70 lines
1.4 KiB
C++
70 lines
1.4 KiB
C++
// SPDX-License-Identifier: GPL-2.0-or-later
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// Copyright The Music Player Daemon Project
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#ifndef MPD_STATE_FILE_HXX
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#define MPD_STATE_FILE_HXX
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#include "StateFileConfig.hxx"
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#include "event/FarTimerEvent.hxx"
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#include "config.h"
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#include <string>
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struct Partition;
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class OutputStream;
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class BufferedOutputStream;
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class StateFile final {
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const StateFileConfig config;
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const std::string path_utf8;
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FarTimerEvent timer_event;
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Partition &partition;
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/**
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* These version numbers determine whether we need to save the state
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* file. If nothing has changed, we won't let the hard drive spin up.
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*/
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unsigned prev_volume_version = 0, prev_output_version = 0,
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prev_playlist_version = 0;
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#ifdef ENABLE_DATABASE
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unsigned prev_storage_version = 0;
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#endif
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public:
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StateFile(StateFileConfig &&_config,
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Partition &partition, EventLoop &loop);
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void Read();
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void Write();
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/**
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* Schedules a write if MPD's state was modified.
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*/
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void CheckModified() noexcept;
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private:
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void Write(OutputStream &os);
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void Write(BufferedOutputStream &os);
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/**
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* Save the current state versions for use with IsModified().
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*/
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void RememberVersions() noexcept;
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/**
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* Check if MPD's state was modified since the last
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* RememberVersions() call.
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*/
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[[gnu::pure]]
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bool IsModified() const noexcept;
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/* callback for #timer_event */
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void OnTimeout() noexcept;
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};
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#endif /* STATE_FILE_H */
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