lavf: remove unused code

Nothing uses it, and it provides no public API.

Archeological finds:

Commit 101036adb9 added the API.
Commit a8dd8dc6e9 made mpegts.c use it.
Commit af8aae3fa3 disabled it by default in mpegts.c.
Commit ae2bb52cd2 removed all uses of this from mpegts.c.

Signed-off-by: Anton Khirnov <anton@khirnov.net>

4 files changed, 0 insertions, 632 deletions

diff --git a/libavformat/Makefile b/libavformat/Makefile
index bdd0e9ebdc..ea91a6cfac 100644
--- a/libavformat/Makefile
+++ b/libavformat/Makefile
@@ -19,7 +19,6 @@ OBJS = allformats.o         \
        os_support.o         \
        riff.o               \
        sdp.o                \
-       seek.o               \
        url.o                \
        utils.o              \
 
diff --git a/libavformat/mpegts.c b/libavformat/mpegts.c
index cb548d2bd0..ce13a0832e 100644
--- a/libavformat/mpegts.c
+++ b/libavformat/mpegts.c
@@ -33,7 +33,6 @@
 #include "mpegts.h"
 #include "internal.h"
 #include "avio_internal.h"
-#include "seek.h"
 #include "mpeg.h"
 #include "isom.h"
 
diff --git a/libavformat/seek.c b/libavformat/seek.c
deleted file mode 100644
index 9be8db9784..0000000000
--- a/libavformat/seek.c
+++ /dev/null
@@ -1,508 +0,0 @@
-/*
- * seek utility functions for use within format handlers
- *
- * Copyright (c) 2009 Ivan Schreter
- *
- * This file is part of Libav.
- *
- * Libav 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.
- *
- * Libav 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 Libav; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-#include <stdint.h>
-
-#include "seek.h"
-#include "libavutil/mathematics.h"
-#include "libavutil/mem.h"
-#include "internal.h"
-
-// NOTE: implementation should be moved here in another patch, to keep patches
-// separated.
-
-/**
- * helper structure describing keyframe search state of one stream
- */
-typedef struct {
-    int64_t     pos_lo;      ///< position of the frame with low timestamp in file or INT64_MAX if not found (yet)
-    int64_t     ts_lo;       ///< frame presentation timestamp or same as pos_lo for byte seeking
-
-    int64_t     pos_hi;      ///< position of the frame with high timestamp in file or INT64_MAX if not found (yet)
-    int64_t     ts_hi;       ///< frame presentation timestamp or same as pos_hi for byte seeking
-
-    int64_t     last_pos;    ///< last known position of a frame, for multi-frame packets
-
-    int64_t     term_ts;     ///< termination timestamp (which TS we already read)
-    AVRational  term_ts_tb;  ///< timebase for term_ts
-    int64_t     first_ts;    ///< first packet timestamp in this iteration (to fill term_ts later)
-    AVRational  first_ts_tb; ///< timebase for first_ts
-
-    int         terminated;  ///< termination flag for the current iteration
-} AVSyncPoint;
-
-/**
- * Compute a distance between timestamps.
- *
- * Distances are only comparable, if same time bases are used for computing
- * distances.
- *
- * @param ts_hi high timestamp
- * @param tb_hi high timestamp time base
- * @param ts_lo low timestamp
- * @param tb_lo low timestamp time base
- * @return representation of distance between high and low timestamps
- */
-static int64_t ts_distance(int64_t ts_hi,
-                           AVRational tb_hi,
-                           int64_t ts_lo,
-                           AVRational tb_lo)
-{
-    int64_t hi, lo;
-
-    hi = ts_hi * tb_hi.num * tb_lo.den;
-    lo = ts_lo * tb_lo.num * tb_hi.den;
-
-    return hi - lo;
-}
-
-/**
- * Partial search for keyframes in multiple streams.
