2 * Input async protocol.
3 * Copyright (c) 2015 Zhang Rui <bbcallen@gmail.com>
5 * This file is part of FFmpeg.
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 * Based on libavformat/cache.c by Michael Niedermayer
27 * support work with concatdec, hls
30 #include "libavutil/avassert.h"
31 #include "libavutil/avstring.h"
32 #include "libavutil/error.h"
33 #include "libavutil/fifo.h"
34 #include "libavutil/log.h"
35 #include "libavutil/opt.h"
36 #include "libavutil/thread.h"
44 #define BUFFER_CAPACITY (4 * 1024 * 1024)
45 #define READ_BACK_CAPACITY (4 * 1024 * 1024)
46 #define SHORT_SEEK_THRESHOLD (256 * 1024)
48 typedef struct RingBuffer
51 int read_back_capacity;
56 typedef struct Context {
74 pthread_cond_t cond_wakeup_main;
75 pthread_cond_t cond_wakeup_background;
76 pthread_mutex_t mutex;
77 pthread_t async_buffer_thread;
80 AVIOInterruptCB interrupt_callback;
83 static int ring_init(RingBuffer *ring, unsigned int capacity, int read_back_capacity)
85 memset(ring, 0, sizeof(RingBuffer));
86 ring->fifo = av_fifo_alloc(capacity + read_back_capacity);
88 return AVERROR(ENOMEM);
90 ring->read_back_capacity = read_back_capacity;
94 static void ring_destroy(RingBuffer *ring)
96 av_fifo_freep(&ring->fifo);
99 static void ring_reset(RingBuffer *ring)
101 av_fifo_reset(ring->fifo);
105 static int ring_size(RingBuffer *ring)
107 return av_fifo_size(ring->fifo) - ring->read_pos;
110 static int ring_space(RingBuffer *ring)
112 return av_fifo_space(ring->fifo);
115 static int ring_generic_read(RingBuffer *ring, void *dest, int buf_size, void (*func)(void*, void*, int))
119 av_assert2(buf_size <= ring_size(ring));
120 ret = av_fifo_generic_peek_at(ring->fifo, dest, ring->read_pos, buf_size, func);
121 ring->read_pos += buf_size;
123 if (ring->read_pos > ring->read_back_capacity) {
124 av_fifo_drain(ring->fifo, ring->read_pos - ring->read_back_capacity);
125 ring->read_pos = ring->read_back_capacity;
131 static int ring_generic_write(RingBuffer *ring, void *src, int size, int (*func)(void*, void*, int))
133 av_assert2(size <= ring_space(ring));
134 return av_fifo_generic_write(ring->fifo, src, size, func);
137 static int ring_size_of_read_back(RingBuffer *ring)
139 return ring->read_pos;
142 static int ring_drain(RingBuffer *ring, int offset)
144 av_assert2(offset >= -ring_size_of_read_back(ring));
145 av_assert2(offset <= -ring_size(ring));
146 ring->read_pos += offset;
150 static int async_check_interrupt(void *arg)
153 Context *c = h->priv_data;
155 if (c->abort_request)
158 if (ff_check_interrupt(&c->interrupt_callback))
159 c->abort_request = 1;
161 return c->abort_request;
164 static int wrapped_url_read(void *src, void *dst, int size)
167 Context *c = h->priv_data;
170 ret = ffurl_read(c->inner, dst, size);
171 c->inner_io_error = ret < 0 ? ret : 0;
176 static void *async_buffer_task(void *arg)
179 Context *c = h->priv_data;
180 RingBuffer *ring = &c->ring;
185 int fifo_space, to_copy;
187 pthread_mutex_lock(&c->mutex);
188 if (async_check_interrupt(h)) {
189 c->io_eof_reached = 1;
190 c->io_error = AVERROR_EXIT;
191 pthread_cond_signal(&c->cond_wakeup_main);
192 pthread_mutex_unlock(&c->mutex);
196 if (c->seek_request) {
197 seek_ret = ffurl_seek(c->inner, c->seek_pos, c->seek_whence);
199 c->io_eof_reached = 0;
204 c->seek_completed = 1;
205 c->seek_ret = seek_ret;
