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extern crate common_types;
extern crate either;
extern crate vapory_types;
extern crate memmap;
extern crate parking_lot;
extern crate primal;
#[macro_use]
extern crate log;
#[macro_use]
extern crate static_assertions;
#[cfg(test)]
extern crate rustc_hex;
#[cfg(test)]
extern crate serde_json;
#[cfg(test)]
extern crate tempdir;
#[cfg(feature = "bench")]
pub mod compute;
#[cfg(not(feature = "bench"))]
mod compute;
mod seed_compute;
mod cache;
#[cfg(feature = "bench")]
pub mod keccak;
#[cfg(not(feature = "bench"))]
mod keccak;
mod shared;
#[cfg(feature = "bench")]
pub mod progpow;
#[cfg(not(feature = "bench"))]
mod progpow;
pub use cache::NodeCacheBuilder;
pub use compute::{ProofOfWork, quick_get_difficulty, slow_hash_block_number};
pub use seed_compute::SeedHashCompute;
pub use shared::VAPASH_EPOCH_LENGTH;
use common_types::engines::OptimizeFor;
use compute::Light;
use vapory_types::{BigEndianHash, U256, U512};
use keccak::H256;
use parking_lot::Mutex;
use std::mem;
use std::path::{Path, PathBuf};
use std::convert::TryFrom;
use std::sync::Arc;
struct LightCache {
recent_epoch: Option<u64>,
recent: Option<Arc<Light>>,
prev_epoch: Option<u64>,
prev: Option<Arc<Light>>,
}
pub struct VapashManager {
nodecache_builder: NodeCacheBuilder,
cache: Mutex<LightCache>,
cache_dir: PathBuf,
progpow_transition: u64,
}
impl VapashManager {
pub fn new<T: Into<Option<OptimizeFor>>>(cache_dir: &Path, optimize_for: T, progpow_transition: u64) -> VapashManager {
VapashManager {
cache_dir: cache_dir.to_path_buf(),
nodecache_builder: NodeCacheBuilder::new(optimize_for.into().unwrap_or_default(), progpow_transition),
progpow_transition,
cache: Mutex::new(LightCache {
recent_epoch: None,
recent: None,
prev_epoch: None,
prev: None,
}),
}
}
pub fn compute_light(&self, block_number: u64, header_hash: &H256, nonce: u64) -> ProofOfWork {
let epoch = block_number / VAPASH_EPOCH_LENGTH;
let light = {
let mut lights = self.cache.lock();
let light = if block_number == self.progpow_transition {
None
} else {
match lights.recent_epoch.clone() {
Some(ref e) if *e == epoch => lights.recent.clone(),
_ => match lights.prev_epoch.clone() {
Some(e) if e == epoch => {
if lights.recent_epoch > lights.prev_epoch {
None
} else {
let t = lights.prev_epoch;
lights.prev_epoch = lights.recent_epoch;
lights.recent_epoch = t;
let t = lights.prev.clone();
lights.prev = lights.recent.clone();
lights.recent = t;
lights.recent.clone()
}
}
_ => None,
},
}
};
match light {
None => {
let light = match self.nodecache_builder.light_from_file(
&self.cache_dir,
block_number,
) {
Ok(light) => Arc::new(light),
Err(e) => {
debug!("Light cache file not found for {}:{}", block_number, e);
let mut light = self.nodecache_builder.light(
&self.cache_dir,
block_number,
);
if let Err(e) = light.to_file() {
warn!("Light cache file write error: {}", e);
}
Arc::new(light)
}
};
lights.prev_epoch = mem::replace(&mut lights.recent_epoch, Some(epoch));
lights.prev = mem::replace(&mut lights.recent, Some(light.clone()));
light
}
Some(light) => light,
}
};
light.compute(header_hash, nonce, block_number)
}
}
pub fn boundary_to_difficulty(boundary: &vapory_types::H256) -> U256 {
difficulty_to_boundary_aux(&boundary.into_uint())
}
pub fn difficulty_to_boundary(difficulty: &U256) -> vapory_types::H256 {
BigEndianHash::from_uint(&difficulty_to_boundary_aux(difficulty))
}
fn difficulty_to_boundary_aux<T: Into<U512>>(difficulty: T) -> vapory_types::U256 {
let difficulty = difficulty.into();
assert!(!difficulty.is_zero());
if difficulty == U512::one() {
U256::max_value()
} else {
const PROOF: &str = "difficulty > 1, so result never overflows 256 bits; qed";
U256::try_from((U512::one() << 256) / difficulty).expect(PROOF)
}
}
#[test]
fn test_lru() {
use tempdir::TempDir;
let tempdir = TempDir::new("").unwrap();
let vapash = VapashManager::new(tempdir.path(), None, u64::max_value());
let hash = [0u8; 32];
vapash.compute_light(1, &hash, 1);
vapash.compute_light(50000, &hash, 1);
assert_eq!(vapash.cache.lock().recent_epoch.unwrap(), 1);
assert_eq!(vapash.cache.lock().prev_epoch.unwrap(), 0);
vapash.compute_light(1, &hash, 1);
assert_eq!(vapash.cache.lock().recent_epoch.unwrap(), 0);
assert_eq!(vapash.cache.lock().prev_epoch.unwrap(), 1);
vapash.compute_light(70000, &hash, 1);
assert_eq!(vapash.cache.lock().recent_epoch.unwrap(), 2);
assert_eq!(vapash.cache.lock().prev_epoch.unwrap(), 0);
}
#[test]
fn test_difficulty_to_boundary() {
use vapory_types::{H256, BigEndianHash};
use std::str::FromStr;
assert_eq!(difficulty_to_boundary(&U256::from(1)), BigEndianHash::from_uint(&U256::max_value()));
assert_eq!(difficulty_to_boundary(&U256::from(2)), H256::from_str("8000000000000000000000000000000000000000000000000000000000000000").unwrap());
assert_eq!(difficulty_to_boundary(&U256::from(4)), H256::from_str("4000000000000000000000000000000000000000000000000000000000000000").unwrap());
assert_eq!(difficulty_to_boundary(&U256::from(32)), H256::from_str("0800000000000000000000000000000000000000000000000000000000000000").unwrap());
}
#[test]
fn test_difficulty_to_boundary_regression() {
use vapory_types::H256;
for difficulty in 1..9 {
assert_eq!(U256::from(difficulty), boundary_to_difficulty(&difficulty_to_boundary(&difficulty.into())));
assert_eq!(
H256::from_low_u64_be(difficulty),
difficulty_to_boundary(&boundary_to_difficulty(&H256::from_low_u64_be(difficulty))),
);
assert_eq!(
U256::from(difficulty),
boundary_to_difficulty(&BigEndianHash::from_uint(&boundary_to_difficulty(&H256::from_low_u64_be(difficulty)))),
);
assert_eq!(
H256::from_low_u64_be(difficulty),
difficulty_to_boundary(&difficulty_to_boundary(&difficulty.into()).into_uint()),
);
}
}
#[test]
#[should_panic]
fn test_difficulty_to_boundary_panics_on_zero() {
difficulty_to_boundary(&U256::from(0));
}
#[test]
#[should_panic]
fn test_boundary_to_difficulty_panics_on_zero() {
boundary_to_difficulty(&vapory_types::H256::zero());
}