[idd] helper: added new helper service

As the IDD itself runs in a WUMDF sandbox, it doesn't have enough
access to perform interactive operations such as moving the cursor.

This helper service communicates with the IDD over a named pipe,
so that we can perform these things, as well as in the future provide
a configuration GUI.

idd/LGIddHelper/CPipeClient.cpp

@@ -0,0 +1,231 @@
+/**
+ * Looking Glass
+ * Copyright <20> 2017-2025 The Looking Glass Authors
+ * https://looking-glass.io
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc., 59
+ * Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include "CPipeClient.h"
+#include "CDebug.h"
+
+#include <setupapi.h>
+#include <tchar.h>
+
+CPipeClient g_pipe;
+
+bool CPipeClient::Init()
+{
+  DeInit();
+  if (!IsLGIddDeviceAttached())
+  {
+    DEBUG_ERROR("Looking Glass Indirect Display Device not found");
+    return false;
+  }
+
+  m_running = true;
+  m_thread.Attach(CreateThread(
+    NULL,
+    0,
+    _pipeThread,
+    (LPVOID)this,
+    0,
+    NULL));
+
+  if (!m_thread.IsValid())
+  {
+    DEBUG_ERROR_HR(GetLastError(), "Failed to create the pipe thread");
+    return false;
+  }
+
+  return true;
+}
+
+void CPipeClient::DeInit()
+{
+  m_connected = false;
+  if (m_thread.IsValid())
+  {
+    m_running = false;
+    WaitForSingleObject(m_thread.Get(), INFINITE);
+    m_thread.Close();
+  }
+
+  if (m_pipe.IsValid())
+  {
+    FlushFileBuffers(m_pipe.Get());
+    m_pipe.Close();
+  }
+}
+
+bool CPipeClient::IsLGIddDeviceAttached()
+{
+  HDEVINFO hDevInfo = SetupDiGetClassDevs(
+    NULL,
+    NULL,
+    NULL,
+    DIGCF_ALLCLASSES | DIGCF_PRESENT
+  );
+
+  if (hDevInfo == INVALID_HANDLE_VALUE)
+    return false;
+
+  SP_DEVINFO_DATA DeviceInfoData;
+  DeviceInfoData.cbSize = sizeof(SP_DEVINFO_DATA);
+  bool found = false;
+
+  for (DWORD i = 0; SetupDiEnumDeviceInfo(hDevInfo, i, &DeviceInfoData); i++)
+  {
+    DWORD DataT;
+    TCHAR buffer[1024];
+    DWORD buffersize = 0;
+
+    if (!SetupDiGetDeviceRegistryProperty(
+      hDevInfo,
+      &DeviceInfoData,
+      SPDRP_HARDWAREID,
+      &DataT,
+      (PBYTE)buffer,
+      sizeof(buffer),
+      &buffersize))
+      continue;
+
+    for (LPCTSTR p = buffer; *p; p += _tcslen(p) + 1)
+      if (_tcsicmp(p, _T("Root\\LGIdd")) == 0)
+      {
+        found = true;
+        break;
+      }
+
+    if (found)
+      break;
+  }
+
+  SetupDiDestroyDeviceInfoList(hDevInfo);
+  return found;
+}
+
+/* APIs like SetCursorPos are applied to the desktop our thread is
+ * attached to. If the user switches to the secure desktop (UAC, etc)
+ * then these functions will not work, so call this first to ensure
+ * the call is effective */
+void CPipeClient::SetActiveDesktop()
+{
+  HDESK desktop = NULL;
+  desktop = OpenInputDesktop(0, FALSE, GENERIC_READ);
+  if (!desktop)
+    DEBUG_ERROR_HR(GetLastError(), "OpenInputDesktop Failed");
+  else
+  {
+    if (!SetThreadDesktop(desktop))
+      DEBUG_ERROR_HR(GetLastError(), "SetThreadDesktop Failed");
+    CloseDesktop(desktop);
+  }
+}
+
+void CPipeClient::WriteMsg(const LGPipeMsg& msg)
+{
+  DWORD written;
+  if (!WriteFile(m_pipe.Get(), &msg, sizeof(msg), &written, NULL))
+  {
+    DWORD err = GetLastError();
+    if (err == ERROR_BROKEN_PIPE)
+    {
+      DEBUG_WARN_HR(err, "Client disconnected, failed to write");
+      m_connected = false;
+      return;
+    }
+
+    DEBUG_WARN_HR(err, "WriteFile failed on the pipe");
+    return;
+  }
+
+  FlushFileBuffers(m_pipe.Get());
+}
+
+void CPipeClient::Thread()
+{
+  DEBUG_INFO("Pipe thread started");
+  while (m_running)
+  {
+    if (!WaitNamedPipeA(LG_PIPE_NAME, 5000))
+    {
+      if (!IsLGIddDeviceAttached())
+      {
+        m_running = false;
+        DEBUG_ERROR("Device is no longer available, shutting down");
+        break;
+      }
+      continue;
+    }
+
+    m_pipe.Attach(CreateFileA(
+      LG_PIPE_NAME,
+      GENERIC_READ | GENERIC_WRITE,
+      0,
+      NULL,
+      OPEN_EXISTING,
+      0,
+      NULL
+    ));
+
+    if (!m_pipe.IsValid())
+    {
+      DEBUG_ERROR_HR(GetLastError(), "Failed to open the named pipe");
+      continue;
+    }
+
+    m_connected = true;
+    DEBUG_INFO("Pipe connected");
+    while (m_running && m_connected)
+    {
+      LGPipeMsg msg;
+      DWORD bytesRead;
+      if (!ReadFile(m_pipe.Get(), &msg, sizeof(msg), &bytesRead, NULL))
+      {
+        DEBUG_ERROR_HR(GetLastError(), "ReadFile Failed");
+        break;
+      }
+
+      if (bytesRead != sizeof(msg) || msg.size != sizeof(msg))
+      {
+        DEBUG_ERROR("Corrupted data");
+        break;
+      }
+
+      switch (msg.type)
+      {
+        case LGPipeMsg::SETCURSORPOS:
+          HandleSetCursorPos(msg);
+          break;
+
+        default:
+          DEBUG_ERROR("Unknown message type %d", msg.type);
+          break;
+      }
+    }
+
+    m_pipe.Close();
+    m_connected = false;
+    DEBUG_INFO("Pipe closed");
+  }
+  DEBUG_INFO("Pipe thread shutdown");
+}
+
+void CPipeClient::HandleSetCursorPos(const LGPipeMsg& msg)
+{
+  SetActiveDesktop();
+  SetCursorPos(msg.curorPos.x, msg.curorPos.y);
+}

