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mpv/demux/demux.c
wm4 f9f2e1cc4e demux: hack for instant stream switching
This removes the delay when switching audio tracks in mkv or mp4 files.
Other formats are not enabled, because it's not clear whether the
demuxers fulfill the requirements listed in demux.h. (Many formats
definitely do not with libavformat.)

Background:

The demuxer packet cache buffers a certain amount of packets. This
includes only packets from selected streams. We discard packets from
other streams for various reasons. This introduces a problem: switching
to a different audio track introduces a delay. The delay is as big as
the demuxer packet cache buffer, because while the file was read ahead
to fill the packet buffer, the process of reading packets also discarded
all packets from the previously not selected audio stream. Once the
remaining packet buffer has been played, new audio packets are available
and you hear audio again.

We could probably just not discard packets from unselected streams. But
this would require additional memory and CPU resources, and also it's
hard to tell when packets from unused streams should be discarded (we
don't want to keep them forever; it'd be a memory leak).

We could also issue a player hr-seek to the current playback position,
which would solve the problem in 1 line of code or so. But this can be
rather slow.

So what we do in this commit instead is: we just seek back to the
position where our current packet buffer starts, and start demuxing from
this position again. This way we can get the "past" packets for the
newly selected stream. For streams which were already selected the
packets are simply discarded until the previous position is reached
again.

That latter part is the hard part. We really want to skip packets
exactly until the position where we left off previously, or we will skip
packets or feed packets to the decoder twice. If we assume that the
demuxer is deterministic (returns exactly the same packets after a seek
to a previous position), then we can try to check whether it's the same
packet as the one at the end of the packet buffer. If it is, we know
that the packet after it is where we left off last time.

Unfortunately, this is not very robust, and maybe it can't be made
robust. Currently we use the demux_packet.pos field as unique packet
ID - which works fine in some scenarios, but will break in arbitrary
ways if the basic requirement to the demuxer (as listed in the demux.h
additions) are broken. Thus, this is enabled only for the internal mkv
demuxer and the libavformat mp4 demuxer.

(libavformat mkv does not work, because the packet positions are not
unique. Probably could be fixed upstream, but it's not clear whether
it's a bug or a feature.)
2015-02-13 21:17:17 +01:00

1466 lines
47 KiB
C

/*
* This file is part of MPlayer.
*
* MPlayer is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* MPlayer 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 General Public License along
* with MPlayer; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <unistd.h>
#include <pthread.h>
#include <math.h>
#include <sys/types.h>
#include <sys/stat.h>
#include "config.h"
#include "options/options.h"
#include "talloc.h"
#include "common/msg.h"
#include "common/global.h"
#include "osdep/threads.h"
#include "stream/stream.h"
#include "demux.h"
#include "stheader.h"
#include "audio/format.h"
// Demuxer list
extern const struct demuxer_desc demuxer_desc_edl;
extern const struct demuxer_desc demuxer_desc_cue;
extern const demuxer_desc_t demuxer_desc_rawaudio;
extern const demuxer_desc_t demuxer_desc_rawvideo;
extern const demuxer_desc_t demuxer_desc_tv;
extern const demuxer_desc_t demuxer_desc_mf;
extern const demuxer_desc_t demuxer_desc_matroska;
extern const demuxer_desc_t demuxer_desc_lavf;
extern const demuxer_desc_t demuxer_desc_libass;
extern const demuxer_desc_t demuxer_desc_subreader;
extern const demuxer_desc_t demuxer_desc_playlist;
extern const demuxer_desc_t demuxer_desc_disc;
/* Please do not add any new demuxers here. If you want to implement a new
* demuxer, add it to libavformat, except for wrappers around external
* libraries and demuxers requiring binary support. */
const demuxer_desc_t *const demuxer_list[] = {
&demuxer_desc_disc,
&demuxer_desc_edl,
&demuxer_desc_cue,
&demuxer_desc_rawaudio,
&demuxer_desc_rawvideo,
#if HAVE_TV
&demuxer_desc_tv,
#endif
#if HAVE_LIBASS
&demuxer_desc_libass,
#endif
&demuxer_desc_matroska,
&demuxer_desc_lavf,
&demuxer_desc_mf,
&demuxer_desc_playlist,
// Pretty aggressive, so should be last.
&demuxer_desc_subreader,
NULL
};
struct demux_internal {
struct mp_log *log;
// The demuxer runs potentially in another thread, so we keep two demuxer
// structs; the real demuxer can access the shadow struct only.
// Since demuxer and user threads both don't use locks, a third demuxer
// struct d_buffer is used to copy data between them in a synchronized way.
struct demuxer *d_thread; // accessed by demuxer impl. (producer)
struct demuxer *d_user; // accessed by player (consumer)
struct demuxer *d_buffer; // protected by lock; used to sync d_user/thread
// The lock protects the packet queues (struct demux_stream), d_buffer,
// and some minor fields like thread_paused.
pthread_mutex_t lock;
pthread_cond_t wakeup;
pthread_t thread;
// -- All the following fields are protected by lock.
bool thread_paused;
int thread_request_pause; // counter, if >0, make demuxer thread pause
bool thread_terminate;
bool threading;
void (*wakeup_cb)(void *ctx);
void *wakeup_cb_ctx;
bool warned_queue_overflow;
bool last_eof; // last actual global EOF status
bool eof; // whether we're in EOF state (reset for retry)
bool idle;
bool autoselect;
double min_secs;
int min_packs;
int min_bytes;
bool tracks_switched; // thread needs to inform demuxer of this
bool seeking; // there's a seek queued
int seek_flags; // flags for next seek (if seeking==true)
double seek_pts;
bool refresh_seeks_enabled;
bool start_refresh_seek;
// Cached state.
bool force_cache_update;
double time_length;
struct mp_nav_event *nav_event;
struct mp_tags *stream_metadata;
int64_t stream_size;
int64_t stream_cache_size;
int64_t stream_cache_fill;
int stream_cache_idle;
// Updated during init only.
char *stream_base_filename;
};
struct demux_stream {
struct demux_internal *in;
enum stream_type type;
// all fields are protected by in->lock
bool selected; // user wants packets from this stream
bool active; // try to keep at least 1 packet queued
bool eof; // end of demuxed stream? (true if all buffer empty)
bool refreshing;
size_t packs; // number of packets in buffer
size_t bytes; // total bytes of packets in buffer
double base_ts; // timestamp of the last packet returned to decoder
double last_ts; // timestamp of the last packet added to queue
double last_br_ts; // timestamp of last packet bitrate was calculated
size_t last_br_bytes; // summed packet sizes since last bitrate calculation
double bitrate;
int64_t last_pos;
struct demux_packet *head;
struct demux_packet *tail;
};
// Return "a", or if that is NOPTS, return "def".
