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-rw-r--r--libavformat/async.c699
1 files changed, 699 insertions, 0 deletions
diff --git a/libavformat/async.c b/libavformat/async.c
new file mode 100644
index 0000000000..54dbd2312a
--- /dev/null
+++ b/libavformat/async.c
@@ -0,0 +1,699 @@
+/*
+ * Input async protocol.
+ * Copyright (c) 2015 Zhang Rui <bbcallen@gmail.com>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg 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.
+ *
+ * FFmpeg 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Based on libavformat/cache.c by Michael Niedermayer
+ */
+
+ /**
+ * @TODO
+ * support timeout
+ * support work with concatdec, hls
+ */
+
+#include "libavutil/avassert.h"
+#include "libavutil/avstring.h"
+#include "libavutil/error.h"
+#include "libavutil/fifo.h"
+#include "libavutil/log.h"
+#include "libavutil/opt.h"
+#include "libavutil/thread.h"
+#include "url.h"
+#include <stdint.h>
+
+#if HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+
+#define BUFFER_CAPACITY (4 * 1024 * 1024)
+#define READ_BACK_CAPACITY (4 * 1024 * 1024)
+#define SHORT_SEEK_THRESHOLD (256 * 1024)
+
+typedef struct RingBuffer
+{
+ AVFifoBuffer *fifo;
+ int read_back_capacity;
+
+ int read_pos;
+} RingBuffer;
+
+typedef struct Context {
+ AVClass *class;
+ URLContext *inner;
+
+ int seek_request;
+ int64_t seek_pos;
+ int seek_whence;
+ int seek_completed;
+ int64_t seek_ret;
+
+ int inner_io_error;
+ int io_error;
+ int io_eof_reached;
+
+ int64_t logical_pos;
+ int64_t logical_size;
+ RingBuffer ring;
+
+ pthread_cond_t cond_wakeup_main;
+ pthread_cond_t cond_wakeup_background;
+ pthread_mutex_t mutex;
+ pthread_t async_buffer_thread;
+
+ int abort_request;
+ AVIOInterruptCB interrupt_callback;
+} Context;
+
+static int ring_init(RingBuffer *ring, unsigned int capacity, int read_back_capacity)
+{
+ memset(ring, 0, sizeof(RingBuffer));
+ ring->fifo = av_fifo_alloc(capacity + read_back_capacity);
+ if (!ring->fifo)
+ return AVERROR(ENOMEM);
+
+ ring->read_back_capacity = read_back_capacity;
+ return 0;
+}
+
+static void ring_destroy(RingBuffer *ring)
+{
+ av_fifo_freep(&ring->fifo);
+}
+
+static void ring_reset(RingBuffer *ring)
+{
+ av_fifo_reset(ring->fifo);
+ ring->read_pos = 0;
+}
+
+static int ring_size(RingBuffer *ring)
+{
+ return av_fifo_size(ring->fifo) - ring->read_pos;
+}
+
+static int ring_space(RingBuffer *ring)
+{
+ return av_fifo_space(ring->fifo);
+}
+
+static int ring_generic_read(RingBuffer *ring, void *dest, int buf_size, void (*func)(void*, void*, int))
+{
+ int ret;
+
+ av_assert2(buf_size <= ring_size(ring));
+ ret = av_fifo_generic_peek_at(ring->fifo, dest, ring->read_pos, buf_size, func);
+ ring->read_pos += buf_size;
+
+ if (ring->read_pos > ring->read_back_capacity) {
+ av_fifo_drain(ring->fifo, ring->read_pos - ring->read_back_capacity);
+ ring->read_pos = ring->read_back_capacity;
+ }
+
+ return ret;
+}
+
+static int ring_generic_write(RingBuffer *ring, void *src, int size, int (*func)(void*, void*, int))
+{
+ av_assert2(size <= ring_space(ring));
+ return av_fifo_generic_write(ring->fifo, src, size, func);
+}
+
+static int ring_size_of_read_back(RingBuffer *ring)
+{
+ return ring->read_pos;
+}
+
+static int ring_drain(RingBuffer *ring, int offset)
+{
