feat: Waku v2 bridge

Issue #12610

vendor/github.com/ethereum/go-ethereum/eth/filters/api.go

@@ -0,0 +1,573 @@
+// Copyright 2015 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 filters
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"math/big"
+	"sync"
+	"time"
+
+	"github.com/ethereum/go-ethereum"
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/common/hexutil"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/rpc"
+)
+
+// filter is a helper struct that holds meta information over the filter type
+// and associated subscription in the event system.
+type filter struct {
+	typ      Type
+	deadline *time.Timer // filter is inactive when deadline triggers
+	hashes   []common.Hash
+	txs      []*types.Transaction
+	crit     FilterCriteria
+	logs     []*types.Log
+	s        *Subscription // associated subscription in event system
+}
+
+// FilterAPI offers support to create and manage filters. This will allow external clients to retrieve various
+// information related to the Ethereum protocol such als blocks, transactions and logs.
+type FilterAPI struct {
+	sys       *FilterSystem
+	events    *EventSystem
+	filtersMu sync.Mutex
+	filters   map[rpc.ID]*filter
+	timeout   time.Duration
+}
+
+// NewFilterAPI returns a new FilterAPI instance.
+func NewFilterAPI(system *FilterSystem, lightMode bool) *FilterAPI {
+	api := &FilterAPI{
+		sys:     system,
+		events:  NewEventSystem(system, lightMode),
+		filters: make(map[rpc.ID]*filter),
+		timeout: system.cfg.Timeout,
+	}
+	go api.timeoutLoop(system.cfg.Timeout)
+
+	return api
+}
+
+// timeoutLoop runs at the interval set by 'timeout' and deletes filters
+// that have not been recently used. It is started when the API is created.
+func (api *FilterAPI) timeoutLoop(timeout time.Duration) {
+	var toUninstall []*Subscription
+	ticker := time.NewTicker(timeout)
+	defer ticker.Stop()
+	for {
+		<-ticker.C
+		api.filtersMu.Lock()
+		for id, f := range api.filters {
+			select {
+			case <-f.deadline.C:
+				toUninstall = append(toUninstall, f.s)
+				delete(api.filters, id)
+			default:
+				continue
+			}
+		}
+		api.filtersMu.Unlock()
+
+		// Unsubscribes are processed outside the lock to avoid the following scenario:
+		// event loop attempts broadcasting events to still active filters while
+		// Unsubscribe is waiting for it to process the uninstall request.
+		for _, s := range toUninstall {
+			s.Unsubscribe()
+		}
+		toUninstall = nil
+	}
+}
+
+// NewPendingTransactionFilter creates a filter that fetches pending transactions
+// as transactions enter the pending state.
+//
+// It is part of the filter package because this filter can be used through the
+// `eth_getFilterChanges` polling method that is also used for log filters.
+func (api *FilterAPI) NewPendingTransactionFilter() rpc.ID {
+	var (
+		pendingTxs   = make(chan []*types.Transaction)
+		pendingTxSub = api.events.SubscribePendingTxs(pendingTxs)
+	)
+
+	api.filtersMu.Lock()
+	api.filters[pendingTxSub.ID] = &filter{typ: PendingTransactionsSubscription, deadline: time.NewTimer(api.timeout), txs: make([]*types.Transaction, 0), s: pendingTxSub}
+	api.filtersMu.Unlock()
+
+	go func() {
+		for {
+			select {
+			case pTx := <-pendingTxs:
+				api.filtersMu.Lock()
+				if f, found := api.filters[pendingTxSub.ID]; found {
+					f.txs = append(f.txs, pTx...)
+				}
+				api.filtersMu.Unlock()
+			case <-pendingTxSub.Err():
+				api.filtersMu.Lock()
+				delete(api.filters, pendingTxSub.ID)
+				api.filtersMu.Unlock()
+				return
+			}
+		}
+	}()
+
+	return pendingTxSub.ID
+}
+
+// NewPendingTransactions creates a subscription that is triggered each time a
+// transaction enters the transaction pool. If fullTx is true the full tx is
+// sent to the client, otherwise the hash is sent.
+func (api *FilterAPI) NewPendingTransactions(ctx context.Context, fullTx *bool) (*rpc.Subscription, error) {
+	notifier, supported := rpc.NotifierFromContext(ctx)
+	if !supported {
+		return &rpc.Subscription{}, rpc.ErrNotificationsUnsupported
+	}
+
+	rpcSub := notifier.CreateSubscription()
+
+	go func() {
+		txs := make(chan []*types.Transaction, 128)
+		pendingTxSub := api.events.SubscribePendingTxs(txs)
+
+		for {
+			select {
+			case txs := <-txs:
+				// To keep the original behaviour, send a single tx hash in one notification.
+				// TODO(rjl493456442) Send a batch of tx hashes in one notification
+				for _, tx := range txs {
+					if fullTx != nil && *fullTx {
+						notifier.Notify(rpcSub.ID, tx)
+					} else {
+						notifier.Notify(rpcSub.ID, tx.Hash())
+					}
+				}
+			case <-rpcSub.Err():
+				pendingTxSub.Unsubscribe()
+				return
+			case <-notifier.Closed():
+				pendingTxSub.Unsubscribe()
+				return
+			}
+		}
+	}()
+
+	return rpcSub, nil
+}
+
+// NewBlockFilter creates a filter that fetches blocks that are imported into the chain.
+// It is part of the filter package since polling goes with eth_getFilterChanges.
+func (api *FilterAPI) NewBlockFilter() rpc.ID {
+	var (
+		headers   = make(chan *types.Header)
+		headerSub = api.events.SubscribeNewHeads(headers)
+	)
+
+	api.filtersMu.Lock()
+	api.filters[headerSub.ID] = &filter{typ: BlocksSubscription, deadline: time.NewTimer(api.timeout), hashes: make([]common.Hash, 0), s: headerSub}
+	api.filtersMu.Unlock()
+
+	go func() {
+		for {
+			select {
+			case h := <-headers:
+				api.filtersMu.Lock()
+				if f, found := api.filters[headerSub.ID]; found {
+					f.hashes = append(f.hashes, h.Hash())
+				}
+				api.filtersMu.Unlock()
+			case <-headerSub.Err():
+				api.filtersMu.Lock()
+				delete(api.filters, headerSub.ID)
+				api.filtersMu.Unlock()
+				return
+			}
+		}
+	}()
+
+	return headerSub.ID
+}
+
+// NewHeads send a notification each time a new (header) block is appended to the chain.
