summaryrefslogtreecommitdiff
path: root/src/modules/module-null-sink.c
blob: d6ea43fd3bca5f3172889fa63fc533865201d687 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
/***
  This file is part of PulseAudio.

  Copyright 2004-2008 Lennart Poettering

  PulseAudio is free software; you can redistribute it and/or modify
  it under the terms of the GNU Lesser General Public License as published
  by the Free Software Foundation; either version 2.1 of the License,
  or (at your option) any later version.

  PulseAudio is distributed in the hope that it will be useful, but
  WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  General Public License for more details.

  You should have received a copy of the GNU Lesser General Public License
  along with PulseAudio; if not, write to the Free Software
  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  USA.
***/

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <unistd.h>

#include <pulse/rtclock.h>
#include <pulse/timeval.h>
#include <pulse/xmalloc.h>

#include <pulsecore/i18n.h>
#include <pulsecore/macro.h>
#include <pulsecore/sink.h>
#include <pulsecore/module.h>
#include <pulsecore/core-util.h>
#include <pulsecore/modargs.h>
#include <pulsecore/log.h>
#include <pulsecore/thread.h>
#include <pulsecore/thread-mq.h>
#include <pulsecore/rtpoll.h>

#include "module-null-sink-symdef.h"

PA_MODULE_AUTHOR("Lennart Poettering");
PA_MODULE_DESCRIPTION(_("Clocked NULL sink"));
PA_MODULE_VERSION(PACKAGE_VERSION);
PA_MODULE_LOAD_ONCE(FALSE);
PA_MODULE_USAGE(
        "sink_name=<name of sink> "
        "sink_properties=<properties for the sink> "
        "format=<sample format> "
        "rate=<sample rate> "
        "channels=<number of channels> "
        "channel_map=<channel map>");

#define DEFAULT_SINK_NAME "null"
#define BLOCK_USEC (PA_USEC_PER_SEC * 2)

struct userdata {
    pa_core *core;
    pa_module *module;
    pa_sink *sink;

    pa_thread *thread;
    pa_thread_mq thread_mq;
    pa_rtpoll *rtpoll;

    pa_usec_t block_usec;
    pa_usec_t timestamp;
};

static const char* const valid_modargs[] = {
    "sink_name",
    "sink_properties",
    "format",
    "rate",
    "channels",
    "channel_map",
    NULL
};

static int sink_process_msg(
        pa_msgobject *o,
        int code,
        void *data,
        int64_t offset,
        pa_memchunk *chunk) {

    struct userdata *u = PA_SINK(o)->userdata;

    switch (code) {
        case PA_SINK_MESSAGE_SET_STATE:

            if (PA_PTR_TO_UINT(data) == PA_SINK_RUNNING)
                u->timestamp = pa_rtclock_now();

            break;

        case PA_SINK_MESSAGE_GET_LATENCY: {
            pa_usec_t now;

            now = pa_rtclock_now();
            *((pa_usec_t*) data) = u->timestamp > now ? u->timestamp - now : 0ULL;

            return 0;
        }
    }

    return pa_sink_process_msg(o, code, data, offset, chunk);
}

static void sink_update_requested_latency_cb(pa_sink *s) {
    struct userdata *u;
    size_t nbytes;

    pa_sink_assert_ref(s);
    pa_assert_se(u = s->userdata);

    u->block_usec = pa_sink_get_requested_latency_within_thread(s);

    if (u->block_usec == (pa_usec_t) -1)
        u->block_usec = s->thread_info.max_latency;

    nbytes = pa_usec_to_bytes(u->block_usec, &s->sample_spec);
    pa_sink_set_max_rewind_within_thread(s, nbytes);
    pa_sink_set_max_request_within_thread(s, nbytes);
}

static void process_rewind(struct userdata *u, pa_usec_t now) {
    size_t rewind_nbytes, in_buffer;
    pa_usec_t delay;

    pa_assert(u);

    rewind_nbytes = u->sink->thread_info.rewind_nbytes;

    if (!PA_SINK_IS_OPENED(u->sink->thread_info.state) || rewind_nbytes <= 0)
        goto do_nothing;

    pa_log_debug("Requested to rewind %lu bytes.", (unsigned long) rewind_nbytes);

    if (u->timestamp <= now)
        goto do_nothing;

    delay = u->timestamp - now;
    in_buffer = pa_usec_to_bytes(delay, &u->sink->sample_spec);

    if (in_buffer <= 0)
        goto do_nothing;

    if (rewind_nbytes > in_buffer)
        rewind_nbytes = in_buffer;

    pa_sink_process_rewind(u->sink, rewind_nbytes);
    u->timestamp -= pa_bytes_to_usec(rewind_nbytes, &u->sink->sample_spec);

    pa_log_debug("Rewound %lu bytes.", (unsigned long) rewind_nbytes);
    return;

do_nothing:

    pa_sink_process_rewind(u->sink, 0);
}

static void process_render(struct userdata *u, pa_usec_t now) {
    size_t ate = 0;

    pa_assert(u);

    /* This is the configured latency. Sink inputs connected to us
    might not have a single frame more than the maxrequest value
    queued. Hence: at maximum read this many bytes from the sink
    inputs. */

    /* Fill the buffer up the latency size */
    while (u->timestamp < now + u->block_usec) {
        pa_memchunk chunk;

        pa_sink_render(u->sink, u->sink->thread_info.max_request, &chunk);
        pa_memblock_unref(chunk.memblock);

