decoder/Internal: rename struct Decoder to class DecoderBridge

src/decoder/Bridge.hxx

@@ -0,0 +1,143 @@
+/*
+ * 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_DECODER_BRIDGE_HXX
+#define MPD_DECODER_BRIDGE_HXX
+
+#include "Client.hxx"
+#include "ReplayGainInfo.hxx"
+
+#include <exception>
+
+class PcmConvert;
+struct MusicChunk;
+struct DecoderControl;
+struct Tag;
+
+/**
+ * A bridge between the #DecoderClient interface and the MPD core
+ * (#DecoderControl, #MusicPipe etc.).
+ */
+class DecoderBridge final : public DecoderClient {
+public:
+	DecoderControl &dc;
+
+	/**
+	 * For converting input data to the configured audio format.
+	 * nullptr means no conversion necessary.
+	 */
+	PcmConvert *convert = nullptr;
+
+	/**
+	 * The time stamp of the next data chunk, in seconds.
+	 */
+	double timestamp = 0;
+
+	/**
+	 * Is the initial seek (to the start position of the sub-song)
+	 * pending, or has it been performed already?
+	 */
+	bool initial_seek_pending;
+
+	/**
+	 * Is the initial seek currently running?  During this time,
+	 * the decoder command is SEEK.  This flag is set by
+	 * decoder_get_virtual_command(), when the virtual SEEK
+	 * command is generated for the first time.
+	 */
+	bool initial_seek_running = false;
+
+	/**
+	 * This flag is set by GetSeekTime(), and checked by
+	 * CommandFinished().  It is used to clean up after seeking.
+	 */
+	bool seeking = false;
+
+	/**
+	 * The tag from the song object.  This is only used for local
+	 * files, because we expect the stream server to send us a new
+	 * tag each time we play it.
+	 */
+	Tag *song_tag;
+
+	/** the last tag received from the stream */
+	Tag *stream_tag = nullptr;
+
+	/** the last tag received from the decoder plugin */
+	Tag *decoder_tag = nullptr;
+
+	/** the chunk currently being written to */
+	MusicChunk *current_chunk = nullptr;
+
+	ReplayGainInfo replay_gain_info;
+
+	/**
+	 * A positive serial number for checking if replay gain info
+	 * has changed since the last check.
+	 */
+	unsigned replay_gain_serial = 0;
+
+	/**
+	 * An error has occurred (in DecoderAPI.cxx), and the plugin
+	 * will be asked to stop.
+	 */
+	std::exception_ptr error;
+
+	DecoderBridge(DecoderControl &_dc, bool _initial_seek_pending,
+		      Tag *_tag)
+		:dc(_dc),
+		 initial_seek_pending(_initial_seek_pending),
+		 song_tag(_tag) {}
+
+	~DecoderBridge();
+
+	/**
+	 * Returns the current chunk the decoder writes to, or allocates a new
+	 * chunk if there is none.
+	 *
+	 * @return the chunk, or NULL if we have received a decoder command
+	 */
+	MusicChunk *GetChunk();
+
+	/**
+	 * Flushes the current chunk.
+	 *
+	 * Caller must not lock the #DecoderControl object.
+	 */
+	void FlushChunk();
+
+	/* virtual methods from DecoderClient */
+	void Ready(AudioFormat audio_format,
+		   bool seekable, SignedSongTime duration) override;
+	DecoderCommand GetCommand() override;
+	void CommandFinished() override;
+	SongTime GetSeekTime() override;
+	uint64_t GetSeekFrame() override;
+	void SeekError() override;
+	InputStreamPtr OpenUri(const char *uri) override;
+	void SubmitTimestamp(double t) override;
+	DecoderCommand SubmitData(InputStream *is,
+				  const void *data, size_t length,
+				  uint16_t kbit_rate) override;
+	DecoderCommand SubmitTag(InputStream *is, Tag &&tag) override ;
+	void SubmitReplayGain(const ReplayGainInfo *replay_gain_info) override;
+	void SubmitMixRamp(MixRampInfo &&mix_ramp) override;
+};
+
+#endif