Create an uufuzz crate for common functions and use it (#7954)

* uufuzz: create a crate with the common functions

* uufuzz: move the fuzz-common functions

* uufuzz: polish the crate

* adjust the fuzzer to use uufuzz

fuzz/uufuzz/src/lib.rs

@@ -0,0 +1,438 @@
+// 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 console::Style;
+use libc::STDIN_FILENO;
+use libc::{STDERR_FILENO, STDOUT_FILENO, close, dup, dup2, pipe};
+use pretty_print::{
+    print_diff, print_end_with_status, print_or_empty, print_section, print_with_style,
+};
+use rand::Rng;
+use rand::prelude::IndexedRandom;
+use std::env::temp_dir;
+use std::ffi::OsString;
+use std::fs::File;
+use std::io::{Seek, SeekFrom, Write};
+use std::os::fd::{AsRawFd, RawFd};
+use std::process::{Command, Stdio};
+use std::sync::atomic::Ordering;
+use std::sync::{Once, atomic::AtomicBool};
+use std::{io, thread};
+
+pub mod pretty_print;
+
+/// Represents the result of running a command, including its standard output,
+/// standard error, and exit code.
+pub struct CommandResult {
+    /// The standard output (stdout) of the command as a string.
+    pub stdout: String,
+
+    /// The standard error (stderr) of the command as a string.
+    pub stderr: String,
+
+    /// The exit code of the command.
+    pub exit_code: i32,
+}
+
+static CHECK_GNU: Once = Once::new();
+static IS_GNU: AtomicBool = AtomicBool::new(false);
+
+pub fn is_gnu_cmd(cmd_path: &str) -> Result<(), std::io::Error> {
+    CHECK_GNU.call_once(|| {
+        let version_output = Command::new(cmd_path).arg("--version").output().unwrap();
+
+        println!("version_output {version_output:#?}");
+
+        let version_str = String::from_utf8_lossy(&version_output.stdout).to_string();
+        if version_str.contains("GNU coreutils") {
+            IS_GNU.store(true, Ordering::Relaxed);
+        }
+    });
+
+    if IS_GNU.load(Ordering::Relaxed) {
+        Ok(())
+    } else {
+        panic!("Not the GNU implementation");
+    }
+}
+
+pub fn generate_and_run_uumain<F>(
+    args: &[OsString],
+    uumain_function: F,
+    pipe_input: Option<&str>,
+) -> CommandResult
+where
+    F: FnOnce(std::vec::IntoIter<OsString>) -> i32 + Send + 'static,
+{
+    // Duplicate the stdout and stderr file descriptors
+    let original_stdout_fd = unsafe { dup(STDOUT_FILENO) };
+    let original_stderr_fd = unsafe { dup(STDERR_FILENO) };
+    if original_stdout_fd == -1 || original_stderr_fd == -1 {
+        return CommandResult {
+            stdout: "".to_string(),
+            stderr: "Failed to duplicate STDOUT_FILENO or STDERR_FILENO".to_string(),
+            exit_code: -1,
+        };
+    }
+
+    println!("Running test {:?}", &args[0..]);
+    let mut pipe_stdout_fds = [-1; 2];
+    let mut pipe_stderr_fds = [-1; 2];
+
+    // Create pipes for stdout and stderr
+    if unsafe { pipe(pipe_stdout_fds.as_mut_ptr()) } == -1
+        || unsafe { pipe(pipe_stderr_fds.as_mut_ptr()) } == -1
+    {
+        return CommandResult {
+            stdout: "".to_string(),
+            stderr: "Failed to create pipes".to_string(),
+            exit_code: -1,
+        };
+    }
+
+    // Redirect stdout and stderr to their respective pipes
+    if unsafe { dup2(pipe_stdout_fds[1], STDOUT_FILENO) } == -1
+        || unsafe { dup2(pipe_stderr_fds[1], STDERR_FILENO) } == -1
+    {
+        unsafe {
+            close(pipe_stdout_fds[0]);
+            close(pipe_stdout_fds[1]);
+            close(pipe_stderr_fds[0]);
+            close(pipe_stderr_fds[1]);
+        }
+        return CommandResult {
+            stdout: "".to_string(),
+            stderr: "Failed to redirect STDOUT_FILENO or STDERR_FILENO".to_string(),
+            exit_code: -1,
+        };
+    }
+
+    let original_stdin_fd = if let Some(input_str) = pipe_input {
+        // we have pipe input
+        let mut input_file = tempfile::tempfile().unwrap();
+        write!(input_file, "{input_str}").unwrap();
+        input_file.seek(SeekFrom::Start(0)).unwrap();
+
+        // Redirect stdin to read from the in-memory file
+        let original_stdin_fd = unsafe { dup(STDIN_FILENO) };
+        if original_stdin_fd == -1 || unsafe { dup2(input_file.as_raw_fd(), STDIN_FILENO) } == -1 {
+            return CommandResult {
+                stdout: "".to_string(),
+                stderr: "Failed to set up stdin redirection".to_string(),
+                exit_code: -1,
+            };
+        }
+        Some(original_stdin_fd)
+    } else {
+        None
+    };
+
+    let (uumain_exit_status, captured_stdout, captured_stderr) = thread::scope(|s| {
+        let out = s.spawn(|| read_from_fd(pipe_stdout_fds[0]));
+        let err = s.spawn(|| read_from_fd(pipe_stderr_fds[0]));
+        #[allow(clippy::unnecessary_to_owned)]
+        // TODO: clippy wants us to use args.iter().cloned() ?