idd/LGIddHelper/CPipeClient.h

@@ -0,0 +1,60 @@
+/**
+ * Looking Glass
+ * Copyright <20> 2017-2025 The Looking Glass Authors
+ * https://looking-glass.io
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc., 59
+ * Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#pragma once
+
+#include <windows.h>
+#include <stdint.h>
+#include <wrl.h>
+
+#include "PipeMsg.h"
+
+using namespace Microsoft::WRL;
+using namespace Microsoft::WRL::Wrappers;
+using namespace Microsoft::WRL::Wrappers::HandleTraits;
+
+class CPipeClient
+{
+private:
+  HandleT<HANDLENullTraits> m_pipe;
+  HandleT<HANDLENullTraits> m_thread;
+  bool m_running = false;
+  bool m_connected = false;
+
+  static DWORD WINAPI _pipeThread(LPVOID lpParam) { ((CPipeClient*)lpParam)->Thread(); return 0; }
+  void Thread();
+
+  void WriteMsg(const LGPipeMsg& msg);
+
+  void SetActiveDesktop();
+  
+  void HandleSetCursorPos(const LGPipeMsg& msg);
+
+public:
+  ~CPipeClient() { DeInit(); }
+
+  static bool IsLGIddDeviceAttached();
+
+  bool Init();
+  void DeInit();
+  bool IsRunning() { return m_running; }
+};
+
+extern CPipeClient g_pipe;

