// 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 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 snapshot
import (
"fmt"
"math/big"
"math/rand"
"testing"
"github.com/VictoriaMetrics/fastcache"
"github.com/ava-labs/coreth/core/rawdb"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/rlp"
)
// randomHash generates a random blob of data and returns it as a hash.
func randomHash() common.Hash {
var hash common.Hash
if n, err := rand.Read(hash[:]); n != common.HashLength || err != nil {
panic(err)
}
return hash
}
// randomAccount generates a random account and returns it RLP encoded.
func randomAccount() []byte {
root := randomHash()
a := Account{
Balance: big.NewInt(rand.Int63()),
Nonce: rand.Uint64(),
Root: root[:],
CodeHash: emptyCode[:],
}
data, _ := rlp.EncodeToBytes(a)
return data
}
// randomAccountSet generates a set of random accounts with the given strings as
// the account address hashes.
func randomAccountSet(hashes ...string) map[common.Hash][]byte {
accounts := make(map[common.Hash][]byte)
for _, hash := range hashes {
accounts[common.HexToHash(hash)] = randomAccount()
}
return accounts
}
// randomStorageSet generates a set of random slots with the given strings as
// the slot addresses.
func randomStorageSet(accounts []string, hashes [][]string, nilStorage [][]string) map[common.Hash]map[common.Hash][]byte {
storages := make(map[common.Hash]map[common.Hash][]byte)
for index, account := range accounts {
storages[common.HexToHash(account)] = make(map[common.Hash][]byte)
if index < len(hashes) {
hashes := hashes[index]
for _, hash := range hashes {
storages[common.HexToHash(account)][common.HexToHash(hash)] = randomHash().Bytes()
}
}
if index < len(nilStorage) {
nils := nilStorage[index]
for _, hash := range nils {
storages[common.HexToHash(account)][common.HexToHash(hash)] = nil
}
}
}
return storages
}
// Tests that if a disk layer becomes stale, no active external references will
// be returned with junk data. This version of the test flattens every diff layer
// to check internal corner case around the bottom-most memory accumulator.
func TestDiskLayerExternalInvalidationFullFlatten(t *testing.T) {
// Create an empty base layer and a snapshot tree out of it
base := &diskLayer{
diskdb: rawdb.NewMemoryDatabase(),
root: common.HexToHash("0x01"),
cache: fastcache.New(1024 * 500),
}
snaps := &Tree{
layers: map[common.Hash]snapshot{
base.root: base,
},
}
// Retrieve a reference to the base and commit a diff on top
ref := snaps.Snapshot(base.root)
accounts := map[common.Hash][]byte{
common.HexToHash("0xa1"): randomAccount(),
}
if err := snaps.Update(common.HexToHash("0x02"), common.HexToHash("0x01"), nil, accounts, nil); err != nil {
t.Fatalf("failed to create a diff layer: %v", err)
}
if n := len(snaps.layers); n != 2 {
t.Errorf("pre-cap layer count mismatch: have %d, want %d", n, 2)
}
// Commit the diff layer onto the disk and ensure it's persisted
if err := snaps.Cap(common.HexToHash("0x02"), 0); err != nil {
t.Fatalf("failed to merge diff layer onto disk: %v", err)
}
// Since the base layer was modified, ensure that data retrieval on the external reference fail
if acc, err := ref.Account(common.HexToHash("0x01")); err != ErrSnapshotStale {
t.Errorf("stale reference returned account: %#x (err: %v)", acc, err)
}
if slot, err := ref.Storage(common.HexToHash("0xa1"), common.HexToHash("0xb1")); err != ErrSnapshotStale {
t.Errorf("stale reference returned storage slot: %#x (err: %v)", slot, err)
}
if n := len(snaps.layers); n != 1 {
t.Errorf("post-cap layer count mismatch: have %d, want %d", n, 1)
fmt.Println(snaps.layers)
}
}
// Tests that if a disk layer becomes stale, no active external references will
// be returned with junk data. This version of the test retains the bottom diff
// layer to check the usual mode of operation where the accumulator is retained.
