CmdPal: Add low-level keyboard hook for global hotkey (#38250)

Adds the ability to make the global CmdPal hotkey a low-level hook. This is needed for `win+space`, `win+r`, et al. 

I've only added this to the root hotkey. Other hotkeys will still use the normal `RegisterHotkey` ones. We can re-evaluate this for 0.2+.



Originally: https://github.com/zadjii-msft/PowerToys/issues/349

Solves: https://github.com/microsoft/PowerToys/issues/38297

---------

Co-authored-by: Mike Griese <migrie@microsoft.com>

src/modules/cmdpal/CmdPalKeyboardService/CmdPalKeyboardService.def

@@ -0,0 +1,3 @@
+EXPORTS
+DllCanUnloadNow = WINRT_CanUnloadNow                    PRIVATE
+DllGetActivationFactory = WINRT_GetActivationFactory    PRIVATE

src/modules/cmdpal/CmdPalKeyboardService/CmdPalKeyboardService.rc

@@ -0,0 +1,40 @@
+#include <windows.h>
+#include "resource.h"
+#include "../../../common/version/version.h"
+
+#define APSTUDIO_READONLY_SYMBOLS
+#include "winres.h"
+#undef APSTUDIO_READONLY_SYMBOLS
+
+1 VERSIONINFO
+FILEVERSION FILE_VERSION
+PRODUCTVERSION PRODUCT_VERSION
+FILEFLAGSMASK VS_FFI_FILEFLAGSMASK
+#ifdef _DEBUG
+FILEFLAGS VS_FF_DEBUG
+#else
+FILEFLAGS 0x0L
+#endif
+FILEOS VOS_NT_WINDOWS32
+FILETYPE VFT_DLL
+FILESUBTYPE VFT2_UNKNOWN
+BEGIN
+    BLOCK "StringFileInfo"
+    BEGIN
+        BLOCK "040904b0" // US English (0x0409), Unicode (0x04B0) charset
+        BEGIN
+            VALUE "CompanyName", COMPANY_NAME
+            VALUE "FileDescription", FILE_DESCRIPTION
+            VALUE "FileVersion", FILE_VERSION_STRING
+            VALUE "InternalName", INTERNAL_NAME
+            VALUE "LegalCopyright", COPYRIGHT_NOTE
+            VALUE "OriginalFilename", ORIGINAL_FILENAME
+            VALUE "ProductName", PRODUCT_NAME
+            VALUE "ProductVersion", PRODUCT_VERSION_STRING
+        END
+    END
+    BLOCK "VarFileInfo"
+    BEGIN
+        VALUE "Translation", 0x409, 1200 // US English (0x0409), Unicode (1200) charset
+    END
+END

