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, see <http://www.gnu.org/licenses/>.
18***/
19
20#ifdef HAVE_CONFIG_H
21#include <config.h>
22#endif
23
24#include <stdio.h>
25
26#include <pulse/xmalloc.h>
27
28#include <pulsecore/sink-input.h>
29#include <pulsecore/module.h>
30#include <pulsecore/modargs.h>
31#include <pulsecore/namereg.h>
32#include <pulsecore/log.h>
33
34PA_MODULE_AUTHOR("Lennart Poettering");
35PA_MODULE_DESCRIPTION("Sine wave generator");
36PA_MODULE_VERSION(PACKAGE_VERSION);
37PA_MODULE_LOAD_ONCE(false);
38PA_MODULE_USAGE(
39        "sink=<sink to connect to> "
40        "rate=<sample rate> "
41        "frequency=<frequency in Hz>");
42
43struct userdata {
44    pa_core *core;
45    pa_module *module;
46    pa_sink_input *sink_input;
47    pa_memchunk memchunk;
48    size_t peek_index;
49};
50
51static const char* const valid_modargs[] = {
52    "sink",
53    "rate",
54    "frequency",
55    NULL,
56};
57
58static int sink_input_pop_cb(pa_sink_input *i, size_t nbytes, pa_memchunk *chunk) {
59    struct userdata *u;
60
61    pa_sink_input_assert_ref(i);
62    pa_assert_se(u = i->userdata);
63    pa_assert(chunk);
64
65    *chunk = u->memchunk;
66    pa_memblock_ref(chunk->memblock);
67
68    chunk->index += u->peek_index;
69    chunk->length -= u->peek_index;
70
71    u->peek_index = 0;
72
73    return 0;
74}
75
76static void sink_input_process_rewind_cb(pa_sink_input *i, size_t nbytes) {
77    struct userdata *u;
78
79    pa_sink_input_assert_ref(i);
80    pa_assert_se(u = i->userdata);
81
82    nbytes %= u->memchunk.length;
83
84    if (u->peek_index >= nbytes)
85        u->peek_index -= nbytes;
86    else
87        u->peek_index = u->memchunk.length + u->peek_index - nbytes;
88}
89
90static void sink_input_kill_cb(pa_sink_input *i) {
91    struct userdata *u;
92
93    pa_sink_input_assert_ref(i);
94    pa_assert_se(u = i->userdata);
95
96    pa_sink_input_unlink(u->sink_input);
97    pa_sink_input_unref(u->sink_input);
98    u->sink_input = NULL;
99
100    pa_module_unload_request(u->module, true);
101}
102
103/* Called from IO thread context */
104static void sink_input_state_change_cb(pa_sink_input *i, pa_sink_input_state_t state) {
105    struct userdata *u;
106
107    pa_sink_input_assert_ref(i);
108    pa_assert_se(u = i->userdata);
109
110    /* If we are added for the first time, ask for a rewinding so that
111     * we are heard right-away. */
112    if (PA_SINK_INPUT_IS_LINKED(state) &&
113        i->thread_info.state == PA_SINK_INPUT_INIT && i->sink)
114        pa_sink_input_request_rewind(i, 0, false, true, true);
115}
116
117int pa__init(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    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    if (!(sink = pa_namereg_get(m->core, pa_modargs_get_value(ma, "sink", NULL), PA_NAMEREG_SINK))) {
131        pa_log("No such sink.");
132        goto fail;
133    }
134
135    ss.format = PA_SAMPLE_FLOAT32;
136    ss.rate = sink->sample_spec.rate;
137    ss.channels = 1;
138
139    if (pa_modargs_get_sample_rate(ma, &ss.rate) < 0) {
140        pa_log("Invalid rate specification");
141        goto fail;
142    }
143
144    frequency = 440;
145    if (pa_modargs_get_value_u32(ma, "frequency", &frequency) < 0 || frequency < 1 || frequency > ss.rate/2) {
146        pa_log("Invalid frequency specification");
147        goto fail;
148    }
149
150    m->userdata = u = pa_xnew0(struct userdata, 1);
151    u->core = m->core;
152    u->module = m;
153    u->sink_input = NULL;
154
155    u->peek_index = 0;
156    pa_memchunk_sine(&u->memchunk, m->core->mempool, ss.rate, frequency);
157
158    pa_sink_input_new_data_init(&data);
159    data.driver = __FILE__;
160    data.module = m;
161    pa_sink_input_new_data_set_sink(&data, sink, false, true);
162    pa_proplist_setf(data.proplist, PA_PROP_MEDIA_NAME, "%u Hz Sine", frequency);
163    pa_proplist_sets(data.proplist, PA_PROP_MEDIA_ROLE, "abstract");
164    pa_proplist_setf(data.proplist, "sine.hz", "%u", frequency);
165    pa_sink_input_new_data_set_sample_spec(&data, &ss);
166
167    pa_sink_input_new(&u->sink_input, m->core, &data);
168    pa_sink_input_new_data_done(&data);
169
170    if (!u->sink_input)
171        goto fail;
172
173    u->sink_input->pop = sink_input_pop_cb;
174    u->sink_input->process_rewind = sink_input_process_rewind_cb;
175    u->sink_input->kill = sink_input_kill_cb;
176    u->sink_input->state_change = sink_input_state_change_cb;
177    u->sink_input->userdata = u;
178
179    pa_sink_input_put(u->sink_input);
180
181    pa_modargs_free(ma);
182    return 0;
183
184fail:
185    if (ma)
186        pa_modargs_free(ma);
187
188    pa__done(m);
189    return -1;
190}
191
192void pa__done(pa_module*m) {
193    struct userdata *u;
194
195    pa_assert(m);
196
197    if (!(u = m->userdata))
198        return;
199
200    if (u->sink_input) {
201        pa_sink_input_unlink(u->sink_input);
202        pa_sink_input_unref(u->sink_input);
203    }
204
205    if (u->memchunk.memblock)
206        pa_memblock_unref(u->memchunk.memblock);
207
208    pa_xfree(u);
209}
210