Add initial Lua scripting support

This is preliminary. There are still tons of issues, and any aspect
of scripting may change in the future. I decided to merge this
(preliminary) work now because it makes it easier to develop it, not
because it's done. lua.rst is clear enough about it (plus some
sarcasm).

This requires linking to Lua. Lua has no official pkg-config file, but
there are distribution specific .pc files, all with different names.
Adding a non-pkg-config based configure test was considered, but we'd
rather not.

One major complication is that libquvi links against Lua too, and if
the Lua version is different from mpv's, you will get a crash as soon
as libquvi uses Lua. (libquvi by design always runs when a file is
opened.) I would consider this the problem of distros and whoever
builds mpv, but to make things easier for users, we add a terrible
runtime test to the configure script, which probes whether libquvi
will crash. This is disabled when cross-compiling, but in that case
we hope the user knows what he is doing.

1 files changed, 38 insertions, 0 deletions

diff --git a/mpvcore/mplayer.c b/mpvcore/mplayer.c
index fbba387681..50c3db10d7 100644
--- a/mpvcore/mplayer.c
+++ b/mpvcore/mplayer.c
@@ -149,6 +149,8 @@
 #include "mpvcore/mp_core.h"
 #include "mpvcore/options.h"
 
+#include "mp_lua.h"
+
 const char mp_help_text[] = _(
 "Usage:   mpv [options] [url|path/]filename\n"
 "\n"
@@ -548,6 +550,10 @@ static MP_NORETURN void exit_player(struct MPContext *mpctx,
 
     mpctx->encode_lavc_ctx = NULL;
 
+#ifdef CONFIG_LUA
+    mp_lua_uninit(mpctx);
+#endif
+
 #if defined(__MINGW32__) || defined(__CYGWIN__)
     timeEndPeriod(1);
 #endif
@@ -1028,6 +1034,8 @@ static struct track *add_stream_track(struct MPContext *mpctx,
 
     demuxer_select_track(track->demuxer, stream, false);
 
+    mp_notify(mpctx, MP_EVENT_TRACKS_CHANGED, NULL);
+
     return track;
 }
 
@@ -1057,6 +1065,8 @@ static void add_dvd_tracks(struct MPContext *mpctx)
             struct stream_lang_req req = {.type = STREAM_SUB, .id = n};
             stream_control(stream, STREAM_CTRL_GET_LANG, &req);
             track->lang = talloc_strdup(track, req.name);
+
+            mp_notify(mpctx, MP_EVENT_TRACKS_CHANGED, NULL);
         }
     }
     demuxer_enable_autoselect(demuxer);
@@ -2035,12 +2045,15 @@ void mp_switch_track(struct MPContext *mpctx, enum stream_type type,
     if (type == STREAM_VIDEO) {
         mpctx->opts->video_id = user_tid;
         reinit_video_chain(mpctx);
+        mp_notify_property(mpctx, "vid");
     } else if (type == STREAM_AUDIO) {
         mpctx->opts->audio_id = user_tid;
         reinit_audio_chain(mpctx);
+        mp_notify_property(mpctx, "aid");
     } else if (type == STREAM_SUB) {
         mpctx->opts->sub_id = user_tid;
         reinit_subs(mpctx);
+        mp_notify_property(mpctx, "sid");
     }
 
     talloc_free(mpctx->track_layout_hash);
@@ -2083,6 +2096,9 @@ bool mp_remove_track(struct MPContext *mpctx, struct track *track)
     }
     mpctx->num_tracks--;
     talloc_free(track);
+
+    mp_notify(mpctx, MP_EVENT_TRACKS_CHANGED, NULL);
+
     return true;
 }
 
@@ -2761,6 +2777,8 @@ static double update_video(struct MPContext *mpctx, double endpts)
 
 void pause_player(struct MPContext *mpctx)
 {
+    mp_notify_property(mpctx, "pause");
+
     mpctx->opts->pause = 1;
 
     if (mpctx->video_out)
@@ -2790,6 +2808,8 @@ void pause_player(struct MPContext *mpctx)
 
 void unpause_player(struct MPContext *mpctx)
 {
+    mp_notify_property(mpctx, "pause");
+
     mpctx->opts->pause = 0;
 
     if (mpctx->video_out && mpctx->opts->stop_screensaver)
@@ -3418,6 +3438,8 @@ static void handle_cursor_autohide(struct MPContext *mpctx)
 
 static void handle_input_and_seek_coalesce(struct MPContext *mpctx)
 {
+    mp_flush_events(mpctx);
+
     mp_cmd_t *cmd;
     while ((cmd = mp_input_get_cmd(mpctx->input, 0, 1)) != NULL) {
         /* Allow running consecutive seek commands to combine them,
@@ -4216,6 +4238,7 @@ static void idle_loop(struct MPContext *mpctx)
                                         false)));
         run_command(mpctx, cmd);
         mp_cmd_free(cmd);
+        mp_flush_events(mpctx);
     }
 }
 
@@ -4269,6 +4292,10 @@ static void play_current_file(struct MPContext *mpctx)
     double playback_start = -1e100;
 
     mpctx->initialized_flags |= INITIALIZED_PLAYBACK;
+
+    mp_notify(mpctx, MP_EVENT_START_FILE, NULL);
+    mp_flush_events(mpctx);
+
     mpctx->stop_play = 0;
     mpctx->filename = NULL;
 
@@ -4612,6 +4639,10 @@ terminate_playback:  // don't jump here after ao/vo/getch initialization!
                 (playback_start < 0 || mp_time_sec() - playback_start < 3.0);
     if (mpctx->playlist->current && !mpctx->playlist->current_was_replaced)
         mpctx->playlist->current->playback_failed = playback_failed;
+
+    mp_notify(mpctx, MP_EVENT_TRACKS_CHANGED, NULL);
+    mp_notify(mpctx, MP_EVENT_END_FILE, NULL);
+    mp_flush_events(mpctx);
 }
 
 // Determine the next file to play. Note that if this function returns non-NULL,
@@ -4840,6 +4871,7 @@ static int mpv_main(int argc, char *argv[])
     GetCpuCaps(&gCpuCaps);
     screenshot_init(mpctx);
     mpctx->mixer = mixer_init(mpctx, opts);
+    command_init(mpctx);
 
     // Preparse the command line
     m_config_preparse_command_line(mpctx->mconfig, argc, argv);
@@ -4902,6 +4934,12 @@ static int mpv_main(int argc, char *argv[])
 
     mpctx->osd = osd_create(opts, mpctx->ass_library);
 
+#ifdef CONFIG_LUA
+    // Lua user scripts can call arbitrary functions. Load them at a point
+    // where this is safe.
+    mp_lua_init(mpctx);
+#endif
+
     if (opts->shuffle)
         playlist_shuffle(mpctx->playlist);