code.delx.au - pulseaudio/blob - src/modules/module-sine.c

   1 /***
   2   This file is part of PulseAudio.
   3
   4   Copyright 2004-2006 Lennart Poettering
   5
   6   PulseAudio 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   PulseAudio 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 PulseAudio; 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 <stdio.h>
  27 #include <math.h>
  28
  29 #include <pulse/xmalloc.h>
  30
  31 #include <pulsecore/sink-input.h>
  32 #include <pulsecore/module.h>
  33 #include <pulsecore/modargs.h>
  34 #include <pulsecore/namereg.h>
  35 #include <pulsecore/log.h>
  36 #include <pulsecore/core-util.h>
  37
  38 #include "module-sine-symdef.h"
  39
  40 PA_MODULE_AUTHOR("Lennart Poettering");
  41 PA_MODULE_DESCRIPTION("Sine wave generator");
  42 PA_MODULE_VERSION(PACKAGE_VERSION);
  43 PA_MODULE_LOAD_ONCE(FALSE);
  44 PA_MODULE_USAGE("sink=<sink to connect to> frequency=<frequency in Hz>");
  45
  46 struct userdata {
  47     pa_core *core;
  48     pa_module *module;
  49     pa_sink_input *sink_input;
  50     pa_memblock *memblock;
  51     size_t peek_index;
  52 };
  53
  54 static const char* const valid_modargs[] = {
  55     "sink",
  56     "frequency",
  57     NULL,
  58 };
  59
  60 static int sink_input_pop_cb(pa_sink_input *i, size_t nbytes, pa_memchunk *chunk) {
  61     struct userdata *u;
  62
  63     pa_sink_input_assert_ref(i);
  64     pa_assert_se(u = i->userdata);
  65     pa_assert(chunk);
  66
  67     chunk->memblock = pa_memblock_ref(u->memblock);
  68     chunk->length = pa_memblock_get_length(u->memblock) - u->peek_index;
  69     chunk->index = u->peek_index;
  70
  71     u->peek_index = 0;
  72
  73     return 0;
  74 }
  75
  76 static void sink_input_process_rewind_cb(pa_sink_input *i, size_t nbytes) {
  77     size_t l;
  78     struct userdata *u;
  79
  80     pa_sink_input_assert_ref(i);
  81     pa_assert_se(u = i->userdata);
  82
  83     l = pa_memblock_get_length(u->memblock);
  84     nbytes %= l;
  85
  86     if (u->peek_index >= nbytes)
  87         u->peek_index -= nbytes;
  88     else
  89         u->peek_index = l + u->peek_index - nbytes;
  90 }
  91
  92 static void sink_input_kill_cb(pa_sink_input *i) {
  93     struct userdata *u;
  94
  95     pa_sink_input_assert_ref(i);
  96     pa_assert_se(u = i->userdata);
  97
  98     pa_sink_input_unlink(u->sink_input);
  99     pa_sink_input_unref(u->sink_input);
 100     u->sink_input = NULL;
 101
 102     pa_module_unload_request(u->module, TRUE);
 103 }
 104
 105 /* Called from IO thread context */
 106 static void sink_input_state_change_cb(pa_sink_input *i, pa_sink_input_state_t state) {
 107     struct userdata *u;
 108
 109     pa_sink_input_assert_ref(i);
 110     pa_assert_se(u = i->userdata);
 111
 112     /* If we are added for the first time, ask for a rewinding so that
 113      * we are heard right-away. */
 114     if (PA_SINK_INPUT_IS_LINKED(state) &&
 115         i->thread_info.state == PA_SINK_INPUT_INIT)
 116         pa_sink_input_request_rewind(i, 0, FALSE, TRUE);
 117 }
 118
 119 static void calc_sine(float *f, size_t l, float freq) {
 120     size_t i;
 121
 122     l /= sizeof(float);
 123
 124     for (i = 0; i < l; i++)
 125         f[i] = (float) sin((double) i/l*M_PI*2*freq)/2;
 126 }
 127
 128 int pa__init(pa_module*m) {
 129     pa_modargs *ma = NULL;
 130     struct userdata *u;
 131     pa_sink *sink;
 132     pa_sample_spec ss;
 133     uint32_t frequency;
 134     void *p;
 135     pa_sink_input_new_data data;
 136
 137     if (!(ma = pa_modargs_new(m->argument, valid_modargs))) {
 138         pa_log("Failed to parse module arguments");
 139         goto fail;
 140     }
 141
 142     m->userdata = u = pa_xnew0(struct userdata, 1);
 143     u->core = m->core;
 144     u->module = m;
 145     u->sink_input = NULL;
 146     u->memblock = NULL;
 147     u->peek_index = 0;
 148
 149     if (!(sink = pa_namereg_get(m->core, pa_modargs_get_value(ma, "sink", NULL), PA_NAMEREG_SINK, 1))) {
 150         pa_log("No such sink.");
 151         goto fail;
 152     }
 153
 154     ss.format = PA_SAMPLE_FLOAT32;
 155     ss.rate = sink->sample_spec.rate;
 156     ss.channels = 1;
 157
 158     frequency = 440;
 159     if (pa_modargs_get_value_u32(ma, "frequency", &frequency) < 0 || frequency < 1 || frequency > ss.rate/2) {
 160         pa_log("Invalid frequency specification");
 161         goto fail;
 162     }
 163
 164     u->memblock = pa_memblock_new(m->core->mempool, pa_bytes_per_second(&ss));
 165     p = pa_memblock_acquire(u->memblock);
 166     calc_sine(p, pa_memblock_get_length(u->memblock), frequency);
 167     pa_memblock_release(u->memblock);
 168
 169     pa_sink_input_new_data_init(&data);
 170     data.sink = sink;
 171     data.driver = __FILE__;
 172     pa_proplist_setf(data.proplist, PA_PROP_MEDIA_NAME, "%u Hz Sine", frequency);
 173     pa_proplist_sets(data.proplist, PA_PROP_MEDIA_ROLE, "abstract");
 174     pa_proplist_setf(data.proplist, "sine.hz", "%u", frequency);
 175     pa_sink_input_new_data_set_sample_spec(&data, &ss);
 176     data.module = m;
 177
 178     u->sink_input = pa_sink_input_new(m->core, &data, 0);
 179     pa_sink_input_new_data_done(&data);
 180
 181     if (!u->sink_input)
 182         goto fail;
 183
 184     u->sink_input->pop = sink_input_pop_cb;
 185     u->sink_input->process_rewind = sink_input_process_rewind_cb;
 186     u->sink_input->kill = sink_input_kill_cb;
 187     u->sink_input->state_change = sink_input_state_change_cb;
 188     u->sink_input->userdata = u;
 189
 190     pa_sink_input_put(u->sink_input);
 191
 192     pa_modargs_free(ma);
 193     return 0;
 194
 195 fail:
 196     if (ma)
 197         pa_modargs_free(ma);
 198
 199     pa__done(m);
 200     return -1;
 201 }
 202
 203 void pa__done(pa_module*m) {
 204     struct userdata *u;
 205
 206     pa_assert(m);
 207
 208     if (!(u = m->userdata))
 209         return;
 210
 211     if (u->sink_input) {
 212         pa_sink_input_unlink(u->sink_input);
 213         pa_sink_input_unref(u->sink_input);
 214     }
 215
 216     if (u->memblock)
 217         pa_memblock_unref(u->memblock);
 218
 219     pa_xfree(u);
 220 }