+ av_assert2(offset >= -ring_size_of_read_back(ring));
+ av_assert2(offset <= -ring_size(ring));
+ ring->read_pos += offset;
+ return 0;
+}
+
+static int async_check_interrupt(void *arg)
+{
+ URLContext *h = arg;
+ Context *c = h->priv_data;
+
+ if (c->abort_request)
+ return 1;
+
+ if (ff_check_interrupt(&c->interrupt_callback))
+ c->abort_request = 1;
+
+ return c->abort_request;
+}
+
+static int wrapped_url_read(void *src, void *dst, int size)
+{
+ URLContext *h = src;
+ Context *c = h->priv_data;
+ int ret;
+
+ ret = ffurl_read(c->inner, dst, size);
+ c->inner_io_error = ret < 0 ? ret : 0;
+
+ return ret;
+}
+
+static void *async_buffer_task(void *arg)
+{
+ URLContext *h = arg;
+ Context *c = h->priv_data;
+ RingBuffer *ring = &c->ring;
+ int ret = 0;
+ int64_t seek_ret;
+
+ while (1) {
+ int fifo_space, to_copy;
+
+ pthread_mutex_lock(&c->mutex);
+ if (async_check_interrupt(h)) {
+ c->io_eof_reached = 1;
+ c->io_error = AVERROR_EXIT;
+ pthread_cond_signal(&c->cond_wakeup_main);
+ pthread_mutex_unlock(&c->mutex);
+ break;
+ }
+
+ if (c->seek_request) {
+ seek_ret = ffurl_seek(c->inner, c->seek_pos, c->seek_whence);
+ if (seek_ret >= 0) {
+ c->io_eof_reached = 0;
+ c->io_error = 0;
+ ring_reset(ring);
+ }
+
+ c->seek_completed = 1;
+ c->seek_ret = seek_ret;
+ c->seek_request = 0;
+
+
+ pthread_cond_signal(&c->cond_wakeup_main);
+ pthread_mutex_unlock(&c->mutex);
+ continue;
+ }
+
+ fifo_space = ring_space(ring);
+ if (c->io_eof_reached || fifo_space <= 0) {
+ pthread_cond_signal(&c->cond_wakeup_main);
+ pthread_cond_wait(&c->cond_wakeup_background, &c->mutex);
+ pthread_mutex_unlock(&c->mutex);
+ continue;
+ }
+ pthread_mutex_unlock(&c->mutex);
+
+ to_copy = FFMIN(4096, fifo_space);
+ ret = ring_generic_write(ring, (void *)h, to_copy, wrapped_url_read);
+
+ pthread_mutex_lock(&c->mutex);
+ if (ret <= 0) {
+ c->io_eof_reached = 1;
+ if (c->inner_io_error < 0)
+ c->io_error = c->inner_io_error;
+ }
+
+ pthread_cond_signal(&c->cond_wakeup_main);
+ pthread_mutex_unlock(&c->mutex);
+ }
+
+ return NULL;
+}
+
+static int async_open(URLContext *h, const char *arg, int flags, AVDictionary **options)
+{
+ Context *c = h->priv_data;
+ int ret;
+ AVIOInterruptCB interrupt_callback = {.callback = async_check_interrupt, .opaque = h};
+
+ av_strstart(arg, "async:", &arg);
+
+ ret = ring_init(&c->ring, BUFFER_CAPACITY, READ_BACK_CAPACITY);
+ if (ret < 0)
+ goto fifo_fail;
+
+ /* wrap interrupt callback */
+ c->interrupt_callback = h->interrupt_callback;
+ ret = ffurl_open_whitelist(&c->inner, arg, flags, &interrupt_callback, options, h->protocol_whitelist, h->protocol_blacklist, h);
+ if (ret != 0) {
+ av_log(h, AV_LOG_ERROR, "ffurl_open failed : %s, %s\n", av_err2str(ret), arg);
+ goto url_fail;
+ }
+
+ c->logical_size = ffurl_size(c->inner);
+ h->is_streamed = c->inner->is_streamed;
+
+ ret = pthread_mutex_init(&c->mutex, NULL);
+ if (ret != 0) {
+ av_log(h, AV_LOG_ERROR, "pthread_mutex_init failed : %s\n", av_err2str(ret));
+ goto mutex_fail;
+ }
+
+ ret = pthread_cond_init(&c->cond_wakeup_main, NULL);
+ if (ret != 0) {
+ av_log(h, AV_LOG_ERROR, "pthread_cond_init failed : %s\n", av_err2str(ret));
+ goto cond_wakeup_main_fail;
+ }
+
+ ret = pthread_cond_init(&c->cond_wakeup_background, NULL);
+ if (ret != 0) {
