forked from ledgerwatch/erigon
-
Notifications
You must be signed in to change notification settings - Fork 0
/
rolling_finality.go
172 lines (158 loc) · 4.96 KB
/
rolling_finality.go
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
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
// 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/>.
package aura
import (
"container/list"
"fmt"
libcommon "github.com/nebojsa94/erigon/erigon-lib/common"
)
// RollingFinality checker for authority round consensus.
// Stores a chain of unfinalized hashes that can be pushed onto.
// nolint
type RollingFinality struct {
headers unAssembledHeaders //nolint
signers *SimpleList
signCount map[libcommon.Address]uint
lastPushed *libcommon.Hash // Option<H256>,
}
// NewRollingFinality creates a blank finality checker under the given validator set.
func NewRollingFinality(signers []libcommon.Address) *RollingFinality {
return &RollingFinality{
signers: NewSimpleList(signers),
headers: unAssembledHeaders{l: list.New()},
signCount: map[libcommon.Address]uint{},
}
}
// Clears the finality status, but keeps the validator set.
func (f *RollingFinality) print(num uint64) {
if num > DEBUG_LOG_FROM {
h := f.headers
fmt.Printf("finality_heads: %d\n", num)
i := 0
for e := h.l.Front(); e != nil; e = e.Next() {
i++
a := e.Value.(*unAssembledHeader)
fmt.Printf("\t%d,%x\n", a.number, a.signers[0])
}
if i == 0 {
fmt.Printf("\tempty\n")
}
}
}
func (f *RollingFinality) clear() {
f.headers = unAssembledHeaders{l: list.New()}
f.signCount = map[libcommon.Address]uint{}
f.lastPushed = nil
}
// Push a hash onto the rolling finality checker (implying `subchain_head` == head.parent)
//
// Fails if `signer` isn't a member of the active validator set.
// Returns a list of all newly finalized headers.
func (f *RollingFinality) push(head libcommon.Hash, num uint64, signers []libcommon.Address) (newlyFinalized []unAssembledHeader, err error) {
for i := range signers {
if !f.hasSigner(signers[i]) {
return nil, fmt.Errorf("unknown validator")
}
}
f.addSigners(signers)
f.headers.PushBack(&unAssembledHeader{hash: head, number: num, signers: signers})
for f.isFinalized() {
e := f.headers.Pop()
if e == nil {
panic("headers length always greater than sign count length")
}
f.removeSigners(e.signers)
newlyFinalized = append(newlyFinalized, *e)
}
f.lastPushed = &head
return newlyFinalized, nil
}
// isFinalized returns whether the first entry in `self.headers` is finalized.
func (f *RollingFinality) isFinalized() bool {
e := f.headers.Front()
if e == nil {
return false
}
return len(f.signCount)*2 > len(f.signers.validators)
}
func (f *RollingFinality) hasSigner(signer libcommon.Address) bool {
for j := range f.signers.validators {
if f.signers.validators[j] == signer {
return true
}
}
return false
}
func (f *RollingFinality) addSigners(signers []libcommon.Address) bool {
for i := range signers {
count, ok := f.signCount[signers[i]]
if ok {
f.signCount[signers[i]] = count + 1
} else {
f.signCount[signers[i]] = 1
}
}
return false
}
func (f *RollingFinality) removeSigners(signers []libcommon.Address) {
for i := range signers {
count, ok := f.signCount[signers[i]]
if !ok {
panic("all hashes in `header` should have entries in `sign_count` for their signers")
//continue
}
if count <= 1 {
delete(f.signCount, signers[i])
} else {
f.signCount[signers[i]] = count - 1
}
}
}
func (f *RollingFinality) buildAncestrySubChain(get func(hash libcommon.Hash) ([]libcommon.Address, libcommon.Hash, libcommon.Hash, uint64, bool), parentHash, epochTransitionHash libcommon.Hash) error { // starts from chainHeadParentHash
f.clear()
for {
signers, blockHash, newParentHash, blockNum, ok := get(parentHash)
if !ok {
return nil
}
if blockHash == epochTransitionHash {
return nil
}
for i := range signers {
if !f.hasSigner(signers[i]) {
return fmt.Errorf("unknown validator: blockNum=%d", blockNum)
}
}
if f.lastPushed == nil {
copyHash := parentHash
f.lastPushed = ©Hash
}
f.addSigners(signers)
f.headers.PushFront(&unAssembledHeader{hash: blockHash, number: blockNum, signers: signers})
// break when we've got our first finalized block.
if f.isFinalized() {
e := f.headers.Pop()
if e == nil {
panic("we just pushed a block")
}
f.removeSigners(e.signers)
//log.Info("[aura] finality encountered already finalized block", "hash", e.hash.String(), "number", e.number)
break
}
parentHash = newParentHash
}
return nil
}