97 }

    98 

    99 /*!

   100     Returns the path part of a registry key.

   101     Ei.

   102         For a key

   103             "Software\\Microsoft\\VisualStudio\\8.0\\Setup\\VC\\ProductDir"

   104         it returns

   105             "Software\\Microsoft\\VisualStudio\\8.0\\Setup\\VC\\"

   106 */

   107 QString Environment::keyPath(const QString &rKey)

   108 {

   109     int idx = rKey.lastIndexOf(QLatin1Char('\\'));

   110     if (idx == -1)

   111         return QString();

   112     return rKey.left(idx + 1);

   113 }

   114 

   115 /*!

   116     Returns the name part of a registry key.

   117     Ei.

   118         For a key

   119             "Software\\Microsoft\\VisualStudio\\8.0\\Setup\\VC\\ProductDir"

   120         it returns

   121             "ProductDir"

   122 */

   123 QString Environment::keyName(const QString &rKey)

   124 {

   125     int idx = rKey.lastIndexOf(QLatin1Char('\\'));

   126     if (idx == -1)

   127         return rKey;

   128 

   129     QString res(rKey.mid(idx + 1));

   130     if (res == "Default" || res == ".")

   131         res = "";

   132     return res;

   133 }

   134 

   135 /*!

   136     Returns a registry keys value in string form.

   137     If the registry key does not exist, or cannot be accessed, a

   138     QString() is returned.

   139 */

   140 QString Environment::readRegistryKey(HKEY parentHandle, const QString &rSubkey)

   141 {

   142 #ifndef Q_OS_WIN32

   143     return QString();

   144 #else

   145     QString rSubkeyName = keyName(rSubkey);

   146     QString rSubkeyPath = keyPath(rSubkey);

   147 

   148     HKEY handle = 0;

   149     LONG res = RegOpenKeyEx(parentHandle, (wchar_t*)rSubkeyPath.utf16(), 0, KEY_READ, &handle);

   150     if (res != ERROR_SUCCESS)

   151         return QString();

   152 

   153     // get the size and type of the value

   154     DWORD dataType;

   155     DWORD dataSize;

   156     res = RegQueryValueEx(handle, (wchar_t*)rSubkeyName.utf16(), 0, &dataType, 0, &dataSize);

   157     if (res != ERROR_SUCCESS) {

   158         RegCloseKey(handle);

   159         return QString();

   160     }

   161 

   162     // get the value

   163     QByteArray data(dataSize, 0);

   164     res = RegQueryValueEx(handle, (wchar_t*)rSubkeyName.utf16(), 0, 0,

   165                            reinterpret_cast<unsigned char*>(data.data()), &dataSize);

   166     if (res != ERROR_SUCCESS) {

   167         RegCloseKey(handle);

   168         return QString();

   169     }

   170 

   171     QString result;

   172     switch (dataType) {

   173         case REG_EXPAND_SZ:

   174         case REG_SZ: {

   175             result = QString::fromWCharArray(((const wchar_t *)data.constData()));

   176             break;

   177         }

   178 

   179         case REG_MULTI_SZ: {

   180             QStringList l;

   181             int i = 0;

   182             for (;;) {

   183                 QString s = QString::fromWCharArray((const wchar_t *)data.constData() + i);

   184                 i += s.length() + 1;

   185 

   186                 if (s.isEmpty())

   187                     break;

   188                 l.append(s);

   189             }

   190             result = l.join(", ");

   191             break;

   192         }

   193 

   194         case REG_NONE:

   195         case REG_BINARY: {

   196             result = QString::fromWCharArray((const wchar_t *)data.constData(), data.size() / 2);

   197             break;

   198         }

   199 

   200         case REG_DWORD_BIG_ENDIAN:

   201         case REG_DWORD: {

   202             Q_ASSERT(data.size() == sizeof(int));

   203             int i;

   204             memcpy((char*)&i, data.constData(), sizeof(int));

   205             result = QString::number(i);

   206             break;

   207         }

   208 

   209         default:

   210             qWarning("QSettings: unknown data %d type in windows registry", dataType);

   211             break;

   212     }

   213 

   214     RegCloseKey(handle);

   215     return result;

   216 #endif