//
// FPEnvironment.h
//
// Library: Foundation
// Package: Core
// Module:  FPEnvironment
//
// Definitions of class FPEnvironment.
//
// Copyright (c) 2004-2006, Applied Informatics Software Engineering GmbH.
// and Contributors.
//
// SPDX-License-Identifier:	BSL-1.0
//


#ifndef Foundation_FPEnvironment_INCLUDED
#define Foundation_FPEnvironment_INCLUDED


#include "Poco/Foundation.h"


#if defined(POCO_NO_FPENVIRONMENT)
/// #include "Poco/FPEnvironment_DUMMY.h"
#elif defined(__osf__)
#    include "Poco/FPEnvironment_DEC.h"
#elif defined(sun) || defined(__sun)
#    include "Poco/FPEnvironment_SUN.h"
#elif defined(POCO_OS_FAMILY_UNIX)
#    include "Poco/FPEnvironment_C99.h"
#else
#    include "Poco/FPEnvironment_DUMMY.h"
#endif


namespace Poco
{


class Foundation_API FPEnvironment : private FPEnvironmentImpl
/// Instances of this class can be used to save
/// and later restore the current floating
/// point environment (consisting of rounding
/// mode and floating-point flags).
/// The class also provides various static
/// methods to query certain properties
/// of a floating-point number.
{
public:
    enum RoundingMode
    {
        FP_ROUND_DOWNWARD = FP_ROUND_DOWNWARD_IMPL,
        FP_ROUND_UPWARD = FP_ROUND_UPWARD_IMPL,
        FP_ROUND_TONEAREST = FP_ROUND_TONEAREST_IMPL,
        FP_ROUND_TOWARDZERO = FP_ROUND_TOWARDZERO_IMPL
    };

    enum Flag
    {
        FP_DIVIDE_BY_ZERO = FP_DIVIDE_BY_ZERO_IMPL,
        FP_INEXACT = FP_INEXACT_IMPL,
        FP_OVERFLOW = FP_OVERFLOW_IMPL,
        FP_UNDERFLOW = FP_UNDERFLOW_IMPL,
        FP_INVALID = FP_INVALID_IMPL
    };

    FPEnvironment();
    /// Standard constructor.
    /// Remembers the current environment.

    FPEnvironment(RoundingMode mode);
    /// Remembers the current environment and
    /// sets the given rounding mode.

    FPEnvironment(const FPEnvironment & env);
    /// Copy constructor.

    ~FPEnvironment();
    /// Restores the previous environment (unless
    /// keepCurrent() has been called previously)

    FPEnvironment & operator=(const FPEnvironment & env);
    /// Assignment operator

    void keepCurrent();
    /// Keep the current environment even after
    /// destroying the FPEnvironment object.

    static void clearFlags();
    /// Resets all flags.

    static bool isFlag(Flag flag);
    /// Returns true iff the given flag is set.

    static void setRoundingMode(RoundingMode mode);
    /// Sets the rounding mode.

    static RoundingMode getRoundingMode();
    /// Returns the current rounding mode.

    static bool isInfinite(float value);
    static bool isInfinite(double value);
    static bool isInfinite(long double value);
    /// Returns true iff the given number is infinite.

    static bool isNaN(float value);
    static bool isNaN(double value);
    static bool isNaN(long double value);
    /// Returns true iff the given number is NaN.

    static float copySign(float target, float source);
    static double copySign(double target, double source);
    static long double copySign(long double target, long double source);
    /// Copies the sign from source to target.
};


//
// For convenience, we provide a shorter name for
// the FPEnvironment class.
//
typedef FPEnvironment FPE;


//
// inline's
//
inline bool FPEnvironment::isFlag(Flag flag)
{
    return isFlagImpl(FlagImpl(flag));
}


inline void FPEnvironment::setRoundingMode(RoundingMode mode)
{
    setRoundingModeImpl(RoundingModeImpl(mode));
}


inline FPEnvironment::RoundingMode FPEnvironment::getRoundingMode()
{
    return RoundingMode(getRoundingModeImpl());
}


inline bool FPEnvironment::isInfinite(float value)
{
    return isInfiniteImpl(value);
}


inline bool FPEnvironment::isInfinite(double value)
{
    return isInfiniteImpl(value);
}


inline bool FPEnvironment::isInfinite(long double value)
{
    return isInfiniteImpl(value);
}


inline bool FPEnvironment::isNaN(float value)
{
    return isNaNImpl(value);
}


inline bool FPEnvironment::isNaN(double value)
{
    return isNaNImpl(value);
}


inline bool FPEnvironment::isNaN(long double value)
{
    return isNaNImpl(value);
}


inline float FPEnvironment::copySign(float target, float source)
{
    return copySignImpl(target, source);
}


inline double FPEnvironment::copySign(double target, double source)
{
    return copySignImpl(target, source);
}


inline long double FPEnvironment::copySign(long double target, long double source)
{
    return copySignImpl(target, source);
}


} // namespace Poco


#endif // Foundation_FPEnvironment_INCLUDED