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Diffstat (limited to 'miner/unconfirmed.go')
-rw-r--r-- | miner/unconfirmed.go | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/miner/unconfirmed.go b/miner/unconfirmed.go new file mode 100644 index 000000000..86a30de35 --- /dev/null +++ b/miner/unconfirmed.go @@ -0,0 +1,118 @@ +// Copyright 2016 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/>. + +package miner + +import ( + "container/ring" + "sync" + + "github.com/ethereum/go-ethereum/common" + "github.com/ethereum/go-ethereum/core/types" + "github.com/ethereum/go-ethereum/logger" + "github.com/ethereum/go-ethereum/logger/glog" +) + +// headerRetriever is used by the unconfirmed block set to verify whether a previously +// mined block is part of the canonical chain or not. +type headerRetriever interface { + // GetHeaderByNumber retrieves the canonical header associated with a block number. + GetHeaderByNumber(number uint64) *types.Header +} + +// unconfirmedBlock is a small collection of metadata about a locally mined block +// that is placed into a unconfirmed set for canonical chain inclusion tracking. +type unconfirmedBlock struct { + index uint64 + hash common.Hash +} + +// unconfirmedBlocks implements a data structure to maintain locally mined blocks +// have have not yet reached enough maturity to guarantee chain inclusion. It is +// used by the miner to provide logs to the user when a previously mined block +// has a high enough guarantee to not be reorged out of te canonical chain. +type unconfirmedBlocks struct { + chain headerRetriever // Blockchain to verify canonical status through + depth uint // Depth after which to discard previous blocks + blocks *ring.Ring // Block infos to allow canonical chain cross checks + lock sync.RWMutex // Protects the fields from concurrent access +} + +// newUnconfirmedBlocks returns new data structure to track currently unconfirmed blocks. +func newUnconfirmedBlocks(chain headerRetriever, depth uint) *unconfirmedBlocks { + return &unconfirmedBlocks{ + chain: chain, + depth: depth, + } +} + +// Insert adds a new block to the set of unconfirmed ones. +func (set *unconfirmedBlocks) Insert(index uint64, hash common.Hash) { + // If a new block was mined locally, shift out any old enough blocks + set.Shift(index) + + // Create the new item as its own ring + item := ring.New(1) + item.Value = &unconfirmedBlock{ + index: index, + hash: hash, + } + // Set as the initial ring or append to the end + set.lock.Lock() + defer set.lock.Unlock() + + if set.blocks == nil { + set.blocks = item + } else { + set.blocks.Move(-1).Link(item) + } + // Display a log for the user to notify of a new mined block unconfirmed + glog.V(logger.Info).Infof("🔨 mined potential block #%d [%x…], waiting for %d blocks to confirm", index, hash.Bytes()[:4], set.depth) +} + +// Shift drops all unconfirmed blocks from the set which exceed the unconfirmed sets depth +// allowance, checking them against the canonical chain for inclusion or staleness +// report. +func (set *unconfirmedBlocks) Shift(height uint64) { + set.lock.Lock() + defer set.lock.Unlock() + + for set.blocks != nil { + // Retrieve the next unconfirmed block and abort if too fresh + next := set.blocks.Value.(*unconfirmedBlock) + if next.index+uint64(set.depth) > height { + break + } + // Block seems to exceed depth allowance, check for canonical status + header := set.chain.GetHeaderByNumber(next.index) + switch { + case header == nil: + glog.V(logger.Warn).Infof("failed to retrieve header of mined block #%d [%x…]", next.index, next.hash.Bytes()[:4]) + case header.Hash() == next.hash: + glog.V(logger.Info).Infof("🔗 mined block #%d [%x…] reached canonical chain", next.index, next.hash.Bytes()[:4]) + default: + glog.V(logger.Info).Infof("⑂ mined block #%d [%x…] became a side fork", next.index, next.hash.Bytes()[:4]) + } + // Drop the block out of the ring + if set.blocks.Value == set.blocks.Next().Value { + set.blocks = nil + } else { + set.blocks = set.blocks.Move(-1) + set.blocks.Unlink(1) + set.blocks = set.blocks.Move(1) + } + } +} |