- *
- * This routine searches in each stream for the next lower and the next higher
- * timestamp compared to the given target timestamp. The search starts at the current
- * file position and ends at the file position, where all streams have already been
- * examined (or when all higher key frames are found in the first iteration).
- *
- * This routine is called iteratively with an exponential backoff to find the lower
- * timestamp.
- *
- * @param s                 format context
- * @param timestamp         target timestamp (or position, if AVSEEK_FLAG_BYTE)
- * @param timebase          time base for timestamps
- * @param flags             seeking flags
- * @param sync              array with information per stream
- * @param keyframes_to_find count of keyframes to find in total
- * @param found_lo          ptr to the count of already found low timestamp keyframes
- * @param found_hi          ptr to the count of already found high timestamp keyframes
- * @param first_iter        flag for first iteration
- */
-static void search_hi_lo_keyframes(AVFormatContext *s,
-                                   int64_t timestamp,
-                                   AVRational timebase,
-                                   int flags,
-                                   AVSyncPoint *sync,
-                                   int keyframes_to_find,
-                                   int *found_lo,
-                                   int *found_hi,
-                                   int first_iter)
-{
-    AVPacket pkt;
-    AVSyncPoint *sp;
-    AVStream *st;
-    int idx;
-    int flg;
-    int terminated_count = 0;
-    int64_t pos;
-    int64_t pts, dts;   // PTS/DTS from stream
-    int64_t ts;         // PTS in stream-local time base or position for byte seeking
-    AVRational ts_tb;   // Time base of the stream or 1:1 for byte seeking
-
-    for (;;) {
-        if (av_read_frame(s, &pkt) < 0) {
-            // EOF or error, make sure high flags are set
-            for (idx = 0; idx < s->nb_streams; ++idx) {
-                if (s->streams[idx]->discard < AVDISCARD_ALL) {
-                    sp = &sync[idx];
-                    if (sp->pos_hi == INT64_MAX) {
-                        // no high frame exists for this stream
-                        (*found_hi)++;
-                        sp->ts_hi  = INT64_MAX;
-                        sp->pos_hi = INT64_MAX - 1;
-                    }
-                }
-            }
-            break;
-        }
-
-        idx = pkt.stream_index;
-        st = s->streams[idx];
-        if (st->discard >= AVDISCARD_ALL)
-            // this stream is not active, skip packet
-            continue;
-
-        sp = &sync[idx];
-
-        flg = pkt.flags;
-        pos = pkt.pos;
-        pts = pkt.pts;
-        dts = pkt.dts;
-        if (pts == AV_NOPTS_VALUE)
-            // some formats don't provide PTS, only DTS
-            pts = dts;
-
-        av_free_packet(&pkt);
-
-        // Multi-frame packets only return position for the very first frame.
-        // Other frames are read with position == -1. Therefore, we note down
-        // last known position of a frame and use it if a frame without
-        // position arrives. In this way, it's possible to seek to proper
-        // position. Additionally, for parsers not providing position at all,
-        // an approximation will be used (starting position of this iteration).
-        if (pos < 0)
-            pos = sp->last_pos;
-        else
-            sp->last_pos = pos;
-
-        // Evaluate key frames with known TS (or any frames, if AVSEEK_FLAG_ANY set).
-        if (pts != AV_NOPTS_VALUE &&
-            ((flg & AV_PKT_FLAG_KEY) || (flags & AVSEEK_FLAG_ANY))) {
-            if (flags & AVSEEK_FLAG_BYTE) {
-                // for byte seeking, use position as timestamp
-                ts        = pos;
-                ts_tb.num = 1;
-                ts_tb.den = 1;
-            } else {
-                // otherwise, get stream time_base
-                ts    = pts;
-                ts_tb = st->time_base;
-            }
-
-            if (sp->first_ts == AV_NOPTS_VALUE) {
-                // Note down termination timestamp for the next iteration - when
-                // we encounter a packet with the same timestamp, we will ignore
-                // any further packets for this stream in next iteration (as they
-                // are already evaluated).