+func (api *FilterAPI) NewHeads(ctx context.Context) (*rpc.Subscription, error) {
+	notifier, supported := rpc.NotifierFromContext(ctx)
+	if !supported {
+		return &rpc.Subscription{}, rpc.ErrNotificationsUnsupported
+	}
+
+	rpcSub := notifier.CreateSubscription()
+
+	go func() {
+		headers := make(chan *types.Header)
+		headersSub := api.events.SubscribeNewHeads(headers)
+
+		for {
+			select {
+			case h := <-headers:
+				notifier.Notify(rpcSub.ID, h)
+			case <-rpcSub.Err():
+				headersSub.Unsubscribe()
+				return
+			case <-notifier.Closed():
+				headersSub.Unsubscribe()
+				return
+			}
+		}
+	}()
+
+	return rpcSub, nil
+}
+
+// Logs creates a subscription that fires for all new log that match the given filter criteria.
+func (api *FilterAPI) Logs(ctx context.Context, crit FilterCriteria) (*rpc.Subscription, error) {
+	notifier, supported := rpc.NotifierFromContext(ctx)
+	if !supported {
+		return &rpc.Subscription{}, rpc.ErrNotificationsUnsupported
+	}
+
+	var (
+		rpcSub      = notifier.CreateSubscription()
+		matchedLogs = make(chan []*types.Log)
+	)
+
+	logsSub, err := api.events.SubscribeLogs(ethereum.FilterQuery(crit), matchedLogs)
+	if err != nil {
+		return nil, err
+	}
+
+	go func() {
+		for {
+			select {
+			case logs := <-matchedLogs:
+				for _, log := range logs {
+					log := log
+					notifier.Notify(rpcSub.ID, &log)
+				}
+			case <-rpcSub.Err(): // client send an unsubscribe request
+				logsSub.Unsubscribe()
+				return
+			case <-notifier.Closed(): // connection dropped
+				logsSub.Unsubscribe()
+				return
+			}
+		}
+	}()
+
+	return rpcSub, nil
+}
+
+// FilterCriteria represents a request to create a new filter.
+// Same as ethereum.FilterQuery but with UnmarshalJSON() method.
+type FilterCriteria ethereum.FilterQuery
+
+// NewFilter creates a new filter and returns the filter id. It can be
+// used to retrieve logs when the state changes. This method cannot be
+// used to fetch logs that are already stored in the state.
+//
+// Default criteria for the from and to block are "latest".
+// Using "latest" as block number will return logs for mined blocks.
+// Using "pending" as block number returns logs for not yet mined (pending) blocks.
+// In case logs are removed (chain reorg) previously returned logs are returned
+// again but with the removed property set to true.
+//
+// In case "fromBlock" > "toBlock" an error is returned.
+func (api *FilterAPI) NewFilter(crit FilterCriteria) (rpc.ID, error) {
+	logs := make(chan []*types.Log)
+	logsSub, err := api.events.SubscribeLogs(ethereum.FilterQuery(crit), logs)
+	if err != nil {
+		return "", err
+	}
+
+	api.filtersMu.Lock()
+	api.filters[logsSub.ID] = &filter{typ: LogsSubscription, crit: crit, deadline: time.NewTimer(api.timeout), logs: make([]*types.Log, 0), s: logsSub}
+	api.filtersMu.Unlock()
+
+	go func() {
+		for {
+			select {
+			case l := <-logs:
+				api.filtersMu.Lock()
+				if f, found := api.filters[logsSub.ID]; found {
+					f.logs = append(f.logs, l...)
+				}
+				api.filtersMu.Unlock()
+			case <-logsSub.Err():
+				api.filtersMu.Lock()
+				delete(api.filters, logsSub.ID)
+				api.filtersMu.Unlock()
+				return
+			}
+		}
+	}()
+
+	return logsSub.ID, nil
+}
+
+// GetLogs returns logs matching the given argument that are stored within the state.
+func (api *FilterAPI) GetLogs(ctx context.Context, crit FilterCriteria) ([]*types.Log, error) {
+	var filter *Filter
+	if crit.BlockHash != nil {
+		// Block filter requested, construct a single-shot filter
+		filter = api.sys.NewBlockFilter(*crit.BlockHash, crit.Addresses, crit.Topics)
+	} else {
+		// Convert the RPC block numbers into internal representations
+		begin := rpc.LatestBlockNumber.Int64()
+		if crit.FromBlock != nil {
+			begin = crit.FromBlock.Int64()
+		}
+		end := rpc.LatestBlockNumber.Int64()
+		if crit.ToBlock != nil {
+			end = crit.ToBlock.Int64()
+		}
+		// Construct the range filter
+		filter = api.sys.NewRangeFilter(begin, end, crit.Addresses, crit.Topics)
+	}
+	// Run the filter and return all the logs
+	logs, err := filter.Logs(ctx)
+	if err != nil {
+		return nil, err
+	}
+	return returnLogs(logs), err
+}
+
+// UninstallFilter removes the filter with the given filter id.
+func (api *FilterAPI) UninstallFilter(id rpc.ID) bool {
+	api.filtersMu.Lock()
+	f, found := api.filters[id]
+	if found {
+		delete(api.filters, id)
+	}
+	api.filtersMu.Unlock()
+	if found {
+		f.s.Unsubscribe()
+	}
+
+	return found
+}
+
+// GetFilterLogs returns the logs for the filter with the given id.
+// If the filter could not be found an empty array of logs is returned.
+func (api *FilterAPI) GetFilterLogs(ctx context.Context, id rpc.ID) ([]*types.Log, error) {
+	api.filtersMu.Lock()
+	f, found := api.filters[id]
+	api.filtersMu.Unlock()
+
+	if !found || f.typ != LogsSubscription {
+		return nil, fmt.Errorf("filter not found")
+	}
+
+	var filter *Filter
+	if f.crit.BlockHash != nil {
+		// Block filter requested, construct a single-shot filter
+		filter = api.sys.NewBlockFilter(*f.crit.BlockHash, f.crit.Addresses, f.crit.Topics)
+	} else {
+		// Convert the RPC block numbers into internal representations
+		begin := rpc.LatestBlockNumber.Int64()
+		if f.crit.FromBlock != nil {
+			begin = f.crit.FromBlock.Int64()
+		}
+		end := rpc.LatestBlockNumber.Int64()
+		if f.crit.ToBlock != nil {
+			end = f.crit.ToBlock.Int64()
+		}
+		// Construct the range filter
+		filter = api.sys.NewRangeFilter(begin, end, f.crit.Addresses, f.crit.Topics)
+	}
+	// Run the filter and return all the logs
+	logs, err := filter.Logs(ctx)
+	if err != nil {
+		return nil, err
+	}
+	return returnLogs(logs), nil
+}
+
+// GetFilterChanges returns the logs for the filter with the given id since
+// last time it was called. This can be used for polling.
