demux: remove facility for partial packet reads

Partial packet reads were needed because the video/audio parsers were
working on top of them. So it could happen that a parser read a part of
a packet, and returned that to the decoder. With libavformat/libavcodec,
packets are already parsed, and everything is much simpler.

Most of the simplifications in ad_spdif could have been done earlier.
Remove some other stuff as well, like the questionable slave mode start
time reporting (could be replaced by proper code, but we don't bother).
Remove the unused skip_audio_frame() functionality as well (it was used
by old demuxers). Some functions become private to demux.c, like
demux_fill_buffer(). Introduce new packet read functions, which have
simpler semantics. Packets returned from them are owned by the caller,
and all packets in the demux.c packet queue are considered unread.
Remove special code that dropped subtitle packets with size 0. This
used to be needed because it caused special cases in the old code.

1 files changed, 30 insertions, 56 deletions

diff --git a/core/mplayer.c b/core/mplayer.c
index 217e99ed5c..0d07b518d8 100644
--- a/core/mplayer.c
+++ b/core/mplayer.c
@@ -288,8 +288,6 @@ static void print_stream(struct MPContext *mpctx, struct track *t)
 
 static void print_file_properties(struct MPContext *mpctx, const char *filename)
 {
-    double start_pts = MP_NOPTS_VALUE;
-    double video_start_pts = MP_NOPTS_VALUE;
     mp_msg(MSGT_IDENTIFY, MSGL_INFO, "ID_FILENAME=%s\n",
            filename);
     if (mpctx->sh_video) {
@@ -310,7 +308,6 @@ static void print_file_properties(struct MPContext *mpctx, const char *filename)
                "ID_VIDEO_FPS=%5.3f\n", mpctx->sh_video->fps);
         mp_msg(MSGT_IDENTIFY, MSGL_INFO,
                "ID_VIDEO_ASPECT=%1.4f\n", mpctx->sh_video->aspect);
-        video_start_pts = ds_get_next_pts(mpctx->sh_video->ds);
     }
     if (mpctx->sh_audio) {
         /* Assume FOURCC if all bytes >= 0x20 (' ') */
@@ -326,17 +323,7 @@ static void print_file_properties(struct MPContext *mpctx, const char *filename)
                "ID_AUDIO_RATE=%d\n", mpctx->sh_audio->samplerate);
         mp_msg(MSGT_IDENTIFY, MSGL_INFO,
                "ID_AUDIO_NCH=%d\n", mpctx->sh_audio->channels.num);
-        start_pts = ds_get_next_pts(mpctx->sh_audio->ds);
     }
-    if (video_start_pts != MP_NOPTS_VALUE) {
-        if (start_pts == MP_NOPTS_VALUE || !mpctx->sh_audio ||
-            (mpctx->sh_video && video_start_pts < start_pts))
-            start_pts = video_start_pts;
-    }
-    if (start_pts != MP_NOPTS_VALUE)
-        mp_msg(MSGT_IDENTIFY, MSGL_INFO, "ID_START_TIME=%.2f\n", start_pts);
-    else
-        mp_msg(MSGT_IDENTIFY, MSGL_INFO, "ID_START_TIME=unknown\n");
     mp_msg(MSGT_IDENTIFY, MSGL_INFO,
            "ID_LENGTH=%.2f\n", get_time_length(mpctx));
     int chapter_count = get_chapter_count(mpctx);
@@ -375,11 +362,8 @@ static double get_main_demux_pts(struct MPContext *mpctx)
     if (mpctx->demuxer) {
         for (int type = 0; type < STREAM_TYPE_COUNT; type++) {
             struct demux_stream *ds = mpctx->demuxer->ds[type];
-            if (ds->gsh && main_new_pos == MP_NOPTS_VALUE) {
-                demux_fill_buffer(mpctx->demuxer, ds);
-                if (ds->first)
-                    main_new_pos = ds->first->pts;
-            }
+            if (ds->gsh && main_new_pos == MP_NOPTS_VALUE)
+                main_new_pos = demux_get_next_pts(ds->gsh);
         }
     }
     return main_new_pos;
@@ -1703,14 +1687,14 @@ static double written_audio_pts(struct MPContext *mpctx)
         // ratio is not constant for every audio packet or if it is constant
         // but not accurately known in sh_audio->i_bps.
 
