intcmp(1): initial rust impl

src/intcmp.rs

@@ -0,0 +1,78 @@
+/*
+ * Copyright (c) 2023–2024 DTB <trinity@trinity.moe>
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ *
+ * This program is free software: you can redistribute it and/or modify it under
+ * the terms of the GNU Affero General Public License as published by the Free
+ * Software Foundation, either version 3 of the License, or (at your option) any
+ * later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see https://www.gnu.org/licenses/.
+ */
+
+// /* 0b00? */		/*                     Equal | -e  | 0b001 | 1 */
+// #define EQUAL	0x01	/*                   Greater | -g  | 0b010 | 2 */
+// /* 0b0?0 */		/*          Greater or Equal | -ge | 0b011 | 3 */
+// #define GREATER	0x02	/*                      Less | -l  | 0b100 | 4 */
+// /* 0b?00 */		/*             Less or Equal | -le | 0b101 | 5 */
+// #define LESS	0x04	/* Inequal (Greater or Less) | -gl | 0b110 | 6 */
+
+use std::{
+	env::args,
+	process::ExitCode
+};
+
+fn usage(s: &str) -> ExitCode {
+	eprintln!("Usage: {} [-egl] integer integer...", s);
+	ExitCode::from(EX_USAGE as u8)
+}
+
+fn main() -> ExitCode {
+	let argv = args().collect::<Vec<String>>();
+	let mut can_eq = false;
+	let mut can_gt = false;
+	let mut can_lt = false;
+	let mut optind = 0;
+
+	if argv.len() < 3 { return usage(&argv[0]); }
+
+	while let Some(opt) = argv.getopt("egl") {
+		match opt.opt() {
+			Ok("e") => can_eq = true,
+			Ok("g") => can_gt = true,
+			Ok("l") => can_lt = true,
+			_ => { return usage(&argv[0]); },
+		}
+		optind = opt.ind();
+	}
+
+	if argv.len() - optind < 2 /* ref cmp */ { return usage(&argv[0]); }
+
+	let mut reference = None;
+	let mut cmpn: usize;
+
+	for arg in argv.iter().skip(optind) {
+		match arg.parse::<usize>() {
+			Ok(n) => cmpn = n,
+			_ => {
+				eprintln!("{}: {}: Invalid integer", &argv[0], arg);
+				return ExitCode::from(EX_USAGE as u8);
+			}
+		}
+
+		if let Some(refn) = reference {
+			if (!can_eq && refn == cmpn)
+					|| (!can_gt && refn > cmpn)
+					|| (!can_lt && refn < cmpn)
+				{ return ExitCode::FAILURE; }
+		}
+	}
+
+	ExitCode::SUCCESS
+}