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-rw-r--r--src/corelib/global/qglobal.cpp130
-rw-r--r--src/corelib/global/qsysinfo.h2
2 files changed, 130 insertions, 2 deletions
diff --git a/src/corelib/global/qglobal.cpp b/src/corelib/global/qglobal.cpp
index 6ab45e1487..619436e3db 100644
--- a/src/corelib/global/qglobal.cpp
+++ b/src/corelib/global/qglobal.cpp
@@ -1,7 +1,7 @@
/****************************************************************************
**
** Copyright (C) 2016 The Qt Company Ltd.
-** Copyright (C) 2016 Intel Corporation.
+** Copyright (C) 2017 Intel Corporation.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the QtCore module of the Qt Toolkit.
@@ -73,6 +73,10 @@
#include <Ws2tcpip.h>
#endif // Q_OS_WINRT
+#ifdef Q_OS_WIN
+# include <qt_windows.h>
+#endif
+
#if defined(Q_OS_VXWORKS) && defined(_WRS_KERNEL)
# include <envLib.h>
#endif
@@ -2818,10 +2822,11 @@ QString QSysInfo::prettyProductName()
This function returns the same as QHostInfo::localHostName().
- \sa QHostInfo::localDomainName
+ \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
@@ -2844,6 +2849,127 @@ QString QSysInfo::machineHostName()
}
#endif // QT_BOOTSTRAPPED
+enum {
+ UuidStringLen = sizeof("00000000-0000-0000-0000-000000000000") - 1
+};
+
+/*!
+ \since 5.10
+
+ 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()
+{
+ // the machine unique ID cannot change
+ static const QByteArray cache = []() {
+#ifdef Q_OS_BSD4
+ char uuid[UuidStringLen];
+ size_t uuidlen = sizeof(uuid);
+# ifdef KERN_HOSTUUID
+ 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);
+
+# else
+ // Darwin: no fixed value, we need to search by name
+ if (sysctlbyname("kern.uuid", uuid, &uuidlen, nullptr, 0) == 0 && uuidlen == sizeof(uuid))
+ return QByteArray(uuid, uuidlen);
+# endif
+#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) && !defined(Q_OS_WINRT)
+ // Let's poke at the registry
+ HKEY key = NULL;
+ if (RegOpenKeyEx(HKEY_LOCAL_MACHINE, L"SOFTWARE\\Microsoft\\Cryptography", 0, KEY_READ, &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();
+ }();
+ return cache;
+}
+
+/*!
+ \since 5.10
+
+ 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()
+{
+ // the boot unique ID cannot change
+ static const QByteArray cache = []() {
+#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];
+ size_t uuidlen = sizeof(uuid);
+ if (sysctlbyname("kern.bootsessionuuid", uuid, &uuidlen, nullptr, 0) == 0
+ && uuidlen == sizeof(uuid))
+ return QByteArray(uuid, uuidlen);
+#endif
+ return QByteArray();
+ }();
+ return cache;
+};
+
/*!
\macro void Q_ASSERT(bool test)
\relates <QtGlobal>
diff --git a/src/corelib/global/qsysinfo.h b/src/corelib/global/qsysinfo.h
index 6b73a17dc5..a3fa0fcb27 100644
--- a/src/corelib/global/qsysinfo.h
+++ b/src/corelib/global/qsysinfo.h
@@ -240,6 +240,8 @@ QT_WARNING_POP
static QString prettyProductName();
static QString machineHostName();
+ static QByteArray machineUniqueId();
+ static QByteArray bootUniqueId();
};
#undef QT_SYSINFO_DEPRECATED_X