qsysinfo.cpp

Go to the documentation of this file.

// Copyright (C) 2022 The Qt Company Ltd.
// Copyright (C) 2022 Intel Corporation.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
 
#include "qsysinfo.h"
 
#include <QtCore/qbytearray.h>
#include <QtCore/qoperatingsystemversion.h>
#include <QtCore/qstring.h>
 
#include <private/qoperatingsystemversion_p.h>
 
#ifdef Q_OS_UNIX
#  include <sys/utsname.h>
#  include <private/qcore_unix_p.h>
#endif
 
#ifdef Q_OS_ANDROID
#include <QtCore/private/qjnihelpers_p.h>
#include <qjniobject.h>
#endif
 
#if defined(Q_OS_SOLARIS)
#  include <sys/systeminfo.h>
#endif
 
#if defined(Q_OS_DARWIN)
#  include "qnamespace.h"
#  include <private/qcore_mac_p.h>
#  if __has_include(<IOKit/IOKitLib.h>)
#    include <IOKit/IOKitLib.h>
#  endif
#endif
 
#ifdef Q_OS_BSD4
#  include <sys/sysctl.h>
#endif
 
#if defined(Q_OS_WIN) || defined(Q_OS_CYGWIN)
#  include "qoperatingsystemversion_win_p.h"
#  include "private/qwinregistry_p.h"
#  include "qt_windows.h"
#endif // Q_OS_WIN || Q_OS_CYGWIN
 
#include "archdetect.cpp"
 
QT_BEGIN_NAMESPACE
 
using namespace Qt::StringLiterals;
 
#if defined(Q_OS_DARWIN)
 
static const char *osVer_helper(QOperatingSystemVersion version = QOperatingSystemVersion::current())
{
#ifdef Q_OS_MACOS
    if (version.majorVersion() == 13)
        return "Ventura";
    if (version.majorVersion() == 12)
        return "Monterey";
    // Compare against predefined constant to handle 10.16/11.0
    if (QOperatingSystemVersion::MacOSBigSur.version().isPrefixOf(version.version()))
        return "Big Sur";
    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";
        case 15:
            return "Catalina";
        }
    }
    // unknown, future version
#else
    Q_UNUSED(version);
#endif
    return nullptr;
}
 
#elif defined(Q_OS_WIN) || defined(Q_OS_CYGWIN)
 
#  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)
{
    return QWinRegistryKey(HKEY_LOCAL_MACHINE, LR"(SOFTWARE\Microsoft\Windows NT\CurrentVersion)")
            .stringValue(subKey);
}
 
static inline QString windowsDisplayVersion()
{
    // https://tickets.puppetlabs.com/browse/FACT-3058
    // The "ReleaseId" key stopped updating since Windows 10 20H2.
    if (QOperatingSystemVersion::current() >= QOperatingSystemVersion::Windows10_20H2)
        return readVersionRegistryString(L"DisplayVersion");
    else
        return readVersionRegistryString(L"ReleaseId");
}
 
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 += u'.' + 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(10, 0):
        if (workstation) {
            if (osver.dwBuildNumber >= 22000)
                return "11";
            return "10";
        }
        // else: Server
        if (osver.dwBuildNumber >= 20348)
            return "Server 2022";
        if (osver.dwBuildNumber >= 17763)
            return "Server 2019";
        return "Server 2016";
    }
#undef Q_WINVER
    // unknown, future version
    return nullptr;
}
 
#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(QByteArrayView str)
{
    // 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 (str.size() >= 2 && str.front() == '"' && str.back() == '"')
        str = str.sliced(1).chopped(1);
    return QString::fromUtf8(str);
}
 
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.size();
            v.productType = unquote({ptr, eol});
            continue;
        }
 
        if (line.startsWith(prettyNameKey)) {
            ptr += prettyNameKey.size();
            v.prettyName = unquote({ptr, eol});
            continue;
        }
 
        if (line.startsWith(versionKey)) {
            ptr += versionKey.size();
            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.size()) {
                // 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();
    return QByteArray(ptr, buffer.indexOf("\n")).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 ";
    const qsizetype releaseIndex = line.indexOf(keyword);
    v.productType = QString::fromLatin1(line.mid(0, releaseIndex)).remove(u' ');
    const qsizetype 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
 
#ifdef Q_OS_ANDROID
static const char *osVer_helper(QOperatingSystemVersion)
{
    // https://source.android.com/source/build-numbers.html
    // https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels
    const int sdk_int = QtAndroidPrivate::androidSdkVersion();
    switch (sdk_int) {
    case 3:
        return "Cupcake";
    case 4:
        return "Donut";
    case 5:
    case 6:
    case 7:
        return "Eclair";
    case 8:
        return "Froyo";
    case 9:
    case 10:
        return "Gingerbread";
    case 11:
    case 12:
    case 13:
        return "Honeycomb";
    case 14:
    case 15:
        return "Ice Cream Sandwich";
    case 16:
    case 17:
    case 18:
        return "Jelly Bean";
    case 19:
    case 20:
        return "KitKat";
    case 21:
    case 22:
        return "Lollipop";
    case 23:
        return "Marshmallow";
    case 24:
    case 25:
        return "Nougat";
    case 26:
    case 27:
        return "Oreo";
    case 28:
        return "Pie";
    case 29:
        return "10";
    case 30:
        return "11";
    case 31:
        return "12";
    case 32:
        return "12L";
    case 33:
        return "13";
    default:
        break;
    }
 
    return "";
}
#endif
 
QString QSysInfo::buildCpuArchitecture()
{
    return QStringLiteral(ARCH_PROCESSOR);
}
 