idd/LGIddHelper/LGIddHelper.vcxproj

@@ -0,0 +1,188 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <Import Project="..\packages\MSBuilder.Git.0.3.0\build\MSBuilder.Git.props" Condition="Exists('..\packages\MSBuilder.Git.0.3.0\build\MSBuilder.Git.props')" />
+  <ItemGroup Label="ProjectConfigurations">
+    <ProjectConfiguration Include="Debug|Win32">
+      <Configuration>Debug</Configuration>
+      <Platform>Win32</Platform>
+    </ProjectConfiguration>
+    <ProjectConfiguration Include="Release|Win32">
+      <Configuration>Release</Configuration>
+      <Platform>Win32</Platform>
+    </ProjectConfiguration>
+    <ProjectConfiguration Include="Debug|x64">
+      <Configuration>Debug</Configuration>
+      <Platform>x64</Platform>
+    </ProjectConfiguration>
+    <ProjectConfiguration Include="Release|x64">
+      <Configuration>Release</Configuration>
+      <Platform>x64</Platform>
+    </ProjectConfiguration>
+  </ItemGroup>
+  <PropertyGroup Label="Globals">
+    <VCProjectVersion>16.0</VCProjectVersion>
+    <Keyword>Win32Proj</Keyword>
+    <ProjectGuid>{0045d7ad-3f26-4b87-81cb-78d18839596d}</ProjectGuid>
+    <RootNamespace>LGIddHelper</RootNamespace>
+    <WindowsTargetPlatformVersion>10.0.22621.0</WindowsTargetPlatformVersion>
+  </PropertyGroup>
+  <Import Project="$(VCTargetsPath)\Microsoft.Cpp.Default.props" />
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <UseDebugLibraries>true</UseDebugLibraries>
+    <PlatformToolset>v143</PlatformToolset>
+    <CharacterSet>Unicode</CharacterSet>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <UseDebugLibraries>false</UseDebugLibraries>
+    <PlatformToolset>v143</PlatformToolset>
+    <WholeProgramOptimization>true</WholeProgramOptimization>
+    <CharacterSet>Unicode</CharacterSet>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|x64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <UseDebugLibraries>true</UseDebugLibraries>
+    <PlatformToolset>v143</PlatformToolset>
+    <CharacterSet>NotSet</CharacterSet>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|x64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <UseDebugLibraries>false</UseDebugLibraries>
+    <PlatformToolset>v143</PlatformToolset>
+    <WholeProgramOptimization>true</WholeProgramOptimization>
+    <CharacterSet>NotSet</CharacterSet>
+  </PropertyGroup>
+  <Import Project="$(VCTargetsPath)\Microsoft.Cpp.props" />
+  <ImportGroup Label="ExtensionSettings">
+  </ImportGroup>
+  <ImportGroup Label="Shared">
+  </ImportGroup>
+  <ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
+  </ImportGroup>
+  <ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
+  </ImportGroup>
+  <ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
+  </ImportGroup>
+  <ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Release|x64'">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
+  </ImportGroup>
+  <PropertyGroup Label="UserMacros" />
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
+    <ClCompile>
+      <WarningLevel>Level3</WarningLevel>
+      <SDLCheck>true</SDLCheck>
+      <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <ConformanceMode>true</ConformanceMode>
+      <AdditionalIncludeDirectories>$(SolutionDir)LGCommon;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+    </Link>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
+    <ClCompile>
+      <WarningLevel>Level3</WarningLevel>
+      <FunctionLevelLinking>true</FunctionLevelLinking>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <SDLCheck>true</SDLCheck>
+      <PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <ConformanceMode>true</ConformanceMode>
+      <AdditionalIncludeDirectories>$(SolutionDir)LGCommon;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <EnableCOMDATFolding>true</EnableCOMDATFolding>
+      <OptimizeReferences>true</OptimizeReferences>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+    </Link>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">
+    <ClCompile>
+      <WarningLevel>Level3</WarningLevel>
+      <SDLCheck>true</SDLCheck>