+ av_log(h, AV_LOG_ERROR, "pthread_cond_init failed : %s\n", av_err2str(ret));
+ goto cond_wakeup_background_fail;
+ }
+
+ ret = pthread_create(&c->async_buffer_thread, NULL, async_buffer_task, h);
+ if (ret) {
+ av_log(h, AV_LOG_ERROR, "pthread_create failed : %s\n", av_err2str(ret));
+ goto thread_fail;
+ }
+
+ return 0;
+
+thread_fail:
+ pthread_cond_destroy(&c->cond_wakeup_background);
+cond_wakeup_background_fail:
+ pthread_cond_destroy(&c->cond_wakeup_main);
+cond_wakeup_main_fail:
+ pthread_mutex_destroy(&c->mutex);
+mutex_fail:
+ ffurl_close(c->inner);
+url_fail:
+ ring_destroy(&c->ring);
+fifo_fail:
+ return ret;
+}
+
+static int async_close(URLContext *h)
+{
+ Context *c = h->priv_data;
+ int ret;
+
+ pthread_mutex_lock(&c->mutex);
+ c->abort_request = 1;
+ pthread_cond_signal(&c->cond_wakeup_background);
+ pthread_mutex_unlock(&c->mutex);
+
+ ret = pthread_join(c->async_buffer_thread, NULL);
+ if (ret != 0)
+ av_log(h, AV_LOG_ERROR, "pthread_join(): %s\n", av_err2str(ret));
+
+ pthread_cond_destroy(&c->cond_wakeup_background);
+ pthread_cond_destroy(&c->cond_wakeup_main);
+ pthread_mutex_destroy(&c->mutex);
+ ffurl_close(c->inner);
+ ring_destroy(&c->ring);
+
+ return 0;
+}
+
+static int async_read_internal(URLContext *h, void *dest, int size, int read_complete,
+ void (*func)(void*, void*, int))
+{
+ Context *c = h->priv_data;
+ RingBuffer *ring = &c->ring;
+ int to_read = size;
+ int ret = 0;
+
+ pthread_mutex_lock(&c->mutex);
+
+ while (to_read > 0) {
+ int fifo_size, to_copy;
+ if (async_check_interrupt(h)) {
+ ret = AVERROR_EXIT;
+ break;
+ }
+ fifo_size = ring_size(ring);
+ to_copy = FFMIN(to_read, fifo_size);
+ if (to_copy > 0) {
+ ring_generic_read(ring, dest, to_copy, func);
+ if (!func)
+ dest = (uint8_t *)dest + to_copy;
+ c->logical_pos += to_copy;
+ to_read -= to_copy;
+ ret = size - to_read;
+
+ if (to_read <= 0 || !read_complete)
+ break;
+ } else if (c->io_eof_reached) {
+ if (ret <= 0) {
+ if (c->io_error)
+ ret = c->io_error;
+ else
+ ret = AVERROR_EOF;
+ }
+ break;
+ }
+ pthread_cond_signal(&c->cond_wakeup_background);
+ pthread_cond_wait(&c->cond_wakeup_main, &c->mutex);
+ }
+
+ pthread_cond_signal(&c->cond_wakeup_background);
+ pthread_mutex_unlock(&c->mutex);
+
+ return ret;
+}
+
+static int async_read(URLContext *h, unsigned char *buf, int size)
+{
+ return async_read_internal(h, buf, size, 0, NULL);
+}
+
+static void fifo_do_not_copy_func(void* dest, void* src, int size) {
+ // do not copy
+}
+
+static int64_t async_seek(URLContext *h, int64_t pos, int whence)
+{
+ Context *c = h->priv_data;
+ RingBuffer *ring = &c->ring;
+ int64_t ret;
+ int64_t new_logical_pos;
+ int fifo_size;
+ int fifo_size_of_read_back;
+
+ if (whence == AVSEEK_SIZE) {
+ av_log(h, AV_LOG_TRACE, "async_seek: AVSEEK_SIZE: %"PRId64"\n", (int64_t)c->logical_size);
+ return c->logical_size;
+ } else if (whence == SEEK_CUR) {
+ av_log(h, AV_LOG_TRACE, "async_seek: %"PRId64"\n", pos);
+ new_logical_pos = pos + c->logical_pos;
+ } else if (whence == SEEK_SET){
+ av_log(h, AV_LOG_TRACE, "async_seek: %"PRId64"\n", pos);
+ new_logical_pos = pos;
+ } else {
+ return AVERROR(EINVAL);
+ }
+ if (new_logical_pos < 0)
+ return AVERROR(EINVAL);
+
+ fifo_size = ring_size(ring);
+ fifo_size_of_read_back = ring_size_of_read_back(ring);
+ if (new_logical_pos == c->logical_pos) {
