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mpv/demux/demux.h
wm4 bc97d60542 demux: close underlying stream if it's fully read anyway
This is for text subtitles. libavformat currently always reads text
subtitles completely on init. This means the underlying stream is
useless and will consume resources for various reasons (network
connection, file handles, cache memory).

Take care of this by closing the underlying stream if we think the
demuxer has read everything. Since libavformat doesn't export whether it
did (or whether it may access the stream again in the future), we rely
on a whitelist. Also, instead of setting the stream to NULL or so, set
it to an empty dummy stream. This way we don't have to litter the code
with NULL checks.

demux_lavf.c needs extra changes, because it tries to do clever things
for the sake of subtitle charset conversion.

The main reason we keep the demuxer etc. open is because we fell for
libavformat being so generic, and we tried to remove corresponding
special-cases in the higher-level player code. Some of this is forced
due to ass/srt mkv/mp4 demuxing being very similar to external text
files. In the future it might be better to do this in a more
straight-forward way, such as reading text subtitles into libass and
then discarding the demuxer entirely, but for aforementioned reasons
this could be more of a mess than the solution introduced by this
commit.

Probably fixes #3456.
2016-08-26 13:34:52 +02:00

305 lines
9.8 KiB
C

/*
* This file is part of mpv.
*
* mpv 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.
*
* mpv 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 mpv. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef MPLAYER_DEMUXER_H
#define MPLAYER_DEMUXER_H
#include <sys/types.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <stdbool.h>
#include "misc/bstr.h"
#include "common/common.h"
#include "common/tags.h"
#include "packet.h"
#include "stheader.h"
// DEMUXER control commands/answers
#define DEMUXER_CTRL_NOTIMPL -1
#define DEMUXER_CTRL_DONTKNOW 0
#define DEMUXER_CTRL_OK 1
enum demux_ctrl {
DEMUXER_CTRL_SWITCHED_TRACKS = 1,
DEMUXER_CTRL_GET_TIME_LENGTH,
DEMUXER_CTRL_RESYNC,
DEMUXER_CTRL_IDENTIFY_PROGRAM,
DEMUXER_CTRL_STREAM_CTRL,
DEMUXER_CTRL_GET_READER_STATE,
DEMUXER_CTRL_GET_BITRATE_STATS, // double[STREAM_TYPE_COUNT]
DEMUXER_CTRL_REPLACE_STREAM,
};
struct demux_ctrl_reader_state {
bool eof, underrun, idle;
double ts_range[2]; // start, end
double ts_duration;
};
struct demux_ctrl_stream_ctrl {
int ctrl;
void *arg;
int res;
};
#define SEEK_FACTOR (1 << 1) // argument is in range [0,1]
#define SEEK_FORWARD (1 << 2) // prefer later time if not exact
#define SEEK_BACKWARD (1 << 3) // prefer earlier time if not exact
#define SEEK_HR (1 << 5) // hr-seek (this is a weak hint only)
// Strictness of the demuxer open format check.
// demux.c will try by default: NORMAL, UNSAFE (in this order)
// Using "-demuxer format" will try REQUEST
// Using "-demuxer +format" will try FORCE
// REQUEST can be used as special value for raw demuxers which have no file
// header check; then they should fail if check!=FORCE && check!=REQUEST.
//
// In general, the list is sorted from weakest check to normal check.
// You can use relation operators to compare the check level.
enum demux_check {
DEMUX_CHECK_FORCE, // force format if possible
DEMUX_CHECK_UNSAFE, // risky/fuzzy detection
DEMUX_CHECK_REQUEST,// requested by user or stream implementation
DEMUX_CHECK_NORMAL, // normal, safe detection
};
enum demux_event {
DEMUX_EVENT_INIT = 1 << 0, // complete (re-)initialization
DEMUX_EVENT_STREAMS = 1 << 1, // a stream was added
DEMUX_EVENT_METADATA = 1 << 2, // metadata or stream_metadata changed
DEMUX_EVENT_ALL = 0xFFFF,
};
struct demuxer;
struct timeline;
/**
* Demuxer description structure
*/
typedef struct demuxer_desc {
const char *name; // Demuxer name, used with -demuxer switch
const char *desc; // Displayed to user
// Return 0 on success, otherwise -1
int (*open)(struct demuxer *demuxer, enum demux_check check);
// The following functions are all optional
int (*fill_buffer)(struct demuxer *demuxer); // 0 on EOF, otherwise 1
void (*close)(struct demuxer *demuxer);
void (*seek)(struct demuxer *demuxer, double rel_seek_secs, int flags);
int (*control)(struct demuxer *demuxer, int cmd, void *arg);
// See timeline.c
void (*load_timeline)(struct timeline *tl);
} demuxer_desc_t;
typedef struct demux_chapter
{
int original_index;
double pts;
struct mp_tags *metadata;
uint64_t demuxer_id; // for mapping to internal demuxer data structures
} demux_chapter_t;
struct demux_edition {
uint64_t demuxer_id;
bool default_edition;
struct mp_tags *metadata;
};
struct matroska_segment_uid {
unsigned char segment[16];
uint64_t edition;
};
struct matroska_data {
struct matroska_segment_uid uid;
// Ordered chapter information if any
struct matroska_chapter {
uint64_t start;
uint64_t end;
bool has_segment_uid;
struct matroska_segment_uid uid;
char *name;
} *ordered_chapters;
int num_ordered_chapters;
};
struct replaygain_data {
float track_gain;
float track_peak;
