libblobd_kv/
util.rs

1#![allow(unused)]
2
3use chrono::Utc;
4use off64::u32;
5use off64::u64;
6use parking_lot::Mutex;
7use std::ops::Index;
8use std::sync::Arc;
9
10// This is different from std::io::Read as it allows peeking arbitrary offsets.
11pub(crate) struct ByteConsumer<T: AsRef<[u8]>> {
12  data: T,
13  offset: usize,
14}
15
16impl<T: AsRef<[u8]>> ByteConsumer<T> {
17  pub fn new(data: T) -> ByteConsumer<T> {
18    Self { data, offset: 0 }
19  }
20
21  pub fn consume(&mut self, n: usize) -> &[u8] {
22    let res = &self.data.as_ref()[self.offset..self.offset + n];
23    self.offset += n;
24    res
25  }
26
27  pub fn consumed(&self) -> usize {
28    self.offset
29  }
30
31  pub fn remaining(&self) -> usize {
32    self.data.as_ref().len() - self.offset
33  }
34
35  pub fn is_empty(&self) -> bool {
36    self.offset >= self.data.as_ref().len()
37  }
38}
39
40impl<T: AsRef<[u8]>> Index<usize> for ByteConsumer<T> {
41  type Output = u8;
42
43  fn index(&self, index: usize) -> &Self::Output {
44    &self.data.as_ref()[self.offset + index]
45  }
46}
47
48pub(crate) fn get_now_ms() -> u64 {
49  u64!(Utc::now().timestamp_millis())
50}
51
52pub(crate) fn get_now_sec() -> u64 {
53  u64!(Utc::now().timestamp())
54}
55
56pub(crate) fn get_now_hour() -> u32 {
57  u32!(Utc::now().timestamp() / 60 / 60)
58}
59
60pub(crate) fn div_ceil(n: u64, d: u64) -> u64 {
61  (n / d) + ((n % d != 0) as u64)
62}
63
64pub(crate) fn div_mod_pow2(val: u64, pow2: u8) -> (u64, u64) {
65  (val >> pow2, val & ((1 << pow2) - 1))
66}
67
68pub(crate) fn div_pow2(val: u64, pow2: u8) -> u64 {
69  let (div, _) = div_mod_pow2(val, pow2);
70  div
71}
72
73pub(crate) fn mod_pow2(val: u64, pow2: u8) -> u64 {
74  let (_, mod_) = div_mod_pow2(val, pow2);
75  mod_
76}
77
78pub(crate) fn mul_pow2(val: u64, pow2: u8) -> u64 {
79  val << pow2
80}
81
82// Round up to next `2^pow2`.
83pub(crate) fn ceil_pow2(val: u64, pow2: u8) -> u64 {
84  let (mut div, mod_) = div_mod_pow2(val, pow2);
85  if mod_ != 0 {
86    div += 1;
87  };
88  div << pow2
89}
90
91// Round down to previous `2^pow2`.
92pub(crate) fn floor_pow2(val: u64, pow2: u8) -> u64 {
93  let (mut div, mod_) = div_mod_pow2(val, pow2);
94  div << pow2
95}
96
97pub(crate) fn is_multiple_of_pow2(val: u64, pow2: u8) -> bool {
98  let (_, mod_) = div_mod_pow2(val, pow2);
99  mod_ == 0
100}
101
102#[cfg(test)]
103mod tests {
104  use crate::util::ceil_pow2;
105  use crate::util::div_ceil;
106  use crate::util::div_mod_pow2;
107
108  #[test]
109  fn test_div_ceil() {
110    assert_eq!(div_ceil(0, 1), 0);
111    assert_eq!(div_ceil(0, 2), 0);
112    assert_eq!(div_ceil(0, 3), 0);
113    assert_eq!(div_ceil(1, 2), 1);
114    assert_eq!(div_ceil(1, 3), 1);
115    assert_eq!(div_ceil(10, 3), 4);
116    assert_eq!(div_ceil(2, 2), 1);
117    assert_eq!(div_ceil(3, 2), 2);
118  }
119
120  #[test]
121  fn test_div_mod_pow2() {
122    assert_eq!(div_mod_pow2(0, 0), (0, 0));
123    assert_eq!(div_mod_pow2(0, 1), (0, 0));
124    assert_eq!(div_mod_pow2(0, 2), (0, 0));
125    assert_eq!(div_mod_pow2(1, 0), (1, 0));
126    assert_eq!(div_mod_pow2(1, 1), (0, 1));
127    assert_eq!(div_mod_pow2(1, 2), (0, 1));
128    assert_eq!(div_mod_pow2(5, 2), (1, 1));
129    assert_eq!(div_mod_pow2(10, 2), (2, 2));
130    assert_eq!(div_mod_pow2(16392, 6), (256, 8));
131    assert_eq!(div_mod_pow2(16393, 6), (256, 9));
132  }
133
134  #[test]
135  fn test_ceil_pow2() {
136    assert_eq!(ceil_pow2(0, 0), 0);
137    assert_eq!(ceil_pow2(1, 0), 1);
138    assert_eq!(ceil_pow2(2, 0), 2);
139    assert_eq!(ceil_pow2(3, 0), 3);
140    assert_eq!(ceil_pow2(3, 1), 4);
141    assert_eq!(ceil_pow2(0, 2), 0);
142    assert_eq!(ceil_pow2(1, 2), 4);
143    assert_eq!(ceil_pow2(3, 2), 4);
144    assert_eq!(ceil_pow2(4, 2), 4);
145    assert_eq!(ceil_pow2(4, 8), 256);
146    assert_eq!(ceil_pow2(5, 8), 256);
147  }
148}
libblobd_kv/util.rs

libblobd_kv/
util.rs
