openethereum/util/src/error.rs
2017-07-29 22:49:10 +02:00

165 lines
4.8 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/>.
//! General error types for use in ethcore.
use rustc_hex::FromHexError;
use rlp::DecoderError;
use std::fmt;
use bigint::hash::H256;
#[derive(Debug)]
/// Error in database subsystem.
pub enum BaseDataError {
/// An entry was removed more times than inserted.
NegativelyReferencedHash(H256),
/// A committed value was inserted more than once.
AlreadyExists(H256),
}
impl fmt::Display for BaseDataError {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
match *self {
BaseDataError::NegativelyReferencedHash(hash) =>
write!(f, "Entry {} removed from database more times than it was added.", hash),
BaseDataError::AlreadyExists(hash) =>
write!(f, "Committed key already exists in database: {}", hash),
}
}
}
#[derive(Debug)]
/// General error type which should be capable of representing all errors in ethcore.
pub enum UtilError {
/// Error concerning the Rust standard library's IO subsystem.
StdIo(::std::io::Error),
/// Error concerning the hex conversion logic.
FromHex(FromHexError),
/// Error concerning the database abstraction logic.
BaseData(BaseDataError),
/// Error concerning the RLP decoder.
Decoder(DecoderError),
/// Miscellaneous error described by a string.
SimpleString(String),
/// Error from a bad input size being given for the needed output.
BadSize,
/// Error from snappy.
Snappy(::snappy::InvalidInput),
}
impl fmt::Display for UtilError {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
match *self {
UtilError::StdIo(ref err) => f.write_fmt(format_args!("{}", err)),
UtilError::FromHex(ref err) => f.write_fmt(format_args!("{}", err)),
UtilError::BaseData(ref err) => f.write_fmt(format_args!("{}", err)),
UtilError::Decoder(ref err) => f.write_fmt(format_args!("{}", err)),
UtilError::SimpleString(ref msg) => f.write_str(msg),
UtilError::BadSize => f.write_str("Bad input size."),
UtilError::Snappy(ref err) => f.write_fmt(format_args!("{}", err)),
}
}
}
#[derive(Debug, PartialEq, Eq, Clone, Copy)]
/// Error indicating an expected value was not found.
pub struct Mismatch<T: fmt::Debug> {
/// Value expected.
pub expected: T,
/// Value found.
pub found: T,
}
impl<T: fmt::Debug + fmt::Display> fmt::Display for Mismatch<T> {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
f.write_fmt(format_args!("Expected {}, found {}", self.expected, self.found))
}
}
#[derive(Debug, PartialEq, Eq, Clone, Copy)]
/// Error indicating value found is outside of a valid range.
pub struct OutOfBounds<T: fmt::Debug> {
/// Minimum allowed value.
pub min: Option<T>,
/// Maximum allowed value.
pub max: Option<T>,
/// Value found.
pub found: T,
}
impl<T: fmt::Debug + fmt::Display> fmt::Display for OutOfBounds<T> {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
let msg = match (self.min.as_ref(), self.max.as_ref()) {
(Some(min), Some(max)) => format!("Min={}, Max={}", min, max),
(Some(min), _) => format!("Min={}", min),
(_, Some(max)) => format!("Max={}", max),
(None, None) => "".into(),
};
f.write_fmt(format_args!("Value {} out of bounds. {}", self.found, msg))
}
}
impl From<FromHexError> for UtilError {
fn from(err: FromHexError) -> UtilError {
UtilError::FromHex(err)
}
}
impl From<BaseDataError> for UtilError {
fn from(err: BaseDataError) -> UtilError {
UtilError::BaseData(err)
}
}
impl From<::std::io::Error> for UtilError {
fn from(err: ::std::io::Error) -> UtilError {
UtilError::StdIo(err)
}
}
impl From<::rlp::DecoderError> for UtilError {
fn from(err: ::rlp::DecoderError) -> UtilError {
UtilError::Decoder(err)
}
}
impl From<String> for UtilError {
fn from(err: String) -> UtilError {
UtilError::SimpleString(err)
}
}
impl From<::snappy::InvalidInput> for UtilError {
fn from(err: ::snappy::InvalidInput) -> UtilError {
UtilError::Snappy(err)
}
}
// TODO: uncomment below once https://github.com/rust-lang/rust/issues/27336 sorted.
/*#![feature(concat_idents)]
macro_rules! assimilate {
($name:ident) => (
impl From<concat_idents!($name, Error)> for Error {
fn from(err: concat_idents!($name, Error)) -> Error {
Error:: $name (err)
}
}
)
}
assimilate!(FromHex);
assimilate!(BaseData);*/