src/modules/cmdpal/CmdPalKeyboardService/CmdPalKeyboardService.vcxproj

@@ -0,0 +1,187 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project DefaultTargets="Build" ToolsVersion="15.0"
+  xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <Import Project="..\..\..\..\packages\Microsoft.Windows.CppWinRT.2.0.240111.5\build\native\Microsoft.Windows.CppWinRT.props" Condition="Exists('..\..\..\..\packages\Microsoft.Windows.CppWinRT.2.0.240111.5\build\native\Microsoft.Windows.CppWinRT.props')" />
+  <PropertyGroup Label="Globals">
+    <CppWinRTRootNamespaceAutoMerge>true</CppWinRTRootNamespaceAutoMerge>
+    <CppWinRTGenerateWindowsMetadata>true</CppWinRTGenerateWindowsMetadata>
+    <ProjectGuid>{5f63c743-f6ce-4dba-a200-2b3f8a14e8c2}</ProjectGuid>
+    <ProjectName>CmdPalKeyboardService</ProjectName>
+    <RootNamespace>CmdPalKeyboardService</RootNamespace>
+    <AppxPackage>false</AppxPackage>
+  </PropertyGroup>
+
+  <!-- BEGIN common.build.pre.props -->
+  <PropertyGroup Label="Configuration">
+    <EnableHybridCRT>true</EnableHybridCRT>
+    <UseCrtSDKReferenceStaticWarning Condition="'$(EnableHybridCRT)'=='true'">false</UseCrtSDKReferenceStaticWarning>
+  </PropertyGroup>
+  <!-- END common.build.pre.props -->
+  <!-- BEGIN cppwinrt.build.pre.props -->
+  <PropertyGroup Label="Globals">
+    <CppWinRTEnabled>true</CppWinRTEnabled>
+    <CppWinRTOptimized>true</CppWinRTOptimized>
+    <DefaultLanguage>en-US</DefaultLanguage>
+    <MinimumVisualStudioVersion>17.0</MinimumVisualStudioVersion>
+    <ApplicationTypeRevision>10.0</ApplicationTypeRevision>
+  </PropertyGroup>
+  <PropertyGroup>
+    <MinimalCoreWin>true</MinimalCoreWin>
+    <AppContainerApplication>true</AppContainerApplication>
+    <WindowsStoreApp>true</WindowsStoreApp>
+    <ApplicationType>Windows Store</ApplicationType>
+    <UseCrtSDKReference Condition="'$(EnableHybridCRT)'=='true'">false</UseCrtSDKReference> <!-- The SDK reference breaks the Hybrid CRT -->
+  </PropertyGroup>
+  <PropertyGroup>
+    <!-- We have to use the Desktop platform for Hybrid CRT to work. -->
+    <_VC_Target_Library_Platform>Desktop</_VC_Target_Library_Platform>
+    <_NoWinAPIFamilyApp>true</_NoWinAPIFamilyApp>
+  </PropertyGroup>
+  <!-- END cppwinrt.build.pre.props -->
+
+  <Import Project="$(VCTargetsPath)\Microsoft.Cpp.Default.props" />
+  <PropertyGroup Label="Configuration">
+    <ConfigurationType>DynamicLibrary</ConfigurationType>
+    <PlatformToolset>v143</PlatformToolset>
+    <CharacterSet>Unicode</CharacterSet>
+    <GenerateManifest>false</GenerateManifest>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)'=='Debug'" Label="Configuration">
+    <UseDebugLibraries>true</UseDebugLibraries>
+    <LinkIncremental>true</LinkIncremental>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)'=='Release'" Label="Configuration">
+    <UseDebugLibraries>false</UseDebugLibraries>
+    <WholeProgramOptimization>true</WholeProgramOptimization>
+    <LinkIncremental>false</LinkIncremental>
+  </PropertyGroup>
+
+  <Import Project="$(VCTargetsPath)\Microsoft.Cpp.props" />
+
+  <ImportGroup Label="ExtensionSettings">
+  </ImportGroup>
+  <ImportGroup Label="Shared">
+  </ImportGroup>
+  <ImportGroup Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
+  </ImportGroup>
+  <ImportGroup Label="PropertySheets">
+    <Import Project="PropertySheet.props" />
+  </ImportGroup>
+  <PropertyGroup Label="UserMacros" />
+  <PropertyGroup>
+    <TargetName>CmdPalKeyboardService</TargetName>
+    <OutDir>..\..\..\..\$(Platform)\$(Configuration)\</OutDir>
+  </PropertyGroup>
+  <ItemDefinitionGroup>
+    <ClCompile>
+      <PrecompiledHeaderOutputFile>$(IntDir)pch.pch</PrecompiledHeaderOutputFile>
+      <WarningLevel>Level4</WarningLevel>
+      <AdditionalOptions>%(AdditionalOptions) /bigobj</AdditionalOptions>
+      <PreprocessorDefinitions>_WINRT_DLL;WINRT_LEAN_AND_MEAN;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalIncludeDirectories>../../..;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <AdditionalUsingDirectories>$(WindowsSDK_WindowsMetadata);$(AdditionalUsingDirectories)</AdditionalUsingDirectories>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <GenerateWindowsMetadata>false</GenerateWindowsMetadata>
+      <ModuleDefinitionFile>CmdPalKeyboardService.def</ModuleDefinitionFile>
+      <AdditionalDependencies>Shell32.lib;user32.lib;%(AdditionalDependencies)</AdditionalDependencies>
+    </Link>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)'=='Debug'">
+    <ClCompile>
+      <PreprocessorDefinitions>_DEBUG;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+    </ClCompile>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)'=='Release'">
+    <ClCompile>
+      <PreprocessorDefinitions>NDEBUG;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+    </ClCompile>
+    <Link>
+      <EnableCOMDATFolding>true</EnableCOMDATFolding>
+      <OptimizeReferences>true</OptimizeReferences>
+    </Link>
