Files
nanoreth/crates/storage/db/src/snapshot/cursor.rs

109 lines
3.2 KiB
Rust

use super::mask::{ColumnSelectorOne, ColumnSelectorThree, ColumnSelectorTwo};
use crate::table::Decompress;
use derive_more::{Deref, DerefMut};
use reth_interfaces::provider::ProviderResult;
use reth_nippy_jar::{MmapHandle, NippyJar, NippyJarCursor};
use reth_primitives::{snapshot::SegmentHeader, B256};
/// Cursor of a snapshot segment.
#[derive(Debug, Deref, DerefMut)]
pub struct SnapshotCursor<'a>(NippyJarCursor<'a, SegmentHeader>);
impl<'a> SnapshotCursor<'a> {
/// Returns a new [`SnapshotCursor`].
pub fn new(jar: &'a NippyJar<SegmentHeader>, mmap_handle: MmapHandle) -> ProviderResult<Self> {
Ok(Self(NippyJarCursor::with_handle(jar, mmap_handle)?))
}
/// Returns the current `BlockNumber` or `TxNumber` of the cursor depending on the kind of
/// snapshot segment.
pub fn number(&self) -> u64 {
self.row_index() + self.jar().user_header().start()
}
/// Gets a row of values.
pub fn get(
&mut self,
key_or_num: KeyOrNumber<'_>,
mask: usize,
) -> ProviderResult<Option<Vec<&'_ [u8]>>> {
let row = match key_or_num {
KeyOrNumber::Key(k) => self.row_by_key_with_cols(k, mask),
KeyOrNumber::Number(n) => {
let offset = self.jar().user_header().start();
if offset > n {
return Ok(None)
}
self.row_by_number_with_cols((n - offset) as usize, mask)
}
}?;
Ok(row)
}
/// Gets one column value from a row.
pub fn get_one<M: ColumnSelectorOne>(
&mut self,
key_or_num: KeyOrNumber<'_>,
) -> ProviderResult<Option<M::FIRST>> {
let row = self.get(key_or_num, M::MASK)?;
match row {
Some(row) => Ok(Some(M::FIRST::decompress(row[0])?)),
None => Ok(None),
}
}
/// Gets two column values from a row.
pub fn get_two<M: ColumnSelectorTwo>(
&mut self,
key_or_num: KeyOrNumber<'_>,
) -> ProviderResult<Option<(M::FIRST, M::SECOND)>> {
let row = self.get(key_or_num, M::MASK)?;
match row {
Some(row) => Ok(Some((M::FIRST::decompress(row[0])?, M::SECOND::decompress(row[1])?))),
None => Ok(None),
}
}
/// Gets three column values from a row.
#[allow(clippy::type_complexity)]
pub fn get_three<M: ColumnSelectorThree>(
&mut self,
key_or_num: KeyOrNumber<'_>,
) -> ProviderResult<Option<(M::FIRST, M::SECOND, M::THIRD)>> {
let row = self.get(key_or_num, M::MASK)?;
match row {
Some(row) => Ok(Some((
M::FIRST::decompress(row[0])?,
M::SECOND::decompress(row[1])?,
M::THIRD::decompress(row[2])?,
))),
None => Ok(None),
}
}
}
/// Either a key _or_ a block/tx number
#[derive(Debug)]
pub enum KeyOrNumber<'a> {
/// A slice used as a key. Usually a block/tx hash
Key(&'a [u8]),
/// A block/tx number
Number(u64),
}
impl<'a> From<&'a B256> for KeyOrNumber<'a> {
fn from(value: &'a B256) -> Self {
KeyOrNumber::Key(value.as_slice())
}
}
impl<'a> From<u64> for KeyOrNumber<'a> {
fn from(value: u64) -> Self {
KeyOrNumber::Number(value)
}
}