decoder/flac: move FlacIOHandle.?xx to lib/xiph/

src/lib/xiph/FlacIOHandle.hxx

@@ -0,0 +1,45 @@
+/*
+ * Copyright 2003-2017 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifndef MPD_FLAC_IO_HANDLE_HXX
+#define MPD_FLAC_IO_HANDLE_HXX
+
+#include "Compiler.h"
+#include "input/InputStream.hxx"
+
+#include <FLAC/callback.h>
+
+extern const FLAC__IOCallbacks flac_io_callbacks;
+extern const FLAC__IOCallbacks flac_io_callbacks_seekable;
+
+static inline FLAC__IOHandle
+ToFlacIOHandle(InputStream &is)
+{
+	return (FLAC__IOHandle)&is;
+}
+
+static inline const FLAC__IOCallbacks &
+GetFlacIOCallbacks(const InputStream &is)
+{
+	return is.IsSeekable()
+		? flac_io_callbacks_seekable
+		: flac_io_callbacks;
+}
+
+#endif