1 /***
2 This file is part of PulseAudio.
3
4 Copyright 2008 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 <stdlib.h>
25 #include <stdio.h>
26 #include <errno.h>
27 #include <unistd.h>
28
29 #include <pulse/rtclock.h>
30 #include <pulse/timeval.h>
31 #include <pulse/xmalloc.h>
32
33 #include <pulsecore/source.h>
34 #include <pulsecore/module.h>
35 #include <pulsecore/core-util.h>
36 #include <pulsecore/modargs.h>
37 #include <pulsecore/log.h>
38 #include <pulsecore/thread.h>
39 #include <pulsecore/thread-mq.h>
40 #include <pulsecore/rtpoll.h>
41
42 PA_MODULE_AUTHOR("Lennart Poettering");
43 PA_MODULE_DESCRIPTION("Sine wave generator source");
44 PA_MODULE_VERSION(PACKAGE_VERSION);
45 PA_MODULE_LOAD_ONCE(false);
46 PA_MODULE_USAGE(
47 "source_name=<name for the source> "
48 "source_properties=<properties for the source> "
49 "rate=<sample rate> "
50 "frequency=<frequency in Hz>");
51
52 #define DEFAULT_SOURCE_NAME "sine_input"
53 #define BLOCK_USEC (PA_USEC_PER_SEC * 2)
54
55 struct userdata {
56 pa_core *core;
57 pa_module *module;
58 pa_source *source;
59
60 pa_thread *thread;
61 pa_thread_mq thread_mq;
62 pa_rtpoll *rtpoll;
63
64 pa_memchunk memchunk;
65 size_t peek_index;
66
67 pa_usec_t block_usec; /* how much to push at once */
68 pa_usec_t timestamp; /* when to push next */
69 };
70
71 static const char* const valid_modargs[] = {
72 "source_name",
73 "source_properties",
74 "rate",
75 "frequency",
76 NULL
77 };
78
source_process_msg( pa_msgobject *o, int code, void *data, int64_t offset, pa_memchunk *chunk)79 static int source_process_msg(
80 pa_msgobject *o,
81 int code,
82 void *data,
83 int64_t offset,
84 pa_memchunk *chunk) {
85
86 struct userdata *u = PA_SOURCE(o)->userdata;
87
88 switch (code) {
89
90 case PA_SOURCE_MESSAGE_GET_LATENCY: {
91 pa_usec_t now, left_to_fill;
92
93 now = pa_rtclock_now();
94 left_to_fill = u->timestamp > now ? u->timestamp - now : 0ULL;
95
96 *((int64_t*) data) = (int64_t)u->block_usec - left_to_fill;
97
98 return 0;
99 }
100 }
101
102 return pa_source_process_msg(o, code, data, offset, chunk);
103 }
104
105 /* Called from the IO thread. */
source_set_state_in_io_thread_cb(pa_source *s, pa_source_state_t new_state, pa_suspend_cause_t new_suspend_cause)106 static int source_set_state_in_io_thread_cb(pa_source *s, pa_source_state_t new_state, pa_suspend_cause_t new_suspend_cause) {
107 struct userdata *u;
108
109 pa_assert(s);
110 pa_assert_se(u = s->userdata);
111
112 if (new_state == PA_SOURCE_RUNNING)
113 u->timestamp = pa_rtclock_now();
114
115 return 0;
116 }
117
source_update_requested_latency_cb(pa_source *s)118 static void source_update_requested_latency_cb(pa_source *s) {
119 struct userdata *u;
120
121 pa_source_assert_ref(s);
122 pa_assert_se(u = s->userdata);
123
124 u->block_usec = pa_source_get_requested_latency_within_thread(s);
125
126 if (u->block_usec == (pa_usec_t) -1)
127 u->block_usec = s->thread_info.max_latency;
128
129 pa_log_debug("new block msec = %lu", (unsigned long) (u->block_usec / PA_USEC_PER_MSEC));
130 }
131
process_render(struct userdata *u, pa_usec_t now)132 static void process_render(struct userdata *u, pa_usec_t now) {
133 pa_assert(u);
134
135 while (u->timestamp < now + u->block_usec) {
136 pa_memchunk chunk;
137 size_t k;
138
139 k = pa_usec_to_bytes_round_up(now + u->block_usec - u->timestamp, &u->source->sample_spec);
140
141 chunk = u->memchunk;
142 chunk.index += u->peek_index;
143 chunk.length = PA_MIN(chunk.length - u->peek_index, k);
144
145 /* pa_log_debug("posting %lu", (unsigned long) chunk.length); */
146 pa_source_post(u->source, &chunk);
147
148 u->peek_index += chunk.length;
149 while (u->peek_index >= u->memchunk.length)
150 u->peek_index -= u->memchunk.length;
151
152 u->timestamp += pa_bytes_to_usec(chunk.length, &u->source->sample_spec);
153 }
154 }
155
thread_func(void *userdata)156 static void thread_func(void *userdata) {
157 struct userdata *u = userdata;
158
159 pa_assert(u);
160
161 pa_log_debug("Thread starting up");
162
163 pa_thread_mq_install(&u->thread_mq);
164
165 u->timestamp = pa_rtclock_now();
166
167 for (;;) {
168 int ret;
169
170 if (PA_SOURCE_IS_OPENED(u->source->thread_info.state)) {
171 pa_usec_t now;
172
173 now = pa_rtclock_now();
174
175 if (u->timestamp <= now)
