mirror of https://github.com/nextgraph-org/rkv.git
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
133 lines
3.7 KiB
133 lines
3.7 KiB
// Copyright 2018 Mozilla
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License"); you may not use
|
|
// this file except in compliance with the License. You may obtain a copy of the
|
|
// License at http://www.apache.org/licenses/LICENSE-2.0
|
|
// Unless required by applicable law or agreed to in writing, software distributed
|
|
// under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
|
|
// CONDITIONS OF ANY KIND, either express or implied. See the License for the
|
|
// specific language governing permissions and limitations under the License.
|
|
|
|
use std::marker::PhantomData;
|
|
|
|
use crate::{
|
|
backend::{BackendDatabase, BackendFlags, BackendIter, BackendRoCursor, BackendRwTransaction},
|
|
error::StoreError,
|
|
helpers::read_transform,
|
|
readwrite::{Readable, Writer},
|
|
value::Value,
|
|
};
|
|
|
|
type EmptyResult = Result<(), StoreError>;
|
|
|
|
#[derive(Debug, Eq, PartialEq, Copy, Clone)]
|
|
pub struct MultiStore<D> {
|
|
db: D,
|
|
}
|
|
|
|
pub struct Iter<'i, I> {
|
|
iter: I,
|
|
phantom: PhantomData<&'i ()>,
|
|
}
|
|
|
|
impl<D> MultiStore<D>
|
|
where
|
|
D: BackendDatabase,
|
|
{
|
|
pub(crate) fn new(db: D) -> MultiStore<D> {
|
|
MultiStore { db }
|
|
}
|
|
|
|
/// Provides a cursor to all of the values for the duplicate entries that match this
|
|
/// key
|
|
pub fn get<'r, R, I, C, K>(&self, reader: &'r R, k: K) -> Result<Iter<'r, I>, StoreError>
|
|
where
|
|
R: Readable<'r, Database = D, RoCursor = C>,
|
|
I: BackendIter<'r>,
|
|
C: BackendRoCursor<'r, Iter = I>,
|
|
K: AsRef<[u8]> + 'r,
|
|
{
|
|
let cursor = reader.open_ro_cursor(&self.db)?;
|
|
let iter = cursor.into_iter_dup_of(k);
|
|
|
|
Ok(Iter {
|
|
iter,
|
|
phantom: PhantomData,
|
|
})
|
|
}
|
|
|
|
/// Provides the first value that matches this key
|
|
pub fn get_first<'r, R, K>(&self, reader: &'r R, k: K) -> Result<Option<Value<'r>>, StoreError>
|
|
where
|
|
R: Readable<'r, Database = D>,
|
|
K: AsRef<[u8]>,
|
|
{
|
|
reader.get(&self.db, &k)
|
|
}
|
|
|
|
/// Insert a value at the specified key.
|
|
/// This put will allow duplicate entries. If you wish to have duplicate entries
|
|
/// rejected, use the `put_with_flags` function and specify NO_DUP_DATA
|
|
pub fn put<T, K>(&self, writer: &mut Writer<T>, k: K, v: &Value) -> EmptyResult
|
|
where
|
|
T: BackendRwTransaction<Database = D>,
|
|
K: AsRef<[u8]>,
|
|
{
|
|
writer.put(&self.db, &k, v, T::Flags::empty())
|
|
}
|
|
|
|
pub fn put_with_flags<T, K>(
|
|
&self,
|
|
writer: &mut Writer<T>,
|
|
k: K,
|
|
v: &Value,
|
|
flags: T::Flags,
|
|
) -> EmptyResult
|
|
where
|
|
T: BackendRwTransaction<Database = D>,
|
|
K: AsRef<[u8]>,
|
|
{
|
|
writer.put(&self.db, &k, v, flags)
|
|
}
|
|
|
|
pub fn delete_all<T, K>(&self, writer: &mut Writer<T>, k: K) -> EmptyResult
|
|
where
|
|
T: BackendRwTransaction<Database = D>,
|
|
K: AsRef<[u8]>,
|
|
{
|
|
writer.delete(&self.db, &k, None)
|
|
}
|
|
|
|
pub fn delete<T, K>(&self, writer: &mut Writer<T>, k: K, v: &Value) -> EmptyResult
|
|
where
|
|
T: BackendRwTransaction<Database = D>,
|
|
K: AsRef<[u8]>,
|
|
{
|
|
writer.delete(&self.db, &k, Some(&v.to_bytes()?))
|
|
}
|
|
|
|
pub fn clear<T>(&self, writer: &mut Writer<T>) -> EmptyResult
|
|
where
|
|
T: BackendRwTransaction<Database = D>,
|
|
{
|
|
writer.clear(&self.db)
|
|
}
|
|
}
|
|
|
|
impl<'i, I> Iterator for Iter<'i, I>
|
|
where
|
|
I: BackendIter<'i>,
|
|
{
|
|
type Item = Result<(&'i [u8], Value<'i>), StoreError>;
|
|
|
|
fn next(&mut self) -> Option<Self::Item> {
|
|
match self.iter.next() {
|
|
None => None,
|
|
Some(Ok((key, bytes))) => match read_transform(Ok(bytes)) {
|
|
Ok(val) => Some(Ok((key, val))),
|
|
Err(err) => Some(Err(err)),
|
|
},
|
|
Some(Err(err)) => Some(Err(err.into())),
|
|
}
|
|
}
|
|
}
|
|
|