+      <PreprocessorDefinitions>_DEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <ConformanceMode>true</ConformanceMode>
+      <LanguageStandard>Default</LanguageStandard>
+      <LanguageStandard_C>Default</LanguageStandard_C>
+      <AdditionalIncludeDirectories>$(SolutionDir)LGCommon;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <RuntimeLibrary>MultiThreadedDebug</RuntimeLibrary>
+    </ClCompile>
+    <Link>
+      <SubSystem>Windows</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <AdditionalDependencies>%(AdditionalDependencies);Rpcrt4.lib;Userenv.lib;setupapi.lib</AdditionalDependencies>
+    </Link>
+    <PostBuildEvent>
+      <Command>if not exist "$(SolutionDir)$(Platform)\$(Configuration)\LGIdd" mkdir "$(SolutionDir)$(Platform)\$(Configuration)\LGIdd"
+copy /Y "$(TargetPath)" "$(SolutionDir)$(Platform)\$(Configuration)\LGIdd\"</Command>
+    </PostBuildEvent>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|x64'">
+    <ClCompile>
+      <WarningLevel>Level3</WarningLevel>
+      <FunctionLevelLinking>true</FunctionLevelLinking>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <SDLCheck>true</SDLCheck>
+      <PreprocessorDefinitions>NDEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <ConformanceMode>true</ConformanceMode>
+      <LanguageStandard>Default</LanguageStandard>
+      <LanguageStandard_C>Default</LanguageStandard_C>
+      <AdditionalIncludeDirectories>$(SolutionDir)LGCommon;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
+    </ClCompile>
+    <Link>
+      <SubSystem>Windows</SubSystem>
+      <EnableCOMDATFolding>true</EnableCOMDATFolding>
+      <OptimizeReferences>true</OptimizeReferences>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <AdditionalDependencies>%(AdditionalDependencies);Rpcrt4.lib;Userenv.lib;setupapi.lib</AdditionalDependencies>
+    </Link>
+    <PostBuildEvent>
+      <Command>if not exist "$(SolutionDir)$(Platform)\$(Configuration)\LGIdd" mkdir "$(SolutionDir)$(Platform)\$(Configuration)\LGIdd"
+copy /Y "$(TargetPath)" "$(SolutionDir)$(Platform)\$(Configuration)\LGIdd\"</Command>
+    </PostBuildEvent>
+  </ItemDefinitionGroup>
+  <ItemGroup>
+    <ClCompile Include="$(SolutionDir)LGCommon\*.cpp" />
+    <ClCompile Include="CPipeClient.cpp" />
+    <ClCompile Include="main.cpp" />
+  </ItemGroup>
+  <ItemGroup>
+    <CLInclude Include="$(SolutionDir)LGCommon\*.h" />
+    <ClInclude Include="CPipeClient.h" />
+  </ItemGroup>
+  <ItemGroup>
+    <None Include="packages.config" />
+  </ItemGroup>
+  <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
+  <ImportGroup Label="ExtensionTargets" />
+  <Target Name="GenerateVersionInfo" BeforeTargets="ClCompile">
+    <Exec Command="&quot;$(Git)&quot; describe --always --abbrev=10 --dirty=+ --tags" ConsoleToMSBuild="true">
+      <Output TaskParameter="ConsoleOutput" PropertyName="GitVersion" />
+    </Exec>
+    <ItemGroup>
+      <VersionInfoLines Include="#define LG_VERSION_STR &quot;$(GitVersion)&quot;" />
+      <VersionInfoLines Include="#define LG_CURRENT_YEAR $(CurrentYear)" />
+    </ItemGroup>
+    <WriteLinesToFile File="VersionInfo.h" Lines="@(VersionInfoLines)" Overwrite="true" />
+  </Target>
+  <Target Name="Build" DependsOnTargets="$(BuildDependsOn)" />
+  <PropertyGroup>
+    <CurrentYear>$([System.DateTime]::Now.ToString("yyyy"))</CurrentYear>
+    <BuildDependsOn>
+      GenerateVersionInfo;
+      $(BuildDependsOn);
+    </BuildDependsOn>
+  </PropertyGroup>
+  <Target Name="EnsureNuGetPackageBuildImports" BeforeTargets="PrepareForBuild">
+    <PropertyGroup>
+      <ErrorText>This project references NuGet package(s) that are missing on this computer. Use NuGet Package Restore to download them.  For more information, see http://go.microsoft.com/fwlink/?LinkID=322105. The missing file is {0}.</ErrorText>
+    </PropertyGroup>
+    <Error Condition="!Exists('..\packages\MSBuilder.Git.0.3.0\build\MSBuilder.Git.props')" Text="$([System.String]::Format('$(ErrorText)', '..\packages\MSBuilder.Git.0.3.0\build\MSBuilder.Git.props'))" />
+  </Target>
+</Project>

