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// { dg-additional-options "-frust-compile-until=lowering" }
#[lang = "sized"]
trait Sized {}
enum Result<T, E> {
Ok(T),
Err(E),
}
use Result::{Err, Ok};
struct Utf8Error;
const CONT_MASK: u8 = 15;
const TAG_CONT_U8: u8 = 15;
#[inline(always)]
pub fn run_utf8_validation(v: &[u8]) -> Result<(), Utf8Error> {
let mut index = 0;
let len = 64;
let usize_bytes = 8;
let ascii_block_size = 2 * usize_bytes;
let blocks_end = if len >= ascii_block_size {
len - ascii_block_size + 1
} else {
0
};
while index < len {
let old_offset = index;
macro_rules! err {
($error_len: expr) => {
return Err(Utf8Error)
};
}
macro_rules! next {
() => {{
index += 1;
// we needed data, but there was none: error!
if index >= len {
err!(None)
}
v[index]
}};
}
let first = v[index];
if first >= 128 {
let w = 15;
// 2-byte encoding is for codepoints \u{0080} to \u{07ff}
// first C2 80 last DF BF
// 3-byte encoding is for codepoints \u{0800} to \u{ffff}
// first E0 A0 80 last EF BF BF
// excluding surrogates codepoints \u{d800} to \u{dfff}
// ED A0 80 to ED BF BF
// 4-byte encoding is for codepoints \u{1000}0 to \u{10ff}ff
// first F0 90 80 80 last F4 8F BF BF
//
// Use the UTF-8 syntax from the RFC
//
// https://tools.ietf.org/html/rfc3629
// UTF8-1 = %x00-7F
// UTF8-2 = %xC2-DF UTF8-tail
// UTF8-3 = %xE0 %xA0-BF UTF8-tail / %xE1-EC 2( UTF8-tail ) /
// %xED %x80-9F UTF8-tail / %xEE-EF 2( UTF8-tail )
// UTF8-4 = %xF0 %x90-BF 2( UTF8-tail ) / %xF1-F3 3( UTF8-tail ) /
// %xF4 %x80-8F 2( UTF8-tail )
match w {
2 => {
if next!() & !CONT_MASK != TAG_CONT_U8 {
err!(Some(1))
}
}
3 => {
match (first, next!()) {
(0xE0, 0xA0..=0xBF)
| (0xE1..=0xEC, 0x80..=0xBF)
| (0xED, 0x80..=0x9F)
| (0xEE..=0xEF, 0x80..=0xBF) => {}
_ => err!(Some(1)),
}
if next!() & !CONT_MASK != TAG_CONT_U8 {
err!(Some(2))
}
}
4 => {
match (first, next!()) {
(0xF0, 0x90..=0xBF) | (0xF1..=0xF3, 0x80..=0xBF) | (0xF4, 0x80..=0x8F) => {}
_ => err!(Some(1)),
}
if next!() & !CONT_MASK != TAG_CONT_U8 {
err!(Some(2))
}
if next!() & !CONT_MASK != TAG_CONT_U8 {
err!(Some(3))
}
}
_ => err!(Some(1)),
}
index += 1;
} else {
index += 1;
}
}
Ok(())
}
fn main() {}
|