+        let status = uumain_function(args.to_owned().into_iter());
+        // Reset the exit code global variable in case we run another test after this one
+        // See https://github.com/uutils/coreutils/issues/5777
+        uucore::error::set_exit_code(0);
+        io::stdout().flush().unwrap();
+        io::stderr().flush().unwrap();
+        unsafe {
+            close(pipe_stdout_fds[1]);
+            close(pipe_stderr_fds[1]);
+            close(STDOUT_FILENO);
+            close(STDERR_FILENO);
+        }
+        (status, out.join().unwrap(), err.join().unwrap())
+    });
+
+    // Restore the original stdout and stderr
+    if unsafe { dup2(original_stdout_fd, STDOUT_FILENO) } == -1
+        || unsafe { dup2(original_stderr_fd, STDERR_FILENO) } == -1
+    {
+        return CommandResult {
+            stdout: "".to_string(),
+            stderr: "Failed to restore the original STDOUT_FILENO or STDERR_FILENO".to_string(),
+            exit_code: -1,
+        };
+    }
+    unsafe {
+        close(original_stdout_fd);
+        close(original_stderr_fd);
+    }
+
+    // Restore the original stdin if it was modified
+    if let Some(fd) = original_stdin_fd {
+        if unsafe { dup2(fd, STDIN_FILENO) } == -1 {
+            return CommandResult {
+                stdout: "".to_string(),
+                stderr: "Failed to restore the original STDIN".to_string(),
+                exit_code: -1,
+            };
+        }
+        unsafe { close(fd) };
+    }
+
+    CommandResult {
+        stdout: captured_stdout,
+        stderr: captured_stderr
+            .split_once(':')
+            .map(|x| x.1)
+            .unwrap_or("")
+            .trim()
+            .to_string(),
+        exit_code: uumain_exit_status,
+    }
+}
+
+fn read_from_fd(fd: RawFd) -> String {
+    let mut captured_output = Vec::new();
+    let mut read_buffer = [0; 1024];
+    loop {
+        let bytes_read = unsafe {
+            libc::read(
+                fd,
+                read_buffer.as_mut_ptr() as *mut libc::c_void,
+                read_buffer.len(),
+            )
+        };
+
+        if bytes_read == -1 {
+            eprintln!("Failed to read from the pipe");
+            break;
+        }
+        if bytes_read == 0 {
+            break;
+        }
+        captured_output.extend_from_slice(&read_buffer[..bytes_read as usize]);
+    }
+
+    unsafe { libc::close(fd) };
+
+    String::from_utf8_lossy(&captured_output).into_owned()
+}
+
+pub fn run_gnu_cmd(
+    cmd_path: &str,
+    args: &[OsString],
+    check_gnu: bool,
+    pipe_input: Option<&str>,
+) -> Result<CommandResult, CommandResult> {
+    if check_gnu {
+        match is_gnu_cmd(cmd_path) {
+            Ok(_) => {} // if the check passes, do nothing
+            Err(e) => {
+                // Convert the io::Error into the function's error type
+                return Err(CommandResult {
+                    stdout: String::new(),
+                    stderr: e.to_string(),
+                    exit_code: -1,
+                });
+            }
+        }
+    }
+
+    let mut command = Command::new(cmd_path);
+    for arg in args {
+        command.arg(arg);
+    }
+
+    // See https://github.com/uutils/coreutils/issues/6794
+    // uutils' coreutils is not locale-aware, and aims to mirror/be compatible with GNU Core Utilities's LC_ALL=C behavior
+    command.env("LC_ALL", "C");
+
+    let output = if let Some(input_str) = pipe_input {
+        // We have an pipe input
+        command
+            .stdin(Stdio::piped())
+            .stdout(Stdio::piped())
+            .stderr(Stdio::piped());
+
+        let mut child = command.spawn().expect("Failed to execute command");
+        let child_stdin = child.stdin.as_mut().unwrap();
+        child_stdin
+            .write_all(input_str.as_bytes())
+            .expect("Failed to write to stdin");
+
+        match child.wait_with_output() {
+            Ok(output) => output,
+            Err(e) => {
+                return Err(CommandResult {
+                    stdout: String::new(),
+                    stderr: e.to_string(),
+                    exit_code: -1,
+                });
+            }
+        }
+    } else {
+        // Just run with args
+        match command.output() {
+            Ok(output) => output,
+            Err(e) => {
+                return Err(CommandResult {
+                    stdout: String::new(),
+                    stderr: e.to_string(),
+                    exit_code: -1,
+                });
+            }
+        }
+    };
+    let exit_code = output.status.code().unwrap_or(-1);
+    // Here we get stdout and stderr as Strings
+    let stdout = String::from_utf8_lossy(&output.stdout).to_string();
+    let stderr = String::from_utf8_lossy(&output.stderr).to_string();
