Long live QOperatingSystemVersion!

This class provides a "type safe" way to compare and access operating
system version numbers.

[ChangeLog][Deprecation Notice] QSysInfo::windowsVersion() and
QSysInfo::macVersion() are deprecated and are replaced by the newly
introduced QOperatingSystemVersion.

Change-Id: I52b532de2e068ccf90faaa8342eee90c0a4145de
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

1 files changed, 171 insertions, 0 deletions

diff --git a/src/corelib/global/qoperatingsystemversion_win.cpp b/src/corelib/global/qoperatingsystemversion_win.cpp
new file mode 100644
index 0000000000..060ca2f7da
--- /dev/null
+++ b/src/corelib/global/qoperatingsystemversion_win.cpp
@@ -0,0 +1,171 @@
+/****************************************************************************
+**
+** Copyright (C) 2016 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtCore module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** 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.
+**
+** GNU General Public License Usage
+** 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
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qoperatingsystemversion_p.h"
+#include <qt_windows.h>
+#include <qbytearray.h>
+
+QT_BEGIN_NAMESPACE
+
+#ifdef Q_OS_WINRT
+static inline HMODULE moduleHandleForFunction(LPCVOID address)
+{
+    // This is a widely used, decades-old technique for retrieving the handle
+    // of a module and is effectively equivalent to GetModuleHandleEx
+    // (which is unavailable on WinRT)
+    MEMORY_BASIC_INFORMATION mbi = { 0, 0, 0, 0, 0, 0, 0 };
+    if (VirtualQuery(address, &mbi, sizeof(mbi)) == 0)
+        return 0;
+    return reinterpret_cast<HMODULE>(mbi.AllocationBase);
+}
+#endif
+
+static inline OSVERSIONINFOEX determineWinOsVersion()
+{
+    OSVERSIONINFOEX result = { sizeof(OSVERSIONINFOEX), 0, 0, 0, 0, {'\0'}, 0, 0, 0, 0, 0};
+
+#define GetProcAddressA GetProcAddress
+
+    // GetModuleHandle is not supported in WinRT and linking to it at load time
+    // will not pass the Windows App Certification Kit... but it exists and is functional,
+    // so use some unusual but widely used techniques to get a pointer to it
+#ifdef Q_OS_WINRT
+    // 1. Get HMODULE of kernel32.dll, using the address of some function exported by that DLL
+    HMODULE kernelModule = moduleHandleForFunction(reinterpret_cast<LPCVOID>(VirtualQuery));
+    if (Q_UNLIKELY(!kernelModule))
+        return result;
+
+    // 2. Get pointer to GetModuleHandle so we can then load other arbitrary modules (DLLs)
+    typedef HMODULE(WINAPI *GetModuleHandleFunction)(LPCWSTR);
+    GetModuleHandleFunction pGetModuleHandle = reinterpret_cast<GetModuleHandleFunction>(
+        GetProcAddressA(kernelModule, "GetModuleHandleW"));
+    if (Q_UNLIKELY(!pGetModuleHandle))
+        return result;
+#else
+#define pGetModuleHandle GetModuleHandleW
+#endif
+
+#ifndef Q_OS_WINCE
+    HMODULE ntdll = pGetModuleHandle(L"ntdll.dll");
+    if (Q_UNLIKELY(!ntdll))
+        return result;
+
+    // NTSTATUS is not defined on WinRT
+    typedef LONG NTSTATUS;
+    typedef NTSTATUS (NTAPI *RtlGetVersionFunction)(LPOSVERSIONINFO);
+
+    // RtlGetVersion is documented public API but we must load it dynamically
+    // because linking to it at load time will not pass the Windows App Certification Kit
+    // https://msdn.microsoft.com/en-us/library/windows/hardware/ff561910.aspx
+    RtlGetVersionFunction pRtlGetVersion = reinterpret_cast<RtlGetVersionFunction>(
+        GetProcAddressA(ntdll, "RtlGetVersion"));
+    if (Q_UNLIKELY(!pRtlGetVersion))
+        return result;
+
+    // GetVersionEx() has been deprecated in Windows 8.1 and will return
+    // only Windows 8 from that version on, so use the kernel API function.
+    pRtlGetVersion((LPOSVERSIONINFO) &result); // always returns STATUS_SUCCESS
+#else // !Q_OS_WINCE
+    GetVersionEx(&result);
+#endif
+    return result;
+}
+
+OSVERSIONINFOEX qWindowsVersionInfo()
+{
+    OSVERSIONINFOEX realResult = determineWinOsVersion();
+#ifdef QT_DEBUG
+    {
+        if (Q_UNLIKELY(qEnvironmentVariableIsSet("QT_WINVER_OVERRIDE"))) {
+            OSVERSIONINFOEX result = realResult;
+            result.dwMajorVersion = 0;
+            result.dwMinorVersion = 0;
+
+            // Erase any build number and service pack information
+            result.dwBuildNumber = 0;
+            result.szCSDVersion[0] = L'\0';
+            result.wServicePackMajor = 0;
+            result.wServicePackMinor = 0;
+
+            const QByteArray winVerOverride = qgetenv("QT_WINVER_OVERRIDE");
+            if (winVerOverride == "WINDOWS7" || winVerOverride == "2008_R2") {
+                result.dwMajorVersion = 6;
+                result.dwMinorVersion = 1;
+            } else if (winVerOverride == "WINDOWS8" || winVerOverride == "2012") {
+                result.dwMajorVersion = 6;
+                result.dwMinorVersion = 2;
+            } else if (winVerOverride == "WINDOWS8_1" || winVerOverride == "2012_R2") {
+                result.dwMajorVersion = 6;
+                result.dwMinorVersion = 3;
+            } else if (winVerOverride == "WINDOWS10" || winVerOverride == "2016") {
+                result.dwMajorVersion = 10;
+            } else {
+                return realResult;
+            }
+
+            if (winVerOverride == "2008_R2"
+                || winVerOverride == "2012"
+                || winVerOverride == "2012_R2"
+                || winVerOverride == "2016") {
+                // If the current host OS is a domain controller and the override OS
+                // is also a server type OS, preserve that information
+                if (result.wProductType == VER_NT_WORKSTATION)
+                    result.wProductType = VER_NT_SERVER;
+            } else {
+                // Any other OS must be a workstation OS type
+                result.wProductType = VER_NT_WORKSTATION;
+            }
+        }
+    }
+#endif
+    return realResult;
+}
+
+QOperatingSystemVersion QOperatingSystemVersion::current()
+{
+    QOperatingSystemVersion v;
+    v.m_os = currentType();
+    const OSVERSIONINFOEX osv = qWindowsVersionInfo();
+    v.m_major = osv.dwMajorVersion;
+    v.m_minor = osv.dwMinorVersion;
+    v.m_micro = osv.dwBuildNumber;
+    return v;
+}
+
+QT_END_NAMESPACE