refactor: modernize core library and migrate to CMake/LLVM

.github/workflows/release.yml

@@ -0,0 +1,70 @@
+name: Build and Release
+
+on:
+  push:
+    tags:
+      - 'v*'
+  pull_request:
+    branches:
+      - main
+
+jobs:
+  build:
+    runs-on: windows-latest
+    permissions:
+      contents: write
+      id-token: write
+      attestations: write
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v6
+
+      - name: Setup MSYS2
+        uses: msys2/setup-msys2@v2
+        with:
+          msystem: UCRT64
+          update: true
+          install: >-
+            mingw-w64-ucrt-x86_64-clang
+            mingw-w64-ucrt-x86_64-cmake
+            mingw-w64-ucrt-x86_64-ninja
+
+      - name: Build with LLVM/Clang
+        shell: msys2 {0}
+        run: |
+          cmake -S . -B build -G Ninja \
+            -DCMAKE_C_COMPILER=clang \
+            -DCMAKE_BUILD_TYPE=MinSizeRel
+          cmake --build build
+
+      - name: Attest Build Provenance
+        if: startsWith(github.ref, 'refs/tags/v')
+        uses: actions/attest@v4
+        with:
+          subject-path: build/umpdc.dll
+
+      - name: Upload Artifact
+        uses: actions/upload-artifact@v7
+        with:
+          name: umpdc-dll
+          path: build/umpdc.dll
+
+  release:
+    needs: build
+    if: startsWith(github.ref, 'refs/tags/v')
+    runs-on: ubuntu-latest
+    permissions:
+      contents: write
+    steps:
+      - name: Download Artifact
+        uses: actions/download-artifact@v8
+        with:
+          name: umpdc-dll
+
+      - name: Create Release
+        uses: softprops/action-gh-release@v3
+        with:
+          files: umpdc.dll
+          generate_release_notes: true
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

CMakeLists.txt

@@ -0,0 +1,35 @@
+cmake_minimum_required(VERSION 3.10)
+project(NoSteamWebHelper C)
+
+add_library(umpdc SHARED src/Library.c)
+
+# Extreme size optimization & no stdlib
+if(CMAKE_C_COMPILER_ID MATCHES "GNU|Clang")
+    target_compile_options(umpdc PRIVATE 
+        -Oz 
+        -municode 
+        -fno-stack-protector
+        -fno-ident
+        -fno-asynchronous-unwind-tables
+        -ffunction-sections 
+        -fdata-sections
+    )
+    target_link_options(umpdc PRIVATE 
+        -nostdlib
+        -Wl,--gc-sections
+        -Wl,--exclude-all-symbols
+        -Wl,--no-insert-timestamp
+        -s
+    )
+    target_link_libraries(umpdc PRIVATE ntdll kernel32 user32 advapi32 shell32)
+elseif(MSVC)
+    target_compile_options(umpdc PRIVATE /O1 /GS- /Zl)
+    target_link_options(umpdc PRIVATE 
+        /NODEFAULTLIB 
+        /ENTRY:DllMainCRTStartup
+        /OPT:REF
+        /OPT:ICF
+        /MERGE:.rdata=.text
+    )
+    target_link_libraries(umpdc PRIVATE ntdll.lib kernel32.lib user32.lib advapi32.lib shell32.lib)
+endif()

GEMINI.md

@@ -0,0 +1,46 @@
+# NoSteamWebHelper - Instructions & Context
+
+## Project Overview
+NoSteamWebHelper is a high-performance Win32 utility (C-based) that dynamically disables Steam's Chromium Embedded Framework (CEF) / WebHelper when a game is running. It aims to replace the removed `-no-browser` flag, freeing system resources while keeping Steam functional.
+
+### Architecture
+- **Language**: Pure C (Win32 API), optimized for binary size (`nostdlib`).
+- **Core Component**: `umpdc.dll`, designed to be loaded via DLL side-loading/injection (placed next to `steam.exe`).
+- **Mechanics**:
+  - **Event Hooking**: Uses `SetWinEventHook` to detect Steam window creations.
+  - **Registry Monitoring**: Asynchronously monitors `HKCU\SOFTWARE\Valve\Steam\RunningAppID` to detect game state changes.
+  - **Process Management**: Uses `Toolhelp32` snapshotting to identify and terminate `steamwebhelper.exe` processes spawned by Steam.
+  - **Thread Safety**: Employs `Interlocked` atomic operations for race-condition-free initialization of the monitoring thread.
+  - **UI**: Provides a minimalist system tray icon for manual toggling and status feedback.
+
+## Building and Pipeline
+The project uses a modern CMake-based build system optimized for size and performance.
+
+### Build Requirements
+- **MSYS2** (UCRT64 environment)
+- **LLVM/Clang** (preferred) or GCC
+- **CMake** & **Ninja**
+
+### Compilation Commands
+```bash
+# Configuration for maximum size optimization
+cmake -S . -B build -G Ninja -DCMAKE_C_COMPILER=clang -DCMAKE_BUILD_TYPE=MinSizeRel
+
+# Build
+cmake --build build
+```
+Output binary: `build/umpdc.dll`
+
+### CI/CD Pipeline
+- **Platform**: GitHub Actions (`.github/workflows/release.yml`)
+- **Features**:
+  - **Validation**: Compiles the project on every Pull Request to `main`.
+  - **Deployment**: On version tags (`v*`), performs a production build using **LLVM/Clang 22**.
+  - **Immutability & Trust**: Generates **GitHub Artifact Attestations** (SLSA) for every release, ensuring cryptographic proof of provenance.
+
+## Development Conventions
+- **Minimalism**: Avoid C Standard Library (`nostdlib`). Use direct Win32/NT APIs.
+- **Size Optimization**: Use aggressive compiler flags (`-Oz`, `-fno-stack-protector`, `-fno-asynchronous-unwind-tables`).
+- **Nomenclature**: Use descriptive constants (defined in `Library.c`) instead of magic strings or numbers.
+- **Safety**: Always close Handles and use atomic operations when managing shared state between the Main thread and the Registry Monitor thread.
+- **Provenance**: All production binaries must be built through the CI pipeline to maintain "Immutable" status.