209 pthread_cond_signal(&c->cond_wakeup_main);
210 pthread_mutex_unlock(&c->mutex);
214 fifo_space = ring_space(ring);
215 if (c->io_eof_reached || fifo_space <= 0) {
216 pthread_cond_signal(&c->cond_wakeup_main);
217 pthread_cond_wait(&c->cond_wakeup_background, &c->mutex);
218 pthread_mutex_unlock(&c->mutex);
221 pthread_mutex_unlock(&c->mutex);
223 to_copy = FFMIN(4096, fifo_space);
224 ret = ring_generic_write(ring, (void *)h, to_copy, wrapped_url_read);
226 pthread_mutex_lock(&c->mutex);
228 c->io_eof_reached = 1;
229 if (c->inner_io_error < 0)
230 c->io_error = c->inner_io_error;
233 pthread_cond_signal(&c->cond_wakeup_main);
234 pthread_mutex_unlock(&c->mutex);
240 static int async_open(URLContext *h, const char *arg, int flags, AVDictionary **options)
242 Context *c = h->priv_data;
244 AVIOInterruptCB interrupt_callback = {.callback = async_check_interrupt, .opaque = h};
246 av_strstart(arg, "async:", &arg);
248 ret = ring_init(&c->ring, BUFFER_CAPACITY, READ_BACK_CAPACITY);
252 /* wrap interrupt callback */
253 c->interrupt_callback = h->interrupt_callback;
254 ret = ffurl_open_whitelist(&c->inner, arg, flags, &interrupt_callback, options, h->protocol_whitelist, h->protocol_blacklist, h);
256 av_log(h, AV_LOG_ERROR, "ffurl_open failed : %s, %s\n", av_err2str(ret), arg);
260 c->logical_size = ffurl_size(c->inner);
261 h->is_streamed = c->inner->is_streamed;
263 ret = pthread_mutex_init(&c->mutex, NULL);
265 av_log(h, AV_LOG_ERROR, "pthread_mutex_init failed : %s\n", av_err2str(ret));
269 ret = pthread_cond_init(&c->cond_wakeup_main, NULL);
271 av_log(h, AV_LOG_ERROR, "pthread_cond_init failed : %s\n", av_err2str(ret));
272 goto cond_wakeup_main_fail;
275 ret = pthread_cond_init(&c->cond_wakeup_background, NULL);
277 av_log(h, AV_LOG_ERROR, "pthread_cond_init failed : %s\n", av_err2str(ret));
278 goto cond_wakeup_background_fail;
281 ret = pthread_create(&c->async_buffer_thread, NULL, async_buffer_task, h);
283 av_log(h, AV_LOG_ERROR, "pthread_create failed : %s\n", av_err2str(ret));
290 pthread_cond_destroy(&c->cond_wakeup_background);
291 cond_wakeup_background_fail:
292 pthread_cond_destroy(&c->cond_wakeup_main);
293 cond_wakeup_main_fail:
294 pthread_mutex_destroy(&c->mutex);
296 ffurl_close(c->inner);
298 ring_destroy(&c->ring);
303 static int async_close(URLContext *h)
305 Context *c = h->priv_data;
308 pthread_mutex_lock(&c->mutex);
309 c->abort_request = 1;
310 pthread_cond_signal(&c->cond_wakeup_background);
311 pthread_mutex_unlock(&c->mutex);
313 ret = pthread_join(c->async_buffer_thread, NULL);
315 av_log(h, AV_LOG_ERROR, "pthread_join(): %s\n", av_err2str(ret));
317 pthread_cond_destroy(&c->cond_wakeup_background);
318 pthread_cond_destroy(&c->cond_wakeup_main);
319 pthread_mutex_destroy(&c->mutex);
320 ffurl_close(c->inner);
321 ring_destroy(&c->ring);
326 static int async_read_internal(URLContext *h, void *dest, int size, int read_complete,
327 void (*func)(void*, void*, int))
329 Context *c = h->priv_data;
330 RingBuffer *ring = &c->ring;
334 pthread_mutex_lock(&c->mutex);
336 while (to_read > 0) {
337 int fifo_size, to_copy;
338 if (async_check_interrupt(h)) {
342 fifo_size = ring_size(ring);
343 to_copy = FFMIN(to_read, fifo_size);
345 ring_generic_read(ring, dest, to_copy, func);
347 dest = (uint8_t *)dest + to_copy;
348 c->logical_pos += to_copy;
350 ret = size - to_read;
