/log.h>
  39 #include <pulsecore/core-util.h>
  40
  41 #include "module-sine-symdef.h"
  42
  43 PA_MODULE_AUTHOR("Lennart Poettering")
  44 PA_MODULE_DESCRIPTION("Sine wave generator")
  45 PA_MODULE_USAGE("sink=<sink to connect to> frequency=<frequency in Hz>")
  46 PA_MODULE_VERSION(PACKAGE_VERSION)
  47
  48 struct userdata {
  49     pa_core *core;
  50     pa_module *module;
  51     pa_sink_input *sink_input;
  52     pa_memblock *memblock;
  53     size_t peek_index;
  54 };
  55
  56 static const char* const valid_modargs[] = {
  57     "sink",
  58     "frequency",
  59     NULL,
  60 };
  61
  62 static int sink_input_peek_cb(pa_sink_input *i, pa_memchunk *chunk) {
  63     struct userdata *u;
  64
  65     pa_assert(i);
  66     u = i->userdata;
  67     pa_assert(u);
  68     pa_assert(chunk);
  69
  70     chunk->memblock = pa_memblock_ref(u->memblock);
  71     chunk->index = u->peek_index;
  72     chunk->length = pa_memblock_get_length(u->memblock) - u->peek_index;
  73
  74     return 0;
  75 }
  76
  77 static void sink_input_drop_cb(pa_sink_input *i, size_t length) {
  78     struct userdata *u;
  79     size_t l;
  80
  81     pa_assert(i);
  82     u = i->userdata;
  83     pa_assert(u);
  84     pa_assert(length > 0);
  85
  86     u->peek_index += length;
  87
  88     l = pa_memblock_get_length(u->memblock);
  89
  90     while (u->peek_index >= l)
  91         u->peek_index -= l;
  92 }
  93
  94 static void sink_input_kill_cb(pa_sink_input *i) {
  95     struct userdata *u;
  96
  97     pa_assert(i);
  98     u = i->userdata;
  99     pa_assert(u);
 100
 101     pa_sink_input_disconnect(u->sink_input);
 102     pa_sink_input_unref(u->sink_input);
 103     u->sink_input = NULL;
 104
 105     pa_module_unload_request(u->module);
 106 }
 107
 108 static void calc_sine(float *f, size_t l, float freq) {
 109     size_t i;
 110
 111     l /= sizeof(float);
 112
 113     for (i = 0; i < l; i++)
 114         f[i] = (float) sin((double) i/l*M_PI*2*freq)/2;
 115 }
 116
 117 int pa__init(pa_core *c, pa_module*m) {
 118     pa_modargs *ma = NULL;
 119     struct userdata *u;
 120     pa_sink *sink;
 121     pa_sample_spec ss;
 122     uint32_t frequency;
 123     char t[256];
 124     void *p;
 125     pa_sink_input_new_data data;
 126
 127     if (!(ma = pa_modargs_new(m->argument, valid_modargs))) {
 128         pa_log("Failed to parse module arguments");
 129         goto fail;
 130     }
 131
 132     m->userdata = u = pa_xnew0(struct userdata, 1);
 133     u->core = c;
 134     u->module = m;
 135     u->sink_input = NULL;
 136     u->memblock = NULL;
 137     u->peek_index = 0;
 138
 139     if (!(sink = pa_namereg_get(c, pa_modargs_get_value(ma, "sink", NULL), PA_NAMEREG_SINK, 1))) {
 140         pa_log("No such sink.");
 141         goto fail;
 142     }
 143
 144     ss.format = PA_SAMPLE_FLOAT32;
 145     ss.rate = sink->sample_spec.rate;
 146     ss.channels = 1;
 147
 148     frequency = 440;
 149     if (pa_modargs_get_value_u32(ma, "frequency", &frequency) < 0 || frequency < 1 || frequency > ss.rate/2) {
 150         pa_log("Invalid frequency specification");
 151         goto fail;
 152     }
 153
 154     u->memblock = pa_memblock_new(c->mempool, pa_bytes_per_second(&ss));
 155     p = pa_memblock_acquire(u->memblock);
 156     calc_sine(p, pa_memblock_get_length(u->memblock), frequency);
 157     pa_memblock_release(u->memblock);
 158
 159     pa_snprintf(t, sizeof(t), "Sine Generator at %u Hz", frequency);
 160
 161     pa_sink_input_new_data_init(&data);
 162     data.sink = sink;
 163     data.driver = __FILE__;
 164     data.name = t;
 165     pa_sink_input_new_data_set_sample_spec(&data, &ss);
 166     data.module = m;
 167
 168     if (!(u->sink_input = pa_sink_input_new(c, &data, 0)))
 169         goto fail;
 170
 171     u->sink_input->peek = sink_input_peek_cb;
 172     u->sink_input->drop = sink_input_drop_cb;
 173     u->sink_input->kill = sink_input_kill_cb;
 174     u->sink_input->userdata = u;
 175
 176     pa_sink_input_put(u->sink_input);
 177
 178     pa_modargs_free(ma);
 179     return 0;
 180
 181 fail:
 182     if (ma)
 183         pa_modargs_free(ma);
 184
 185     pa__done(c, m);
 186     return -1;
 187 }
 188
 189 void pa__done(pa_core *c, pa_module*m) {
 190     struct userdata *u;
 191
 192     pa_assert(c);
 193     pa_assert(m);
 194
 195     if (!(u = m->userdata))
 196         return;
 197
 198     if (u->sink_input) {
 199         pa_sink_input_disconnect(u->sink_input);
 200         pa_sink_input_unref(u->sink_input);
 201     }
 202
 203     if (u->memblock)
 204         pa_memblock_unref(u->memblock);
 205
 206     pa_xfree(u);
 207 }
 208