player: slightly improve use of secondary track selection limits

Apparently, this was a bit of a mess, which caused the bug fixed by
commit ec7f2388af2df. Try to improve this, and only use track selection
entries that exist.

6 files changed, 28 insertions, 20 deletions

diff --git a/options/options.c b/options/options.c
index 3536e439a0..881810589d 100644
--- a/options/options.c
+++ b/options/options.c
@@ -467,6 +467,7 @@ static const m_option_t mp_opts[] = {
      {"index", OPT_CHOICE(index_mode, {"default", 1}, {"recreate", 0})},
 
     // select audio/video/subtitle stream
+    // keep in sync with num_ptracks[] and MAX_PTRACKS
     {"aid", OPT_TRACKCHOICE(stream_id[0][STREAM_AUDIO])},
     {"vid", OPT_TRACKCHOICE(stream_id[0][STREAM_VIDEO])},
     {"sid", OPT_TRACKCHOICE(stream_id[0][STREAM_SUB])},
diff --git a/player/command.c b/player/command.c
index 8c383a930b..c10c4374aa 100644
--- a/player/command.c
+++ b/player/command.c
@@ -6224,7 +6224,7 @@ void mp_option_change_callback(void *ctx, struct m_config_option *co, int flags,
         mp_update_logging(mpctx, false);
 
     if (flags & (UPDATE_OSD | UPDATE_SUB_FILT)) {
-        for (int n = 0; n < NUM_PTRACKS; n++) {
+        for (int n = 0; n < num_ptracks[STREAM_SUB]; n++) {
             struct track *track = mpctx->current_track[n][STREAM_SUB];
             struct dec_sub *sub = track ? track->d_sub : NULL;
             if (sub) {
@@ -6352,8 +6352,8 @@ void mp_option_change_callback(void *ctx, struct m_config_option *co, int flags,
     if (opt_ptr == &opts->af_settings)
         set_filters(mpctx, STREAM_AUDIO, opts->af_settings);
 
-    for (int order = 0; order < NUM_PTRACKS; order++) {
-        for (int type = 0; type < STREAM_TYPE_COUNT; type++) {
+    for (int type = 0; type < STREAM_TYPE_COUNT; type++) {
+        for (int order = 0; order < num_ptracks[type]; order++) {
             if (opt_ptr == &opts->stream_id[order][type] &&
                 mpctx->playback_initialized)
             {
diff --git a/player/core.h b/player/core.h
index a13fa2852b..bbd3f5ce33 100644
--- a/player/core.h
+++ b/player/core.h
@@ -232,7 +232,10 @@ enum playback_status {
 
 const char *mp_status_str(enum playback_status st);
 
-#define NUM_PTRACKS 2
+extern const int num_ptracks[STREAM_TYPE_COUNT];
+
+// Maximum of all num_ptracks[] values.
+#define MAX_PTRACKS 2
 
 typedef struct MPContext {
     bool initialized;
@@ -309,9 +312,9 @@ typedef struct MPContext {
     char *track_layout_hash;
 
     // Selected tracks. NULL if no track selected.
-    // There can be NUM_PTRACKS of the same STREAM_TYPE selected at once.
+    // There can be num_ptracks[type] of the same STREAM_TYPE selected at once.
     // Currently, this is used for the secondary subtitle track only.
-    struct track *current_track[NUM_PTRACKS][STREAM_TYPE_COUNT];
+    struct track *current_track[MAX_PTRACKS][STREAM_TYPE_COUNT];
 
     struct mp_filter *filter_root;
 
diff --git a/player/loadfile.c b/player/loadfile.c
index 5972c634be..8461731518 100644
--- a/player/loadfile.c
+++ b/player/loadfile.c
@@ -193,8 +193,8 @@ static void kill_demuxers_reentrant(struct MPContext *mpctx,
 
 static void uninit_demuxer(struct MPContext *mpctx)
 {
-    for (int r = 0; r < NUM_PTRACKS; r++) {
-        for (int t = 0; t < STREAM_TYPE_COUNT; t++)
+    for (int t = 0; t < STREAM_TYPE_COUNT; t++) {
+        for (int r = 0; r < num_ptracks[t]; r++)
             mpctx->current_track[r][t] = NULL;
     }
 
