common/include/QtCore/qflags.h

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#include <QtCore/qglobal.h>

#ifndef QFLAGS_H
#define QFLAGS_H

#include <QtCore/qtypeinfo.h>
#include <QtCore/qtypetraits.h>

#ifdef Q_COMPILER_INITIALIZER_LISTS
#include <initializer_list>
#endif

QT_BEGIN_NAMESPACE

class QFlag
{
    int i;
public:
    Q_DECL_CONSTEXPR inline QFlag(int ai) Q_DECL_NOTHROW : i(ai) {}
    Q_DECL_CONSTEXPR inline operator int() const Q_DECL_NOTHROW { return i; }

#if !defined(Q_CC_MSVC)
    // Microsoft Visual Studio has buggy behavior when it comes to
    // unsigned enums: even if the enum is unsigned, the enum tags are
    // always signed
#  if !defined(__LP64__) && !defined(Q_QDOC)
    Q_DECL_CONSTEXPR inline QFlag(long ai) Q_DECL_NOTHROW : i(int(ai)) {}
    Q_DECL_CONSTEXPR inline QFlag(ulong ai) Q_DECL_NOTHROW : i(int(long(ai))) {}
#  endif
    Q_DECL_CONSTEXPR inline QFlag(uint ai) Q_DECL_NOTHROW : i(int(ai)) {}
    Q_DECL_CONSTEXPR inline QFlag(short ai) Q_DECL_NOTHROW : i(int(ai)) {}
    Q_DECL_CONSTEXPR inline QFlag(ushort ai) Q_DECL_NOTHROW : i(int(uint(ai))) {}
    Q_DECL_CONSTEXPR inline operator uint() const Q_DECL_NOTHROW { return uint(i); }
#endif
};
Q_DECLARE_TYPEINFO(QFlag, Q_PRIMITIVE_TYPE);

class QIncompatibleFlag
{
    int i;
public:
    Q_DECL_CONSTEXPR inline explicit QIncompatibleFlag(int i) Q_DECL_NOTHROW;
    Q_DECL_CONSTEXPR inline operator int() const Q_DECL_NOTHROW { return i; }
};
Q_DECLARE_TYPEINFO(QIncompatibleFlag, Q_PRIMITIVE_TYPE);

Q_DECL_CONSTEXPR inline QIncompatibleFlag::QIncompatibleFlag(int ai) Q_DECL_NOTHROW : i(ai) {}


#ifndef Q_NO_TYPESAFE_FLAGS

template<typename Enum>
class QFlags
{
    Q_STATIC_ASSERT_X((sizeof(Enum) <= sizeof(int)),
                      "QFlags uses an int as storage, so an enum with underlying "
                      "long long will overflow.");
    struct Private;
    typedef int (Private::*Zero);
public:
#if defined(Q_CC_MSVC) || defined(Q_QDOC)
    // see above for MSVC
    // the definition below is too complex for qdoc
    typedef int Int;
#else
    typedef typename QtPrivate::if_<
            QtPrivate::is_unsigned<Enum>::value,
            unsigned int,
            signed int
        >::type Int;
#endif
    typedef Enum enum_type;
    // compiler-generated copy/move ctor/assignment operators are fine!
#ifdef Q_QDOC
    inline QFlags(const QFlags &other);
    inline QFlags &operator=(const QFlags &other);
#endif
    Q_DECL_CONSTEXPR inline QFlags(Enum f) Q_DECL_NOTHROW : i(Int(f)) {}
    Q_DECL_CONSTEXPR inline QFlags(Zero = 0) Q_DECL_NOTHROW : i(0) {}
    Q_DECL_CONSTEXPR inline QFlags(QFlag f) Q_DECL_NOTHROW : i(f) {}

#ifdef Q_COMPILER_INITIALIZER_LISTS
    Q_DECL_CONSTEXPR inline QFlags(std::initializer_list<Enum> flags) Q_DECL_NOTHROW
        : i(initializer_list_helper(flags.begin(), flags.end())) {}
#endif