+//
+// For pending transaction and block filters the result is []common.Hash.
+// (pending)Log filters return []Log.
+func (api *FilterAPI) GetFilterChanges(id rpc.ID) (interface{}, error) {
+	api.filtersMu.Lock()
+	defer api.filtersMu.Unlock()
+
+	if f, found := api.filters[id]; found {
+		if !f.deadline.Stop() {
+			// timer expired but filter is not yet removed in timeout loop
+			// receive timer value and reset timer
+			<-f.deadline.C
+		}
+		f.deadline.Reset(api.timeout)
+
+		switch f.typ {
+		case BlocksSubscription:
+			hashes := f.hashes
+			f.hashes = nil
+			return returnHashes(hashes), nil
+		case PendingTransactionsSubscription:
+			txs := f.txs
+			f.txs = nil
+			return txs, nil
+		case LogsSubscription, MinedAndPendingLogsSubscription:
+			logs := f.logs
+			f.logs = nil
+			return returnLogs(logs), nil
+		}
+	}
+
+	return []interface{}{}, fmt.Errorf("filter not found")
+}
+
+// returnHashes is a helper that will return an empty hash array case the given hash array is nil,
+// otherwise the given hashes array is returned.
+func returnHashes(hashes []common.Hash) []common.Hash {
+	if hashes == nil {
+		return []common.Hash{}
+	}
+	return hashes
+}
+
+// returnLogs is a helper that will return an empty log array in case the given logs array is nil,
+// otherwise the given logs array is returned.
+func returnLogs(logs []*types.Log) []*types.Log {
+	if logs == nil {
+		return []*types.Log{}
+	}
+	return logs
+}
+
+// UnmarshalJSON sets *args fields with given data.
+func (args *FilterCriteria) UnmarshalJSON(data []byte) error {
+	type input struct {
+		BlockHash *common.Hash     `json:"blockHash"`
+		FromBlock *rpc.BlockNumber `json:"fromBlock"`
+		ToBlock   *rpc.BlockNumber `json:"toBlock"`
+		Addresses interface{}      `json:"address"`
+		Topics    []interface{}    `json:"topics"`
+	}
+
+	var raw input
+	if err := json.Unmarshal(data, &raw); err != nil {
+		return err
+	}
+
+	if raw.BlockHash != nil {
+		if raw.FromBlock != nil || raw.ToBlock != nil {
+			// BlockHash is mutually exclusive with FromBlock/ToBlock criteria
+			return fmt.Errorf("cannot specify both BlockHash and FromBlock/ToBlock, choose one or the other")
+		}
+		args.BlockHash = raw.BlockHash
+	} else {
+		if raw.FromBlock != nil {
+			args.FromBlock = big.NewInt(raw.FromBlock.Int64())
+		}
+
+		if raw.ToBlock != nil {
+			args.ToBlock = big.NewInt(raw.ToBlock.Int64())
+		}
+	}
+
+	args.Addresses = []common.Address{}
+
+	if raw.Addresses != nil {
+		// raw.Address can contain a single address or an array of addresses
+		switch rawAddr := raw.Addresses.(type) {
+		case []interface{}:
+			for i, addr := range rawAddr {
+				if strAddr, ok := addr.(string); ok {
+					addr, err := decodeAddress(strAddr)
+					if err != nil {
+						return fmt.Errorf("invalid address at index %d: %v", i, err)
+					}
+					args.Addresses = append(args.Addresses, addr)
+				} else {
+					return fmt.Errorf("non-string address at index %d", i)
+				}
+			}
+		case string:
+			addr, err := decodeAddress(rawAddr)
+			if err != nil {
+				return fmt.Errorf("invalid address: %v", err)
+			}
+			args.Addresses = []common.Address{addr}
+		default:
+			return errors.New("invalid addresses in query")
+		}
+	}
+
+	// topics is an array consisting of strings and/or arrays of strings.
+	// JSON null values are converted to common.Hash{} and ignored by the filter manager.
+	if len(raw.Topics) > 0 {
+		args.Topics = make([][]common.Hash, len(raw.Topics))
+		for i, t := range raw.Topics {
+			switch topic := t.(type) {
+			case nil:
+				// ignore topic when matching logs
+
+			case string:
+				// match specific topic
+				top, err := decodeTopic(topic)
+				if err != nil {
+					return err
+				}
+				args.Topics[i] = []common.Hash{top}
+
+			case []interface{}:
+				// or case e.g. [null, "topic0", "topic1"]
+				for _, rawTopic := range topic {
+					if rawTopic == nil {
+						// null component, match all
+						args.Topics[i] = nil
+						break
+					}
+					if topic, ok := rawTopic.(string); ok {
+						parsed, err := decodeTopic(topic)
+						if err != nil {
+							return err
+						}
+						args.Topics[i] = append(args.Topics[i], parsed)
+					} else {
+						return fmt.Errorf("invalid topic(s)")
+					}
+				}
+			default:
+				return fmt.Errorf("invalid topic(s)")
+			}
+		}
+	}
+
+	return nil
+}
+
+func decodeAddress(s string) (common.Address, error) {
+	b, err := hexutil.Decode(s)
+	if err == nil && len(b) != common.AddressLength {
+		err = fmt.Errorf("hex has invalid length %d after decoding; expected %d for address", len(b), common.AddressLength)
+	}
+	return common.BytesToAddress(b), err
+}
+
+func decodeTopic(s string) (common.Hash, error) {
+	b, err := hexutil.Decode(s)
+	if err == nil && len(b) != common.HashLength {
+		err = fmt.Errorf("hex has invalid length %d after decoding; expected %d for topic", len(b), common.HashLength)
+	}
+	return common.BytesToHash(b), err
+}

vendor/github.com/ethereum/go-ethereum/eth/filters/filter.go

@@ -0,0 +1,387 @@
+// Copyright 2014 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 filters
+
+import (
+	"context"
+	"errors"
+	"math/big"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core/bloombits"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/rpc"
+)
+
+// Filter can be used to retrieve and filter logs.
