erigon-pulse/trie/structural_2.go

477 lines
14 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"
"fmt"
"math/bits"
"github.com/ledgerwatch/turbo-geth/common"
"github.com/ledgerwatch/turbo-geth/common/pool"
"github.com/valyala/bytebufferpool"
"golang.org/x/crypto/sha3"
)
// Experimental code for separating data and structural information
// Each function corresponds to an opcode
// DESCRIBED: docs/programmers_guide/guide.md#separation-of-keys-and-the-structure
type structInfoReceiver interface {
leaf(length int)
leafHash(length int)
extension(key []byte)
extensionHash(key []byte)
branch(set uint32)
branchHash(set uint32)
hash(number int)
}
// genStructStep is one step of the algorithm that generates the structural information based on the sequence of keys.
// `hashOnly` parameter is the function that, called for a certain prefix, determines whether the trie node for that prefix needs to be
// compressed into just hash (if `true` is returned), or constructed (if `false` is returned). Usually the `hashOnly` function is
// implemented in such a way to guarantee that certain keys are always accessible in the resulting trie (see ResolveSet.HashOnly function).
// `recursive` parameter is set to true if the algorithm's step is invoked recursively, i.e. not after a freshly provided leaf.
// Recursive invocation is used to emit opcodes for non-leaf nodes.
// `prec`, `curr`, `succ` are three full keys or prefixes that are currently visible to the algorithm. By comparing these, the algorithm
// makes decisions about the local structure, i.e. the presense of the prefix groups.
// `e` parameter is a `structInfoReceiver`, an object that receives opcode messages.
// `groups` parameter is the map of the stack. each element of the `groups` slice is a bitmask, one bit per element currently on the stack.
// Whenever a `BRANCH` or `BRANCHHASH` opcode is emitted, the set of digits is taken from the corresponding `groups` item, which is
// then removed from the slice. This signifies the usage of the number of the stack items by the `BRANCH` or `BRANCHHASH` opcode.
// DESCRIBED: docs/programmers_guide/guide.md#separation-of-keys-and-the-structure
func genStructStep(
hashOnly func(prefix []byte) bool,
recursive bool,
prec, curr, succ []byte,
e structInfoReceiver,
groups []uint32,
) []uint32 {
if !recursive && len(prec) == 0 {
prec = nil
}
// Calculate the prefix of the smallest prefix group containing curr
precLen := prefixLen(prec, curr)
succLen := prefixLen(succ, curr)
var maxLen int
if precLen > succLen {
maxLen = precLen
} else {
maxLen = succLen
}
//fmt.Printf("prec: %x, curr: %x, succ: %x, maxLen %d, prefix: %x\n", prec, curr, succ, maxLen, prefix)
// Add the digit immediately following the max common prefix and compute length of remainder length
extraDigit := curr[maxLen]
for maxLen >= len(groups) {
groups = append(groups, 0)
}
groups[maxLen] |= (uint32(1) << extraDigit)
//fmt.Printf("groups[%d] is now %b, len(groups) %d, prefix %x\n", maxLen, groups[maxLen], len(groups), prefix)
remainderStart := maxLen
if len(succ) > 0 || prec != nil {
remainderStart++
}
remainderLen := len(curr) - remainderStart
