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/* $Id$ */
/***
This file is part of PulseAudio.
PulseAudio is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published
by the Free Software Foundation; either version 2 of the License,
or (at your option) any later version.
PulseAudio is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with PulseAudio; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
USA.
***/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <stdio.h>
#include <assert.h>
#include <math.h>
#include <pulse/xmalloc.h>
#include <pulsecore/sink-input.h>
#include <pulsecore/module.h>
#include <pulsecore/modargs.h>
#include <pulsecore/namereg.h>
#include <pulsecore/log.h>
#include "module-sine-symdef.h"
PA_MODULE_AUTHOR("Lennart Poettering")
PA_MODULE_DESCRIPTION("Sine wave generator")
PA_MODULE_USAGE("sink=<sink to connect to> frequency=<frequency in Hz>")
PA_MODULE_VERSION(PACKAGE_VERSION)
struct userdata {
pa_core *core;
pa_module *module;
pa_sink_input *sink_input;
pa_memblock *memblock;
size_t peek_index;
};
static const char* const valid_modargs[] = {
"sink",
"frequency",
NULL,
};
static int sink_input_peek(pa_sink_input *i, pa_memchunk *chunk) {
struct userdata *u;
assert(i && chunk && i->userdata);
u = i->userdata;
chunk->memblock = pa_memblock_ref(u->memblock);
chunk->index = u->peek_index;
chunk->length = u->memblock->length - u->peek_index;
return 0;
}
static void sink_input_drop(pa_sink_input *i, const pa_memchunk *chunk, size_t length) {
struct userdata *u;
assert(i && chunk && length && i->userdata);
u = i->userdata;
assert(chunk->memblock == u->memblock && length <= u->memblock->length-u->peek_index);
u->peek_index += length;
if (u->peek_index >= u->memblock->length)
u->peek_index = 0;
}
static void sink_input_kill(pa_sink_input *i) {
struct userdata *u;
assert(i && i->userdata);
u = i->userdata;
pa_sink_input_disconnect(u->sink_input);
pa_sink_input_unref(u->sink_input);
u->sink_input = NULL;
pa_module_unload_request(u->module);
}
static void calc_sine(float *f, size_t l, float freq) {
size_t i;
l /= sizeof(float);
for (i = 0; i < l; i++)
f[i] = (float) sin((double) i/l*M_PI*2*freq)/2;
}
int pa__init(pa_core *c, pa_module*m) {
pa_modargs *ma = NULL;
struct userdata *u;
pa_sink *sink;
const char *sink_name;
pa_sample_spec ss;
uint32_t frequency;
char t[256];
if (!(ma = pa_modargs_new(m->argument, valid_modargs))) {
pa_log(__FILE__": Failed to parse module arguments");
goto fail;
}
m->userdata = u = pa_xmalloc(sizeof(struct userdata));
u->core = c;
u->module = m;
u->sink_input = NULL;
u->memblock = NULL;
sink_name = pa_modargs_get_value(ma, "sink", NULL);
if (!(sink = pa_namereg_get(c, sink_name, PA_NAMEREG_SINK, 1))) {
pa_log(__FILE__": No such sink.");
goto fail;
}
ss.format = PA_SAMPLE_FLOAT32;
ss.rate = sink->sample_spec.rate;
ss.channels = 1;
frequency = 440;
if (pa_modargs_get_value_u32(ma, "frequency", &frequency) < 0 || frequency < 1 || frequency > ss.rate/2) {
pa_log(__FILE__": Invalid frequency specification");
goto fail;
}
u->memblock = pa_memblock_new(pa_bytes_per_second(&ss), c->memblock_stat);
calc_sine(u->memblock->data, u->memblock->length, frequency);
snprintf(t, sizeof(t), "Sine Generator at %u Hz", frequency);
if (!(u->sink_input = pa_sink_input_new(sink, __FILE__, t, &ss, NULL, NULL, 0, -1)))
goto fail;
u->sink_input->peek = sink_input_peek;
u->sink_input->drop = sink_input_drop;
u->sink_input->kill = sink_input_kill;
u->sink_input->userdata = u;
u->sink_input->owner = m;
u->peek_index = 0;
pa_modargs_free(ma);
return 0;
fail:
if (ma)
pa_modargs_free(ma);
pa__done(c, m);
return -1;
}
void pa__done(pa_core *c, pa_module*m) {
struct userdata *u = m->userdata;
assert(c && m);
if (!u)
return;
if (u->sink_input) {
pa_sink_input_disconnect(u->sink_input);
pa_sink_input_unref(u->sink_input);
}
if (u->memblock)
pa_memblock_unref(u->memblock);
pa_xfree(u);
}
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