+type Filter struct {
+	sys *FilterSystem
+
+	addresses []common.Address
+	topics    [][]common.Hash
+
+	block      common.Hash // Block hash if filtering a single block
+	begin, end int64       // Range interval if filtering multiple blocks
+
+	matcher *bloombits.Matcher
+}
+
+// NewRangeFilter creates a new filter which uses a bloom filter on blocks to
+// figure out whether a particular block is interesting or not.
+func (sys *FilterSystem) NewRangeFilter(begin, end int64, addresses []common.Address, topics [][]common.Hash) *Filter {
+	// Flatten the address and topic filter clauses into a single bloombits filter
+	// system. Since the bloombits are not positional, nil topics are permitted,
+	// which get flattened into a nil byte slice.
+	var filters [][][]byte
+	if len(addresses) > 0 {
+		filter := make([][]byte, len(addresses))
+		for i, address := range addresses {
+			filter[i] = address.Bytes()
+		}
+		filters = append(filters, filter)
+	}
+	for _, topicList := range topics {
+		filter := make([][]byte, len(topicList))
+		for i, topic := range topicList {
+			filter[i] = topic.Bytes()
+		}
+		filters = append(filters, filter)
+	}
+	size, _ := sys.backend.BloomStatus()
+
+	// Create a generic filter and convert it into a range filter
+	filter := newFilter(sys, addresses, topics)
+
+	filter.matcher = bloombits.NewMatcher(size, filters)
+	filter.begin = begin
+	filter.end = end
+
+	return filter
+}
+
+// NewBlockFilter creates a new filter which directly inspects the contents of
+// a block to figure out whether it is interesting or not.
+func (sys *FilterSystem) NewBlockFilter(block common.Hash, addresses []common.Address, topics [][]common.Hash) *Filter {
+	// Create a generic filter and convert it into a block filter
+	filter := newFilter(sys, addresses, topics)
+	filter.block = block
+	return filter
+}
+
+// newFilter creates a generic filter that can either filter based on a block hash,
+// or based on range queries. The search criteria needs to be explicitly set.
+func newFilter(sys *FilterSystem, addresses []common.Address, topics [][]common.Hash) *Filter {
+	return &Filter{
+		sys:       sys,
+		addresses: addresses,
+		topics:    topics,
+	}
+}
+
+// Logs searches the blockchain for matching log entries, returning all from the
+// first block that contains matches, updating the start of the filter accordingly.
+func (f *Filter) Logs(ctx context.Context) ([]*types.Log, error) {
+	// If we're doing singleton block filtering, execute and return
+	if f.block != (common.Hash{}) {
+		header, err := f.sys.backend.HeaderByHash(ctx, f.block)
+		if err != nil {
+			return nil, err
+		}
+		if header == nil {
+			return nil, errors.New("unknown block")
+		}
+		return f.blockLogs(ctx, header, false)
+	}
+	// Short-cut if all we care about is pending logs
+	if f.begin == rpc.PendingBlockNumber.Int64() {
+		if f.end != rpc.PendingBlockNumber.Int64() {
+			return nil, errors.New("invalid block range")
+		}
+		return f.pendingLogs()
+	}
+	// Figure out the limits of the filter range
+	header, _ := f.sys.backend.HeaderByNumber(ctx, rpc.LatestBlockNumber)
+	if header == nil {
+		return nil, nil
+	}
+	var (
+		err     error
+		head    = header.Number.Int64()
+		pending = f.end == rpc.PendingBlockNumber.Int64()
+	)
+	resolveSpecial := func(number int64) (int64, error) {
+		var hdr *types.Header
+		switch number {
+		case rpc.LatestBlockNumber.Int64():
+			return head, nil
+		case rpc.PendingBlockNumber.Int64():
+			// we should return head here since we've already captured
+			// that we need to get the pending logs in the pending boolean above
+			return head, nil
+		case rpc.FinalizedBlockNumber.Int64():
+			hdr, _ = f.sys.backend.HeaderByNumber(ctx, rpc.FinalizedBlockNumber)
+			if hdr == nil {
+				return 0, errors.New("finalized header not found")
+			}
+		case rpc.SafeBlockNumber.Int64():
+			hdr, _ = f.sys.backend.HeaderByNumber(ctx, rpc.SafeBlockNumber)
+			if hdr == nil {
+				return 0, errors.New("safe header not found")
+			}
+		default:
+			return number, nil
+		}
+		return hdr.Number.Int64(), nil
+	}
+	if f.begin, err = resolveSpecial(f.begin); err != nil {
+		return nil, err
+	}
+	if f.end, err = resolveSpecial(f.end); err != nil {
+		return nil, err
+	}
+	// Gather all indexed logs, and finish with non indexed ones
+	var (
+		logs           []*types.Log
+		end            = uint64(f.end)
+		size, sections = f.sys.backend.BloomStatus()
+	)
+	if indexed := sections * size; indexed > uint64(f.begin) {
+		if indexed > end {
+			logs, err = f.indexedLogs(ctx, end)
+		} else {
+			logs, err = f.indexedLogs(ctx, indexed-1)
+		}
+		if err != nil {
+			return logs, err
+		}
+	}
+	rest, err := f.unindexedLogs(ctx, end)
+	logs = append(logs, rest...)
+	if pending {
+		pendingLogs, err := f.pendingLogs()
+		if err != nil {
+			return nil, err
+		}
+		logs = append(logs, pendingLogs...)
+	}
+	return logs, err
+}
+
+// indexedLogs returns the logs matching the filter criteria based on the bloom
+// bits indexed available locally or via the network.