// Emit LEAF or EXTENSION based on the remainder
if recursive {
if remainderLen > 0 {
if hashOnly(curr[:maxLen]) {
e.extensionHash(curr[remainderStart : remainderStart+remainderLen])
} else {
e.extension(curr[remainderStart : remainderStart+remainderLen])
}
}
} else {
if hashOnly(curr[:maxLen]) {
e.leafHash(remainderLen)
} else {
e.leaf(remainderLen)
}
}
// Check for the optional part
if precLen <= succLen && len(succ) > 0 {
return groups
}
// Close the immediately encompassing prefix group, if needed
if len(succ) > 0 || prec != nil {
if hashOnly(curr[:maxLen]) {
e.branchHash(groups[maxLen])
} else {
e.branch(groups[maxLen])
}
}
groups = groups[:maxLen]
// Check the end of recursion
if precLen == 0 {
return groups
}
// Identify preceding key for the recursive invocation
newCurr := curr[:precLen]
var newPrec []byte
for len(groups) > 0 && groups[len(groups)-1] == 0 {
groups = groups[:len(groups)-1]
}
if len(groups) >= 1 {
newPrec = curr[:len(groups)-1]
}
// Recursion
return genStructStep(hashOnly, true, newPrec, newCurr, succ, e, groups)
}
// HashBuilder implements the interface `structInfoReceiver` and opcodes that the structural information of the trie
// is comprised of
// DESCRIBED: docs/programmers_guide/guide.md#separation-of-keys-and-the-structure
type HashBuilder struct {
hexKey bytes.Buffer // Next key-value pair to consume
hashStack []byte // Stack of sub-slices, each 33 bytes each, containing hashes (or RLP encodings, if shorter than 32 bytes)
nodeStack []node // Stack of nodes
value *bytebufferpool.ByteBuffer
sha keccakState // Keccak primitive that can absorb data (Write), and get squeezed to the hash out (Read)
leafFunc func(b []byte) (node, error) // Function to be called on the leafs to construct valueNode or accoutNode
}
// NewHashBuilder creates a new HashBuilder
func NewHashBuilder(leafFunc func(b []byte) (node, error)) *HashBuilder {
return &HashBuilder{
sha: sha3.NewLegacyKeccak256().(keccakState),
leafFunc: leafFunc,
}
}
// Reset makes the HashBuilder suitable for reuse
func (hb *HashBuilder) Reset() {
hb.hexKey.Reset()
hb.hashStack = hb.hashStack[:0]
hb.nodeStack = hb.nodeStack[:0]
pool.PutBuffer(hb.value)
hb.value = nil
}
// key is original key (not transformed into hex or compacted)
func (hb *HashBuilder) setKeyValue(skip int, key []byte, value *bytebufferpool.ByteBuffer) {
// Transform key into hex representation
hb.hexKey.Reset()
i := 0
for _, b := range key {
if i >= skip {
hb.hexKey.WriteByte(b / 16)
}
i++
if i >= skip {
hb.hexKey.WriteByte(b % 16)
}
i++
}
hb.hexKey.WriteByte(16)
pool.PutBuffer(hb.value)
hb.value = value
}
func (hb *HashBuilder) leaf(length int) {
//fmt.Printf("LEAF %d\n", length)
hex := hb.hexKey.Bytes()
key := hex[len(hex)-length:]
val, err := hb.leafFunc(hb.value.B)
if err != nil {
panic(err)
}
s := &shortNode{Key: common.CopyBytes(key), Val: val}
hb.nodeStack = append(hb.nodeStack, s)
hb.leafHash(length)
}
func (hb *HashBuilder) leafHash(length int) {
//fmt.Printf("LEAFHASH %d\n", length)
var hash [33]byte // RLP representation of hash (or un-hashes value)
// Compute the total length of binary representation
