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// This file is part of the uutils coreutils package.
//
// For the full copyright and license information, please view the LICENSE
// file that was distributed with this source code.
use rand::Rng;
use std::ffi::OsString;
use uufuzz::{generate_and_run_uumain, generate_random_string, run_gnu_cmd};
// Mock echo implementation with some bugs for demonstration
fn mock_buggy_echo_main(args: std::vec::IntoIter<OsString>) -> i32 {
let args: Vec<OsString> = args.collect();
let mut should_add_newline = true;
let mut enable_escapes = false;
let mut start_index = 1;
// Parse arguments (simplified)
for arg in args.iter().skip(1) {
let arg_str = arg.to_string_lossy();
if arg_str == "-n" {
should_add_newline = false;
start_index += 1;
} else if arg_str == "-e" {
enable_escapes = true;
start_index += 1;
} else {
break;
}
}
// Print arguments
for (i, arg) in args.iter().skip(start_index).enumerate() {
if i > 0 {
print!(" ");
}
let arg_str = arg.to_string_lossy();
if enable_escapes {
// Simulate a bug: incomplete escape sequence handling
let processed = arg_str.replace("\\n", "\n").replace("\\t", "\t");
print!("{}", processed);
} else {
print!("{}", arg_str);
}
}
if should_add_newline {
println!();
}
0
}
// Generate test arguments for echo command
fn generate_echo_args() -> Vec<OsString> {
let mut rng = rand::rng();
let mut args = vec![OsString::from("echo")];
// Randomly add flags
if rng.random_bool(0.3) {
// 30% chance
args.push(OsString::from("-n"));
}
if rng.random_bool(0.2) {
// 20% chance
args.push(OsString::from("-e"));
}
// Add 1-3 random string arguments
let num_args = rng.random_range(1..=3);
for _ in 0..num_args {
let arg = generate_random_string(rng.random_range(1..=15));
args.push(OsString::from(arg));
}
args
}
fn main() {
println!("=== Fuzzing Simulation uufuzz Example ===");
println!("This simulates how libFuzzer would test our echo implementation");
println!("against GNU echo with random inputs.\n");
let num_tests = 10;
let mut passed = 0;
let mut failed = 0;
for i in 1..=num_tests {
println!("--- Fuzz Test {} ---", i);
let args = generate_echo_args();
println!(
"Testing with args: {:?}",
args.iter().map(|s| s.to_string_lossy()).collect::<Vec<_>>()
);
// Run our implementation
let rust_result = generate_and_run_uumain(&args, mock_buggy_echo_main, None);
// Run GNU implementation
match run_gnu_cmd("echo", &args[1..], false, None) {
Ok(gnu_result) => {
// Check if results match
let stdout_match = rust_result.stdout.trim() == gnu_result.stdout.trim();
let exit_code_match = rust_result.exit_code == gnu_result.exit_code;
if stdout_match && exit_code_match {
println!("✓ PASS: Implementations match");
passed += 1;
} else {
println!("✗ FAIL: Implementations differ");
failed += 1;
// Show the difference in a controlled way (not panicking like compare_result)
if !stdout_match {
println!(" Stdout difference:");
println!(
" Ours: '{}'",
rust_result.stdout.trim().replace('\n', "\\n")
);
println!(
" GNU: '{}'",
gnu_result.stdout.trim().replace('\n', "\\n")
);
}
if !exit_code_match {
println!(
" Exit code difference: {} vs {}",
rust_result.exit_code, gnu_result.exit_code
);
}
}
}
Err(error_result) => {
println!("⚠ GNU echo not available: {}", error_result.stderr);
println!(" Our result: '{}'", rust_result.stdout.trim());
// Don't count this as pass or fail
continue;
}
}
println!();
}
println!("=== Fuzzing Results ===");
println!("Total tests: {}", num_tests);
println!("Passed: {}", passed);
println!("Failed: {}", failed);
if failed > 0 {
println!(
"\n⚠ Found {} discrepancies! In real fuzzing, these would be investigated.",
failed
);
println!("This demonstrates how differential fuzzing can find bugs in implementations.");
} else {
println!("\n✓ All tests passed! The implementations appear compatible.");
}
println!("\nIn a real libfuzzer setup, this would run thousands of iterations");
println!("automatically with more sophisticated input generation.");
}
|