#define PTS_OR_DEF(a, def) ((a) == MP_NOPTS_VALUE ? (def) : (a))
// If one of the values is NOPTS, always pick the other one.
#define MP_PTS_MIN(a, b) MPMIN(PTS_OR_DEF(a, b), PTS_OR_DEF(b, a))
#define MP_PTS_MAX(a, b) MPMAX(PTS_OR_DEF(a, b), PTS_OR_DEF(b, a))
static void demuxer_sort_chapters(demuxer_t *demuxer);
static void *demux_thread(void *pctx);
static void update_cache(struct demux_internal *in);
// called locked
static void ds_flush(struct demux_stream *ds)
{
demux_packet_t *dp = ds->head;
while (dp) {
demux_packet_t *dn = dp->next;
free_demux_packet(dp);
dp = dn;
}
ds->head = ds->tail = NULL;
ds->packs = 0;
ds->bytes = 0;
ds->last_ts = ds->base_ts = ds->last_br_ts = MP_NOPTS_VALUE;
ds->last_br_bytes = 0;
ds->bitrate = -1;
ds->eof = false;
ds->active = false;
ds->refreshing = false;
ds->last_pos = -1;
}
struct sh_stream *new_sh_stream(demuxer_t *demuxer, enum stream_type type)
{
assert(demuxer == demuxer->in->d_thread);
if (demuxer->num_streams > MAX_SH_STREAMS) {
MP_WARN(demuxer, "Too many streams.\n");
return NULL;
}
int demuxer_id = 0;
for (int n = 0; n < demuxer->num_streams; n++) {
if (demuxer->streams[n]->type == type)
demuxer_id++;
}
struct sh_stream *sh = talloc_ptrtype(demuxer, sh);
*sh = (struct sh_stream) {
.type = type,
.index = demuxer->num_streams,
.ff_index = demuxer->num_streams,
.demuxer_id = demuxer_id, // may be overwritten by demuxer
.ds = talloc(sh, struct demux_stream),
};
*sh->ds = (struct demux_stream) {
.in = demuxer->in,
.type = sh->type,
.selected = demuxer->in->autoselect,
};
MP_TARRAY_APPEND(demuxer, demuxer->streams, demuxer->num_streams, sh);
switch (sh->type) {
case STREAM_VIDEO: sh->video = talloc_zero(demuxer, struct sh_video); break;
case STREAM_AUDIO: sh->audio = talloc_zero(demuxer, struct sh_audio); break;
case STREAM_SUB: sh->sub = talloc_zero(demuxer, struct sh_sub); break;
}
return sh;
}
void free_demuxer(demuxer_t *demuxer)
{
if (!demuxer)
return;
struct demux_internal *in = demuxer->in;
assert(demuxer == in->d_user);
demux_stop_thread(demuxer);
if (demuxer->desc->close)
demuxer->desc->close(in->d_thread);
for (int n = 0; n < demuxer->num_streams; n++)
ds_flush(demuxer->streams[n]->ds);
pthread_mutex_destroy(&in->lock);
pthread_cond_destroy(&in->wakeup);
talloc_free(in->nav_event);
talloc_free(demuxer);
}
// Start the demuxer thread, which reads ahead packets on its own.
void demux_start_thread(struct demuxer *demuxer)
{
struct demux_internal *in = demuxer->in;
assert(demuxer == in->d_user);
if (!in->threading) {
in->threading = true;
if (pthread_create(&in->thread, NULL, demux_thread, in))
in->threading = false;
}
}
void demux_stop_thread(struct demuxer *demuxer)
{
struct demux_internal *in = demuxer->in;
assert(demuxer == in->d_user);
if (in->threading) {
pthread_mutex_lock(&in->lock);
in->thread_terminate = true;
pthread_cond_signal(&in->wakeup);
pthread_mutex_unlock(&in->lock);
pthread_join(in->thread, NULL);
in->threading = false;
in->thread_terminate = false;
}
}
// The demuxer thread will call cb(ctx) if there's a new packet, or EOF is reached.
void demux_set_wakeup_cb(struct demuxer *demuxer, void (*cb)(void *ctx), void *ctx)
{
struct demux_internal *in = demuxer->in;
pthread_mutex_lock(&in->lock);
in->wakeup_cb = cb;
in->wakeup_cb_ctx = ctx;
pthread_mutex_unlock(&in->lock);
}
const char *stream_type_name(enum stream_type type)
{
switch (type) {
case STREAM_VIDEO: return "video";
case STREAM_AUDIO: return "audio";
case STREAM_SUB: return "sub";
default: return "unknown";
}
}
// Returns the same value as demuxer->fill_buffer: 1 ok, 0 EOF/not selected.
int demux_add_packet(struct sh_stream *stream, demux_packet_t *dp)
{
struct demux_stream *ds = stream ? stream->ds : NULL;
if (!dp || !ds) {
talloc_free(dp);
return 0;
}
struct demux_internal *in = ds->in;
pthread_mutex_lock(&in->lock);
bool drop = false;
if (ds->refreshing) {
// Resume reading once the old position was reached (i.e. we start
// returning packets where we left off before the refresh).
drop = true;
if (dp->pos == ds->last_pos)
ds->refreshing = false;
}
if (!ds->selected || in->seeking || drop) {
pthread_mutex_unlock(&in->lock);
talloc_free(dp);
return 0;
}
dp->stream = stream->index;
dp->next = NULL;
ds->last_pos = dp->pos;
ds->packs++;
ds->bytes += dp->len;
if (ds->tail) {
// next packet in stream
ds->tail->next = dp;
ds->tail = dp;
} else {
// first packet in stream
ds->head = ds->tail = dp;
}
// obviously not true anymore
ds->eof = false;
in->last_eof = in->eof = false;
// For video, PTS determination is not trivial, but for other media types
// distinguishing PTS and DTS is not useful.
