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