+ /* current position */
+ return c->logical_pos;
+ } else if ((new_logical_pos >= (c->logical_pos - fifo_size_of_read_back)) &&
+ (new_logical_pos < (c->logical_pos + fifo_size + SHORT_SEEK_THRESHOLD))) {
+ int pos_delta = (int)(new_logical_pos - c->logical_pos);
+ /* fast seek */
+ av_log(h, AV_LOG_TRACE, "async_seek: fask_seek %"PRId64" from %d dist:%d/%d\n",
+ new_logical_pos, (int)c->logical_pos,
+ (int)(new_logical_pos - c->logical_pos), fifo_size);
+
+ if (pos_delta > 0) {
+ // fast seek forwards
+ async_read_internal(h, NULL, pos_delta, 1, fifo_do_not_copy_func);
+ } else {
+ // fast seek backwards
+ ring_drain(ring, pos_delta);
+ c->logical_pos = new_logical_pos;
+ }
+
+ return c->logical_pos;
+ } else if (c->logical_size <= 0) {
+ /* can not seek */
+ return AVERROR(EINVAL);
+ } else if (new_logical_pos > c->logical_size) {
+ /* beyond end */
+ return AVERROR(EINVAL);
+ }
+
+ pthread_mutex_lock(&c->mutex);
+
+ c->seek_request = 1;
+ c->seek_pos = new_logical_pos;
+ c->seek_whence = SEEK_SET;
+ c->seek_completed = 0;
+ c->seek_ret = 0;
+
+ while (1) {
+ if (async_check_interrupt(h)) {
+ ret = AVERROR_EXIT;
+ break;
+ }
+ if (c->seek_completed) {
+ if (c->seek_ret >= 0)
+ c->logical_pos = c->seek_ret;
+ ret = c->seek_ret;
+ break;
+ }
+ pthread_cond_signal(&c->cond_wakeup_background);
+ pthread_cond_wait(&c->cond_wakeup_main, &c->mutex);
+ }
+
+ pthread_mutex_unlock(&c->mutex);
+
+ return ret;
+}
+
+#define OFFSET(x) offsetof(Context, x)
+#define D AV_OPT_FLAG_DECODING_PARAM
+
+static const AVOption options[] = {
+ {NULL},
+};
+
+#undef D
+#undef OFFSET
+
+static const AVClass async_context_class = {
+ .class_name = "Async",
+ .item_name = av_default_item_name,
+ .option = options,
+ .version = LIBAVUTIL_VERSION_INT,
+};
+
+const URLProtocol ff_async_protocol = {
+ .name = "async",
+ .url_open2 = async_open,
+ .url_read = async_read,
+ .url_seek = async_seek,
+ .url_close = async_close,
+ .priv_data_size = sizeof(Context),
+ .priv_data_class = &async_context_class,
+};
+
+#if 0
+
+#define TEST_SEEK_POS (1536)
+#define TEST_STREAM_SIZE (2048)
+
+typedef struct TestContext {
+ AVClass *class;
+ int64_t logical_pos;
+ int64_t logical_size;
+
+ /* options */
+ int opt_read_error;
+} TestContext;
+
+static int async_test_open(URLContext *h, const char *arg, int flags, AVDictionary **options)
+{
+ TestContext *c = h->priv_data;
+ c->logical_pos = 0;
+ c->logical_size = TEST_STREAM_SIZE;
+ return 0;
+}
+
+static int async_test_close(URLContext *h)
+{
+ return 0;
+}
+
+static int async_test_read(URLContext *h, unsigned char *buf, int size)
+{
+ TestContext *c = h->priv_data;
+ int i;
+ int read_len = 0;
+
+ if (c->opt_read_error)
+ return c->opt_read_error;
+
+ if (c->logical_pos >= c->logical_size)
+ return AVERROR_EOF;
+
+ for (i = 0; i < size; ++i) {
+ buf[i] = c->logical_pos & 0xFF;
+
+ c->logical_pos++;
+ read_len++;
+
+ if (c->logical_pos >= c->logical_size)
+ break;
+ }
+
+ return read_len;
+}
+
+static int64_t async_test_seek(URLContext *h, int64_t pos, int whence)
+{
+ TestContext *c = h->priv_data;
+ int64_t new_logical_pos;
+
+ if (whence == AVSEEK_SIZE) {
+ return c->logical_size;
+ } else if (whence == SEEK_CUR) {
+ new_logical_pos = pos + c->logical_pos;
+ } else if (whence == SEEK_SET){