if (stream->type != STREAM_VIDEO && dp->pts == MP_NOPTS_VALUE)
dp->pts = dp->dts;
double ts = dp->dts == MP_NOPTS_VALUE ? dp->pts : dp->dts;
if (ts != MP_NOPTS_VALUE && (ts > ds->last_ts || ts + 10 < ds->last_ts))
ds->last_ts = ts;
if (ds->base_ts == MP_NOPTS_VALUE)
ds->base_ts = ds->last_ts;
MP_DBG(in, "append packet to %s: size=%d pts=%f dts=%f pos=%"PRIi64" "
"[num=%zd size=%zd]\n", stream_type_name(stream->type),
dp->len, dp->pts, dp->dts, dp->pos, ds->packs, ds->bytes);
if (ds->in->wakeup_cb && !ds->head->next)
ds->in->wakeup_cb(ds->in->wakeup_cb_ctx);
pthread_cond_signal(&in->wakeup);
pthread_mutex_unlock(&in->lock);
return 1;
}
// Returns true if there was "progress" (lock was released temporarily).
static bool read_packet(struct demux_internal *in)
{
in->eof = false;
in->idle = true;
// Check if we need to read a new packet. We do this if all queues are below
// the minimum, or if a stream explicitly needs new packets. Also includes
// safe-guards against packet queue overflow.
bool active = false, read_more = false;
size_t packs = 0, bytes = 0;
for (int n = 0; n < in->d_buffer->num_streams; n++) {
struct demux_stream *ds = in->d_buffer->streams[n]->ds;
active |= ds->active;
read_more |= ds->active && !ds->head;
packs += ds->packs;
bytes += ds->bytes;
if (ds->active && ds->last_ts != MP_NOPTS_VALUE && in->min_secs > 0)
read_more |= ds->last_ts - ds->base_ts < in->min_secs;
}
MP_DBG(in, "packets=%zd, bytes=%zd, active=%d, more=%d\n",
packs, bytes, active, read_more);
if (packs >= MAX_PACKS || bytes >= MAX_PACK_BYTES) {
if (!in->warned_queue_overflow) {
in->warned_queue_overflow = true;
MP_ERR(in, "Too many packets in the demuxer packet queues:\n");
for (int n = 0; n < in->d_buffer->num_streams; n++) {
struct demux_stream *ds = in->d_buffer->streams[n]->ds;
if (ds->selected) {
MP_ERR(in, " %s/%d: %zd packets, %zd bytes\n",
stream_type_name(ds->type), n, ds->packs, ds->bytes);
}
}
}
for (int n = 0; n < in->d_buffer->num_streams; n++) {
struct demux_stream *ds = in->d_buffer->streams[n]->ds;
ds->eof |= !ds->head;
}
pthread_cond_signal(&in->wakeup);
return false;
}
if (packs < in->min_packs && bytes < in->min_bytes)
read_more |= active;
if (!read_more)
return false;
// Actually read a packet. Drop the lock while doing so, because waiting
// for disk or network I/O can take time.
in->idle = false;
pthread_mutex_unlock(&in->lock);
struct demuxer *demux = in->d_thread;
bool eof = !demux->desc->fill_buffer || demux->desc->fill_buffer(demux) <= 0;
update_cache(in);
pthread_mutex_lock(&in->lock);
if (eof) {
for (int n = 0; n < in->d_buffer->num_streams; n++) {
struct demux_stream *ds = in->d_buffer->streams[n]->ds;
ds->eof = true;
ds->active = false;
}
// If we had EOF previously, then don't wakeup (avoids wakeup loop)
if (!in->last_eof) {
if (in->wakeup_cb)
in->wakeup_cb(in->wakeup_cb_ctx);
pthread_cond_signal(&in->wakeup);
MP_VERBOSE(in, "EOF reached.\n");
}
}
in->eof = in->last_eof = eof;
return true;
}
// must be called locked; may temporarily unlock
static void ds_get_packets(struct demux_stream *ds)
{
const char *t = stream_type_name(ds->type);
struct demux_internal *in = ds->in;
MP_DBG(in, "reading packet for %s\n", t);
in->eof = false; // force retry
ds->eof = false;
while (ds->selected && !ds->head && !ds->eof) {
ds->active = true;
// Note: the following code marks EOF if it can't continue
if (in->threading) {
MP_VERBOSE(in, "waiting for demux thread (%s)\n", t);
pthread_cond_signal(&in->wakeup);
pthread_cond_wait(&in->wakeup, &in->lock);
} else {
read_packet(in);
}
}
}
// An obscure mechanism to get stream switching to be executed faster.
// On a switch, it seeks back, and then grabs all packets that were
// "missing" from the packet queue of the newly selected stream.
static void start_refreshing(struct demux_internal *in)
{
struct demuxer *demux = in->d_thread;
in->start_refresh_seek = false;
double start_ts = MP_NOPTS_VALUE;
for (int n = 0; n < demux->num_streams; n++) {
struct demux_stream *ds = demux->streams[n]->ds;
if (ds->type == STREAM_VIDEO || ds->type == STREAM_AUDIO)
start_ts = MP_PTS_MIN(start_ts, ds->base_ts);
}
if (start_ts == MP_NOPTS_VALUE || !demux->desc->seek || !demux->seekable ||
demux->partially_seekable || !demux->allow_refresh_seeks)
return;
for (int n = 0; n < demux->num_streams; n++) {
struct demux_stream *ds = demux->streams[n]->ds;
// Streams which didn't read any packets yet can return all packets,
// or they'd be stuck forever; affects newly selected streams too.
if (ds->last_pos != -1)
ds->refreshing = true;
}
pthread_mutex_unlock(&in->lock);
// Seek back to player's current position, with a small offset added.
