proxmox/proxmox-uuid/src/wasm.rs
Thomas Lamprecht 800cf63a8a uuid: rustfmt
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
2022-04-10 12:34:01 +02:00

103 lines
3.0 KiB
Rust

use std::fmt;
use crate::Uuid;
pub fn uuid_generate(out: *mut [u8; 16]) {
// TODO: implement soemthing better than this
let time = js_sys::Date::now() as u64;
let random1 = (js_sys::Math::random() * f64::MAX) as u64;
let random2 = (js_sys::Math::random() * f64::MAX) as u64;
let random3 = (js_sys::Math::random() * f64::MAX) as u64;
let random4 = (js_sys::Math::random() * f64::MAX) as u64;
let mut bytes1 = [0u8; 16];
let mut bytes2 = [0u8; 16];
let mut bytes3 = [0u8; 16];
bytes1[0..8].copy_from_slice(&random1.to_le_bytes());
bytes1[8..16].copy_from_slice(&random2.to_le_bytes());
let random3 = random3.to_le_bytes();
bytes2[0..4].copy_from_slice(&random3[0..4]);
bytes2[4..12].copy_from_slice(&random4.to_le_bytes());
bytes2[12..16].copy_from_slice(&random3[4..8]);
bytes3[0..8].copy_from_slice(&time.to_le_bytes());
bytes3[8..16].copy_from_slice(&time.to_le_bytes());
if out.is_null() {
return;
}
let out = unsafe { out.as_mut().unwrap() };
for i in 0..16 {
let v = bytes1[i] ^ bytes2[i] ^ bytes3[i];
out[i] = v;
}
}
// Copied from uuid crate: https://github.com/uuid-rs/uuid.git
// adopted types to our needs
const UPPER: [u8; 16] = [
b'0', b'1', b'2', b'3', b'4', b'5', b'6', b'7', b'8', b'9', b'A', b'B', b'C', b'D', b'E', b'F',
];
const LOWER: [u8; 16] = [
b'0', b'1', b'2', b'3', b'4', b'5', b'6', b'7', b'8', b'9', b'a', b'b', b'c', b'd', b'e', b'f',
];
/// The segments of a UUID's [u8; 16] corresponding to each group.
const BYTE_POSITIONS: [usize; 6] = [0, 4, 6, 8, 10, 16];
/// The locations that hyphens are written into the buffer, after each
/// group.
const HYPHEN_POSITIONS: [usize; 4] = [8, 13, 18, 23];
pub fn uuid_encode(uuid: &[u8; 16], upper: bool) -> String {
let mut buffer = [0u8; 36];
let hex = if upper { &UPPER } else { &LOWER };
for group in 0..5 {
let hyphens_before = group;
for idx in BYTE_POSITIONS[group]..BYTE_POSITIONS[group + 1] {
let b = uuid[idx];
let out_idx = hyphens_before + 2 * idx;
buffer[out_idx] = hex[(b >> 4) as usize];
buffer[out_idx + 1] = hex[(b & 0b1111) as usize];
}
if group != 4 {
buffer[HYPHEN_POSITIONS[group]] = b'-';
}
}
std::str::from_utf8(&mut buffer[..])
.expect("found non-ASCII output characters while encoding a UUID")
.to_string()
}
impl fmt::LowerHex for Uuid {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(f, "{}", uuid_encode(self.as_bytes(), false))
}
}
impl fmt::UpperHex for Uuid {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(f, "{}", uuid_encode(self.as_bytes(), true))
}
}
#[cfg(feature = "serde")]
impl serde::Serialize for Uuid {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: serde::Serializer,
{
serializer.serialize_str(&uuid_encode(self.as_bytes(), false))
}
}