-                sp->first_ts    = ts;
-                sp->first_ts_tb = ts_tb;
-            }
-
-            if (sp->term_ts != AV_NOPTS_VALUE &&
-                av_compare_ts(ts, ts_tb, sp->term_ts, sp->term_ts_tb) > 0) {
-                // past the end position from last iteration, ignore packet
-                if (!sp->terminated) {
-                    sp->terminated = 1;
-                    ++terminated_count;
-                    if (sp->pos_hi == INT64_MAX) {
-                        // no high frame exists for this stream
-                        (*found_hi)++;
-                        sp->ts_hi  = INT64_MAX;
-                        sp->pos_hi = INT64_MAX - 1;
-                    }
-                    if (terminated_count == keyframes_to_find)
-                        break;  // all terminated, iteration done
-                }
-                continue;
-            }
-
-            if (av_compare_ts(ts, ts_tb, timestamp, timebase) <= 0) {
-                // keyframe found before target timestamp
-                if (sp->pos_lo == INT64_MAX) {
-                    // found first keyframe lower than target timestamp
-                    (*found_lo)++;
-                    sp->ts_lo  = ts;
-                    sp->pos_lo = pos;
-                } else if (sp->ts_lo < ts) {
-                    // found a better match (closer to target timestamp)
-                    sp->ts_lo  = ts;
-                    sp->pos_lo = pos;
-                }
-            }
-            if (av_compare_ts(ts, ts_tb, timestamp, timebase) >= 0) {
-                // keyframe found after target timestamp
-                if (sp->pos_hi == INT64_MAX) {
-                    // found first keyframe higher than target timestamp
-                    (*found_hi)++;
-                    sp->ts_hi  = ts;
-                    sp->pos_hi = pos;
-                    if (*found_hi >= keyframes_to_find && first_iter) {
-                        // We found high frame for all. They may get updated
-                        // to TS closer to target TS in later iterations (which
-                        // will stop at start position of previous iteration).
-                        break;
-                    }
-                } else if (sp->ts_hi > ts) {
-                    // found a better match (actually, shouldn't happen)
-                    sp->ts_hi  = ts;
-                    sp->pos_hi = pos;
-                }
-            }
-        }
-    }
-
-    // Clean up the parser.
-    ff_read_frame_flush(s);
-}
-
-int64_t ff_gen_syncpoint_search(AVFormatContext *s,
-                                int stream_index,
-                                int64_t pos,
-                                int64_t ts_min,
-                                int64_t ts,
-                                int64_t ts_max,
-                                int flags)
-{
-    AVSyncPoint *sync, *sp;
-    AVStream *st;
-    int i;
-    int keyframes_to_find = 0;
-    int64_t curpos;
-    int64_t step;
-    int found_lo = 0, found_hi = 0;
-    int64_t min_distance, distance;
-    int64_t min_pos = 0;
-    int first_iter = 1;
-    AVRational time_base;
-
-    if (flags & AVSEEK_FLAG_BYTE) {
-        // for byte seeking, we have exact 1:1 "timestamps" - positions
-        time_base.num = 1;
-        time_base.den = 1;
-    } else {
-        if (stream_index >= 0) {
-            // we have a reference stream, which time base we use
-            st = s->streams[stream_index];
-            time_base = st->time_base;
-        } else {
-            // no reference stream, use AV_TIME_BASE as reference time base
-            time_base.num = 1;
-            time_base.den = AV_TIME_BASE;
-        }
-    }
-
-    // Initialize syncpoint structures for each stream.