README.md

@@ -1,51 +1,46 @@
-> [!CAUTION]
-> This project is now deprecated.
-
 # NoSteamWebHelper
- A program that disables Steam's CEF/Chromium Embedded Framework.
+A high-performance utility that disables Steam's CEF (Chromium Embedded Framework) / Steam WebHelper while gaming.
 
 ## Aim
-This program was created with the intent of replacing of Steam's command-line parameter `-no-browser` which was [removed.](https://steamcommunity.com/groups/SteamClientBeta/discussions/3/3710433479207750727/?ctp=42)
-
-
-## How does NoSteamWebHelper kill or disable the CEF/Chromium Embedded Framework? 
-
-The dynamic link library toggles the CEF depending if an is app running or not.
-
-- If an app is running then the CEF is disabled.
-
-- If an app is not running then the CEF is enabled.
-
-This way, Steam is still accessible to use.
-
-# Usage
+This program replaces Steam's removed `-no-browser` command-line parameter. It dynamically toggles the Steam WebHelper based on your activity to free up system resources without losing access to your library.
+
+- **Game running**: Steam WebHelper is disabled (processes terminated and suppressed).
+- **No game running**: Steam WebHelper is enabled (interface restored).
+
+## Key Features & Refactoring (2026)
+This project has been fully refactored for maximum performance and reliability:
+- **Ultra-Lightweight**: Written in pure C with `nostdlib`. The resulting `umpdc.dll` is only a few KB.
+- **Modern Build System**: Migrated to **CMake** with support for **LLVM/Clang 22** for state-of-the-art optimizations.
+- **Zero-Leak Architecture**: 
+  - Uses `Interlocked` atomic operations for thread-safe monitor initialization.
+  - Replaced `wtsapi32` dependency with `Toolhelp32` for better compatibility and smaller footprint.
+  - Asynchronous registry monitoring using Win32 Events to prevent UI/Hook freezes.
+- **Immutable Releases**: Automated CI/CD pipeline via GitHub Actions with cryptographic build provenance (SLSA).
+
+## Usage
 1. Download the latest release from [GitHub Releases](https://github.com/Aetopia/NoSteamWebHelper/releases).
-
-2. Place `umpdc.dll` in your Steam installation directory where `steam.exe` is located.
-
-3. Make sure Steam is fully closed and launch a new instance of Steam.
-
-4. Start up an app and the CEF will be toggled accordingly.
-
-> [!NOTE]
-> - You may also manually toggle the CEF via a tray icon.
-> - To prevent the CEF from automatically showing when restored, pass `-silent` to Steam.
-
-## Build
-1. Install & update [MSYS2](https://www.msys2.org):
-
-    ```bash
-    pacman -Syu --noconfirm
-    ```
-
-3. Install [GCC](https://gcc.gnu.org) & [MinHook](https://github.com/TsudaKageyu/minhook):
-
-    ```bash
-    pacman -Syu mingw-w64-ucrt-x86_64-gcc --noconfirm
-    ```
-
-
-3. Start MSYS2's `UCRT64` environment & run `Build.cmd`.
-
-
-
+2. Place `umpdc.dll` in your Steam installation directory (same folder as `steam.exe`).
+3. Ensure Steam is fully closed, then launch Steam.
+4. The CEF will now toggle automatically when you launch/close a game.
+
+> [!TIP]
+> - You can manually toggle the state via the tray icon.
+> - Launch Steam with `-silent` to prevent the CEF from popping up unexpectedly when restored.
+
+## Build from Source
+The project uses **MSYS2** with the **UCRT64** environment.
+
+1. **Install Prerequisites**:
+   ```bash
+   pacman -Syu mingw-w64-ucrt-x86_64-clang mingw-w64-ucrt-x86_64-cmake mingw-w64-ucrt-x86_64-ninja
+   ```
+
+2. **Compile**:
+   ```bash
+   cmake -S . -B build -G Ninja -DCMAKE_C_COMPILER=clang -DCMAKE_BUILD_TYPE=MinSizeRel
+   cmake --build build
+   ```
+   The optimized `umpdc.dll` will be located in the `build/` directory.
+
+## CI/CD
+This project uses GitHub Actions for automated builds. Every tagged release (`v*`) triggers a Clang-optimized build and generates a **Verified Provenance Attestation**, ensuring the binary's integrity.