MetahookInstaller

Windows installer and plugin list editor for MetaHookSv, built with Avalonia and ReactiveUI on .NET 10.

Features

• Discover supported Steam games and select custom GoldSrc game directories.
• Install or uninstall MetaHook runtime files from a supplied install/output/ directory.
• Install or uninstall from the command line with MetahookInstallerCLI.exe.
• Enable, disable and reorder plugins in metahook/configs/plugins.lst.
• Switch between English and Simplified Chinese, and System, Light and Dark themes.

Projects

• src/MetahookInstallerCore: shared installation library (payload copying, Steam lookup, uninstall, shortcuts).
• src/MetahookInstallerCLI: command line wrapper.
• src/MetahookInstallerAvalonia: Avalonia UI and resources.
• src/MetahookInstallerAvalonia.Desktop: Windows x64 desktop entry point.

The source was imported from toolsrc/MetahookInstaller in MetaHookSv. The original project remains in that repository.

Run a Release

Download MetahookInstaller-windows-x64.7z from this repository's releases and extract it. The installer is self-contained; installing the .NET runtime is not required.

The standalone installer archive contains the installer and its runtime dependencies. Obtain a MetaHookSv release separately and place its complete install/output/ tree next to MetahookInstaller.exe. The MetaHookSv aggregate archive already supplies this layout:

MetahookInstaller-Output/
  MetahookInstaller.exe
  MetahookInstallerCLI.exe
  README.md
  LICENSE
  ...other installer runtime files...
  install/
    output/
      MetaHook.exe and/or MetaHook_blob.exe
      svencoop/
      ...other MetaHook release files...

Start the installer:

Set-Location path\to\MetahookInstaller-Output
.\MetahookInstaller.exe

Select a game, or specify a custom game root and mod directory, then click Install. The Editor tab manages an installed game's plugin list.

Steam installations of Zombie Panic! (App ID 3825360, mod directory zp) are discovered automatically and appear in the game selector.

Release builds resolve install/output/ from the executable's directory, independently of the working directory. Debug builds also search its ancestors. Language (lang), theme (theme) and generated launch shortcuts are stored in the current working directory.

The installer maps common svencoop/ resources to the selected mod, selects the normal or blob launcher, and installs root runtime DLLs such as libcurl and Steam API. SDL2/SDL3 are replaced only for normal engines that import SDL2. Existing user plugin lists are retained; root tools and debug symbols are not copied to the game.

Installation overwrites matching root runtime DLLs. Uninstall removes MetaHook launcher and mod files; root DLLs remain in the game directory, and original DLL versions are not restored automatically.

CLI Usage

MetahookInstallerCLI.exe performs the same installation and uninstallation as the GUI. Like the GUI, it resolves install/output/ from its own directory and writes the launch shortcut to the current working directory.

# Install into the Steam copy of Sven Co-op
.\MetahookInstallerCLI.exe -appid 225840
# Install into the Steam copy of Zombie Panic! (defaults to mod directory zp)
.\MetahookInstallerCLI.exe -appid 3825360
# Query Zombie Panic! without installing or requiring a payload
.\MetahookInstallerCLI.exe -appid 3825360 -describe-target
# Install into a mod of a specific Half-Life directory
.\MetahookInstallerCLI.exe -appid 70 -gamedir "D:\Games\Half-Life" -moddir gearbox
# Uninstall
.\MetahookInstallerCLI.exe -appid 225840 -uninstall

Arguments (case-insensitive):

• -appid <appid>: required Steam app ID of the game.
• -gamedir <gamedir>: optional game root directory. Defaults to the app's Steam install directory.
• -moddir <moddir>: optional mod directory under the game root. Defaults to the app's base mod in the supported games list, for example svencoop for 225840, valve for 70 and zp for 3825360; required for other app IDs.
• -uninstall: remove MetaHook instead of installing it.
• -describe-target: validate and describe the game without requiring a payload, copying files or creating a shortcut. Prints one JSON object with GameDirectory (absolute path), ModDirectory and LauncherPath. Assumes a complete payload containing both launchers; ordinary installation still falls back to the blob launcher when the normal payload launcher is absent.
• -include-debug-symbols: also copy root .pdb files when installing, retaining their names even when MetaHook.exe is renamed to svencoop.exe. Normal installations continue to omit root symbols.
• -help: print usage.
• -plugins-only: deploy a standalone plugin payload into an existing MetaHook installation. Accepts -describe-target to validate/query that installation, or -include-debug-symbols when installing. Cannot be combined with -uninstall.

