c2puml 2025.9.14.2

Convert C/C++ code to PlantUML diagrams with advanced filtering and transformation capabilities

c2puml - C to PlantUML Converter

A Python tool for converting C/C++ source code to PlantUML diagrams. Analyzes C/C++ projects and generates comprehensive PlantUML class diagrams showing structs, enums, unions, functions, global variables, macros, typedefs, and include relationships.

Status

Reports

• 📊 Combined Coverage Report - Comprehensive coverage report with summary and detailed per-file analysis
• 📝 Test Summary - Test execution summary and statistics
• 📊 Example Diagrams - Quick view of all generated PlantUML diagrams and PNG images
• 📋 Example Source Code - Browse the example C/C++ source files used for testing and demonstration

Documentation

• 📖 Specification - Complete technical specification and architecture documentation
• 🎨 PlantUML Template - PlantUML formatting template and diagram structure rules
• ⚙️ Configuration Guide - Detailed config.json reference and examples

Releases

• 📦 Download ZIP - Download the latest release as ZIP archive
• 📦 Download TAR.GZ - Download the latest release as TAR.GZ archive

Features

• C/C++ Parsing: Comprehensive tokenization-based parsing with preprocessor handling and conditional compilation support
• Project Analysis: Analyzes entire C/C++ projects with recursive directory scanning and configurable include depth processing
• PlantUML Generation: Creates organized PlantUML diagrams with proper UML notation and relationship visualization
• Configuration System: Flexible filtering and transformation capabilities with file-specific settings
• Enhanced UML Stereotypes: Uses specific stereotypes for different typedef types (<>, <>, <
• Smart Visibility Detection: Automatically determines public/private visibility based on header file declarations

Installation

Option 1: Install as Python Package (Recommended)

git clone https://github.com/fischerjooo/c2puml.git
cd c2puml
python3 -m pip install -e .

Option 2: Use Standalone Script (No Installation Required)

If you prefer not to install the package, you can use the standalone script directly:

git clone https://github.com/fischerjooo/c2puml.git
cd c2puml
# No installation needed - just run the script directly
python3 main.py --config tests/example/config.json

Prerequisites for standalone usage:

• Python 3.7 or later
• The complete c2puml source code (including the src/ directory)

Quick Start

Basic Usage

Using Installed Package

# Full workflow: Parse → Transform → Generate diagrams
c2puml --config tests/example/config.json

# Using current directory configuration (merges all .json files)
c2puml

# Individual steps
c2puml --config tests/example/config.json parse      # Step 1: Parse only
c2puml --config tests/example/config.json transform  # Step 2: Transform only
c2puml --config tests/example/config.json generate   # Step 3: Generate only

# With verbose output for debugging
c2puml --config tests/example/config.json --verbose

# Alternative module syntax
python3 -m c2puml.main --config tests/example/config.json

Using Standalone Script (No Installation)

# Full workflow: Parse → Transform → Generate diagrams
python3 main.py --config tests/example/config.json

# Using current directory configuration (merges all .json files)
python3 main.py

# Individual steps
python3 main.py --config tests/example/config.json parse      # Step 1: Parse only
python3 main.py --config tests/example/config.json transform  # Step 2: Transform only
python3 main.py --config tests/example/config.json generate   # Step 3: Generate only

# With verbose output for debugging
python3 main.py --config tests/example/config.json --verbose

Note: Both methods provide identical functionality. Choose the one that best fits your workflow.

Generate PNG Images

# Linux/macOS
./picgen.sh

# Windows
picgen.bat

The scripts automatically:

• Download PlantUML.jar if needed
• Install Graphviz (required for PNG generation)
• Test the setup before conversion
• Convert all .puml files to PNG images

Note: The script automatically handles Graphviz installation and testing to resolve the "Dot executable does not exist" error.

Configuration

Create a config.json to customize analysis and output. Minimal example:

{
  "project_name": "my_project",
  "source_folders": ["./src"],
  "output_dir": "./output"
}

Run with a config file:

c2puml --config config.json
# or (merges all .json files in the current directory)
c2puml

For full examples (file-specific include filters, include depth, formatting, and the transformation system), see the Configuration Guide: docs/configuration.md.

Generated Output

The tool creates PlantUML diagrams showing:

• Source files with functions, structs, enums, unions
• Header files with declarations
• Include relationships between files
• Typedef relationships with enhanced UML stereotypes
• Color-coded elements (source, headers, typedefs)
• Dynamic visibility detection (public/private based on header presence)

Troubleshooting

Common Issues

"Command 'c2puml' not found"

• Solution: Install the package with pip install -e .
• Alternative: Use the standalone script: python3 main.py --config config.json

"Module 'c2puml' not found"

• Solution: Ensure you're in the project root directory and the src/ folder exists
• Alternative: Use the standalone script which handles path setup automatically

"Permission denied" errors

• Solution: Use the standalone script which doesn't require installation: python3 main.py

"Dot executable does not exist" (PlantUML PNG generation)

• Solution: Install Graphviz or use the provided scripts: ./scripts/picgen.sh or scripts/picgen.bat

Getting Help

• Quick Test: Try the standalone script first: python3 main.py --config tests/example/config.json
• Development: Use the debug script: python scripts/debug.py
• Examples: Run the example workflow: ./scripts/run_example.sh or scripts/run_example.bat

License

MIT License