in->d_thread->desc->seek(in->d_thread, start_ts - 1.0,
SEEK_ABSOLUTE | SEEK_BACKWARD | SEEK_SUBPREROLL);
pthread_mutex_lock(&in->lock);
}
static void execute_trackswitch(struct demux_internal *in)
{
in->tracks_switched = false;
pthread_mutex_unlock(&in->lock);
if (in->d_thread->desc->control)
in->d_thread->desc->control(in->d_thread, DEMUXER_CTRL_SWITCHED_TRACKS, 0);
pthread_mutex_lock(&in->lock);
if (in->start_refresh_seek)
start_refreshing(in);
}
static void execute_seek(struct demux_internal *in)
{
int flags = in->seek_flags;
double pts = in->seek_pts;
in->seeking = false;
pthread_mutex_unlock(&in->lock);
if (in->d_thread->desc->seek)
in->d_thread->desc->seek(in->d_thread, pts, flags);
pthread_mutex_lock(&in->lock);
}
static void *demux_thread(void *pctx)
{
struct demux_internal *in = pctx;
mpthread_set_name("demux");
pthread_mutex_lock(&in->lock);
while (!in->thread_terminate) {
in->thread_paused = in->thread_request_pause > 0;
if (in->thread_paused) {
pthread_cond_signal(&in->wakeup);
pthread_cond_wait(&in->wakeup, &in->lock);
continue;
}
if (in->tracks_switched) {
execute_trackswitch(in);
continue;
}
if (in->seeking) {
execute_seek(in);
continue;
}
if (!in->eof) {
if (read_packet(in))
continue; // read_packet unlocked, so recheck conditions
}
if (in->force_cache_update) {
pthread_mutex_unlock(&in->lock);
update_cache(in);
pthread_mutex_lock(&in->lock);
in->force_cache_update = false;
continue;
}
pthread_cond_signal(&in->wakeup);
pthread_cond_wait(&in->wakeup, &in->lock);
}
pthread_mutex_unlock(&in->lock);
return NULL;
}
static struct demux_packet *dequeue_packet(struct demux_stream *ds)
{
if (!ds->head)
return NULL;
struct demux_packet *pkt = ds->head;
ds->head = pkt->next;
pkt->next = NULL;
if (!ds->head)
ds->tail = NULL;
ds->bytes -= pkt->len;
ds->packs--;
double ts = pkt->dts == MP_NOPTS_VALUE ? pkt->pts : pkt->dts;
if (ts != MP_NOPTS_VALUE)
ds->base_ts = ts;
if (pkt->keyframe) {
// Update bitrate - only at keyframe points, because we use the
// (possibly) reordered packet timestamps instead of realtime.
double d = ts - ds->last_br_ts;
if (ts == MP_NOPTS_VALUE || ds->last_br_ts == MP_NOPTS_VALUE || d < 0) {
ds->bitrate = -1;
ds->last_br_ts = ts;
ds->last_br_bytes = 0;
} else if (d > 0 && d >= 0.5) { // a window of least 500ms for UI purposes
ds->bitrate = ds->last_br_bytes / d;
ds->last_br_ts = ts;
ds->last_br_bytes = 0;
}
}
ds->last_br_bytes += pkt->len;
// This implies this function is actually called from "the" user thread.
if (pkt->pos >= ds->in->d_user->filepos)
ds->in->d_user->filepos = pkt->pos;
return pkt;
}
// Read a packet from the given stream. The returned packet belongs to the
// caller, who has to free it with talloc_free(). Might block. Returns NULL
// on EOF.
struct demux_packet *demux_read_packet(struct sh_stream *sh)
{
struct demux_stream *ds = sh ? sh->ds : NULL;
struct demux_packet *pkt = NULL;
if (ds) {
pthread_mutex_lock(&ds->in->lock);
ds_get_packets(ds);
pkt = dequeue_packet(ds);
pthread_cond_signal(&ds->in->wakeup); // possibly read more
pthread_mutex_unlock(&ds->in->lock);
}
return pkt;
}
// Poll the demuxer queue, and if there's a packet, return it. Otherwise, just
// make the demuxer thread read packets for this stream, and if there's at
// least one packet, call the wakeup callback.
// Unlike demux_read_packet(), this always enables readahead (which means you
// must not use it on interleaved subtitle streams).
// Returns:
// < 0: EOF was reached, *out_pkt=NULL
// == 0: no new packet yet, but maybe later, *out_pkt=NULL
// > 0: new packet read, *out_pkt is set
int demux_read_packet_async(struct sh_stream *sh, struct demux_packet **out_pkt)
{
struct demux_stream *ds = sh ? sh->ds : NULL;
int r = -1;
*out_pkt = NULL;
if (ds) {
if (ds->in->threading) {
pthread_mutex_lock(&ds->in->lock);
*out_pkt = dequeue_packet(ds);
r = *out_pkt ? 1 : ((ds->eof || !ds->selected) ? -1 : 0);
ds->active = ds->selected; // enable readahead
ds->in->eof = false; // force retry
pthread_cond_signal(&ds->in->wakeup); // possibly read more
pthread_mutex_unlock(&ds->in->lock);
} else {
*out_pkt = demux_read_packet(sh);
r = *out_pkt ? 1 : -1;
}
}
return r;
}
// Return the pts of the next packet that demux_read_packet() would return.
// Might block. Sometimes used to force a packet read, without removing any
// packets from the queue.
double demux_get_next_pts(struct sh_stream *sh)
{
double res = MP_NOPTS_VALUE;
if (sh) {
pthread_mutex_lock(&sh->ds->in->lock);
ds_get_packets(sh->ds);
if (sh->ds->head)
res = sh->ds->head->pts;
pthread_mutex_unlock(&sh->ds->in->lock);
}
return res;
}
// Return whether a packet is queued. Never blocks, never forces any reads.
bool demux_has_packet(struct sh_stream *sh)
{
bool has_packet = false;
if (sh) {
pthread_mutex_lock(&sh->ds->in->lock);
has_packet = sh->ds->head;
pthread_mutex_unlock(&sh->ds->in->lock);
}
return has_packet;
}
// Read and return any packet we find.
