openethereum/ethstore/src/json/hash.rs
2017-07-06 11:36:15 +02:00

120 lines
3.1 KiB
Rust

// Copyright 2015-2017 Parity Technologies (UK) Ltd.
// This file is part of Parity.
// Parity is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// Parity is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with Parity. If not, see <http://www.gnu.org/licenses/>.
use std::{ops, fmt, str};
use rustc_hex::{FromHex, ToHex};
use serde::{Serialize, Serializer, Deserialize, Deserializer};
use serde::de::{Visitor, Error as SerdeError};
use super::Error;
macro_rules! impl_hash {
($name: ident, $size: expr) => {
pub struct $name([u8; $size]);
impl fmt::Debug for $name {
fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
let self_ref: &[u8] = &self.0;
write!(f, "{:?}", self_ref)
}
}
impl PartialEq for $name {
fn eq(&self, other: &Self) -> bool {
let self_ref: &[u8] = &self.0;
let other_ref: &[u8] = &other.0;
self_ref == other_ref
}
}
impl ops::Deref for $name {
type Target = [u8];
fn deref(&self) -> &Self::Target {
&self.0
}
}
impl Serialize for $name {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where S: Serializer {
serializer.serialize_str(&self.0.to_hex())
}
}
impl<'a> Deserialize<'a> for $name {
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where D: Deserializer<'a> {
struct HashVisitor;
impl<'b> Visitor<'b> for HashVisitor {
type Value = $name;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
write!(formatter, "a hex-encoded {}", stringify!($name))
}
fn visit_str<E>(self, value: &str) -> Result<Self::Value, E> where E: SerdeError {
value.parse().map_err(SerdeError::custom)
}
fn visit_string<E>(self, value: String) -> Result<Self::Value, E> where E: SerdeError {
self.visit_str(value.as_ref())
}
}
deserializer.deserialize_any(HashVisitor)
}
}
impl str::FromStr for $name {
type Err = Error;
fn from_str(value: &str) -> Result<Self, Self::Err> {
match value.from_hex() {
Ok(ref hex) if hex.len() == $size => {
let mut hash = [0u8; $size];
hash.clone_from_slice(hex);
Ok($name(hash))
}
_ => Err(Error::InvalidH256),
}
}
}
impl From<&'static str> for $name {
fn from(s: &'static str) -> Self {
s.parse().expect(&format!("invalid string literal for {}: '{}'", stringify!($name), s))
}
}
impl From<[u8; $size]> for $name {
fn from(bytes: [u8; $size]) -> Self {
$name(bytes)
}
}
impl Into<[u8; $size]> for $name {
fn into(self) -> [u8; $size] {
self.0
}
}
}
}
impl_hash!(H128, 16);
impl_hash!(H160, 20);
impl_hash!(H256, 32);