idd/LGIddHelper/LGIddHelper.vcxproj.filters

@@ -0,0 +1,29 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <ItemGroup>
+    <Filter Include="Source Files">
+      <UniqueIdentifier>{4FC737F1-C7A5-4376-A066-2A32D752A2FF}</UniqueIdentifier>
+      <Extensions>cpp;c;cc;cxx;c++;cppm;ixx;def;odl;idl;hpj;bat;asm;asmx</Extensions>
+    </Filter>
+    <Filter Include="Header Files">
+      <UniqueIdentifier>{93995380-89BD-4b04-88EB-625FBE52EBFB}</UniqueIdentifier>
+      <Extensions>h;hh;hpp;hxx;h++;hm;inl;inc;ipp;xsd</Extensions>
+    </Filter>
+    <Filter Include="Resource Files">
+      <UniqueIdentifier>{67DA6AB6-F800-4c08-8B7A-83BB121AAD01}</UniqueIdentifier>
+      <Extensions>rc;ico;cur;bmp;dlg;rc2;rct;bin;rgs;gif;jpg;jpeg;jpe;resx;tiff;tif;png;wav;mfcribbon-ms</Extensions>
+    </Filter>
+  </ItemGroup>
+  <ItemGroup>
+    <ClCompile Include="main.cpp">
+      <Filter>Source Files</Filter>
+    </ClCompile>
+    <ClCompile Include="$(SolutionDir)LGCommon\*.cpp" />
+  </ItemGroup>
+  <ItemGroup>
+    <CLInclude Include="$(SolutionDir)LGCommon\*.h" />
+  </ItemGroup>
+  <ItemGroup>
+    <None Include="packages.config" />
+  </ItemGroup>
+</Project>

idd/LGIddHelper/VersionInfo.h

@@ -0,0 +1,2 @@
+#define LG_VERSION_STR "B7-25-gbf59e45118+"
+#define LG_CURRENT_YEAR 2025