struct demux_packet *demux_read_any_packet(struct demuxer *demuxer)
{
assert(!demuxer->in->threading); // doesn't work with threading
bool read_more = true;
while (read_more) {
for (int n = 0; n < demuxer->num_streams; n++) {
struct sh_stream *sh = demuxer->streams[n];
sh->ds->active = sh->ds->selected; // force read_packet() to read
struct demux_packet *pkt = dequeue_packet(sh->ds);
if (pkt)
return pkt;
}
// retry after calling this
pthread_mutex_lock(&demuxer->in->lock);
read_more = read_packet(demuxer->in);
read_more &= !demuxer->in->eof;
pthread_mutex_unlock(&demuxer->in->lock);
}
return NULL;
}
// ====================================================================
void demuxer_help(struct mp_log *log)
{
int i;
mp_info(log, "Available demuxers:\n");
mp_info(log, " demuxer: info:\n");
for (i = 0; demuxer_list[i]; i++) {
mp_info(log, "%10s %s\n",
demuxer_list[i]->name, demuxer_list[i]->desc);
}
}
static const char *d_level(enum demux_check level)
{
switch (level) {
case DEMUX_CHECK_FORCE: return "force";
case DEMUX_CHECK_UNSAFE: return "unsafe";
case DEMUX_CHECK_REQUEST:return "request";
case DEMUX_CHECK_NORMAL: return "normal";
}
abort();
}
static int decode_float(char *str, float *out)
{
char *rest;
float dec_val;
dec_val = strtod(str, &rest);
if (!rest || (rest == str) || !isfinite(dec_val))
return -1;
*out = dec_val;
return 0;
}
static int decode_gain(demuxer_t *demuxer, const char *tag, float *out)
{
char *tag_val = NULL;
float dec_val;
tag_val = mp_tags_get_str(demuxer->metadata, tag);
if (!tag_val)
return -1;
if (decode_float(tag_val, &dec_val)) {
mp_msg(demuxer->log, MSGL_ERR, "Invalid replaygain value\n");
return -1;
}
*out = dec_val;
return 0;
}
static int decode_peak(demuxer_t *demuxer, const char *tag, float *out)
{
char *tag_val = NULL;
float dec_val;
*out = 1.0;
tag_val = mp_tags_get_str(demuxer->metadata, tag);
if (!tag_val)
return 0;
if (decode_float(tag_val, &dec_val))
return 0;
if (dec_val == 0.0)
return 0;
*out = dec_val;
return 0;
}
static void demux_export_replaygain(demuxer_t *demuxer)
{
float tg, tp, ag, ap;
if (!decode_gain(demuxer, "REPLAYGAIN_TRACK_GAIN", &tg) &&
!decode_peak(demuxer, "REPLAYGAIN_TRACK_PEAK", &tp) &&
!decode_gain(demuxer, "REPLAYGAIN_ALBUM_GAIN", &ag) &&
!decode_peak(demuxer, "REPLAYGAIN_ALBUM_PEAK", &ap))
{
struct replaygain_data *rgain = talloc_ptrtype(demuxer, rgain);
rgain->track_gain = tg;
rgain->track_peak = tp;
rgain->album_gain = ag;
rgain->album_peak = ap;
for (int n = 0; n < demuxer->num_streams; n++) {
struct sh_stream *sh = demuxer->streams[n];
if (sh->audio && !sh->audio->replaygain_data)
sh->audio->replaygain_data = rgain;
}
}
}
// Copy all fields from src to dst, depending on event flags.
static void demux_copy(struct demuxer *dst, struct demuxer *src)
{
if (src->events & DEMUX_EVENT_INIT) {
// Note that we do as shallow copies as possible. We expect the date
// that is not-copied (only referenced) to be immutable.
// This implies e.g. that no chapters are added after initialization.
dst->chapters = src->chapters;
dst->num_chapters = src->num_chapters;
dst->editions = src->editions;
dst->num_editions = src->num_editions;
dst->edition = src->edition;
dst->attachments = src->attachments;
dst->num_attachments = src->num_attachments;
dst->matroska_data = src->matroska_data;
dst->file_contents = src->file_contents;
dst->playlist = src->playlist;
dst->seekable = src->seekable;
dst->partially_seekable = src->partially_seekable;
dst->filetype = src->filetype;
dst->ts_resets_possible = src->ts_resets_possible;
dst->rel_seeks = src->rel_seeks;
dst->allow_refresh_seeks = src->allow_refresh_seeks;
dst->start_time = src->start_time;
}
if (src->events & DEMUX_EVENT_STREAMS) {
// The stream structs themselves are immutable.
for (int n = dst->num_streams; n < src->num_streams; n++)
MP_TARRAY_APPEND(dst, dst->streams, dst->num_streams, src->streams[n]);
}
if (src->events & DEMUX_EVENT_METADATA) {
talloc_free(dst->metadata);
dst->metadata = mp_tags_dup(dst, src->metadata);
}
dst->events |= src->events;
src->events = 0;
}
// This is called by demuxer implementations if certain parameters change
// at runtime.
// events is one of DEMUX_EVENT_*
// The code will copy the fields references by the events to the user-thread.
void demux_changed(demuxer_t *demuxer, int events)
{
assert(demuxer == demuxer->in->d_thread); // call from demuxer impl. only
struct demux_internal *in = demuxer->in;
demuxer->events |= events;
update_cache(in);
pthread_mutex_lock(&in->lock);
if (demuxer->events & DEMUX_EVENT_INIT)
demuxer_sort_chapters(demuxer);
if (demuxer->events & (DEMUX_EVENT_METADATA | DEMUX_EVENT_STREAMS))
demux_export_replaygain(demuxer);
demux_copy(in->d_buffer, demuxer);
if (in->wakeup_cb)
in->wakeup_cb(in->wakeup_cb_ctx);
pthread_mutex_unlock(&in->lock);
}
// Called by the user thread (i.e. player) to update metadata and other things
// from the demuxer thread.
void demux_update(demuxer_t *demuxer)
{
assert(demuxer == demuxer->in->d_user);
struct demux_internal *in = demuxer->in;
if (!in->threading)
update_cache(in);
pthread_mutex_lock(&in->lock);
demux_copy(demuxer, in->d_buffer);
if (in->stream_metadata && (demuxer->events & DEMUX_EVENT_METADATA))
mp_tags_merge(demuxer->metadata, in->stream_metadata);
pthread_mutex_unlock(&in->lock);
}
static void demux_init_cache(struct demuxer *demuxer)
{
struct demux_internal *in = demuxer->in;
struct stream *stream = demuxer->stream;
char *base = NULL;
stream_control(stream, STREAM_CTRL_GET_BASE_FILENAME, &base);
in->stream_base_filename = talloc_steal(demuxer, base);
}
static struct demuxer *open_given_type(struct mpv_global *global,
struct mp_log *log,
const struct demuxer_desc *desc,
struct stream *stream,
struct demuxer_params *params,
enum demux_check check)
{
struct demuxer *demuxer = talloc_ptrtype(NULL, demuxer);
*demuxer = (struct demuxer) {
.desc = desc,
.type = desc->type,
.stream = stream,
.seekable = stream->seekable,
.filepos = -1,
.opts = global->opts,
.global = global,
.log = mp_log_new(demuxer, log, desc->name),
.glog = log,
.filename = talloc_strdup(demuxer, stream->url),
.events = DEMUX_EVENT_ALL,
};
demuxer->seekable = stream->seekable;
if (demuxer->stream->uncached_stream &&
!demuxer->stream->uncached_stream->seekable)
demuxer->seekable = false;
struct demux_internal *in = demuxer->in = talloc_ptrtype(demuxer, in);
*in = (struct demux_internal){
.log = demuxer->log,
.d_thread = talloc(demuxer, struct demuxer),
.d_buffer = talloc(demuxer, struct demuxer),
.d_user = demuxer,
.min_secs = demuxer->opts->demuxer_min_secs,
.min_packs = demuxer->opts->demuxer_min_packs,
.min_bytes = demuxer->opts->demuxer_min_bytes,
};
pthread_mutex_init(&in->lock, NULL);
pthread_cond_init(&in->wakeup, NULL);
if (stream->uncached_stream)
in->min_secs = MPMAX(in->min_secs, demuxer->opts->demuxer_min_secs_cache);
*in->d_thread = *demuxer;
*in->d_buffer = *demuxer;
in->d_thread->metadata = talloc_zero(in->d_thread, struct mp_tags);
in->d_user->metadata = talloc_zero(in->d_user, struct mp_tags);
in->d_buffer->metadata = talloc_zero(in->d_buffer, struct mp_tags);
mp_verbose(log, "Trying demuxer: %s (force-level: %s)\n",
desc->name, d_level(check));
in->d_thread->params = params; // temporary during open()
if (stream->seekable) // not for DVD/BD/DVB in particular
stream_seek(stream, 0);
// Peek this much data to avoid that stream_read() run by some demuxers
// or stream filters will flush previous peeked data.