-        a_pts = d_audio->pts;
+        a_pts = d_audio->last_pts;
         if (a_pts == MP_NOPTS_VALUE)
             return a_pts;
 
         // ds_tell_pts returns bytes read after last timestamp from
         // demuxing layer
         if (sh_audio->i_bps)
-            a_pts += ds_tell_pts(d_audio) / (double)sh_audio->i_bps;
+            a_pts += d_audio->last_pts_bytes / (double)sh_audio->i_bps;
     }
     // Now a_pts hopefully holds the pts for end of audio from decoder.
     // Substract data in buffers between decoder and audio out.
@@ -1783,15 +1767,14 @@ static void update_subtitles(struct MPContext *mpctx, double refpts_tl)
     double curpts_s = refpts_s + opts->sub_delay;
 
     if (!track->preloaded) {
-        struct demux_stream *d_sub = sh_sub->ds;
         bool non_interleaved = is_non_interleaved(mpctx, track);
 
         while (1) {
-            if (non_interleaved)
-                ds_get_next_pts(d_sub);
-            if (!d_sub->first)
+            if (!non_interleaved && !demux_has_packet(sh_sub->gsh))
+                break;
+            double subpts_s = demux_get_next_pts(sh_sub->gsh);
+            if (!demux_has_packet(sh_sub->gsh))
                 break;
-            double subpts_s = ds_get_next_pts(d_sub);
             if (subpts_s > curpts_s) {
                 mp_dbg(MSGT_CPLAYER, MSGL_DBG2,
                        "Sub early: c_pts=%5.3f s_pts=%5.3f\n",
@@ -1803,11 +1786,12 @@ static void update_subtitles(struct MPContext *mpctx, double refpts_tl)
                 if (non_interleaved && subpts_s > curpts_s + 1)
                     break;
             }
-            struct demux_packet *pkt = ds_get_packet_sub(d_sub);
+            struct demux_packet *pkt = demux_read_packet(sh_sub->gsh);
             mp_dbg(MSGT_CPLAYER, MSGL_V, "Sub: c_pts=%5.3f s_pts=%5.3f "
                    "duration=%5.3f len=%d\n", curpts_s, pkt->pts, pkt->duration,
                    pkt->len);
             sub_decode(dec_sub, pkt);
+            talloc_free(pkt);
         }
     }
 
@@ -2465,28 +2449,24 @@ static void filter_video(struct MPContext *mpctx, struct mp_image *frame)
 }
 
 
-static int video_read_frame(sh_video_t *sh_video,
-                            unsigned char **start, int force_fps)
+static struct demux_packet *video_read_frame(struct MPContext *mpctx)
 {
+    sh_video_t *sh_video = mpctx->sh_video;
     demux_stream_t *d_video = sh_video->ds;
     demuxer_t *demuxer = d_video->demuxer;
-    float pts1 = d_video->pts;
-    int in_size = 0;
-
-    *start = NULL;
+    float pts1 = d_video->last_pts;
 
-    // frame-based file formats: (AVI,ASF,MOV)
-    in_size = ds_get_packet(d_video, start);
-    if (in_size < 0)
-        return -1; // EOF
+    struct demux_packet *pkt = demux_read_packet(sh_video->gsh);
+    if (!pkt)
+        return NULL; // EOF
 
     float frame_time = sh_video->frametime;
 
