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** Copyright (C) 2017 Intel Corporation.
** Contact: https://www.qt.io/licensing/
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** This file is part of the QtCore module of the Qt Toolkit.
**
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** General Public License version 3 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL3 included in the
** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 3 requirements
** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
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** Alternatively, this file may be used under the terms of the GNU
** General Public License version 2.0 or (at your option) the GNU General
** Public license version 3 or any later version approved by the KDE Free
** Qt Foundation. The licenses are as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
** included in the packaging of this file. Please review the following
** information to ensure the GNU General Public License requirements will
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** https://www.gnu.org/licenses/gpl-3.0.html.
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** $QT_END_LICENSE$
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****************************************************************************/

#include "qplatformdefs.h"
#include "qstring.h"
#include "qlist.h"
#include "qdir.h"
#include "qdatetime.h"
#include "qoperatingsystemversion.h"
#include "qoperatingsystemversion_p.h"
#if defined(Q_OS_WIN) || defined(Q_OS_CYGWIN)
#  include "qoperatingsystemversion_win_p.h"
#  include "private/qwinregistry_p.h"
#endif // Q_OS_WIN || Q_OS_CYGWIN
#include <private/qlocale_tools_p.h>

#include <qmutex.h>
#include <QtCore/private/qlocking_p.h>

#include <stdlib.h>
#include <limits.h>
#include <stdarg.h>
#include <string.h>

#ifndef QT_NO_EXCEPTIONS
#  include <string>
#  include <exception>
#endif

#include <errno.h>
#if defined(Q_CC_MSVC)
#  include <crtdbg.h>
#endif

#ifdef Q_OS_WIN
#  include <qt_windows.h>
#endif

#if defined(Q_OS_VXWORKS) && defined(_WRS_KERNEL)
#  include <envLib.h>
#endif

#if defined(Q_OS_ANDROID) && !defined(Q_OS_ANDROID_EMBEDDED)
#include <private/qjni_p.h>
#endif

#if defined(Q_OS_SOLARIS)
#  include <sys/systeminfo.h>
#endif

#if defined(Q_OS_DARWIN) && __has_include(<IOKit/IOKitLib.h>)
#  include <IOKit/IOKitLib.h>
#  include <private/qcore_mac_p.h>
#endif

#ifdef Q_OS_UNIX
#include <sys/utsname.h>
#include <private/qcore_unix_p.h>
#endif

#ifdef Q_OS_BSD4
#include <sys/sysctl.h>
#endif

#if defined(Q_OS_INTEGRITY)
extern "C" {
    // Function mmap resides in libshm_client.a. To be able to link with it one needs
    // to define symbols 'shm_area_password' and 'shm_area_name', because the library
    // is meant to allow the application that links to it to use POSIX shared memory
    // without full system POSIX.
#  pragma weak shm_area_password
#  pragma weak shm_area_name
    char shm_area_password[] = "dummy";
    char shm_area_name[] = "dummy";
}
#endif

#include "archdetect.cpp"

#ifdef qFatal
// the qFatal in this file are just redirections from elsewhere, so
// don't capture any context again
#  undef qFatal
#endif

QT_BEGIN_NAMESPACE

// Statically check assumptions about the environment we're running
// in. The idea here is to error or warn if otherwise implicit Qt
// assumptions are not fulfilled on new hardware or compilers
// (if this list becomes too long, consider factoring into a separate file)
static_assert(UCHAR_MAX == 255, "Qt assumes that char is 8 bits");
static_assert(sizeof(int) == 4, "Qt assumes that int is 32 bits");
static_assert(QT_POINTER_SIZE == sizeof(void *), "QT_POINTER_SIZE defined incorrectly");
static_assert(sizeof(float) == 4, "Qt assumes that float is 32 bits");
static_assert(sizeof(char16_t) == 2, "Qt assumes that char16_t is 16 bits");
static_assert(sizeof(char32_t) == 4, "Qt assumes that char32_t is 32 bits");
#if defined(Q_OS_WIN)
static_assert(sizeof(wchar_t) == sizeof(char16_t));
#endif
static_assert(std::numeric_limits<int>::radix == 2,
                  "Qt assumes binary integers");
static_assert((std::numeric_limits<int>::max() + std::numeric_limits<int>::lowest()) == -1,
                  "Qt assumes two's complement integers");

// While we'd like to check for __STDC_IEC_559__, as per ISO/IEC 9899:2011
// Annex F (C11, normative for C++11), there are a few corner cases regarding
// denormals where GHS compiler is relying hardware behavior that is not IEC
// 559 compliant. So split the check in several subchecks.

// On GHC the compiler reports std::numeric_limits<float>::is_iec559 as false.
// This is all right according to our needs.
#if !defined(Q_CC_GHS)
static_assert(std::numeric_limits<float>::is_iec559,
                  "Qt assumes IEEE 754 floating point");
#endif

// Technically, presence of NaN and infinities are implied from the above check,
// but double checking our environment doesn't hurt...
static_assert(std::numeric_limits<float>::has_infinity &&
                  std::numeric_limits<float>::has_quiet_NaN &&
                  std::numeric_limits<float>::has_signaling_NaN,
                  "Qt assumes IEEE 754 floating point");

// is_iec559 checks for ISO/IEC/IEEE 60559:2011 (aka IEEE 754-2008) compliance,
// but that allows for a non-binary radix. We need to recheck that.
// Note how __STDC_IEC_559__ would instead check for IEC 60559:1989, aka
// ANSI/IEEE 754−1985, which specifically implies binary floating point numbers.
static_assert(std::numeric_limits<float>::radix == 2,
                  "Qt assumes binary IEEE 754 floating point");

// not required by the definition of size_t, but we depend on this
static_assert(sizeof(size_t) == sizeof(void *), "size_t and a pointer don't have the same size");
static_assert(sizeof(size_t) == sizeof(qsizetype)); // implied by the definition
static_assert((std::is_same<qsizetype, qptrdiff>::value));

/*!
    \class QFlag
    \inmodule QtCore
    \brief The QFlag class is a helper data type for QFlags.

    It is equivalent to a plain \c int, except with respect to
    function overloading and type conversions. You should never need
    to use this class in your applications.

    \sa QFlags
*/

/*!
    \fn QFlag::QFlag(int value)

    Constructs a QFlag object that stores the \a value.
*/

/*!
    \fn QFlag::QFlag(uint value)
    \since 5.3

    Constructs a QFlag object that stores the \a value.
*/

/*!
    \fn QFlag::QFlag(short value)
    \since 5.3

    Constructs a QFlag object that stores the \a value.
*/

/*!
    \fn QFlag::QFlag(ushort value)
    \since 5.3

    Constructs a QFlag object that stores the \a value.
*/

/*!
    \fn QFlag::operator int() const

    Returns the value stored by the QFlag object.
*/

/*!
    \fn QFlag::operator uint() const
    \since 5.3

    Returns the value stored by the QFlag object.
*/

/*!
    \class QFlags
    \inmodule QtCore
    \brief The QFlags class provides a type-safe way of storing
    OR-combinations of enum values.


    \ingroup tools

    The QFlags<Enum> class is a template class, where Enum is an enum
    type. QFlags is used throughout Qt for storing combinations of
    enum values.

    The traditional C++ approach for storing OR-combinations of enum
    values is to use an \c int or \c uint variable. The inconvenience
    with this approach is that there's no type checking at all; any
    enum value can be OR'd with any other enum value and passed on to
    a function that takes an \c int or \c uint.

    Qt uses QFlags to provide type safety. For example, the
    Qt::Alignment type is simply a typedef for
    QFlags<Qt::AlignmentFlag>. QLabel::setAlignment() takes a
    Qt::Alignment parameter, which means that any combination of
    Qt::AlignmentFlag values, or \c{{ }}, is legal:

    \snippet code/src_corelib_global_qglobal.cpp 0

    If you try to pass a value from another enum or just a plain
    integer other than 0, the compiler will report an error. If you
    need to cast integer values to flags in a untyped fashion, you can
    use the explicit QFlags constructor as cast operator.

    If you want to use QFlags for your own enum types, use
    the Q_DECLARE_FLAGS() and Q_DECLARE_OPERATORS_FOR_FLAGS().

    Example:

    \snippet code/src_corelib_global_qglobal.cpp 1

    You can then use the \c MyClass::Options type to store
    combinations of \c MyClass::Option values.

    \section1 Flags and the Meta-Object System

    The Q_DECLARE_FLAGS() macro does not expose the flags to the meta-object
    system, so they cannot be used by Qt Script or edited in Qt Designer.
    To make the flags available for these purposes, the Q_FLAG() macro must
    be used:

    \snippet code/src_corelib_global_qglobal.cpp meta-object flags

    \section1 Naming Convention

    A sensible naming convention for enum types and associated QFlags
    types is to give a singular name to the enum type (e.g., \c
    Option) and a plural name to the QFlags type (e.g., \c Options).
    When a singular name is desired for the QFlags type (e.g., \c
    Alignment), you can use \c Flag as the suffix for the enum type
    (e.g., \c AlignmentFlag).

    \sa QFlag
*/

/*!
    \typedef QFlags::Int
    \since 5.0

    Typedef for the integer type used for storage as well as for
    implicit conversion. Either \c int or \c{unsigned int}, depending
    on whether the enum's underlying type is signed or unsigned.
*/

/*!
    \typedef QFlags::enum_type

    Typedef for the Enum template type.
*/

/*!
    \fn template<typename Enum> QFlags<Enum>::QFlags(const QFlags &other)

    Constructs a copy of \a other.
*/

/*!
    \fn template <typename Enum> QFlags<Enum>::QFlags(Enum flags)

    Constructs a QFlags object storing the \a flags.
*/

/*!
    \fn template <typename Enum> QFlags<Enum>::QFlags()
    \since 5.15

    Constructs a QFlags object with no flags set.
*/

/*!
    \fn template <typename Enum> QFlags<Enum>::QFlags(QFlag flag)

    Constructs a QFlags object initialized with the integer \a flag.

    The QFlag type is a helper type. By using it here instead of \c
    int, we effectively ensure that arbitrary enum values cannot be
    cast to a QFlags, whereas untyped enum values (i.e., \c int
    values) can.
*/

/*!
    \fn template <typename Enum> QFlags<Enum>::QFlags(std::initializer_list<Enum> flags)
    \since 5.4

    Constructs a QFlags object initialized with all \a flags
    combined using the bitwise OR operator.

    \sa operator|=(), operator|()
*/

/*!
    \fn template <typename Enum> QFlags &QFlags<Enum>::operator=(const QFlags &other)

    Assigns \a other to this object and returns a reference to this
    object.
*/

/*!
    \fn template <typename Enum> QFlags &QFlags<Enum>::operator&=(int mask)

    Performs a bitwise AND operation with \a mask and stores the
    result in this QFlags object. Returns a reference to this object.

    \sa operator&(), operator|=(), operator^=()
*/

/*!
    \fn template <typename Enum> QFlags &QFlags<Enum>::operator&=(uint mask)

    \overload
*/

/*!
    \fn template <typename Enum> QFlags &QFlags<Enum>::operator&=(Enum mask)

    \overload
*/

/*!
    \fn template <typename Enum> QFlags &QFlags<Enum>::operator|=(QFlags other)

    Performs a bitwise OR operation with \a other and stores the
    result in this QFlags object. Returns a reference to this object.

    \sa operator|(), operator&=(), operator^=()
*/

/*!
    \fn template <typename Enum> QFlags &QFlags<Enum>::operator|=(Enum other)

    \overload
*/

/*!
    \fn template <typename Enum> QFlags &QFlags<Enum>::operator^=(QFlags other)

    Performs a bitwise XOR operation with \a other and stores the
    result in this QFlags object. Returns a reference to this object.

    \sa operator^(), operator&=(), operator|=()
*/

/*!
    \fn template <typename Enum> QFlags &QFlags<Enum>::operator^=(Enum other)

    \overload
*/

/*!
    \fn template <typename Enum> QFlags<Enum>::operator Int() const

    Returns the value stored in the QFlags object as an integer.

    \sa Int
*/

/*!
    \fn template <typename Enum> QFlags QFlags<Enum>::operator|(QFlags other) const

    Returns a QFlags object containing the result of the bitwise OR
    operation on this object and \a other.

    \sa operator|=(), operator^(), operator&(), operator~()
*/

/*!
    \fn template <typename Enum> QFlags QFlags<Enum>::operator|(Enum other) const

    \overload
*/

/*!
    \fn template <typename Enum> QFlags QFlags<Enum>::operator^(QFlags other) const

    Returns a QFlags object containing the result of the bitwise XOR
    operation on this object and \a other.

    \sa operator^=(), operator&(), operator|(), operator~()
*/

/*!
    \fn template <typename Enum> QFlags QFlags<Enum>::operator^(Enum other) const

    \overload
*/

/*!
    \fn template <typename Enum> QFlags QFlags<Enum>::operator&(int mask) const

    Returns a QFlags object containing the result of the bitwise AND
    operation on this object and \a mask.

    \sa operator&=(), operator|(), operator^(), operator~()
*/

/*!
    \fn template <typename Enum> QFlags QFlags<Enum>::operator&(uint mask) const

    \overload
*/

/*!
    \fn template <typename Enum> QFlags QFlags<Enum>::operator&(Enum mask) const

    \overload
*/

/*!
    \fn template <typename Enum> QFlags QFlags<Enum>::operator~() const

    Returns a QFlags object that contains the bitwise negation of
    this object.

    \sa operator&(), operator|(), operator^()
*/

/*!
    \fn template <typename Enum> bool QFlags<Enum>::operator!() const

    Returns \c true if no flag is set (i.e., if the value stored by the
    QFlags object is 0); otherwise returns \c false.
*/

/*!
    \fn template <typename Enum> bool QFlags<Enum>::testFlag(Enum flag) const
    \since 4.2

    Returns \c true if the flag \a flag is set, otherwise \c false.
*/

/*!
    \fn template <typename Enum> QFlags QFlags<Enum>::setFlag(Enum flag, bool on)
    \since 5.7

    Sets the flag \a flag if \a on is \c true or unsets it if
    \a on is \c false. Returns a reference to this object.
*/

/*!
  \macro Q_DISABLE_COPY(Class)
  \relates QObject

  Disables the use of copy constructors and assignment operators
  for the given \a Class.

  Instances of subclasses of QObject should not be thought of as
  values that can be copied or assigned, but as unique identities.
  This means that when you create your own subclass of QObject
  (director or indirect), you should \e not give it a copy constructor
  or an assignment operator.  However, it may not enough to simply
  omit them from your class, because, if you mistakenly write some code
  that requires a copy constructor or an assignment operator (it's easy
  to do), your compiler will thoughtfully create it for you. You must
  do more.

  The curious user will have seen that the Qt classes derived
  from QObject typically include this macro in a private section:

  \snippet code/src_corelib_global_qglobal.cpp 43

  It declares a copy constructor and an assignment operator in the
  private section, so that if you use them by mistake, the compiler
  will report an error.

  \snippet code/src_corelib_global_qglobal.cpp 44

  But even this might not catch absolutely every case. You might be
  tempted to do something like this:

  \snippet code/src_corelib_global_qglobal.cpp 45

  First of all, don't do that. Most compilers will generate code that
  uses the copy constructor, so the privacy violation error will be
  reported, but your C++ compiler is not required to generate code for
  this statement in a specific way. It could generate code using
  \e{neither} the copy constructor \e{nor} the assignment operator we
  made private. In that case, no error would be reported, but your
  application would probably crash when you called a member function
  of \c{w}.

  \sa Q_DISABLE_COPY_MOVE, Q_DISABLE_MOVE
*/

/*!
  \macro Q_DISABLE_MOVE(Class)
  \relates QObject

  Disables the use of move constructors and move assignment operators
  for the given \a Class.

  \sa Q_DISABLE_COPY, Q_DISABLE_COPY_MOVE
  \since 5.13
*/

/*!
  \macro Q_DISABLE_COPY_MOVE(Class)
  \relates QObject

  A convenience macro that disables the use of copy constructors, assignment
  operators, move constructors and move assignment operators for the given
  \a Class, combining Q_DISABLE_COPY and Q_DISABLE_MOVE.

  \sa Q_DISABLE_COPY, Q_DISABLE_MOVE
  \since 5.13
*/

/*!
    \macro Q_DECLARE_FLAGS(Flags, Enum)
    \relates QFlags

    The Q_DECLARE_FLAGS() macro expands to

    \snippet code/src_corelib_global_qglobal.cpp 2

    \a Enum is the name of an existing enum type, whereas \a Flags is
    the name of the QFlags<\e{Enum}> typedef.

    See the QFlags documentation for details.

    \sa Q_DECLARE_OPERATORS_FOR_FLAGS()
*/

/*!
    \macro Q_DECLARE_OPERATORS_FOR_FLAGS(Flags)
    \relates QFlags

    The Q_DECLARE_OPERATORS_FOR_FLAGS() macro declares global \c
    operator|() functions for \a Flags, which is of type QFlags<T>.

    See the QFlags documentation for details.

    \sa Q_DECLARE_FLAGS()
*/

/*!
    \headerfile <QtGlobal>
    \title Global Qt Declarations
    \ingroup funclists

    \brief The <QtGlobal> header file includes the fundamental global
    declarations. It is included by most other Qt header files.

    The global declarations include \l{types}, \l{functions} and
    \l{macros}.

    The type definitions are partly convenience definitions for basic
    types (some of which guarantee certain bit-sizes on all platforms
    supported by Qt), partly types related to Qt message handling. The
    functions are related to generating messages, Qt version handling
    and comparing and adjusting object values. And finally, some of
    the declared macros enable programmers to add compiler or platform
    specific code to their applications, while others are convenience
    macros for larger operations.

    \section1 Types

    The header file declares several type definitions that guarantee a
    specified bit-size on all platforms supported by Qt for various
    basic types, for example \l qint8 which is a signed char
    guaranteed to be 8-bit on all platforms supported by Qt. The
    header file also declares the \l qlonglong type definition for \c
    {long long int } (\c __int64 on Windows).

    Several convenience type definitions are declared: \l qreal for \c
    double or \c float, \l uchar for \c unsigned char, \l uint for \c unsigned
    int, \l ulong for \c unsigned long and \l ushort for \c unsigned
    short.