352 if (to_read <= 0 || !read_complete)
354 } else if (c->io_eof_reached) {
363 pthread_cond_signal(&c->cond_wakeup_background);
364 pthread_cond_wait(&c->cond_wakeup_main, &c->mutex);
367 pthread_cond_signal(&c->cond_wakeup_background);
368 pthread_mutex_unlock(&c->mutex);
373 static int async_read(URLContext *h, unsigned char *buf, int size)
375 return async_read_internal(h, buf, size, 0, NULL);
378 static void fifo_do_not_copy_func(void* dest, void* src, int size) {
382 static int64_t async_seek(URLContext *h, int64_t pos, int whence)
384 Context *c = h->priv_data;
385 RingBuffer *ring = &c->ring;
387 int64_t new_logical_pos;
389 int fifo_size_of_read_back;
391 if (whence == AVSEEK_SIZE) {
392 av_log(h, AV_LOG_TRACE, "async_seek: AVSEEK_SIZE: %"PRId64"\n", (int64_t)c->logical_size);
393 return c->logical_size;
394 } else if (whence == SEEK_CUR) {
395 av_log(h, AV_LOG_TRACE, "async_seek: %"PRId64"\n", pos);
396 new_logical_pos = pos + c->logical_pos;
397 } else if (whence == SEEK_SET){
398 av_log(h, AV_LOG_TRACE, "async_seek: %"PRId64"\n", pos);
399 new_logical_pos = pos;
401 return AVERROR(EINVAL);
403 if (new_logical_pos < 0)
404 return AVERROR(EINVAL);
406 fifo_size = ring_size(ring);
407 fifo_size_of_read_back = ring_size_of_read_back(ring);
408 if (new_logical_pos == c->logical_pos) {
409 /* current position */
410 return c->logical_pos;
411 } else if ((new_logical_pos >= (c->logical_pos - fifo_size_of_read_back)) &&
412 (new_logical_pos < (c->logical_pos + fifo_size + SHORT_SEEK_THRESHOLD))) {
413 int pos_delta = (int)(new_logical_pos - c->logical_pos);
415 av_log(h, AV_LOG_TRACE, "async_seek: fask_seek %"PRId64" from %d dist:%d/%d\n",
416 new_logical_pos, (int)c->logical_pos,
417 (int)(new_logical_pos - c->logical_pos), fifo_size);
420 // fast seek forwards
421 async_read_internal(h, NULL, pos_delta, 1, fifo_do_not_copy_func);
423 // fast seek backwards
424 ring_drain(ring, pos_delta);
425 c->logical_pos = new_logical_pos;
428 return c->logical_pos;
429 } else if (c->logical_size <= 0) {
431 return AVERROR(EINVAL);
432 } else if (new_logical_pos > c->logical_size) {
434 return AVERROR(EINVAL);
437 pthread_mutex_lock(&c->mutex);
440 c->seek_pos = new_logical_pos;
441 c->seek_whence = SEEK_SET;
442 c->seek_completed = 0;
446 if (async_check_interrupt(h)) {
450 if (c->seek_completed) {
451 if (c->seek_ret >= 0)
452 c->logical_pos = c->seek_ret;
456 pthread_cond_signal(&c->cond_wakeup_background);
457 pthread_cond_wait(&c->cond_wakeup_main, &c->mutex);
460 pthread_mutex_unlock(&c->mutex);
465 #define OFFSET(x) offsetof(Context, x)
466 #define D AV_OPT_FLAG_DECODING_PARAM
468 static const AVOption options[] = {
475 static const AVClass async_context_class = {
476 .class_name = "Async",
477 .item_name = av_default_item_name,
479 .version = LIBAVUTIL_VERSION_INT,
482 const URLProtocol ff_async_protocol = {
484 .url_open2 = async_open,
485 .url_read = async_read,
486 .url_seek = async_seek,
487 .url_close = async_close,
488 .priv_data_size = sizeof(Context),
489 .priv_data_class = &async_context_class,
494 #define TEST_SEEK_POS (1536)
495 #define TEST_STREAM_SIZE (2048)
497 typedef struct TestContext {
500 int64_t logical_size;
506 static int async_test_open(URLContext *h, const char *arg, int flags, AVDictionary **options)
508 TestContext *c = h->priv_data;
