gemachain_program/
slot_hashes.rs

1//! named accounts for synthesized data accounts for bank state, etc.
2//!
3//! this account carries the Bank's most recent bank hashes for some N parents
4//!
5use crate::hash::Hash;
6use std::{iter::FromIterator, ops::Deref};
7
8pub const MAX_ENTRIES: usize = 512; // about 2.5 minutes to get your vote in
9
10pub use crate::clock::Slot;
11
12pub type SlotHash = (Slot, Hash);
13
14#[repr(C)]
15#[derive(Serialize, Deserialize, PartialEq, Debug, Default)]
16pub struct SlotHashes(Vec<SlotHash>);
17
18impl SlotHashes {
19    pub fn add(&mut self, slot: Slot, hash: Hash) {
20        match self.binary_search_by(|(probe, _)| slot.cmp(probe)) {
21            Ok(index) => (self.0)[index] = (slot, hash),
22            Err(index) => (self.0).insert(index, (slot, hash)),
23        }
24        (self.0).truncate(MAX_ENTRIES);
25    }
26    #[allow(clippy::trivially_copy_pass_by_ref)]
27    pub fn get(&self, slot: &Slot) -> Option<&Hash> {
28        self.binary_search_by(|(probe, _)| slot.cmp(probe))
29            .ok()
30            .map(|index| &self[index].1)
31    }
32    pub fn new(slot_hashes: &[SlotHash]) -> Self {
33        let mut slot_hashes = slot_hashes.to_vec();
34        slot_hashes.sort_by(|(a, _), (b, _)| b.cmp(a));
35        Self(slot_hashes)
36    }
37}
38
39impl FromIterator<(Slot, Hash)> for SlotHashes {
40    fn from_iter<I: IntoIterator<Item = (Slot, Hash)>>(iter: I) -> Self {
41        Self(iter.into_iter().collect())
42    }
43}
44
45impl Deref for SlotHashes {
46    type Target = Vec<SlotHash>;
47    fn deref(&self) -> &Self::Target {
48        &self.0
49    }
50}
51
52#[cfg(test)]
53mod tests {
54    use super::*;
55    use crate::hash::hash;
56
57    #[test]
58    fn test() {
59        let mut slot_hashes = SlotHashes::new(&[(1, Hash::default()), (3, Hash::default())]);
60        slot_hashes.add(2, Hash::default());
61        assert_eq!(
62            slot_hashes,
63            SlotHashes(vec![
64                (3, Hash::default()),
65                (2, Hash::default()),
66                (1, Hash::default()),
67            ])
68        );
69
70        let mut slot_hashes = SlotHashes::new(&[]);
71        for i in 0..MAX_ENTRIES + 1 {
72            slot_hashes.add(
73                i as u64,
74                hash(&[(i >> 24) as u8, (i >> 16) as u8, (i >> 8) as u8, i as u8]),
75            );
76        }
77        for i in 0..MAX_ENTRIES {
78            assert_eq!(slot_hashes[i].0, (MAX_ENTRIES - i) as u64);
79        }
80
81        assert_eq!(slot_hashes.len(), MAX_ENTRIES);
82    }
83}
gemachain_program/slot_hashes.rs

gemachain_program/
slot_hashes.rs