+  </ItemDefinitionGroup>
+  <ItemGroup>
+    <ClInclude Include="pch.h" />
+    <ClInclude Include="KeyboardListener.h">
+      <DependentUpon>KeyboardListener.idl</DependentUpon>
+    </ClInclude>
+    <ClInclude Include="resource.h" />
+  </ItemGroup>
+  <ItemGroup>
+    <ClCompile Include="pch.cpp">
+      <PrecompiledHeader>Create</PrecompiledHeader>
+    </ClCompile>
+    <ClCompile Include="KeyboardListener.cpp">
+      <DependentUpon>KeyboardListener.idl</DependentUpon>
+    </ClCompile>
+    <ClCompile Include="$(GeneratedFilesDir)module.g.cpp" />
+  </ItemGroup>
+  <ItemGroup>
+    <Midl Include="KeyboardListener.idl" />
+  </ItemGroup>
+  <ItemGroup>
+    <None Include="packages.config" />
+    <None Include="CmdPalKeyboardService.def" />
+  </ItemGroup>
+  <ItemGroup>
+    <None Include="PropertySheet.props" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <ResourceCompile Include="CmdPalKeyboardService.rc" />
+  </ItemGroup>
+  <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
+  <Import Project="..\..\..\..\deps\spdlog.props" />
+  <ImportGroup Label="ExtensionTargets">
+    <Import Project="..\..\..\..\packages\Microsoft.Windows.CppWinRT.2.0.240111.5\build\native\Microsoft.Windows.CppWinRT.targets" Condition="Exists('..\..\..\..\packages\Microsoft.Windows.CppWinRT.2.0.240111.5\build\native\Microsoft.Windows.CppWinRT.targets')" />
+  </ImportGroup>
+  <Target Name="EnsureNuGetPackageBuildImports" BeforeTargets="PrepareForBuild">
+    <PropertyGroup>
+      <ErrorText>This project references NuGet package(s) that are missing on this computer. Use NuGet Package Restore to download them.  For more information, see http://go.microsoft.com/fwlink/?LinkID=322105. The missing file is {0}.</ErrorText>
+    </PropertyGroup>
+    <Error Condition="!Exists('..\..\..\..\packages\Microsoft.Windows.CppWinRT.2.0.240111.5\build\native\Microsoft.Windows.CppWinRT.props')" Text="$([System.String]::Format('$(ErrorText)', '..\..\..\..\packages\Microsoft.Windows.CppWinRT.2.0.240111.5\build\native\Microsoft.Windows.CppWinRT.props'))" />
+    <Error Condition="!Exists('..\..\..\..\packages\Microsoft.Windows.CppWinRT.2.0.240111.5\build\native\Microsoft.Windows.CppWinRT.targets')" Text="$([System.String]::Format('$(ErrorText)', '..\..\..\..\packages\Microsoft.Windows.CppWinRT.2.0.240111.5\build\native\Microsoft.Windows.CppWinRT.targets'))" />
+  </Target>
+
+  <!-- BEGIN common.build.post.props -->
+  <!--
+    The Hybrid CRT model statically links the runtime and STL and dynamically
+    links the UCRT instead of the VC++ CRT. The UCRT ships with Windows.
+    WinAppSDK asserts that this is "supported according to the CRT maintainer."
+
+    This must come before Microsoft.Cpp.targets because it manipulates ClCompile.RuntimeLibrary.
+  -->
+  <ItemDefinitionGroup Condition="'$(EnableHybridCRT)'=='true' and '$(Configuration)'=='Debug'">
+    <ClCompile>
+      <!-- We use MultiThreadedDebug, rather than MultiThreadedDebugDLL, to avoid DLL dependencies on VCRUNTIME140d.dll and MSVCP140d.dll. -->
+      <RuntimeLibrary>MultiThreadedDebug</RuntimeLibrary>
+    </ClCompile>
+    <Link>
+      <!-- Link statically against the runtime and STL, but link dynamically against the CRT by ignoring the static CRT
+           lib and instead linking against the Universal CRT DLL import library. This "hybrid" linking mechanism is
+           supported according to the CRT maintainer. Dynamic linking against the CRT makes the binaries a bit smaller
+           than they would otherwise be if the CRT, runtime, and STL were all statically linked in. -->
+      <IgnoreSpecificDefaultLibraries>%(IgnoreSpecificDefaultLibraries);libucrtd.lib</IgnoreSpecificDefaultLibraries>
+      <AdditionalOptions>%(AdditionalOptions) /defaultlib:ucrtd.lib</AdditionalOptions>
+    </Link>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(EnableHybridCRT)'=='true' and ('$(Configuration)'=='Release' or '$(Configuration)'=='AuditMode')">
+    <ClCompile>
+      <!-- We use MultiThreaded, rather than MultiThreadedDLL, to avoid DLL dependencies on VCRUNTIME140.dll and MSVCP140.dll. -->
+      <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
+    </ClCompile>
+    <Link>
+      <!-- Link statically against the runtime and STL, but link dynamically against the CRT by ignoring the static CRT
+           lib and instead linking against the Universal CRT DLL import library. This "hybrid" linking mechanism is
+           supported according to the CRT maintainer. Dynamic linking against the CRT makes the binaries a bit smaller
+           than they would otherwise be if the CRT, runtime, and STL were all statically linked in. -->
+      <IgnoreSpecificDefaultLibraries>%(IgnoreSpecificDefaultLibraries);libucrt.lib</IgnoreSpecificDefaultLibraries>
+      <AdditionalOptions>%(AdditionalOptions) /defaultlib:ucrt.lib</AdditionalOptions>
+    </Link>
+  </ItemDefinitionGroup>
+  <!-- END common.build.post.props -->
+
+</Project>