510 c->logical_size = TEST_STREAM_SIZE;
514 static int async_test_close(URLContext *h)
519 static int async_test_read(URLContext *h, unsigned char *buf, int size)
521 TestContext *c = h->priv_data;
525 if (c->opt_read_error)
526 return c->opt_read_error;
528 if (c->logical_pos >= c->logical_size)
531 for (i = 0; i < size; ++i) {
532 buf[i] = c->logical_pos & 0xFF;
537 if (c->logical_pos >= c->logical_size)
544 static int64_t async_test_seek(URLContext *h, int64_t pos, int whence)
546 TestContext *c = h->priv_data;
547 int64_t new_logical_pos;
549 if (whence == AVSEEK_SIZE) {
550 return c->logical_size;
551 } else if (whence == SEEK_CUR) {
552 new_logical_pos = pos + c->logical_pos;
553 } else if (whence == SEEK_SET){
554 new_logical_pos = pos;
556 return AVERROR(EINVAL);
558 if (new_logical_pos < 0)
559 return AVERROR(EINVAL);
561 c->logical_pos = new_logical_pos;
562 return new_logical_pos;
565 #define OFFSET(x) offsetof(TestContext, x)
566 #define D AV_OPT_FLAG_DECODING_PARAM
568 static const AVOption async_test_options[] = {
569 { "async-test-read-error", "cause read fail",
570 OFFSET(opt_read_error), AV_OPT_TYPE_INT, { .i64 = 0 }, INT_MIN, INT_MAX, .flags = D },
577 static const AVClass async_test_context_class = {
578 .class_name = "Async-Test",
579 .item_name = av_default_item_name,
580 .option = async_test_options,
581 .version = LIBAVUTIL_VERSION_INT,
584 const URLProtocol ff_async_test_protocol = {
585 .name = "async-test",
586 .url_open2 = async_test_open,
587 .url_read = async_test_read,
588 .url_seek = async_test_seek,
589 .url_close = async_test_close,
590 .priv_data_size = sizeof(TestContext),
591 .priv_data_class = &async_test_context_class,
596 URLContext *h = NULL;
602 unsigned char buf[4096];
603 AVDictionary *opts = NULL;
605 ffurl_register_protocol(&ff_async_protocol);
606 ffurl_register_protocol(&ff_async_test_protocol);
611 ret = ffurl_open(&h, "async:async-test:", AVIO_FLAG_READ, NULL, NULL);
612 printf("open: %d\n", ret);
614 size = ffurl_size(h);
615 printf("size: %"PRId64"\n", size);
617 pos = ffurl_seek(h, 0, SEEK_CUR);
620 ret = ffurl_read(h, buf, sizeof(buf));
621 if (ret == AVERROR_EOF) {
622 printf("read-error: AVERROR_EOF at %"PRId64"\n", ffurl_seek(h, 0, SEEK_CUR));
628 printf("read-error: %d at %"PRId64"\n", ret, ffurl_seek(h, 0, SEEK_CUR));
631 for (i = 0; i < ret; ++i) {
632 if (buf[i] != (pos & 0xFF)) {
633 printf("read-mismatch: actual %d, expecting %d, at %"PRId64"\n",
634 (int)buf[i], (int)(pos & 0xFF), pos);
643 printf("read: %"PRId64"\n", read_len);
648 ret = ffurl_read(h, buf, 1);
649 printf("read: %d\n", ret);
651 pos = ffurl_seek(h, TEST_SEEK_POS, SEEK_SET);
652 printf("seek: %"PRId64"\n", pos);
656 ret = ffurl_read(h, buf, sizeof(buf));
657 if (ret == AVERROR_EOF)
662 printf("read-error: %d at %"PRId64"\n", ret, ffurl_seek(h, 0, SEEK_CUR));
665 for (i = 0; i < ret; ++i) {
666 if (buf[i] != (pos & 0xFF)) {
667 printf("read-mismatch: actual %d, expecting %d, at %"PRId64"\n",
668 (int)buf[i], (int)(pos & 0xFF), pos);
677 printf("read: %"PRId64"\n", read_len);
679 ret = ffurl_read(h, buf, 1);
680 printf("read: %d\n", ret);
686 av_dict_set_int(&opts, "async-test-read-error", -10000, 0);
687 ret = ffurl_open(&h, "async:async-test:", AVIO_FLAG_READ, NULL, &opts);
688 printf("open: %d\n", ret);
690 ret = ffurl_read(h, buf, 1);
691 printf("read: %d\n", ret);