impl insert_chunk

This commit is contained in:
Dietmar Maurer 2018-12-07 14:44:56 +01:00
parent 91a597cc08
commit 128b37feea

View File

@ -1,18 +1,47 @@
use failure::*;
use std::path::{Path, PathBuf};
use std::io::Write;
use crypto::digest::Digest;
use crypto::sha2::Sha512Trunc256;
pub struct ChunkStore {
base: PathBuf,
chunk_dir: PathBuf,
hasher: Sha512Trunc256,
}
// see RFC4648 for base32hex definition
const BASE32HEX_ALPHABET: &'static [u8; 32] = b"0123456789ABCDEFGHIJKLMNOPQRSTUV";
const HEX_CHARS: &'static [u8; 16] = b"0123456789abcdef";
fn u10_to_base32hex(num: usize) -> String {
let lo = num & 0b11111 as usize;
let hi = num >> 5 as usize;
format!("{}{}", BASE32HEX_ALPHABET[hi] as char, BASE32HEX_ALPHABET[lo] as char)
fn u256_to_hex(digest: &[u8; 32]) -> String {
let mut buf = Vec::<u8>::with_capacity(64);
for i in 0..32 {
buf.push(HEX_CHARS[(digest[i] >> 4) as usize]);
buf.push(HEX_CHARS[(digest[i] & 0xf) as usize]);
}
unsafe { String::from_utf8_unchecked(buf) }
}
fn u256_to_prefix(digest: &[u8; 32]) -> PathBuf {
let mut buf = Vec::<u8>::with_capacity(3+1+2+1);
buf.push(HEX_CHARS[(digest[0] as usize) >> 4]);
buf.push(HEX_CHARS[(digest[0] as usize) &0xf]);
buf.push(HEX_CHARS[(digest[1] as usize) >> 4]);
buf.push('/' as u8);
buf.push(HEX_CHARS[(digest[1] as usize) & 0xf]);
buf.push(HEX_CHARS[(digest[2] as usize) >> 4]);
buf.push('/' as u8);
let path = unsafe { String::from_utf8_unchecked(buf)};
path.into()
}
impl ChunkStore {
@ -22,7 +51,9 @@ impl ChunkStore {
let mut chunk_dir = base.clone();
chunk_dir.push(".chunks");
ChunkStore { base, chunk_dir }
let hasher = Sha512Trunc256::new();
ChunkStore { base, chunk_dir, hasher }
}
pub fn create<P: Into<PathBuf>>(path: P) -> Result<Self, Error> {
@ -32,10 +63,10 @@ impl ChunkStore {
std::fs::create_dir(&me.base)?;
std::fs::create_dir(&me.chunk_dir)?;
// create 1024 subdir
for i in 0..1024 {
// create 4096 subdir
for i in 0..4096 {
let mut l1path = me.base.clone();
l1path.push(u10_to_base32hex(i));
l1path.push(format!("{:03x}",i));
std::fs::create_dir(&l1path)?;
}
@ -53,6 +84,35 @@ impl ChunkStore {
Ok(me)
}
pub fn insert_chunk(&mut self, chunk: &[u8]) -> Result<([u8; 32]), Error> {
self.hasher.reset();
self.hasher.input(chunk);
let mut digest = [0u8; 32];
self.hasher.result(&mut digest);
println!("DIGEST {}", u256_to_hex(&digest));
let mut chunk_path = self.base.clone();
let prefix = u256_to_prefix(&digest);
chunk_path.push(prefix);
if let Err(_e) = std::fs::create_dir(&chunk_path) { /* ignore */ }
println!("PATH {:?}", chunk_path);
chunk_path.push(u256_to_hex(&digest));
//chunk_path.set_extension("tmp");
//chunk_path.set_extension("");
let mut f = std::fs::File::create(&chunk_path)?;
f.write_all(chunk)?;
println!("PATH {:?}", chunk_path);
Ok(digest)
}
}
@ -64,8 +124,9 @@ fn test_chunk_store1() {
let chunk_store = ChunkStore::open(".testdir");
assert!(chunk_store.is_err());
let chunk_store = ChunkStore::create(".testdir");
assert!(chunk_store.is_ok());
let mut chunk_store = ChunkStore::create(".testdir").unwrap();
chunk_store.insert_chunk(&[0u8, 1u8]);
let chunk_store = ChunkStore::create(".testdir");
assert!(chunk_store.is_err());