feeless 0.1.11

A Nano (cryptocurrency) node and utilities such as nano addresses, hashing blocks, signing, etc.
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77

use crate::node::header::Header;
use crate::node::wire::Wire;
use crate::{expect_len, hex_formatter};
use rand::RngCore;
use std::convert::TryFrom;

#[derive(Clone)]
#[repr(C)]
pub struct Cookie([u8; Cookie::LEN]);

impl Cookie {
    pub const LEN: usize = 32;

    pub fn random() -> Self {
        let mut cookie = Cookie([0u8; Self::LEN]);
        rand::thread_rng().fill_bytes(&mut cookie.0);
        cookie
    }

    pub fn as_bytes(&self) -> &[u8] {
        self.0.as_ref()
    }
}

impl std::fmt::Debug for Cookie {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        write!(f, "Cookie(")?;
        hex_formatter(f, self.0.as_ref())?;
        write!(f, ")")?;
        Ok(())
    }
}

impl Wire for Cookie {
    fn serialize(&self) -> Vec<u8> {
        Vec::from(self.as_bytes())
    }

    fn deserialize(_: Option<&Header>, data: &[u8]) -> anyhow::Result<Self>
    where
        Self: Sized,
    {
        Cookie::try_from(data)
    }

    fn len(_header: Option<&Header>) -> anyhow::Result<usize> {
        Ok(Cookie::LEN)
    }
}

impl TryFrom<&[u8]> for Cookie {
    type Error = anyhow::Error;

    fn try_from(value: &[u8]) -> Result<Self, Self::Error> {
        expect_len(value.len(), Self::LEN, "Cookie")?;

        // TODO: Self::zero()
        let mut cookie = Self::random();
        cookie.0.copy_from_slice(value);
        Ok(cookie)
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn sanity() {
        let mut c1 = Cookie::random();
        c1.0[0] = 0xff;
        c1.0[31] = 0x00;
        let c2 = Cookie::try_from(c1.0.as_ref()).unwrap();
        assert_eq!(c1.0[0], c2.0[0]);
        assert_eq!(c1.0[31], c2.0[31]);
    }
}