mirror of
https://gitlab.com/pulsechaincom/erigon-pulse.git
synced 2024-12-25 21:17:16 +00:00
96 lines
3.3 KiB
Go
96 lines
3.3 KiB
Go
// Copyright 2019 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 off
|
|
// 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 trie
|
|
|
|
import (
|
|
"bytes"
|
|
"sort"
|
|
)
|
|
|
|
// ResolveSet encapsulates the set of keys that are required to be fully available, or resolved
|
|
// (by using `BRANCH` opcode instead of `HASHER`) after processing of the sequence of key-value
|
|
// pairs
|
|
// DESCRIBED: docs/programmers_guide/guide.md#converting-sequence-of-keys-and-value-into-a-multiproof
|
|
type ResolveSet struct {
|
|
minLength int // Mininum length of prefixes for which `HashOnly` function can return `true`
|
|
hexes sortable
|
|
inited bool // Whether keys are sorted and "LTE" and "GT" indices set
|
|
lteIndex int // Index of the "LTE" key in the keys slice. Next one is "GT"
|
|
}
|
|
|
|
// NewResolveSet creates new ResolveSet
|
|
func NewResolveSet(minLength int) *ResolveSet {
|
|
return &ResolveSet{minLength: minLength}
|
|
}
|
|
|
|
// AddKey adds a new key (in KEY encoding) to the set
|
|
func (rs *ResolveSet) AddKey(key []byte) {
|
|
rs.hexes = append(rs.hexes, keybytesToHex(key))
|
|
}
|
|
|
|
// AddHex adds a new key (in HEX encoding) to the set
|
|
func (rs *ResolveSet) AddHex(hex []byte) {
|
|
rs.hexes = append(rs.hexes, hex)
|
|
}
|
|
|
|
func (rs *ResolveSet) ensureInited() {
|
|
if rs.inited {
|
|
return
|
|
}
|
|
if !sort.IsSorted(rs.hexes) {
|
|
sort.Sort(rs.hexes)
|
|
}
|
|
rs.lteIndex = 0
|
|
rs.inited = true
|
|
}
|
|
|
|
// HashOnly decides whether to emit `HASHER` or `BRANCH` for a given prefix, by
|
|
// checking if this is prefix of any of the keys added to the set
|
|
// Since keys in the set are sorted, and we expect that the prefixes will
|
|
// come in monotonically ascending order, we optimise for this, though
|
|
// the function would still work if the order is different
|
|
func (rs *ResolveSet) HashOnly(prefix []byte) bool {
|
|
rs.ensureInited()
|
|
if len(prefix) < rs.minLength {
|
|
return false
|
|
}
|
|
// Adjust "GT" if necessary
|
|
var gtAdjusted bool
|
|
for rs.lteIndex < len(rs.hexes)-1 && bytes.Compare(rs.hexes[rs.lteIndex+1], prefix) <= 0 {
|
|
rs.lteIndex++
|
|
gtAdjusted = true
|
|
}
|
|
// Adjust "LTE" if necessary (normally will not be necessary)
|
|
for !gtAdjusted && rs.lteIndex > 0 && bytes.Compare(rs.hexes[rs.lteIndex], prefix) > 0 {
|
|
rs.lteIndex--
|
|
}
|
|
if rs.lteIndex < len(rs.hexes) && bytes.HasPrefix(rs.hexes[rs.lteIndex], prefix) {
|
|
return false
|
|
}
|
|
if rs.lteIndex < len(rs.hexes)-1 && bytes.HasPrefix(rs.hexes[rs.lteIndex+1], prefix) {
|
|
return false
|
|
}
|
|
return true
|
|
}
|
|
|
|
// Current returns the hex value that has been used for the latest comparison in `HashOnly` function
|
|
// It is only used in one edge case at the moment - to distinguish between the accounts' key
|
|
// and the storage keys of the same account
|
|
func (rs *ResolveSet) Current() []byte {
|
|
return rs.hexes[rs.lteIndex]
|
|
}
|