use super::{Reader, Result, Writer};
use crate::ChunkPointer;
use serde::{de::DeserializeOwned, Deserialize, Serialize};
#[derive(Serialize, Deserialize)]
pub struct SizedPointer {
chunk: ChunkPointer,
data_size: usize,
}
pub fn write<'writer, T: Serialize, W: 'writer + Writer + ?Sized>(
writer: &mut W,
serialize: impl Fn(T) -> Result<Vec<u8>>,
obj: T,
) -> Result<SizedPointer> {
let d = (serialize)(obj)?;
let data_size = d.len();
let chunk = writer.write(&d)?;
Ok(SizedPointer { chunk, data_size })
}
pub fn read<T: DeserializeOwned, R: Reader + ?Sized>(
reader: &mut R,
deserialize: impl Fn(&[u8]) -> Result<T>,
pointer: SizedPointer,
) -> Result<T> {
let mut serialized = vec![0; pointer.data_size];
reader.read_chunk(&pointer.chunk, &mut serialized)?;
deserialize(&serialized)
}