aerogramme/src/timestamp.rs

65 lines
1.7 KiB
Rust

use rand::prelude::*;
use std::str::FromStr;
use std::time::{SystemTime, UNIX_EPOCH};
/// Returns milliseconds since UNIX Epoch
pub fn now_msec() -> u64 {
SystemTime::now()
.duration_since(UNIX_EPOCH)
.expect("Fix your clock :o")
.as_millis() as u64
}
#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Debug)]
pub struct Timestamp {
pub msec: u64,
pub rand: u64,
}
impl Timestamp {
#[allow(dead_code)]
// 2023-05-15 try to make clippy happy and not sure if this fn will be used in the future.
pub fn now() -> Self {
let mut rng = thread_rng();
Self {
msec: now_msec(),
rand: rng.gen::<u64>(),
}
}
pub fn after(other: &Self) -> Self {
let mut rng = thread_rng();
Self {
msec: std::cmp::max(now_msec(), other.msec + 1),
rand: rng.gen::<u64>(),
}
}
pub fn zero() -> Self {
Self { msec: 0, rand: 0 }
}
}
impl ToString for Timestamp {
fn to_string(&self) -> String {
let mut bytes = [0u8; 16];
bytes[0..8].copy_from_slice(&u64::to_be_bytes(self.msec));
bytes[8..16].copy_from_slice(&u64::to_be_bytes(self.rand));
hex::encode(bytes)
}
}
impl FromStr for Timestamp {
type Err = &'static str;
fn from_str(s: &str) -> Result<Timestamp, &'static str> {
let bytes = hex::decode(s).map_err(|_| "invalid hex")?;
if bytes.len() != 16 {
return Err("bad length");
}
Ok(Self {
msec: u64::from_be_bytes(bytes[0..8].try_into().unwrap()),
rand: u64::from_be_bytes(bytes[8..16].try_into().unwrap()),
})
}
}