ImfStdIO.h

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//
// SPDX-License-Identifier: BSD-3-Clause
// Copyright (c) Contributors to the OpenEXR Project.
//

#ifndef INCLUDED_IMF_STD_IO_H
#define INCLUDED_IMF_STD_IO_H

//-----------------------------------------------------------------------------
//
//      Low-level file input and output for OpenEXR
//      based on C++ standard iostreams.
//
//-----------------------------------------------------------------------------

#include "ImfExport.h"
#include "ImfNamespace.h"

#include "ImfIO.h"

#include <fstream>
#include <sstream>

OPENEXR_IMF_INTERNAL_NAMESPACE_HEADER_ENTER

//-------------------------------------------
// class StdIFStream -- an implementation of
// class OPENEXR_IMF_INTERNAL_NAMESPACE::IStream based on class std::ifstream
//-------------------------------------------

class IMF_EXPORT_TYPE StdIFStream
    : public OPENEXR_IMF_INTERNAL_NAMESPACE::IStream
{
public:
    //-------------------------------------------------------
    // A constructor that opens the file with the given name.
    // The destructor will close the file.
    //-------------------------------------------------------

    IMF_EXPORT StdIFStream (const char fileName[]);

    //---------------------------------------------------------
    // A constructor that uses a std::ifstream that has already
    // been opened by the caller.  The StdIFStream's destructor
    // will not close the std::ifstream.
    //---------------------------------------------------------

    IMF_EXPORT StdIFStream (std::ifstream& is, const char fileName[]);

    IMF_EXPORT virtual ~StdIFStream ();
    StdIFStream (const StdIFStream&)            = delete;
    StdIFStream (StdIFStream&&)                 = delete;
    StdIFStream& operator= (const StdIFStream&) = delete;
    StdIFStream& operator= (StdIFStream&&)      = delete;

    IMF_EXPORT virtual bool     read (char c[/*n*/], int n);
    IMF_EXPORT virtual uint64_t tellg ();
    IMF_EXPORT virtual void     seekg (uint64_t pos);
    IMF_EXPORT virtual void     clear ();

private:
    std::ifstream* _is;
    bool           _deleteStream;
};

//------------------------------------------------
// class StdISStream -- an implementation of class
// OPENEXR_IMF_INTERNAL_NAMESPACE::IStream, based on class std::istringstream
//------------------------------------------------

class IMF_EXPORT_TYPE StdISStream
    : public OPENEXR_IMF_INTERNAL_NAMESPACE::IStream
{
public:
    IMF_EXPORT StdISStream ();
    IMF_EXPORT ~StdISStream ();
    StdISStream (const StdISStream&)            = delete;
    StdISStream (StdISStream&&)                 = delete;
    StdISStream& operator= (const StdISStream&) = delete;
    StdISStream& operator= (StdISStream&&)      = delete;

    IMF_EXPORT virtual bool     read (char c[/*n*/], int n);
    IMF_EXPORT virtual uint64_t tellg ();
    IMF_EXPORT virtual void     seekg (uint64_t pos);
    IMF_EXPORT virtual void     clear ();

    IMF_EXPORT std::string str () const;

    IMF_EXPORT void str (const std::string& s);

private:
    std::istringstream _is;
};

//-------------------------------------------
// class StdOFStream -- an implementation of
// class OPENEXR_IMF_INTERNAL_NAMESPACE::OStream based on class std::ofstream
//-------------------------------------------

class IMF_EXPORT_TYPE StdOFStream
    : public OPENEXR_IMF_INTERNAL_NAMESPACE::OStream
{
public:
    //-------------------------------------------------------
    // A constructor that opens the file with the given name.
    // The destructor will close the file.
    //-------------------------------------------------------

    IMF_EXPORT StdOFStream (const char fileName[]);

    //---------------------------------------------------------
    // A constructor that uses a std::ofstream that has already
    // been opened by the caller.  The StdOFStream's destructor
    // will not close the std::ofstream.
    //---------------------------------------------------------

    IMF_EXPORT StdOFStream (std::ofstream& os, const char fileName[]);

    IMF_EXPORT virtual ~StdOFStream ();
    StdOFStream (const StdOFStream&)            = delete;
    StdOFStream (StdOFStream&&)                 = delete;
    StdOFStream& operator= (const StdOFStream&) = delete;
    StdOFStream& operator= (StdOFStream&&)      = delete;

    IMF_EXPORT virtual void     write (const char c[/*n*/], int n);
    IMF_EXPORT virtual uint64_t tellp ();
    IMF_EXPORT virtual void     seekp (uint64_t pos);

private:
    std::ofstream* _os;
    bool           _deleteStream;
};

//------------------------------------------------
// class StdOSStream -- an implementation of class
// OPENEXR_IMF_INTERNAL_NAMESPACE::OStream, based on class std::ostringstream
//------------------------------------------------

class IMF_EXPORT_TYPE StdOSStream
    : public OPENEXR_IMF_INTERNAL_NAMESPACE::OStream
{
public:
    IMF_EXPORT StdOSStream ();
    IMF_EXPORT ~StdOSStream ();
    StdOSStream (const StdOSStream&)            = delete;
    StdOSStream (StdOSStream&&)                 = delete;
    StdOSStream& operator= (const StdOSStream&) = delete;
    StdOSStream& operator= (StdOSStream&&)      = delete;

    IMF_EXPORT virtual void     write (const char c[/*n*/], int n);
    IMF_EXPORT virtual uint64_t tellp ();
    IMF_EXPORT virtual void     seekp (uint64_t pos);

    IMF_EXPORT std::string str () const;

private:
    std::ostringstream _os;
};

OPENEXR_IMF_INTERNAL_NAMESPACE_HEADER_EXIT

#endif