spxout.h

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/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
/*                                                                           */
/*                  This file is part of the class library                   */
/*       SoPlex --- the Sequential object-oriented simPlex.                  */
/*                                                                           */
/*    Copyright (C) 1996-2019 Konrad-Zuse-Zentrum                            */
/*                            fuer Informationstechnik Berlin                */
/*                                                                           */
/*  SoPlex is distributed under the terms of the ZIB Academic Licence.       */
/*                                                                           */
/*  You should have received a copy of the ZIB Academic License              */
/*  along with SoPlex; see the file COPYING. If not email to soplex@zib.de.  */
/*                                                                           */
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

/**@file  spxout.h
 * @brief Wrapper for different output streams and verbosity levels.
 */
#ifndef _SPXOUT_H_
#define _SPXOUT_H_

#include <iostream>
#include <iomanip>
#include <assert.h>

#include "soplex/spxdefines.h"

// ----------------------------------------------------------------------
//    class SPxOut
// ----------------------------------------------------------------------

namespace soplex
{

/**@class SPxOut
   @ingroup Elementary

   @brief Wrapper for several output streams.
   A verbosity level is used to decide which stream to use and whether to
   really print a given message. Regardless of whether the verbosity level
   is set via a manipulator or via the member function, it is persistent
   until a new value is set.

   Most ostream member functions are not provided here; use the corresponding
   stream manipulators (e.g., @c setprecision()) instead. These are passed on
   to the <em>current</em> ostream, which is chosen according to the verbosity
   level. In particular, this means that the first element in an output stream
   should always be the verbosity. For instance, use
   @code
      spxout << verb( SPxOut::WARNING ) << std::setw( 15 ) << 42 << std::endl;
   @endcode
   or
   @code
      spxout.setVerbosity( SPxOut::WARNING );
      spxout << std::setw( 15 ) << 42 << std::endl;
   @endcode
   instead of
   @code
      spxout << std::setw( 15 ) << verb( SPxOut::WARNING ) << 42 << std::endl;
   @endcode
   in order to make sure that @c std::setw( 15 ) is applied to the warning stream.
*/
class SPxOut
{
public:


   //-----------------------------------
   /**@name Output control types */
   //@{
   /// Verbosity level
   typedef enum
   {
      // Note: the implementation uses the fact that ERROR == 0
      // and that the verbosity levels are subsequent numbers.
      // If you change this, change the implementation as well.
      ERROR    = 0,
      WARNING  = 1,
      DEBUG    = 2,
      INFO1    = 3,
      INFO2    = 4,
      INFO3    = 5
   } Verbosity;

   /// helper struct for the output operator
   struct struct_Verbosity
   {
      /// verbosity level
      Verbosity v_;
   };
   //@}

   //-----------------------------------
   /**@name Construction / destruction */
   //@{
   /// constructor
   SPxOut();
   /// destructor
   virtual ~SPxOut();
   /// copy constructor
   SPxOut(const SPxOut&);
   /// assignment operator
   SPxOut& operator=(const SPxOut&);
   //@}

   //-----------------------------------
   /**@name Verbosity */
   //@{
   ///
   virtual void
   setVerbosity(const Verbosity& v)
   {
      m_verbosity = v;
   }
   ///
   inline Verbosity
   getVerbosity()
   const
   {
      return m_verbosity;
   }

   //@}

   //----------------------------------------
   /**@name Wrappers for the current stream */
   //@{
   ///
   inline bool good() const
   {
      return getCurrentStream().good();
   }
   ///
   inline bool operator !() const
   {
      return ! getCurrentStream();
   }
   ///
   inline std::streamsize precision() const
   {
      return getCurrentStream().precision();
   }
   //@}

   //-----------------------------------
   /**@name Getting / setting streams */
   //@{
   /// Sets the stream for the specified verbosity level.
   virtual void
   setStream(const Verbosity& verbosity,
             std::ostream&   stream)
   {
      m_streams[ verbosity ] = &stream;
   }
   /// Returns the stream for the specified verbosity level.
   inline std::ostream&
   getStream(const Verbosity& verbosity)
   const
   {
      return *(m_streams[ verbosity ]);
   }
   /// Returns the stream for the current verbosity.
   inline std::ostream&
   getCurrentStream()
   const
   {
      return getStream(getVerbosity());
   }