func TestDiskLayerExternalInvalidationPartialFlatten(t *testing.T) {
// Create an empty base layer and a snapshot tree out of it
base := &diskLayer{
diskdb: rawdb.NewMemoryDatabase(),
root: common.HexToHash("0x01"),
cache: fastcache.New(1024 * 500),
}
snaps := &Tree{
layers: map[common.Hash]snapshot{
base.root: base,
},
}
// Retrieve a reference to the base and commit two diffs on top
ref := snaps.Snapshot(base.root)
accounts := map[common.Hash][]byte{
common.HexToHash("0xa1"): randomAccount(),
}
if err := snaps.Update(common.HexToHash("0x02"), common.HexToHash("0x01"), nil, accounts, nil); err != nil {
t.Fatalf("failed to create a diff layer: %v", err)
}
if err := snaps.Update(common.HexToHash("0x03"), common.HexToHash("0x02"), nil, accounts, nil); err != nil {
t.Fatalf("failed to create a diff layer: %v", err)
}
if n := len(snaps.layers); n != 3 {
t.Errorf("pre-cap layer count mismatch: have %d, want %d", n, 3)
}
// Commit the diff layer onto the disk and ensure it's persisted
defer func(memcap uint64) { aggregatorMemoryLimit = memcap }(aggregatorMemoryLimit)
aggregatorMemoryLimit = 0
if err := snaps.Cap(common.HexToHash("0x03"), 2); err != nil {
t.Fatalf("failed to merge diff layer onto disk: %v", err)
}
// Since the base layer was modified, ensure that data retrievald on the external reference fail
if acc, err := ref.Account(common.HexToHash("0x01")); err != ErrSnapshotStale {
t.Errorf("stale reference returned account: %#x (err: %v)", acc, err)
}
if slot, err := ref.Storage(common.HexToHash("0xa1"), common.HexToHash("0xb1")); err != ErrSnapshotStale {
t.Errorf("stale reference returned storage slot: %#x (err: %v)", slot, err)
}
if n := len(snaps.layers); n != 2 {
t.Errorf("post-cap layer count mismatch: have %d, want %d", n, 2)
fmt.Println(snaps.layers)
}
}
// Tests that if a diff layer becomes stale, no active external references will
// be returned with junk data. This version of the test flattens every diff layer
// to check internal corner case around the bottom-most memory accumulator.
func TestDiffLayerExternalInvalidationFullFlatten(t *testing.T) {
// Create an empty base layer and a snapshot tree out of it
base := &diskLayer{
diskdb: rawdb.NewMemoryDatabase(),
root: common.HexToHash("0x01"),
cache: fastcache.New(1024 * 500),
}
snaps := &Tree{
layers: map[common.Hash]snapshot{
base.root: base,
},
}
// Commit two diffs on top and retrieve a reference to the bottommost
accounts := map[common.Hash][]byte{
common.HexToHash("0xa1"): randomAccount(),
}
if err := snaps.Update(common.HexToHash("0x02"), common.HexToHash("0x01"), nil, accounts, nil); err != nil {
t.Fatalf("failed to create a diff layer: %v", err)
}
if err := snaps.Update(common.HexToHash("0x03"), common.HexToHash("0x02"), nil, accounts, nil); err != nil {
t.Fatalf("failed to create a diff layer: %v", err)
}
if n := len(snaps.layers); n != 3 {
t.Errorf("pre-cap layer count mismatch: have %d, want %d", n, 3)
}
ref := snaps.Snapshot(common.HexToHash("0x02"))
// Flatten the diff layer into the bottom accumulator
if err := snaps.Cap(common.HexToHash("0x03"), 1); err != nil {
t.Fatalf("failed to flatten diff layer into accumulator: %v", err)
}
// Since the accumulator diff layer was modified, ensure that data retrievald on the external reference fail
if acc, err := ref.Account(common.HexToHash("0x01")); err != ErrSnapshotStale {
t.Errorf("stale reference returned account: %#x (err: %v)", acc, err)
}
if slot, err := ref.Storage(common.HexToHash("0xa1"), common.HexToHash("0xb1")); err != ErrSnapshotStale {
t.Errorf("stale reference returned storage slot: %#x (err: %v)", slot, err)
}
if n := len(snaps.layers); n != 2 {
t.Errorf("post-cap layer count mismatch: have %d, want %d", n, 2)
fmt.Println(snaps.layers)
}
}
// Tests that if a diff layer becomes stale, no active external references will
// be returned with junk data. This version of the test retains the bottom diff
// layer to check the usual mode of operation where the accumulator is retained.
