disk_reader.h

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/*
 * Copyright (C) 2017-2019 Robin Gareus <robin@gareus.org>
 * Copyright (C) 2017 Paul Davis <paul@linuxaudiosystems.com>
 *
 * 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 _ardour_disk_reader_h_
#define _ardour_disk_reader_h_
 
#include <atomic>
 
#include <optional>
 
#include "evoral/Curve.h"
 
#include "ardour/disk_io.h"
#include "ardour/midi_buffer.h"
#include "ardour/midi_state_tracker.h"
 
namespace ARDOUR
{
class Playlist;
class AudioPlaylist;
class MidiPlaylist;
 
template <typename T> class MidiRingBuffer;
 
class /*LIBARDOUR_API*/ DiskReader : public DiskIOProcessor
{
public:
        LIBARDOUR_API DiskReader (Session&, Track&, std::string const& name, Temporal::TimeDomainProvider const &, DiskIOProcessor::Flag f = DiskIOProcessor::Flag (0));
        LIBARDOUR_API ~DiskReader ();
 
        LIBARDOUR_API bool set_name (std::string const& str);
 
        LIBARDOUR_API std::string display_name () const;
 
        LIBARDOUR_API static samplecnt_t chunk_samples ()
        {
                return _chunk_samples;
        }
 
        LIBARDOUR_API static void set_chunk_samples (samplecnt_t n)
        {
                _chunk_samples = n;
        }
 
        LIBARDOUR_API static samplecnt_t default_chunk_samples ();
 
        LIBARDOUR_API void run (BufferSet& /*bufs*/, samplepos_t /*start_sample*/, samplepos_t /*end_sample*/, double speed, pframes_t /*nframes*/, bool /*result_required*/);
        LIBARDOUR_API void realtime_handle_transport_stopped ();
        LIBARDOUR_API void realtime_locate (bool);
        LIBARDOUR_API void midi_chase (samplepos_t spos);
        LIBARDOUR_API void clear_midi_chase ();
        LIBARDOUR_API bool overwrite_existing_buffers ();
        LIBARDOUR_API void set_pending_overwrite (OverwriteReason);
        LIBARDOUR_API void set_loop (Location*);
 
        LIBARDOUR_API int set_state (const XMLNode&, int version);
 
        PBD::Signal<void()> AlignmentStyleChanged;
 
        LIBARDOUR_API float buffer_load () const;
 
        LIBARDOUR_API void move_processor_automation (std::weak_ptr<Processor>, std::list<Temporal::RangeMove> const&);
 
        /* called by the Butler in a non-realtime context as part of its normal
         * buffer refill loop (not due to transport-mechanism requests like
         * locate)
         */
        LIBARDOUR_API int do_refill ();
 
        int do_refill_with_alloc (bool partial_fill, bool reverse);
 
        LIBARDOUR_API bool pending_overwrite () const;
 
        /* Working buffers for do_refill (butler thread) */
        LIBARDOUR_API static void allocate_working_buffers ();
        LIBARDOUR_API static void free_working_buffers ();
 
        LIBARDOUR_API void adjust_buffering ();
 
        LIBARDOUR_API bool can_internal_playback_seek (sampleoffset_t distance);
        LIBARDOUR_API void internal_playback_seek (sampleoffset_t distance);
        LIBARDOUR_API int  seek (samplepos_t sample, bool complete_refill = false);
 
        LIBARDOUR_API static PBD::Signal<void()> Underrun;
 
        LIBARDOUR_API void playlist_modified ();
        LIBARDOUR_API void reset_tracker ();
 
        LIBARDOUR_API bool declick_in_progress () const;
 
        LIBARDOUR_API void set_need_midi_catchup (bool);
 
        /* inc/dec variants MUST be called as part of the process call tree, before any
         * disk readers are invoked. We use it when the session needs the
         * transport (and thus effective read position for DiskReaders) to keep
         * advancing as part of syncing up with a transport master, but we
         * don't want any actual disk output yet because we are still not
         * synced.
         */
        LIBARDOUR_API static void inc_no_disk_output ();
        LIBARDOUR_API static void dec_no_disk_output ();
        LIBARDOUR_API static bool no_disk_output ()
        {
                return _no_disk_output.load ();
        }
        LIBARDOUR_API static void reset_loop_declick (Location*, samplecnt_t sample_rate);
        LIBARDOUR_API static void alloc_loop_declick (samplecnt_t sample_rate);
 
protected:
        friend class Track;
        friend class MidiTrack;
 
        struct ReaderChannelInfo : public DiskIOProcessor::ChannelInfo {
                LIBARDOUR_API ReaderChannelInfo (samplecnt_t buffer_size, samplecnt_t preloop_size)
                        : DiskIOProcessor::ChannelInfo (buffer_size)
                        , pre_loop_buffer (0)
                        , pre_loop_buffer_size (0)
                        , initialized (false)
                {
                        resize (buffer_size);
                }
 