+    let stderr = stderr
+        .split_once(':')
+        .map(|x| x.1)
+        .unwrap_or("")
+        .trim()
+        .to_string();
+
+    if output.status.success() || !check_gnu {
+        Ok(CommandResult {
+            stdout,
+            stderr,
+            exit_code,
+        })
+    } else {
+        Err(CommandResult {
+            stdout,
+            stderr,
+            exit_code,
+        })
+    }
+}
+
+/// Compare results from two different implementations of a command.
+///
+/// # Arguments
+/// * `test_type` - The command.
+/// * `input` - The input provided to the command.
+/// * `rust_result` - The result of running the command with the Rust implementation.
+/// * `gnu_result` - The result of running the command with the GNU implementation.
+/// * `fail_on_stderr_diff` - Whether to fail the test if there is a difference in stderr output.
+pub fn compare_result(
+    test_type: &str,
+    input: &str,
+    pipe_input: Option<&str>,
+    rust_result: &CommandResult,
+    gnu_result: &CommandResult,
+    fail_on_stderr_diff: bool,
+) {
+    print_section(format!("Compare result for: {test_type} {input}"));
+
+    if let Some(pipe) = pipe_input {
+        println!("Pipe: {pipe}");
+    }
+
+    let mut discrepancies = Vec::new();
+    let mut should_panic = false;
+
+    if rust_result.stdout.trim() != gnu_result.stdout.trim() {
+        discrepancies.push("stdout differs");
+        println!("Rust stdout:");
+        print_or_empty(rust_result.stdout.as_str());
+        println!("GNU stdout:");
+        print_or_empty(gnu_result.stdout.as_ref());
+        print_diff(&rust_result.stdout, &gnu_result.stdout);
+        should_panic = true;
+    }
+
+    if rust_result.stderr.trim() != gnu_result.stderr.trim() {
+        discrepancies.push("stderr differs");
+        println!("Rust stderr:");
+        print_or_empty(rust_result.stderr.as_str());
+        println!("GNU stderr:");
+        print_or_empty(gnu_result.stderr.as_str());
+        print_diff(&rust_result.stderr, &gnu_result.stderr);
+        if fail_on_stderr_diff {
+            should_panic = true;
+        }
+    }
+
+    if rust_result.exit_code != gnu_result.exit_code {
+        discrepancies.push("exit code differs");
+        println!(
+            "Different exit code: (Rust: {}, GNU: {})",
+            rust_result.exit_code, gnu_result.exit_code
+        );
+        should_panic = true;
+    }
+
+    if discrepancies.is_empty() {
+        print_end_with_status("Same behavior", true);
+    } else {
+        print_with_style(
+            format!("Discrepancies detected: {}", discrepancies.join(", ")),
+            Style::new().red(),
+        );
+        if should_panic {
+            print_end_with_status(
+                format!("Test failed and will panic for: {test_type} {input}"),
+                false,
+            );
+            panic!("Test failed for: {test_type} {input}");
+        } else {
+            print_end_with_status(
+                format!("Test completed with discrepancies for: {test_type} {input}"),
+                false,
+            );
+        }
+    }
+    println!();
+}
+
+pub fn generate_random_string(max_length: usize) -> String {
+    let mut rng = rand::rng();
+    let valid_utf8: Vec<char> = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"
+        .chars()
+        .collect();
+    let invalid_utf8 = [0xC3, 0x28]; // Invalid UTF-8 sequence
+    let mut result = String::new();
+
+    for _ in 0..rng.random_range(0..=max_length) {
+        if rng.random_bool(0.9) {
+            let ch = valid_utf8.choose(&mut rng).unwrap();
+            result.push(*ch);
+        } else {
+            let ch = invalid_utf8.choose(&mut rng).unwrap();
+            if let Some(c) = char::from_u32(*ch as u32) {
+                result.push(c);
+            }
+        }
+    }
+
+    result
+}
+
+#[allow(dead_code)]
+pub fn generate_random_file() -> Result<String, std::io::Error> {
+    let mut rng = rand::rng();
+    let file_name: String = (0..10)
+        .map(|_| rng.random_range(b'a'..=b'z') as char)
+        .collect();
+    let mut file_path = temp_dir();
+    file_path.push(file_name);
+
+    let mut file = File::create(&file_path)?;
+
+    let content_length = rng.random_range(10..1000);
+    let content: String = (0..content_length)
+        .map(|_| (rng.random_range(b' '..=b'~') as char))
+        .collect();
+
+    file.write_all(content.as_bytes())?;
+
+    Ok(file_path.to_str().unwrap().to_string())
+}
+
+#[allow(dead_code)]
+pub fn replace_fuzz_binary_name(cmd: &str, result: &mut CommandResult) {
+    let fuzz_bin_name = format!("fuzz/target/x86_64-unknown-linux-gnu/release/fuzz_{cmd}");
+
+    result.stdout = result.stdout.replace(&fuzz_bin_name, cmd);
+    result.stderr = result.stderr.replace(&fuzz_bin_name, cmd);
+}