Plugin-only payloads require install/output/svencoop/metahook/plugins/*.dll, but no launcher. The existing launcher and <moddir>/metahook/ must exist. Common resources are mapped to the selected mod as in a full install, including plugin PDBs and dependency libraries under the mod directory. Root executables, DLLs and PDBs are never copied; plugin lists and their templates are neither overwritten, created nor deleted. No shortcut is created. Install MetaHook and enable the plugin in plugins.lst first; this mode does not install missing runtime dependencies or enable plugins automatically.

.\MetahookInstallerCLI.exe -appid 225840 -plugins-only -describe-target
.\MetahookInstallerCLI.exe -appid 225840 -plugins-only -include-debug-symbols

-uninstall, -describe-target and -include-debug-symbols are mutually exclusive. Query errors go to stderr and return exit code 1. Omitting -gamedir also enables Steam discovery in query mode:

.\MetahookInstallerCLI.exe -appid 225840 -describe-target
.\MetahookInstallerCLI.exe -appid 70 -gamedir "D:\Games\Half-Life" -include-debug-symbols

The MetaHookSv aggregator's opt-in LaunchGame project builds this CLI automatically, queries the debugger path at CMake configuration time, and deploys a freshly staged payload plus symbols before F5 launches the game. Game files are only modified by the deployment build, not by the configure-time query.

Both installation and uninstallation require <gamedir>/<moddir>/liblist.gam, so a mistyped mod directory cannot remove the root launchers. The exit code is 0 on success and 1 on invalid arguments, errors, or files that could not be deleted during uninstallation.

Build

Use Windows x64 with the .NET 10 SDK (global.json selects the latest compatible .NET 10 feature band). NativeAOT publishing also requires the Visual Studio 2022 Desktop development with C++ workload and a Windows SDK.

From the repository root:

dotnet restore MetahookInstaller.slnx
dotnet build MetahookInstaller.slnx -c Debug --no-restore
dotnet build MetahookInstaller.slnx -c Release --no-restore
dotnet run --project src\MetahookInstallerAvalonia.Desktop
dotnet run --project src\MetahookInstallerCLI -- -appid 225840

Place a MetaHookSv install/output/ tree in the repository root, or an ancestor of the Debug executable, to exercise installation while developing.

File-system regression tests

The test harness uses .NET without additional test packages. It covers source resolution, resource mapping, launcher selection, runtime DLL copying, SDL conditions, existing plugin list preservation, uninstallation, shortcuts and CLI argument handling:

dotnet run --project tests/MetahookInstaller.FileTests -c Release
# Also install a real CMake output tree into temporary simulated game directories:
dotnet run --project tests/MetahookInstaller.FileTests -c Release -- --payload D:/MetaHookSv/install/output

Publish

The existing folder profile publishes a self-contained Windows x64 NativeAOT program:

dotnet publish src\MetahookInstallerAvalonia.Desktop\MetahookInstallerAvalonia.Desktop.csproj -p:PublishProfile=FolderProfile -o MetahookInstaller-Output
Move-Item -LiteralPath MetahookInstaller-Output\MetahookInstallerAvalonia.Desktop.exe -Destination MetahookInstaller-Output\MetahookInstaller.exe -Force
Copy-Item -LiteralPath README.md,LICENSE -Destination MetahookInstaller-Output

The current dependency versions emit trimming and AOT analysis warnings. Check the published program's behavior as well as build success.

The CLI is published as a trimmed single-file executable with bundle compression disabled and placed next to MetahookInstaller.exe:

dotnet publish src/MetahookInstallerCLI/MetahookInstallerCLI.csproj -c Release -r win-x64 --self-contained true -p:PublishSingleFile=true -p:IncludeNativeLibrariesForSelfExtract=true -p:EnableCompressionInSingleFile=false -p:PublishTrimmed=true -p:DebugType=None -p:DebugSymbols=false -o build/cli-publish
Copy-Item -LiteralPath build\cli-publish\MetahookInstallerCLI.exe -Destination MetahookInstaller-Output

MetaHookSv publishes the GUI as a trimmed single self-contained executable, including native dependencies, using the following command, and ships the CLI next to it. Native DLLs are extracted automatically at runtime:

dotnet publish src/MetahookInstallerAvalonia.Desktop/MetahookInstallerAvalonia.Desktop.csproj -c Release -r win-x64 --self-contained true -p:PublishAot=false -p:PublishTrimmed=true -p:PublishSingleFile=true -p:IncludeNativeLibrariesForSelfExtract=true -p:DebugSymbols=false -p:DebugType=None -o MetahookInstaller-Output

CI and Releases

• Pushes and pull requests to main, and manual runs, build and package Windows x64 with .NET 8 on windows-2022.
• Tags matching v* create a GitHub Release with MetahookInstaller-windows-x64.7z.
• Both workflows use the same composite action to restore, build, run the file-system tests, publish the GUI and CLI, include documentation, exclude debug symbols and verify the 7z archive.

License

MIT; see LICENSE for the original copyright notice.