-    sync = av_malloc(s->nb_streams * sizeof(AVSyncPoint));
-    if (!sync)
-        // cannot allocate helper structure
-        return -1;
-
-    for (i = 0; i < s->nb_streams; ++i) {
-        st = s->streams[i];
-        sp = &sync[i];
-
-        sp->pos_lo     = INT64_MAX;
-        sp->ts_lo      = INT64_MAX;
-        sp->pos_hi     = INT64_MAX;
-        sp->ts_hi      = INT64_MAX;
-        sp->terminated = 0;
-        sp->first_ts   = AV_NOPTS_VALUE;
-        sp->term_ts    = ts_max;
-        sp->term_ts_tb = time_base;
-        sp->last_pos   = pos;
-
-        st->cur_dts    = AV_NOPTS_VALUE;
-
-        if (st->discard < AVDISCARD_ALL)
-            ++keyframes_to_find;
-    }
-
-    if (!keyframes_to_find) {
-        // no stream active, error
-        av_free(sync);
-        return -1;
-    }
-
-    // Find keyframes in all active streams with timestamp/position just before
-    // and just after requested timestamp/position.
-    step = s->pb->buffer_size;
-    curpos = FFMAX(pos - step / 2, 0);
-    for (;;) {
-        avio_seek(s->pb, curpos, SEEK_SET);
-        search_hi_lo_keyframes(s,
-                               ts, time_base,
-                               flags,
-                               sync,
-                               keyframes_to_find,
-                               &found_lo, &found_hi,
-                               first_iter);
-        if (found_lo == keyframes_to_find && found_hi == keyframes_to_find)
-            break;  // have all keyframes we wanted
-        if (!curpos)
-            break;  // cannot go back anymore
-
-        curpos = pos - step;
-        if (curpos < 0)
-            curpos = 0;
-        step *= 2;
-
-        // switch termination positions
-        for (i = 0; i < s->nb_streams; ++i) {
-            st = s->streams[i];
-            st->cur_dts = AV_NOPTS_VALUE;
-
-            sp = &sync[i];
-            if (sp->first_ts != AV_NOPTS_VALUE) {
-                sp->term_ts    = sp->first_ts;
-                sp->term_ts_tb = sp->first_ts_tb;
-                sp->first_ts   = AV_NOPTS_VALUE;
-            }
-            sp->terminated = 0;
-            sp->last_pos = curpos;
-        }
-        first_iter = 0;
-    }
-
-    // Find actual position to start decoding so that decoder synchronizes
-    // closest to ts and between ts_min and ts_max.
-    pos = INT64_MAX;
-
-    for (i = 0; i < s->nb_streams; ++i) {
-        st = s->streams[i];
-        if (st->discard < AVDISCARD_ALL) {
-            sp = &sync[i];
-            min_distance = INT64_MAX;
-            // Find timestamp closest to requested timestamp within min/max limits.
-            if (sp->pos_lo != INT64_MAX
-                && av_compare_ts(ts_min, time_base, sp->ts_lo, st->time_base) <= 0
-                && av_compare_ts(sp->ts_lo, st->time_base, ts_max, time_base) <= 0) {
-                // low timestamp is in range
-                min_distance = ts_distance(ts, time_base, sp->ts_lo, st->time_base);
-                min_pos = sp->pos_lo;
-            }
-            if (sp->pos_hi != INT64_MAX
-                && av_compare_ts(ts_min, time_base, sp->ts_hi, st->time_base) <= 0
-                && av_compare_ts(sp->ts_hi, st->time_base, ts_max, time_base) <= 0) {
-                // high timestamp is in range, check distance
-                distance = ts_distance(sp->ts_hi, st->time_base, ts, time_base);
-                if (distance < min_distance) {
-                    min_distance = distance;
-                    min_pos = sp->pos_hi;
-                }
-            }
-            if (min_distance == INT64_MAX) {
-                // no timestamp is in range, cannot seek
-                av_free(sync);
-                return -1;