var keyPrefix [1]byte
var valPrefix [4]byte
var lenPrefix [4]byte
var kp, vp, kl, vl int
// Write key
var compactLen int
var ni int
var compact0 byte
hex := hb.hexKey.Bytes()
key := hex[len(hex)-length:]
if hasTerm(key) {
compactLen = (len(key)-1)/2 + 1
if len(key)&1 == 0 {
compact0 = 48 + key[0] // Odd (1<<4) + first nibble
ni = 1
} else {
compact0 = 32
}
} else {
compactLen = len(key)/2 + 1
if len(key)&1 == 1 {
compact0 = 16 + key[0] // Odd (1<<4) + first nibble
ni = 1
}
}
if compactLen > 1 {
keyPrefix[0] = byte(128 + compactLen)
kp = 1
kl = compactLen
} else {
kl = 1
}
val := hb.value.B
if len(val) > 1 || val[0] >= 128 {
vp = generateByteArrayLen(valPrefix[:], 0, len(val))
vl = len(val)
} else {
vl = 1
}
totalLen := kp + kl + vp + vl
pt := generateStructLen(lenPrefix[:], totalLen)
if pt+totalLen < 32 {
// Embedded node
pos := 0
copy(hash[pos:], lenPrefix[:pt])
pos += pt
copy(hash[pos:], keyPrefix[:kp])
pos += kp
hash[pos] = compact0
pos++
for i := 1; i < compactLen; i++ {
hash[pos] = key[ni]*16 + key[ni+1]
pos++
ni += 2
}
copy(hash[pos:], valPrefix[:vp])
pos += vp
copy(hash[pos:], val)
} else {
hb.sha.Reset()
if _, err := hb.sha.Write(lenPrefix[:pt]); err != nil {
panic(err)
}
if _, err := hb.sha.Write(keyPrefix[:kp]); err != nil {
panic(err)
}
var b [1]byte
b[0] = compact0
if _, err := hb.sha.Write(b[:]); err != nil {
panic(err)
}
for i := 1; i < compactLen; i++ {
b[0] = key[ni]*16 + key[ni+1]
if _, err := hb.sha.Write(b[:]); err != nil {
panic(err)
}
ni += 2
}
if _, err := hb.sha.Write(valPrefix[:vp]); err != nil {
panic(err)
}
if _, err := hb.sha.Write(val); err != nil {
panic(err)
}
hash[0] = byte(128 + 32)
if _, err := hb.sha.Read(hash[1:]); err != nil {
panic(err)
}
}
hb.hashStack = append(hb.hashStack, hash[:]...)
if len(hb.hashStack) > 33*len(hb.nodeStack) {
hb.nodeStack = append(hb.nodeStack, nil)
}
}
func (hb *HashBuilder) extension(key []byte) {
//fmt.Printf("EXTENSION %x\n", key)
nd := hb.nodeStack[len(hb.nodeStack)-1]
switch n := nd.(type) {
case nil:
branchHash := common.CopyBytes(hb.hashStack[len(hb.hashStack)-32:])
hb.nodeStack[len(hb.nodeStack)-1] = &shortNode{Key: common.CopyBytes(key), Val: hashNode(branchHash)}
case *fullNode:
hb.nodeStack[len(hb.nodeStack)-1] = &shortNode{Key: common.CopyBytes(key), Val: n}
default:
panic(fmt.Errorf("wrong Val type for an extension: %T", nd))
}
hb.extensionHash(key)
}
func (hb *HashBuilder) extensionHash(key []byte) {
//fmt.Printf("EXTENSIONHASH %x\n", key)
branchHash := hb.hashStack[len(hb.hashStack)-33:]
// Compute the total length of binary representation
var keyPrefix [1]byte
var lenPrefix [4]byte
var kp, kl int
// Write key
var compactLen int
var ni int
var compact0 byte
if hasTerm(key) {
compactLen = (len(key)-1)/2 + 1
if len(key)&1 == 0 {
compact0 = 48 + key[0] // Odd (1<<4) + first nibble
ni = 1
} else {
compact0 = 32
}
} else {
compactLen = len(key)/2 + 1
if len(key)&1 == 1 {
compact0 = 16 + key[0] // Odd (1<<4) + first nibble
ni = 1
}
}
if compactLen > 1 {
keyPrefix[0] = byte(128 + compactLen)
kp = 1
kl = compactLen
} else {
kl = 1
}
totalLen := kp + kl + 33
pt := generateStructLen(lenPrefix[:], totalLen)
