| // Copyright 2012-2014 The Rust Project Developers. See the COPYRIGHT |
| // file at http://rust-lang.org/COPYRIGHT. |
| // |
| // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or |
| // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license |
| // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your |
| // option. This file may not be copied, modified, or distributed |
| // except according to those terms. |
| |
| // (This used to be in the Rust unicode crate, which is now gone, so we'll |
| // just include it inline.) |
| |
| // https://tools.ietf.org/html/rfc3629 |
| static UTF8_CHAR_WIDTH: [u8; 256] = [ |
| 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, |
| 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, // 0x1F |
| 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, |
| 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, // 0x3F |
| 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, |
| 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, // 0x5F |
| 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, |
| 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, // 0x7F |
| 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, |
| 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, // 0x9F |
| 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, |
| 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, // 0xBF |
| 0,0,2,2,2,2,2,2,2,2,2,2,2,2,2,2, |
| 2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2, // 0xDF |
| 3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3, // 0xEF |
| 4,4,4,4,4,0,0,0,0,0,0,0,0,0,0,0, // 0xFF |
| ]; |
| |
| /// Given a first byte, determine how many bytes are in this UTF-8 character |
| #[inline] |
| pub fn utf8_char_width(b: u8) -> usize { |
| return UTF8_CHAR_WIDTH[b as usize] as usize; |
| } |
