core, consensus: pluggable consensus engines (#3817)

This commit adds pluggable consensus engines to go-ethereum. In short, it
introduces a generic consensus interface, and refactors the entire codebase to
use this interface.

1 files changed, 0 insertions, 57 deletions

diff --git a/pow/ethash_algo_go1.8.go b/pow/ethash_algo_go1.8.go
deleted file mode 100644
index cac96cd5e..000000000
--- a/pow/ethash_algo_go1.8.go
+++ /dev/null
@@ -1,57 +0,0 @@
-// Copyright 2017 The go-ethereum Authors
-// This file is part of the go-ethereum library.
-//
-// The go-ethereum library is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// The go-ethereum library 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 Lesser General Public License for more details.
-//
-// You should have received a copy of the GNU Lesser General Public License
-// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
-
-// +build go1.8
-
-package pow
-
-import "math/big"
-
-// cacheSize calculates and returns the size of the ethash verification cache that
-// belongs to a certain block number. The cache size grows linearly, however, we
-// always take the highest prime below the linearly growing threshold in order to
-// reduce the risk of accidental regularities leading to cyclic behavior.
-func cacheSize(block uint64) uint64 {
-	// If we have a pre-generated value, use that
-	epoch := int(block / epochLength)
-	if epoch < len(cacheSizes) {
-		return cacheSizes[epoch]
-	}
-	// No known cache size, calculate manually (sanity branch only)
-	size := uint64(cacheInitBytes + cacheGrowthBytes*uint64(epoch) - hashBytes)
-	for !new(big.Int).SetUint64(size / hashBytes).ProbablyPrime(1) { // Always accurate for n < 2^64
-		size -= 2 * hashBytes
-	}
-	return size
-}
-
-// datasetSize calculates and returns the size of the ethash mining dataset that
-// belongs to a certain block number. The dataset size grows linearly, however, we
-// always take the highest prime below the linearly growing threshold in order to
-// reduce the risk of accidental regularities leading to cyclic behavior.
-func datasetSize(block uint64) uint64 {
-	// If we have a pre-generated value, use that
-	epoch := int(block / epochLength)
-	if epoch < len(datasetSizes) {
-		return datasetSizes[epoch]
-	}
-	// No known dataset size, calculate manually (sanity branch only)
-	size := uint64(datasetInitBytes + datasetGrowthBytes*uint64(epoch) - mixBytes)
-	for !new(big.Int).SetUint64(size / mixBytes).ProbablyPrime(1) { // Always accurate for n < 2^64
-		size -= 2 * mixBytes
-	}
-	return size
-}