Add new fuzzers: cut, sort, split and wc (#5760)

* fuzz: use thread to bypass the limitation of output

Closes: #5724

many thanks to @samueltardieu

* fuzz: enable seq as the stalled issue is fixed

* fuzz: add 4 more fuzzers

* fuzz: enable the 4 new fuzzers in the CI

* remove old import

Co-authored-by: Daniel Hofstetter <daniel.hofstetter@42dh.com>

* remove comment

Co-authored-by: Daniel Hofstetter <daniel.hofstetter@42dh.com>

* remove comment

Co-authored-by: Daniel Hofstetter <daniel.hofstetter@42dh.com>

* add more flags

Co-authored-by: Daniel Hofstetter <daniel.hofstetter@42dh.com>

* add space

Co-authored-by: Daniel Hofstetter <daniel.hofstetter@42dh.com>

* add a comment about sort local

Co-authored-by: Daniel Hofstetter <daniel.hofstetter@42dh.com>

* wrong copy/paste

Co-authored-by: Daniel Hofstetter <daniel.hofstetter@42dh.com>

* fuzz: import "std::env"

---------

Co-authored-by: Daniel Hofstetter <daniel.hofstetter@42dh.com>

fuzz/fuzz_targets/fuzz_split.rs

@@ -0,0 +1,105 @@
+// 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.
+// spell-checker:ignore parens
+
+#![no_main]
+use libfuzzer_sys::fuzz_target;
+use uu_split::uumain;
+
+use rand::Rng;
+use std::ffi::OsString;
+
+mod fuzz_common;
+use crate::fuzz_common::{
+    compare_result, generate_and_run_uumain, generate_random_string, run_gnu_cmd, CommandResult,
+};
+static CMD_PATH: &str = "split";
+
+fn generate_split_args() -> String {
+    let mut rng = rand::thread_rng();
+    let mut args = Vec::new();
+
+    match rng.gen_range(0..=9) {
+        0 => {
+            args.push(String::from("-a")); // Suffix length
+            args.push(rng.gen_range(1..=8).to_string());
+        }
+        1 => {
+            args.push(String::from("--additional-suffix"));
+            args.push(generate_random_string(5)); // Random suffix
+        }
+        2 => {
+            args.push(String::from("-b")); // Bytes per output file
+            args.push(rng.gen_range(1..=1024).to_string() + "K");
+        }
+        3 => {
+            args.push(String::from("-C")); // Line bytes
+            args.push(rng.gen_range(1..=1024).to_string());
+        }
+        4 => args.push(String::from("-d")), // Use numeric suffixes
+        5 => args.push(String::from("-x")), // Use hex suffixes
+        6 => {
+            args.push(String::from("-l")); // Number of lines per output file
+            args.push(rng.gen_range(1..=1000).to_string());
+        }
+        7 => {
+            args.push(String::from("--filter"));
+            args.push(String::from("cat > /dev/null")); // Example filter command
+        }
+        8 => {
+            args.push(String::from("-t")); // Separator
+            args.push(String::from("\n")); // Newline as separator
+        }
+        9 => args.push(String::from("--verbose")), // Verbose
+        _ => (),
+    }
+
+    args.join(" ")
+}
+
+// Function to generate a random string of lines
+fn generate_random_lines(count: usize) -> String {
+    let mut rng = rand::thread_rng();
+    let mut lines = Vec::new();
+
+    for _ in 0..count {
+        lines.push(generate_random_string(rng.gen_range(1..=20)));
+    }
+
+    lines.join("\n")
+}
+
+fuzz_target!(|_data: &[u8]| {
+    let split_args = generate_split_args();
+    let mut args = vec![OsString::from("split")];
+    args.extend(split_args.split_whitespace().map(OsString::from));
+
+    let input_lines = generate_random_lines(10);
+
+    let rust_result = generate_and_run_uumain(&args, uumain, Some(&input_lines));
+
+    let gnu_result = match run_gnu_cmd(CMD_PATH, &args[1..], false, Some(&input_lines)) {
+        Ok(result) => result,
+        Err(error_result) => {
+            eprintln!("Failed to run GNU command:");
+            eprintln!("Stderr: {}", error_result.stderr);
+            eprintln!("Exit Code: {}", error_result.exit_code);
+            CommandResult {
+                stdout: String::new(),
+                stderr: error_result.stderr,
+                exit_code: error_result.exit_code,
+            }
+        }
+    };
+
+    compare_result(
+        "split",
+        &format!("{:?}", &args[1..]),
+        None,
+        &rust_result,
+        &gnu_result,
+        false, // Set to true if you want to fail on stderr diff
+    );
+});