119 lines
		
	
	
		
			4.3 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
			
		
		
	
	
			119 lines
		
	
	
		
			4.3 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
// 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)
 | 
						|
		}
 | 
						|
	}
 | 
						|
}
 |