src/backup/fixed_index.rs: new helper to compute checksum and file size

This commit is contained in:
Dietmar Maurer 2019-09-03 13:11:45 +02:00
parent 82c85a21a1
commit 0a51fe0011

View File

@ -1,5 +1,6 @@
use failure::*;
use std::io::{Seek, SeekFrom};
use std::convert::TryInto;
use crate::tools;
use super::IndexFile;
@ -166,6 +167,15 @@ impl FixedIndexReader {
Ok((start, end, unsafe { digest.assume_init() }))
}
#[inline]
fn chunk_digest(&self, pos: usize) -> &[u8; 32] {
if pos >= self.index_length {
panic!("chunk index out of range");
}
let slice = unsafe { std::slice::from_raw_parts(self.index.add(pos*32), 32) };
slice.try_into().unwrap()
}
#[inline]
fn chunk_end(&self, pos: usize) -> u64 {
if pos >= self.index_length {
@ -180,6 +190,22 @@ impl FixedIndexReader {
}
}
/// Compute checksum and data size
pub fn compute_csum(&self) -> ([u8; 32], u64) {
let mut csum = openssl::sha::Sha256::new();
let mut chunk_end = 0;
for pos in 0..self.index_length {
chunk_end = ((pos+1) * self.chunk_size) as u64;
let digest = self.chunk_digest(pos);
csum.update(&chunk_end.to_le_bytes());
csum.update(digest);
}
let csum = csum.finish();
(csum, chunk_end)
}
pub fn print_info(&self) {
println!("Size: {}", self.size);
println!("ChunkSize: {}", self.chunk_size);