demux, command: export bof/eof flags

Export these flags with demuxer-cache-state. Useful for debugging, but
any client API users could also make use of it.

DOCS/man/input.rst

@@ -1450,6 +1450,13 @@ Property list
     buffering amount, while the seek ranges represent the buffered data that
     can actually be used for cached seeking.
 
+    ``bof-cached`` indicates whether the seek range with the lowest timestamp
+    points to the beginning of the stream (BOF). This implies you cannot seek
+    before this position at all. ``eof-cached`` indicates whether the seek range
+    with the highest timestamp points to the end of the stream (EOF). If both
+    ``bof-cached`` and ``eof-cached`` are set to ``yes``, the entire stream is
+    cached.
+
     ``fw-bytes`` is the number of bytes of packets buffered in the range
     starting from the current decoding position.
 
@@ -1464,6 +1471,8 @@ Property list
                 MPV_FORMAT_NODE_MAP
                     "start"             MPV_FORMAT_DOUBLE
                     "end"               MPV_FORMAT_DOUBLE
+            "bof-cached"        MPV_FORMAT_FLAG
+            "eof-cached"        MPV_FORMAT_FLAG
             "fw-bytes"          MPV_FORMAT_INT64
 
     Other fields (might be changed or removed in the future):

demux/demux.c

@@ -3227,6 +3227,8 @@ void demux_get_reader_state(struct demuxer *demuxer, struct demux_reader_state *
                     .start = MP_ADD_PTS(range->seek_start, in->ts_offset),
                     .end = MP_ADD_PTS(range->seek_end, in->ts_offset),
                 };
+            r->bof_cached |= range->is_bof;
+            r->eof_cached |= range->is_eof;
         }
     }
 

demux/demux.h

@@ -38,6 +38,7 @@ struct demux_seek_range {
 
 struct demux_reader_state {
     bool eof, underrun, idle;
+    bool bof_cached, eof_cached;
     double ts_duration;
     double ts_reader; // approx. timerstamp of decoder position
     double ts_end; // approx. timestamp of end of buffered range

player/command.c

@@ -1502,6 +1502,9 @@ static int mp_property_demuxer_cache_state(void *ctx, struct m_property *prop,
     struct mpv_node *r = (struct mpv_node *)arg;
     node_init(r, MPV_FORMAT_NODE_MAP, NULL);
 
+    node_map_add_flag(r, "bof-cached", s.bof_cached);
+    node_map_add_flag(r, "eof-cached", s.eof_cached);
+
     struct mpv_node *ranges =
         node_map_add(r, "seekable-ranges", MPV_FORMAT_NODE_ARRAY);
     for (int n = 0; n < s.num_seek_ranges; n++) {