stream_peek(stream, STREAM_BUFFER_SIZE);
int ret = demuxer->desc->open(in->d_thread, check);
if (ret >= 0) {
in->d_thread->params = NULL;
if (in->d_thread->filetype)
mp_verbose(log, "Detected file format: %s (%s)\n",
in->d_thread->filetype, desc->desc);
else
mp_verbose(log, "Detected file format: %s\n", desc->desc);
if (!in->d_thread->seekable)
mp_verbose(log, "Stream is not seekable.\n");
// Pretend we can seek if we can't seek, but there's a cache.
if (!in->d_thread->seekable && stream->uncached_stream) {
mp_verbose(log, "Enabling seeking because stream cache is active.\n");
in->d_thread->seekable = true;
in->d_thread->partially_seekable = true;
}
demux_init_cache(demuxer);
demux_changed(in->d_thread, DEMUX_EVENT_ALL);
demux_update(demuxer);
return demuxer;
}
free_demuxer(demuxer);
return NULL;
}
static const int d_normal[] = {DEMUX_CHECK_NORMAL, DEMUX_CHECK_UNSAFE, -1};
static const int d_request[] = {DEMUX_CHECK_REQUEST, -1};
static const int d_force[] = {DEMUX_CHECK_FORCE, -1};
struct demuxer *demux_open(struct stream *stream, char *force_format,
struct demuxer_params *params,
struct mpv_global *global)
{
const int *check_levels = d_normal;
const struct demuxer_desc *check_desc = NULL;
struct mp_log *log = mp_log_new(NULL, global->log, "!demux");
struct demuxer *demuxer = NULL;
if (!force_format)
force_format = stream->demuxer;
if (force_format && force_format[0]) {
check_levels = d_request;
if (force_format[0] == '+') {
force_format += 1;
check_levels = d_force;
}
for (int n = 0; demuxer_list[n]; n++) {
if (strcmp(demuxer_list[n]->name, force_format) == 0)
check_desc = demuxer_list[n];
}
if (!check_desc) {
mp_err(log, "Demuxer %s does not exist.\n", force_format);
goto done;
}
}
// Test demuxers from first to last, one pass for each check_levels[] entry
for (int pass = 0; check_levels[pass] != -1; pass++) {
enum demux_check level = check_levels[pass];
for (int n = 0; demuxer_list[n]; n++) {
const struct demuxer_desc *desc = demuxer_list[n];
if (!check_desc || desc == check_desc) {
demuxer = open_given_type(global, log, desc, stream, params, level);
if (demuxer) {
talloc_steal(demuxer, log);
log = NULL;
goto done;
}
}
}
}
done:
talloc_free(log);
return demuxer;
}
static void flush_locked(demuxer_t *demuxer)
{
for (int n = 0; n < demuxer->num_streams; n++)
ds_flush(demuxer->streams[n]->ds);
demuxer->in->warned_queue_overflow = false;
demuxer->in->eof = false;
demuxer->in->last_eof = false;
demuxer->in->idle = true;
demuxer->filepos = -1; // implicitly synchronized
}
// clear the packet queues
void demux_flush(demuxer_t *demuxer)
{
pthread_mutex_lock(&demuxer->in->lock);
flush_locked(demuxer);
pthread_mutex_unlock(&demuxer->in->lock);
}
int demux_seek(demuxer_t *demuxer, double rel_seek_secs, int flags)
{
struct demux_internal *in = demuxer->in;
assert(demuxer == in->d_user);
if (!demuxer->seekable) {
MP_WARN(demuxer, "Cannot seek in this file.\n");
return 0;
}
if ((flags & SEEK_FACTOR) && !(flags & SEEK_ABSOLUTE)) {
MP_WARN(demuxer, "Invalid seek flags.\n");
return 0;
}
if (rel_seek_secs == MP_NOPTS_VALUE && (flags & SEEK_ABSOLUTE))
return 0;
if (!(flags & (SEEK_BACKWARD | SEEK_FORWARD))) {
if (flags & SEEK_ABSOLUTE || rel_seek_secs < 0) {
flags |= SEEK_BACKWARD;
} else {
flags |= SEEK_FORWARD;
}
}
pthread_mutex_lock(&in->lock);
flush_locked(demuxer);
in->seeking = true;
in->seek_flags = flags;
in->seek_pts = rel_seek_secs;
if (!in->threading)
execute_seek(in);
pthread_cond_signal(&in->wakeup);
pthread_mutex_unlock(&in->lock);
return 1;
}
// Enable doing a "refresh seek" on the next stream switch.