    Finally, the QtMsgType definition identifies the various messages
    that can be generated and sent to a Qt message handler;
    QtMessageHandler is a type definition for a pointer to a function with
    the signature
    \c {void myMessageHandler(QtMsgType, const QMessageLogContext &, const char *)}.
    QMessageLogContext class contains the line, file, and function the
    message was logged at. This information is created by the QMessageLogger
    class.

    \section1 Functions

    The <QtGlobal> header file contains several functions comparing
    and adjusting an object's value. These functions take a template
    type as argument: You can retrieve the absolute value of an object
    using the qAbs() function, and you can bound a given object's
    value by given minimum and maximum values using the qBound()
    function. You can retrieve the minimum and maximum of two given
    objects using qMin() and qMax() respectively. All these functions
    return a corresponding template type; the template types can be
    replaced by any other type.

    Example:

    \snippet code/src_corelib_global_qglobal.cpp 3

    <QtGlobal> also contains functions that generate messages from the
    given string argument: qDebug(), qInfo(), qWarning(), qCritical(),
    and qFatal(). These functions call the message handler
    with the given message.

    Example:

    \snippet code/src_corelib_global_qglobal.cpp 4

    The remaining functions are qRound() and qRound64(), which both
    accept a \c double or \c float value as their argument returning
    the value rounded up to the nearest integer and 64-bit integer
    respectively, the qInstallMessageHandler() function which installs
    the given QtMessageHandler, and the qVersion() function which
    returns the version number of Qt at run-time as a string.

    \section1 Macros

    The <QtGlobal> header file provides a range of macros (Q_CC_*)
    that are defined if the application is compiled using the
    specified platforms. For example, the Q_CC_SUN macro is defined if
    the application is compiled using Forte Developer, or Sun Studio
    C++.  The header file also declares a range of macros (Q_OS_*)
    that are defined for the specified platforms. For example,
    Q_OS_UNIX which is defined for the Unix-based systems.

    The purpose of these macros is to enable programmers to add
    compiler or platform specific code to their application.

    The remaining macros are convenience macros for larger operations:
    The QT_TR_NOOP(), QT_TRANSLATE_NOOP(), and QT_TRANSLATE_NOOP3()
    macros provide the possibility of marking strings for delayed
    translation. QT_TR_N_NOOP(), QT_TRANSLATE_N_NOOP(), and
    QT_TRANSLATE_N_NOOP3() are numerator dependent variants of these.
    The Q_ASSERT() and Q_ASSERT_X() enables warning messages of various
    level of refinement. The Q_FOREACH() and foreach() macros
    implement Qt's foreach loop.

    The Q_INT64_C() and Q_UINT64_C() macros wrap signed and unsigned
    64-bit integer literals in a platform-independent way. The
    Q_CHECK_PTR() macro prints a warning containing the source code's
    file name and line number, saying that the program ran out of
    memory, if the pointer is \nullptr. The qPrintable() and qUtf8Printable()
    macros represent an easy way of printing text.

    The QT_POINTER_SIZE macro expands to the size of a pointer in bytes.

    The macros QT_VERSION and QT_VERSION_STR expand to a numeric value
    or a string, respectively, that specifies the version of Qt that the
    application is compiled against.

    \sa <QtAlgorithms>, QSysInfo
*/

/*!
    \typedef qreal
    \relates <QtGlobal>

    Typedef for \c double unless Qt is configured with the
    \c{-qreal float} option.
*/

/*! \typedef uchar
    \relates <QtGlobal>

    Convenience typedef for \c{unsigned char}.
*/

/*! \typedef ushort
    \relates <QtGlobal>

    Convenience typedef for \c{unsigned short}.
*/

/*! \typedef uint
    \relates <QtGlobal>

    Convenience typedef for \c{unsigned int}.
*/

/*! \typedef ulong
    \relates <QtGlobal>

    Convenience typedef for \c{unsigned long}.
*/

/*! \typedef qint8
    \relates <QtGlobal>

    Typedef for \c{signed char}. This type is guaranteed to be 8-bit
    on all platforms supported by Qt.
*/

/*!
    \typedef quint8
    \relates <QtGlobal>

    Typedef for \c{unsigned char}. This type is guaranteed to
    be 8-bit on all platforms supported by Qt.
*/

/*! \typedef qint16
    \relates <QtGlobal>

    Typedef for \c{signed short}. This type is guaranteed to be
    16-bit on all platforms supported by Qt.
*/

/*!
    \typedef quint16
    \relates <QtGlobal>

    Typedef for \c{unsigned short}. This type is guaranteed to
    be 16-bit on all platforms supported by Qt.
*/

/*! \typedef qint32
    \relates <QtGlobal>

    Typedef for \c{signed int}. This type is guaranteed to be 32-bit
    on all platforms supported by Qt.
*/

/*!
    \typedef quint32
    \relates <QtGlobal>

    Typedef for \c{unsigned int}. This type is guaranteed to
    be 32-bit on all platforms supported by Qt.
*/

/*! \typedef qint64
    \relates <QtGlobal>

    Typedef for \c{long long int} (\c __int64 on Windows). This type
    is guaranteed to be 64-bit on all platforms supported by Qt.

    Literals of this type can be created using the Q_INT64_C() macro:

    \snippet code/src_corelib_global_qglobal.cpp 5

    \sa Q_INT64_C(), quint64, qlonglong
*/

/*!
    \typedef quint64
    \relates <QtGlobal>

    Typedef for \c{unsigned long long int} (\c{unsigned __int64} on
    Windows). This type is guaranteed to be 64-bit on all platforms
    supported by Qt.

    Literals of this type can be created using the Q_UINT64_C()
    macro:

    \snippet code/src_corelib_global_qglobal.cpp 6

    \sa Q_UINT64_C(), qint64, qulonglong
*/

/*!
    \typedef qintptr
    \relates <QtGlobal>

    Integral type for representing pointers in a signed integer (useful for
    hashing, etc.).

    Typedef for either qint32 or qint64. This type is guaranteed to
    be the same size as a pointer on all platforms supported by Qt. On
    a system with 32-bit pointers, qintptr is a typedef for qint32;
    on a system with 64-bit pointers, qintptr is a typedef for
    qint64.

    Note that qintptr is signed. Use quintptr for unsigned values.

    \sa qptrdiff, qint32, qint64
*/

/*!
    \typedef quintptr
    \relates <QtGlobal>

    Integral type for representing pointers in an unsigned integer (useful for
    hashing, etc.).

    Typedef for either quint32 or quint64. This type is guaranteed to
    be the same size as a pointer on all platforms supported by Qt. On
    a system with 32-bit pointers, quintptr is a typedef for quint32;
    on a system with 64-bit pointers, quintptr is a typedef for
    quint64.

    Note that quintptr is unsigned. Use qptrdiff for signed values.

    \sa qptrdiff, quint32, quint64
*/

/*!
    \typedef qptrdiff
    \relates <QtGlobal>

    Integral type for representing pointer differences.

    Typedef for either qint32 or qint64. This type is guaranteed to be
    the same size as a pointer on all platforms supported by Qt. On a
    system with 32-bit pointers, quintptr is a typedef for quint32; on
    a system with 64-bit pointers, quintptr is a typedef for quint64.

    Note that qptrdiff is signed. Use quintptr for unsigned values.

    \sa quintptr, qint32, qint64
*/

/*!
    \typedef qsizetype
    \relates <QtGlobal>
    \since 5.10

    Integral type providing Posix' \c ssize_t for all platforms.

    This type is guaranteed to be the same size as a \c size_t on all
    platforms supported by Qt.

    Note that qsizetype is signed. Use \c size_t for unsigned values.

    \sa qptrdiff
*/

/*!
    \enum QtMsgType
    \relates <QtGlobal>

    This enum describes the messages that can be sent to a message
    handler (QtMessageHandler). You can use the enum to identify and
    associate the various message types with the appropriate
    actions.

    \value QtDebugMsg
           A message generated by the qDebug() function.
    \value QtInfoMsg
           A message generated by the qInfo() function.
    \value QtWarningMsg
           A message generated by the qWarning() function.
    \value QtCriticalMsg
           A message generated by the qCritical() function.
    \value QtFatalMsg
           A message generated by the qFatal() function.
    \value QtSystemMsg

    \c QtInfoMsg was added in Qt 5.5.

    \sa QtMessageHandler, qInstallMessageHandler()
*/

/*! \typedef QFunctionPointer
    \relates <QtGlobal>

    This is a typedef for \c{void (*)()}, a pointer to a function that takes
    no arguments and returns void.
*/

/*! \macro qint64 Q_INT64_C(literal)
    \relates <QtGlobal>

    Wraps the signed 64-bit integer \a literal in a
    platform-independent way.

    Example:

    \snippet code/src_corelib_global_qglobal.cpp 8

    \sa qint64, Q_UINT64_C()
*/

/*! \macro quint64 Q_UINT64_C(literal)
    \relates <QtGlobal>

    Wraps the unsigned 64-bit integer \a literal in a
    platform-independent way.

    Example:

    \snippet code/src_corelib_global_qglobal.cpp 9

    \sa quint64, Q_INT64_C()
*/

/*! \typedef qlonglong
    \relates <QtGlobal>

    Typedef for \c{long long int} (\c __int64 on Windows). This is
    the same as \l qint64.

    \sa qulonglong, qint64
*/

/*!
    \typedef qulonglong
    \relates <QtGlobal>

    Typedef for \c{unsigned long long int} (\c{unsigned __int64} on
    Windows). This is the same as \l quint64.

    \sa quint64, qlonglong
*/

/*! \fn template <typename T> T qAbs(const T &t)
    \relates <QtGlobal>

    Compares \a t to the 0 of type T and returns the absolute
    value. Thus if T is \e {double}, then \a t is compared to
    \e{(double) 0}.

    Example:

    \snippet code/src_corelib_global_qglobal.cpp 10
*/

/*! \fn int qRound(double d)
    \relates <QtGlobal>

    Rounds \a d to the nearest integer.

    Rounds half away from zero (e.g. 0.5 -> 1, -0.5 -> -1).

    Example:

    \snippet code/src_corelib_global_qglobal.cpp 11A
*/

/*! \fn int qRound(float d)
    \relates <QtGlobal>

    Rounds \a d to the nearest integer.

    Rounds half away from zero (e.g. 0.5f -> 1, -0.5f -> -1).

    Example:

    \snippet code/src_corelib_global_qglobal.cpp 11B
*/

/*! \fn qint64 qRound64(double d)
    \relates <QtGlobal>

    Rounds \a d to the nearest 64-bit integer.

    Rounds half away from zero (e.g. 0.5 -> 1, -0.5 -> -1).

    Example:

    \snippet code/src_corelib_global_qglobal.cpp 12A
*/

/*! \fn qint64 qRound64(float d)
    \relates <QtGlobal>

    Rounds \a d to the nearest 64-bit integer.

    Rounds half away from zero (e.g. 0.5f -> 1, -0.5f -> -1).

    Example:

    \snippet code/src_corelib_global_qglobal.cpp 12B
*/

/*! \fn template <typename T> const T &qMin(const T &a, const T &b)
    \relates <QtGlobal>

    Returns the minimum of \a a and \a b.

    Example:

    \snippet code/src_corelib_global_qglobal.cpp 13

    \sa qMax(), qBound()
*/

/*! \fn template <typename T> const T &qMax(const T &a, const T &b)
    \relates <QtGlobal>

    Returns the maximum of \a a and \a b.

    Example:

    \snippet code/src_corelib_global_qglobal.cpp 14

    \sa qMin(), qBound()
*/

/*! \fn template <typename T> const T &qBound(const T &min, const T &val, const T &max)
    \relates <QtGlobal>

    Returns \a val bounded by \a min and \a max. This is equivalent
    to qMax(\a min, qMin(\a val, \a max)).

    Example:

    \snippet code/src_corelib_global_qglobal.cpp 15

    \sa qMin(), qMax()
*/

/*! \fn template <typename T> auto qOverload(T functionPointer)
    \relates <QtGlobal>
    \since 5.7

    Returns a pointer to an overloaded function. The template
    parameter is the list of the argument types of the function.
    \a functionPointer is the pointer to the (member) function:

    \snippet code/src_corelib_global_qglobal.cpp 52

    If a member function is also const-overloaded \l qConstOverload and
    \l qNonConstOverload need to be used.

    qOverload() requires C++14 enabled. In C++11-only code, the helper
    classes QOverload, QConstOverload, and QNonConstOverload can be used directly:

    \snippet code/src_corelib_global_qglobal.cpp 53

    \note Qt detects the necessary C++14 compiler support by way of the feature
    test recommendations from
    \l{https://isocpp.org/std/standing-documents/sd-6-sg10-feature-test-recommendations}
    {C++ Committee's Standing Document 6}.

    \sa qConstOverload(), qNonConstOverload(), {Differences between String-Based
    and Functor-Based Connections}
*/

/*! \fn template <typename T> auto qConstOverload(T memberFunctionPointer)
    \relates <QtGlobal>
    \since 5.7

    Returns the \a memberFunctionPointer pointer to a constant member function:

    \snippet code/src_corelib_global_qglobal.cpp 54

    \sa qOverload, qNonConstOverload, {Differences between String-Based
    and Functor-Based Connections}
*/

/*! \fn template <typename T> auto qNonConstOverload(T memberFunctionPointer)
    \relates <QtGlobal>
    \since 5.7

    Returns the \a memberFunctionPointer pointer to a non-constant member function:

    \snippet code/src_corelib_global_qglobal.cpp 54

    \sa qOverload, qNonConstOverload, {Differences between String-Based
    and Functor-Based Connections}
*/

/*!
    \macro QT_VERSION_CHECK
    \relates <QtGlobal>

    Turns the major, minor and patch numbers of a version into an
    integer, 0xMMNNPP (MM = major, NN = minor, PP = patch). This can
    be compared with another similarly processed version id.

    Example:

    \snippet code/src_corelib_global_qglobal.cpp qt-version-check

    \sa QT_VERSION
*/

/*!
    \macro QT_VERSION
    \relates <QtGlobal>

    This macro expands a numeric value of the form 0xMMNNPP (MM =
    major, NN = minor, PP = patch) that specifies Qt's version
    number. For example, if you compile your application against Qt
    4.1.2, the QT_VERSION macro will expand to 0x040102.

    You can use QT_VERSION to use the latest Qt features where
    available.

    Example:

    \snippet code/src_corelib_global_qglobal.cpp 16

    \sa QT_VERSION_STR, qVersion()
*/

/*!
    \macro QT_VERSION_STR
    \relates <QtGlobal>

    This macro expands to a string that specifies Qt's version number
    (for example, "4.1.2"). This is the version against which the
    application is compiled.

    \sa qVersion(), QT_VERSION
*/

/*!
    \relates <QtGlobal>

    Returns the version number of Qt at run-time as a string (for
    example, "4.1.2"). This may be a different version than the
    version the application was compiled against.

    \sa QT_VERSION_STR, QLibraryInfo::version()
*/

const char *qVersion() noexcept
{
    return QT_VERSION_STR;
}

bool qSharedBuild() noexcept
{
#ifdef QT_SHARED
    return true;
#else
    return false;
#endif
}

/*****************************************************************************
  System detection routines
 *****************************************************************************/

/*!
    \class QSysInfo
    \inmodule QtCore
    \brief The QSysInfo class provides information about the system.

    \list
    \li \l WordSize specifies the size of a pointer for the platform
       on which the application is compiled.
    \li \l ByteOrder specifies whether the platform is big-endian or
       little-endian.
    \endlist

    Some constants are defined only on certain platforms. You can use
    the preprocessor symbols Q_OS_WIN and Q_OS_MACOS to test that
    the application is compiled under Windows or \macos.

    \sa QLibraryInfo
*/

/*!
    \enum QSysInfo::Sizes

    This enum provides platform-specific information about the sizes of data
    structures used by the underlying architecture.