src/modules/cmdpal/CmdPalKeyboardService/CmdPalKeyboardService.vcxproj.filters

@@ -0,0 +1,36 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project ToolsVersion="15.0"
+  xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <ItemGroup>
+    <Filter Include="Resources">
+      <UniqueIdentifier>accd3aa8-1ba0-4223-9bbe-0c431709210b</UniqueIdentifier>
+      <Extensions>rc;ico;cur;bmp;dlg;rc2;rct;bin;rgs;gif;jpg;jpeg;jpe;resx;tga;tiff;tif;png;wav;mfcribbon-ms</Extensions>
+    </Filter>
+    <Filter Include="Generated Files">
+      <UniqueIdentifier>{926ab91d-31b4-48c3-b9a4-e681349f27f0}</UniqueIdentifier>
+    </Filter>
+  </ItemGroup>
+  <ItemGroup>
+    <ClCompile Include="pch.cpp" />
+    <ClCompile Include="$(GeneratedFilesDir)module.g.cpp" />
+  </ItemGroup>
+  <ItemGroup>
+    <ClInclude Include="pch.h" />
+    <ClInclude Include="resource.h" />
+  </ItemGroup>
+  <ItemGroup>
+    <Midl Include="KeyboardListener.idl" />
+  </ItemGroup>
+  <ItemGroup>
+    <None Include="CmdPalKeyboardService.def" />
+    <None Include="packages.config" />
+  </ItemGroup>
+  <ItemGroup>
+    <None Include="PropertySheet.props" />
+  </ItemGroup>
+  <ItemGroup>
+    <ResourceCompile Include="CmdPalKeyboardService.rc">
+      <Filter>Resources</Filter>
+    </ResourceCompile>
+  </ItemGroup>
+</Project>

