sub: respect detected language for fuzzy-matched external subtitles

Solve this by passing through the language to the player, which then
uses the generic subtitle selection code to make a choice.

Fixes #367.

mpvcore/player/loadfile.c

@@ -697,20 +697,23 @@ static void open_subtitles_from_options(struct MPContext *mpctx)
             mp_add_subtitles(mpctx, mpctx->opts->sub_name[i]);
     }
     if (mpctx->opts->sub_auto) { // auto load sub file ...
-        char **tmp = find_text_subtitles(mpctx->opts, mpctx->filename);
-        int nsub = MP_TALLOC_ELEMS(tmp);
-        for (int i = 0; i < nsub; i++) {
-            char *filename = tmp[i];
+        struct subfn *list = find_text_subtitles(mpctx->opts, mpctx->filename);
+        for (int i = 0; list[i].fname; i++) {
+            char *filename = list[i].fname;
+            char *lang = list[i].lang;
             for (int n = 0; n < mpctx->num_sources; n++) {
                 if (strcmp(mpctx->sources[n]->stream->url, filename) == 0)
                     goto skip;
             }
             struct track *track = mp_add_subtitles(mpctx, filename);
-            if (track)
+            if (track) {
                 track->auto_loaded = true;
+                if (!track->lang)
+                    track->lang = talloc_strdup(track, lang);
+            }
         skip:;
         }
-        talloc_free(tmp);
+        talloc_free(list);
     }
 }
 

sub/find_subfiles.c

@@ -41,11 +41,6 @@ static struct bstr get_ext(struct bstr s)
     return bstr_splice(s, dotpos + 1, s.len);
 }
 
-struct subfn {
-    int priority;
-    char *fname;
-};
-
 static int compare_sub_filename(const void *a, const void *b)
 {
     const struct subfn *s1 = a;
@@ -135,14 +130,15 @@ static void append_dir_subtitles(struct MPOpts *opts,
 
         // we have a (likely) subtitle file
         int prio = 0;
+        char *found_lang = NULL;
         if (opts->sub_lang) {
             if (bstr_startswith(tmp_fname_trim, f_fname_trim)) {
                 struct bstr lang = guess_lang_from_filename(tmp_fname_trim);
                 if (lang.len) {
                     for (int n = 0; opts->sub_lang[n]; n++) {
-                        if (bstr_startswith(lang,
-                                            bstr0(opts->sub_lang[n]))) {
+                        if (bstr_startswith0(lang, opts->sub_lang[n])) {
                             prio = 4; // matches the movie name + lang extension
+                            found_lang = opts->sub_lang[n];
                             break;
                         }
                     }
@@ -177,6 +173,7 @@ static void append_dir_subtitles(struct MPOpts *opts,
 
                 sub->priority = prio;
                 sub->fname    = subpath;
+                sub->lang     = found_lang;
             } else
                 talloc_free(subpath);
         }
@@ -217,9 +214,10 @@ static void filter_subidx(struct subfn **slist, int *nsub)
     }
 }
 
-char **find_text_subtitles(struct MPOpts *opts, const char *fname)
+// Return a list of subtitles found, sorted by priority.
+// Last element is terminated with a fname==NULL entry.
+struct subfn *find_text_subtitles(struct MPOpts *opts, const char *fname)
 {
-    char **subnames = NULL;
     struct subfn *slist = talloc_array_ptrtype(NULL, slist, 1);
     int n = 0;
 
@@ -249,10 +247,8 @@ char **find_text_subtitles(struct MPOpts *opts, const char *fname)
     // Sort subs by priority and append them
     qsort(slist, n, sizeof(*slist), compare_sub_priority);
 
-    subnames = talloc_array_ptrtype(NULL, subnames, n);
-    for (int i = 0; i < n; i++)
-        subnames[i] = talloc_strdup(subnames, slist[i].fname);
+    struct subfn z = {0};
+    MP_TARRAY_APPEND(NULL, slist, n, z);
 
-    talloc_free(slist);
-    return subnames;
+    return slist;
 }

sub/find_subfiles.h

@@ -21,6 +21,12 @@
 
 struct MPOpts;
 
-char **find_text_subtitles(struct MPOpts *opts, const char *fname);
+struct subfn {
+    int priority;
+    char *fname;
+    char *lang;
+};
+
+struct subfn *find_text_subtitles(struct MPOpts *opts, const char *fname);
 
 #endif /* MPLAYER_FINDFILES_H */