Sort playlists ignoring extension. (#15836)

"Sony - PlayStation 2" sorts before "Sony - PlayStation" because when
the menu sorts, it includes the `.lpl` extension, and space comes
before period.

libretro-common/include/lists/dir_list.h

@@ -85,6 +85,15 @@ bool dir_list_initialize(struct string_list *list,
  **/
 void dir_list_sort(struct string_list *list, bool dir_first);
 
+/**
+ * dir_list_sort_ignore_ext:
+ * @list      : pointer to the directory listing.
+ * @dir_first : move the directories in the listing to the top?
+ *
+ * Sorts a directory listing. File extensions are ignored.
+ **/
+void dir_list_sort_ignore_ext(struct string_list *list, bool dir_first);
+
 /**
  * dir_list_free:
  * @list : pointer to the directory listing

libretro-common/lists/dir_list.c

@@ -46,6 +46,22 @@ static int qstrcmp_plain(const void *a_, const void *b_)
    return strcasecmp(a->data, b->data);
 }
 
+static int qstrcmp_plain_noext(const void *a_, const void *b_)
+{
+   const struct string_list_elem *a = (const struct string_list_elem*)a_;
+   const struct string_list_elem *b = (const struct string_list_elem*)b_;
+
+   const char *ext_a = path_get_extension(a->data);
+   size_t l_a = string_is_empty(ext_a) ? strlen(a->data) : (ext_a - a->data - 1);
+   const char *ext_b = path_get_extension(b->data);
+   size_t l_b = string_is_empty(ext_b) ? strlen(b->data) : (ext_b - b->data - 1);
+
+   int rv = strncasecmp(a->data, b->data, MIN(l_a, l_b));
+   if (rv == 0 && l_a != l_b)
+       return (int)(l_a - l_b);
+   return rv;
+}
+
 static int qstrcmp_dir(const void *a_, const void *b_)
 {
    const struct string_list_elem *a = (const struct string_list_elem*)a_;
@@ -59,6 +75,19 @@ static int qstrcmp_dir(const void *a_, const void *b_)
    return strcasecmp(a->data, b->data);
 }
 
+static int qstrcmp_dir_noext(const void *a_, const void *b_)
+{
+   const struct string_list_elem *a = (const struct string_list_elem*)a_;
+   const struct string_list_elem *b = (const struct string_list_elem*)b_;
+   int a_type = a->attr.i;
+   int b_type = b->attr.i;
+
+   /* Sort directories before files. */
+   if (a_type != b_type)
+      return b_type - a_type;
+   return qstrcmp_plain_noext(a, b);
+}
+
 /**
  * dir_list_sort:
  * @list      : pointer to the directory listing.
@@ -73,6 +102,20 @@ void dir_list_sort(struct string_list *list, bool dir_first)
             dir_first ? qstrcmp_dir : qstrcmp_plain);
 }
 
+/**
+ * dir_list_sort_ignore_ext:
+ * @list      : pointer to the directory listing.
+ * @dir_first : move the directories in the listing to the top?
+ *
+ * Sorts a directory listing. File extensions are ignored.
+ **/
+void dir_list_sort_ignore_ext(struct string_list *list, bool dir_first)
+{
+   if (list)
+      qsort(list->elems, list->size, sizeof(struct string_list_elem),
+            dir_first ? qstrcmp_dir_noext : qstrcmp_plain_noext);
+}
+
 /**
  * dir_list_free:
  * @list : pointer to the directory listing

menu/menu_displaylist.c

@@ -4152,7 +4152,7 @@ static unsigned menu_displaylist_parse_playlists(
 
    content_count = count;
 
-   dir_list_sort(&str_list, true);
+   dir_list_sort_ignore_ext(&str_list, true);
 
    list_size = str_list.size;