src/modules/cmdpal/CmdPalKeyboardService/KeyboardListener.cpp

@@ -0,0 +1,165 @@
+#include "pch.h"
+#include "KeyboardListener.h"
+#include "KeyboardListener.g.cpp"
+
+// #include <common/logger/logger.h>
+// #include <common/utils/logger_helper.h>
+#include <common/utils/winapi_error.h>
+
+namespace
+{
+}
+
+namespace winrt::CmdPalKeyboardService::implementation
+{
+    KeyboardListener::KeyboardListener()
+    {
+        s_instance = this;
+    }
+
+    void KeyboardListener::Start()
+    {
+#if defined(DISABLE_LOWLEVEL_HOOKS_WHEN_DEBUGGED)
+        const bool hook_disabled = IsDebuggerPresent();
+#else
+        const bool hook_disabled = false;
+#endif
+        if (!hook_disabled)
+        {
+            if (!s_llKeyboardHook)
+            {
+                s_llKeyboardHook = SetWindowsHookExW(WH_KEYBOARD_LL, LowLevelKeyboardProc, NULL, NULL);
+                if (!s_llKeyboardHook)
+                {
+                    DWORD errorCode = GetLastError();
+                    show_last_error_message(L"SetWindowsHookEx", errorCode, L"CmdPalKeyboardService");
+                }
+            }
+        }
+    }
+
+    void KeyboardListener::Stop()
+    {
+        if (s_llKeyboardHook && UnhookWindowsHookEx(s_llKeyboardHook))
+        {
+            s_llKeyboardHook = NULL;
+        }
+    }
+
+    void KeyboardListener::SetHotkeyAction(bool win, bool ctrl, bool shift, bool alt, uint8_t key, hstring const& id)
+    {
+        Hotkey hotkey = { .win = win, .ctrl = ctrl, .shift = shift, .alt = alt, .key = key };
+        std::unique_lock lock{ mutex };
+
+        HotkeyDescriptor desc = { .hotkey = hotkey, .id = std::wstring(id) };
+        hotkeyDescriptors.insert(desc);
+    }
+
+    void KeyboardListener::ClearHotkey(hstring const& id)
+    {
+        {
+            std::unique_lock lock{ mutex };
+            auto it = hotkeyDescriptors.begin();
+            while (it != hotkeyDescriptors.end())
+            {
+                if (it->id == id)
+                {
+                    it = hotkeyDescriptors.erase(it);
+                }
+                else
+                {
+                    ++it;
+                }
+            }
+        }
+    }
+
+    void KeyboardListener::ClearHotkeys()
+    {
+        {
+            std::unique_lock lock{ mutex };
+            auto it = hotkeyDescriptors.begin();
+            while (it != hotkeyDescriptors.end())
+            {
+                it = hotkeyDescriptors.erase(it);
+            }
+        }
+    }
+
+    void KeyboardListener::SetProcessCommand(ProcessCommand processCommand)
+    {
+        m_processCommandCb = [trigger = std::move(processCommand)](hstring const& id) {
+            trigger(id);
+        };
+    }
+
+    LRESULT KeyboardListener::DoLowLevelKeyboardProc(int nCode, WPARAM wParam, LPARAM lParam)
+    {
+        const auto& keyPressInfo = *reinterpret_cast<KBDLLHOOKSTRUCT*>(lParam);
+
+        if ((wParam != WM_KEYDOWN) && (wParam != WM_SYSKEYDOWN))
+        {
+            return CallNextHookEx(NULL, nCode, wParam, lParam);
+        }
+
+        Hotkey hotkey{
+            .win = (GetAsyncKeyState(VK_LWIN) & 0x8000) || (GetAsyncKeyState(VK_RWIN) & 0x8000),
+            .ctrl = static_cast<bool>(GetAsyncKeyState(VK_CONTROL) & 0x8000),
+            .shift = static_cast<bool>(GetAsyncKeyState(VK_SHIFT) & 0x8000),
+            .alt = static_cast<bool>(GetAsyncKeyState(VK_MENU) & 0x8000),
+            .key = static_cast<unsigned char>(keyPressInfo.vkCode)
+        };
+
+        if (hotkey == Hotkey{})
+        {
+            return CallNextHookEx(NULL, nCode, wParam, lParam);
+        }
+
+        bool do_action = false;
+        std::wstring actionId{};
+
+        {
+            // Hold the lock for the shortest possible duration
+            std::unique_lock lock{ mutex };
+            HotkeyDescriptor dummy{ .hotkey = hotkey };
+            auto it = hotkeyDescriptors.find(dummy);
+            if (it != hotkeyDescriptors.end())
+            {
+                do_action = true;
+                actionId = it->id;
+            }
+        }
+
+        if (do_action)
+        {
+            m_processCommandCb(hstring{ actionId });
+
+            // After invoking the hotkey send a dummy key to prevent Start Menu from activating
+            INPUT dummyEvent[1] = {};
+            dummyEvent[0].type = INPUT_KEYBOARD;
+            dummyEvent[0].ki.wVk = 0xFF;
+            dummyEvent[0].ki.dwFlags = KEYEVENTF_KEYUP;
+            SendInput(1, dummyEvent, sizeof(INPUT));
+
+            // Swallow the key press
+            return 1;
+        }
+
+        return CallNextHookEx(NULL, nCode, wParam, lParam);
+    }
+
+    LRESULT KeyboardListener::LowLevelKeyboardProc(int nCode, WPARAM wParam, LPARAM lParam)
+    {
+        if (s_instance == nullptr)
+        {
+            return CallNextHookEx(NULL, nCode, wParam, lParam);
+        }
+
+        if (nCode < 0)
+        {
+            return CallNextHookEx(NULL, nCode, wParam, lParam);
+        }
+
+        return s_instance->DoLowLevelKeyboardProc(nCode, wParam, lParam);
+    }
+}

