4 This file is part of PulseAudio.
6 Copyright 2004-2008 Lennart Poettering
8 PulseAudio is free software; you can redistribute it and/or modify
9 it under the terms of the GNU Lesser General Public License as published
10 by the Free Software Foundation; either version 2 of the License,
11 or (at your option) any later version.
13 PulseAudio is distributed in the hope that it will be useful, but
14 WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 General Public License for more details.
18 You should have received a copy of the GNU Lesser General Public License
19 along with PulseAudio; if not, write to the Free Software
20 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
37 #include <pulse/timeval.h>
38 #include <pulse/xmalloc.h>
40 #include <pulsecore/macro.h>
41 #include <pulsecore/sink.h>
42 #include <pulsecore/module.h>
43 #include <pulsecore/core-util.h>
44 #include <pulsecore/core-error.h>
45 #include <pulsecore/modargs.h>
46 #include <pulsecore/log.h>
47 #include <pulsecore/thread.h>
48 #include <pulsecore/thread-mq.h>
49 #include <pulsecore/rtpoll.h>
50 #include <pulsecore/rtclock.h>
52 #include "module-null-sink-symdef.h"
54 PA_MODULE_AUTHOR("Lennart Poettering");
55 PA_MODULE_DESCRIPTION("Clocked NULL sink");
56 PA_MODULE_VERSION(PACKAGE_VERSION);
57 PA_MODULE_LOAD_ONCE(FALSE);
59 "format=<sample format> "
60 "channels=<number of channels> "
62 "sink_name=<name of sink>"
63 "channel_map=<channel map>"
64 "description=<description for the sink>");
66 #define DEFAULT_SINK_NAME "null"
67 #define MAX_LATENCY_USEC (PA_USEC_PER_SEC * 2)
75 pa_thread_mq thread_mq;
84 static const char* const valid_modargs[] = {
94 static int sink_process_msg(pa_msgobject *o, int code, void *data, int64_t offset, pa_memchunk *chunk) {
95 struct userdata *u = PA_SINK(o)->userdata;
98 case PA_SINK_MESSAGE_SET_STATE:
100 if (PA_PTR_TO_UINT(data) == PA_SINK_RUNNING)
101 u->timestamp = pa_rtclock_usec();
105 case PA_SINK_MESSAGE_GET_LATENCY: {
108 now = pa_rtclock_usec();
109 *((pa_usec_t*) data) = u->timestamp > now ? u->timestamp - now : 0;
115 return pa_sink_process_msg(o, code, data, offset, chunk);
118 static void sink_update_requested_latency_cb(pa_sink *s) {
121 pa_sink_assert_ref(s);
125 u->block_usec = pa_sink_get_requested_latency_within_thread(s);
128 static void process_rewind(struct userdata *u, pa_usec_t now) {
129 size_t rewind_nbytes, in_buffer;
134 /* Figure out how much we shall rewind and reset the counter */
135 rewind_nbytes = u->sink->thread_info.rewind_nbytes;
136 u->sink->thread_info.rewind_nbytes = 0;
138 pa_assert(rewind_nbytes > 0);
139 pa_log_debug("Requested to rewind %lu bytes.", (unsigned long) rewind_nbytes);
141 if (u->timestamp <= now)
144 delay = u->timestamp - now;
145 in_buffer = pa_usec_to_bytes(delay, &u->sink->sample_spec);
150 if (rewind_nbytes > in_buffer)
151 rewind_nbytes = in_buffer;
153 pa_sink_process_rewind(u->sink, rewind_nbytes);
154 u->timestamp -= pa_bytes_to_usec(rewind_nbytes, &u->sink->sample_spec);
156 pa_log_debug("Rewound %lu bytes.", (unsigned long) rewind_nbytes);
159 static void process_render(struct userdata *u, pa_usec_t now) {
165 /* This is the configured latency. Sink inputs connected to us
166 might not have a single frame more than this value queued. Hence:
167 at maximum read this many bytes from the sink inputs. */
169 nbytes = pa_usec_to_bytes(u->block_usec, &u->sink->sample_spec);
