1
0
src/npc.rs

120 lines
3.0 KiB
Rust

/*
* Copyright (c) 2023 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::{ stdin, stdout, Error, Read, Write },
process::ExitCode
};
extern crate getopt;
use getopt::{ Opt, Parser };
extern crate sysexits;
use sysexits::{ EX_OK, EX_OSERR, EX_USAGE };
fn oserr(s: &str, e: Error) -> ExitCode {
eprintln!("{}: {}", s, e);
ExitCode::from(EX_OSERR as u8)
}
fn usage(s: &str) -> ExitCode {
eprintln!("Usage: {} (-aet)", s);
ExitCode::from(EX_USAGE as u8)
}
fn main() -> ExitCode {
let argv = args().collect::<Vec<String>>();
let input = stdin();
let mut output = stdout().lock();
let mut opts = Parser::new(&argv, "7et");
let mut ascii = false;
let mut showend = false;
let mut showtab = false;
loop {
match opts.next() {
None => break,
Some(o) =>
match o {
Ok(Opt('7', None)) => ascii = true,
Ok(Opt('e', None)) => showend = true,
Ok(Opt('t', None)) => showtab = true,
_ => { return usage(&argv[0]); }
}
}
}
/* cat -v emulation */
if ascii {
let mut c: u8 = 0;
for r in input.bytes() {
match r {
Ok(v) => { c = v; },
Err(e) => { return oserr(&argv[0], e); }
}
/* If a given byte isn't expressable in ASCII, print "M-[char]",
* where char is the chosen representation of the byte with its
* high bit set to 0. */
if c & 0x80 /* 0b 1000 0000 */ != 0 { print!("M-"); }
c ^= 0x80;
/* ASCII DEL is represented as ^? */
if c == 0x7f as u8 {
if let Err(e) = output.write_all(b"^?") {
return oserr(&argv[0], e);
}
break;
}
if c == '\n' as u8 && showend {
if let Err(e) = output.write_all(b"$") {
return oserr(&argv[0], e);
}
}
/* ASCII visual characters are shown literally. */
if c >= ' ' as u8 || c == '\n' as u8
|| (!showtab && c == '\t' as u8) {
if let Err(e) = output.write_all(&[c]) {
return oserr(&argv[0], e);
}
}
/* Otherwise, characters are shown as their control code, with NUL
* being ^@ and successive characters shown as "^" catenated with
* successive visual characters past "@". */
else {
c += '@' as u8;
if let Err(e) = output.write_all(b"^") {
return oserr(&argv[0], e);
}
if let Err(e) = output.write_all(&[c]) {
return oserr(&argv[0], e);
}
}
}
} else {
eprintln!("not implemented");
}
ExitCode::from(EX_OK as u8)
}