src/modules/cmdpal/CmdPalKeyboardService/KeyboardListener.h

@@ -0,0 +1,67 @@
+#pragma once
+
+#include "KeyboardListener.g.h"
+#include <mutex>
+#include <spdlog/stopwatch.h>
+#include <set>
+
+namespace winrt::CmdPalKeyboardService::implementation
+{
+    struct KeyboardListener : KeyboardListenerT<KeyboardListener>
+    {
+        struct Hotkey
+        {
+            bool win = false;
+            bool ctrl = false;
+            bool shift = false;
+            bool alt = false;
+            unsigned char key = 0;
+
+            std::strong_ordering operator<=>(const Hotkey&) const = default;
+        };
+
+        struct HotkeyDescriptor
+        {
+            Hotkey hotkey;
+            std::wstring id;
+
+            bool operator<(const HotkeyDescriptor& other) const
+            {
+                return hotkey < other.hotkey;
+            };
+        };
+
+        KeyboardListener();
+
+        void Start();
+        void Stop();
+        void SetHotkeyAction(bool win, bool ctrl, bool shift, bool alt, uint8_t key, hstring const& id);
+        void ClearHotkey(hstring const& id);
+        void ClearHotkeys();
+        void SetProcessCommand(ProcessCommand processCommand);
+
+        static LRESULT CALLBACK LowLevelKeyboardProc(int nCode, WPARAM wParam, LPARAM lParam);
+
+    private:
+        LRESULT CALLBACK DoLowLevelKeyboardProc(int nCode, WPARAM wParam, LPARAM lParam);
+
+        static inline KeyboardListener* s_instance;
+        HHOOK s_llKeyboardHook = nullptr;
+
+        // Max DWORD for key code to disable keys.
+        const DWORD VK_DISABLED = 0x100;
+        DWORD vkCodePressed = VK_DISABLED;
+
+        std::multiset<HotkeyDescriptor> hotkeyDescriptors;
+        std::mutex mutex;
+
+        std::function<void(hstring const&)> m_processCommandCb;
+    };
+}
+
+namespace winrt::CmdPalKeyboardService::factory_implementation
+{
+    struct KeyboardListener : KeyboardListenerT<KeyboardListener, implementation::KeyboardListener>
+    {
+    };
+}

src/modules/cmdpal/CmdPalKeyboardService/KeyboardListener.idl

@@ -0,0 +1,16 @@
+
+namespace CmdPalKeyboardService
+{
+    [version(1.0), uuid(78ab07cd-e128-4e73-86aa-e48e6b6d01ff)] delegate void ProcessCommand(String id);
+
+    [default_interface] runtimeclass KeyboardListener {
+        KeyboardListener();
+        void Start();
+        void Stop();
+
+        void SetHotkeyAction(Boolean win, Boolean ctrl, Boolean shift, Boolean alt, UInt8 key, String id);
+        void ClearHotkey(String id);
+        void ClearHotkeys();
+        void SetProcessCommand(ProcessCommand processCommand);
+    }
+}

src/modules/cmdpal/CmdPalKeyboardService/PropertySheet.props

@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project ToolsVersion="4.0"
+  xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <ImportGroup Label="PropertySheets" />
+  <PropertyGroup Label="UserMacros" />
+  <!--
+    To customize common C++/WinRT project properties: 
+    * right-click the project node
+    * expand the Common Properties item
+    * select the C++/WinRT property page
+
+    For more advanced scenarios, and complete documentation, please see:
+    https://github.com/Microsoft/cppwinrt/tree/master/nuget 
+    -->
+  <PropertyGroup />
+  <ItemDefinitionGroup />
+</Project>

src/modules/cmdpal/CmdPalKeyboardService/packages.config

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<packages>
+  <package id="Microsoft.Windows.CppWinRT" version="2.0.240111.5" targetFramework="native" />
+</packages>

src/modules/cmdpal/CmdPalKeyboardService/pch.cpp

@@ -0,0 +1 @@
+#include "pch.h"

src/modules/cmdpal/CmdPalKeyboardService/pch.h

@@ -0,0 +1,4 @@
+#pragma once
+#include <Unknwn.h>
+#include <winrt/Windows.Foundation.h>
+#include <winrt/Windows.Foundation.Collections.h>

src/modules/cmdpal/CmdPalKeyboardService/resource.h

@@ -0,0 +1,13 @@
+//{{NO_DEPENDENCIES}}
+// Microsoft Visual C++ generated include file.
+// Used by PowerToys.MeasureToolCore.rc
+
+//////////////////////////////
+// Non-localizable
+
+#define FILE_DESCRIPTION "CmdPalKeyboardService"
+#define INTERNAL_NAME "CmdPalKeyboardService"
+#define ORIGINAL_FILENAME "CmdPalKeyboardService.dll"
+
+// Non-localizable
+//////////////////////////////