171 /* Fill the buffer up the the latency size */
172 while (u->timestamp < now + u->block_usec) {
175 pa_sink_render(u->sink, nbytes, &chunk);
176 pa_memblock_unref(chunk.memblock);
178 pa_log_debug("Ate %lu bytes.", (unsigned long) chunk.length);
179 u->timestamp += pa_bytes_to_usec(chunk.length, &u->sink->sample_spec);
187 pa_log_debug("Ate in sum %lu bytes (of %lu)", (unsigned long) ate, (unsigned long) nbytes);
190 static void thread_func(void *userdata) {
191 struct userdata *u = userdata;
195 pa_log_debug("Thread starting up");
197 pa_thread_mq_install(&u->thread_mq);
198 pa_rtpoll_install(u->rtpoll);
200 u->timestamp = pa_rtclock_usec();
205 /* Render some data and drop it immediately */
206 if (u->sink->thread_info.state == PA_SINK_RUNNING) {
209 now = pa_rtclock_usec();
211 if (u->sink->thread_info.rewind_nbytes > 0)
212 process_rewind(u, now);
214 if (u->timestamp <= now)
215 process_render(u, now);
217 pa_rtpoll_set_timer_absolute(u->rtpoll, u->timestamp);
219 pa_rtpoll_set_timer_disabled(u->rtpoll);
221 /* Hmm, nothing to do. Let's sleep */
222 if ((ret = pa_rtpoll_run(u->rtpoll, TRUE)) < 0)
230 /* If this was no regular exit from the loop we have to continue
231 * processing messages until we received PA_MESSAGE_SHUTDOWN */
232 pa_asyncmsgq_post(u->thread_mq.outq, PA_MSGOBJECT(u->core), PA_CORE_MESSAGE_UNLOAD_MODULE, u->module, 0, NULL, NULL);
233 pa_asyncmsgq_wait_for(u->thread_mq.inq, PA_MESSAGE_SHUTDOWN);
236 pa_log_debug("Thread shutting down");
239 int pa__init(pa_module*m) {
240 struct userdata *u = NULL;
243 pa_modargs *ma = NULL;
244 pa_sink_new_data data;
248 if (!(ma = pa_modargs_new(m->argument, valid_modargs))) {
249 pa_log("Failed to parse module arguments.");
253 ss = m->core->default_sample_spec;
254 if (pa_modargs_get_sample_spec_and_channel_map(ma, &ss, &map, PA_CHANNEL_MAP_DEFAULT) < 0) {
255 pa_log("Invalid sample format specification or channel map");
259 u = pa_xnew0(struct userdata, 1);
263 u->rtpoll = pa_rtpoll_new();
264 pa_thread_mq_init(&u->thread_mq, m->core->mainloop, u->rtpoll);
266 pa_sink_new_data_init(&data);
267 data.driver = __FILE__;
269 pa_sink_new_data_set_name(&data, pa_modargs_get_value(ma, "sink_name", DEFAULT_SINK_NAME));
270 pa_sink_new_data_set_sample_spec(&data, &ss);
271 pa_sink_new_data_set_channel_map(&data, &map);
272 pa_proplist_sets(data.proplist, PA_PROP_DEVICE_DESCRIPTION, pa_modargs_get_value(ma, "description", "Null Output"));
274 u->sink = pa_sink_new(m->core, &data, PA_SINK_LATENCY);
275 pa_sink_new_data_done(&data);
278 pa_log("Failed to create sink object.");
282 u->sink->parent.process_msg = sink_process_msg;
283 u->sink->update_requested_latency = sink_update_requested_latency_cb;
284 u->sink->userdata = u;
286 pa_sink_set_asyncmsgq(u->sink, u->thread_mq.inq);
287 pa_sink_set_rtpoll(u->sink, u->rtpoll);
289 u->block_usec = u->sink->max_latency = MAX_LATENCY_USEC;
291 u->sink->thread_info.max_rewind = pa_usec_to_bytes(u->block_usec, &u->sink->sample_spec);
293 if (!(u->thread = pa_thread_new(thread_func, u))) {
294 pa_log("Failed to create thread.");
298 pa_sink_put(u->sink);
313 void pa__done(pa_module*m) {
318 if (!(u = m->userdata))
322 pa_sink_unlink(u->sink);
325 pa_asyncmsgq_send(u->thread_mq.inq, NULL, PA_MESSAGE_SHUTDOWN, NULL, 0, NULL);
326 pa_thread_free(u->thread);
329 pa_thread_mq_done(&u->thread_mq);
332 pa_sink_unref(u->sink);
335 pa_rtpoll_free(u->rtpoll);