-            }
-            if (min_pos < pos)
-                pos = min_pos;
-        }
-    }
-
-    avio_seek(s->pb, pos, SEEK_SET);
-    av_free(sync);
-    return pos;
-}
-
-AVParserState *ff_store_parser_state(AVFormatContext *s)
-{
-    int i;
-    AVStream *st;
-    AVParserStreamState *ss;
-    AVParserState *state = av_malloc(sizeof(AVParserState));
-    if (!state)
-        return NULL;
-
-    state->stream_states = av_malloc(sizeof(AVParserStreamState) * s->nb_streams);
-    if (!state->stream_states) {
-        av_free(state);
-        return NULL;
-    }
-
-    state->fpos = avio_tell(s->pb);
-
-    // copy context structures
-    state->packet_buffer                    = s->packet_buffer;
-    state->parse_queue                      = s->parse_queue;
-    state->raw_packet_buffer                = s->raw_packet_buffer;
-    state->raw_packet_buffer_remaining_size = s->raw_packet_buffer_remaining_size;
-
-    s->packet_buffer                        = NULL;
-    s->parse_queue                          = NULL;
-    s->raw_packet_buffer                    = NULL;
-    s->raw_packet_buffer_remaining_size     = RAW_PACKET_BUFFER_SIZE;
-
-    // copy stream structures
-    state->nb_streams = s->nb_streams;
-    for (i = 0; i < s->nb_streams; i++) {
-        st = s->streams[i];
-        ss = &state->stream_states[i];
-
-        ss->parser        = st->parser;
-        ss->last_IP_pts   = st->last_IP_pts;
-        ss->cur_dts       = st->cur_dts;
-        ss->probe_packets = st->probe_packets;
-
-        st->parser        = NULL;
-        st->last_IP_pts   = AV_NOPTS_VALUE;
-        st->cur_dts       = AV_NOPTS_VALUE;
-        st->probe_packets = MAX_PROBE_PACKETS;
-    }
-
-    return state;
-}
-
-void ff_restore_parser_state(AVFormatContext *s, AVParserState *state)
-{
-    int i;
-    AVStream *st;
-    AVParserStreamState *ss;
-    ff_read_frame_flush(s);
-
-    if (!state)
-        return;
-
-    avio_seek(s->pb, state->fpos, SEEK_SET);
-
-    // copy context structures
-    s->packet_buffer                    = state->packet_buffer;
-    s->parse_queue                      = state->parse_queue;
-    s->raw_packet_buffer                = state->raw_packet_buffer;
-    s->raw_packet_buffer_remaining_size = state->raw_packet_buffer_remaining_size;
-
-    // copy stream structures
-    for (i = 0; i < state->nb_streams; i++) {
-        st = s->streams[i];
-        ss = &state->stream_states[i];
-
-        st->parser        = ss->parser;
-        st->last_IP_pts   = ss->last_IP_pts;
-        st->cur_dts       = ss->cur_dts;
-        st->probe_packets = ss->probe_packets;
-    }
-
-    av_free(state->stream_states);
-    av_free(state);
-}
-
-static void free_packet_list(AVPacketList *pktl)
-{
-    AVPacketList *cur;
-    while (pktl) {
-        cur = pktl;
-        pktl = cur->next;
-        av_free_packet(&cur->pkt);
-        av_free(cur);
-    }
-}
-
-void ff_free_parser_state(AVFormatContext *s, AVParserState *state)
-{
-    int i;
-    AVParserStreamState *ss;
-
-    if (!state)
-        return;
-
-    for (i = 0; i < state->nb_streams; i++) {
-        ss = &state->stream_states[i];
-        if (ss->parser)
-            av_parser_close(ss->parser);
-    }
-
-    free_packet_list(state->packet_buffer);
-    free_packet_list(state->parse_queue);
-    free_packet_list(state->raw_packet_buffer);
-
-    av_free(state->stream_states);
-    av_free(state);
-}
diff --git a/libavformat/seek.h b/libavformat/seek.h
deleted file mode 100644
index 44cd369f4e..0000000000
--- a/libavformat/seek.h
+++ /dev/null
@@ -1,122 +0,0 @@
-/*
- * seek utility functions for use within format handlers
- *
- * Copyright (c) 2009 Ivan Schreter
- *
- * This file is part of Libav.