                LIBARDOUR_API ~ReaderChannelInfo ()
                {
                        delete[] pre_loop_buffer;
                }
 
                LIBARDOUR_API void resize (samplecnt_t);
                LIBARDOUR_API void resize_preloop (samplecnt_t);
 
                Sample*     pre_loop_buffer;
                samplecnt_t pre_loop_buffer_size;
                bool        initialized;
        };
 
        LIBARDOUR_API XMLNode& state () const;
 
        LIBARDOUR_API void resolve_tracker (Evoral::EventSink<samplepos_t>& buffer, samplepos_t time);
 
        LIBARDOUR_API int  use_playlist (DataType, std::shared_ptr<Playlist>);
        LIBARDOUR_API void playlist_ranges_moved (std::list<Temporal::RangeMove> const&, bool);
 
        LIBARDOUR_API int add_channel_to (std::shared_ptr<ChannelList>, uint32_t how_many);
 
        class DeclickAmp
        {
        public:
                DeclickAmp (samplecnt_t sample_rate);
 
                void apply_gain (AudioBuffer& buf, samplecnt_t n_samples, const float target, sampleoffset_t buffer_offset = 0);
 
                float gain () const
                {
                        return _g;
                }
                void set_gain (float g)
                {
                        _g = g;
                }
 
        private:
                float _a;
                float _l;
                float _g;
        };
 
        class Declicker
        {
        public:
                Declicker ();
                ~Declicker ();
 
                void alloc (samplecnt_t sr, bool fadein, bool linear);
 
                void run (Sample* buf, samplepos_t start, samplepos_t end);
                void reset (samplepos_t start, samplepos_t end, bool fadein, samplecnt_t sr);
 
                samplepos_t fade_start;
                samplepos_t fade_end;
                samplecnt_t fade_length;
                Sample*     vec;
        };
 
private:
        samplepos_t    overwrite_sample;
        sampleoffset_t overwrite_offset;
        samplepos_t    new_file_sample;
        bool           run_must_resolve;
        IOChange       input_change_pending;
        samplepos_t    file_sample[DataType::num_types];
 
        mutable std::atomic<OverwriteReason> _pending_overwrite;
 
        DeclickAmp            _declick_amp;
        sampleoffset_t        _declick_offs;
        bool                  _declick_enabled;
        MidiNoteTracker      _tracker;
        MidiNoteTracker      _locate_tracker;
        std::optional<bool> _last_read_reversed;
        std::optional<bool> _last_read_loop;
 
        static samplecnt_t _chunk_samples;
 
        static std::atomic<int> _no_disk_output;
 
        static Declicker   loop_declick_in;
        static Declicker   loop_declick_out;
        static samplecnt_t loop_fade_length;
 
        samplecnt_t audio_read (Sample*      sum_buffer,
                                Sample*      mixdown_buffer,
                                float*       gain_buffer,
                                samplepos_t& start, samplecnt_t cnt,
                                ReaderChannelInfo* rci,
                                int                channel,
                                bool               reversed);
 
        static thread_local Sample* _sum_buffer;
        static thread_local Sample* _mixdown_buffer;
        static thread_local gain_t* _gain_buffer;
 
        int refill (Sample* sum_buffer, Sample* mixdown_buffer, float* gain_buffer, samplecnt_t fill_level, bool reversed);
        int refill_audio (Sample* sum_buffer, Sample* mixdown_buffer, float* gain_buffer, samplecnt_t fill_level, bool reversed);
 
        sampleoffset_t calculate_playback_distance (pframes_t);
 
        RTMidiBuffer* rt_midibuffer ();
 
        void get_midi_playback (MidiBuffer& dst, samplepos_t start_sample, samplepos_t end_sample, MonitorState, BufferSet&, double speed, samplecnt_t distance);
        void maybe_xfade_loop (Sample*, samplepos_t read_start, samplepos_t read_end, ReaderChannelInfo*);
 
        void configuration_changed ();
 
        bool overwrite_existing_audio ();
        bool overwrite_existing_midi ();
 
        samplepos_t last_refill_loop_start;
        void setup_preloop_buffer ();
 
        bool _midi_catchup;
        bool _need_midi_catchup;
};
 
} // namespace ARDOUR
 
#endif /* _ardour_disk_reader_h_ */