encoder/{vorbis,opus}: move common code to class OggEncoder

src/encoder/plugins/OggEncoder.hxx

@@ -0,0 +1,59 @@
+/*
+ * Copyright 2003-2016 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_OGG_ENCODER_HXX
+#define MPD_OGG_ENCODER_HXX
+
+#include "config.h"
+#include "../EncoderAPI.hxx"
+#include "lib/xiph/OggStream.hxx"
+#include "lib/xiph/OggSerial.hxx"
+
+#include <ogg/ogg.h>
+
+/**
+ * An abstract base class which contains code common to all encoders
+ * with Ogg container output.
+ */
+class OggEncoder : public Encoder {
+protected:
+	OggStream stream;
+
+public:
+	OggEncoder(bool _implements_tag)
+		:Encoder(_implements_tag) {
+		stream.Initialize(GenerateOggSerial());
+	}
+
+	~OggEncoder() override {
+		stream.Deinitialize();
+	}
+
+	/* virtual methods from class Encoder */
+	bool Flush(Error &) override {
+		stream.Flush();
+		return true;
+	}
+
+	size_t Read(void *dest, size_t length) override {
+		return stream.PageOut(dest, length);
+	}
+};
+
+#endif