hb.sha.Reset()
if _, err := hb.sha.Write(lenPrefix[:pt]); err != nil {
panic(err)
}
if _, err := hb.sha.Write(keyPrefix[:kp]); err != nil {
panic(err)
}
var b [1]byte
b[0] = compact0
if _, err := hb.sha.Write(b[:]); err != nil {
panic(err)
}
for i := 1; i < compactLen; i++ {
b[0] = key[ni]*16 + key[ni+1]
if _, err := hb.sha.Write(b[:]); err != nil {
panic(err)
}
ni += 2
}
if _, err := hb.sha.Write(branchHash); err != nil {
panic(err)
}
// Replace previous hash with the new one
if _, err := hb.sha.Read(hb.hashStack[len(hb.hashStack)-32:]); err != nil {
panic(err)
}
if _, ok := hb.nodeStack[len(hb.nodeStack)-1].(*fullNode); ok {
panic("extensionHash cannot be emitted when a node is on top of the stack")
}
}
func (hb *HashBuilder) branch(set uint32) {
//fmt.Printf("BRANCH %b\n", set)
f := &fullNode{}
digits := bits.OnesCount32(set)
nodes := hb.nodeStack[len(hb.nodeStack)-digits:]
hashes := hb.hashStack[len(hb.hashStack)-33*digits:]
var i int
for digit := uint(0); digit < 16; digit++ {
if ((uint32(1) << digit) & set) != 0 {
if nodes[i] == nil {
f.Children[digit] = hashNode(common.CopyBytes(hashes[33*i+1 : 33*i+33]))
} else {
f.Children[digit] = nodes[i]
}
i++
}
}
hb.nodeStack = hb.nodeStack[:len(hb.nodeStack)-digits+1]
hb.nodeStack[len(hb.nodeStack)-1] = f
hb.branchHash(set)
copy(f.flags.hash[:], hb.hashStack[len(hb.hashStack)-32:])
}
func (hb *HashBuilder) branchHash(set uint32) {
//fmt.Printf("BRANCHHASH %b\n", set)
digits := bits.OnesCount32(set)
hashes := hb.hashStack[len(hb.hashStack)-33*digits:]
// Calculate the size of the resulting RLP
totalSize := 17 // These are 17 length prefixes
var i int
for digit := uint(0); digit < 16; digit++ {
if ((uint32(1) << digit) & set) != 0 {
if hashes[33*i] == byte(128+32) {
totalSize += 32
} else {
// Embedded node
totalSize += int(hashes[33*i]) - 192
}
i++
}
}
hb.sha.Reset()
var lenPrefix [4]byte
pt := generateStructLen(lenPrefix[:], totalSize)
if _, err := hb.sha.Write(lenPrefix[:pt]); err != nil {
panic(err)
}
// Output children hashes or embedded RLPs
i = 0
var b [1]byte
b[0] = 128
for digit := uint(0); digit < 17; digit++ {
if ((uint32(1) << digit) & set) != 0 {
if hashes[33*i] == byte(128+32) {
if _, err := hb.sha.Write(hashes[33*i : 33*i+33]); err != nil {
panic(err)
}
} else {
// Embedded node
size := int(hashes[33*i]) - 192
if _, err := hb.sha.Write(hashes[33*i : 33*i+size+1]); err != nil {
panic(err)
}
}
i++
} else {
if _, err := hb.sha.Write(b[:]); err != nil {
panic(err)
}
}
}
hb.hashStack = hb.hashStack[:len(hb.hashStack)-33*digits+33]
hb.hashStack[len(hb.hashStack)-33] = 128 + 32
if _, err := hb.sha.Read(hb.hashStack[len(hb.hashStack)-32:]); err != nil {
panic(err)
}
if 33*len(hb.nodeStack) > len(hb.hashStack) {
hb.nodeStack = hb.nodeStack[:len(hb.nodeStack)-digits+1]
hb.nodeStack[len(hb.nodeStack)-1] = nil
}
}
func (hb *HashBuilder) hash(number int) {
panic("not implemented")
}
func (hb *HashBuilder) rootHash() common.Hash {
var hash common.Hash
copy(hash[:], hb.hashStack[1:33])
return hash
}
func (hb *HashBuilder) root() node {
return hb.nodeStack[0]
}
func (hb *HashBuilder) hasRoot() bool {
return len(hb.nodeStack) > 0
}