// Note that this by design does not disable ongoing refresh seeks, and
// does not affect previous stream switch commands (even if they were
// asynchronous).
void demux_set_enable_refresh_seeks(struct demuxer *demuxer, bool enabled)
{
struct demux_internal *in = demuxer->in;
pthread_mutex_lock(&in->lock);
in->refresh_seeks_enabled = enabled;
pthread_mutex_unlock(&in->lock);
}
struct sh_stream *demuxer_stream_by_demuxer_id(struct demuxer *d,
enum stream_type t, int id)
{
for (int n = 0; n < d->num_streams; n++) {
struct sh_stream *s = d->streams[n];
if (s->type == t && s->demuxer_id == id)
return d->streams[n];
}
return NULL;
}
void demuxer_switch_track(struct demuxer *demuxer, enum stream_type type,
struct sh_stream *stream)
{
assert(!stream || stream->type == type);
for (int n = 0; n < demuxer->num_streams; n++) {
struct sh_stream *cur = demuxer->streams[n];
if (cur->type == type)
demuxer_select_track(demuxer, cur, cur == stream);
}
}
void demuxer_select_track(struct demuxer *demuxer, struct sh_stream *stream,
bool selected)
{
struct demux_internal *in = demuxer->in;
pthread_mutex_lock(&in->lock);
bool update = false;
// don't flush buffers if stream is already selected / unselected
if (stream->ds->selected != selected) {
stream->ds->selected = selected;
stream->ds->active = false;
ds_flush(stream->ds);
if (selected && in->refresh_seeks_enabled && in->threading)
in->start_refresh_seek = true;
update = true;
}
pthread_mutex_unlock(&in->lock);
if (update)
demux_control(demuxer, DEMUXER_CTRL_SWITCHED_TRACKS, NULL);
}
void demux_set_stream_autoselect(struct demuxer *demuxer, bool autoselect)
{
assert(!demuxer->in->threading); // laziness
demuxer->in->autoselect = autoselect;
}
bool demux_stream_is_selected(struct sh_stream *stream)
{
if (!stream)
return false;
bool r = false;
pthread_mutex_lock(&stream->ds->in->lock);
r = stream->ds->selected;
pthread_mutex_unlock(&stream->ds->in->lock);
return r;
}
int demuxer_add_attachment(demuxer_t *demuxer, struct bstr name,
struct bstr type, struct bstr data)
{
if (!(demuxer->num_attachments % 32))
demuxer->attachments = talloc_realloc(demuxer, demuxer->attachments,
struct demux_attachment,
demuxer->num_attachments + 32);
struct demux_attachment *att =
demuxer->attachments + demuxer->num_attachments;
att->name = talloc_strndup(demuxer->attachments, name.start, name.len);
att->type = talloc_strndup(demuxer->attachments, type.start, type.len);
att->data = talloc_size(demuxer->attachments, data.len);
memcpy(att->data, data.start, data.len);
att->data_size = data.len;
return demuxer->num_attachments++;
}
static int chapter_compare(const void *p1, const void *p2)
{
struct demux_chapter *c1 = (void *)p1;
struct demux_chapter *c2 = (void *)p2;
if (c1->pts > c2->pts)
return 1;
else if (c1->pts < c2->pts)
return -1;
return c1->original_index > c2->original_index ? 1 :-1; // never equal
}
static void demuxer_sort_chapters(demuxer_t *demuxer)
{
qsort(demuxer->chapters, demuxer->num_chapters,
sizeof(struct demux_chapter), chapter_compare);
}
int demuxer_add_chapter(demuxer_t *demuxer, struct bstr name,
double pts, uint64_t demuxer_id)
{
struct demux_chapter new = {
.original_index = demuxer->num_chapters,
.pts = pts,
.name = name.len ? bstrdup0(demuxer, name) : NULL,
.metadata = talloc_zero(demuxer, struct mp_tags),
.demuxer_id = demuxer_id,
};
mp_tags_set_bstr(new.metadata, bstr0("TITLE"), name);
MP_TARRAY_APPEND(demuxer, demuxer->chapters, demuxer->num_chapters, new);
return demuxer->num_chapters - 1;
}
double demuxer_get_time_length(struct demuxer *demuxer)
{
double len;
if (demux_control(demuxer, DEMUXER_CTRL_GET_TIME_LENGTH, &len) > 0)
return len;
return -1;
}
// must be called not locked
static void update_cache(struct demux_internal *in)
{
struct demuxer *demuxer = in->d_thread;
struct stream *stream = demuxer->stream;
// Don't lock while querying the stream.
double time_length = -1;
struct mp_tags *stream_metadata = NULL;
int64_t stream_size = -1;
int64_t stream_cache_size = -1;
int64_t stream_cache_fill = -1;
int stream_cache_idle = -1;
struct mp_nav_event *nav_event = NULL;
pthread_mutex_lock(&in->lock);
bool need_nav_event = !in->nav_event;;
pthread_mutex_unlock(&in->lock);
if (demuxer->desc->control) {
demuxer->desc->control(demuxer, DEMUXER_CTRL_GET_TIME_LENGTH,
&time_length);
if (need_nav_event)
demuxer->desc->control(demuxer, DEMUXER_CTRL_GET_NAV_EVENT, &nav_event);
}
stream_control(stream, STREAM_CTRL_GET_METADATA, &stream_metadata);
stream_control(stream, STREAM_CTRL_GET_SIZE, &stream_size);
stream_control(stream, STREAM_CTRL_GET_CACHE_SIZE, &stream_cache_size);
stream_control(stream, STREAM_CTRL_GET_CACHE_FILL, &stream_cache_fill);
stream_control(stream, STREAM_CTRL_GET_CACHE_IDLE, &stream_cache_idle);
pthread_mutex_lock(&in->lock);
in->time_length = time_length;
in->stream_size = stream_size;
in->stream_cache_size = stream_cache_size;
in->stream_cache_fill = stream_cache_fill;
in->stream_cache_idle = stream_cache_idle;
if (stream_metadata) {
talloc_free(in->stream_metadata);
in->stream_metadata = talloc_steal(in, stream_metadata);
in->d_buffer->events |= DEMUX_EVENT_METADATA;
}
in->nav_event = nav_event ? nav_event : in->nav_event;
pthread_mutex_unlock(&in->lock);
}
// must be called locked
static int cached_stream_control(struct demux_internal *in, int cmd, void *arg)
{
// If the cache is active, wake up the thread to possibly update cache state.
