🛠️ Monorepo Development & Quality Infrastructure

This repository manages two distinct FreeRTOS firmware projects with a shared, high-integrity tooling infrastructure.

📂 Repository Architecture

Component	Path	Description
C Project	03_FreeRTOS/	Legacy C implementation using MISRA C:2012.
C++ Project	04_FreeRTOS_Cpp/	Modern C++ implementation using Native C++ Static Analysis.
Tooling Hub	build_utils/	Centralized Linter rules, Suppressions, and Pre-commit configs.
VS Code Config	.vscode/	Shared Build Tasks and Cortex-Debug profiles.

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🚀 Build & Debug Environment

We use VS Code as a unified IDE for both projects. Build tasks are context-aware using the cwd (Current Working Directory) attribute.

VS Code Tasks (tasks.json)

• Build 03_FreeRTOS: Executes make within the C project root.
• CMake Build 04_FreeRTOS_Cpp: Handles CMake generation and parallel build (make -j) for the C++ project.
• Run Quality Gate: Triggers the local pre-commit suite against all files.

Debugging (launch.json)

• Cortex-Debug: Separate profiles for each project point to their respective .elf artifacts.
• GDB Path: Explicitly mapped to /usr/bin/gdb-multiarch for WSL2 compatibility.

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🛡️ Quality Gate & Static Analysis

To prevent “Rule Friction” between C and C++ standards, the analysis pipeline is split into parallel hooks.

1. Cppcheck (Split Strategy)

• C Hook: Applies strict MISRA C:2012 headlines.
• C++ Hook: Utilizes the Native Cppcheck Engine (--enable=all) with --std=c++17. This resolves false positives related to C++ Initializer Lists (Rule 12.3) and Namespace usage.
• Suppressions: Managed via build_utils/cppcheck_suppressions.txt to handle FreeRTOS task entry points and HAL callbacks.

2. Code Metrics (Lizard)

• Enforces a Cyclomatic Complexity (CCN) < 10 across both projects.
• Limits function length to 15 lines to ensure maintainable C++ class methods.

3. Git Hooks (Pre-commit)

The hooks are force-linked to our subfolder configuration to ensure every commit is audited:

pre-commit install --config build_utils/.pre-commit-config.yaml --overwrite

📈 Scaling the Monorepo

To add a new firmware project to this ecosystem:

1. Create Folder: Use the XX_ProjectName convention.

2. Update Matrix: Add the folder name to .github/workflows/ci_quality.yml. Matrix Update: Simply add the new folder name to the project_path list in ci_quality.yml:

    strategy:
    matrix:
        project_path: ["03_FreeRTOS", "04_FreeRTOS_Cpp", "05_NewProject"]
   

   Logic: The existing if/else bash logic will handle it automatically, applying C or C++ rules based on your folder naming convention.

3. Register Hook: Add a project-specific Cppcheck hook in build_utils/.pre-commit-config.yaml.
   1. Cppcheck: Add a new hook entry in .pre-commit-config.yaml. Set files: ^05_NewProject/App/. Add the new -I include paths to the args section.
   2. Lizard: Update the regex in the Lizard hook to include the new folder: ^(03|04|05)_Project/App/.
4. CWD Mapping: Add a new build task and launch profile in .vscode/ using the cwd parameter.
   1. Tasks: Duplicate an existing build task in tasks.json and update the label and cwd (path) to the new folder.
   2. Debug: Add a new configuration to launch.json pointing to the new project’s .elf file.