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 2.1 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(
  45         "sink=<sink to connect to> "
  46         "frequency=<frequency in Hz>");
  47
  48 struct userdata {
  49     pa_core *core;
  50     pa_module *module;
  51     pa_sink_input *sink_input;
  52     pa_memchunk memchunk;
  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_pop_cb(pa_sink_input *i, size_t nbytes, pa_memchunk *chunk) {
  63     struct userdata *u;
  64
  65     pa_sink_input_assert_ref(i);
  66     pa_assert_se(u = i->userdata);
  67     pa_assert(chunk);
  68
  69     *chunk = u->memchunk;
  70     pa_memblock_ref(chunk->memblock);
  71
  72     chunk->index += u->peek_index;
  73     chunk->length -= u->peek_index;
  74
  75     u->peek_index = 0;
  76
  77     return 0;
  78 }
  79
  80 static void sink_input_process_rewind_cb(pa_sink_input *i, size_t nbytes) {
  81     struct userdata *u;
  82
  83     pa_sink_input_assert_ref(i);
  84     pa_assert_se(u = i->userdata);
  85
  86     nbytes %= u->memchunk.length;
  87
  88     if (u->peek_index >= nbytes)
  89         u->peek_index -= nbytes;
  90     else
  91         u->peek_index = u->memchunk.length + u->peek_index - nbytes;
  92 }
  93
  94 static void sink_input_kill_cb(pa_sink_input *i) {
  95     struct userdata *u;
  96
  97     pa_sink_input_assert_ref(i);
  98     pa_assert_se(u = i->userdata);
  99
 100     pa_sink_input_unlink(u->sink_input);
 101     pa_sink_input_unref(u->sink_input);
 102     u->sink_input = NULL;
 103
 104     pa_module_unload_request(u->module, TRUE);
 105 }
 106
 107 /* Called from IO thread context */
 108 static void sink_input_state_change_cb(pa_sink_input *i, pa_sink_input_state_t state) {
 109     struct userdata *u;
 110
 111     pa_sink_input_assert_ref(i);
 112     pa_assert_se(u = i->userdata);
 113
 114     /* If we are added for the first time, ask for a rewinding so that
 115      * we are heard right-away. */
 116     if (PA_SINK_INPUT_IS_LINKED(state) &&
 117         i->thread_info.state == PA_SINK_INPUT_INIT)
 118         pa_sink_input_request_rewind(i, 0, FALSE, TRUE, TRUE);
 119 }
 120
 121 int pa__init(pa_module*m) {
 122     pa_modargs *ma = NULL;
 123     struct userdata *u;
 124     pa_sink *sink;
 125     pa_sample_spec ss;
 126     uint32_t frequency;
 127     pa_sink_input_new_data data;
 128
 129     if (!(ma = pa_modargs_new(m->argument, valid_modargs))) {
 130         pa_log("Failed to parse module arguments");
 131         goto fail;
 132     }
 133
 134     if (!(sink = pa_namereg_get(m->core, pa_modargs_get_value(ma, "sink", NULL), PA_NAMEREG_SINK))) {
 135         pa_log("No such sink.");
 136         goto fail;
 137     }
 138
 139     ss.format = PA_SAMPLE_FLOAT32;
 140     ss.rate = sink->sample_spec.rate;
 141     ss.channels = 1;
 142
 143     frequency = 440;
 144     if (pa_modargs_get_value_u32(ma, "frequency", &frequency) < 0 || frequency < 1 || frequency > ss.rate/2) {
 145         pa_log("Invalid frequency specification");
 146         goto fail;
 147     }
 148
 149     m->userdata = u = pa_xnew0(struct userdata, 1);
 150     u->core = m->core;
 151     u->module = m;
 152     u->sink_input = NULL;
 153
 154     u->peek_index = 0;
 155     pa_memchunk_sine(&u->memchunk, m->core->mempool, ss.rate, frequency);
 156
 157     pa_sink_input_new_data_init(&data);
 158     data.driver = __FILE__;
 159     data.module = m;
 160     data.sink = sink;
 161     pa_proplist_setf(data.proplist, PA_PROP_MEDIA_NAME, "%u Hz Sine", frequency);
 162     pa_proplist_sets(data.proplist, PA_PROP_MEDIA_ROLE, "abstract");
 163     pa_proplist_setf(data.proplist, "sine.hz", "%u", frequency);
 164     pa_sink_input_new_data_set_sample_spec(&data, &ss);
 165
 166     pa_sink_input_new(&u->sink_input, m->core, &data);
 167     pa_sink_input_new_data_done(&data);
 168
 169     if (!u->sink_input)
 170         goto fail;
 171
 172     u->sink_input->pop = sink_input_pop_cb;
 173     u->sink_input->process_rewind = sink_input_process_rewind_cb;
 174     u->sink_input->kill = sink_input_kill_cb;
 175     u->sink_input->state_change = sink_input_state_change_cb;
 176     u->sink_input->userdata = u;
 177
 178     pa_sink_input_put(u->sink_input);
 179
 180     pa_modargs_free(ma);
 181     return 0;
 182
 183 fail:
 184     if (ma)
 185         pa_modargs_free(ma);
 186
 187     pa__done(m);
 188     return -1;
 189 }
 190
 191 void pa__done(pa_module*m) {
 192     struct userdata *u;
 193
 194     pa_assert(m);
 195
 196     if (!(u = m->userdata))
 197         return;
 198
 199     if (u->sink_input) {
 200         pa_sink_input_unlink(u->sink_input);
 201         pa_sink_input_unref(u->sink_input);
 202     }
 203
 204     if (u->memchunk.memblock)
 205         pa_memblock_unref(u->memchunk.memblock);
 206
 207     pa_xfree(u);
 208 }