if (in->stream_cache_size >= 0) {
in->force_cache_update = true;
pthread_cond_signal(&in->wakeup);
}
switch (cmd) {
case STREAM_CTRL_GET_CACHE_SIZE:
if (in->stream_cache_size < 0)
return STREAM_UNSUPPORTED;
*(int64_t *)arg = in->stream_cache_size;
return STREAM_OK;
case STREAM_CTRL_GET_CACHE_FILL:
if (in->stream_cache_fill < 0)
return STREAM_UNSUPPORTED;
*(int64_t *)arg = in->stream_cache_fill;
return STREAM_OK;
case STREAM_CTRL_GET_CACHE_IDLE:
if (in->stream_cache_idle < 0)
return STREAM_UNSUPPORTED;
*(int *)arg = in->stream_cache_idle;
return STREAM_OK;
case STREAM_CTRL_GET_SIZE:
if (in->stream_size < 0)
return STREAM_UNSUPPORTED;
*(int64_t *)arg = in->stream_size;
return STREAM_OK;
case STREAM_CTRL_GET_BASE_FILENAME:
if (!in->stream_base_filename)
return STREAM_UNSUPPORTED;
*(char **)arg = talloc_strdup(NULL, in->stream_base_filename);
return STREAM_OK;
}
return STREAM_ERROR;
}
// must be called locked
static int cached_demux_control(struct demux_internal *in, int cmd, void *arg)
{
switch (cmd) {
case DEMUXER_CTRL_GET_TIME_LENGTH:
if (in->time_length < 0)
return DEMUXER_CTRL_NOTIMPL;
*(double *)arg = in->time_length;
return DEMUXER_CTRL_OK;
case DEMUXER_CTRL_STREAM_CTRL: {
struct demux_ctrl_stream_ctrl *c = arg;
int r = cached_stream_control(in, c->ctrl, c->arg);
if (r == STREAM_ERROR)
break;
c->res = r;
return DEMUXER_CTRL_OK;
}
case DEMUXER_CTRL_SWITCHED_TRACKS:
in->tracks_switched = true;
pthread_cond_signal(&in->wakeup);
return DEMUXER_CTRL_OK;
case DEMUXER_CTRL_GET_BITRATE_STATS: {
double *rates = arg;
for (int n = 0; n < STREAM_TYPE_COUNT; n++)
rates[n] = 0;
for (int n = 0; n < in->d_user->num_streams; n++) {
struct demux_stream *ds = in->d_user->streams[n]->ds;
rates[ds->type] += MPMAX(0, ds->bitrate);
}
return DEMUXER_CTRL_OK;
}
case DEMUXER_CTRL_GET_READER_STATE: {
struct demux_ctrl_reader_state *r = arg;
*r = (struct demux_ctrl_reader_state){
.eof = in->last_eof,
.ts_range = {MP_NOPTS_VALUE, MP_NOPTS_VALUE},
.ts_duration = -1,
};
int num_packets = 0;
for (int n = 0; n < in->d_user->num_streams; n++) {
struct demux_stream *ds = in->d_user->streams[n]->ds;
if (ds->active) {
r->underrun |= !ds->head && !ds->eof;
if (!ds->eof) {
r->ts_range[0] = MP_PTS_MAX(r->ts_range[0], ds->base_ts);
r->ts_range[1] = MP_PTS_MIN(r->ts_range[1], ds->last_ts);
}
num_packets += ds->packs;
}
}
r->idle = (in->idle && !r->underrun) || r->eof;
r->underrun &= !r->idle;
if (r->ts_range[0] != MP_NOPTS_VALUE && r->ts_range[1] != MP_NOPTS_VALUE)
r->ts_duration = MPMAX(0, r->ts_range[1] - r->ts_range[0]);
if (!num_packets || in->seeking)
r->ts_duration = 0;
return DEMUXER_CTRL_OK;
}
case DEMUXER_CTRL_GET_NAV_EVENT:
if (!in->nav_event)
return DEMUXER_CTRL_NOTIMPL;
*(struct mp_nav_event **)arg = in->nav_event;
in->nav_event = NULL;
return DEMUXER_CTRL_OK;
}
return DEMUXER_CTRL_DONTKNOW;
}
int demux_control(demuxer_t *demuxer, int cmd, void *arg)
{
struct demux_internal *in = demuxer->in;
if (in->threading) {
pthread_mutex_lock(&in->lock);
int cr = cached_demux_control(in, cmd, arg);
pthread_mutex_unlock(&in->lock);
if (cr != DEMUXER_CTRL_DONTKNOW)
return cr;
}
int r = DEMUXER_CTRL_NOTIMPL;
demux_pause(demuxer);
if (cmd == DEMUXER_CTRL_STREAM_CTRL) {
struct demux_ctrl_stream_ctrl *c = arg;
if (in->threading)
MP_VERBOSE(demuxer, "blocking for STREAM_CTRL %d\n", c->ctrl);
c->res = stream_control(demuxer->stream, c->ctrl, c->arg);
if (c->res != STREAM_UNSUPPORTED)
r = DEMUXER_CTRL_OK;
}
if (r != DEMUXER_CTRL_OK) {
if (in->threading)
MP_VERBOSE(demuxer, "blocking for DEMUXER_CTRL %d\n", cmd);
if (demuxer->desc->control)
r = demuxer->desc->control(demuxer->in->d_thread, cmd, arg);
}
demux_unpause(demuxer);
return r;
}
int demux_stream_control(demuxer_t *demuxer, int ctrl, void *arg)
{
struct demux_ctrl_stream_ctrl c = {ctrl, arg, STREAM_UNSUPPORTED};
demux_control(demuxer, DEMUXER_CTRL_STREAM_CTRL, &c);
return c.res;
}
// Make the demuxer thread stop doing anything.
// demux_unpause() wakes up the thread again.
// Can be nested with other calls, but trying to read packets may deadlock.
void demux_pause(demuxer_t *demuxer)
{
struct demux_internal *in = demuxer->in;
assert(demuxer == in->d_user);
if (!in->threading)
return;
MP_VERBOSE(in, "pause demux thread\n");
pthread_mutex_lock(&in->lock);
in->thread_request_pause++;
pthread_cond_signal(&in->wakeup);
while (!in->thread_paused)
pthread_cond_wait(&in->wakeup, &in->lock);
pthread_mutex_unlock(&in->lock);
}
void demux_unpause(demuxer_t *demuxer)
{
struct demux_internal *in = demuxer->in;
assert(demuxer == in->d_user);
if (!in->threading)
return;
pthread_mutex_lock(&in->lock);
assert(in->thread_request_pause > 0);
in->thread_request_pause--;
pthread_cond_signal(&in->wakeup);
pthread_mutex_unlock(&in->lock);
}
struct demux_chapter *demux_copy_chapter_data(struct demux_chapter *c, int num)
{
struct demux_chapter *new = talloc_array(NULL, struct demux_chapter, num);
for (int n = 0; n < num; n++) {
new[n] = c[n];
new[n].name = talloc_strdup(new, new[n].name);
new[n].metadata = mp_tags_dup(new, new[n].metadata);
}
return new;
}