+func (f *Filter) indexedLogs(ctx context.Context, end uint64) ([]*types.Log, error) {
+	// Create a matcher session and request servicing from the backend
+	matches := make(chan uint64, 64)
+
+	session, err := f.matcher.Start(ctx, uint64(f.begin), end, matches)
+	if err != nil {
+		return nil, err
+	}
+	defer session.Close()
+
+	f.sys.backend.ServiceFilter(ctx, session)
+
+	// Iterate over the matches until exhausted or context closed
+	var logs []*types.Log
+
+	for {
+		select {
+		case number, ok := <-matches:
+			// Abort if all matches have been fulfilled
+			if !ok {
+				err := session.Error()
+				if err == nil {
+					f.begin = int64(end) + 1
+				}
+				return logs, err
+			}
+			f.begin = int64(number) + 1
+
+			// Retrieve the suggested block and pull any truly matching logs
+			header, err := f.sys.backend.HeaderByNumber(ctx, rpc.BlockNumber(number))
+			if header == nil || err != nil {
+				return logs, err
+			}
+			found, err := f.blockLogs(ctx, header, true)
+			if err != nil {
+				return logs, err
+			}
+			logs = append(logs, found...)
+
+		case <-ctx.Done():
+			return logs, ctx.Err()
+		}
+	}
+}
+
+// unindexedLogs returns the logs matching the filter criteria based on raw block
+// iteration and bloom matching.
+func (f *Filter) unindexedLogs(ctx context.Context, end uint64) ([]*types.Log, error) {
+	var logs []*types.Log
+
+	for ; f.begin <= int64(end); f.begin++ {
+		header, err := f.sys.backend.HeaderByNumber(ctx, rpc.BlockNumber(f.begin))
+		if header == nil || err != nil {
+			return logs, err
+		}
+		found, err := f.blockLogs(ctx, header, false)
+		if err != nil {
+			return logs, err
+		}
+		logs = append(logs, found...)
+	}
+	return logs, nil
+}
+
+// blockLogs returns the logs matching the filter criteria within a single block.
+func (f *Filter) blockLogs(ctx context.Context, header *types.Header, skipBloom bool) ([]*types.Log, error) {
+	// Fast track: no filtering criteria
+	if len(f.addresses) == 0 && len(f.topics) == 0 {
+		list, err := f.sys.cachedGetLogs(ctx, header.Hash(), header.Number.Uint64())
+		if err != nil {
+			return nil, err
+		}
+		return flatten(list), nil
+	} else if skipBloom || bloomFilter(header.Bloom, f.addresses, f.topics) {
+		return f.checkMatches(ctx, header)
+	}
+	return nil, nil
+}
+
+// checkMatches checks if the receipts belonging to the given header contain any log events that
+// match the filter criteria. This function is called when the bloom filter signals a potential match.
+func (f *Filter) checkMatches(ctx context.Context, header *types.Header) ([]*types.Log, error) {
+	logsList, err := f.sys.cachedGetLogs(ctx, header.Hash(), header.Number.Uint64())
+	if err != nil {
+		return nil, err
+	}
+
+	unfiltered := flatten(logsList)
+	logs := filterLogs(unfiltered, nil, nil, f.addresses, f.topics)
+	if len(logs) > 0 {
+		// We have matching logs, check if we need to resolve full logs via the light client
+		if logs[0].TxHash == (common.Hash{}) {
+			receipts, err := f.sys.backend.GetReceipts(ctx, header.Hash())
+			if err != nil {
+				return nil, err
+			}
+			unfiltered = unfiltered[:0]
+			for _, receipt := range receipts {
+				unfiltered = append(unfiltered, receipt.Logs...)
+			}
+			logs = filterLogs(unfiltered, nil, nil, f.addresses, f.topics)
+		}
+		return logs, nil
+	}
+	return nil, nil
+}
+
+// pendingLogs returns the logs matching the filter criteria within the pending block.
+func (f *Filter) pendingLogs() ([]*types.Log, error) {
+	block, receipts := f.sys.backend.PendingBlockAndReceipts()
+	if bloomFilter(block.Bloom(), f.addresses, f.topics) {
+		var unfiltered []*types.Log
+		for _, r := range receipts {
+			unfiltered = append(unfiltered, r.Logs...)
+		}
+		return filterLogs(unfiltered, nil, nil, f.addresses, f.topics), nil
+	}
+	return nil, nil
+}
+
+func includes(addresses []common.Address, a common.Address) bool {
+	for _, addr := range addresses {
+		if addr == a {
+			return true
+		}
+	}
+
+	return false
+}
+
+// filterLogs creates a slice of logs matching the given criteria.
+func filterLogs(logs []*types.Log, fromBlock, toBlock *big.Int, addresses []common.Address, topics [][]common.Hash) []*types.Log {
+	var ret []*types.Log
+Logs:
+	for _, log := range logs {
+		if fromBlock != nil && fromBlock.Int64() >= 0 && fromBlock.Uint64() > log.BlockNumber {
+			continue
+		}
+		if toBlock != nil && toBlock.Int64() >= 0 && toBlock.Uint64() < log.BlockNumber {
+			continue
+		}
+
+		if len(addresses) > 0 && !includes(addresses, log.Address) {
+			continue
+		}
+		// If the to filtered topics is greater than the amount of topics in logs, skip.
+		if len(topics) > len(log.Topics) {
+			continue
+		}
+		for i, sub := range topics {
+			match := len(sub) == 0 // empty rule set == wildcard
+			for _, topic := range sub {
+				if log.Topics[i] == topic {
+					match = true
+					break
+				}
+			}
+			if !match {
+				continue Logs
+			}
+		}
+		ret = append(ret, log)
+	}
+	return ret
+}
+
+func bloomFilter(bloom types.Bloom, addresses []common.Address, topics [][]common.Hash) bool {
+	if len(addresses) > 0 {
+		var included bool
+		for _, addr := range addresses {
+			if types.BloomLookup(bloom, addr) {
+				included = true
+				break
+			}
+		}
+		if !included {
+			return false
+		}
+	}
+
+	for _, sub := range topics {
+		included := len(sub) == 0 // empty rule set == wildcard
+		for _, topic := range sub {
+			if types.BloomLookup(bloom, topic) {
+				included = true
+				break
+			}
+		}
+		if !included {
+			return false
+		}
+	}
+	return true
+}
+
+func flatten(list [][]*types.Log) []*types.Log {
+	var flat []*types.Log
+	for _, logs := range list {
+		flat = append(flat, logs...)
+	}
+	return flat
+}

vendor/github.com/ethereum/go-ethereum/eth/filters/filter_system.go

@@ -0,0 +1,577 @@
+// Copyright 2015 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 filters implements an ethereum filtering system for block,
+// transactions and log events.