    Q_DECL_RELAXED_CONSTEXPR inline QFlags &operator&=(int mask) Q_DECL_NOTHROW { i &= mask; return *this; }
    Q_DECL_RELAXED_CONSTEXPR inline QFlags &operator&=(uint mask) Q_DECL_NOTHROW { i &= mask; return *this; }
    Q_DECL_RELAXED_CONSTEXPR inline QFlags &operator&=(Enum mask) Q_DECL_NOTHROW { i &= Int(mask); return *this; }
    Q_DECL_RELAXED_CONSTEXPR inline QFlags &operator|=(QFlags f) Q_DECL_NOTHROW { i |= f.i; return *this; }
    Q_DECL_RELAXED_CONSTEXPR inline QFlags &operator|=(Enum f) Q_DECL_NOTHROW { i |= Int(f); return *this; }
    Q_DECL_RELAXED_CONSTEXPR inline QFlags &operator^=(QFlags f) Q_DECL_NOTHROW { i ^= f.i; return *this; }
    Q_DECL_RELAXED_CONSTEXPR inline QFlags &operator^=(Enum f) Q_DECL_NOTHROW { i ^= Int(f); return *this; }

    Q_DECL_CONSTEXPR inline operator Int() const Q_DECL_NOTHROW { return i; }

    Q_DECL_CONSTEXPR inline QFlags operator|(QFlags f) const Q_DECL_NOTHROW { return QFlags(QFlag(i | f.i)); }
    Q_DECL_CONSTEXPR inline QFlags operator|(Enum f) const Q_DECL_NOTHROW { return QFlags(QFlag(i | Int(f))); }
    Q_DECL_CONSTEXPR inline QFlags operator^(QFlags f) const Q_DECL_NOTHROW { return QFlags(QFlag(i ^ f.i)); }
    Q_DECL_CONSTEXPR inline QFlags operator^(Enum f) const Q_DECL_NOTHROW { return QFlags(QFlag(i ^ Int(f))); }
    Q_DECL_CONSTEXPR inline QFlags operator&(int mask) const Q_DECL_NOTHROW { return QFlags(QFlag(i & mask)); }
    Q_DECL_CONSTEXPR inline QFlags operator&(uint mask) const Q_DECL_NOTHROW { return QFlags(QFlag(i & mask)); }
    Q_DECL_CONSTEXPR inline QFlags operator&(Enum f) const Q_DECL_NOTHROW { return QFlags(QFlag(i & Int(f))); }
    Q_DECL_CONSTEXPR inline QFlags operator~() const Q_DECL_NOTHROW { return QFlags(QFlag(~i)); }

    Q_DECL_CONSTEXPR inline bool operator!() const Q_DECL_NOTHROW { return !i; }

    Q_DECL_CONSTEXPR inline bool testFlag(Enum f) const Q_DECL_NOTHROW { return (i & Int(f)) == Int(f) && (Int(f) != 0 || i == Int(f) ); }
private:
#ifdef Q_COMPILER_INITIALIZER_LISTS
    Q_DECL_CONSTEXPR static inline Int initializer_list_helper(typename std::initializer_list<Enum>::const_iterator it,
                                                               typename std::initializer_list<Enum>::const_iterator end)
    Q_DECL_NOTHROW
    {
        return (it == end ? Int(0) : (Int(*it) | initializer_list_helper(it + 1, end)));
    }
#endif

    Int i;
};

#define Q_DECLARE_FLAGS(Flags, Enum)\
typedef QFlags<Enum> Flags;

#define Q_DECLARE_INCOMPATIBLE_FLAGS(Flags) \
Q_DECL_CONSTEXPR inline QIncompatibleFlag operator|(Flags::enum_type f1, int f2) Q_DECL_NOTHROW \
{ return QIncompatibleFlag(int(f1) | f2); }

#define Q_DECLARE_OPERATORS_FOR_FLAGS(Flags) \
Q_DECL_CONSTEXPR inline QFlags<Flags::enum_type> operator|(Flags::enum_type f1, Flags::enum_type f2) Q_DECL_NOTHROW \
{ return QFlags<Flags::enum_type>(f1) | f2; } \
Q_DECL_CONSTEXPR inline QFlags<Flags::enum_type> operator|(Flags::enum_type f1, QFlags<Flags::enum_type> f2) Q_DECL_NOTHROW \
{ return f2 | f1; } Q_DECLARE_INCOMPATIBLE_FLAGS(Flags)


#else /* Q_NO_TYPESAFE_FLAGS */

#define Q_DECLARE_FLAGS(Flags, Enum)\
typedef uint Flags;
#define Q_DECLARE_OPERATORS_FOR_FLAGS(Flags)

#endif /* Q_NO_TYPESAFE_FLAGS */

QT_END_NAMESPACE

#endif // QFLAGS_H