Code shared from the Rust Playground

playground.rs

use sha2::{Sha256, Digest};

/// A macro that takes a file path string literal, hashes the embedded bytes 
/// using SHA-256, and returns a hex-encoded String.
macro_rules! get_file_hash {
    ($file_path:expr) => {{
        let bytes = include_bytes!($file_path);
        let mut hasher = Sha256::new();
        hasher.update(bytes);
        let result = hasher.finalize();
        
        // Convert the GenericArray to a hex string
        result.iter()
              .map(|b| format!("{:02x}", b))
              .collect::<String>()
    }};
}

fn main() {
    // We can now assign the result of the macro to a variable
    let self_hash = get_file_hash!("main.rs");

    println!("--- [Self-Audit Report] ---");
    println!("Target: main.rs");
    println!("SHA-256 Hash: {}", self_hash);
    
    // Example of using the hash in logic
    if self_hash.starts_with("e3b0") {
        println!("Warning: This hash represents an empty file.");
    } else {
        println!("Status: Integrity Verified.");
    }
}