les: duplicate downloader and fetcher to allow progressive refactoring

les/downloader/types.go

@@ -0,0 +1,79 @@
+// Copyright 2015 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 downloader
+
+import (
+	"fmt"
+
+	"github.com/ethereum/go-ethereum/core/types"
+)
+
+// peerDropFn is a callback type for dropping a peer detected as malicious.
+type peerDropFn func(id string)
+
+// dataPack is a data message returned by a peer for some query.
+type dataPack interface {
+	PeerId() string
+	Items() int
+	Stats() string
+}
+
+// headerPack is a batch of block headers returned by a peer.
+type headerPack struct {
+	peerID  string
+	headers []*types.Header
+}
+
+func (p *headerPack) PeerId() string { return p.peerID }
+func (p *headerPack) Items() int     { return len(p.headers) }
+func (p *headerPack) Stats() string  { return fmt.Sprintf("%d", len(p.headers)) }
+
+// bodyPack is a batch of block bodies returned by a peer.
+type bodyPack struct {
+	peerID       string
+	transactions [][]*types.Transaction
+	uncles       [][]*types.Header
+}
+
+func (p *bodyPack) PeerId() string { return p.peerID }
+func (p *bodyPack) Items() int {
+	if len(p.transactions) <= len(p.uncles) {
+		return len(p.transactions)
+	}
+	return len(p.uncles)
+}
+func (p *bodyPack) Stats() string { return fmt.Sprintf("%d:%d", len(p.transactions), len(p.uncles)) }
+
+// receiptPack is a batch of receipts returned by a peer.
+type receiptPack struct {
+	peerID   string
+	receipts [][]*types.Receipt
+}
+
+func (p *receiptPack) PeerId() string { return p.peerID }
+func (p *receiptPack) Items() int     { return len(p.receipts) }
+func (p *receiptPack) Stats() string  { return fmt.Sprintf("%d", len(p.receipts)) }
+
+// statePack is a batch of states returned by a peer.
+type statePack struct {
+	peerID string
+	states [][]byte
+}
+
+func (p *statePack) PeerId() string { return p.peerID }
+func (p *statePack) Items() int     { return len(p.states) }
+func (p *statePack) Stats() string  { return fmt.Sprintf("%d", len(p.states)) }