idd/LGIddHelper/main.cpp

@@ -0,0 +1,421 @@
+#include <Windows.h>
+#include <wrl.h>
+#include <UserEnv.h>
+
+#include <vector>
+#include <string>
+
+using namespace Microsoft::WRL::Wrappers;
+using namespace Microsoft::WRL::Wrappers::HandleTraits;
+
+#include "CDebug.h"
+#include "VersionInfo.h"
+#include "CPipeClient.h"
+
+#define SVCNAME "Looking Glass (IDD Helper)"
+
+static SERVICE_STATUS_HANDLE l_svcStatusHandle;
+static SERVICE_STATUS        l_svcStatus;
+static HandleT<EventTraits>  l_svcStopEvent;
+
+bool HandleService();
+static void WINAPI SvcMain(DWORD dwArgc, LPTSTR* lpszArgv);
+static void WINAPI SvcCtrlHandler(DWORD dwControl);
+static void ReportSvcStatus(DWORD dwCurrentState, DWORD dwWin32ExitCode, DWORD dwWaitHint);
+
+static std::string               l_executable;
+static HandleT<HANDLENullTraits> l_process;
+static HandleT<EventTraits>      l_exitEvent;
+static std::string               l_exitEventName;
+
+static void Launch();
+
+LRESULT CALLBACK DummyWndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
+{
+  return DefWindowProc(hwnd, msg, wParam, lParam);
+}
+
+int WINAPI WinMain(_In_ HINSTANCE hInstance, _In_opt_ HINSTANCE hPrevInstance, _In_ LPSTR lpCmdLine, _In_ int nShowCmd)
+{
+  g_debug.Init("looking-glass-iddhelper");
+  DEBUG_INFO("Looking Glass IDD Helper (" LG_VERSION_STR ")");
+
+  char buffer[MAX_PATH];
+  DWORD result = GetModuleFileNameA(NULL, buffer, MAX_PATH);
+  if (result == 0)
+  {
+    DEBUG_ERROR("Failed to get the executable path");
+    return EXIT_FAILURE;
+  }  
+  l_executable = buffer;
+
+  int argc = 0;
+  LPWSTR * wargv = CommandLineToArgvW(GetCommandLineW(), &argc);
+  std::vector<std::string> args;
+  args.reserve(argc);
+  for (int i = 0; i < argc; ++i)
+  {
+    size_t len = wcslen(wargv[i]);
+    size_t bufSize = (len + 1) * 2;
+    std::vector<char> buffer(bufSize);
+
+    size_t converted = 0;
+    errno_t err = wcstombs_s(&converted, buffer.data(), bufSize, wargv[i], bufSize - 1);
+    if (err != 0)
+    {
+      DEBUG_ERROR("Conversion failed");
+      return EXIT_FAILURE;
+    }
+
+    args.emplace_back(buffer.data());
+  }
+  LocalFree(wargv);
+
+  if (argc == 1)
+  {
+    if (!HandleService())
+      return EXIT_FAILURE;
+    return EXIT_SUCCESS;
+  }
+
+  // child process
+  if (argc != 2)
+  {
+    // the one and only value we should see is the exit event name
+    DEBUG_ERROR("Invalid invocation");
+    return EXIT_FAILURE;
+  }
+
+  l_exitEvent.Attach(OpenEvent(SYNCHRONIZE, FALSE, args[1].c_str()));
+  if (!l_exitEvent.IsValid())
+  {
+    DEBUG_ERROR_HR(GetLastError(), "Failed to open the exit event: %s", args[1].c_str());
+    return EXIT_FAILURE;
+  }
+
+  WNDCLASSEX wx = {};
+  wx.cbSize        = sizeof(WNDCLASSEX);
+  wx.lpfnWndProc   = DummyWndProc;
+  wx.hInstance     = hInstance;
+  wx.lpszClassName = "DUMMY_CLASS";
+  wx.hIcon         = LoadIcon(NULL, IDI_APPLICATION);
+  wx.hIconSm       = LoadIcon(NULL, IDI_APPLICATION);
+  wx.hCursor       = LoadCursor(NULL, IDC_ARROW);
+  wx.hbrBackground = (HBRUSH)COLOR_APPWORKSPACE;
+  ATOM aclass;
+  if (!(aclass = RegisterClassEx(&wx)))
+  {
+    DEBUG_ERROR("Failed to register message window class");
+    return EXIT_FAILURE;
+  }
+
+  HWND msgWnd = CreateWindowExA(0, MAKEINTATOM(aclass), NULL,
+    0, 0, 0, 0, 0, NULL, NULL, hInstance, NULL);
+
+  bool running = g_pipe.Init();
+  while (running)
+  {
+    switch (MsgWaitForMultipleObjects(1, l_exitEvent.GetAddressOf(),
+      FALSE, INFINITE, QS_ALLINPUT))
+    {
+      case WAIT_OBJECT_0:
+        running = false;
+        break;
+
+      case WAIT_OBJECT_0 + 1:
+      {
+        MSG msg;
+        if (GetMessage(&msg, NULL, 0, 0))
+        {
+          TranslateMessage(&msg);