/*         pa_log_debug("Ate %lu bytes.", (unsigned long) chunk.length); */
        u->timestamp += pa_bytes_to_usec(chunk.length, &u->sink->sample_spec);

        ate += chunk.length;

        if (ate >= u->sink->thread_info.max_request)
            break;
    }

/*     pa_log_debug("Ate in sum %lu bytes (of %lu)", (unsigned long) ate, (unsigned long) nbytes); */
}

static void thread_func(void *userdata) {
    struct userdata *u = userdata;

    pa_assert(u);

    pa_log_debug("Thread starting up");

    pa_thread_mq_install(&u->thread_mq);

    u->timestamp = pa_rtclock_now();

    for (;;) {
        pa_usec_t now = 0;
        int ret;

        if (PA_SINK_IS_OPENED(u->sink->thread_info.state))
            now = pa_rtclock_now();

        if (u->sink->thread_info.rewind_requested)
            process_rewind(u, now);

        /* Render some data and drop it immediately */
        if (PA_SINK_IS_OPENED(u->sink->thread_info.state)) {
            if (u->timestamp <= now)
                process_render(u, now);

            pa_rtpoll_set_timer_absolute(u->rtpoll, u->timestamp);
        } else
            pa_rtpoll_set_timer_disabled(u->rtpoll);

        /* Hmm, nothing to do. Let's sleep */
        if ((ret = pa_rtpoll_run(u->rtpoll, TRUE)) < 0)
            goto fail;

        if (ret == 0)
            goto finish;
    }

fail:
    /* If this was no regular exit from the loop we have to continue
     * processing messages until we received PA_MESSAGE_SHUTDOWN */
    pa_asyncmsgq_post(u->thread_mq.outq, PA_MSGOBJECT(u->core), PA_CORE_MESSAGE_UNLOAD_MODULE, u->module, 0, NULL, NULL);
    pa_asyncmsgq_wait_for(u->thread_mq.inq, PA_MESSAGE_SHUTDOWN);

finish:
    pa_log_debug("Thread shutting down");
}

int pa__init(pa_module*m) {
    struct userdata *u = NULL;
    pa_sample_spec ss;
    pa_channel_map map;
    pa_modargs *ma = NULL;
    pa_sink_new_data data;
    size_t nbytes;

    pa_assert(m);

    if (!(ma = pa_modargs_new(m->argument, valid_modargs))) {
        pa_log("Failed to parse module arguments.");
        goto fail;
    }

    ss = m->core->default_sample_spec;
    map = m->core->default_channel_map;
    if (pa_modargs_get_sample_spec_and_channel_map(ma, &ss, &map, PA_CHANNEL_MAP_DEFAULT) < 0) {
        pa_log("Invalid sample format specification or channel map");
        goto fail;
    }

    m->userdata = u = pa_xnew0(struct userdata, 1);
    u->core = m->core;
    u->module = m;
    u->rtpoll = pa_rtpoll_new();
    pa_thread_mq_init(&u->thread_mq, m->core->mainloop, u->rtpoll);

    pa_sink_new_data_init(&data);
    data.driver = __FILE__;
    data.module = m;
    pa_sink_new_data_set_name(&data, pa_modargs_get_value(ma, "sink_name", DEFAULT_SINK_NAME));
    pa_sink_new_data_set_sample_spec(&data, &ss);
    pa_sink_new_data_set_channel_map(&data, &map);
    pa_proplist_sets(data.proplist, PA_PROP_DEVICE_DESCRIPTION, _("Null Output"));
    pa_proplist_sets(data.proplist, PA_PROP_DEVICE_CLASS, "abstract");

    if (pa_modargs_get_proplist(ma, "sink_properties", data.proplist, PA_UPDATE_REPLACE) < 0) {
        pa_log("Invalid properties");
        pa_sink_new_data_done(&data);
        goto fail;
    }

    u->sink = pa_sink_new(m->core, &data, PA_SINK_LATENCY|PA_SINK_DYNAMIC_LATENCY);
    pa_sink_new_data_done(&data);

    if (!u->sink) {
        pa_log("Failed to create sink object.");
        goto fail;
    }

    u->sink->parent.process_msg = sink_process_msg;
    u->sink->update_requested_latency = sink_update_requested_latency_cb;
    u->sink->userdata = u;

    pa_sink_set_asyncmsgq(u->sink, u->thread_mq.inq);
    pa_sink_set_rtpoll(u->sink, u->rtpoll);

    u->block_usec = BLOCK_USEC;
    nbytes = pa_usec_to_bytes(u->block_usec, &u->sink->sample_spec);
    pa_sink_set_max_rewind(u->sink, nbytes);
    pa_sink_set_max_request(u->sink, nbytes);

    if (!(u->thread = pa_thread_new("null-sink", thread_func, u))) {
        pa_log("Failed to create thread.");
        goto fail;
    }

    pa_sink_set_latency_range(u->sink, 0, BLOCK_USEC);

    pa_sink_put(u->sink);

    pa_modargs_free(ma);

    return 0;

fail:
    if (ma)
        pa_modargs_free(ma);

    pa__done(m);

    return -1;
}

int pa__get_n_used(pa_module *m) {
    struct userdata *u;

    pa_assert(m);
    pa_assert_se(u = m->userdata);

    return pa_sink_linked_by(u->sink);
}

void pa__done(pa_module*m) {
    struct userdata *u;

    pa_assert(m);

    if (!(u = m->userdata))
        return;

    if (u->sink)
        pa_sink_unlink(u->sink);

    if (u->thread) {
        pa_asyncmsgq_send(u->thread_mq.inq, NULL, PA_MESSAGE_SHUTDOWN, NULL, 0, NULL);
        pa_thread_free(u->thread);
    }

    pa_thread_mq_done(&u->thread_mq);

    if (u->sink)
        pa_sink_unref(u->sink);

    if (u->rtpoll)
        pa_rtpoll_free(u->rtpoll);

    pa_xfree(u);
}