62 lines
1.3 KiB
Rust
62 lines
1.3 KiB
Rust
use std::{
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fs::File,
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io::{Read, Seek, SeekFrom},
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path::PathBuf,
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};
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use log::error;
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pub struct ChunkedFile<'t> {
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path: &'t PathBuf,
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cnum: u64,
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csize: usize,
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}
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impl<'t> ChunkedFile<'t> {
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pub(super) fn new(path: &'t PathBuf, chunk_size: usize) -> Self {
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Self {
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path,
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cnum: 0,
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csize: chunk_size,
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}
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}
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}
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impl Iterator for ChunkedFile<'_> {
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type Item = Chunk;
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fn next(&mut self) -> Option<Self::Item> {
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let offset = {
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let csize: u64 = self.csize.try_into().unwrap();
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self.cnum * csize
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};
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let mut f = File::open(self.path)
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.inspect_err(|e| error!("Error opening file: {e}"))
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.ok()?;
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f.seek(SeekFrom::Start(offset)).ok()?;
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let mut bytes = vec![0; self.csize];
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let read_len = f
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.read(&mut bytes)
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.inspect_err(|e| error!("Error reading file: {e}"))
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.ok()?;
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bytes.truncate(read_len);
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self.cnum += 1;
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Some(Self::Item { offset, bytes }).filter(|c| !c.bytes.is_empty())
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}
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}
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pub struct Chunk {
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pub offset: u64,
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pub bytes: Vec<u8>,
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}
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impl Chunk {
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pub fn after(&self) -> u64 {
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let len: u64 = self.bytes.len().try_into().unwrap();
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self.offset + len
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}
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}
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