// NOTE: this function throws a COMException if the object was not found
public static object?GetActiveObject(string progId)
{
if (progId is null)
{
throw new ArgumentNullException(nameof(progId));
}
// get the CLSID for the supplied ProgId
var getClsidResult = ExtendedPInvoke.CLSIDFromProgIDEx(progId, out var clsid);
if (getClsidResult != (uint)ExtendedPInvoke.S_OK)
{
switch (getClsidResult)
{
case (uint)ExtendedPInvoke.Win32ErrorCode.CO_E_CLASSSTRING:
throw new COMException("Invalid class string");
case (uint)ExtendedPInvoke.Win32ErrorCode.REGDB_E_WRITEREGDB:
throw new COMException("Could not write key to registry");
}
}
var getActiveObjectResult = ExtendedPInvoke.GetActiveObject(ref clsid, IntPtr.Zero, out var activeObject);
if (getActiveObjectResult != (uint)ExtendedPInvoke.S_OK)
{
// if we could not get the object, return null
// NOTE: if we want to distinguish between error results (i.e. object not active vs. others), we could read the win32 "last error" code
return(null);
}
return(activeObject);
}
//
public static MorphicResult <string, GetPathToExecutableForFileError> GetAssociatedExecutableForFile(string path)
{
StringBuilder pathToExecutable = new StringBuilder(ExtendedPInvoke.MAX_PATH + 1);
var resultCode = ExtendedPInvoke.FindExecutable(path, null, pathToExecutable);
if (resultCode.ToInt64() > 32)
{
// success
return(MorphicResult.OkResult(pathToExecutable.ToString()));
}
else
{
// failure
switch (resultCode.ToInt64())
{
case (Int64)ExtendedPInvoke.ShellExecuteErrorCode.SE_ERR_FNF:
return(MorphicResult.ErrorResult(GetPathToExecutableForFileError.FileNotFound));
case (Int64)ExtendedPInvoke.ShellExecuteErrorCode.SE_ERR_PNF:
return(MorphicResult.ErrorResult(GetPathToExecutableForFileError.PathIsInvalid));
case (Int64)ExtendedPInvoke.ShellExecuteErrorCode.SE_ERR_ACCESSDENIED:
return(MorphicResult.ErrorResult(GetPathToExecutableForFileError.AccessDenied));
case (Int64)ExtendedPInvoke.ShellExecuteErrorCode.SE_ERR_OOM:
return(MorphicResult.ErrorResult(GetPathToExecutableForFileError.OutOfMemoryOrResources));
case (Int64)ExtendedPInvoke.ShellExecuteErrorCode.SE_ERR_NOASSOC:
return(MorphicResult.ErrorResult(GetPathToExecutableForFileError.NoAssociatedExecutable));
default:
return(MorphicResult.ErrorResult(GetPathToExecutableForFileError.UnknownShellExecuteErrorCode));
}
}
}
/* helper functions */
// some more details: https://blog.quarkslab.com/playing-with-the-windows-notification-facility-wnf.html
private static MorphicResult <byte[], MorphicUnit> QueryWnfStateData(ExtendedPInvoke.WNF_STATE_NAME stateName)
{
const uint MAX_BUFFER_LENGTH = 4096;
uint bufferSize = MAX_BUFFER_LENGTH;
var pointerToBuffer = Marshal.AllocHGlobal((int)bufferSize);
try
{
uint changeStamp;
var queryWnfStateDataResult = ExtendedPInvoke.NtQueryWnfStateData(ref stateName, IntPtr.Zero, IntPtr.Zero, out changeStamp, pointerToBuffer, ref bufferSize);
if (queryWnfStateDataResult != 0)
{
return(MorphicResult.ErrorResult());
}
var bufferSizeAsInt = (int)bufferSize;
var result = new byte[bufferSizeAsInt];
Marshal.Copy(pointerToBuffer, result, 0, bufferSizeAsInt);
return(MorphicResult.OkResult(result));
}
finally
{
Marshal.FreeHGlobal(pointerToBuffer);
}
}
protected virtual void Dispose(bool disposing)
{
if (!_isDisposed)
{
if (disposing)
{
// dispose any managed objects here
}
// free unmanaged resources
// NOTE: this function will return false if it fails
// NOTE: in theory the system should clean up after this hook handle automatically (so we could probably comment out the following two lines of code)
_ = ExtendedPInvoke.UnhookWindowsHookEx(_hookHandle.DangerousGetHandle());
_hookHandle.SetHandleAsInvalid();
// set any large fields to null
_isDisposed = true;
}
}
private static MorphicResult <MorphicUnit, MorphicUnit> UpdateWnfStateData(ExtendedPInvoke.WNF_STATE_NAME stateName, byte[] buffer)
{
var bufferLength = buffer.Length;
var pointerToBuffer = Marshal.AllocHGlobal(bufferLength);
try
{
Marshal.Copy(buffer, 0, pointerToBuffer, bufferLength);
var updateWnfStateDataResult = ExtendedPInvoke.NtUpdateWnfStateData(ref stateName, pointerToBuffer, (uint)bufferLength, IntPtr.Zero /* null */, IntPtr.Zero, 0, 0);
if (updateWnfStateDataResult != 0)
{
return(MorphicResult.ErrorResult());
}
}
finally
{
Marshal.FreeHGlobal(pointerToBuffer);
}
return(MorphicResult.OkResult());
}