func TestDiffLayerExternalInvalidationPartialFlatten(t *testing.T) {
// Create an empty base layer and a snapshot tree out of it
base := &diskLayer{
diskdb: rawdb.NewMemoryDatabase(),
root: common.HexToHash("0x01"),
cache: fastcache.New(1024 * 500),
}
snaps := &Tree{
layers: map[common.Hash]snapshot{
base.root: base,
},
}
// Commit three diffs on top and retrieve a reference to the bottommost
accounts := map[common.Hash][]byte{
common.HexToHash("0xa1"): randomAccount(),
}
if err := snaps.Update(common.HexToHash("0x02"), common.HexToHash("0x01"), nil, accounts, nil); err != nil {
t.Fatalf("failed to create a diff layer: %v", err)
}
if err := snaps.Update(common.HexToHash("0x03"), common.HexToHash("0x02"), nil, accounts, nil); err != nil {
t.Fatalf("failed to create a diff layer: %v", err)
}
if err := snaps.Update(common.HexToHash("0x04"), common.HexToHash("0x03"), nil, accounts, nil); err != nil {
t.Fatalf("failed to create a diff layer: %v", err)
}
if n := len(snaps.layers); n != 4 {
t.Errorf("pre-cap layer count mismatch: have %d, want %d", n, 4)
}
ref := snaps.Snapshot(common.HexToHash("0x02"))
// Doing a Cap operation with many allowed layers should be a no-op
exp := len(snaps.layers)
if err := snaps.Cap(common.HexToHash("0x04"), 2000); err != nil {
t.Fatalf("failed to flatten diff layer into accumulator: %v", err)
}
if got := len(snaps.layers); got != exp {
t.Errorf("layers modified, got %d exp %d", got, exp)
}
// Flatten the diff layer into the bottom accumulator
if err := snaps.Cap(common.HexToHash("0x04"), 2); err != nil {
t.Fatalf("failed to flatten diff layer into accumulator: %v", err)
}
// Since the accumulator diff layer was modified, ensure that data retrievald on the external reference fail
if acc, err := ref.Account(common.HexToHash("0x01")); err != ErrSnapshotStale {
t.Errorf("stale reference returned account: %#x (err: %v)", acc, err)
}
if slot, err := ref.Storage(common.HexToHash("0xa1"), common.HexToHash("0xb1")); err != ErrSnapshotStale {
t.Errorf("stale reference returned storage slot: %#x (err: %v)", slot, err)
}
if n := len(snaps.layers); n != 3 {
t.Errorf("post-cap layer count mismatch: have %d, want %d", n, 3)
fmt.Println(snaps.layers)
}
}
// TestPostCapBasicDataAccess tests some functionality regarding capping/flattening.
func TestPostCapBasicDataAccess(t *testing.T) {
// setAccount is a helper to construct a random account entry and assign it to
// an account slot in a snapshot
setAccount := func(accKey string) map[common.Hash][]byte {
return map[common.Hash][]byte{
common.HexToHash(accKey): randomAccount(),
}
}
// Create a starting base layer and a snapshot tree out of it
base := &diskLayer{
diskdb: rawdb.NewMemoryDatabase(),
root: common.HexToHash("0x01"),
cache: fastcache.New(1024 * 500),
}
snaps := &Tree{
layers: map[common.Hash]snapshot{
base.root: base,
},
}
// The lowest difflayer
snaps.Update(common.HexToHash("0xa1"), common.HexToHash("0x01"), nil, setAccount("0xa1"), nil)
snaps.Update(common.HexToHash("0xa2"), common.HexToHash("0xa1"), nil, setAccount("0xa2"), nil)
snaps.Update(common.HexToHash("0xb2"), common.HexToHash("0xa1"), nil, setAccount("0xb2"), nil)
snaps.Update(common.HexToHash("0xa3"), common.HexToHash("0xa2"), nil, setAccount("0xa3"), nil)
snaps.Update(common.HexToHash("0xb3"), common.HexToHash("0xb2"), nil, setAccount("0xb3"), nil)
// checkExist verifies if an account exiss in a snapshot
checkExist := func(layer *diffLayer, key string) error {
if data, _ := layer.Account(common.HexToHash(key)); data == nil {
return fmt.Errorf("expected %x to exist, got nil", common.HexToHash(key))
}
return nil
}
// shouldErr checks that an account access errors as expected
shouldErr := func(layer *diffLayer, key string) error {
if data, err := layer.Account(common.HexToHash(key)); err == nil {
return fmt.Errorf("expected error, got data %x", data)
}
return nil
}
// check basics
snap := snaps.Snapshot(common.HexToHash("0xb3")).(*diffLayer)
if err := checkExist(snap, "0xa1"); err != nil {
t.Error(err)
}
if err := checkExist(snap, "0xb2"); err != nil {
t.Error(err)
}
if err := checkExist(snap, "0xb3"); err != nil {
t.Error(err)
}
// Cap to a bad root should fail
if err := snaps.Cap(common.HexToHash("0x1337"), 0); err == nil {
t.Errorf("expected error, got none")
}
// Now, merge the a-chain
snaps.Cap(common.HexToHash("0xa3"), 0)
// At this point, a2 got merged into a1. Thus, a1 is now modified, and as a1 is
// the parent of b2, b2 should no longer be able to iterate into parent.
// These should still be accessible
if err := checkExist(snap, "0xb2"); err != nil {
t.Error(err)
}
if err := checkExist(snap, "0xb3"); err != nil {
t.Error(err)
}
// But these would need iteration into the modified parent
if err := shouldErr(snap, "0xa1"); err != nil {
t.Error(err)
}
if err := shouldErr(snap, "0xa2"); err != nil {
t.Error(err)
}
if err := shouldErr(snap, "0xa3"); err != nil {
t.Error(err)
}
// Now, merge it again, just for fun. It should now error, since a3
// is a disk layer
if err := snaps.Cap(common.HexToHash("0xa3"), 0); err == nil {
t.Error("expected error capping the disk layer, got none")
}
}