- *
- * Libav 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.
- *
- * Libav 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 Libav; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-#ifndef AVFORMAT_SEEK_H
-#define AVFORMAT_SEEK_H
-
-#include "avformat.h"
-
-/**
- * structure to store parser state of one AVStream
- */
-typedef struct AVParserStreamState {
-    // saved members of AVStream
-    AVCodecParserContext   *parser;
-    int64_t                 last_IP_pts;
-    int64_t                 cur_dts;
-    int                     probe_packets;
-} AVParserStreamState;
-
-/**
- * structure to store parser state of AVFormat
- */
-typedef struct AVParserState {
-    int64_t         fpos;                   ///< file position at the time of call
-
-    // saved members of AVFormatContext
-    AVPacketList   *packet_buffer;          ///< packet buffer of original state
-    AVPacketList   *parse_queue;            ///< parse queue of original state
-    AVPacketList   *raw_packet_buffer;      ///< raw packet buffer of original state
-    int raw_packet_buffer_remaining_size;   ///< remaining space in raw_packet_buffer
-
-    // saved info for streams
-    int                  nb_streams;        ///< number of streams with stored state
-    AVParserStreamState *stream_states;     ///< states of individual streams (array)
-} AVParserState;
-
-/**
- * Search for the sync point of all active streams.
- *
- * This routine is not supposed to be called directly by a user application,
- * but by demuxers.
- *
- * A sync point is defined as a point in stream, such that, when decoding start
- * from this point, the decoded output of all streams synchronizes closest
- * to the given timestamp ts. This routine also takes timestamp limits into account.
- * Thus, the output will synchronize no sooner than ts_min and no later than ts_max.
- *
- * @param stream_index stream index for time base reference of timestamps
- * @param pos          approximate position where to start searching for key frames
- * @param min_ts       minimum allowed timestamp (position, if AVSEEK_FLAG_BYTE set)
- * @param ts           target timestamp (or position, if AVSEEK_FLAG_BYTE set in flags)
- * @param max_ts       maximum allowed timestamp (position, if AVSEEK_FLAG_BYTE set)
- * @param flags        if AVSEEK_FLAG_ANY is set, seek to any frame, otherwise only
- *                     to a keyframe. If AVSEEK_FLAG_BYTE is set, search by
- *                     position, not by timestamp.
- * @return -1 if no such sync point could be found, otherwise stream position
- *                     (stream is repositioned to this position)
- */
-int64_t ff_gen_syncpoint_search(AVFormatContext *s,
-                                int stream_index,
-                                int64_t pos,
-                                int64_t min_ts,
-                                int64_t ts,
-                                int64_t max_ts,
-                                int flags);
-
-/**
- * Store current parser state and file position.
- *
- * This function can be used by demuxers before a destructive seeking algorithm
- * to store the parser state. Depending on the outcome of the seek, either the original
- * state can be restored or the new state kept and the original state freed.
- *
- * @note As a side effect, the original parser state is reset, since structures
- *       are relinked to the stored state instead of being deeply-copied (for
- *       performance reasons and to keep the code simple).
- *
- * @param s context from which to save state
- * @return parser state object or NULL if memory could not be allocated
- */
-AVParserState *ff_store_parser_state(AVFormatContext *s);
-
-/**
- * Restore previously saved parser state and file position.
- *
- * Saved state will be invalidated and freed by this call, since internal
- * structures will be relinked back to the stored state instead of being
- * deeply-copied.
- *
- * @param s     context to which to restore state (same as used for storing state)
- * @param state state to restore
- */
-void ff_restore_parser_state(AVFormatContext *s, AVParserState *state);
-
-/**
- * Free previously saved parser state.
- *
- * @param s     context to which the state belongs (same as used for storing state)
- * @param state state to free
- */
-void ff_free_parser_state(AVFormatContext *s, AVParserState *state);
-
-#endif /* AVFORMAT_SEEK_H */