+          DispatchMessage(&msg);
+        }
+        break;
+      }
+
+      case WAIT_FAILED:
+        DEBUG_ERROR_HR(GetLastError(), "MsgWaitForMultipleObjects Failed");
+        running = false;
+        break;
+    }    
+  }
+  g_pipe.DeInit();
+
+  DestroyWindow(msgWnd);
+  return EXIT_SUCCESS;
+}
+
+bool HandleService()
+{  
+  SERVICE_TABLE_ENTRY DispatchTable[] =
+  {
+    { (char *)SVCNAME, SvcMain },
+    { NULL, NULL }
+  };
+
+  if (StartServiceCtrlDispatcher(DispatchTable) == FALSE)
+  {
+    DEBUG_ERROR_HR(GetLastError(), "StartServiceCtrlDispatcher Failed");
+    return false;
+  }
+
+  return true;
+}
+
+static void WINAPI SvcCtrlHandler(DWORD dwControl)
+{
+  switch (dwControl)
+  {
+    case SERVICE_CONTROL_STOP:
+      ReportSvcStatus(SERVICE_STOP_PENDING, NO_ERROR, 0);
+      SetEvent(l_svcStopEvent.Get());
+      return;
+
+    default:
+      break;
+  }
+
+  ReportSvcStatus(l_svcStatus.dwCurrentState, NO_ERROR, 0);
+}
+
+static void WINAPI SvcMain(DWORD dwArgc, LPTSTR* lpszArgv)
+{
+  l_svcStatus.dwServiceType   = SERVICE_WIN32_OWN_PROCESS;
+  l_svcStatus.dwWin32ExitCode = 0;
+
+  l_svcStatusHandle = RegisterServiceCtrlHandler(SVCNAME, SvcCtrlHandler);
+  if (!l_svcStatusHandle)
+  {
+    DEBUG_ERROR_HR(GetLastError(), "RegisterServiceCtrlHandler Failed");
+    return;
+  }
+
+  if (!CPipeClient::IsLGIddDeviceAttached())
+  {
+    DEBUG_INFO("Looking Glass Indirect Display Device not found, not starting.");
+    ReportSvcStatus(SERVICE_STOPPED, NO_ERROR, 0);
+    return;
+  }
+
+  ReportSvcStatus(SERVICE_START_PENDING, NO_ERROR, 0);
+  l_svcStopEvent.Attach(CreateEvent(NULL, TRUE, FALSE, NULL));
+  if (!l_svcStopEvent.IsValid())
+  {
+    DEBUG_ERROR_HR(GetLastError(), "CreateEvent Failed");
+    ReportSvcStatus(SERVICE_STOPPED, NO_ERROR, 0);
+    return;
+  }
+
+  UUID uuid;
+  RPC_CSTR uuidStr;
+  RPC_STATUS status = UuidCreate(&uuid);
+  if (status != RPC_S_OK && status != RPC_S_UUID_LOCAL_ONLY && status != RPC_S_UUID_NO_ADDRESS)
+  {
+    DEBUG_ERROR("UuidCreate Failed: 0x%x", status);
+    ReportSvcStatus(SERVICE_STOPPED, NO_ERROR, 0);
+    return;
+  }
+
+  if (UuidToString(&uuid, &uuidStr) == RPC_S_OK)
+  {
+    l_exitEventName = "Global\\";
+    l_exitEventName += (const char *)uuidStr;
+    RpcStringFree(&uuidStr);
+
+    l_exitEvent.Attach(CreateEvent(NULL, FALSE, FALSE, l_exitEventName.c_str()));
+    if (!l_exitEvent.IsValid())
+    {
+      DEBUG_ERROR_HR(GetLastError(), "CreateEvent Failed");
+      ReportSvcStatus(SERVICE_STOPPED, NO_ERROR, 0);
+      return;
+    }
+  }
+
+  ReportSvcStatus(SERVICE_RUNNING, NO_ERROR, 0);
+  bool running = true;
+  while (running)
+  {
+    ULONGLONG launchTime = 0ULL;
+
+    DWORD interactiveSession = WTSGetActiveConsoleSessionId();
+    if (interactiveSession != 0 && interactiveSession != 0xFFFFFFFF)
+    {
+      if (!CPipeClient::IsLGIddDeviceAttached())
+      {
+        DEBUG_INFO("Looking Glass Indirect Display Device has gone away");
+        ReportSvcStatus(SERVICE_STOPPED, NO_ERROR, 0);
+        return;
+      }
+
+      Launch();
+      launchTime = GetTickCount64();
+    }
+
+    HANDLE waitOn[] = { l_svcStopEvent.Get(), l_process.Get()};
+    DWORD count     = 2;
+    DWORD duration  = INFINITE;
+
+    if (!l_process.IsValid())
+    {
+      count    = 1;
+      duration = 1000;
+    }
+
+    switch (WaitForMultipleObjects(count, waitOn, FALSE, duration))
+    {
+      // stop requested by the service manager
+      case WAIT_OBJECT_0:
+        running = false;
+        break;
+
+      // child application exited
+      case WAIT_OBJECT_0 + 1:
+      {
+        DWORD code;
+        if (!GetExitCodeProcess(l_process.Get(), &code))
+        {
+          DEBUG_ERROR_HR(GetLastError(), "GetExitCodeProcess Failed");
