/// <summary>
/// The method calls RoOriginateLanguageException. The method has all the logic in try, catch block to ensure that none of the exception helpers
/// throw exception themselves.
/// </summary>
/// <param name="ex"></param>
/// <returns></returns>
private static bool OriginateLanguageException(Exception ex)
{
IntPtr pUnk = IntPtr.Zero;
HSTRING errorMsg = default(HSTRING);
try
{
pUnk = McgMarshal.ObjectToComInterface(ex, InternalTypes.IUnknown);
if (pUnk != IntPtr.Zero)
{
RuntimeAugments.GenerateExceptionInformationForDump(ex, pUnk);
errorMsg = McgMarshal.StringToHString(ex.Message);
return(ExternalInterop.RoOriginateLanguageException(ex.HResult, errorMsg, pUnk) >= 0);
}
}
catch (Exception)
{
// We can't do anything here and hence simply swallow the exception
}
finally
{
McgMarshal.ComSafeRelease(pUnk);
if (errorMsg.handle != IntPtr.Zero)
{
ExternalInterop.WindowsDeleteString(errorMsg.handle.ToPointer());
}
}
return(false);
}
#pragma warning restore 649, 169
/// <summary>
/// This method gets the mapping hr for the exception. and also does the right thing to propogate the hr correctly to the native layer.
///
/// We check if the exception is a pure managed exception or an exception created from an hr that entered the system from native.
/// a. If it is a pure managed exception we create an IUnknown ptr from the exception and RoOriginateLanguageException on it.
/// This helps us to preserve our managed exception and throw the same exception in case this exception roundtrips and hence preserve the call stack.
/// Since the API RoOriginateLanguageException is available only on windows blue, we can't do the same in win8. In desktop CLR we use the non-modern SDK API
/// GetErroInfo\SetErrorInfo combination to preserve managed exception but unfortunately we can't do this in .NET Native and hence we only our able to preserve the exception message and
/// type and end up getting a rough stacktrace PS - Even this behavior in win8 is possible only in debug mode as RoSetErrorReportingFlags is set to UseSetErrorInfo only in debug mode.
///
/// b. In case the exception is created due to an hr that entered managed world via native call, we will have restrictederrorInfo associated with it. In this case
/// we do not RoOriginateLanguageException\RoOriginateError and rather preserve the exception stack trace by simply calling the SetRestrictedErrorInfo.
///
/// c. PS - Due to the use of modern SDK we have no way to round trip exceptions in classicCOM scenarios any more.
/// This is because we can't use SetErrorInfo\GetErrorInfo APIs at all. Unfortunately we have no workaround for this even in windowsBlue!
/// With the use of IRestrictedErrorInfo has some disadvantages as we lose other info available with IErrorInfo in terms of HelpFile etc.
///
/// d. This class puts all the logic in try, catch block to ensure that none of the exception helpers.
/// throw exception themselves.
/// </summary>
/// <param name="ex"></param>
/// <param name="isWinRTScenario"></param>
/// <returns></returns>
internal static int GetHRForExceptionWithErrorPropogationNoThrow(Exception ex, bool isWinRTScenario)
{
int hr = ex.HResult;
if (hr == Interop.COM.COR_E_OBJECTDISPOSED && isWinRTScenario)
{
// Since ObjectDisposedException is projected to RO_E_CLOSED in WINRT we make sure to use the correct hr while updating the CRuntimeError object of Windows.
hr = Interop.COM.RO_E_CLOSED;
}
try
{
// Check whether the exception has an associated RestrictedErrorInfo associated with it.
if (isWinRTScenario)
{
IntPtr pRestrictedErrorInfo;
object restrictedErrorInfo;
if (InteropExtensions.TryGetRestrictedErrorObject(ex, out restrictedErrorInfo) && restrictedErrorInfo != null)
{
// We have the restricted errorInfo associated with this object and hence this exception was created by an hr entering managed through native.
pRestrictedErrorInfo = McgMarshal.ObjectToComInterface(restrictedErrorInfo, InternalTypes.IRestrictedErrorInfo);
if (pRestrictedErrorInfo != IntPtr.Zero)
{
// We simply call SetRestrictedErrorInfo since we do not want to originate the exception again.
ExternalInterop.SetRestrictedErrorInfo(pRestrictedErrorInfo);
McgMarshal.ComSafeRelease(pRestrictedErrorInfo);
}
}
else
{
// we are in windows blue and hence we can preserve our exception so that we can reuse this exception in case it comes back and provide richer exception support.
OriginateLanguageException(ex);
}
}
else
{
// We are either pre WinBlue or in classicCOM scenario and hence we can only RoOriginateError at this point.
// Desktop CLR uses SetErrorInfo and preserves the exception object which helps us give the same support as winBlue.
// Since .NET Native can only use modern SDK we have a compatibility break here by only preserving the restrictederrorMsg and exception type but the stack trace will be incorrect.
// Also RoOriginateError works only under the debugger since RoSetErrorReportingFlags is set to RO_ERROR_REPORTING_USESETERRORINFO.
// If we are not under the debugger we can't set this API since it is not part of the modernSDK and hence this will not work
// and will result in different behavior than the desktop.
HSTRING errorMsg = McgMarshal.StringToHString(ex.Message);
ExternalInterop.RoOriginateError(ex.HResult, errorMsg);
ExternalInterop.WindowsDeleteString(errorMsg.handle.ToPointer());
}
}
catch (Exception)
{
// We can't throw an exception here and hence simply swallow it.
}
return(hr);
}