c-to-ast

C to AST Skill

Purpose

This Skill converts C source code into its Abstract Syntax Tree (AST) representation.

Use this Skill when you need to:

• Understand the structure of a C program
• Analyze functions, statements, and expressions
• Prepare C code for static analysis or security analysis
• Transform C code into an intermediate representation (AST)
• Feed structured code information into downstream tools or agents

The AST is generated using a Python-based C parser and printed directly to standard output.

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When to Use

Apply this Skill when the user asks to:

• “Parse this C code”
• “Convert this C file to an AST”
• “Show me the AST of this C program”
• “Analyze the structure of this C code”
• “Extract syntax tree / abstract syntax tree from C”

This Skill is especially useful in compiler frontends, program analysis, and security research workflows.

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Instructions

Follow these steps strictly and in order:

1. Navigate to the Skill scripts directory

   • Change working directory to the scripts/ directory under this skill:

     scripts/
     

2. Handle the input C source

   • If the user provides a path to a .c file, use it directly.
   • If the user provides inline C code as a string, you must first save it to a C source file using the provided script:

     python3 save_c.py --input "<C code string>" --output <output_dir> --filename <filename>.c
     

   • Ensure the generated file has a .c extension and is successfully written to disk.

3. Run the AST extraction script

   • Convert the C source file to its Abstract Syntax Tree by executing:

     python3 c_2_ast.py --input <path_to_c_file>
     

4. Do not modify the source code

   • This Skill is strictly read-only.
   • Do not rewrite, reformat, optimize, or otherwise alter the C code.

5. Return the AST output verbatim

   • The script prints the AST directly to standard output.
   • Return the output exactly as produced.
   • Do not summarize, paraphrase, or restructure the AST.
   • Preserve indentation, hierarchy, and node ordering.