    \value WordSize The size in bits of a pointer for the platform on which
           the application is compiled (32 or 64).
*/

/*!
    \enum QSysInfo::Endian

    \value BigEndian  Big-endian byte order (also called Network byte order)
    \value LittleEndian  Little-endian byte order
    \value ByteOrder  Equals BigEndian or LittleEndian, depending on
                      the platform's byte order.
*/

/*!
    \macro Q_OS_DARWIN
    \relates <QtGlobal>

    Defined on Darwin-based operating systems such as \macos, iOS, watchOS, and tvOS.
*/

/*!
    \macro Q_OS_MAC
    \relates <QtGlobal>

    Deprecated synonym for \c Q_OS_DARWIN. Do not use.
 */

/*!
    \macro Q_OS_OSX
    \relates <QtGlobal>

    Deprecated synonym for \c Q_OS_MACOS. Do not use.
 */

/*!
    \macro Q_OS_MACOS
    \relates <QtGlobal>

    Defined on \macos.
 */

/*!
    \macro Q_OS_IOS
    \relates <QtGlobal>

    Defined on iOS.
 */

/*!
    \macro Q_OS_WATCHOS
    \relates <QtGlobal>

    Defined on watchOS.
 */

/*!
    \macro Q_OS_TVOS
    \relates <QtGlobal>

    Defined on tvOS.
 */

/*!
    \macro Q_OS_WIN
    \relates <QtGlobal>

    Defined on all supported versions of Windows. That is, if
    \l Q_OS_WIN32 or \l Q_OS_WIN64 is defined.
*/

/*!
    \macro Q_OS_WINDOWS
    \relates <QtGlobal>

    This is a synonym for Q_OS_WIN.
*/

/*!
    \macro Q_OS_WIN32
    \relates <QtGlobal>

    Defined on 32-bit and 64-bit versions of Windows.
*/

/*!
    \macro Q_OS_WIN64
    \relates <QtGlobal>

    Defined on 64-bit versions of Windows.
*/

/*!
    \macro Q_OS_CYGWIN
    \relates <QtGlobal>

    Defined on Cygwin.
*/

/*!
    \macro Q_OS_SOLARIS
    \relates <QtGlobal>

    Defined on Sun Solaris.
*/

/*!
    \macro Q_OS_HPUX
    \relates <QtGlobal>

    Defined on HP-UX.
*/

/*!
    \macro Q_OS_LINUX
    \relates <QtGlobal>

    Defined on Linux.
*/

/*!
    \macro Q_OS_ANDROID
    \relates <QtGlobal>

    Defined on Android.
*/

/*!
    \macro Q_OS_FREEBSD
    \relates <QtGlobal>

    Defined on FreeBSD.
*/

/*!
    \macro Q_OS_NETBSD
    \relates <QtGlobal>

    Defined on NetBSD.
*/

/*!
    \macro Q_OS_OPENBSD
    \relates <QtGlobal>

    Defined on OpenBSD.
*/

/*!
    \macro Q_OS_AIX
    \relates <QtGlobal>

    Defined on AIX.
*/

/*!
    \macro Q_OS_HURD
    \relates <QtGlobal>

    Defined on GNU Hurd.
*/

/*!
    \macro Q_OS_QNX
    \relates <QtGlobal>

    Defined on QNX Neutrino.
*/

/*!
    \macro Q_OS_LYNX
    \relates <QtGlobal>

    Defined on LynxOS.
*/

/*!
    \macro Q_OS_BSD4
    \relates <QtGlobal>

    Defined on Any BSD 4.4 system.
*/

/*!
    \macro Q_OS_UNIX
    \relates <QtGlobal>

    Defined on Any UNIX BSD/SYSV system.
*/

/*!
    \macro Q_OS_WASM
    \relates <QtGlobal>

    Defined on Web Assembly.
*/

/*!
    \macro Q_CC_SYM
    \relates <QtGlobal>

    Defined if the application is compiled using Digital Mars C/C++
    (used to be Symantec C++).
*/

/*!
    \macro Q_CC_MSVC
    \relates <QtGlobal>

    Defined if the application is compiled using Microsoft Visual
    C/C++, Intel C++ for Windows.
*/

/*!
    \macro Q_CC_CLANG
    \relates <QtGlobal>

    Defined if the application is compiled using Clang.
*/

/*!
    \macro Q_CC_BOR
    \relates <QtGlobal>

    Defined if the application is compiled using Borland/Turbo C++.
*/

/*!
    \macro Q_CC_WAT
    \relates <QtGlobal>

    Defined if the application is compiled using Watcom C++.
*/

/*!
    \macro Q_CC_GNU
    \relates <QtGlobal>

    Defined if the application is compiled using GNU C++.
*/

/*!
    \macro Q_CC_COMEAU
    \relates <QtGlobal>

    Defined if the application is compiled using Comeau C++.
*/

/*!
    \macro Q_CC_EDG
    \relates <QtGlobal>

    Defined if the application is compiled using Edison Design Group
    C++.
*/

/*!
    \macro Q_CC_OC
    \relates <QtGlobal>

    Defined if the application is compiled using CenterLine C++.
*/

/*!
    \macro Q_CC_SUN
    \relates <QtGlobal>

    Defined if the application is compiled using Forte Developer, or
    Sun Studio C++.
*/

/*!
    \macro Q_CC_MIPS
    \relates <QtGlobal>

    Defined if the application is compiled using MIPSpro C++.
*/

/*!
    \macro Q_CC_DEC
    \relates <QtGlobal>

    Defined if the application is compiled using DEC C++.
*/

/*!
    \macro Q_CC_HPACC
    \relates <QtGlobal>

    Defined if the application is compiled using HP aC++.
*/

/*!
    \macro Q_CC_USLC
    \relates <QtGlobal>

    Defined if the application is compiled using SCO OUDK and UDK.
*/

/*!
    \macro Q_CC_CDS
    \relates <QtGlobal>

    Defined if the application is compiled using Reliant C++.
*/

/*!
    \macro Q_CC_KAI
    \relates <QtGlobal>

    Defined if the application is compiled using KAI C++.
*/

/*!
    \macro Q_CC_INTEL
    \relates <QtGlobal>

    Defined if the application is compiled using Intel C++ for Linux,
    Intel C++ for Windows.
*/

/*!
    \macro Q_CC_HIGHC
    \relates <QtGlobal>

    Defined if the application is compiled using MetaWare High C/C++.
*/

/*!
    \macro Q_CC_PGI
    \relates <QtGlobal>

    Defined if the application is compiled using Portland Group C++.
*/

/*!
    \macro Q_CC_GHS
    \relates <QtGlobal>

    Defined if the application is compiled using Green Hills
    Optimizing C++ Compilers.
*/

/*!
    \macro Q_PROCESSOR_ALPHA
    \relates <QtGlobal>

    Defined if the application is compiled for Alpha processors.

    \sa QSysInfo::buildCpuArchitecture()
*/

/*!
    \macro Q_PROCESSOR_ARM
    \relates <QtGlobal>

    Defined if the application is compiled for ARM processors. Qt currently
    supports three optional ARM revisions: \l Q_PROCESSOR_ARM_V5, \l
    Q_PROCESSOR_ARM_V6, and \l Q_PROCESSOR_ARM_V7.

    \sa QSysInfo::buildCpuArchitecture()
*/
/*!
    \macro Q_PROCESSOR_ARM_V5
    \relates <QtGlobal>

    Defined if the application is compiled for ARMv5 processors. The \l
    Q_PROCESSOR_ARM macro is also defined when Q_PROCESSOR_ARM_V5 is defined.

    \sa QSysInfo::buildCpuArchitecture()
*/
/*!
    \macro Q_PROCESSOR_ARM_V6
    \relates <QtGlobal>

    Defined if the application is compiled for ARMv6 processors. The \l
    Q_PROCESSOR_ARM and \l Q_PROCESSOR_ARM_V5 macros are also defined when
    Q_PROCESSOR_ARM_V6 is defined.

    \sa QSysInfo::buildCpuArchitecture()
*/
/*!
    \macro Q_PROCESSOR_ARM_V7
    \relates <QtGlobal>

    Defined if the application is compiled for ARMv7 processors. The \l
    Q_PROCESSOR_ARM, \l Q_PROCESSOR_ARM_V5, and \l Q_PROCESSOR_ARM_V6 macros
    are also defined when Q_PROCESSOR_ARM_V7 is defined.

    \sa QSysInfo::buildCpuArchitecture()
*/

/*!
    \macro Q_PROCESSOR_AVR32
    \relates <QtGlobal>

    Defined if the application is compiled for AVR32 processors.

    \sa QSysInfo::buildCpuArchitecture()
*/

/*!
    \macro Q_PROCESSOR_BLACKFIN
    \relates <QtGlobal>

    Defined if the application is compiled for Blackfin processors.

    \sa QSysInfo::buildCpuArchitecture()
*/

/*!
    \macro Q_PROCESSOR_IA64
    \relates <QtGlobal>

    Defined if the application is compiled for IA-64 processors. This includes
    all Itanium and Itanium 2 processors.

    \sa QSysInfo::buildCpuArchitecture()
*/

/*!
    \macro Q_PROCESSOR_MIPS
    \relates <QtGlobal>

    Defined if the application is compiled for MIPS processors. Qt currently
    supports seven MIPS revisions: \l Q_PROCESSOR_MIPS_I, \l
    Q_PROCESSOR_MIPS_II, \l Q_PROCESSOR_MIPS_III, \l Q_PROCESSOR_MIPS_IV, \l
    Q_PROCESSOR_MIPS_V, \l Q_PROCESSOR_MIPS_32, and \l Q_PROCESSOR_MIPS_64.

    \sa QSysInfo::buildCpuArchitecture()
*/
/*!
    \macro Q_PROCESSOR_MIPS_I
    \relates <QtGlobal>

    Defined if the application is compiled for MIPS-I processors. The \l
    Q_PROCESSOR_MIPS macro is also defined when Q_PROCESSOR_MIPS_I is defined.

    \sa QSysInfo::buildCpuArchitecture()
*/
/*!
    \macro Q_PROCESSOR_MIPS_II
    \relates <QtGlobal>

    Defined if the application is compiled for MIPS-II processors. The \l
    Q_PROCESSOR_MIPS and \l Q_PROCESSOR_MIPS_I macros are also defined when
    Q_PROCESSOR_MIPS_II is defined.

    \sa QSysInfo::buildCpuArchitecture()
*/
/*!
    \macro Q_PROCESSOR_MIPS_32
    \relates <QtGlobal>

    Defined if the application is compiled for MIPS32 processors. The \l
    Q_PROCESSOR_MIPS, \l Q_PROCESSOR_MIPS_I, and \l Q_PROCESSOR_MIPS_II macros
    are also defined when Q_PROCESSOR_MIPS_32 is defined.

    \sa QSysInfo::buildCpuArchitecture()
*/
/*!
    \macro Q_PROCESSOR_MIPS_III
    \relates <QtGlobal>

    Defined if the application is compiled for MIPS-III processors. The \l
    Q_PROCESSOR_MIPS, \l Q_PROCESSOR_MIPS_I, and \l Q_PROCESSOR_MIPS_II macros
    are also defined when Q_PROCESSOR_MIPS_III is defined.

    \sa QSysInfo::buildCpuArchitecture()
*/
/*!
    \macro Q_PROCESSOR_MIPS_IV
    \relates <QtGlobal>

    Defined if the application is compiled for MIPS-IV processors. The \l
    Q_PROCESSOR_MIPS, \l Q_PROCESSOR_MIPS_I, \l Q_PROCESSOR_MIPS_II, and \l
    Q_PROCESSOR_MIPS_III macros are also defined when Q_PROCESSOR_MIPS_IV is
    defined.

    \sa QSysInfo::buildCpuArchitecture()
*/
/*!
    \macro Q_PROCESSOR_MIPS_V
    \relates <QtGlobal>

    Defined if the application is compiled for MIPS-V processors. The \l
    Q_PROCESSOR_MIPS, \l Q_PROCESSOR_MIPS_I, \l Q_PROCESSOR_MIPS_II, \l
    Q_PROCESSOR_MIPS_III, and \l Q_PROCESSOR_MIPS_IV macros are also defined
    when Q_PROCESSOR_MIPS_V is defined.

    \sa QSysInfo::buildCpuArchitecture()
*/
/*!
    \macro Q_PROCESSOR_MIPS_64
    \relates <QtGlobal>

    Defined if the application is compiled for MIPS64 processors. The \l
    Q_PROCESSOR_MIPS, \l Q_PROCESSOR_MIPS_I, \l Q_PROCESSOR_MIPS_II, \l
    Q_PROCESSOR_MIPS_III, \l Q_PROCESSOR_MIPS_IV, and \l Q_PROCESSOR_MIPS_V
    macros are also defined when Q_PROCESSOR_MIPS_64 is defined.

    \sa QSysInfo::buildCpuArchitecture()
*/

/*!
    \macro Q_PROCESSOR_POWER
    \relates <QtGlobal>

    Defined if the application is compiled for POWER processors. Qt currently
    supports two Power variants: \l Q_PROCESSOR_POWER_32 and \l
    Q_PROCESSOR_POWER_64.

    \sa QSysInfo::buildCpuArchitecture()
*/
/*!
    \macro Q_PROCESSOR_POWER_32
    \relates <QtGlobal>

    Defined if the application is compiled for 32-bit Power processors. The \l
    Q_PROCESSOR_POWER macro is also defined when Q_PROCESSOR_POWER_32 is
    defined.

    \sa QSysInfo::buildCpuArchitecture()
*/
/*!
    \macro Q_PROCESSOR_POWER_64
    \relates <QtGlobal>

    Defined if the application is compiled for 64-bit Power processors. The \l
    Q_PROCESSOR_POWER macro is also defined when Q_PROCESSOR_POWER_64 is
    defined.

    \sa QSysInfo::buildCpuArchitecture()
*/

/*!
    \macro Q_PROCESSOR_RISCV
    \relates <QtGlobal>
    \since 5.13

    Defined if the application is compiled for RISC-V processors. Qt currently
    supports two RISC-V variants: \l Q_PROCESSOR_RISCV_32 and \l
    Q_PROCESSOR_RISCV_64.

    \sa QSysInfo::buildCpuArchitecture()
*/

/*!
    \macro Q_PROCESSOR_RISCV_32
    \relates <QtGlobal>
    \since 5.13

    Defined if the application is compiled for 32-bit RISC-V processors. The \l
    Q_PROCESSOR_RISCV macro is also defined when Q_PROCESSOR_RISCV_32 is
    defined.

    \sa QSysInfo::buildCpuArchitecture()
*/

/*!
    \macro Q_PROCESSOR_RISCV_64
    \relates <QtGlobal>
    \since 5.13

    Defined if the application is compiled for 64-bit RISC-V processors. The \l
    Q_PROCESSOR_RISCV macro is also defined when Q_PROCESSOR_RISCV_64 is
    defined.

    \sa QSysInfo::buildCpuArchitecture()
*/

/*!
    \macro Q_PROCESSOR_S390
    \relates <QtGlobal>

    Defined if the application is compiled for S/390 processors. Qt supports
    one optional variant of S/390: Q_PROCESSOR_S390_X.

    \sa QSysInfo::buildCpuArchitecture()
*/
/*!
    \macro Q_PROCESSOR_S390_X
    \relates <QtGlobal>

    Defined if the application is compiled for S/390x processors. The \l
    Q_PROCESSOR_S390 macro is also defined when Q_PROCESSOR_S390_X is defined.

    \sa QSysInfo::buildCpuArchitecture()
*/

/*!
    \macro Q_PROCESSOR_SH
    \relates <QtGlobal>

    Defined if the application is compiled for SuperH processors. Qt currently
    supports one SuperH revision: \l Q_PROCESSOR_SH_4A.

    \sa QSysInfo::buildCpuArchitecture()
*/
/*!
    \macro Q_PROCESSOR_SH_4A
    \relates <QtGlobal>

    Defined if the application is compiled for SuperH 4A processors. The \l
    Q_PROCESSOR_SH macro is also defined when Q_PROCESSOR_SH_4A is defined.

    \sa QSysInfo::buildCpuArchitecture()
*/

/*!
    \macro Q_PROCESSOR_SPARC
    \relates <QtGlobal>

    Defined if the application is compiled for SPARC processors. Qt currently
    supports one optional SPARC revision: \l Q_PROCESSOR_SPARC_V9.

    \sa QSysInfo::buildCpuArchitecture()
*/
/*!
    \macro Q_PROCESSOR_SPARC_V9
    \relates <QtGlobal>

    Defined if the application is compiled for SPARC V9 processors. The \l
    Q_PROCESSOR_SPARC macro is also defined when Q_PROCESSOR_SPARC_V9 is
    defined.

    \sa QSysInfo::buildCpuArchitecture()
*/

/*!
    \macro Q_PROCESSOR_X86
    \relates <QtGlobal>

    Defined if the application is compiled for x86 processors. Qt currently
    supports two x86 variants: \l Q_PROCESSOR_X86_32 and \l Q_PROCESSOR_X86_64.

    \sa QSysInfo::buildCpuArchitecture()
*/
/*!
    \macro Q_PROCESSOR_X86_32
    \relates <QtGlobal>

    Defined if the application is compiled for 32-bit x86 processors. This
    includes all i386, i486, i586, and i686 processors. The \l Q_PROCESSOR_X86
    macro is also defined when Q_PROCESSOR_X86_32 is defined.

    \sa QSysInfo::buildCpuArchitecture()
*/
/*!
    \macro Q_PROCESSOR_X86_64
    \relates <QtGlobal>

    Defined if the application is compiled for 64-bit x86 processors. This
    includes all AMD64, Intel 64, and other x86_64/x64 processors. The \l
    Q_PROCESSOR_X86 macro is also defined when Q_PROCESSOR_X86_64 is defined.

    \sa QSysInfo::buildCpuArchitecture()
*/

/*!
  \macro QT_DISABLE_DEPRECATED_BEFORE
  \relates <QtGlobal>

  This macro can be defined in the project file to disable functions deprecated in
  a specified version of Qt or any earlier version. The default version number is 5.0,
  meaning that functions deprecated in or before Qt 5.0 will not be included.

  For instance, when using a future release of Qt 5, set
  \c{QT_DISABLE_DEPRECATED_BEFORE=0x050100} to disable functions deprecated in
  Qt 5.1 and earlier. In any release, set
  \c{QT_DISABLE_DEPRECATED_BEFORE=0x000000} to enable all functions, including
  the ones deprecated in Qt 5.0.

  \sa QT_DEPRECATED_WARNINGS
 */


/*!
  \macro QT_DEPRECATED_WARNINGS
  \relates <QtGlobal>

  Since Qt 5.13, this macro has no effect. In Qt 5.12 and before, if this macro
  is defined, the compiler will generate warnings if any API declared as
  deprecated by Qt is used.

  \sa QT_DISABLE_DEPRECATED_BEFORE, QT_NO_DEPRECATED_WARNINGS
 */

/*!
  \macro QT_NO_DEPRECATED_WARNINGS
  \relates <QtGlobal>
  \since 5.13

  This macro can be used to suppress deprecation warnings that would otherwise
  be generated when using deprecated APIs.

