60 lines
1.3 KiB
Rust
60 lines
1.3 KiB
Rust
use std::char;
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use std::fs::File;
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use std::io::prelude::*;
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use std::time::SystemTime;
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fn random_u64() -> u64 {
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let mut f = File::open("/dev/urandom").unwrap();
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let mut buffer = [0; 8];
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// read exactly 10 bytes
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f.read_exact(&mut buffer).unwrap();
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u64::from(buffer[0])
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| (u64::from(buffer[1]) << 8)
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| (u64::from(buffer[2]) << 16)
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| (u64::from(buffer[3]) << 24)
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| (u64::from(buffer[4]) << 32)
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| (u64::from(buffer[5]) << 40)
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| (u64::from(buffer[6]) << 48)
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| (u64::from(buffer[7]) << 56)
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}
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fn clock() -> u64 {
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SystemTime::now()
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.duration_since(SystemTime::UNIX_EPOCH)
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.unwrap()
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.as_secs()
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}
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fn base36(mut m: u64) -> String {
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let mut stack = Vec::with_capacity(32);
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while m >= 36 {
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stack.push((m % 36) as u32);
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m /= 36;
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}
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let mut ret = String::with_capacity(stack.len());
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while let Some(d) = stack.pop() {
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ret.push(char::from_digit(d, 36).unwrap());
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}
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ret
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}
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pub fn gen_message_id(fqdn: &str) -> String {
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let clock = base36(clock());
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let rand = base36(random_u64());
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format!("<{}.{}@{}>", clock, rand, fqdn)
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}
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pub fn gen_boundary() -> String {
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let clock = base36(clock());
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let rand = base36(random_u64());
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let rand2 = base36(random_u64());
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format!("{}{}{}", rand, clock, rand2)
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}
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