LCIORandomAccessMgr.h

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#ifndef SIO_LCIORandomAccessMgr_H
#define SIO_LCIORandomAccessMgr_H 1

// -- lcio headers
#include "SIO/LCIORandomAccess.h"
#include "SIO/LCIORecords.h"
#include "SIO/RunEventMap.h"

// -- sio headers
#include <sio/definitions.h>
#include <sio/buffer.h>

// -- std headers
#include <iostream>
#include <map>
#include <list>

namespace SIO {

  class LCIORandomAccessMgr ;
  class SIOIndexHandler ;
  class SIORandomAccessHandler ;

  std::ostream & operator<<(std::ostream& os, const LCIORandomAccessMgr& ra ) ;

  class LCIORandomAccessMgr {
    friend class SIOIndexHandler ;
    friend class SIORandomAccessHandler ;
    friend std::ostream & operator<<(std::ostream& os, const LCIORandomAccessMgr& ra ) ;

  public:
    typedef RunEvent::long64 long64 ;
    typedef std::list<std::shared_ptr<LCIORandomAccess>> LCIORandomAccessList ;

  public:
    LCIORandomAccessMgr() = default ;
    LCIORandomAccessMgr(const LCIORandomAccessMgr&) = delete ;
    LCIORandomAccessMgr& operator=(const LCIORandomAccessMgr&) = delete ;
    ~LCIORandomAccessMgr() = default ;

    long64 getPosition( const RunEvent& re ) {
      return _runEvtMap->getPosition( re  ) ;
    }

    void add(const RunEvent& re, long64 pos ) {
      _runEvtMap->add( re , pos ) ;
    }

    bool createEventMap( sio::ifstream &stream ) ;

    std::shared_ptr<RunEventMap> getEventMap() { return _runEvtMap ; }

    bool initAppend( sio::ifstream &stream ) ;


    void writeRandomAccessRecords( sio::ofstream &stream ) ;

    void clear() ;

    void seekStream( sio::ifstream &stream, long64 pos ) ;

  protected:

    std::shared_ptr<LCIORandomAccess> createFromEventMap() const ;

    void addLCIORandomAccess( std::shared_ptr<LCIORandomAccess> ra ) ;

    bool readLCIORandomAccessAt( sio::ifstream &stream , long64 pos) ;

    bool readLCIOIndexAt( sio::ifstream &stream , long64 pos) ;

    bool recreateEventMap( sio::ifstream &stream ) ;

    bool readLCIORandomAccess( sio::ifstream &stream ) ;

    bool readLCIOIndex( sio::ifstream &stream ) ;


    void createFileRecord() ;

    const std::shared_ptr<LCIORandomAccess> lastLCIORandomAccess() const {
      return (_list.empty() ?  0 : _list.back() )  ;
    }

  private:
    sio::buffer                        _rawBuffer { 32*sio::kbyte } ;

    sio::buffer                        _compressBuffer { 32*sio::kbyte } ;
    std::shared_ptr<RunEventMap>       _runEvtMap {std::make_shared<RunEventMap>()} ;
    LCIORandomAccessList               _list {} ;
    std::shared_ptr<LCIORandomAccess>  _fileRecord {nullptr} ;
  };
} // namespace
#endif