demux: rename a function

Also extend the comment on it.

1 files changed, 7 insertions, 3 deletions

diff --git a/demux/demux.c b/demux/demux.c
index 4b6536ef29..a94d98e10f 100644
--- a/demux/demux.c
+++ b/demux/demux.c
@@ -798,13 +798,17 @@ static struct demux_packet *dequeue_packet(struct demux_stream *ds)
     return pkt;
 }
 
+// Whether to avoid actively demuxing new packets to find a new packet on the
+// given stream.
 // Sparse packets (Subtitles) interleaved with other non-sparse packets (video,
 // audio) should never be read actively, meaning the demuxer thread does not
 // try to exceed default readahead in order to find a new packet.
-static bool use_lazy_subtitle_reading(struct demux_stream *ds)
+static bool use_lazy_packet_reading(struct demux_stream *ds)
 {
     if (ds->type != STREAM_SUB)
         return false;
+    // Subtitles are only lazily read if there's at least 1 other actively read
+    // stream.
     for (int n = 0; n < ds->in->num_streams; n++) {
         struct demux_stream *s = ds->in->streams[n]->ds;
         if (s->type != STREAM_SUB && s->selected && !s->eof)
@@ -823,7 +827,7 @@ struct demux_packet *demux_read_packet(struct sh_stream *sh)
     if (ds) {
         struct demux_internal *in = ds->in;
         pthread_mutex_lock(&in->lock);
-        if (!use_lazy_subtitle_reading(ds)) {
+        if (!use_lazy_packet_reading(ds)) {
             const char *t = stream_type_name(ds->type);
             MP_DBG(in, "reading packet for %s\n", t);
             in->eof = false; // force retry
@@ -869,7 +873,7 @@ int demux_read_packet_async(struct sh_stream *sh, struct demux_packet **out_pkt)
         if (ds->in->threading) {
             pthread_mutex_lock(&ds->in->lock);
             *out_pkt = dequeue_packet(ds);
-            if (use_lazy_subtitle_reading(ds)) {
+            if (use_lazy_packet_reading(ds)) {
                 r = *out_pkt ? 1 : -1;
             } else {
                 r = *out_pkt ? 1 : ((ds->eof || !ds->selected) ? -1 : 0);