terminal/src/cascadia/WindowsTerminal/main.cpp

// Copyright (c) Microsoft Corporation.
// Licensed under the MIT license.

#include "pch.h"
#include "AppHost.h"
#include "resource.h"
#include "../types/inc/User32Utils.hpp"
#include <WilErrorReporting.h>

using namespace winrt;
using namespace winrt::Windows::UI;
using namespace winrt::Windows::UI::Composition;
using namespace winrt::Windows::UI::Xaml::Hosting;
using namespace winrt::Windows::Foundation::Numerics;

// Note: Generate GUID using TlgGuid.exe tool - seriously, it won't work if you
// just generate an arbitrary GUID
TRACELOGGING_DEFINE_PROVIDER(
    g_hWindowsTerminalProvider,
    "Microsoft.Windows.Terminal.Win32Host",
    // {56c06166-2e2e-5f4d-7ff3-74f4b78c87d6}
    (0x56c06166, 0x2e2e, 0x5f4d, 0x7f, 0xf3, 0x74, 0xf4, 0xb7, 0x8c, 0x87, 0xd6),
    TraceLoggingOptionMicrosoftTelemetry());

// Routine Description:
// - Takes an image architecture and locates a string resource that maps to that architecture.
// Arguments:
// - imageArchitecture - An IMAGE_FILE_MACHINE architecture enum value
//                     - See https://docs.microsoft.com/en-us/windows/win32/sysinfo/image-file-machine-constants
// Return Value:
// - A string value representing the human-readable name of this architecture.
static std::wstring ImageArchitectureToString(USHORT imageArchitecture)
{
    // clang-format off
    const auto id = imageArchitecture == IMAGE_FILE_MACHINE_I386 ? IDS_X86_ARCHITECTURE :
                    imageArchitecture == IMAGE_FILE_MACHINE_AMD64 ? IDS_AMD64_ARCHITECTURE :
                    imageArchitecture == IMAGE_FILE_MACHINE_ARM64 ? IDS_ARM64_ARCHITECTURE :
                    imageArchitecture == IMAGE_FILE_MACHINE_ARM ? IDS_ARM_ARCHITECTURE :
                    IDS_UNKNOWN_ARCHITECTURE;
    // clang-format on

    return GetStringResource(id);
}

// Routine Description:
// - Blocks the user from launching the application with a message box dialog and early exit
//   if the process architecture doesn't match the system platform native architecture.
// - This is because the conhost.exe must match the condrv.sys on the system and the PTY
//   infrastructure that powers everything won't work if we have a mismatch.
// Arguments:
// - <none>
// Return Value:
// - <none>
static void EnsureNativeArchitecture()
{
    USHORT processMachine{};
    USHORT nativeMachine{};
    THROW_IF_WIN32_BOOL_FALSE(IsWow64Process2(GetCurrentProcess(), &processMachine, &nativeMachine));
    if (processMachine != IMAGE_FILE_MACHINE_UNKNOWN && processMachine != nativeMachine)
    {
        const auto formatPattern = GetStringResource(IDS_ERROR_ARCHITECTURE_FORMAT);

        const auto nativeArchitecture = ImageArchitectureToString(nativeMachine);
        const auto processArchitecture = ImageArchitectureToString(processMachine);

        auto buffer{ wil::str_printf<std::wstring>(formatPattern.data(), nativeArchitecture.data(), processArchitecture.data()) };

        MessageBoxW(nullptr,
                    buffer.data(),
                    GetStringResource(IDS_ERROR_DIALOG_TITLE).data(),
                    MB_OK | MB_ICONERROR);

        ExitProcess(0);
    }
}

static bool _messageIsF7Keypress(const MSG& message)
{
    return (message.message == WM_KEYDOWN || message.message == WM_SYSKEYDOWN) && message.wParam == VK_F7;
}
static bool _messageIsAltKeyup(const MSG& message)
{
    return (message.message == WM_KEYUP || message.message == WM_SYSKEYUP) && message.wParam == VK_MENU;
}
static bool _messageIsAltSpaceKeypress(const MSG& message)
{
    return message.message == WM_SYSKEYDOWN && message.wParam == VK_SPACE;
}

int __stdcall wWinMain(HINSTANCE, HINSTANCE, LPWSTR, int)
{
    TraceLoggingRegister(g_hWindowsTerminalProvider);
    TraceLoggingWrite(
        g_hWindowsTerminalProvider,
        "ExecutableStarted",
        TraceLoggingDescription("Event emitted immediately on startup"),
        TraceLoggingKeyword(MICROSOFT_KEYWORD_MEASURES),
        TelemetryPrivacyDataTag(PDT_ProductAndServicePerformance));
    ::Microsoft::Console::ErrorReporting::EnableFallbackFailureReporting(g_hWindowsTerminalProvider);