  \sa QT_DISABLE_DEPRECATED_BEFORE
*/

#if defined(QT_BUILD_QMAKE)
// needed to bootstrap qmake
static const unsigned int qt_one = 1;
const int QSysInfo::ByteOrder = ((*((unsigned char *) &qt_one) == 0) ? BigEndian : LittleEndian);
#endif

#if defined(Q_OS_MAC)

QT_BEGIN_INCLUDE_NAMESPACE
#include "private/qcore_mac_p.h"
#include "qnamespace.h"
QT_END_INCLUDE_NAMESPACE

#ifdef Q_OS_DARWIN
static const char *osVer_helper(QOperatingSystemVersion version = QOperatingSystemVersion::current())
{
#ifdef Q_OS_MACOS
    if (version.majorVersion() == 10) {
        switch (version.minorVersion()) {
        case 9:
            return "Mavericks";
        case 10:
            return "Yosemite";
        case 11:
            return "El Capitan";
        case 12:
            return "Sierra";
        case 13:
            return "High Sierra";
        case 14:
            return "Mojave";
        }
    }
    // unknown, future version
#else
    Q_UNUSED(version);
#endif
    return 0;
}
#endif

#elif defined(Q_OS_WIN) || defined(Q_OS_CYGWIN)

QT_BEGIN_INCLUDE_NAMESPACE
#include "qt_windows.h"
QT_END_INCLUDE_NAMESPACE

#  ifndef QT_BOOTSTRAPPED
class QWindowsSockInit
{
public:
    QWindowsSockInit();
    ~QWindowsSockInit();
    int version;
};

QWindowsSockInit::QWindowsSockInit()
:   version(0)
{
    //### should we try for 2.2 on all platforms ??
    WSAData wsadata;

    // IPv6 requires Winsock v2.0 or better.
    if (WSAStartup(MAKEWORD(2, 0), &wsadata) != 0) {
        qWarning("QTcpSocketAPI: WinSock v2.0 initialization failed.");
    } else {
        version = 0x20;
    }
}

QWindowsSockInit::~QWindowsSockInit()
{
    WSACleanup();
}
Q_GLOBAL_STATIC(QWindowsSockInit, winsockInit)
#  endif // QT_BOOTSTRAPPED

static QString readVersionRegistryString(const wchar_t *subKey)
{
#if !defined(QT_BUILD_QMAKE)
     return QWinRegistryKey(HKEY_LOCAL_MACHINE, LR"(SOFTWARE\Microsoft\Windows NT\CurrentVersion)")
            .stringValue(subKey);
#else
     Q_UNUSED(subKey);
     return QString();
#endif
}

static inline QString windows10ReleaseId()
{
    return readVersionRegistryString(L"ReleaseId");
}

static inline QString windows7Build()
{
    return readVersionRegistryString(L"CurrentBuild");
}

static QString winSp_helper()
{
    const auto osv = qWindowsVersionInfo();
    const qint16 major = osv.wServicePackMajor;
    if (major) {
        QString sp = QStringLiteral("SP ") + QString::number(major);
        const qint16 minor = osv.wServicePackMinor;
        if (minor)
            sp += QLatin1Char('.') + QString::number(minor);

        return sp;
    }
    return QString();
}

static const char *osVer_helper(QOperatingSystemVersion version = QOperatingSystemVersion::current())
{
    Q_UNUSED(version);
    const OSVERSIONINFOEX osver = qWindowsVersionInfo();
    const bool workstation = osver.wProductType == VER_NT_WORKSTATION;

#define Q_WINVER(major, minor) (major << 8 | minor)
    switch (Q_WINVER(osver.dwMajorVersion, osver.dwMinorVersion)) {
    case Q_WINVER(6, 1):
        return workstation ? "7" : "Server 2008 R2";
    case Q_WINVER(6, 2):
        return workstation ? "8" : "Server 2012";
    case Q_WINVER(6, 3):
        return workstation ? "8.1" : "Server 2012 R2";
    case Q_WINVER(10, 0):
        return workstation ? "10" : "Server 2016";
    }
#undef Q_WINVER
    // unknown, future version
    return 0;
}

#endif
#if defined(Q_OS_UNIX)
#  if (defined(Q_OS_LINUX) && !defined(Q_OS_ANDROID)) || defined(Q_OS_FREEBSD)
#    define USE_ETC_OS_RELEASE
struct QUnixOSVersion
{
                                    // from /etc/os-release         older /etc/lsb-release         // redhat /etc/redhat-release         // debian /etc/debian_version
    QString productType;            // $ID                          $DISTRIB_ID                    // single line file containing:       // Debian
    QString productVersion;         // $VERSION_ID                  $DISTRIB_RELEASE               // <Vendor_ID release Version_ID>     // single line file <Release_ID/sid>
    QString prettyName;             // $PRETTY_NAME                 $DISTRIB_DESCRIPTION
};

static QString unquote(const char *begin, const char *end)
{
    // man os-release says:
    // Variable assignment values must be enclosed in double
    // or single quotes if they include spaces, semicolons or
    // other special characters outside of A–Z, a–z, 0–9. Shell
    // special characters ("$", quotes, backslash, backtick)
    // must be escaped with backslashes, following shell style.
    // All strings should be in UTF-8 format, and non-printable
    // characters should not be used. It is not supported to
    // concatenate multiple individually quoted strings.
    if (*begin == '"') {
        Q_ASSERT(end[-1] == '"');
        return QString::fromUtf8(begin + 1, end - begin - 2);
    }
    return QString::fromUtf8(begin, end - begin);
}
static QByteArray getEtcFileContent(const char *filename)
{
    // we're avoiding QFile here
    int fd = qt_safe_open(filename, O_RDONLY);
    if (fd == -1)
        return QByteArray();

    QT_STATBUF sbuf;
    if (QT_FSTAT(fd, &sbuf) == -1) {
        qt_safe_close(fd);
        return QByteArray();
    }

    QByteArray buffer(sbuf.st_size, Qt::Uninitialized);
    buffer.resize(qt_safe_read(fd, buffer.data(), sbuf.st_size));
    qt_safe_close(fd);
    return buffer;
}

static bool readEtcFile(QUnixOSVersion &v, const char *filename,
                        const QByteArray &idKey, const QByteArray &versionKey, const QByteArray &prettyNameKey)
{

    QByteArray buffer = getEtcFileContent(filename);
    if (buffer.isEmpty())
        return false;

    const char *ptr = buffer.constData();
    const char *end = buffer.constEnd();
    const char *eol;
    QByteArray line;
    for (; ptr != end; ptr = eol + 1) {
        // find the end of the line after ptr
        eol = static_cast<const char *>(memchr(ptr, '\n', end - ptr));
        if (!eol)
            eol = end - 1;
        line.setRawData(ptr, eol - ptr);

        if (line.startsWith(idKey)) {
            ptr += idKey.length();
            v.productType = unquote(ptr, eol);
            continue;
        }

        if (line.startsWith(prettyNameKey)) {
            ptr += prettyNameKey.length();
            v.prettyName = unquote(ptr, eol);
            continue;
        }

        if (line.startsWith(versionKey)) {
            ptr += versionKey.length();
            v.productVersion = unquote(ptr, eol);
            continue;
        }
    }

    return true;
}

static bool readOsRelease(QUnixOSVersion &v)
{
    QByteArray id = QByteArrayLiteral("ID=");
    QByteArray versionId = QByteArrayLiteral("VERSION_ID=");
    QByteArray prettyName = QByteArrayLiteral("PRETTY_NAME=");

    // man os-release(5) says:
    // The file /etc/os-release takes precedence over /usr/lib/os-release.
    // Applications should check for the former, and exclusively use its data
    // if it exists, and only fall back to /usr/lib/os-release if it is
    // missing.
    return readEtcFile(v, "/etc/os-release", id, versionId, prettyName) ||
            readEtcFile(v, "/usr/lib/os-release", id, versionId, prettyName);
}

static bool readEtcLsbRelease(QUnixOSVersion &v)
{
    bool ok = readEtcFile(v, "/etc/lsb-release", QByteArrayLiteral("DISTRIB_ID="),
                          QByteArrayLiteral("DISTRIB_RELEASE="), QByteArrayLiteral("DISTRIB_DESCRIPTION="));
    if (ok && (v.prettyName.isEmpty() || v.prettyName == v.productType)) {
        // some distributions have redundant information for the pretty name,
        // so try /etc/<lowercasename>-release

        // we're still avoiding QFile here
        QByteArray distrorelease = "/etc/" + v.productType.toLatin1().toLower() + "-release";
        int fd = qt_safe_open(distrorelease, O_RDONLY);
        if (fd != -1) {
            QT_STATBUF sbuf;
            if (QT_FSTAT(fd, &sbuf) != -1 && sbuf.st_size > v.prettyName.length()) {
                // file apparently contains interesting information
                QByteArray buffer(sbuf.st_size, Qt::Uninitialized);
                buffer.resize(qt_safe_read(fd, buffer.data(), sbuf.st_size));
                v.prettyName = QString::fromLatin1(buffer.trimmed());
            }
            qt_safe_close(fd);
        }
    }

    // some distributions have a /etc/lsb-release file that does not provide the values
    // we are looking for, i.e. DISTRIB_ID, DISTRIB_RELEASE and DISTRIB_DESCRIPTION.
    // Assuming that neither DISTRIB_ID nor DISTRIB_RELEASE were found, or contained valid values,
    // returning false for readEtcLsbRelease will allow further /etc/<lowercasename>-release parsing.
    return ok && !(v.productType.isEmpty() && v.productVersion.isEmpty());
}

#if defined(Q_OS_LINUX)
static QByteArray getEtcFileFirstLine(const char *fileName)
{
    QByteArray buffer = getEtcFileContent(fileName);
    if (buffer.isEmpty())
        return QByteArray();

    const char *ptr = buffer.constData();
    int eol = buffer.indexOf("\n");
    return QByteArray(ptr, eol).trimmed();
}

static bool readEtcRedHatRelease(QUnixOSVersion &v)
{
    // /etc/redhat-release analysed should be a one line file
    // the format of its content is <Vendor_ID release Version>
    // i.e. "Red Hat Enterprise Linux Workstation release 6.5 (Santiago)"
    QByteArray line = getEtcFileFirstLine("/etc/redhat-release");
    if (line.isEmpty())
        return false;

    v.prettyName = QString::fromLatin1(line);

    const char keyword[] = "release ";
    int releaseIndex = line.indexOf(keyword);
    v.productType = QString::fromLatin1(line.mid(0, releaseIndex)).remove(QLatin1Char(' '));
    int spaceIndex = line.indexOf(' ', releaseIndex + strlen(keyword));
    v.productVersion = QString::fromLatin1(line.mid(releaseIndex + strlen(keyword),
                                                    spaceIndex > -1 ? spaceIndex - releaseIndex - int(strlen(keyword)) : -1));
    return true;
}

static bool readEtcDebianVersion(QUnixOSVersion &v)
{
    // /etc/debian_version analysed should be a one line file
    // the format of its content is <Release_ID/sid>
    // i.e. "jessie/sid"
    QByteArray line = getEtcFileFirstLine("/etc/debian_version");
    if (line.isEmpty())
        return false;

    v.productType = QStringLiteral("Debian");
    v.productVersion = QString::fromLatin1(line);
    return true;
}
#endif

static bool findUnixOsVersion(QUnixOSVersion &v)
{
    if (readOsRelease(v))
        return true;
    if (readEtcLsbRelease(v))
        return true;
#if defined(Q_OS_LINUX)
    if (readEtcRedHatRelease(v))
        return true;
    if (readEtcDebianVersion(v))
        return true;
#endif
    return false;
}
#  endif // USE_ETC_OS_RELEASE
#endif // Q_OS_UNIX

#if defined(Q_OS_ANDROID) && !defined(Q_OS_ANDROID_EMBEDDED)
static const char *osVer_helper(QOperatingSystemVersion)
{
/* Data:



Cupcake
Donut
Eclair
Eclair
Eclair
Froyo
Gingerbread
Gingerbread
Honeycomb
Honeycomb
Honeycomb
Ice Cream Sandwich
Ice Cream Sandwich
Jelly Bean
Jelly Bean
Jelly Bean
KitKat
KitKat
Lollipop
Lollipop
Marshmallow
Nougat
Nougat
Oreo
 */
    static const char versions_string[] =
        "\0"
        "Cupcake\0"
        "Donut\0"
        "Eclair\0"
        "Froyo\0"
        "Gingerbread\0"
        "Honeycomb\0"
        "Ice Cream Sandwich\0"
        "Jelly Bean\0"
        "KitKat\0"
        "Lollipop\0"
        "Marshmallow\0"
        "Nougat\0"
        "Oreo\0"
        "\0";

    static const int versions_indices[] = {
           0,    0,    0,    1,    9,   15,   15,   15,
          22,   28,   28,   40,   40,   40,   50,   50,
          69,   69,   69,   80,   80,   87,   87,   96,
         108,  108,  115,   -1
    };

    static const int versions_count = (sizeof versions_indices) / (sizeof versions_indices[0]);

    // https://source.android.com/source/build-numbers.html
    // https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels
    const int sdk_int = QJNIObjectPrivate::getStaticField<jint>("android/os/Build$VERSION", "SDK_INT");
    return &versions_string[versions_indices[qBound(0, sdk_int, versions_count - 1)]];
}
#endif

/*!
    \since 5.4

    Returns the architecture of the CPU that Qt was compiled for, in text
    format. Note that this may not match the actual CPU that the application is
    running on if there's an emulation layer or if the CPU supports multiple
    architectures (like x86-64 processors supporting i386 applications). To
    detect that, use currentCpuArchitecture().

    Values returned by this function are stable and will not change over time,
    so applications can rely on the returned value as an identifier, except
    that new CPU types may be added over time.

    Typical returned values are (note: list not exhaustive):
    \list
        \li "arm"
        \li "arm64"
        \li "i386"
        \li "ia64"
        \li "mips"
        \li "mips64"
        \li "power"
        \li "power64"
        \li "sparc"
        \li "sparcv9"
        \li "x86_64"
    \endlist

    \sa QSysInfo::buildAbi(), QSysInfo::currentCpuArchitecture()
*/
QString QSysInfo::buildCpuArchitecture()
{
    return QStringLiteral(ARCH_PROCESSOR);
}

/*!
    \since 5.4

    Returns the architecture of the CPU that the application is running on, in
    text format. Note that this function depends on what the OS will report and
    may not detect the actual CPU architecture if the OS hides that information
    or is unable to provide it. For example, a 32-bit OS running on a 64-bit
    CPU is usually unable to determine the CPU is actually capable of running
    64-bit programs.

    Values returned by this function are mostly stable: an attempt will be made
    to ensure that they stay constant over time and match the values returned
    by QSysInfo::builldCpuArchitecture(). However, due to the nature of the
    operating system functions being used, there may be discrepancies.

    Typical returned values are (note: list not exhaustive):
    \list
        \li "arm"
        \li "arm64"
        \li "i386"
        \li "ia64"
        \li "mips"
        \li "mips64"
        \li "power"
        \li "power64"
        \li "sparc"
        \li "sparcv9"
        \li "x86_64"
    \endlist

    \sa QSysInfo::buildAbi(), QSysInfo::buildCpuArchitecture()
 */
QString QSysInfo::currentCpuArchitecture()
{
#if defined(Q_OS_WIN)
    // We don't need to catch all the CPU architectures in this function;
    // only those where the host CPU might be different than the build target
    // (usually, 64-bit platforms).
    SYSTEM_INFO info;
    GetNativeSystemInfo(&info);
    switch (info.wProcessorArchitecture) {
#  ifdef PROCESSOR_ARCHITECTURE_AMD64
    case PROCESSOR_ARCHITECTURE_AMD64:
        return QStringLiteral("x86_64");
#  endif
#  ifdef PROCESSOR_ARCHITECTURE_IA32_ON_WIN64
    case PROCESSOR_ARCHITECTURE_IA32_ON_WIN64:
#  endif
    case PROCESSOR_ARCHITECTURE_IA64:
        return QStringLiteral("ia64");
    }
#elif defined(Q_OS_DARWIN) && !defined(Q_OS_MACOS)
    // iOS-based OSes do not return the architecture on uname(2)'s result.
    return buildCpuArchitecture();
#elif defined(Q_OS_UNIX)
    long ret = -1;
    struct utsname u;

#  if defined(Q_OS_SOLARIS)
    // We need a special call for Solaris because uname(2) on x86 returns "i86pc" for
    // both 32- and 64-bit CPUs. Reference:
    // http://docs.oracle.com/cd/E18752_01/html/816-5167/sysinfo-2.html#REFMAN2sysinfo-2
    // http://fxr.watson.org/fxr/source/common/syscall/systeminfo.c?v=OPENSOLARIS
    // http://fxr.watson.org/fxr/source/common/conf/param.c?v=OPENSOLARIS;im=10#L530
    if (ret == -1)
        ret = sysinfo(SI_ARCHITECTURE_64, u.machine, sizeof u.machine);
#  endif

    if (ret == -1)
        ret = uname(&u);

    // we could use detectUnixVersion() above, but we only need a field no other function does
    if (ret != -1) {
        // the use of QT_BUILD_INTERNAL here is simply to ensure all branches build
        // as we don't often build on some of the less common platforms
#  if defined(Q_PROCESSOR_ARM) || defined(QT_BUILD_INTERNAL)
        if (strcmp(u.machine, "aarch64") == 0)
            return QStringLiteral("arm64");
        if (strncmp(u.machine, "armv", 4) == 0)
            return QStringLiteral("arm");
#  endif
#  if defined(Q_PROCESSOR_POWER) || defined(QT_BUILD_INTERNAL)
        // harmonize "powerpc" and "ppc" to "power"
        if (strncmp(u.machine, "ppc", 3) == 0)
            return QLatin1String("power") + QLatin1String(u.machine + 3);
        if (strncmp(u.machine, "powerpc", 7) == 0)
            return QLatin1String("power") + QLatin1String(u.machine + 7);
        if (strcmp(u.machine, "Power Macintosh") == 0)
            return QLatin1String("power");
#  endif
#  if defined(Q_PROCESSOR_SPARC) || defined(QT_BUILD_INTERNAL)
        // Solaris sysinfo(2) (above) uses "sparcv9", but uname -m says "sun4u";
        // Linux says "sparc64"
        if (strcmp(u.machine, "sun4u") == 0 || strcmp(u.machine, "sparc64") == 0)
            return QStringLiteral("sparcv9");
        if (strcmp(u.machine, "sparc32") == 0)
            return QStringLiteral("sparc");
#  endif
#  if defined(Q_PROCESSOR_X86) || defined(QT_BUILD_INTERNAL)
        // harmonize all "i?86" to "i386"
        if (strlen(u.machine) == 4 && u.machine[0] == 'i'
                && u.machine[2] == '8' && u.machine[3] == '6')
            return QStringLiteral("i386");
        if (strcmp(u.machine, "amd64") == 0) // Solaris
            return QStringLiteral("x86_64");
#  endif
        return QString::fromLatin1(u.machine);
    }
#endif
    return buildCpuArchitecture();
}

/*!
    \since 5.4

    Returns the full architecture string that Qt was compiled for. This string
    is useful for identifying different, incompatible builds. For example, it
    can be used as an identifier to request an upgrade package from a server.

    The values returned from this function are kept stable as follows: the
    mandatory components of the result will not change in future versions of
    Qt, but optional suffixes may be added.

    The returned value is composed of three or more parts, separated by dashes
    ("-"). They are:

    \table
    \header \li Component           \li Value
    \row    \li CPU Architecture    \li The same as QSysInfo::buildCpuArchitecture(), such as "arm", "i386", "mips" or "x86_64"
    \row    \li Endianness          \li "little_endian" or "big_endian"
    \row    \li Word size           \li Whether it's a 32- or 64-bit application. Possible values are:
                                        "llp64" (Windows 64-bit), "lp64" (Unix 64-bit), "ilp32" (32-bit)
    \row    \li (Optional) ABI      \li Zero or more components identifying different ABIs possible in this architecture.
                                        Currently, Qt has optional ABI components for ARM and MIPS processors: one
                                        component is the main ABI (such as "eabi", "o32", "n32", "o64"); another is
                                        whether the calling convention is using hardware floating point registers ("hardfloat"
                                        is present).

