seb-win-refactoring/SafeExamBrowser.WindowsApi/DesktopFactory.cs

85 lines
2.3 KiB
C#

/*
* Copyright (c) 2023 ETH Zürich, Educational Development and Technology (LET)
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*/
using System;
using System.ComponentModel;
using System.Runtime.InteropServices;
using SafeExamBrowser.Logging.Contracts;
using SafeExamBrowser.WindowsApi.Contracts;
using SafeExamBrowser.WindowsApi.Constants;
namespace SafeExamBrowser.WindowsApi
{
public class DesktopFactory : IDesktopFactory
{
private ILogger logger;
public DesktopFactory(ILogger logger)
{
this.logger = logger;
}
public IDesktop CreateNew(string name)
{
logger.Debug($"Attempting to create new desktop '{name}'...");
var handle = User32.CreateDesktop(name, IntPtr.Zero, IntPtr.Zero, 0, (uint) AccessMask.GENERIC_ALL, IntPtr.Zero);
if (handle == IntPtr.Zero)
{
logger.Error($"Failed to create new desktop '{name}'!");
throw new Win32Exception(Marshal.GetLastWin32Error());
}
var desktop = new Desktop(handle, name);
logger.Debug($"Successfully created desktop {desktop}.");
return desktop;
}
public IDesktop GetCurrent()
{
var threadId = Kernel32.GetCurrentThreadId();
var handle = User32.GetThreadDesktop(threadId);
var name = String.Empty;
var nameLength = 0;
if (handle == IntPtr.Zero)
{
logger.Error($"Failed to get desktop handle for thread with ID = {threadId}!");
throw new Win32Exception(Marshal.GetLastWin32Error());
}
logger.Debug($"Found desktop handle for thread with ID = {threadId}. Attempting to get desktop name...");
User32.GetUserObjectInformation(handle, Constant.UOI_NAME, IntPtr.Zero, 0, ref nameLength);
var namePointer = Marshal.AllocHGlobal(nameLength);
var success = User32.GetUserObjectInformation(handle, Constant.UOI_NAME, namePointer, nameLength, ref nameLength);
if (!success)
{
logger.Error($"Failed to retrieve name for desktop with handle = {handle}!");
throw new Win32Exception(Marshal.GetLastWin32Error());
}
name = Marshal.PtrToStringAnsi(namePointer);
Marshal.FreeHGlobal(namePointer);
var desktop = new Desktop(handle, name);
logger.Debug($"Successfully determined current desktop {desktop}.");
return desktop;
}
}
}