+package filters
+
+import (
+	"context"
+	"fmt"
+	"sync"
+	"time"
+
+	"github.com/ethereum/go-ethereum"
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core"
+	"github.com/ethereum/go-ethereum/core/bloombits"
+	"github.com/ethereum/go-ethereum/core/rawdb"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/ethdb"
+	"github.com/ethereum/go-ethereum/event"
+	"github.com/ethereum/go-ethereum/log"
+	"github.com/ethereum/go-ethereum/rpc"
+	lru "github.com/hashicorp/golang-lru"
+)
+
+// Config represents the configuration of the filter system.
+type Config struct {
+	LogCacheSize int           // maximum number of cached blocks (default: 32)
+	Timeout      time.Duration // how long filters stay active (default: 5min)
+}
+
+func (cfg Config) withDefaults() Config {
+	if cfg.Timeout == 0 {
+		cfg.Timeout = 5 * time.Minute
+	}
+	if cfg.LogCacheSize == 0 {
+		cfg.LogCacheSize = 32
+	}
+	return cfg
+}
+
+type Backend interface {
+	ChainDb() ethdb.Database
+	HeaderByNumber(ctx context.Context, blockNr rpc.BlockNumber) (*types.Header, error)
+	HeaderByHash(ctx context.Context, blockHash common.Hash) (*types.Header, error)
+	GetReceipts(ctx context.Context, blockHash common.Hash) (types.Receipts, error)
+	GetLogs(ctx context.Context, blockHash common.Hash, number uint64) ([][]*types.Log, error)
+	PendingBlockAndReceipts() (*types.Block, types.Receipts)
+
+	SubscribeNewTxsEvent(chan<- core.NewTxsEvent) event.Subscription
+	SubscribeChainEvent(ch chan<- core.ChainEvent) event.Subscription
+	SubscribeRemovedLogsEvent(ch chan<- core.RemovedLogsEvent) event.Subscription
+	SubscribeLogsEvent(ch chan<- []*types.Log) event.Subscription
+	SubscribePendingLogsEvent(ch chan<- []*types.Log) event.Subscription
+
+	BloomStatus() (uint64, uint64)
+	ServiceFilter(ctx context.Context, session *bloombits.MatcherSession)
+}
+
+// FilterSystem holds resources shared by all filters.
+type FilterSystem struct {
+	backend   Backend
+	logsCache *lru.Cache
+	cfg       *Config
+}
+
+// NewFilterSystem creates a filter system.
+func NewFilterSystem(backend Backend, config Config) *FilterSystem {
+	config = config.withDefaults()
+
+	cache, err := lru.New(config.LogCacheSize)
+	if err != nil {
+		panic(err)
+	}
+	return &FilterSystem{
+		backend:   backend,
+		logsCache: cache,
+		cfg:       &config,
+	}
+}
+
+// cachedGetLogs loads block logs from the backend and caches the result.
+func (sys *FilterSystem) cachedGetLogs(ctx context.Context, blockHash common.Hash, number uint64) ([][]*types.Log, error) {
+	cached, ok := sys.logsCache.Get(blockHash)
+	if ok {
+		return cached.([][]*types.Log), nil
+	}
+
+	logs, err := sys.backend.GetLogs(ctx, blockHash, number)
+	if err != nil {
+		return nil, err
+	}
+	if logs == nil {
+		return nil, fmt.Errorf("failed to get logs for block #%d (0x%s)", number, blockHash.TerminalString())
+	}
+	sys.logsCache.Add(blockHash, logs)
+	return logs, nil
+}
+
+// Type determines the kind of filter and is used to put the filter in to
+// the correct bucket when added.
+type Type byte
+
+const (
+	// UnknownSubscription indicates an unknown subscription type
+	UnknownSubscription Type = iota
+	// LogsSubscription queries for new or removed (chain reorg) logs
+	LogsSubscription
+	// PendingLogsSubscription queries for logs in pending blocks
+	PendingLogsSubscription
+	// MinedAndPendingLogsSubscription queries for logs in mined and pending blocks.
+	MinedAndPendingLogsSubscription
+	// PendingTransactionsSubscription queries for pending transactions entering
+	// the pending state
+	PendingTransactionsSubscription
+	// BlocksSubscription queries hashes for blocks that are imported
+	BlocksSubscription
+	// LastIndexSubscription keeps track of the last index
+	LastIndexSubscription
+)
+
+const (
+	// txChanSize is the size of channel listening to NewTxsEvent.
+	// The number is referenced from the size of tx pool.
+	txChanSize = 4096
+	// rmLogsChanSize is the size of channel listening to RemovedLogsEvent.
+	rmLogsChanSize = 10
+	// logsChanSize is the size of channel listening to LogsEvent.
+	logsChanSize = 10
+	// chainEvChanSize is the size of channel listening to ChainEvent.
+	chainEvChanSize = 10
+)
+
+type subscription struct {
+	id        rpc.ID
+	typ       Type
+	created   time.Time
+	logsCrit  ethereum.FilterQuery
+	logs      chan []*types.Log
+	txs       chan []*types.Transaction
+	headers   chan *types.Header
+	installed chan struct{} // closed when the filter is installed
+	err       chan error    // closed when the filter is uninstalled
+}
+
+// EventSystem creates subscriptions, processes events and broadcasts them to the
+// subscription which match the subscription criteria.
+type EventSystem struct {
+	backend   Backend
+	sys       *FilterSystem
+	lightMode bool
+	lastHead  *types.Header
+
+	// Subscriptions
+	txsSub         event.Subscription // Subscription for new transaction event
+	logsSub        event.Subscription // Subscription for new log event
+	rmLogsSub      event.Subscription // Subscription for removed log event
+	pendingLogsSub event.Subscription // Subscription for pending log event
+	chainSub       event.Subscription // Subscription for new chain event
+
+	// Channels
+	install       chan *subscription         // install filter for event notification
+	uninstall     chan *subscription         // remove filter for event notification
+	txsCh         chan core.NewTxsEvent      // Channel to receive new transactions event
+	logsCh        chan []*types.Log          // Channel to receive new log event
+	pendingLogsCh chan []*types.Log          // Channel to receive new log event
+	rmLogsCh      chan core.RemovedLogsEvent // Channel to receive removed log event
+	chainCh       chan core.ChainEvent       // Channel to receive new chain event
+}
+
+// NewEventSystem creates a new manager that listens for event on the given mux,
+// parses and filters them. It uses the all map to retrieve filter changes. The
+// work loop holds its own index that is used to forward events to filters.
