wintun: merge opening device registry key

This also introduces waiting for key to appear on initial access.

See if this resolves the issue caused by HDD power-up delay resulting in
failure to create the adapter.

Signed-off-by: Simon Rozman <simon@rozman.si>

diff --git a/tun/wintun/wintun_windows.go b/tun/wintun/wintun_windows.go
index 755026309f105ff9451760c301d0d4dc450e8d03..55d4ed08bc4eaafb11c7d9af0769ffbc8637ee32 100644 (file)
--- a/tun/wintun/wintun_windows.go
+++ b/tun/wintun/wintun_windows.go
@@ -262,14 +262,23 @@ func CreateInterface(description string, requestedGUID *windows.GUID) (wintun *W
        devInfoList.CallClassInstaller(setupapi.DIF_REGISTER_COINSTALLERS, deviceData)
 
        var key registry.Key
-       if requestedGUID != nil {
-               key, err = devInfoList.OpenDevRegKey(deviceData, setupapi.DICS_FLAG_GLOBAL, 0, setupapi.DIREG_DRV, registry.SET_VALUE)
-               if err != nil {
-                       err = fmt.Errorf("OpenDevRegKey failed: %v", err)
-                       return
+       const pollTimeout = time.Millisecond * 50
+       for i := 0; i < int(waitForRegistryTimeout/pollTimeout); i++ {
+               if i != 0 {
+                       time.Sleep(pollTimeout)
+               }
+               key, err = devInfoList.OpenDevRegKey(deviceData, setupapi.DICS_FLAG_GLOBAL, 0, setupapi.DIREG_DRV, registry.SET_VALUE|registry.QUERY_VALUE|registry.NOTIFY)
+               if err == nil {
+                       break
                }
+       }
+       if err != nil {
+               err = fmt.Errorf("SetupDiOpenDevRegKey failed: %v", err)
+               return
+       }
+       defer key.Close()
+       if requestedGUID != nil {
                err = key.SetStringValue("NetSetupAnticipatedInstanceId", requestedGUID.String())
-               key.Close()
                if err != nil {
                        err = fmt.Errorf("SetStringValue(NetSetupAnticipatedInstanceId) failed: %v", err)
                        return
@@ -309,21 +318,6 @@ func CreateInterface(description string, requestedGUID *windows.GUID) (wintun *W
        // DIF_INSTALLDEVICE returns almost immediately, while the device installation
        // continues in the background. It might take a while, before all registry
        // keys and values are populated.
-       const pollTimeout = time.Millisecond * 50
-       for i := 0; i < int(waitForRegistryTimeout/pollTimeout); i++ {
-               if i != 0 {
-                       time.Sleep(pollTimeout)
-               }
-               key, err = devInfoList.OpenDevRegKey(deviceData, setupapi.DICS_FLAG_GLOBAL, 0, setupapi.DIREG_DRV, registry.QUERY_VALUE|registry.NOTIFY)
-               if err == nil {
-                       break
-               }
-       }
-       if err != nil {
-               err = fmt.Errorf("SetupDiOpenDevRegKey failed: %v", err)
-               return
-       }
-       defer key.Close()
        _, err = registryEx.GetStringValueWait(key, "NetCfgInstanceId", waitForRegistryTimeout)
        if err != nil {
                err = fmt.Errorf("GetStringValueWait(NetCfgInstanceId) failed: %v", err)