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
);