   /// Sets the precision of the stream to 16 and the floatfield to scientifix.
   static inline void setScientific(std::ostream& stream, int precision = 8)
   {
      stream << std::setprecision(precision) << std::scientific;
   }

   /// Sets the precision of the stream to 8 and the floatfield to fixed.
   static inline void setFixed(std::ostream& stream, int precision = 8)
   {
      stream << std::setprecision(precision) << std::fixed;
   }
   //@}

private:

   //-----------------------------------
   /**@name Private data */
   //@{
   /// verbosity level
   Verbosity               m_verbosity;
   /// array of pointers to internal streams, indexed by verbosity level
   std::ostream**          m_streams;
   //@}
};

// ---------------------------------------------------------
//    Manipulators
// ---------------------------------------------------------


//-------------------------------------------
/**@name Verbosity manipulator
    Manipulators are implemented in a similar way as done for @c setw(),
    @c setprecision(), etc. in the standard library file iomanip. For
    instance, the non-member function \ref verb() "verb(v)" returns a
    struct struct_Severity which contains only the verbosity level.
    Calling
    @code
         SPxOut spxout;
         spxout << verb( SPxOut::ERROR ) << "This is an error!" << std::endl;
    @endcode
    passes such a struct to the output operator defined below, which
    extracts the verbosity level from the struct and passes it to the
    member function SPxOut::setVerbosity().
*/
//@{
/// manipulator to be used in an output statement
inline SPxOut::struct_Verbosity
verb(const SPxOut::Verbosity&  v)
{
   SPxOut::struct_Verbosity verbosity;
   verbosity.v_ = v;
   return verbosity;
}

/// output operator with verbosity level struct
inline SPxOut&
operator<< (SPxOut& stream,
            const SPxOut::struct_Verbosity&  verbosity)
{
   stream.setVerbosity(verbosity.v_);
   return stream;
}
//@}

//--------------------------------------------------------
/**@name Output of standard manipulators and other types
 *
 * We have to define an output operator for many kinds of numeric
 * types here because they can all be more or less casted into each
 * other. When using only a template type, it is not clear what the
 * compiler makes out of it (according to lint).
 */
//@{
///
#define PASS_TO_CURRENT_OSTREAM( t ) \
      _spxout.getCurrentStream() << t; \
      return _spxout;

/// Passes instances of type \p Type to the current stream.
#define DEFINE_OUTPUT_OPERATOR( Type ) \
   inline SPxOut& \
   operator<< ( SPxOut& _spxout, Type t ) \
   { PASS_TO_CURRENT_OSTREAM( t ) }

DEFINE_OUTPUT_OPERATOR(long)
DEFINE_OUTPUT_OPERATOR(unsigned long)
DEFINE_OUTPUT_OPERATOR(bool)
DEFINE_OUTPUT_OPERATOR(short)
DEFINE_OUTPUT_OPERATOR(unsigned short)
DEFINE_OUTPUT_OPERATOR(int)
DEFINE_OUTPUT_OPERATOR(unsigned int)
DEFINE_OUTPUT_OPERATOR(double)
DEFINE_OUTPUT_OPERATOR(float)
DEFINE_OUTPUT_OPERATOR(long double)
DEFINE_OUTPUT_OPERATOR(const void*)

/// Passes standard manipulators without arguments, like @c std::endl
/// or @c std::ios::right to the current stream.
inline SPxOut&
operator<< (SPxOut&       _spxout,
            std::ostream & (*manip)(std::ostream&))
{
   PASS_TO_CURRENT_OSTREAM(manip)
}

//lint -e{818} (pointer could be made const; this is ok.)
/// Passes everything else to the current stream. In particular,
/// this includes structs corresponding to manipulators with arguments,
/// such as the struct @c _Setw for the @c setw() manipulator.
template< typename T >
inline SPxOut&
operator<< (SPxOut& _spxout, T  t)
{
   PASS_TO_CURRENT_OSTREAM(t)
}
//@}

}  // namespace soplex

#endif // _SPXOUT_H_