+//
+// The returned manager has a loop that needs to be stopped with the Stop function
+// or by stopping the given mux.
+func NewEventSystem(sys *FilterSystem, lightMode bool) *EventSystem {
+	m := &EventSystem{
+		sys:           sys,
+		backend:       sys.backend,
+		lightMode:     lightMode,
+		install:       make(chan *subscription),
+		uninstall:     make(chan *subscription),
+		txsCh:         make(chan core.NewTxsEvent, txChanSize),
+		logsCh:        make(chan []*types.Log, logsChanSize),
+		rmLogsCh:      make(chan core.RemovedLogsEvent, rmLogsChanSize),
+		pendingLogsCh: make(chan []*types.Log, logsChanSize),
+		chainCh:       make(chan core.ChainEvent, chainEvChanSize),
+	}
+
+	// Subscribe events
+	m.txsSub = m.backend.SubscribeNewTxsEvent(m.txsCh)
+	m.logsSub = m.backend.SubscribeLogsEvent(m.logsCh)
+	m.rmLogsSub = m.backend.SubscribeRemovedLogsEvent(m.rmLogsCh)
+	m.chainSub = m.backend.SubscribeChainEvent(m.chainCh)
+	m.pendingLogsSub = m.backend.SubscribePendingLogsEvent(m.pendingLogsCh)
+
+	// Make sure none of the subscriptions are empty
+	if m.txsSub == nil || m.logsSub == nil || m.rmLogsSub == nil || m.chainSub == nil || m.pendingLogsSub == nil {
+		log.Crit("Subscribe for event system failed")
+	}
+
+	go m.eventLoop()
+	return m
+}
+
+// Subscription is created when the client registers itself for a particular event.
+type Subscription struct {
+	ID        rpc.ID
+	f         *subscription
+	es        *EventSystem
+	unsubOnce sync.Once
+}
+
+// Err returns a channel that is closed when unsubscribed.
+func (sub *Subscription) Err() <-chan error {
+	return sub.f.err
+}
+
+// Unsubscribe uninstalls the subscription from the event broadcast loop.
+func (sub *Subscription) Unsubscribe() {
+	sub.unsubOnce.Do(func() {
+	uninstallLoop:
+		for {
+			// write uninstall request and consume logs/hashes. This prevents
+			// the eventLoop broadcast method to deadlock when writing to the
+			// filter event channel while the subscription loop is waiting for
+			// this method to return (and thus not reading these events).
+			select {
+			case sub.es.uninstall <- sub.f:
+				break uninstallLoop
+			case <-sub.f.logs:
+			case <-sub.f.txs:
+			case <-sub.f.headers:
+			}
+		}
+
+		// wait for filter to be uninstalled in work loop before returning
+		// this ensures that the manager won't use the event channel which
+		// will probably be closed by the client asap after this method returns.
+		<-sub.Err()
+	})
+}
+
+// subscribe installs the subscription in the event broadcast loop.
+func (es *EventSystem) subscribe(sub *subscription) *Subscription {
+	es.install <- sub
+	<-sub.installed
+	return &Subscription{ID: sub.id, f: sub, es: es}
+}
+
+// SubscribeLogs creates a subscription that will write all logs matching the
+// given criteria to the given logs channel. Default value for the from and to
+// block is "latest". If the fromBlock > toBlock an error is returned.
+func (es *EventSystem) SubscribeLogs(crit ethereum.FilterQuery, logs chan []*types.Log) (*Subscription, error) {
+	var from, to rpc.BlockNumber
+	if crit.FromBlock == nil {
+		from = rpc.LatestBlockNumber
+	} else {
+		from = rpc.BlockNumber(crit.FromBlock.Int64())
+	}
+	if crit.ToBlock == nil {
+		to = rpc.LatestBlockNumber
+	} else {
+		to = rpc.BlockNumber(crit.ToBlock.Int64())
+	}
+
+	// only interested in pending logs
+	if from == rpc.PendingBlockNumber && to == rpc.PendingBlockNumber {
+		return es.subscribePendingLogs(crit, logs), nil
+	}
+	// only interested in new mined logs
+	if from == rpc.LatestBlockNumber && to == rpc.LatestBlockNumber {
+		return es.subscribeLogs(crit, logs), nil
+	}
+	// only interested in mined logs within a specific block range
+	if from >= 0 && to >= 0 && to >= from {
+		return es.subscribeLogs(crit, logs), nil
+	}
+	// interested in mined logs from a specific block number, new logs and pending logs
+	if from >= rpc.LatestBlockNumber && to == rpc.PendingBlockNumber {
+		return es.subscribeMinedPendingLogs(crit, logs), nil
+	}
+	// interested in logs from a specific block number to new mined blocks
+	if from >= 0 && to == rpc.LatestBlockNumber {
+		return es.subscribeLogs(crit, logs), nil
+	}
+	return nil, fmt.Errorf("invalid from and to block combination: from > to")
+}
+
+// subscribeMinedPendingLogs creates a subscription that returned mined and
+// pending logs that match the given criteria.
+func (es *EventSystem) subscribeMinedPendingLogs(crit ethereum.FilterQuery, logs chan []*types.Log) *Subscription {
+	sub := &subscription{
+		id:        rpc.NewID(),
+		typ:       MinedAndPendingLogsSubscription,
+		logsCrit:  crit,
+		created:   time.Now(),
+		logs:      logs,
+		txs:       make(chan []*types.Transaction),
+		headers:   make(chan *types.Header),
+		installed: make(chan struct{}),
+		err:       make(chan error),
+	}
+	return es.subscribe(sub)
+}
+
+// subscribeLogs creates a subscription that will write all logs matching the
+// given criteria to the given logs channel.
+func (es *EventSystem) subscribeLogs(crit ethereum.FilterQuery, logs chan []*types.Log) *Subscription {
+	sub := &subscription{
+		id:        rpc.NewID(),
+		typ:       LogsSubscription,
+		logsCrit:  crit,
+		created:   time.Now(),
+		logs:      logs,
+		txs:       make(chan []*types.Transaction),
+		headers:   make(chan *types.Header),
+		installed: make(chan struct{}),
+		err:       make(chan error),
+	}
+	return es.subscribe(sub)
+}
+
+// subscribePendingLogs creates a subscription that writes contract event logs for
+// transactions that enter the transaction pool.