fuzz/uufuzz/src/pretty_print.rs

@@ -0,0 +1,69 @@
+// 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 std::fmt;
+
+use console::{Style, style};
+use similar::TextDiff;
+
+pub fn print_section<S: fmt::Display>(s: S) {
+    println!("{}", style(format!("=== {s}")).bold());
+}
+
+pub fn print_subsection<S: fmt::Display>(s: S) {
+    println!("{}", style(format!("--- {s}")).bright());
+}
+
+#[allow(dead_code)]
+pub fn print_test_begin<S: fmt::Display>(msg: S) {
+    println!(
+        "{} {} {}",
+        style("===").bold(), // Kind of gray
+        style("TEST").black().on_yellow().bold(),
+        style(msg).bold()
+    );
+}
+
+pub fn print_end_with_status<S: fmt::Display>(msg: S, ok: bool) {
+    let ok = if ok {
+        style(" OK ").black().on_green().bold()
+    } else {
+        style(" KO ").black().on_red().bold()
+    };
+
+    println!(
+        "{} {ok} {}",
+        style("===").bold(), // Kind of gray
+        style(msg).bold()
+    );
+}
+
+pub fn print_or_empty(s: &str) {
+    let to_print = if s.is_empty() { "(empty)" } else { s };
+
+    println!("{}", style(to_print).dim());
+}
+
+pub fn print_with_style<S: fmt::Display>(msg: S, style: Style) {
+    println!("{}", style.apply_to(msg));
+}
+
+pub fn print_diff(got: &str, expected: &str) {
+    let diff = TextDiff::from_lines(got, expected);
+
+    print_subsection("START diff");
+
+    for change in diff.iter_all_changes() {
+        let (sign, style) = match change.tag() {
+            similar::ChangeTag::Equal => (" ", Style::new().dim()),
+            similar::ChangeTag::Delete => ("-", Style::new().red()),
+            similar::ChangeTag::Insert => ("+", Style::new().green()),
+        };
+        print!("{}{}", style.apply_to(sign).bold(), style.apply_to(change));
+    }
+
+    print_subsection("END diff");
+    println!();
+}