pschdir(1): rewrite in Rust

Makefile

@@ -124,8 +124,8 @@ build/bin/npc: src/npc.c build
 
 .PHONY: pschdir
 pschdir: build/bin/pschdir
-build/bin/pschdir: src/pschdir.c build
-	$(CC) $(CFLAGS) -o $@ src/pschdir.c
+build/bin/pschdir: src/pschdir.rs build
+	$(RUSTC) $(RUSTFLAGS) $(RUSTLIBS) -o $@ src/pschdir.rs
 
 .PHONY: rpn
 rpn: build/bin/rpn

src/pschdir.c

@@ -1,48 +0,0 @@
-/*
- * Copyright (c) 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/.
- */
-
-#include <errno.h> /* EACCESS, ELOOP, ENAMETOOLONG, ENOENT, ENOTDIR, errno */
-#include <stdio.h> /* fprintf(3), stderr */
-#include <string.h> /* strerror(3) */
-#include <sysexits.h> /* EX_OSERR, EX_NOPERM, EX_NOINPUT, EX_UNAVAILABLE,
-                       * EX_USAGE */
-#include <unistd.h> /* chdir(2) */
-
-char *program_name = "pschdir";
-
-int main(int argc, char *argv[]){
-	if (argc < 3) {
-		fprintf(stderr, "Usage: %s directory command [argument...]\n",
-			argv[0] == NULL ? program_name : argv[0]);
-		return EX_USAGE;
-	}
-
-	if(chdir(argv[1]) != 0){
-		fprintf(stderr, "%s: %s: %s\n", argv[0], argv[1], strerror(errno));
-
-		switch (errno) {
-			case ENAMETOOLONG:	return EX_OSERR;
-			case EACCES:      	return EX_NOPERM;
-			case ENOENT:
-			case ENOTDIR:     	return EX_NOINPUT;
-			default:          	return EX_UNAVAILABLE;
-		}
-	}
-
-	execvp(argv[2], &argv[2]);
-}

src/pschdir.rs

@@ -0,0 +1,61 @@
+/*
+ * 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/.
+ */
+
+use std::{ env::args, io::Error, process::{ Command, ExitCode } };
+
+extern crate strerror;
+use strerror::StrError;
+
+extern crate sysexits;
+use sysexits::{ EX_UNAVAILABLE, EX_USAGE };
+
+fn error(p: &str, n: &str, e: Error) -> ExitCode {
+	eprintln!("{}: {}: {}", p, n, e.strerror());
+	ExitCode::from(EX_UNAVAILABLE as u8)
+}
+
+fn main() -> ExitCode {
+	let argv = args().collect::<Vec<String>>();
+
+	if argv.len() < 3 {
+		eprintln!("Usage: {} directory command [argument]", argv[0]);
+		return ExitCode::from(EX_USAGE as u8);
+	}
+
+	let cmdargs = argv.iter().clone().skip(3).collect::<Vec<&String>>();
+
+	match Command::new(argv[2].clone())
+			.current_dir(argv[1].clone())
+			.args(cmdargs)
+			.spawn() {
+		Ok(mut child) => match child.wait() {
+			Ok(status) => {
+				match status.code() {
+					Some(code) => ExitCode::from(code as u8),
+					None => {
+						eprintln!("{}: {}: process terminated by signal",
+							argv[0], argv[2]);
+						ExitCode::FAILURE
+					}
+				}
+			},
+			Err(e) => error(&argv[0], &argv[2], e)
+		},
+		Err(e) => error(&argv[0], &argv[2], e)
+	}
+}