float album_gain;
float album_peak;
};
typedef struct demux_attachment
{
char *name;
char *type;
void *data;
unsigned int data_size;
} demux_attachment_t;
struct demuxer_params {
char *force_format;
int matroska_num_wanted_uids;
struct matroska_segment_uid *matroska_wanted_uids;
int matroska_wanted_segment;
bool *matroska_was_valid;
struct timeline *timeline;
// -- demux_open_url() only
int stream_flags;
bool allow_capture;
bool disable_cache;
// result
bool demuxer_failed;
};
typedef struct demuxer {
const demuxer_desc_t *desc; ///< Demuxer description structure
const char *filetype; // format name when not identified by demuxer (libavformat)
int64_t filepos; // input stream current pos.
char *filename; // same as stream->url
bool seekable;
bool partially_seekable; // true if _maybe_ seekable; implies seekable=true
double start_time;
// File format allows PTS resets (even if the current file is without)
bool ts_resets_possible;
// The file data was fully read, and there is no need to keep the stream
// open, keep the cache active, or to run the demuxer thread. Generating
// packets is not slow either (unlike e.g. libavdevice pseudo-demuxers).
// Typical examples: text subtitles, playlists
bool fully_read;
bool is_network; // opened directly from a network stream
// Bitmask of DEMUX_EVENT_*
int events;
struct demux_edition *editions;
int num_editions;
int edition;
struct demux_chapter *chapters;
int num_chapters;
struct demux_attachment *attachments;
int num_attachments;
struct matroska_data matroska_data;
// If the file is a playlist file
struct playlist *playlist;
struct mp_tags *metadata;
void *priv; // demuxer-specific internal data
struct MPOpts *opts;
struct mpv_global *global;
struct mp_log *log, *glog;
struct demuxer_params *params;
// internal to demux.c
struct demux_internal *in;
struct mp_tags **update_stream_tags;
int num_update_stream_tags;
// Since the demuxer can run in its own thread, and the stream is not
// thread-safe, only the demuxer is allowed to access the stream directly.
// You can freely use demux_stream_control() to send STREAM_CTRLs, or use
// demux_pause() to get exclusive access to the stream.
// Also note that the stream can get replaced if fully_read is set.
struct stream *stream;
} demuxer_t;
typedef struct {
int progid; //program id
int aid, vid, sid; //audio, video and subtitle id
} demux_program_t;
void free_demuxer(struct demuxer *demuxer);
void free_demuxer_and_stream(struct demuxer *demuxer);
void demux_add_packet(struct sh_stream *stream, demux_packet_t *dp);
void demuxer_feed_caption(struct sh_stream *stream, demux_packet_t *dp);
struct demux_packet *demux_read_packet(struct sh_stream *sh);
int demux_read_packet_async(struct sh_stream *sh, struct demux_packet **out_pkt);
bool demux_stream_is_selected(struct sh_stream *stream);
bool demux_has_packet(struct sh_stream *sh);
struct demux_packet *demux_read_any_packet(struct demuxer *demuxer);
struct sh_stream *demux_get_stream(struct demuxer *demuxer, int index);
int demux_get_num_stream(struct demuxer *demuxer);
struct sh_stream *demux_alloc_sh_stream(enum stream_type type);
void demux_add_sh_stream(struct demuxer *demuxer, struct sh_stream *sh);
struct demuxer *demux_open(struct stream *stream, struct demuxer_params *params,
struct mpv_global *global);
struct mp_cancel;
struct demuxer *demux_open_url(const char *url,
struct demuxer_params *params,
struct mp_cancel *cancel,
struct mpv_global *global);
void demux_start_thread(struct demuxer *demuxer);
void demux_stop_thread(struct demuxer *demuxer);
void demux_set_wakeup_cb(struct demuxer *demuxer, void (*cb)(void *ctx), void *ctx);
bool demux_cancel_test(struct demuxer *demuxer);
void demux_flush(struct demuxer *demuxer);
int demux_seek(struct demuxer *demuxer, double rel_seek_secs, int flags);
void demux_set_ts_offset(struct demuxer *demuxer, double offset);
int demux_control(struct demuxer *demuxer, int cmd, void *arg);
void demuxer_select_track(struct demuxer *demuxer, struct sh_stream *stream,
double ref_pts, bool selected);
void demux_set_stream_autoselect(struct demuxer *demuxer, bool autoselect);
void demuxer_help(struct mp_log *log);
int demuxer_add_attachment(struct demuxer *demuxer, char *name,
char *type, void *data, size_t data_size);
int demuxer_add_chapter(demuxer_t *demuxer, char *name,
double pts, uint64_t demuxer_id);
void demux_set_stream_tags(struct demuxer *demuxer, struct sh_stream *sh,
struct mp_tags *tags);
double demuxer_get_time_length(struct demuxer *demuxer);
int demux_stream_control(demuxer_t *demuxer, int ctrl, void *arg);
void demux_run_on_thread(struct demuxer *demuxer, void (*fn)(void *), void *ctx);
void demux_changed(demuxer_t *demuxer, int events);
void demux_update(demuxer_t *demuxer);
struct sh_stream *demuxer_stream_by_demuxer_id(struct demuxer *d,
enum stream_type t, int id);
struct demux_chapter *demux_copy_chapter_data(struct demux_chapter *c, int num);
bool demux_matroska_uid_cmp(struct matroska_segment_uid *a,
struct matroska_segment_uid *b);
const char *stream_type_name(enum stream_type type);
#endif /* MPLAYER_DEMUXER_H */