                                        Additionally, if Qt was configured with \c{-qreal float}, the ABI option tag "qreal_float"
                                        will be present. If Qt was configured with another type as qreal, that type is present after
                                        "qreal_", with all characters other than letters and digits escaped by an underscore, followed
                                        by two hex digits. For example, \c{-qreal long double} becomes "qreal_long_20double".
    \endtable

    \sa QSysInfo::buildCpuArchitecture()
*/
QString QSysInfo::buildAbi()
{
    // ARCH_FULL is a concatenation of strings (incl. ARCH_PROCESSOR), which breaks
    // QStringLiteral on MSVC. Since the concatenation behavior we want is specified
    // the same C++11 paper as the Unicode strings, we'll use that macro and hope
    // that Microsoft implements the new behavior when they add support for Unicode strings.
    return QStringLiteral(ARCH_FULL);
}

static QString unknownText()
{
    return QStringLiteral("unknown");
}

/*!
    \since 5.4

    Returns the type of the operating system kernel Qt was compiled for. It's
    also the kernel the application is running on, unless the host operating
    system is running a form of compatibility or virtualization layer.

    Values returned by this function are stable and will not change over time,
    so applications can rely on the returned value as an identifier, except
    that new OS kernel types may be added over time.

    On Windows, this function returns the type of Windows kernel, like "winnt".
    On Unix systems, it returns the same as the output of \c{uname
    -s} (lowercased).

    \note This function may return surprising values: it returns "linux"
    for all operating systems running Linux (including Android), "qnx" for all
    operating systems running QNX, "freebsd" for
    Debian/kFreeBSD, and "darwin" for \macos and iOS. For information on the type
    of product the application is running on, see productType().

    \sa QFileSelector, kernelVersion(), productType(), productVersion(), prettyProductName()
*/
QString QSysInfo::kernelType()
{
#if defined(Q_OS_WIN)
    return QStringLiteral("winnt");
#elif defined(Q_OS_UNIX)
    struct utsname u;
    if (uname(&u) == 0)
        return QString::fromLatin1(u.sysname).toLower();
#endif
    return unknownText();
}

/*!
    \since 5.4

    Returns the release version of the operating system kernel. On Windows, it
    returns the version of the NT kernel. On Unix systems, including
    Android and \macos, it returns the same as the \c{uname -r}
    command would return.

    If the version could not be determined, this function may return an empty
    string.

    \sa kernelType(), productType(), productVersion(), prettyProductName()
*/
QString QSysInfo::kernelVersion()
{
#ifdef Q_OS_WIN
    const auto osver = QOperatingSystemVersion::current();
    return QString::number(osver.majorVersion()) + QLatin1Char('.') + QString::number(osver.minorVersion())
            + QLatin1Char('.') + QString::number(osver.microVersion());
#else
    struct utsname u;
    if (uname(&u) == 0)
        return QString::fromLatin1(u.release);
    return QString();
#endif
}


/*!
    \since 5.4

    Returns the product name of the operating system this application is
    running in. If the application is running on some sort of emulation or
    virtualization layer (such as WINE on a Unix system), this function will
    inspect the emulation / virtualization layer.

    Values returned by this function are stable and will not change over time,
    so applications can rely on the returned value as an identifier, except
    that new OS types may be added over time.

    \b{Linux and Android note}: this function returns "android" for Linux
    systems running Android userspace, notably when using the Bionic library.
    For all other Linux systems, regardless of C library being used, it tries
    to determine the distribution name and returns that. If determining the
    distribution name failed, it returns "unknown".

    \b{\macos note}: this function returns "osx" for all \macos systems,
    regardless of Apple naming convention. The returned string will be updated
    for Qt 6. Note that this function erroneously returned "macos" for \macos
    10.12 in Qt versions 5.6.2, 5.7.1, and 5.8.0.

    \b{Darwin, iOS, tvOS, and watchOS note}: this function returns "ios" for
    iOS systems, "tvos" for tvOS systems, "watchos" for watchOS systems, and
    "darwin" in case the system could not be determined.

    \b{FreeBSD note}: this function returns "debian" for Debian/kFreeBSD and
    "unknown" otherwise.

    \b{Windows note}: this function return "windows"

    For other Unix-type systems, this function usually returns "unknown".

    \sa QFileSelector, kernelType(), kernelVersion(), productVersion(), prettyProductName()
*/
QString QSysInfo::productType()
{
    // similar, but not identical to QFileSelectorPrivate::platformSelectors
#if defined(Q_OS_WIN)
    return QStringLiteral("windows");

#elif defined(Q_OS_QNX)
    return QStringLiteral("qnx");

#elif defined(Q_OS_ANDROID)
    return QStringLiteral("android");

#elif defined(Q_OS_IOS)
    return QStringLiteral("ios");
#elif defined(Q_OS_TVOS)
    return QStringLiteral("tvos");
#elif defined(Q_OS_WATCHOS)
    return QStringLiteral("watchos");
#elif defined(Q_OS_MACOS)
    return QStringLiteral("macos");
#elif defined(Q_OS_DARWIN)
    return QStringLiteral("darwin");

#elif defined(USE_ETC_OS_RELEASE) // Q_OS_UNIX
    QUnixOSVersion unixOsVersion;
    findUnixOsVersion(unixOsVersion);
    if (!unixOsVersion.productType.isEmpty())
        return unixOsVersion.productType;
#endif
    return unknownText();
}

/*!
    \since 5.4

    Returns the product version of the operating system in string form. If the
    version could not be determined, this function returns "unknown".

    It will return the Android, iOS, \macos, Windows full-product
    versions on those systems.

    Typical returned values are (note: list not exhaustive):
    \list
        \li "2016.09" (Amazon Linux AMI 2016.09)
        \li "7.1" (Android Nougat)
        \li "25" (Fedora 25)
        \li "10.1" (iOS 10.1)
        \li "10.12" (macOS Sierra)
        \li "10.0" (tvOS 10)
        \li "16.10" (Ubuntu 16.10)
        \li "3.1" (watchOS 3.1)
        \li "7 SP 1" (Windows 7 Service Pack 1)
        \li "8.1" (Windows 8.1)
        \li "10" (Windows 10)
        \li "Server 2016" (Windows Server 2016)
    \endlist

    On Linux systems, it will try to determine the distribution version and will
    return that. This is also done on Debian/kFreeBSD, so this function will
    return Debian version in that case.

    In all other Unix-type systems, this function always returns "unknown".

    \note The version string returned from this function is not guaranteed to
    be orderable. On Linux, the version of
    the distribution may jump unexpectedly, please refer to the distribution's
    documentation for versioning practices.

    \sa kernelType(), kernelVersion(), productType(), prettyProductName()
*/
QString QSysInfo::productVersion()
{
#if defined(Q_OS_ANDROID) || defined(Q_OS_DARWIN)
    const auto version = QOperatingSystemVersion::current();
    return QString::number(version.majorVersion()) + QLatin1Char('.') + QString::number(version.minorVersion());
#elif defined(Q_OS_WIN)
    const char *version = osVer_helper();
    if (version) {
        const QLatin1Char spaceChar(' ');
        return QString::fromLatin1(version).remove(spaceChar).toLower() + winSp_helper().remove(spaceChar).toLower();
    }
    // fall through

#elif defined(USE_ETC_OS_RELEASE) // Q_OS_UNIX
    QUnixOSVersion unixOsVersion;
    findUnixOsVersion(unixOsVersion);
    if (!unixOsVersion.productVersion.isEmpty())
        return unixOsVersion.productVersion;
#endif

    // fallback
    return unknownText();
}

/*!
    \since 5.4

    Returns a prettier form of productType() and productVersion(), containing
    other tokens like the operating system type, codenames and other
    information. The result of this function is suitable for displaying to the
    user, but not for long-term storage, as the string may change with updates
    to Qt.

    If productType() is "unknown", this function will instead use the
    kernelType() and kernelVersion() functions.

    \sa kernelType(), kernelVersion(), productType(), productVersion()
*/
QString QSysInfo::prettyProductName()
{
#if (defined(Q_OS_ANDROID) && !defined(Q_OS_ANDROID_EMBEDDED)) || defined(Q_OS_DARWIN) || defined(Q_OS_WIN)
    const auto version = QOperatingSystemVersion::current();
    const int majorVersion = version.majorVersion();
    const QString versionString = QString::number(majorVersion) + QLatin1Char('.')
        + QString::number(version.minorVersion());
    QString result = version.name() + QLatin1Char(' ');
    const char *name = osVer_helper(version);
    if (!name)
        return result + versionString;
    result += QLatin1String(name);
#  if !defined(Q_OS_WIN)
    return result + QLatin1String(" (") + versionString + QLatin1Char(')');
#  else
    // (resembling winver.exe): Windows 10 "Windows 10 Version 1809"
    if (majorVersion >= 10) {
        const auto releaseId = windows10ReleaseId();
        if (!releaseId.isEmpty())
            result += QLatin1String(" Version ") + releaseId;
        return result;
    }
    // Windows 7: "Windows 7 Version 6.1 (Build 7601: Service Pack 1)"
    result += QLatin1String(" Version ") + versionString + QLatin1String(" (");
    const auto build = windows7Build();
    if (!build.isEmpty())
        result += QLatin1String("Build ") + build;
    const auto servicePack = winSp_helper();
    if (!servicePack.isEmpty())
        result += QLatin1String(": ") + servicePack;
    return result + QLatin1Char(')');
#  endif // Windows
#elif defined(Q_OS_HAIKU)
    return QLatin1String("Haiku ") + productVersion();
#elif defined(Q_OS_UNIX)
#  ifdef USE_ETC_OS_RELEASE
    QUnixOSVersion unixOsVersion;
    findUnixOsVersion(unixOsVersion);
    if (!unixOsVersion.prettyName.isEmpty())
        return unixOsVersion.prettyName;
#  endif
    struct utsname u;
    if (uname(&u) == 0)
        return QString::fromLatin1(u.sysname) + QLatin1Char(' ') + QString::fromLatin1(u.release);
#endif
    return unknownText();
}

#ifndef QT_BOOTSTRAPPED
/*!
    \since 5.6

    Returns this machine's host name, if one is configured. Note that hostnames
    are not guaranteed to be globally unique, especially if they were
    configured automatically.

    This function does not guarantee the returned host name is a Fully
    Qualified Domain Name (FQDN). For that, use QHostInfo to resolve the
    returned name to an FQDN.

    This function returns the same as QHostInfo::localHostName().

    \sa QHostInfo::localDomainName, machineUniqueId()
 */
QString QSysInfo::machineHostName()
{
    // the hostname can change, so we can't cache it
#if defined(Q_OS_LINUX)
    // gethostname(3) on Linux just calls uname(2), so do it ourselves
    // and avoid a memcpy
    struct utsname u;
    if (uname(&u) == 0)
        return QString::fromLocal8Bit(u.nodename);
    return QString();
#else
#  ifdef Q_OS_WIN
    // Important: QtNetwork depends on machineHostName() initializing ws2_32.dll
    winsockInit();
#  endif

    char hostName[512];
    if (gethostname(hostName, sizeof(hostName)) == -1)
        return QString();
    hostName[sizeof(hostName) - 1] = '\0';
    return QString::fromLocal8Bit(hostName);
#endif
}
#endif // QT_BOOTSTRAPPED

enum {
    UuidStringLen = sizeof("00000000-0000-0000-0000-000000000000") - 1
};

/*!
    \since 5.11

    Returns a unique ID for this machine, if one can be determined. If no
    unique ID could be determined, this function returns an empty byte array.
    Unlike machineHostName(), the value returned by this function is likely
    globally unique.

    A unique ID is useful in network operations to identify this machine for an
    extended period of time, when the IP address could change or if this
    machine could have more than one IP address. For example, the ID could be
    used when communicating with a server or when storing device-specific data
    in shared network storage.

    Note that on some systems, this value will persist across reboots and on
    some it will not. Applications should not blindly depend on this fact
    without verifying the OS capabilities. In particular, on Linux systems,
    this ID is usually permanent and it matches the D-Bus machine ID, except
    for nodes without their own storage (replicated nodes).

    \sa machineHostName(), bootUniqueId()
*/
QByteArray QSysInfo::machineUniqueId()
{
#if defined(Q_OS_DARWIN) && __has_include(<IOKit/IOKitLib.h>)
    char uuid[UuidStringLen + 1];
    io_service_t service = IOServiceGetMatchingService(kIOMasterPortDefault, IOServiceMatching("IOPlatformExpertDevice"));
    QCFString stringRef = (CFStringRef)IORegistryEntryCreateCFProperty(service, CFSTR(kIOPlatformUUIDKey), kCFAllocatorDefault, 0);
    CFStringGetCString(stringRef, uuid, sizeof(uuid), kCFStringEncodingMacRoman);
    return QByteArray(uuid);
#elif defined(Q_OS_BSD4) && defined(KERN_HOSTUUID)
    char uuid[UuidStringLen + 1];
    size_t uuidlen = sizeof(uuid);
    int name[] = { CTL_KERN, KERN_HOSTUUID };
    if (sysctl(name, sizeof name / sizeof name[0], &uuid, &uuidlen, nullptr, 0) == 0
            && uuidlen == sizeof(uuid))
        return QByteArray(uuid, uuidlen - 1);
#elif defined(Q_OS_UNIX)
    // The modern name on Linux is /etc/machine-id, but that path is
    // unlikely to exist on non-Linux (non-systemd) systems. The old
    // path is more than enough.
    static const char fullfilename[] = "/usr/local/var/lib/dbus/machine-id";
    const char *firstfilename = fullfilename + sizeof("/usr/local") - 1;
    int fd = qt_safe_open(firstfilename, O_RDONLY);
    if (fd == -1 && errno == ENOENT)
        fd = qt_safe_open(fullfilename, O_RDONLY);

    if (fd != -1) {
        char buffer[32];    // 128 bits, hex-encoded
        qint64 len = qt_safe_read(fd, buffer, sizeof(buffer));
        qt_safe_close(fd);

        if (len != -1)
            return QByteArray(buffer, len);
    }
#elif defined(Q_OS_WIN)
    // Let's poke at the registry
    // ### Qt 6: Use new helpers from qwinregistry.cpp (once bootstrap builds are obsolete)
    HKEY key = NULL;
    if (RegOpenKeyEx(HKEY_LOCAL_MACHINE, L"SOFTWARE\\Microsoft\\Cryptography", 0, KEY_READ | KEY_WOW64_64KEY, &key)
            == ERROR_SUCCESS) {
        wchar_t buffer[UuidStringLen + 1];
        DWORD size = sizeof(buffer);
        bool ok = (RegQueryValueEx(key, L"MachineGuid", NULL, NULL, (LPBYTE)buffer, &size) ==
                   ERROR_SUCCESS);
        RegCloseKey(key);
        if (ok)
            return QStringView(buffer, (size - 1) / 2).toLatin1();
    }
#endif
    return QByteArray();
}

/*!
    \since 5.11

    Returns a unique ID for this machine's boot, if one can be determined. If
    no unique ID could be determined, this function returns an empty byte
    array. This value is expected to change after every boot and can be
    considered globally unique.

    This function is currently only implemented for Linux and Apple operating
    systems.

    \sa machineUniqueId()
*/
QByteArray QSysInfo::bootUniqueId()
{
#ifdef Q_OS_LINUX
    // use low-level API here for simplicity
    int fd = qt_safe_open("/proc/sys/kernel/random/boot_id", O_RDONLY);
    if (fd != -1) {
        char uuid[UuidStringLen];
        qint64 len = qt_safe_read(fd, uuid, sizeof(uuid));
        qt_safe_close(fd);
        if (len == UuidStringLen)
            return QByteArray(uuid, UuidStringLen);
    }
#elif defined(Q_OS_DARWIN)
    // "kern.bootsessionuuid" is only available by name
    char uuid[UuidStringLen + 1];
    size_t uuidlen = sizeof(uuid);
    if (sysctlbyname("kern.bootsessionuuid", uuid, &uuidlen, nullptr, 0) == 0
            && uuidlen == sizeof(uuid))
        return QByteArray(uuid, uuidlen - 1);
#endif
    return QByteArray();
};

/*!
    \macro void Q_ASSERT(bool test)
    \relates <QtGlobal>

    Prints a warning message containing the source code file name and
    line number if \a test is \c false.

    Q_ASSERT() is useful for testing pre- and post-conditions
    during development. It does nothing if \c QT_NO_DEBUG was defined
    during compilation.

    Example:

    \snippet code/src_corelib_global_qglobal.cpp 17

    If \c b is zero, the Q_ASSERT statement will output the following
    message using the qFatal() function:

    \snippet code/src_corelib_global_qglobal.cpp 18

    \sa Q_ASSERT_X(), qFatal(), {Debugging Techniques}
*/

/*!
    \macro void Q_ASSERT_X(bool test, const char *where, const char *what)
    \relates <QtGlobal>

    Prints the message \a what together with the location \a where,
    the source file name and line number if \a test is \c false.

    Q_ASSERT_X is useful for testing pre- and post-conditions during
    development. It does nothing if \c QT_NO_DEBUG was defined during
    compilation.

    Example:

    \snippet code/src_corelib_global_qglobal.cpp 19

    If \c b is zero, the Q_ASSERT_X statement will output the following
    message using the qFatal() function:

    \snippet code/src_corelib_global_qglobal.cpp 20

    \sa Q_ASSERT(), qFatal(), {Debugging Techniques}
*/

/*!
    \macro void Q_ASSUME(bool expr)
    \relates <QtGlobal>
    \since 5.0

    Causes the compiler to assume that \a expr is \c true. This macro is useful
    for improving code generation, by providing the compiler with hints about
    conditions that it would not otherwise know about. However, there is no
    guarantee that the compiler will actually use those hints.

    This macro could be considered a "lighter" version of \l{Q_ASSERT()}. While
    Q_ASSERT will abort the program's execution if the condition is \c false,
    Q_ASSUME will tell the compiler not to generate code for those conditions.
    Therefore, it is important that the assumptions always hold, otherwise
    undefined behaviour may occur.