176 process_render(u, now);
177
178 pa_rtpoll_set_timer_absolute(u->rtpoll, u->timestamp);
179 } else
180 pa_rtpoll_set_timer_disabled(u->rtpoll);
181
182 /* Hmm, nothing to do. Let's sleep */
183 if ((ret = pa_rtpoll_run(u->rtpoll)) < 0)
184 goto fail;
185
186 if (ret == 0)
187 goto finish;
188 }
189
190 fail:
191 /* If this was no regular exit from the loop we have to continue
192 * processing messages until we received PA_MESSAGE_SHUTDOWN */
193 pa_asyncmsgq_post(u->thread_mq.outq, PA_MSGOBJECT(u->core), PA_CORE_MESSAGE_UNLOAD_MODULE, u->module, 0, NULL, NULL);
194 pa_asyncmsgq_wait_for(u->thread_mq.inq, PA_MESSAGE_SHUTDOWN);
195
196 finish:
197 pa_log_debug("Thread shutting down");
198 }
199
pa__init(pa_module*m)200 int pa__init(pa_module*m) {
201 struct userdata *u;
202 pa_modargs *ma;
203 pa_source_new_data data;
204 uint32_t frequency;
205 pa_sample_spec ss;
206
207 pa_assert(m);
208
209 if (!(ma = pa_modargs_new(m->argument, valid_modargs))) {
210 pa_log("failed to parse module arguments.");
211 goto fail;
212 }
213
214 ss.format = PA_SAMPLE_FLOAT32;
215 ss.channels = 1;
216 ss.rate = 44100;
217
218 if (pa_modargs_get_sample_rate(ma, &ss.rate) < 0) {
219 pa_log("Invalid rate specification");
220 goto fail;
221 }
222
223 frequency = 440;
224 if (pa_modargs_get_value_u32(ma, "frequency", &frequency) < 0 || frequency < 1 || frequency > ss.rate/2) {
225 pa_log("Invalid frequency specification");
226 goto fail;
227 }
228
229 m->userdata = u = pa_xnew0(struct userdata, 1);
230 u->core = m->core;
231 u->module = m;
232 u->rtpoll = pa_rtpoll_new();
233
234 if (pa_thread_mq_init(&u->thread_mq, m->core->mainloop, u->rtpoll) < 0) {
235 pa_log("pa_thread_mq_init() failed.");
236 goto fail;
237 }
238
239 u->peek_index = 0;
240 pa_memchunk_sine(&u->memchunk, m->core->mempool, ss.rate, frequency);
241
242 pa_source_new_data_init(&data);
243 data.driver = __FILE__;
244 data.module = m;
245 pa_source_new_data_set_name(&data, pa_modargs_get_value(ma, "source_name", DEFAULT_SOURCE_NAME));
246 pa_proplist_setf(data.proplist, PA_PROP_DEVICE_DESCRIPTION, "Sine source at %u Hz", (unsigned) frequency);
247 pa_proplist_sets(data.proplist, PA_PROP_DEVICE_CLASS, "abstract");
248 pa_proplist_setf(data.proplist, "sine.hz", "%u", frequency);
249 pa_source_new_data_set_sample_spec(&data, &ss);
250
251 if (pa_modargs_get_proplist(ma, "source_properties", data.proplist, PA_UPDATE_REPLACE) < 0) {
252 pa_log("Invalid properties");
253 pa_source_new_data_done(&data);
254 goto fail;
255 }
256
257 u->source = pa_source_new(m->core, &data, PA_SOURCE_LATENCY);
258 pa_source_new_data_done(&data);
259
260 if (!u->source) {
261 pa_log("Failed to create source.");
262 goto fail;
263 }
264
265 u->source->parent.process_msg = source_process_msg;
266 u->source->set_state_in_io_thread = source_set_state_in_io_thread_cb;
267 u->source->update_requested_latency = source_update_requested_latency_cb;
268 u->source->userdata = u;
269
270 u->block_usec = BLOCK_USEC;
271
272 pa_source_set_asyncmsgq(u->source, u->thread_mq.inq);
273 pa_source_set_rtpoll(u->source, u->rtpoll);
274 pa_source_set_fixed_latency(u->source, u->block_usec);
275
276 if (!(u->thread = pa_thread_new("sine-source", thread_func, u))) {
277 pa_log("Failed to create thread.");
278 goto fail;
279 }
280
281 pa_source_put(u->source);
282
283 pa_modargs_free(ma);
284
285 return 0;
286
287 fail:
288 if (ma)
289 pa_modargs_free(ma);
290
291 pa__done(m);
292
293 return -1;
294 }
295
pa__get_n_used(pa_module *m)296 int pa__get_n_used(pa_module *m) {
297 struct userdata *u;
298
299 pa_assert(m);
300 pa_assert_se(u = m->userdata);
301
302 return pa_source_linked_by(u->source);
303 }
304
pa__done(pa_module*m)305 void pa__done(pa_module*m) {
306 struct userdata *u;
307
308 pa_assert(m);
309
310 if (!(u = m->userdata))
311 return;
312
313 if (u->source)
314 pa_source_unlink(u->source);
315
316 if (u->thread) {
317 pa_asyncmsgq_send(u->thread_mq.inq, NULL, PA_MESSAGE_SHUTDOWN, NULL, 0, NULL);
318 pa_thread_free(u->thread);
319 }
320
321 pa_thread_mq_done(&u->thread_mq);
322
323 if (u->source)
324 pa_source_unref(u->source);
325
326 if (u->memchunk.memblock)
327 pa_memblock_unref(u->memchunk.memblock);
328
329 if (u->rtpoll)
330 pa_rtpoll_free(u->rtpoll);
331
332 pa_xfree(u);
333 }
334