1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64
// Copyright 2017-2020 Parity Technologies (UK) Ltd. // This file is part of Substrate. // Substrate 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. // Substrate 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 Substrate. If not, see <http://www.gnu.org/licenses/>. //! Primitives for Substrate Proof-of-Work (PoW) consensus. #![cfg_attr(not(feature = "std"), no_std)] use sp_std::vec::Vec; use sp_runtime::ConsensusEngineId; use codec::Decode; /// The `ConsensusEngineId` of PoW. pub const POW_ENGINE_ID: ConsensusEngineId = [b'p', b'o', b'w', b'_']; /// Type of seal. pub type Seal = Vec<u8>; /// Define methods that total difficulty should implement. pub trait TotalDifficulty { fn increment(&mut self, other: Self); } impl TotalDifficulty for sp_core::U256 { fn increment(&mut self, other: Self) { let ret = self.saturating_add(other); *self = ret; } } impl TotalDifficulty for u128 { fn increment(&mut self, other: Self) { let ret = self.saturating_add(other); *self = ret; } } sp_api::decl_runtime_apis! { /// API necessary for timestamp-based difficulty adjustment algorithms. pub trait TimestampApi<Moment: Decode> { /// Return the timestamp in the current block. fn timestamp() -> Moment; } /// API for those chains that put their difficulty adjustment algorithm directly /// onto runtime. Note that while putting difficulty adjustment algorithm to /// runtime is safe, putting the PoW algorithm on runtime is not. pub trait DifficultyApi<Difficulty: Decode> { /// Return the target difficulty of the next block. fn difficulty() -> Difficulty; } }