    If \a expr is a constantly \c false condition, Q_ASSUME will tell the compiler
    that the current code execution cannot be reached. That is, Q_ASSUME(false)
    is equivalent to Q_UNREACHABLE().

    In debug builds the condition is enforced by an assert to facilitate debugging.

    \note Q_LIKELY() tells the compiler that the expression is likely, but not
    the only possibility. Q_ASSUME tells the compiler that it is the only
    possibility.

    \sa Q_ASSERT(), Q_UNREACHABLE(), Q_LIKELY()
*/

/*!
    \macro void Q_UNREACHABLE()
    \relates <QtGlobal>
    \since 5.0

    Tells the compiler that the current point cannot be reached by any
    execution, so it may optimize any code paths leading here as dead code, as
    well as code continuing from here.

    This macro is useful to mark impossible conditions. For example, given the
    following enum:

    \snippet code/src_corelib_global_qglobal.cpp qunreachable-enum

    One can write a switch table like so:

    \snippet code/src_corelib_global_qglobal.cpp qunreachable-switch

    The advantage of inserting Q_UNREACHABLE() at that point is that the
    compiler is told not to generate code for a shape variable containing that
    value. If the macro is missing, the compiler will still generate the
    necessary comparisons for that value. If the case label were removed, some
    compilers could produce a warning that some enum values were not checked.

    By using this macro in impossible conditions, code coverage may be improved
    as dead code paths may be eliminated.

    In debug builds the condition is enforced by an assert to facilitate debugging.

    \sa Q_ASSERT(), Q_ASSUME(), qFatal()
*/

/*!
    \macro void Q_FALLTHROUGH()
    \relates <QtGlobal>
    \since 5.8

    Can be used in switch statements at the end of case block to tell the compiler
    and other developers that that the lack of a break statement is intentional.

    This is useful since a missing break statement is often a bug, and some
    compilers can be configured to emit warnings when one is not found.

    \sa Q_UNREACHABLE()
*/

/*!
    \macro void Q_CHECK_PTR(void *pointer)
    \relates <QtGlobal>

    If \a pointer is \nullptr, prints a message containing the source
    code's file name and line number, saying that the program ran out
    of memory and aborts program execution. It throws \c std::bad_alloc instead
    if exceptions are enabled.

    Q_CHECK_PTR does nothing if \c QT_NO_DEBUG and \c QT_NO_EXCEPTIONS were
    defined during compilation. Therefore you must not use Q_CHECK_PTR to check
    for successful memory allocations because the check will be disabled in
    some cases.

    Example:

    \snippet code/src_corelib_global_qglobal.cpp 21

    \sa qWarning(), {Debugging Techniques}
*/

/*!
    \fn template <typename T> T *q_check_ptr(T *p)
    \relates <QtGlobal>

    Uses Q_CHECK_PTR on \a p, then returns \a p.

    This can be used as an inline version of Q_CHECK_PTR.
*/

/*!
    \macro const char* Q_FUNC_INFO()
    \relates <QtGlobal>

    Expands to a string that describe the function the macro resides in. How this string looks
    more specifically is compiler dependent. With GNU GCC it is typically the function signature,
    while with other compilers it might be the line and column number.

    Q_FUNC_INFO can be conveniently used with qDebug(). For example, this function:

    \snippet code/src_corelib_global_qglobal.cpp 22

    when instantiated with the integer type, will with the GCC compiler produce:

    \tt{const TInputType& myMin(const TInputType&, const TInputType&) [with TInputType = int] was called with value1: 3 value2: 4}

    If this macro is used outside a function, the behavior is undefined.
 */

/*!
    \internal
    The Q_CHECK_PTR macro calls this function if an allocation check
    fails.
*/
void qt_check_pointer(const char *n, int l) noexcept
{
    // make separate printing calls so that the first one may flush;
    // the second one could want to allocate memory (fputs prints a
    // newline and stderr auto-flushes).
    fputs("Out of memory", stderr);
    fprintf(stderr, "  in %s, line %d\n", n, l);

    std::terminate();
}

/*
   \internal
   Allows you to throw an exception without including <new>
   Called internally from Q_CHECK_PTR on certain OS combinations
*/
void qBadAlloc()
{
    QT_THROW(std::bad_alloc());
}

#ifndef QT_NO_EXCEPTIONS
/*
   \internal
   Allows you to call std::terminate() without including <exception>.
   Called internally from QT_TERMINATE_ON_EXCEPTION
*/
Q_NORETURN void qTerminate() noexcept
{
    std::terminate();
}
#endif

/*
  The Q_ASSERT macro calls this function when the test fails.
*/
void qt_assert(const char *assertion, const char *file, int line) noexcept
{
    QMessageLogger(file, line, nullptr).fatal("ASSERT: \"%s\" in file %s, line %d", assertion, file, line);
}

/*
  The Q_ASSERT_X macro calls this function when the test fails.
*/
void qt_assert_x(const char *where, const char *what, const char *file, int line) noexcept
{
    QMessageLogger(file, line, nullptr).fatal("ASSERT failure in %s: \"%s\", file %s, line %d", where, what, file, line);
}


/*
    Dijkstra's bisection algorithm to find the square root of an integer.
    Deliberately not exported as part of the Qt API, but used in both
    qsimplerichtext.cpp and qgfxraster_qws.cpp
*/
Q_CORE_EXPORT Q_DECL_CONST_FUNCTION unsigned int qt_int_sqrt(unsigned int n)
{
    // n must be in the range 0...UINT_MAX/2-1
    if (n >= (UINT_MAX >> 2)) {
        unsigned int r = 2 * qt_int_sqrt(n / 4);
        unsigned int r2 = r + 1;
        return (n >= r2 * r2) ? r2 : r;
    }
    uint h, p = 0, q = 1, r = n;
    while (q <= n)
        q <<= 2;
    while (q != 1) {
        q >>= 2;
        h = p + q;
        p >>= 1;
        if (r >= h) {
            p += q;
            r -= h;
        }
    }
    return p;
}

// In the C runtime on all platforms access to the environment is not thread-safe. We
// add thread-safety for the Qt wrappers.
static QBasicMutex environmentMutex;

/*
  Wraps tzset(), which accesses the environment, so should only be called while
  we hold the lock on the environment mutex.
*/
void qTzSet()
{
    const auto locker = qt_scoped_lock(environmentMutex);
#if defined(Q_OS_WIN)
    _tzset();
#else
    tzset();
#endif // Q_OS_WIN
}

/*
  Wrap mktime(), which is specified to behave as if it called tzset(), hence
  shares its implicit environment-dependence.
*/
time_t qMkTime(struct tm *when)
{
    const auto locker = qt_scoped_lock(environmentMutex);
    return mktime(when);
}

// Also specified to behave as if they call tzset():
// localtime() -- but not localtime_r(), which we use when threaded
// strftime() -- not used (except in tests)

/*!
    \relates <QtGlobal>
    \threadsafe

    Returns the value of the environment variable with name \a varName as a
    QByteArray. If no variable by that name is found in the environment, this
    function returns a default-constructed QByteArray.

    The Qt environment manipulation functions are thread-safe, but this
    requires that the C library equivalent functions like getenv and putenv are
    not directly called.

    To convert the data to a QString use QString::fromLocal8Bit().

    \note on desktop Windows, qgetenv() may produce data loss if the
    original string contains Unicode characters not representable in the
    ANSI encoding. Use qEnvironmentVariable() instead.
    On Unix systems, this function is lossless.

    \sa qputenv(), qEnvironmentVariable(), qEnvironmentVariableIsSet(),
    qEnvironmentVariableIsEmpty()
*/
QByteArray qgetenv(const char *varName)
{
    const auto locker = qt_scoped_lock(environmentMutex);
#ifdef Q_CC_MSVC
    size_t requiredSize = 0;
    QByteArray buffer;
    getenv_s(&requiredSize, 0, 0, varName);
    if (requiredSize == 0)
        return buffer;
    buffer.resize(int(requiredSize));
    getenv_s(&requiredSize, buffer.data(), requiredSize, varName);
    // requiredSize includes the terminating null, which we don't want.
    Q_ASSERT(buffer.endsWith('\0'));
    buffer.chop(1);
    return buffer;
#else
    return QByteArray(::getenv(varName));
#endif
}

/*!
    \fn QString qEnvironmentVariable(const char *varName, const QString &defaultValue)
    \fn QString qEnvironmentVariable(const char *varName)

    \relates <QtGlobal>
    \since 5.10

    These functions return the value of the environment variable, \a varName, as a
    QString. If no variable \a varName is found in the environment and \a defaultValue
    is provided, \a defaultValue is returned. Otherwise QString() is returned.

    The Qt environment manipulation functions are thread-safe, but this
    requires that the C library equivalent functions like getenv and putenv are
    not directly called.

    The following table describes how to choose between qgetenv() and
    qEnvironmentVariable():
    \table
      \header \li Condition         \li Recommendation
      \row
        \li Variable contains file paths or user text
        \li qEnvironmentVariable()
      \row
        \li Windows-specific code
        \li qEnvironmentVariable()
      \row
        \li Unix-specific code, destination variable is not QString and/or is
            used to interface with non-Qt APIs
        \li qgetenv()
      \row
        \li Destination variable is a QString
        \li qEnvironmentVariable()
      \row
        \li Destination variable is a QByteArray or std::string
        \li qgetenv()
    \endtable

    \note on Unix systems, this function may produce data loss if the original
    string contains arbitrary binary data that cannot be decoded by the locale
    codec. Use qgetenv() instead for that case. On Windows, this function is
    lossless.

    \note the variable name \a varName must contain only US-ASCII characters.

    \sa qputenv(), qgetenv(), qEnvironmentVariableIsSet(), qEnvironmentVariableIsEmpty()
*/
QString qEnvironmentVariable(const char *varName, const QString &defaultValue)
{
#if defined(Q_OS_WIN)
    const auto locker = qt_scoped_lock(environmentMutex);
    QVarLengthArray<wchar_t, 32> wname(int(strlen(varName)) + 1);
    for (int i = 0; i < wname.size(); ++i) // wname.size() is correct: will copy terminating null
        wname[i] = uchar(varName[i]);
    size_t requiredSize = 0;
    QString buffer;
    _wgetenv_s(&requiredSize, 0, 0, wname.data());
    if (requiredSize == 0)
        return defaultValue;
    buffer.resize(int(requiredSize));
    _wgetenv_s(&requiredSize, reinterpret_cast<wchar_t *>(buffer.data()), requiredSize,
               wname.data());
    // requiredSize includes the terminating null, which we don't want.
    Q_ASSERT(buffer.endsWith(QLatin1Char('\0')));
    buffer.chop(1);
    return buffer;
#else
    QByteArray value = qgetenv(varName);
    if (value.isNull())
        return defaultValue;
// duplicated in qfile.h (QFile::decodeName)
#if defined(Q_OS_DARWIN)
    return QString::fromUtf8(value).normalized(QString::NormalizationForm_C);
#else // other Unix
    return QString::fromLocal8Bit(value);
#endif
#endif
}

QString qEnvironmentVariable(const char *varName)
{
    return qEnvironmentVariable(varName, QString());
}

/*!
    \relates <QtGlobal>
    \since 5.1

    Returns whether the environment variable \a varName is empty.

    Equivalent to
    \snippet code/src_corelib_global_qglobal.cpp is-empty
    except that it's potentially much faster, and can't throw exceptions.

    \sa qgetenv(), qEnvironmentVariable(), qEnvironmentVariableIsSet()
*/
bool qEnvironmentVariableIsEmpty(const char *varName) noexcept
{
    const auto locker = qt_scoped_lock(environmentMutex);
#ifdef Q_CC_MSVC
    // we provide a buffer that can only hold the empty string, so
    // when the env.var isn't empty, we'll get an ERANGE error (buffer
    // too small):
    size_t dummy;
    char buffer = '\0';
    return getenv_s(&dummy, &buffer, 1, varName) != ERANGE;
#else
    const char * const value = ::getenv(varName);
    return !value || !*value;
#endif
}

/*!
    \relates <QtGlobal>
    \since 5.5

    Returns the numerical value of the environment variable \a varName.
    If \a ok is not null, sets \c{*ok} to \c true or \c false depending
    on the success of the conversion.

    Equivalent to
    \snippet code/src_corelib_global_qglobal.cpp to-int
    except that it's much faster, and can't throw exceptions.

    \note there's a limit on the length of the value, which is sufficient for
    all valid values of int, not counting leading zeroes or spaces. Values that
    are too long will either be truncated or this function will set \a ok to \c
    false.

    \sa qgetenv(), qEnvironmentVariable(), qEnvironmentVariableIsSet()
*/
int qEnvironmentVariableIntValue(const char *varName, bool *ok) noexcept
{
    static const int NumBinaryDigitsPerOctalDigit = 3;
    static const int MaxDigitsForOctalInt =
        (std::numeric_limits<uint>::digits + NumBinaryDigitsPerOctalDigit - 1) / NumBinaryDigitsPerOctalDigit;

    const auto locker = qt_scoped_lock(environmentMutex);
#ifdef Q_CC_MSVC
    // we provide a buffer that can hold any int value:
    char buffer[MaxDigitsForOctalInt + 2]; // +1 for NUL +1 for optional '-'
    size_t dummy;
    if (getenv_s(&dummy, buffer, sizeof buffer, varName) != 0) {
        if (ok)
            *ok = false;
        return 0;
    }
#else
    const char * const buffer = ::getenv(varName);
    if (!buffer || strlen(buffer) > MaxDigitsForOctalInt + 2) {
        if (ok)
            *ok = false;
        return 0;
    }
#endif
    bool ok_ = true;
    const char *endptr;
    const qlonglong value = qstrtoll(buffer, &endptr, 0, &ok_);

    // Keep the following checks in sync with QByteArray::toInt()
    if (!ok_) {
        if (ok)
            *ok = false;
        return 0;
    }

    if (*endptr != '\0') {
        while (ascii_isspace(*endptr))
            ++endptr;
    }

    if (*endptr != '\0') {
        // we stopped at a non-digit character after converting some digits
        if (ok)
            *ok = false;
        return 0;
    }

    if (int(value) != value) {
        if (ok)
            *ok = false;
        return 0;
    } else if (ok) {
        *ok = ok_;
    }
    return int(value);
}

/*!
    \relates <QtGlobal>
    \since 5.1

    Returns whether the environment variable \a varName is set.

    Equivalent to
    \snippet code/src_corelib_global_qglobal.cpp is-null
    except that it's potentially much faster, and can't throw exceptions.

    \sa qgetenv(), qEnvironmentVariable(), qEnvironmentVariableIsEmpty()
*/
bool qEnvironmentVariableIsSet(const char *varName) noexcept
{
    const auto locker = qt_scoped_lock(environmentMutex);
#ifdef Q_CC_MSVC
    size_t requiredSize = 0;
    (void)getenv_s(&requiredSize, 0, 0, varName);
    return requiredSize != 0;
#else
    return ::getenv(varName) != nullptr;
#endif
}

/*!
    \relates <QtGlobal>

    This function sets the \a value of the environment variable named
    \a varName. It will create the variable if it does not exist. It
    returns 0 if the variable could not be set.

    Calling qputenv with an empty value removes the environment variable on
    Windows, and makes it set (but empty) on Unix. Prefer using qunsetenv()
    for fully portable behavior.

    \note qputenv() was introduced because putenv() from the standard
    C library was deprecated in VC2005 (and later versions). qputenv()
    uses the replacement function in VC, and calls the standard C
    library's implementation on all other platforms.

    \sa qgetenv(), qEnvironmentVariable()
*/
bool qputenv(const char *varName, const QByteArray &value)
{
    const auto locker = qt_scoped_lock(environmentMutex);
#if defined(Q_CC_MSVC)
    return _putenv_s(varName, value.constData()) == 0;
#elif (defined(_POSIX_VERSION) && (_POSIX_VERSION-0) >= 200112L) || defined(Q_OS_HAIKU)
    // POSIX.1-2001 has setenv
    return setenv(varName, value.constData(), true) == 0;
#else
    QByteArray buffer(varName);
    buffer += '=';
    buffer += value;
    char *envVar = qstrdup(buffer.constData());
    int result = putenv(envVar);
    if (result != 0) // error. we have to delete the string.
        delete[] envVar;
    return result == 0;
#endif
}

/*!
    \relates <QtGlobal>

    This function deletes the variable \a varName from the environment.

    Returns \c true on success.

    \since 5.1

    \sa qputenv(), qgetenv(), qEnvironmentVariable()
*/
bool qunsetenv(const char *varName)
{
    const auto locker = qt_scoped_lock(environmentMutex);
#if defined(Q_CC_MSVC)
    return _putenv_s(varName, "") == 0;
#elif (defined(_POSIX_VERSION) && (_POSIX_VERSION-0) >= 200112L) || defined(Q_OS_BSD4) || defined(Q_OS_HAIKU)
    // POSIX.1-2001, BSD and Haiku have unsetenv
    return unsetenv(varName) == 0;
#elif defined(Q_CC_MINGW)
    // On mingw, putenv("var=") removes "var" from the environment
    QByteArray buffer(varName);
    buffer += '=';
    return putenv(buffer.constData()) == 0;
#else
    // Fallback to putenv("var=") which will insert an empty var into the
    // environment and leak it
    QByteArray buffer(varName);
    buffer += '=';
    char *envVar = qstrdup(buffer.constData());
    return putenv(envVar) == 0;
#endif
}

/*!
    \macro forever
    \relates <QtGlobal>

    This macro is provided for convenience for writing infinite
    loops.

    Example:

    \snippet code/src_corelib_global_qglobal.cpp 31

    It is equivalent to \c{for (;;)}.

    If you're worried about namespace pollution, you can disable this
    macro by adding the following line to your \c .pro file:

    \snippet code/src_corelib_global_qglobal.cpp 32

    \sa Q_FOREVER
*/

/*!
    \macro Q_FOREVER
    \relates <QtGlobal>

    Same as \l{forever}.

    This macro is available even when \c no_keywords is specified
    using the \c .pro file's \c CONFIG variable.

    \sa foreach()
*/

/*!
    \macro foreach(variable, container)
    \relates <QtGlobal>

    This macro is used to implement Qt's \c foreach loop. The \a
    variable parameter is a variable name or variable definition; the
    \a container parameter is a Qt container whose value type
    corresponds to the type of the variable. See \l{The foreach
    Keyword} for details.