    // If Terminal is spawned by a shortcut that requests that it run in a new process group
    // while attached to a console session, that request is nonsense. That request will, however,
    // cause WT to start with Ctrl-C disabled. This wouldn't matter, because it's a Windows-subsystem
    // application. Unfortunately, that state is heritable. In short, if you start WT using cmd in
    // a weird way, ^C stops working _inside_ the terminal. Mad.
    SetConsoleCtrlHandler(NULL, FALSE);

    // Block the user from starting if they launched the incorrect architecture version of the project.
    // This should only be applicable to developer versions. The package installation process
    // should choose and install the correct one from the bundle.
    EnsureNativeArchitecture();

    // Make sure to call this so we get WM_POINTER messages.
    EnableMouseInPointer(true);

    // !!! LOAD BEARING !!!
    // We must initialize the main thread as a single-threaded apartment before
    // constructing any Xaml objects. Failing to do so will cause some issues
    // in accessibility somewhere down the line when a UIAutomation object will
    // be queried on the wrong thread at the wrong time.
    // We used to initialize as STA only _after_ initializing the application
    // host, which loaded the settings. The settings needed to be loaded in MTA
    // because we were using the Windows.Storage APIs. Since we're no longer
    // doing that, we can safely init as STA before any WinRT dispatches.
    winrt::init_apartment(winrt::apartment_type::single_threaded);

    // Create the AppHost object, which will create both the window and the
    // Terminal App. This MUST BE constructed before the Xaml manager as TermApp
    // provides an implementation of Windows.UI.Xaml.Application.
    AppHost host;
    if (!host.HasWindow())
    {
        // If we were told to not have a window, exit early. Make sure to use
        // ExitProcess to die here. If you try just `return 0`, then
        // the XAML app host will crash during teardown. ExitProcess avoids
        // that.
        ExitProcess(0);
    }

    // Initialize the xaml content. This must be called AFTER the
    // WindowsXamlManager is initialized.
    host.Initialize();

    MSG message;

    while (GetMessage(&message, nullptr, 0, 0))
    {
        // GH#638 (Pressing F7 brings up both the history AND a caret browsing message)
        // The Xaml input stack doesn't allow an application to suppress the "caret browsing"
        // dialog experience triggered when you press F7. Official recommendation from the Xaml
        // team is to catch F7 before we hand it off.
        // AppLogic contains an ad-hoc implementation of event bubbling for a runtime classes
        // implementing a custom IF7Listener interface.
        // If the recipient of IF7Listener::OnF7Pressed suggests that the F7 press has, in fact,
        // been handled we can discard the message before we even translate it.
        if (_messageIsF7Keypress(message))
        {
            if (host.OnDirectKeyEvent(VK_F7, LOBYTE(HIWORD(message.lParam)), true))
            {
                // The application consumed the F7. Don't let Xaml get it.
                continue;
            }
        }

        // GH#6421 - System XAML will never send an Alt KeyUp event. So, similar
        // to how we'll steal the F7 KeyDown above, we'll steal the Alt KeyUp
        // here, and plumb it through.
        if (_messageIsAltKeyup(message))
        {
            // Let's pass <Alt> to the application
            if (host.OnDirectKeyEvent(VK_MENU, LOBYTE(HIWORD(message.lParam)), false))
            {
                // The application consumed the Alt. Don't let Xaml get it.
                continue;
            }
        }

        // GH#7125 = System XAML will show a system dialog on Alt Space. We might want to
        // explicitly prevent that - for example when an action is bound to it. So similar to
        // above, we steal the event and hand it off to the host. When the host does not process
        // it, we will still dispatch like normal.
        if (_messageIsAltSpaceKeypress(message))
        {
            if (host.OnDirectKeyEvent(VK_SPACE, LOBYTE(HIWORD(message.lParam)), true))
            {
                continue;
            }
        }

        TranslateMessage(&message);
        DispatchMessage(&message);
    }
    return 0;
}