/****************************************************************************
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** General Public License version 3.0 as published by the Free Software
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****************************************************************************/

#include "qnumeric.h"
#include "qnumeric_p.h"

QT_BEGIN_NAMESPACE

#ifdef QT_NO_STL
/*!
    Returns true if the double \a {d} is equivalent to infinity.
*/
Q_CORE_EXPORT bool qIsInf(double d)
{
    uchar *ch = (uchar *)&d;
#ifdef QT_ARMFPA
    return (ch[3] & 0x7f) == 0x7f && ch[2] == 0xf0;
#else
    if (QSysInfo::ByteOrder == QSysInfo::BigEndian) {
        return (ch[0] & 0x7f) == 0x7f && ch[1] == 0xf0;
    } else {
        return (ch[7] & 0x7f) == 0x7f && ch[6] == 0xf0;
    }
#endif
}

/*!
    Returns true if the double \a {d} is not a number (NaN).
*/
Q_CORE_EXPORT bool qIsNaN(double d)
{
    uchar *ch = (uchar *)&d;
#ifdef QT_ARMFPA
    return (ch[3] & 0x7f) == 0x7f && ch[2] > 0xf0;
#else
    if (QSysInfo::ByteOrder == QSysInfo::BigEndian) {
        return (ch[0] & 0x7f) == 0x7f && ch[1] > 0xf0;
    } else {
        return (ch[7] & 0x7f) == 0x7f && ch[6] > 0xf0;
    }
#endif
}

/*!
    Returns true if the double \a {d} is a finite number.
*/
Q_CORE_EXPORT bool qIsFinite(double d)
{
    uchar *ch = (uchar *)&d;
#ifdef QT_ARMFPA
    return (ch[3] & 0x7f) != 0x7f || (ch[2] & 0xf0) != 0xf0;
#else
    if (QSysInfo::ByteOrder == QSysInfo::BigEndian) {
        return (ch[0] & 0x7f) != 0x7f || (ch[1] & 0xf0) != 0xf0;
    } else {
        return (ch[7] & 0x7f) != 0x7f || (ch[6] & 0xf0) != 0xf0;
    }
#endif
}

/*!
    Returns true if the float \a {f} is equivalent to infinity.
*/
Q_CORE_EXPORT bool qIsInf(float f)
{
    uchar *ch = (uchar *)&f;
    if (QSysInfo::ByteOrder == QSysInfo::BigEndian) {
        return (ch[0] & 0x7f) == 0x7f && ch[1] == 0x80;
    } else {
        return (ch[3] & 0x7f) == 0x7f && ch[2] == 0x80;
    }
}

/*!
    Returns true if the float \a {f} is not a number (NaN).
*/
Q_CORE_EXPORT bool qIsNaN(float f)
{
    uchar *ch = (uchar *)&f;
    if (QSysInfo::ByteOrder == QSysInfo::BigEndian) {
        return (ch[0] & 0x7f) == 0x7f && ch[1] > 0x80;
    } else {
        return (ch[3] & 0x7f) == 0x7f && ch[2] > 0x80;
    }
}

/*!
    Returns true if the float \a {f} is a finite number.
*/
Q_CORE_EXPORT bool qIsFinite(float f)
{
    uchar *ch = (uchar *)&f;
    if (QSysInfo::ByteOrder == QSysInfo::BigEndian) {
        return (ch[0] & 0x7f) != 0x7f || (ch[1] & 0x80) != 0x80;
    } else {
        return (ch[3] & 0x7f) != 0x7f || (ch[2] & 0x80) != 0x80;
    }
}
#endif // QT_NO_STL

/*!
    Returns the bit pattern of a signalling NaN as a double.
*/
Q_CORE_EXPORT double qSNaN() { return qt_snan(); }

/*!
    Returns the bit pattern of a quiet NaN as a double.
*/
Q_CORE_EXPORT double qQNaN() { return qt_qnan(); }

/*!
    Returns the bit pattern for an infinite number as a double.
*/
Q_CORE_EXPORT double qInf() { return qt_inf(); }

QT_END_NAMESPACE