@@ -572,7 +572,7 @@ static void check_previous_track_selection(struct MPContext *mpctx)
         // Reset selection, but only if they're not "auto" or "off". The
         // defaults are -1 (default selection), or -2 (off) for secondary tracks.
         for (int t = 0; t < STREAM_TYPE_COUNT; t++) {
-            for (int i = 0; i < NUM_PTRACKS; i++) {
+            for (int i = 0; i < num_ptracks[t]; i++) {
                 if (opts->stream_id[i][t] >= 0) {
                     opts->stream_id[i][t] = i == 0 ? -1 : -2;
                     m_config_notify_change_opt_ptr(mpctx->mconfig,
@@ -589,10 +589,8 @@ static void check_previous_track_selection(struct MPContext *mpctx)
 static void mark_track_selection(struct MPContext *mpctx, int order,
                                  enum stream_type type, int value)
 {
-    assert(order >= 0 && order < NUM_PTRACKS);
+    assert(order >= 0 && order < num_ptracks[type]);
     mpctx->opts->stream_id[order][type] = value;
-    if (type != STREAM_SUB && order != 0)
-        return; // mconfig only contains one track for vid/aid
     m_config_notify_change_opt_ptr(mpctx->mconfig,
                                    &mpctx->opts->stream_id[order][type]);
 }
@@ -601,7 +599,8 @@ void mp_switch_track_n(struct MPContext *mpctx, int order, enum stream_type type
                        struct track *track, int flags)
 {
     assert(!track || track->type == type);
-    assert(order >= 0 && order < NUM_PTRACKS);
+    assert(type >= 0 && type < STREAM_TYPE_COUNT);
+    assert(order >= 0 && order < num_ptracks[type]);
 
     // Mark the current track selection as explicitly user-requested. (This is
     // different from auto-selection or disabling a track due to errors.)
@@ -690,7 +689,7 @@ void mp_switch_track(struct MPContext *mpctx, enum stream_type type,
 void mp_deselect_track(struct MPContext *mpctx, struct track *track)
 {
     if (track && track->selected) {
-        for (int t = 0; t < NUM_PTRACKS; t++) {
+        for (int t = 0; t < num_ptracks[track->type]; t++) {
             mp_switch_track_n(mpctx, t, track->type, NULL, 0);
             mark_track_selection(mpctx, t, track->type, -1); // default
         }
@@ -1525,9 +1524,8 @@ static void play_current_file(struct MPContext *mpctx)
     if (reinit_complex_filters(mpctx, false) < 0)
         goto terminate_playback;
 
-    assert(NUM_PTRACKS == 2); // opts->stream_id is hardcoded to 2
     for (int t = 0; t < STREAM_TYPE_COUNT; t++) {
-        for (int i = 0; i < NUM_PTRACKS; i++) {
+        for (int i = 0; i < num_ptracks[t]; i++) {
             struct track *sel = NULL;
             bool taken = (t == STREAM_VIDEO && mpctx->vo_chain) ||
                          (t == STREAM_AUDIO && mpctx->ao_chain);
@@ -1537,7 +1535,7 @@ static void play_current_file(struct MPContext *mpctx)
         }
     }
     for (int t = 0; t < STREAM_TYPE_COUNT; t++) {
-        for (int i = 0; i < NUM_PTRACKS; i++) {
+        for (int i = 0; i < num_ptracks[t]; i++) {
             // One track can strictly feed at most 1 decoder
             struct track *track = mpctx->current_track[i][t];
             if (track) {
diff --git a/player/misc.c b/player/misc.c
index 4246c1c6f9..e8cebbc2e6 100644
--- a/player/misc.c
+++ b/player/misc.c
@@ -45,6 +45,12 @@
 #include "core.h"
 #include "command.h"
 
+const int num_ptracks[STREAM_TYPE_COUNT] = {
+    [STREAM_VIDEO] = 1,
+    [STREAM_AUDIO] = 1,
+    [STREAM_SUB] = 2,
+};
+
 double rel_time_to_abs(struct MPContext *mpctx, struct m_rel_time t)
 {
     double length = get_time_length(mpctx);
diff --git a/player/sub.c b/player/sub.c
index 599430ac21..a40a6d5e9d 100644
--- a/player/sub.c
+++ b/player/sub.c
@@ -39,7 +39,7 @@
 // 0: primary sub, 1: secondary sub, -1: not selected
 static int get_order(struct MPContext *mpctx, struct track *track)
 {
-    for (int n = 0; n < NUM_PTRACKS; n++) {
+    for (int n = 0; n < num_ptracks[STREAM_SUB]; n++) {
         if (mpctx->current_track[n][STREAM_SUB] == track)
             return n;
     }
@@ -129,7 +129,7 @@ static bool update_subtitle(struct MPContext *mpctx, double video_pts,
 bool update_subtitles(struct MPContext *mpctx, double video_pts)
 {
     bool ok = true;
-    for (int n = 0; n < NUM_PTRACKS; n++)
+    for (int n = 0; n < num_ptracks[STREAM_SUB]; n++)
         ok &= update_subtitle(mpctx, video_pts, mpctx->current_track[n][STREAM_SUB]);
     return ok;
 }
@@ -201,6 +201,6 @@ void reinit_sub(struct MPContext *mpctx, struct track *track)
 
 void reinit_sub_all(struct MPContext *mpctx)
 {
-    for (int n = 0; n < NUM_PTRACKS; n++)
+    for (int n = 0; n < num_ptracks[STREAM_SUB]; n++)
         reinit_sub(mpctx, mpctx->current_track[n][STREAM_SUB]);
 }