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 "power"_L1 + QLatin1StringView(u.machine + 3);
        if (strncmp(u.machine, "powerpc", 7) == 0)
            return "power"_L1 + QLatin1StringView(u.machine + 7);
        if (strcmp(u.machine, "Power Macintosh") == 0)
            return "power"_L1;
#  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();
}
 
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");
}
 
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();
}
 
QString QSysInfo::kernelVersion()
{
#ifdef Q_OS_WIN
    const auto osver = QOperatingSystemVersion::current();
    return QString::asprintf("%d.%d.%d",
                             osver.majorVersion(), osver.minorVersion(), osver.microVersion());
#else
    struct utsname u;
    if (uname(&u) == 0)
        return QString::fromLatin1(u.release);
    return QString();
#endif
}
 
 
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_VISIONOS)
    return QStringLiteral("visionos");
#elif defined(Q_OS_MACOS)
    return QStringLiteral("macos");
#elif defined(Q_OS_DARWIN)
    return QStringLiteral("darwin");
#elif defined(Q_OS_WASM)
    return QStringLiteral("wasm");
 
#elif defined(USE_ETC_OS_RELEASE) // Q_OS_UNIX
    QUnixOSVersion unixOsVersion;
    findUnixOsVersion(unixOsVersion);
    if (!unixOsVersion.productType.isEmpty())
        return unixOsVersion.productType;
#endif
    return unknownText();
}
 
QString QSysInfo::productVersion()
{
#if defined(Q_OS_ANDROID) || defined(Q_OS_DARWIN)
    const auto version = QOperatingSystemVersion::current();
    return QString::asprintf("%d.%d", version.majorVersion(), 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();
}
 
QString QSysInfo::prettyProductName()
{
#if defined(Q_OS_ANDROID) || defined(Q_OS_DARWIN) || defined(Q_OS_WIN)
    const auto version = QOperatingSystemVersion::current();
    const int majorVersion = version.majorVersion();
    const QString versionString = QString::asprintf("%d.%d", majorVersion, version.minorVersion());
    QString result = version.name() + u' ';
    const char *name = osVer_helper(version);
    if (!name)
        return result + versionString;
    result += QLatin1StringView(name);
#  if !defined(Q_OS_WIN)
    return result + " ("_L1 + versionString + u')';
#  else
    // (resembling winver.exe): Windows 10 "Windows 10 Version 1809"
    const auto displayVersion = windowsDisplayVersion();
    if (!displayVersion.isEmpty())
        result += " Version "_L1 + displayVersion;
    return result;
#  endif // Windows
#elif defined(Q_OS_HAIKU)
    return "Haiku "_L1 + 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) + u' ' + QString::fromLatin1(u.release);
#endif
    return unknownText();
}
 
#ifndef QT_BOOTSTRAPPED
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();
    QString hostName;
    hostName.resize(512);
    unsigned long len = hostName.size();
    BOOL res = GetComputerNameEx(ComputerNameDnsHostname,
            reinterpret_cast<wchar_t *>(const_cast<quint16 *>(hostName.utf16())), &len);
    if (!res && len > 512) {
        hostName.resize(len - 1);
        GetComputerNameEx(ComputerNameDnsHostname,
                reinterpret_cast<wchar_t *>(const_cast<quint16 *>(hostName.utf16())), &len);
    }
    hostName.truncate(len);
    return hostName;
#  else // !Q_OS_WIN
 
    char hostName[512];
    if (gethostname(hostName, sizeof(hostName)) == -1)
        return QString();
    hostName[sizeof(hostName) - 1] = '\0';
    return QString::fromLocal8Bit(hostName);
#  endif
#endif
}
#endif // QT_BOOTSTRAPPED
 
enum {
    UuidStringLen = sizeof("00000000-0000-0000-0000-000000000000") - 1
};
 
QByteArray QSysInfo::machineUniqueId()
{
#if defined(Q_OS_DARWIN) && __has_include(<IOKit/IOKitLib.h>)
    char uuid[UuidStringLen + 1];
    io_service_t service = IOServiceGetMatchingService(kIOMainPortDefault, 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
    const QString machineGuid = QWinRegistryKey(HKEY_LOCAL_MACHINE, LR"(SOFTWARE\Microsoft\Cryptography)")
                                .stringValue(u"MachineGuid"_s);
    if (!machineGuid.isEmpty())
        return machineGuid.toLatin1();
#endif
    return QByteArray();
}
 
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();
};
 
QT_END_NAMESPACE