+ new_logical_pos = pos;
+ } else {
+ return AVERROR(EINVAL);
+ }
+ if (new_logical_pos < 0)
+ return AVERROR(EINVAL);
+
+ c->logical_pos = new_logical_pos;
+ return new_logical_pos;
+}
+
+#define OFFSET(x) offsetof(TestContext, x)
+#define D AV_OPT_FLAG_DECODING_PARAM
+
+static const AVOption async_test_options[] = {
+ { "async-test-read-error", "cause read fail",
+ OFFSET(opt_read_error), AV_OPT_TYPE_INT, { .i64 = 0 }, INT_MIN, INT_MAX, .flags = D },
+ {NULL},
+};
+
+#undef D
+#undef OFFSET
+
+static const AVClass async_test_context_class = {
+ .class_name = "Async-Test",
+ .item_name = av_default_item_name,
+ .option = async_test_options,
+ .version = LIBAVUTIL_VERSION_INT,
+};
+
+const URLProtocol ff_async_test_protocol = {
+ .name = "async-test",
+ .url_open2 = async_test_open,
+ .url_read = async_test_read,
+ .url_seek = async_test_seek,
+ .url_close = async_test_close,
+ .priv_data_size = sizeof(TestContext),
+ .priv_data_class = &async_test_context_class,
+};
+
+int main(void)
+{
+ URLContext *h = NULL;
+ int i;
+ int ret;
+ int64_t size;
+ int64_t pos;
+ int64_t read_len;
+ unsigned char buf[4096];
+ AVDictionary *opts = NULL;
+
+ ffurl_register_protocol(&ff_async_protocol);
+ ffurl_register_protocol(&ff_async_test_protocol);
+
+ /*
+ * test normal read
+ */
+ ret = ffurl_open(&h, "async:async-test:", AVIO_FLAG_READ, NULL, NULL);
+ printf("open: %d\n", ret);
+
+ size = ffurl_size(h);
+ printf("size: %"PRId64"\n", size);
+
+ pos = ffurl_seek(h, 0, SEEK_CUR);
+ read_len = 0;
+ while (1) {
+ ret = ffurl_read(h, buf, sizeof(buf));
+ if (ret == AVERROR_EOF) {
+ printf("read-error: AVERROR_EOF at %"PRId64"\n", ffurl_seek(h, 0, SEEK_CUR));
+ break;
+ }
+ else if (ret == 0)
+ break;
+ else if (ret < 0) {
+ printf("read-error: %d at %"PRId64"\n", ret, ffurl_seek(h, 0, SEEK_CUR));
+ goto fail;
+ } else {
+ for (i = 0; i < ret; ++i) {
+ if (buf[i] != (pos & 0xFF)) {
+ printf("read-mismatch: actual %d, expecting %d, at %"PRId64"\n",
+ (int)buf[i], (int)(pos & 0xFF), pos);
+ break;
+ }
+ pos++;
+ }
+ }
+
+ read_len += ret;
+ }
+ printf("read: %"PRId64"\n", read_len);
+
+ /*
+ * test normal seek
+ */
+ ret = ffurl_read(h, buf, 1);
+ printf("read: %d\n", ret);
+
+ pos = ffurl_seek(h, TEST_SEEK_POS, SEEK_SET);
+ printf("seek: %"PRId64"\n", pos);
+
+ read_len = 0;
+ while (1) {
+ ret = ffurl_read(h, buf, sizeof(buf));
+ if (ret == AVERROR_EOF)
+ break;
+ else if (ret == 0)
+ break;
+ else if (ret < 0) {
+ printf("read-error: %d at %"PRId64"\n", ret, ffurl_seek(h, 0, SEEK_CUR));
+ goto fail;
+ } else {
+ for (i = 0; i < ret; ++i) {
+ if (buf[i] != (pos & 0xFF)) {
+ printf("read-mismatch: actual %d, expecting %d, at %"PRId64"\n",
+ (int)buf[i], (int)(pos & 0xFF), pos);
+ break;
+ }
+ pos++;
+ }
+ }
+
+ read_len += ret;
+ }
+ printf("read: %"PRId64"\n", read_len);
+
+ ret = ffurl_read(h, buf, 1);
+ printf("read: %d\n", ret);
+
+ /*
+ * test read error
+ */
+ ffurl_close(h);
+ av_dict_set_int(&opts, "async-test-read-error", -10000, 0);
+ ret = ffurl_open(&h, "async:async-test:", AVIO_FLAG_READ, NULL, &opts);
+ printf("open: %d\n", ret);
+
+ ret = ffurl_read(h, buf, 1);
+ printf("read: %d\n", ret);
+
+fail:
+ av_dict_free(&opts);
+ ffurl_close(h);
+ return 0;
+}
+
+#endif
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