     // override frame_time for variable/unknown FPS formats:
-    if (!force_fps) {
-        double next_pts = ds_get_next_pts(d_video);
-        double d = next_pts == MP_NOPTS_VALUE ? d_video->pts - pts1
-                                              : next_pts - d_video->pts;
+    if (!mpctx->opts.force_fps) {
+        double next_pts = demux_get_next_pts(sh_video->gsh);
+        double d = next_pts == MP_NOPTS_VALUE ? d_video->last_pts - pts1
+                                              : next_pts - d_video->last_pts;
         if (d >= 0) {
             if (demuxer->file_format == DEMUXER_TYPE_TV) {
                 if (d > 0) {
@@ -2501,10 +2481,10 @@ static int video_read_frame(sh_video_t *sh_video,
         }
     }
 
-    sh_video->pts = d_video->pts;
+    sh_video->pts = d_video->last_pts;
 
     sh_video->next_frame_time = frame_time;
-    return in_size;
+    return pkt;
 }
 
 static double update_video_nocorrect_pts(struct MPContext *mpctx)
@@ -2518,15 +2498,11 @@ static double update_video_nocorrect_pts(struct MPContext *mpctx)
             break;
         if (filter_output_queued_frame(mpctx))
             break;
-        unsigned char *packet = NULL;
         frame_time = sh_video->next_frame_time;
         if (mpctx->restart_playback)
             frame_time = 0;
-        int in_size = 0;
-        while (!in_size)
-            in_size = video_read_frame(sh_video,
-                                       &packet, mpctx->opts.force_fps);
-        if (in_size < 0)
+        struct demux_packet *pkt = video_read_frame(mpctx);
+        if (!pkt)
             return -1;
         if (mpctx->sh_audio)
             mpctx->delay -= frame_time;
@@ -2534,13 +2510,9 @@ static double update_video_nocorrect_pts(struct MPContext *mpctx)
         update_fps(mpctx);
         int framedrop_type = check_framedrop(mpctx, frame_time);
 
-        struct demux_packet pkt = {0};
-        if (sh_video->ds->current)
-            pkt = *sh_video->ds->current;
-        pkt.buffer = packet;
-        pkt.len = in_size;
-        void *decoded_frame = decode_video(sh_video, &pkt, framedrop_type,
+        void *decoded_frame = decode_video(sh_video, pkt, framedrop_type,
                                            sh_video->pts);
+        talloc_free(pkt);
         if (decoded_frame) {
             filter_video(mpctx, decoded_frame);
         }
@@ -2599,12 +2571,13 @@ static double update_video(struct MPContext *mpctx, double endpts)
         pts = MP_NOPTS_VALUE;
         struct demux_packet *pkt;
         while (1) {
-            pkt = ds_get_packet2(mpctx->sh_video->ds, false);
+            pkt = demux_read_packet(mpctx->sh_video->gsh);
             if (!pkt || pkt->len)
                 break;
             /* Packets with size 0 are assumed to not correspond to frames,
              * but to indicate the absence of a frame in formats like AVI
              * that must have packets at fixed timecode intervals. */
+            talloc_free(pkt);
         }
         if (pkt)
             pts = pkt->pts;
@@ -2616,6 +2589,7 @@ static double update_video(struct MPContext *mpctx, double endpts)
                              1 : check_framedrop(mpctx, sh_video->frametime);
         struct mp_image *decoded_frame =
             decode_video(sh_video, pkt, framedrop_type, pts);
+        talloc_free(pkt);
         if (decoded_frame) {
             determine_frame_pts(mpctx);
             filter_video(mpctx, decoded_frame);
@@ -2773,7 +2747,7 @@ static void seek_reset(struct MPContext *mpctx, bool reset_ao, bool reset_ac)
         // Not all demuxers set d_video->pts during seek, so this value
         // (which was used by at least vobsub code below) may be completely
         // wrong (probably 0).
-        mpctx->sh_video->pts = mpctx->sh_video->ds->pts + mpctx->video_offset;
+        mpctx->sh_video->pts = mpctx->sh_video->ds->last_pts + mpctx->video_offset;
         mpctx->video_pts = mpctx->sh_video->pts;
     }