PlaylistStream: pass Path instance to playlist_open_path()

Convert filesystem charset to UTF-8 for playlist_list_open_uri().
This fixes one of many remaining charset bugs.

src/playlist/PlaylistMapper.cxx

@@ -41,7 +41,7 @@ playlist_open_in_playlist_dir(const char *uri, Mutex &mutex, Cond &cond)
 	if (path_fs.IsNull())
 		return nullptr;
 
-	return playlist_open_path(path_fs.c_str(), mutex, cond);
+	return playlist_open_path(path_fs, mutex, cond);
 }
 
 #ifdef ENABLE_DATABASE
@@ -61,7 +61,7 @@ playlist_open_in_storage(const char *uri, const Storage *storage,
 	{
 		const auto path = storage->MapFS(uri);
 		if (!path.IsNull())
-			return playlist_open_path(path.c_str(), mutex, cond);
+			return playlist_open_path(path, mutex, cond);
 	}
 
 	const auto uri2 = storage->MapUTF8(uri);

src/playlist/PlaylistStream.cxx

@@ -24,21 +24,23 @@
 #include "util/UriUtil.hxx"
 #include "util/Error.hxx"
 #include "input/InputStream.hxx"
+#include "fs/Path.hxx"
 #include "Log.hxx"
 
 #include <assert.h>
 
 static SongEnumerator *
-playlist_open_path_suffix(const char *path_fs, Mutex &mutex, Cond &cond)
+playlist_open_path_suffix(Path path, Mutex &mutex, Cond &cond)
 {
-	assert(path_fs != nullptr);
+	assert(!path.IsNull());
 
-	const char *suffix = uri_get_suffix(path_fs);
+	const char *suffix = uri_get_suffix(path.c_str());
 	if (suffix == nullptr || !playlist_suffix_supported(suffix))
 		return nullptr;
 
 	Error error;
-	InputStream *is = InputStream::OpenReady(path_fs, mutex, cond, error);
+	InputStream *is = InputStream::OpenReady(path.c_str(),
+						 mutex, cond, error);
 	if (is == nullptr) {
 		if (error.IsDefined())
 			LogError(error);
@@ -56,11 +58,16 @@ playlist_open_path_suffix(const char *path_fs, Mutex &mutex, Cond &cond)
 }
 
 SongEnumerator *
-playlist_open_path(const char *path_fs, Mutex &mutex, Cond &cond)
+playlist_open_path(Path path, Mutex &mutex, Cond &cond)
 {
-	auto playlist = playlist_list_open_uri(path_fs, mutex, cond);
+	assert(!path.IsNull());
+
+	const std::string uri_utf8 = path.ToUTF8();
+	auto playlist = !uri_utf8.empty()
+		? playlist_list_open_uri(uri_utf8.c_str(), mutex, cond)
+		: nullptr;
 	if (playlist == nullptr)
-		playlist = playlist_open_path_suffix(path_fs, mutex, cond);
+		playlist = playlist_open_path_suffix(path, mutex, cond);
 
 	return playlist;
 }

src/playlist/PlaylistStream.hxx

@@ -25,18 +25,19 @@
 class Mutex;
 class Cond;
 class SongEnumerator;
+class Path;
 
 /**
  * Opens a playlist from a local file.
  *
- * @param path_fs the path of the playlist file
+ * @param path the path of the playlist file
  * @param is_r on success, an input_stream object is returned here,
  * which must be closed after the playlist_provider object is freed
  * @return a playlist, or nullptr on error
  */
 gcc_nonnull_all
 SongEnumerator *
-playlist_open_path(const char *path_fs, Mutex &mutex, Cond &cond);
+playlist_open_path(Path path, Mutex &mutex, Cond &cond);
 
 gcc_nonnull_all
 SongEnumerator *