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
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
|
package core
import (
"math"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/core/types"
"github.com/ethereum/go-ethereum/state"
)
type AccountChange struct {
Address, StateAddress []byte
}
type FilterOptions struct {
Earliest int64
Latest int64
Address []common.Address
Topics [][]common.Hash
Skip int
Max int
}
// Filtering interface
type Filter struct {
eth Backend
earliest int64
latest int64
skip int
address []common.Address
max int
topics [][]common.Hash
BlockCallback func(*types.Block, state.Logs)
PendingCallback func(*types.Block, state.Logs)
LogsCallback func(state.Logs)
}
// Create a new filter which uses a bloom filter on blocks to figure out whether a particular block
// is interesting or not.
func NewFilter(eth Backend) *Filter {
return &Filter{eth: eth}
}
// SetOptions copies the filter options to the filter it self. The reason for this "silly" copy
// is simply because named arguments in this case is extremely nice and readable.
func (self *Filter) SetOptions(options FilterOptions) {
self.earliest = options.Earliest
self.latest = options.Latest
self.skip = options.Skip
self.max = options.Max
self.address = options.Address
self.topics = options.Topics
}
// Set the earliest and latest block for filtering.
// -1 = latest block (i.e., the current block)
// hash = particular hash from-to
func (self *Filter) SetEarliestBlock(earliest int64) {
self.earliest = earliest
}
func (self *Filter) SetLatestBlock(latest int64) {
self.latest = latest
}
func (self *Filter) SetAddress(addr []common.Address) {
self.address = addr
}
func (self *Filter) SetTopics(topics [][]common.Hash) {
self.topics = topics
}
func (self *Filter) SetMax(max int) {
self.max = max
}
func (self *Filter) SetSkip(skip int) {
self.skip = skip
}
// Run filters logs with the current parameters set
func (self *Filter) Find() state.Logs {
earliestBlock := self.eth.ChainManager().CurrentBlock()
var earliestBlockNo uint64 = uint64(self.earliest)
if self.earliest == -1 {
earliestBlockNo = earliestBlock.NumberU64()
}
var latestBlockNo uint64 = uint64(self.latest)
if self.latest == -1 {
latestBlockNo = earliestBlock.NumberU64()
}
var (
logs state.Logs
block = self.eth.ChainManager().GetBlockByNumber(latestBlockNo)
quit bool
)
for i := 0; !quit && block != nil; i++ {
// Quit on latest
switch {
case block.NumberU64() == earliestBlockNo, block.NumberU64() == 0:
quit = true
case self.max <= len(logs):
break
}
// Use bloom filtering to see if this block is interesting given the
// current parameters
if self.bloomFilter(block) {
// Get the logs of the block
unfiltered, err := self.eth.BlockProcessor().GetLogs(block)
if err != nil {
chainlogger.Warnln("err: filter get logs ", err)
break
}
logs = append(logs, self.FilterLogs(unfiltered)...)
}
block = self.eth.ChainManager().GetBlock(block.ParentHash())
}
skip := int(math.Min(float64(len(logs)), float64(self.skip)))
return logs[skip:]
}
func includes(addresses []common.Address, a common.Address) bool {
for _, addr := range addresses {
if addr != a {
return false
}
}
return true
}
func (self *Filter) FilterLogs(logs state.Logs) state.Logs {
var ret state.Logs
// Filter the logs for interesting stuff
Logs:
for _, log := range logs {
if len(self.address) > 0 && !includes(self.address, log.Address()) {
continue
}
logTopics := make([]common.Hash, len(self.topics))
copy(logTopics, log.Topics())
for i, topics := range self.topics {
for _, topic := range topics {
var match bool
if log.Topics()[i] == topic {
match = true
}
if !match {
continue Logs
}
}
}
ret = append(ret, log)
}
return ret
}
func (self *Filter) bloomFilter(block *types.Block) bool {
if len(self.address) > 0 {
var included bool
for _, addr := range self.address {
if types.BloomLookup(block.Bloom(), addr.Hash()) {
included = true
break
}
}
if !included {
return false
}
}
for _, sub := range self.topics {
var included bool
for _, topic := range sub {
if types.BloomLookup(block.Bloom(), topic) {
included = true
break
}
}
if !included {
return false
}
}
return true
}
|