    If you're worried about namespace pollution, you can disable this
    macro by adding the following line to your \c .pro file:

    \snippet code/src_corelib_global_qglobal.cpp 33

    \note Since Qt 5.7, the use of this macro is discouraged. It will
    be removed in a future version of Qt. Please use C++11 range-for,
    possibly with qAsConst(), as needed.

    \sa qAsConst()
*/

/*!
    \macro Q_FOREACH(variable, container)
    \relates <QtGlobal>

    Same as foreach(\a variable, \a container).

    This macro is available even when \c no_keywords is specified
    using the \c .pro file's \c CONFIG variable.

    \note Since Qt 5.7, the use of this macro is discouraged. It will
    be removed in a future version of Qt. Please use C++11 range-for,
    possibly with qAsConst(), as needed.

    \sa qAsConst()
*/

/*!
    \fn template <typename T> typename std::add_const<T>::type &qAsConst(T &t)
    \relates <QtGlobal>
    \since 5.7

    Returns \a t cast to \c{const T}.

    This function is a Qt implementation of C++17's std::as_const(),
    a cast function like std::move(). But while std::move() turns
    lvalues into rvalues, this function turns non-const lvalues into
    const lvalues. Like std::as_const(), it doesn't work on rvalues,
    because it cannot be efficiently implemented for rvalues without
    leaving dangling references.

    Its main use in Qt is to prevent implicitly-shared Qt containers
    from detaching:
    \snippet code/src_corelib_global_qglobal.cpp as-const-0

    Of course, in this case, you could (and probably should) have declared
    \c s as \c const in the first place:
    \snippet code/src_corelib_global_qglobal.cpp as-const-1
    but often that is not easily possible.

    It is important to note that qAsConst() does not copy its argument,
    it just performs a \c{const_cast<const T&>(t)}. This is also the reason
    why it is designed to fail for rvalues: The returned reference would go
    stale too soon. So while this works (but detaches the returned object):
    \snippet code/src_corelib_global_qglobal.cpp as-const-2

    this would not:
    \snippet code/src_corelib_global_qglobal.cpp as-const-3

    To prevent this construct from compiling (and failing at runtime), qAsConst() has
    a second, deleted, overload which binds to rvalues.
*/

/*!
    \fn template <typename T> void qAsConst(const T &&t)
    \relates <QtGlobal>
    \since 5.7
    \overload

    This overload is deleted to prevent a dangling reference in code like
    \snippet code/src_corelib_global_qglobal.cpp as-const-4
*/

/*!
    \fn template <typename T, typename U = T> T qExchange(T &obj, U &&newValue)
    \relates <QtGlobal>
    \since 5.14

    Replaces the value of \a obj with \a newValue and returns the old value of \a obj.

    This is Qt's implementation of std::exchange(). It differs from std::exchange()
    only in that it is \c constexpr already in C++14, and available on all supported
    compilers.

    Here is how to use qExchange() to implement move constructors:
    \code
    MyClass(MyClass &&other)
      : m_pointer{qExchange(other.m_pointer, nullptr)},
        m_int{qExchange(other.m_int, 0)},
        m_vector{std::move(other.m_vector)},
        ...
    \endcode

    For members of class type, we can use std::move(), as their move-constructor will
    do the right thing. But for scalar types such as raw pointers or integer type, move
    is the same as copy, which, particularly for pointers, is not what we expect. So, we
    cannot use std::move() for such types, but we can use std::exchange()/qExchange() to
    make sure the source object's member is already reset by the time we get to the
    initialization of our next data member, which might come in handy if the constructor
    exits with an exception.

    Here is how to use qExchange() to write a loop that consumes the collection it
    iterates over:
    \code
    for (auto &e : qExchange(collection, {})
        doSomethingWith(e);
    \endcode

    Which is equivalent to the following, much more verbose code:
    \code
    {
        auto tmp = std::move(collection);
        collection = {};                    // or collection.clear()
        for (auto &e : tmp)
            doSomethingWith(e);
    }                                       // destroys 'tmp'
    \endcode

    This is perfectly safe, as the for-loop keeps the result of qExchange() alive for as
    long as the loop runs, saving the declaration of a temporary variable. Be aware, though,
    that qExchange() returns a non-const object, so Qt containers may detach.
*/

/*!
    \macro QT_TR_NOOP(sourceText)
    \relates <QtGlobal>

    Marks the UTF-8 encoded string literal \a sourceText for delayed
    translation in the current context (class).

    The macro tells lupdate to collect the string, and expands to
    \a sourceText itself.

    Example:

    \snippet code/src_corelib_global_qglobal.cpp 34

    The macro QT_TR_NOOP_UTF8() is identical and obsolete; this applies
    to all other _UTF8 macros as well.

    \sa QT_TRANSLATE_NOOP(), {Internationalization with Qt}
*/

/*!
    \macro QT_TRANSLATE_NOOP(context, sourceText)
    \relates <QtGlobal>

    Marks the UTF-8 encoded string literal \a sourceText for delayed
    translation in the given \a context. The \a context is typically
    a class name and also needs to be specified as a string literal.

    The macro tells lupdate to collect the string, and expands to
    \a sourceText itself.

    Example:

    \snippet code/src_corelib_global_qglobal.cpp 35

    \sa QT_TR_NOOP(), QT_TRANSLATE_NOOP3(), {Internationalization with Qt}
*/

/*!
    \macro QT_TRANSLATE_NOOP3(context, sourceText, disambiguation)
    \relates <QtGlobal>
    \since 4.4

    Marks the UTF-8 encoded string literal \a sourceText for delayed
    translation in the given \a context with the given \a disambiguation.
    The \a context is typically a class and also needs to be specified
    as a string literal. The string literal \a disambiguation should be
    a short semantic tag to tell apart otherwise identical strings.

    The macro tells lupdate to collect the string, and expands to an
    anonymous struct of the two string literals passed as \a sourceText
    and \a disambiguation.

    Example:

    \snippet code/src_corelib_global_qglobal.cpp 36

    \sa QT_TR_NOOP(), QT_TRANSLATE_NOOP(), {Internationalization with Qt}
*/

/*!
    \macro QT_TR_N_NOOP(sourceText)
    \relates <QtGlobal>
    \since 5.12

    Marks the UTF-8 encoded string literal \a sourceText for numerator
    dependent delayed translation in the current context (class).

    The macro tells lupdate to collect the string, and expands to
    \a sourceText itself.

    The macro expands to \a sourceText.

    Example:

    \snippet code/src_corelib_global_qglobal.cpp qttrnnoop

    \sa QT_TR_NOOP, {Internationalization with Qt}
*/

/*!
    \macro QT_TRANSLATE_N_NOOP(context, sourceText)
    \relates <QtGlobal>
    \since 5.12

    Marks the UTF-8 encoded string literal \a sourceText for numerator
    dependent delayed translation in the given \a context.
    The \a context is typically a class name and also needs to be
    specified as a string literal.

    The macro tells lupdate to collect the string, and expands to
    \a sourceText itself.

    Example:

    \snippet code/src_corelib_global_qglobal.cpp qttranslatennoop

    \sa QT_TRANSLATE_NOOP(), QT_TRANSLATE_N_NOOP3(),
    {Internationalization with Qt}
*/

/*!
    \macro QT_TRANSLATE_N_NOOP3(context, sourceText, comment)
    \relates <QtGlobal>
    \since 5.12

    Marks the UTF-8 encoded string literal \a sourceText for numerator
    dependent delayed translation in the given \a context with the given
    \a comment.
    The \a context is typically a class and also needs to be specified
    as a string literal. The string literal \a comment should be
    a short semantic tag to tell apart otherwise identical strings.

    The macro tells lupdate to collect the string, and expands to an
    anonymous struct of the two string literals passed as \a sourceText
    and \a comment.

    Example:

    \snippet code/src_corelib_global_qglobal.cpp qttranslatennoop3

    \sa QT_TR_NOOP(), QT_TRANSLATE_NOOP(), QT_TRANSLATE_NOOP3(),
    {Internationalization with Qt}
*/

/*!
    \fn QString qtTrId(const char *id, int n = -1)
    \relates <QtGlobal>
    \reentrant
    \since 4.6

    \brief The qtTrId function finds and returns a translated string.

    Returns a translated string identified by \a id.
    If no matching string is found, the id itself is returned. This
    should not happen under normal conditions.

    If \a n >= 0, all occurrences of \c %n in the resulting string
    are replaced with a decimal representation of \a n. In addition,
    depending on \a n's value, the translation text may vary.

    Meta data and comments can be passed as documented for QObject::tr().
    In addition, it is possible to supply a source string template like that:

    \tt{//% <C string>}

    or

    \tt{\\begincomment% <C string> \\endcomment}

    Example:

    \snippet code/src_corelib_global_qglobal.cpp qttrid

    Creating QM files suitable for use with this function requires passing
    the \c -idbased option to the \c lrelease tool.

    \warning This method is reentrant only if all translators are
    installed \e before calling this method. Installing or removing
    translators while performing translations is not supported. Doing
    so will probably result in crashes or other undesirable behavior.

    \sa QObject::tr(), QCoreApplication::translate(), {Internationalization with Qt}
*/

/*!
    \macro QT_TRID_NOOP(id)
    \relates <QtGlobal>
    \since 4.6

    \brief The QT_TRID_NOOP macro marks an id for dynamic translation.

    The only purpose of this macro is to provide an anchor for attaching
    meta data like to qtTrId().

    The macro expands to \a id.

    Example:

    \snippet code/src_corelib_global_qglobal.cpp qttrid_noop

    \sa qtTrId(), {Internationalization with Qt}
*/

/*!
    \macro Q_LIKELY(expr)
    \relates <QtGlobal>
    \since 4.8

    \brief Hints to the compiler that the enclosed condition, \a expr, is
    likely to evaluate to \c true.

    Use of this macro can help the compiler to optimize the code.

    Example:

    \snippet code/src_corelib_global_qglobal.cpp qlikely

    \sa Q_UNLIKELY()
*/

/*!
    \macro Q_UNLIKELY(expr)
    \relates <QtGlobal>
    \since 4.8

    \brief Hints to the compiler that the enclosed condition, \a expr, is
    likely to evaluate to \c false.

    Use of this macro can help the compiler to optimize the code.

    Example:

    \snippet code/src_corelib_global_qglobal.cpp qunlikely

    \sa Q_LIKELY()
*/

/*!
    \macro QT_POINTER_SIZE
    \relates <QtGlobal>

    Expands to the size of a pointer in bytes (4 or 8). This is
    equivalent to \c sizeof(void *) but can be used in a preprocessor
    directive.
*/

/*!
    \macro const char *qPrintable(const QString &str)
    \relates <QtGlobal>

    Returns \a str as a \c{const char *}. This is equivalent to
    \a{str}.toLocal8Bit().constData().

    The char pointer will be invalid after the statement in which
    qPrintable() is used. This is because the array returned by
    QString::toLocal8Bit() will fall out of scope.

    \note qDebug(), qInfo(), qWarning(), qCritical(), qFatal() expect
    %s arguments to be UTF-8 encoded, while qPrintable() converts to
    local 8-bit encoding. Therefore qUtf8Printable() should be used
    for logging strings instead of qPrintable().

    \sa qUtf8Printable()
*/

/*!
    \macro const char *qUtf8Printable(const QString &str)
    \relates <QtGlobal>
    \since 5.4

    Returns \a str as a \c{const char *}. This is equivalent to
    \a{str}.toUtf8().constData().

    The char pointer will be invalid after the statement in which
    qUtf8Printable() is used. This is because the array returned by
    QString::toUtf8() will fall out of scope.

    Example:

    \snippet code/src_corelib_global_qglobal.cpp 37

    \sa qPrintable(), qDebug(), qInfo(), qWarning(), qCritical(), qFatal()
*/

/*!
    \macro const wchar_t *qUtf16Printable(const QString &str)
    \relates <QtGlobal>
    \since 5.7

    Returns \a str as a \c{const ushort *}, but cast to a \c{const wchar_t *}
    to avoid warnings. This is equivalent to \a{str}.utf16() plus some casting.

    The only useful thing you can do with the return value of this macro is to
    pass it to QString::asprintf() for use in a \c{%ls} conversion. In particular,
    the return value is \e{not} a valid \c{const wchar_t*}!

    In general, the pointer will be invalid after the statement in which
    qUtf16Printable() is used. This is because the pointer may have been
    obtained from a temporary expression, which will fall out of scope.

    Example:

    \snippet code/src_corelib_global_qglobal.cpp qUtf16Printable

    \sa qPrintable(), qDebug(), qInfo(), qWarning(), qCritical(), qFatal()
*/

/*!
    \macro Q_DECLARE_TYPEINFO(Type, Flags)
    \relates <QtGlobal>

    You can use this macro to specify information about a custom type
    \a Type. With accurate type information, Qt's \l{Container Classes}
    {generic containers} can choose appropriate storage methods and
    algorithms.

    \a Flags can be one of the following:

    \list
    \li \c Q_PRIMITIVE_TYPE specifies that \a Type is a POD (plain old
       data) type with no constructor or destructor, and for which memcpy()ing
       creates a valid independent copy of the object.
    \li \c Q_RELOCATABLE_TYPE specifies that \a Type has a constructor
       and/or a destructor but can be moved in memory using \c
       memcpy().
    \li \c Q_MOVABLE_TYPE is the same as \c Q_RELOCATABLE_TYPE. Prefer to use
        \c Q_RELOCATABLE_TYPE in new code. Note: despite the name, this
        has nothing to do with move constructors or C++ move semantics.
    \li \c Q_COMPLEX_TYPE (the default) specifies that \a Type has
       constructors and/or a destructor and that it may not be moved
       in memory.
    \endlist

    Example of a "primitive" type:

    \snippet code/src_corelib_global_qglobal.cpp 38

    An example of a non-POD "primitive" type is QUuid: Even though
    QUuid has constructors (and therefore isn't POD), every bit
    pattern still represents a valid object, and memcpy() can be used
    to create a valid independent copy of a QUuid object.

    Example of a relocatable type:

    \snippet code/src_corelib_global_qglobal.cpp 39

    Qt will try to detect the class of a type using
    \l {https://en.cppreference.com/w/cpp/types/is_trivial} {std::is_trivial_v<T>}
    to indentify primitive
    types and it will require both
    \l {https://en.cppreference.com/w/cpp/types/is_trivially_copyable} {std::is_trivially_copyable_v<T>}
    and
    \l {https://en.cppreference.com/w/cpp/types/is_destructible} {std::is_trivially_destructible_v<T>}
    to identify relocatable types.
    Use this macro to tune the behavior.
    For instance many types would be candidates for Q_RELOCATABLE_TYPE despite
    not being trivially-copyable.
*/

/*!
    \macro Q_UNUSED(name)
    \relates <QtGlobal>

    Indicates to the compiler that the parameter with the specified
    \a name is not used in the body of a function. This can be used to
    suppress compiler warnings while allowing functions to be defined
    with meaningful parameter names in their signatures.
*/

struct QInternal_CallBackTable
{
    QList<QList<qInternalCallback>> callbacks;
};

Q_GLOBAL_STATIC(QInternal_CallBackTable, global_callback_table)

bool QInternal::registerCallback(Callback cb, qInternalCallback callback)
{
    if (unsigned(cb) < unsigned(QInternal::LastCallback)) {
        QInternal_CallBackTable *cbt = global_callback_table();
        cbt->callbacks.resize(cb + 1);
        cbt->callbacks[cb].append(callback);
        return true;
    }
    return false;
}

bool QInternal::unregisterCallback(Callback cb, qInternalCallback callback)
{
    if (unsigned(cb) < unsigned(QInternal::LastCallback)) {
        if (global_callback_table.exists()) {
            QInternal_CallBackTable *cbt = global_callback_table();
            return cbt->callbacks[cb].removeAll(callback) > 0;
        }
    }
    return false;
}

bool QInternal::activateCallbacks(Callback cb, void **parameters)
{
    Q_ASSERT_X(cb >= 0, "QInternal::activateCallback()", "Callback id must be a valid id");

    if (!global_callback_table.exists())
        return false;

    QInternal_CallBackTable *cbt = &(*global_callback_table);
    if (cbt && cb < cbt->callbacks.size()) {
        QList<qInternalCallback> callbacks = cbt->callbacks[cb];
        bool ret = false;
        for (int i = 0; i < callbacks.size(); ++i)
            ret |= (callbacks.at(i))(parameters);
        return ret;
    }
    return false;
}

/*!
    \macro Q_BYTE_ORDER
    \relates <QtGlobal>

    This macro can be used to determine the byte order your system
    uses for storing data in memory. i.e., whether your system is
    little-endian or big-endian. It is set by Qt to one of the macros
    Q_LITTLE_ENDIAN or Q_BIG_ENDIAN. You normally won't need to worry
    about endian-ness, but you might, for example if you need to know
    which byte of an integer or UTF-16 character is stored in the
    lowest address. Endian-ness is important in networking, where
    computers with different values for Q_BYTE_ORDER must pass data
    back and forth.

    Use this macro as in the following examples.

    \snippet code/src_corelib_global_qglobal.cpp 40

    \sa Q_BIG_ENDIAN, Q_LITTLE_ENDIAN
*/

/*!
    \macro Q_LITTLE_ENDIAN
    \relates <QtGlobal>

    This macro represents a value you can compare to the macro
    Q_BYTE_ORDER to determine the endian-ness of your system.  In a
    little-endian system, the least significant byte is stored at the
    lowest address. The other bytes follow in increasing order of
    significance.

    \snippet code/src_corelib_global_qglobal.cpp 41

    \sa Q_BYTE_ORDER, Q_BIG_ENDIAN
*/

/*!
    \macro Q_BIG_ENDIAN
    \relates <QtGlobal>

    This macro represents a value you can compare to the macro
    Q_BYTE_ORDER to determine the endian-ness of your system.  In a
    big-endian system, the most significant byte is stored at the
    lowest address. The other bytes follow in decreasing order of
    significance.

    \snippet code/src_corelib_global_qglobal.cpp 42

    \sa Q_BYTE_ORDER, Q_LITTLE_ENDIAN
*/

/*!
    \macro QT_NAMESPACE
    \internal

    If this macro is defined to \c ns all Qt classes are put in a namespace
    called \c ns. Also, moc will output code putting metaobjects etc.
    into namespace \c ns.

