db/simple: pass DatabaseSelection to WalkMount()

This passes the new `sort` and `window` attributes to the mounted
database.

src/db/plugins/simple/Directory.cxx

@@ -27,6 +27,7 @@
 #include "db/Uri.hxx"
 #include "db/DatabaseLock.hxx"
 #include "db/Interface.hxx"
+#include "db/Selection.hxx"
 #include "song/Filter.hxx"
 #include "lib/icu/Collate.hxx"
 #include "fs/Traits.hxx"
@@ -227,7 +228,7 @@ Directory::Walk(bool recursive, const SongFilter *filter,
 		   call will lock it again */
 		const ScopeDatabaseUnlock unlock;
 		WalkMount(GetPath(), *mounted_database,
-			  "", recursive, filter,
+			  "", DatabaseSelection("", recursive, filter),
 			  visit_directory, visit_song,
 			  visit_playlist);
 		return;

src/db/plugins/simple/Mount.cxx

@@ -66,7 +66,8 @@ PrefixVisitPlaylist(const char *base, const VisitPlaylist &visit_playlist,
 
 void
 WalkMount(const char *base, const Database &db,
-	  const char* uri, bool recursive, const SongFilter *filter,
+	  const char *uri,
+	  const DatabaseSelection &old_selection,
 	  const VisitDirectory &visit_directory, const VisitSong &visit_song,
 	  const VisitPlaylist &visit_playlist)
 {
@@ -87,16 +88,19 @@ WalkMount(const char *base, const Database &db,
 		vp = std::bind(PrefixVisitPlaylist,
 			       base, std::ref(visit_playlist), _1, _2);
 
+	DatabaseSelection selection(old_selection);
+	selection.uri = uri;
+
 	SongFilter prefix_filter;
 
-	if (base != nullptr && filter != nullptr) {
+	if (base != nullptr && selection.filter != nullptr) {
 		/* if the SongFilter contains a LOCATE_TAG_BASE_TYPE
 		   item, copy the SongFilter and drop the mount point
 		   from the filter, because the mounted database
 		   doesn't know its own location within MPD's VFS */
-		prefix_filter = filter->WithoutBasePrefix(base);
-		filter = &prefix_filter;
+		prefix_filter = selection.filter->WithoutBasePrefix(base);
+		selection.filter = &prefix_filter;
 	}
 
-	db.Visit(DatabaseSelection(uri, recursive, filter), vd, vs, vp);
+	db.Visit(selection, vd, vs, vp);
 }

src/db/plugins/simple/Mount.hxx

@@ -23,11 +23,12 @@
 #include "db/Visitor.hxx"
 
 class Database;
-class SongFilter;
+struct DatabaseSelection;
 
 void
 WalkMount(const char *base, const Database &db,
-	  const char* uri, bool recursive, const SongFilter *filter,
+	  const char *uri,
+	  const DatabaseSelection &old_selection,
 	  const VisitDirectory &visit_directory, const VisitSong &visit_song,
 	  const VisitPlaylist &visit_playlist);
 

src/db/plugins/simple/SimpleDatabasePlugin.cxx

@@ -280,8 +280,8 @@ SimpleDatabase::Visit(const DatabaseSelection &selection,
 		protect.unlock();
 
 		WalkMount(r.directory->GetPath(), *(r.directory->mounted_database),
-			(r.uri == nullptr)?"":r.uri, selection.recursive, selection.filter,
-			visit_directory, visit_song, visit_playlist);
+			  (r.uri == nullptr)?"":r.uri, selection,
+			  visit_directory, visit_song, visit_playlist);
 
 		return;
 	}