rsmt2d_rs/
codec.rs

1use eyre::Result;
2use reed_solomon_erasure::galois_8::ReedSolomon;
3
4use crate::{Matrix2D, Matrix3D};
5
6/// Codec handle for encoding and decoding data
7pub trait Codec {
8    /// Encode encodes original data, automatically extracting share size.
9    /// There must be no missing shares. Only returns parity shares.
10    fn encode(&self, data: Matrix2D) -> Result<Matrix2D>;
11    /// Decode sparse original + parity data, automatically extracting share size.
12    /// Missing shares must be nil. Returns original shares only.
13    fn decode(&self, data: Matrix3D) -> Result<Matrix3D>;
14    /// Return the max. number of chunks each code supports in a 2D square.
15    fn max_chunks(&self) -> usize;
16}
17
18pub fn new(data_len: usize) -> Result<Box<dyn Codec>> {
19    Ok(Box::new(ReedSolomonCodec::new(data_len)?))
20}
21
22const REED_SOLOMON_MAX_CHUNKS: usize = 32768 * 32768;
23
24/// Reed Solomon Codec implementation
25struct ReedSolomonCodec {
26    data_len: usize,
27    rs: ReedSolomon,
28}
29
30impl ReedSolomonCodec {
31    /// Create a new ReedSolomonCodec instance.
32    fn new(data_len: usize) -> Result<Self> {
33        Ok(Self {
34            data_len,
35            rs: ReedSolomon::new(data_len, data_len)?,
36        })
37    }
38}
39
40impl Codec for ReedSolomonCodec {
41    /// Encode encodes original data, automatically extracting share size.
42    /// There must be no missing shares. Only returns parity shares.
43    fn encode(&self, data: Matrix2D) -> Result<Matrix2D> {
44        let original_data_len = data.len();
45        let mut shards = vec![vec![0; self.data_len]; self.data_len];
46        for (i, row) in data.iter().enumerate() {
47            shards[i] = row.clone();
48        }
49        for _i in 0..data.len() {
50            shards.push(vec![0; data[0].len()])
51        }
52        self.rs.encode(&mut shards)?;
53        let encoded_data = shards[original_data_len..].to_vec();
54        Ok(encoded_data)
55    }
56
57    /// Decode sparse original + parity data, automatically extracting share size.
58    /// Missing shares must be nil. Returns original shares only.
59    fn decode(&self, _data: Matrix3D) -> Result<Matrix3D> {
60        todo!()
61    }
62
63    /// Return the max. number of chunks each code supports in a 2D square.
64    fn max_chunks(&self) -> usize {
65        REED_SOLOMON_MAX_CHUNKS
66    }
67}
rsmt2d_rs/codec.rs

rsmt2d_rs/
codec.rs
