output/Thread: move code to new class AudioOutputSource

src/output/Source.hxx

@@ -0,0 +1,160 @@
+/*
+ * 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 AUDIO_OUTPUT_SOURCE_HXX
+#define AUDIO_OUTPUT_SOURCE_HXX
+
+#include "check.h"
+#include "Compiler.h"
+#include "SharedPipeConsumer.hxx"
+#include "AudioFormat.hxx"
+#include "ReplayGainMode.hxx"
+#include "pcm/PcmBuffer.hxx"
+#include "pcm/PcmDither.hxx"
+
+#include <assert.h>
+
+template<typename T> struct ConstBuffer;
+struct MusicChunk;
+class Filter;
+class PreparedFilter;
+
+/**
+ * Source of audio data to be played by an #AudioOutput.  It receives
+ * #MusicChunk instances from a #MusicPipe (via #SharedPipeConsumer).
+ * It applies configured filters, ReplayGain and returns plain PCM
+ * data.
+ */
+class AudioOutputSource {
+	/**
+	 * The audio_format in which audio data is received from the
+	 * player thread (which in turn receives it from the decoder).
+	 */
+	AudioFormat in_audio_format = AudioFormat::Undefined();
+
+	ReplayGainMode replay_gain_mode = ReplayGainMode::OFF;
+
+	/**
+	 * A reference to the #MusicPipe and the current position.
+	 */
+	SharedPipeConsumer pipe;
+
+	/**
+	 * The serial number of the last replay gain info.  0 means no
+	 * replay gain info was available.
+	 */
+	unsigned replay_gain_serial = 0;
+
+	/**
+	 * The serial number of the last replay gain info by the
+	 * "other" chunk during cross-fading.
+	 */
+	unsigned other_replay_gain_serial = 0;
+
+	/**
+	 * The replay_gain_filter_plugin instance of this audio
+	 * output.
+	 */
+	Filter *replay_gain_filter_instance = nullptr;
+
+	/**
+	 * The replay_gain_filter_plugin instance of this audio
+	 * output, to be applied to the second chunk during
+	 * cross-fading.
+	 */
+	Filter *other_replay_gain_filter_instance = nullptr;
+
+	/**
+	 * The buffer used to allocate the cross-fading result.
+	 */
+	PcmBuffer cross_fade_buffer;
+
+	/**
+	 * The dithering state for cross-fading two streams.
+	 */
+	PcmDither cross_fade_dither;
+
+	/**
+	 * The filter object of this audio output.  This is an
+	 * instance of chain_filter_plugin.
+	 */
+	Filter *filter_instance = nullptr;
+
+public:
+	void SetReplayGainMode(ReplayGainMode _mode) {
+		replay_gain_mode = _mode;
+	}
+
+	bool IsOpen() const {
+		return in_audio_format.IsDefined();
+	}
+
+	const AudioFormat &GetInputAudioFormat() const {
+		return in_audio_format;
+	}
+
+	AudioFormat Open(AudioFormat audio_format, const MusicPipe &_pipe,
+			 PreparedFilter *prepared_replay_gain_filter,
+			 PreparedFilter *prepared_other_replay_gain_filter,
+			 PreparedFilter *prepared_filter);
+
+	void Close();
+
+	void Cancel() {
+		pipe.Cancel();
+	}
+
+	const MusicChunk *Get() {
+		assert(IsOpen());
+
+		return pipe.Get();
+	}
+
+	void Consume(const MusicChunk &chunk) {
+		assert(IsOpen());
+
+		pipe.Consume(chunk);
+	}
+
+	bool IsChunkConsumed(const MusicChunk &chunk) const {
+		assert(IsOpen());
+
+		return pipe.IsConsumed(chunk);
+	}
+
+	void ClearTailChunk(const MusicChunk &chunk) {
+		pipe.ClearTail(chunk);
+	}
+
+	ConstBuffer<void> FilterChunk(const MusicChunk &chunk);
+
+private:
+	void OpenFilter(AudioFormat audio_format,
+			PreparedFilter *prepared_replay_gain_filter,
+			PreparedFilter *prepared_other_replay_gain_filter,
+			PreparedFilter *prepared_filter);
+
+	void CloseFilter();
+
+	ConstBuffer<void> GetChunkData(const MusicChunk &chunk,
+				       Filter *replay_gain_filter,
+				       unsigned *replay_gain_serial_p);
+};
+
+#endif