rqbit/crates/librqbit/src/chunk_tracker.rs
2021-06-26 00:32:52 +01:00

71 lines
2.1 KiB
Rust

use log::{debug, info};
use crate::{
buffers::ByteString,
lengths::{Lengths, ValidPieceIndex},
peer_comms::Piece,
type_aliases::BF,
};
pub struct ChunkTracker {
needed_pieces: BF,
chunk_status: BF,
lengths: Lengths,
}
fn compute_chunk_status(lengths: &Lengths, needed_pieces: &BF) -> BF {
let required_bits = lengths.total_chunks();
let required_size = (required_bits as usize + 1) / 8;
let vec = vec![0u8; required_size];
let mut chunk_bf = BF::from_vec(vec);
for bit in needed_pieces.iter_zeros() {
let offset = bit * 8;
for i in 0..8 {
chunk_bf.set(offset + i, true);
}
}
chunk_bf
}
impl ChunkTracker {
pub fn new(needed_pieces: BF, lengths: Lengths) -> Self {
Self {
chunk_status: compute_chunk_status(&lengths, &needed_pieces),
needed_pieces,
lengths,
}
}
pub fn get_needed_pieces(&self) -> &BF {
&self.needed_pieces
}
pub fn reserve_needed_piece(&mut self, index: ValidPieceIndex) {
self.needed_pieces.set(index.get() as usize, false)
}
pub fn mark_piece_needed(&mut self, index: ValidPieceIndex) -> bool {
info!("remarking piece={} as needed", index);
self.needed_pieces.set(index.get() as usize, true);
self.chunk_status
.get_mut(self.lengths.chunk_range(index))
.map(|s| {
s.set_all(false);
true
})
.unwrap_or_default()
}
// return true if the whole piece is marked downloaded
pub fn mark_chunk_downloaded(&mut self, piece: &Piece<ByteString>) -> Option<bool> {
let chunk_info = self.lengths.chunk_info_from_received_piece(piece)?;
self.chunk_status
.set(chunk_info.absolute_index as usize, true);
let chunk_range = self.lengths.chunk_range(chunk_info.piece_index);
let chunk_range = self.chunk_status.get(chunk_range).unwrap();
let all = chunk_range.all();
debug!(
"piece={}, chunk_info={:?}, bits={:?}",
piece.index, chunk_info, chunk_range,
);
Some(all)
}
}