1 files changed, 133 insertions, 0 deletions
diff --git a/src/linguist/shared/registry.cpp b/src/linguist/shared/registry.cpp
new file mode 100644
index 000000000..7ab0c71fe
--- /dev/null
+++ b/src/linguist/shared/registry.cpp
@@ -0,0 +1,133 @@
+// Copyright (C) 2016 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only WITH Qt-GPL-exception-1.0
+
+#include <QtCore/qstringlist.h>
+#include "registry_p.h"
+
+QT_BEGIN_NAMESPACE
+
+#ifdef Q_OS_WIN32
+/*
+  Returns the path part of a registry key.
+  e.g.
+      For a key
+          "Software\\Microsoft\\VisualStudio\\8.0\\Setup\\VC\\ProductDir"
+      it returns
+          "Software\\Microsoft\\VisualStudio\\8.0\\Setup\\VC\\"
+*/
+static QString keyPath(const QString &rKey)
+{
+    int idx = rKey.lastIndexOf(QLatin1Char('\\'));
+    if (idx == -1)
+        return QString();
+    return rKey.left(idx + 1);
+}
+
+/*
+  Returns the name part of a registry key.
+  e.g.
+      For a key
+          "Software\\Microsoft\\VisualStudio\\8.0\\Setup\\VC\\ProductDir"
+      it returns
+          "ProductDir"
+*/
+static QString keyName(const QString &rKey)
+{
+    int idx = rKey.lastIndexOf(QLatin1Char('\\'));
+    if (idx == -1)
+        return rKey;
+
+    QString res(rKey.mid(idx + 1));
+    if (res == QLatin1String("Default") || res == QLatin1String("."))
+        res = QString();
+    return res;
+}
+#endif
+
+QString qt_readRegistryKey(HKEY parentHandle, const QString &rSubkey, unsigned long options)
+{
+    QString result;
+
+#ifdef Q_OS_WIN32
+    QString rSubkeyName = keyName(rSubkey);
+    QString rSubkeyPath = keyPath(rSubkey);
+
+    HKEY handle = nullptr;
+    LONG res = RegOpenKeyEx(parentHandle, (wchar_t*)rSubkeyPath.utf16(), 0,
+                            KEY_READ | options, &handle);
+
+    if (res != ERROR_SUCCESS)
+        return QString();
+
+    // get the size and type of the value
+    DWORD dataType;
+    DWORD dataSize;
+    res = RegQueryValueEx(handle, (wchar_t*)rSubkeyName.utf16(), nullptr, &dataType, nullptr, &dataSize);
+    if (res != ERROR_SUCCESS) {
+        RegCloseKey(handle);
+        return QString();
+    }
+
+    // get the value
+    QByteArray data(dataSize, 0);
+    res = RegQueryValueEx(handle, (wchar_t*)rSubkeyName.utf16(), nullptr, nullptr,
+                          reinterpret_cast<unsigned char*>(data.data()), &dataSize);
+    if (res != ERROR_SUCCESS) {
+        RegCloseKey(handle);
+        return QString();
+    }
+
+    switch (dataType) {
+        case REG_EXPAND_SZ:
+        case REG_SZ: {
+            result = QString::fromWCharArray(((const wchar_t *)data.constData()));
+            break;
+        }
+
+        case REG_MULTI_SZ: {
+            QStringList l;
+            int i = 0;
+            for (;;) {
+                QString s = QString::fromWCharArray((const wchar_t *)data.constData() + i);
+                i += s.length() + 1;
+
+                if (s.isEmpty())
+                    break;
+                l.append(s);
+            }
+            result = l.join(QLatin1String(", "));
+            break;
+        }
+
+        case REG_NONE:
+        case REG_BINARY: {
+            result = QString::fromWCharArray((const wchar_t *)data.constData(), data.size() / 2);
+            break;
+        }
+
+        case REG_DWORD_BIG_ENDIAN:
+        case REG_DWORD: {
+            Q_ASSERT(data.size() == sizeof(int));
+            int i;
+            memcpy((char*)&i, data.constData(), sizeof(int));
+            result = QString::number(i);
+            break;
+        }
+
+        default:
+            qWarning("QSettings: unknown data %u type in windows registry", quint32(dataType));
+            break;
+    }
+
+    RegCloseKey(handle);
+#else
+    Q_UNUSED(parentHandle);
+    Q_UNUSED(rSubkey);
+    Q_UNUSED(options);
+#endif
+
+    return result;
+}
+
+QT_END_NAMESPACE
+