+          break;
+        }
+
+        DEBUG_INFO("Child process exited with code 0x%lx", code);
+        l_process.Close();
+        break;
+      }
+
+      case WAIT_FAILED:
+        DEBUG_ERROR_HR(GetLastError(), "Failed to WaitForMultipleObjects");
+        running = false;
+        break;
+    }
+
+    if (!running)
+      break;
+
+    Sleep(1000);
+  }
+
+  SetEvent(l_exitEvent.Get());
+  ReportSvcStatus(SERVICE_STOPPED, NO_ERROR, 0);
+}
+
+static void ReportSvcStatus(DWORD dwCurrentState, DWORD dwWin32ExitCode, DWORD dwWaitHint)
+{
+  static DWORD dwCheckPoint   = 0;
+  l_svcStatus.dwCurrentState  = dwCurrentState;
+  l_svcStatus.dwWin32ExitCode = dwWin32ExitCode;
+  l_svcStatus.dwWaitHint      = dwWaitHint;
+
+  if (dwCurrentState == SERVICE_START_PENDING)
+    l_svcStatus.dwControlsAccepted = 0;
+  else
+    l_svcStatus.dwControlsAccepted = SERVICE_ACCEPT_STOP;
+
+  if ((dwCurrentState == SERVICE_RUNNING) || (dwCurrentState == SERVICE_STOPPED))
+    l_svcStatus.dwCheckPoint = 0;
+  else
+    l_svcStatus.dwCheckPoint = ++dwCheckPoint;
+
+  SetServiceStatus(l_svcStatusHandle, &l_svcStatus);
+}
+
+//static void 
+
+static bool EnablePriv(const char * name)
+{
+  return true;
+}
+
+static void DisablePriv(const char * name)
+{
+
+}
+
+static void Launch()
+{
+  l_process.Close();
+
+  HandleT<HANDLENullTraits> sysToken;
+  if (!OpenProcessToken(GetCurrentProcess(), TOKEN_QUERY | TOKEN_DUPLICATE |
+    TOKEN_ASSIGN_PRIMARY | TOKEN_ADJUST_SESSIONID | TOKEN_ADJUST_DEFAULT,
+    sysToken.GetAddressOf()))
+  {
+    DEBUG_ERROR_HR(GetLastError(), "OpenProcessToken failed");
+    return;
+  }
+
+  HandleT<HANDLENullTraits> token;
+  if (!DuplicateTokenEx(sysToken.Get(), 0, NULL, SecurityAnonymous,
+    TokenPrimary, token.GetAddressOf()))
+  {
+    DEBUG_ERROR_HR(GetLastError(), "DuplicateTokenEx failed");
+    return;
+  }
+
+  DWORD origSessionID, targetSessionID, returnedLen;
+  GetTokenInformation(token.Get(), TokenSessionId, &origSessionID,
+    sizeof(origSessionID), &returnedLen);
+
+  targetSessionID = WTSGetActiveConsoleSessionId();
+  if (origSessionID != targetSessionID)
+  {
+    if (!SetTokenInformation(token.Get(), TokenSessionId,
+      &targetSessionID, sizeof(targetSessionID)))
+    {
+      DEBUG_ERROR_HR(GetLastError(), "SetTokenInformation failed");
+      return;
+    }
+  }
+  
+  LPVOID env = NULL;
+  if (!CreateEnvironmentBlock(&env, token.Get(), TRUE))
+  {
+    DEBUG_ERROR_HR(GetLastError(), "CreateEnvironmentBlock failed");
+    return;
+  }
+
+  if (!EnablePriv(SE_INCREASE_QUOTA_NAME))
+  {
+    DEBUG_ERROR("Failed to enable %s", SE_INCREASE_QUOTA_NAME);
+    return;
+  }
+
+  PROCESS_INFORMATION pi = {0};
+  STARTUPINFO si = {0};
+  si.cb          = sizeof(si);
+  si.dwFlags     = STARTF_USESHOWWINDOW;
+  si.wShowWindow = SW_SHOW;
+  si.lpDesktop   = (LPSTR)"WinSta0\\Default";
+
+  char * cmdLine = NULL;
+  char cmdBuf[128];
+  if (l_exitEvent.IsValid())
+  {
+    snprintf(cmdBuf, sizeof(cmdBuf), "LGIddHelper.exe %s",
+      l_exitEventName.c_str());
+    cmdLine = cmdBuf;
+  }
+
+  if (!CreateProcessAsUserA(
+    token.Get(),
+    l_executable.c_str(),
+    cmdLine,
+    NULL,
+    NULL,
+    FALSE,
+    DETACHED_PROCESS | HIGH_PRIORITY_CLASS | CREATE_UNICODE_ENVIRONMENT,
+    env,
+    NULL,
+    &si,
+    &pi
+  ))
+  {
+    DEBUG_ERROR_HR(GetLastError(), "CreateProcessAsUser failed");
+    return;
+  }
+
+  DisablePriv(SE_INCREASE_QUOTA_NAME);
+
+  l_process.Attach(pi.hProcess);
+  CloseHandle(pi.hThread);
+}

idd/LGIddHelper/packages.config

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<packages>
+  <package id="MSBuilder.Git" version="0.3.0" targetFramework="native" />
+</packages>