player: change the role of the "stop_play" and "playing" variable

Before this, mpctx->playing was often used to determine whether certain
new state could be added to the playback state. In particular this
affected external files (which added tracks and demuxers). The variable
was checked to prevent that they were added before the corresponding
uninit code. We want to make a small part of uninit asynchronous, but
mpctx->playing needs to stay in the place where it is. It can't be used
for this purpose anymore.

Use mpctx->stop_play instead. Make it never have the value 0 outside of
loading/playback. On unloading, it obviously has to be non-0.

Change some other code in playloop.c to use this, because it seems
slightly more correct. But mostly this is preparation for the following
commit.

1 files changed, 14 insertions, 11 deletions

diff --git a/player/loadfile.c b/player/loadfile.c
index 39ba179c02..a28bf491b4 100644
--- a/player/loadfile.c
+++ b/player/loadfile.c
@@ -662,7 +662,7 @@ int mp_add_external_file(struct MPContext *mpctx, char *filename,
 
     // The command could have overlapped with playback exiting. (We don't care
     // if playback has started again meanwhile - weird, but not a problem.)
-    if (!mpctx->playing)
+    if (mpctx->stop_play)
         goto err_out;
 
     if (!demuxer)
@@ -1248,6 +1248,8 @@ static void play_current_file(struct MPContext *mpctx)
     struct MPOpts *opts = mpctx->opts;
     double playback_start = -1e100;
 
+    assert(mpctx->stop_play);
+
     mp_notify(mpctx, MPV_EVENT_START_FILE, NULL);
 
     mp_cancel_reset(mpctx->playback_abort);
@@ -1473,16 +1475,16 @@ static void play_current_file(struct MPContext *mpctx)
 
 terminate_playback:
 
-    update_core_idle_state(mpctx);
-
-    process_hooks(mpctx, "on_unload");
-
-    if (mpctx->stop_play == KEEP_PLAYING)
-        mpctx->stop_play = AT_END_OF_FILE;
+    if (!mpctx->stop_play)
+        mpctx->stop_play = PT_ERROR;
 
     if (mpctx->stop_play != AT_END_OF_FILE)
         clear_audio_output_buffers(mpctx);
 
+    update_core_idle_state(mpctx);
+
+    process_hooks(mpctx, "on_unload");
+
     if (mpctx->step_frames)
         opts->pause = 1;
 
@@ -1550,8 +1552,6 @@ terminate_playback:
 
     if (mpctx->playing)
         playlist_entry_unref(mpctx->playing);
-    // Note: a lot of things assume that the core won't be unlocked between
-    // uninitializing various playback-only resources (such as tracks).
     mpctx->playing = NULL;
     talloc_free(mpctx->filename);
     mpctx->filename = NULL;
@@ -1564,6 +1564,8 @@ terminate_playback:
     } else {
         mpctx->files_played++;
     }
+
+    assert(mpctx->stop_play);
 }
 
 // Determine the next file to play. Note that if this function returns non-NULL,
@@ -1629,6 +1631,7 @@ void mp_play_files(struct MPContext *mpctx)
     prepare_playlist(mpctx, mpctx->playlist);
 
     for (;;) {
+        assert(mpctx->stop_play);
         idle_loop(mpctx);
         if (mpctx->stop_play == PT_QUIT)
             break;
@@ -1639,14 +1642,14 @@ void mp_play_files(struct MPContext *mpctx)
 
         struct playlist_entry *new_entry = mpctx->playlist->current;
         if (mpctx->stop_play == PT_NEXT_ENTRY || mpctx->stop_play == PT_ERROR ||
-            mpctx->stop_play == AT_END_OF_FILE || !mpctx->stop_play)
+            mpctx->stop_play == AT_END_OF_FILE || mpctx->stop_play == PT_STOP)
         {
             new_entry = mp_next_file(mpctx, +1, false, true);
         }
 
         mpctx->playlist->current = new_entry;
         mpctx->playlist->current_was_replaced = false;
-        mpctx->stop_play = 0;
+        mpctx->stop_play = PT_STOP;
 
         if (!mpctx->playlist->current && mpctx->opts->player_idle_mode < 2)
             break;