    \sa QT_BEGIN_NAMESPACE, QT_END_NAMESPACE,
    QT_PREPEND_NAMESPACE, QT_USE_NAMESPACE,
    QT_BEGIN_INCLUDE_NAMESPACE, QT_END_INCLUDE_NAMESPACE,
    QT_BEGIN_MOC_NAMESPACE, QT_END_MOC_NAMESPACE,
*/

/*!
    \macro QT_PREPEND_NAMESPACE(identifier)
    \internal

    This macro qualifies \a identifier with the full namespace.
    It expands to \c{::QT_NAMESPACE::identifier} if \c QT_NAMESPACE is defined
    and only \a identifier otherwise.

    \sa QT_NAMESPACE
*/

/*!
    \macro QT_USE_NAMESPACE
    \internal

    This macro expands to using QT_NAMESPACE if QT_NAMESPACE is defined
    and nothing otherwise.

    \sa QT_NAMESPACE
*/

/*!
    \macro QT_BEGIN_NAMESPACE
    \internal

    This macro expands to

    \snippet code/src_corelib_global_qglobal.cpp begin namespace macro

    if \c QT_NAMESPACE is defined and nothing otherwise. If should always
    appear in the file-level scope and be followed by \c QT_END_NAMESPACE
    at the same logical level with respect to preprocessor conditionals
    in the same file.

    As a rule of thumb, \c QT_BEGIN_NAMESPACE should appear in all Qt header
    and Qt source files after the last \c{#include} line and before the first
    declaration.

    If that rule can't be followed because, e.g., \c{#include} lines and
    declarations are wildly mixed, place \c QT_BEGIN_NAMESPACE before
    the first declaration and wrap the \c{#include} lines in
    \c QT_BEGIN_INCLUDE_NAMESPACE and \c QT_END_INCLUDE_NAMESPACE.

    When using the \c QT_NAMESPACE feature in user code
    (e.g., when building plugins statically linked to Qt) where
    the user code is not intended to go into the \c QT_NAMESPACE
    namespace, all forward declarations of Qt classes need to
    be wrapped in \c QT_BEGIN_NAMESPACE and \c QT_END_NAMESPACE.
    After that, a \c QT_USE_NAMESPACE should follow.
    No further changes should be needed.

    \sa QT_NAMESPACE
*/

/*!
    \macro QT_END_NAMESPACE
    \internal

    This macro expands to

    \snippet code/src_corelib_global_qglobal.cpp end namespace macro

    if \c QT_NAMESPACE is defined and nothing otherwise. It is used to cancel
    the effect of \c QT_BEGIN_NAMESPACE.

    If a source file ends with a \c{#include} directive that includes a moc file,
    \c QT_END_NAMESPACE should be placed before that \c{#include}.

    \sa QT_NAMESPACE
*/

/*!
    \macro QT_BEGIN_INCLUDE_NAMESPACE
    \internal

    This macro is equivalent to \c QT_END_NAMESPACE.
    It only serves as syntactic sugar and is intended
    to be used before #include lines within a
    \c QT_BEGIN_NAMESPACE ... \c QT_END_NAMESPACE block.

    \sa QT_NAMESPACE
*/

/*!
    \macro QT_END_INCLUDE_NAMESPACE
    \internal

    This macro is equivalent to \c QT_BEGIN_NAMESPACE.
    It only serves as syntactic sugar and is intended
    to be used after #include lines within a
    \c QT_BEGIN_NAMESPACE ... \c QT_END_NAMESPACE block.

    \sa QT_NAMESPACE
*/

/*!
    \macro QT_BEGIN_MOC_NAMESPACE
    \internal

    This macro is output by moc at the beginning of
    moc files. It is equivalent to \c QT_USE_NAMESPACE.

    \sa QT_NAMESPACE
*/

/*!
    \macro QT_END_MOC_NAMESPACE
    \internal

    This macro is output by moc at the beginning of
    moc files. It expands to nothing.

    \sa QT_NAMESPACE
*/

/*!
 \fn bool qFuzzyCompare(double p1, double p2)
 \relates <QtGlobal>
 \since 4.4
 \threadsafe

 Compares the floating point value \a p1 and \a p2 and
 returns \c true if they are considered equal, otherwise \c false.

 Note that comparing values where either \a p1 or \a p2 is 0.0 will not work,
 nor does comparing values where one of the values is NaN or infinity.
 If one of the values is always 0.0, use qFuzzyIsNull instead. If one of the
 values is likely to be 0.0, one solution is to add 1.0 to both values.

 \snippet code/src_corelib_global_qglobal.cpp 46

 The two numbers are compared in a relative way, where the
 exactness is stronger the smaller the numbers are.
 */

/*!
 \fn bool qFuzzyCompare(float p1, float p2)
 \relates <QtGlobal>
 \since 4.4
 \threadsafe

 Compares the floating point value \a p1 and \a p2 and
 returns \c true if they are considered equal, otherwise \c false.

 The two numbers are compared in a relative way, where the
 exactness is stronger the smaller the numbers are.
 */

/*!
 \fn bool qFuzzyIsNull(double d)
 \relates <QtGlobal>
 \since 4.4
 \threadsafe

 Returns true if the absolute value of \a d is within 0.000000000001 of 0.0.
*/

/*!
 \fn bool qFuzzyIsNull(float f)
 \relates <QtGlobal>
 \since 4.4
 \threadsafe

 Returns true if the absolute value of \a f is within 0.00001f of 0.0.
*/

/*!
    \macro QT_REQUIRE_VERSION(int argc, char **argv, const char *version)
    \relates <QtGlobal>

    This macro can be used to ensure that the application is run
    against a recent enough version of Qt. This is especially useful
    if your application depends on a specific bug fix introduced in a
    bug-fix release (e.g., 4.0.2).

    The \a argc and \a argv parameters are the \c main() function's
    \c argc and \c argv parameters. The \a version parameter is a
    string literal that specifies which version of Qt the application
    requires (e.g., "4.0.2").

    Example:

    \snippet code/src_gui_dialogs_qmessagebox.cpp 4
*/

/*!
    \macro Q_DECL_EXPORT
    \relates <QtGlobal>

    This macro marks a symbol for shared library export (see
     \l{sharedlibrary.html}{Creating Shared Libraries}).

    \sa Q_DECL_IMPORT
*/

/*!
    \macro Q_DECL_IMPORT
    \relates <QtGlobal>

    This macro declares a symbol to be an import from a shared library (see
    \l{sharedlibrary.html}{Creating Shared Libraries}).

    \sa Q_DECL_EXPORT
*/

/*!
    \macro Q_DECL_CONSTEXPR
    \relates <QtGlobal>

    This macro can be used to declare variable that should be constructed at compile-time,
    or an inline function that can be computed at compile-time.

    It expands to "constexpr" if your compiler supports that C++11 keyword, or to nothing
    otherwise.

    \sa Q_DECL_RELAXED_CONSTEXPR
*/

/*!
    \macro Q_DECL_RELAXED_CONSTEXPR
    \relates <QtGlobal>

    This macro can be used to declare an inline function that can be computed
    at compile-time according to the relaxed rules from C++14.

    It expands to "constexpr" if your compiler supports C++14 relaxed constant
    expressions, or to nothing otherwise.

    \sa Q_DECL_CONSTEXPR
*/

/*!
    \macro qDebug(const char *message, ...)
    \relates <QtGlobal>
    \threadsafe

    Calls the message handler with the debug message \a message. If no
    message handler has been installed, the message is printed to
    stderr. Under Windows the message is sent to the console, if it is a
    console application; otherwise, it is sent to the debugger. On QNX, the
    message is sent to slogger2. This function does nothing if \c QT_NO_DEBUG_OUTPUT
    was defined during compilation.

    If you pass the function a format string and a list of arguments,
    it works in similar way to the C printf() function. The format
    should be a Latin-1 string.

    Example:

    \snippet code/src_corelib_global_qglobal.cpp 24

    If you include \c <QtDebug>, a more convenient syntax is also
    available:

    \snippet code/src_corelib_global_qglobal.cpp 25

    With this syntax, the function returns a QDebug object that is
    configured to use the QtDebugMsg message type. It automatically
    puts a single space between each item, and outputs a newline at
    the end. It supports many C++ and Qt types.

    To suppress the output at run-time, install your own message handler
    with qInstallMessageHandler().

    \sa qInfo(), qWarning(), qCritical(), qFatal(), qInstallMessageHandler(),
        {Debugging Techniques}
*/

/*!
    \macro qInfo(const char *message, ...)
    \relates <QtGlobal>
    \threadsafe
    \since 5.5

    Calls the message handler with the informational message \a message. If no
    message handler has been installed, the message is printed to
    stderr. Under Windows, the message is sent to the console, if it is a
    console application; otherwise, it is sent to the debugger. On QNX the
    message is sent to slogger2. This function does nothing if \c QT_NO_INFO_OUTPUT
    was defined during compilation.

    If you pass the function a format string and a list of arguments,
    it works in similar way to the C printf() function. The format
    should be a Latin-1 string.

    Example:

    \snippet code/src_corelib_global_qglobal.cpp qInfo_printf

    If you include \c <QtDebug>, a more convenient syntax is also
    available:

    \snippet code/src_corelib_global_qglobal.cpp qInfo_stream

    With this syntax, the function returns a QDebug object that is
    configured to use the QtInfoMsg message type. It automatically
    puts a single space between each item, and outputs a newline at
    the end. It supports many C++ and Qt types.

    To suppress the output at run-time, install your own message handler
    with qInstallMessageHandler().

    \sa qDebug(), qWarning(), qCritical(), qFatal(), qInstallMessageHandler(),
        {Debugging Techniques}
*/

/*!
    \macro qWarning(const char *message, ...)
    \relates <QtGlobal>
    \threadsafe

    Calls the message handler with the warning message \a message. If no
    message handler has been installed, the message is printed to
    stderr. Under Windows, the message is sent to the debugger.
    On QNX the message is sent to slogger2. This
    function does nothing if \c QT_NO_WARNING_OUTPUT was defined
    during compilation; it exits if at the nth warning corresponding to the
    counter in environment variable \c QT_FATAL_WARNINGS. That is, if the
    environment variable contains the value 1, it will exit on the 1st message;
    if it contains the value 10, it will exit on the 10th message. Any
    non-numeric value is equivalent to 1.

    This function takes a format string and a list of arguments,
    similar to the C printf() function. The format should be a Latin-1
    string.

    Example:
    \snippet code/src_corelib_global_qglobal.cpp 26

    If you include <QtDebug>, a more convenient syntax is
    also available:

    \snippet code/src_corelib_global_qglobal.cpp 27

    This syntax inserts a space between each item, and
    appends a newline at the end.

    To suppress the output at runtime, install your own message handler
    with qInstallMessageHandler().

    \sa qDebug(), qInfo(), qCritical(), qFatal(), qInstallMessageHandler(),
        {Debugging Techniques}
*/

/*!
    \macro qCritical(const char *message, ...)
    \relates <QtGlobal>
    \threadsafe

    Calls the message handler with the critical message \a message. If no
    message handler has been installed, the message is printed to
    stderr. Under Windows, the message is sent to the debugger.
    On QNX the message is sent to slogger2.

    It exits if the environment variable QT_FATAL_CRITICALS is not empty.

    This function takes a format string and a list of arguments,
    similar to the C printf() function. The format should be a Latin-1
    string.

    Example:
    \snippet code/src_corelib_global_qglobal.cpp 28

    If you include <QtDebug>, a more convenient syntax is
    also available:

    \snippet code/src_corelib_global_qglobal.cpp 29

    A space is inserted between the items, and a newline is
    appended at the end.

    To suppress the output at runtime, install your own message handler
    with qInstallMessageHandler().

    \sa qDebug(), qInfo(), qWarning(), qFatal(), qInstallMessageHandler(),
        {Debugging Techniques}
*/

/*!
    \macro qFatal(const char *message, ...)
    \relates <QtGlobal>

    Calls the message handler with the fatal message \a message. If no
    message handler has been installed, the message is printed to
    stderr. Under Windows, the message is sent to the debugger.
    On QNX the message is sent to slogger2.

    If you are using the \b{default message handler} this function will
    abort to create a core dump. On Windows, for debug builds,
    this function will report a _CRT_ERROR enabling you to connect a debugger
    to the application.

    This function takes a format string and a list of arguments,
    similar to the C printf() function.

    Example:
    \snippet code/src_corelib_global_qglobal.cpp 30

    To suppress the output at runtime, install your own message handler
    with qInstallMessageHandler().

    \sa qDebug(), qInfo(), qWarning(), qCritical(), qInstallMessageHandler(),
        {Debugging Techniques}
*/

/*!
    \macro qMove(x)
    \relates <QtGlobal>
    \obsolete

    Use \c std::move instead.

    It expands to "std::move".

    qMove takes an rvalue reference to its parameter \a x, and converts it to an xvalue.
*/

/*!
    \macro Q_DECL_NOTHROW
    \relates <QtGlobal>
    \since 5.0

    This macro marks a function as never throwing, under no
    circumstances. If the function does nevertheless throw, the
    behaviour is undefined.

    The macro expands to either "throw()", if that has some benefit on
    the compiler, or to C++11 noexcept, if available, or to nothing
    otherwise.

    If you need C++11 noexcept semantics, don't use this macro, use
    Q_DECL_NOEXCEPT/Q_DECL_NOEXCEPT_EXPR instead.

    \sa Q_DECL_NOEXCEPT, Q_DECL_NOEXCEPT_EXPR()
*/

/*!
    \macro QT_TERMINATE_ON_EXCEPTION(expr)
    \relates <QtGlobal>
    \internal

    In general, use of the Q_DECL_NOEXCEPT macro is preferred over
    Q_DECL_NOTHROW, because it exhibits well-defined behavior and
    supports the more powerful Q_DECL_NOEXCEPT_EXPR variant. However,
    use of Q_DECL_NOTHROW has the advantage that Windows builds
    benefit on a wide range or compiler versions that do not yet
    support the C++11 noexcept feature.

    It may therefore be beneficial to use Q_DECL_NOTHROW and emulate
    the C++11 behavior manually with an embedded try/catch.

    Qt provides the QT_TERMINATE_ON_EXCEPTION(expr) macro for this
    purpose. It either expands to \c expr (if Qt is compiled without
    exception support or the compiler supports C++11 noexcept
    semantics) or to
    \snippet code/src_corelib_global_qglobal.cpp qterminate
    otherwise.

    Since this macro expands to just \c expr if the compiler supports
    C++11 noexcept, expecting the compiler to take over responsibility
    of calling std::terminate() in that case, it should not be used
    outside Q_DECL_NOTHROW functions.

    \sa Q_DECL_NOEXCEPT, Q_DECL_NOTHROW, qTerminate()
*/

/*!
    \macro Q_DECL_NOEXCEPT
    \relates <QtGlobal>
    \since 5.0

    This macro marks a function as never throwing. If the function
    does nevertheless throw, the behaviour is defined:
    std::terminate() is called.

    The macro expands to C++11 noexcept, if available, or to nothing
    otherwise.

    If you need the operator version of C++11 noexcept, use
    Q_DECL_NOEXCEPT_EXPR(x).

    If you don't need C++11 noexcept semantics, e.g. because your
    function can't possibly throw, don't use this macro, use
    Q_DECL_NOTHROW instead.

    \sa Q_DECL_NOTHROW, Q_DECL_NOEXCEPT_EXPR()
*/

/*!
    \macro Q_DECL_NOEXCEPT_EXPR(x)
    \relates <QtGlobal>
    \since 5.0

    This macro marks a function as non-throwing if \a x is \c true. If
    the function does nevertheless throw, the behaviour is defined:
    std::terminate() is called.

    The macro expands to C++11 noexcept(x), if available, or to
    nothing otherwise.

    If you need the always-true version of C++11 noexcept, use
    Q_DECL_NOEXCEPT.

    If you don't need C++11 noexcept semantics, e.g. because your
    function can't possibly throw, don't use this macro, use
    Q_DECL_NOTHROW instead.

    \sa Q_DECL_NOTHROW, Q_DECL_NOEXCEPT
*/

/*!
    \macro Q_DECL_OVERRIDE
    \since 5.0
    \obsolete
    \relates <QtGlobal>

    This macro can be used to declare an overriding virtual
    function. Use of this markup will allow the compiler to generate
    an error if the overriding virtual function does not in fact
    override anything.

    It expands to "override".

    The macro goes at the end of the function, usually after the
    \c{const}, if any:
    \snippet code/src_corelib_global_qglobal.cpp qdecloverride

    \sa Q_DECL_FINAL
*/

/*!
    \macro Q_DECL_FINAL
    \since 5.0
    \obsolete
    \relates <QtGlobal>

    This macro can be used to declare an overriding virtual or a class
    as "final", with Java semantics. Further-derived classes can then
    no longer override this virtual function, or inherit from this
    class, respectively.

    It expands to "final".

    The macro goes at the end of the function, usually after the
    \c{const}, if any:
    \snippet code/src_corelib_global_qglobal.cpp qdeclfinal-1

    For classes, it goes in front of the \c{:} in the class
    definition, if any:
    \snippet code/src_corelib_global_qglobal.cpp qdeclfinal-2

    \sa Q_DECL_OVERRIDE
*/

/*!
    \macro Q_FORWARD_DECLARE_OBJC_CLASS(classname)
    \since 5.2
    \relates <QtGlobal>

    Forward-declares an Objective-C \a classname in a manner such that it can be
    compiled as either Objective-C or C++.

    This is primarily intended for use in header files that may be included by
    both Objective-C and C++ source files.
*/

/*!
    \macro Q_FORWARD_DECLARE_CF_TYPE(type)
    \since 5.2
    \relates <QtGlobal>

    Forward-declares a Core Foundation \a type. This includes the actual
    type and the ref type. For example, Q_FORWARD_DECLARE_CF_TYPE(CFString)
    declares __CFString and CFStringRef.
*/

/*!
    \macro Q_FORWARD_DECLARE_MUTABLE_CF_TYPE(type)
    \since 5.2
    \relates <QtGlobal>

    Forward-declares a mutable Core Foundation \a type. This includes the actual
    type and the ref type. For example, Q_FORWARD_DECLARE_MUTABLE_CF_TYPE(CFMutableString)
    declares __CFMutableString and CFMutableStringRef.
*/

QT_END_NAMESPACE
