player: simplify an aspect of buffering determination

Calculate the buffering percentage in the same code which determines
whether the player is or should be buffering. In particular it can't
happen that percentage and buffering state are slightly out of sync due
to calling DEMUXER_CTRL_GET_READER_STATE and reusing it with the
previously determined buffering state.

Now it's also easier to guarantee that the buffering state is updated
properly.

Add some more verbose output as well.

(Damn I hate this code, why did I write it?)

1 files changed, 30 insertions, 15 deletions

diff --git a/player/playloop.c b/player/playloop.c
index d6509f8c98..a7b21850dd 100644
--- a/player/playloop.c
+++ b/player/playloop.c
@@ -518,6 +518,7 @@ static void handle_osd_redraw(struct MPContext *mpctx)
 
 static void handle_pause_on_low_cache(struct MPContext *mpctx)
 {
+    bool force_update = false;
     struct MPOpts *opts = mpctx->opts;
     if (!mpctx->demuxer)
         return;
@@ -529,6 +530,8 @@ static void handle_pause_on_low_cache(struct MPContext *mpctx)
     struct demux_ctrl_reader_state s = {.idle = true, .ts_duration = -1};
     demux_control(mpctx->demuxer, DEMUXER_CTRL_GET_READER_STATE, &s);
 
+    int cache_buffer = 100;
+
     if (mpctx->restart_complete && idle != -1) {
         if (mpctx->paused && mpctx->paused_for_cache) {
             if (!opts->cache_pausing || s.ts_duration >= mpctx->cache_wait_time
@@ -543,7 +546,7 @@ static void handle_pause_on_low_cache(struct MPContext *mpctx)
                 mpctx->paused_for_cache = false;
                 if (!opts->pause)
                     unpause_player(mpctx);
-                mp_notify(mpctx, MP_EVENT_CACHE_UPDATE, NULL);
+                force_update = true;
             }
             mpctx->sleeptime = MPMIN(mpctx->sleeptime, 0.2);
         } else {
@@ -553,10 +556,14 @@ static void handle_pause_on_low_cache(struct MPContext *mpctx)
                 mpctx->paused_for_cache = true;
                 opts->pause = prev_paused_user;
                 mpctx->cache_stop_time = mp_time_sec();
-                mp_notify(mpctx, MP_EVENT_CACHE_UPDATE, NULL);
+                force_update = true;
             }
         }
         mpctx->cache_wait_time = MPCLAMP(mpctx->cache_wait_time, 1, 10);
+        if (mpctx->paused_for_cache) {
+            cache_buffer =
+                100 * MPCLAMP(s.ts_duration / mpctx->cache_wait_time, 0, 0.99);
+        }
     }
 
     // Also update cache properties.
@@ -569,28 +576,36 @@ static void handle_pause_on_low_cache(struct MPContext *mpctx)
         double now = mp_time_sec();
         if (mpctx->next_cache_update <= now) {
             mpctx->next_cache_update = busy ? now + 0.25 : 0;
-            mp_notify(mpctx, MP_EVENT_CACHE_UPDATE, NULL);
+            force_update = true;
         }
         if (mpctx->next_cache_update > 0) {
             mpctx->sleeptime =
                 MPMIN(mpctx->sleeptime, mpctx->next_cache_update - now);
         }
     }
+
+    if (mpctx->cache_buffer != cache_buffer) {
+        if (mpctx->cache_buffer >= 0 &&
+            (mpctx->cache_buffer == 100) != (cache_buffer == 100))
+        {
+            if (cache_buffer < 100) {
+                MP_VERBOSE(mpctx, "Enter buffering.\n");
+            } else {
+                double t = mp_time_sec() - mpctx->cache_stop_time;
+                MP_VERBOSE(mpctx, "End buffering (waited %f secs).\n", t);
+            }
+        }
+        mpctx->cache_buffer = cache_buffer;
+        force_update = true;
+    }
+
+    if (force_update)
+        mp_notify(mpctx, MP_EVENT_CACHE_UPDATE, NULL);
 }
 
-double get_cache_buffering_percentage(struct MPContext *mpctx)
+int get_cache_buffering_percentage(struct MPContext *mpctx)
 {
-    if (mpctx->demuxer && mpctx->paused_for_cache && mpctx->cache_wait_time > 0) {
-        struct demux_ctrl_reader_state s = {.idle = true, .ts_duration = -1};
-        demux_control(mpctx->demuxer, DEMUXER_CTRL_GET_READER_STATE, &s);
-        if (s.ts_duration < 0)
-            s.ts_duration = 0;
-
-        return MPCLAMP(s.ts_duration / mpctx->cache_wait_time, 0.0, 1.0);
-    }
-    if (mpctx->demuxer && !mpctx->paused_for_cache)
-        return 1.0;
-    return -1;
+    return mpctx->demuxer ? mpctx->cache_buffer : -1;
 }
 
 static void handle_heartbeat_cmd(struct MPContext *mpctx)