+func (es *EventSystem) subscribePendingLogs(crit ethereum.FilterQuery, logs chan []*types.Log) *Subscription {
+	sub := &subscription{
+		id:        rpc.NewID(),
+		typ:       PendingLogsSubscription,
+		logsCrit:  crit,
+		created:   time.Now(),
+		logs:      logs,
+		txs:       make(chan []*types.Transaction),
+		headers:   make(chan *types.Header),
+		installed: make(chan struct{}),
+		err:       make(chan error),
+	}
+	return es.subscribe(sub)
+}
+
+// SubscribeNewHeads creates a subscription that writes the header of a block that is
+// imported in the chain.
+func (es *EventSystem) SubscribeNewHeads(headers chan *types.Header) *Subscription {
+	sub := &subscription{
+		id:        rpc.NewID(),
+		typ:       BlocksSubscription,
+		created:   time.Now(),
+		logs:      make(chan []*types.Log),
+		txs:       make(chan []*types.Transaction),
+		headers:   headers,
+		installed: make(chan struct{}),
+		err:       make(chan error),
+	}
+	return es.subscribe(sub)
+}
+
+// SubscribePendingTxs creates a subscription that writes transactions for
+// transactions that enter the transaction pool.
+func (es *EventSystem) SubscribePendingTxs(txs chan []*types.Transaction) *Subscription {
+	sub := &subscription{
+		id:        rpc.NewID(),
+		typ:       PendingTransactionsSubscription,
+		created:   time.Now(),
+		logs:      make(chan []*types.Log),
+		txs:       txs,
+		headers:   make(chan *types.Header),
+		installed: make(chan struct{}),
+		err:       make(chan error),
+	}
+	return es.subscribe(sub)
+}
+
+type filterIndex map[Type]map[rpc.ID]*subscription
+
+func (es *EventSystem) handleLogs(filters filterIndex, ev []*types.Log) {
+	if len(ev) == 0 {
+		return
+	}
+	for _, f := range filters[LogsSubscription] {
+		matchedLogs := filterLogs(ev, f.logsCrit.FromBlock, f.logsCrit.ToBlock, f.logsCrit.Addresses, f.logsCrit.Topics)
+		if len(matchedLogs) > 0 {
+			f.logs <- matchedLogs
+		}
+	}
+}
+
+func (es *EventSystem) handlePendingLogs(filters filterIndex, ev []*types.Log) {
+	if len(ev) == 0 {
+		return
+	}
+	for _, f := range filters[PendingLogsSubscription] {
+		matchedLogs := filterLogs(ev, nil, f.logsCrit.ToBlock, f.logsCrit.Addresses, f.logsCrit.Topics)
+		if len(matchedLogs) > 0 {
+			f.logs <- matchedLogs
+		}
+	}
+}
+
+func (es *EventSystem) handleRemovedLogs(filters filterIndex, ev core.RemovedLogsEvent) {
+	for _, f := range filters[LogsSubscription] {
+		matchedLogs := filterLogs(ev.Logs, f.logsCrit.FromBlock, f.logsCrit.ToBlock, f.logsCrit.Addresses, f.logsCrit.Topics)
+		if len(matchedLogs) > 0 {
+			f.logs <- matchedLogs
+		}
+	}
+}
+
+func (es *EventSystem) handleTxsEvent(filters filterIndex, ev core.NewTxsEvent) {
+	for _, f := range filters[PendingTransactionsSubscription] {
+		f.txs <- ev.Txs
+	}
+}
+
+func (es *EventSystem) handleChainEvent(filters filterIndex, ev core.ChainEvent) {
+	for _, f := range filters[BlocksSubscription] {
+		f.headers <- ev.Block.Header()
+	}
+	if es.lightMode && len(filters[LogsSubscription]) > 0 {
+		es.lightFilterNewHead(ev.Block.Header(), func(header *types.Header, remove bool) {
+			for _, f := range filters[LogsSubscription] {
+				if matchedLogs := es.lightFilterLogs(header, f.logsCrit.Addresses, f.logsCrit.Topics, remove); len(matchedLogs) > 0 {
+					f.logs <- matchedLogs
+				}
+			}
+		})
+	}
+}
+
+func (es *EventSystem) lightFilterNewHead(newHeader *types.Header, callBack func(*types.Header, bool)) {
+	oldh := es.lastHead
+	es.lastHead = newHeader
+	if oldh == nil {
+		return
+	}
+	newh := newHeader
+	// find common ancestor, create list of rolled back and new block hashes
+	var oldHeaders, newHeaders []*types.Header
+	for oldh.Hash() != newh.Hash() {
+		if oldh.Number.Uint64() >= newh.Number.Uint64() {
+			oldHeaders = append(oldHeaders, oldh)
+			oldh = rawdb.ReadHeader(es.backend.ChainDb(), oldh.ParentHash, oldh.Number.Uint64()-1)
+		}
+		if oldh.Number.Uint64() < newh.Number.Uint64() {
+			newHeaders = append(newHeaders, newh)
+			newh = rawdb.ReadHeader(es.backend.ChainDb(), newh.ParentHash, newh.Number.Uint64()-1)
+			if newh == nil {
+				// happens when CHT syncing, nothing to do
+				newh = oldh
+			}
+		}
+	}
+	// roll back old blocks
+	for _, h := range oldHeaders {
+		callBack(h, true)
+	}
+	// check new blocks (array is in reverse order)
+	for i := len(newHeaders) - 1; i >= 0; i-- {
+		callBack(newHeaders[i], false)
+	}
+}
+
+// filter logs of a single header in light client mode
+func (es *EventSystem) lightFilterLogs(header *types.Header, addresses []common.Address, topics [][]common.Hash, remove bool) []*types.Log {
+	if bloomFilter(header.Bloom, addresses, topics) {
+		// Get the logs of the block
+		ctx, cancel := context.WithTimeout(context.Background(), time.Second*5)
+		defer cancel()
+		logsList, err := es.sys.cachedGetLogs(ctx, header.Hash(), header.Number.Uint64())
+		if err != nil {
+			return nil
+		}
+		var unfiltered []*types.Log
+		for _, logs := range logsList {
+			for _, log := range logs {
+				logcopy := *log
+				logcopy.Removed = remove
+				unfiltered = append(unfiltered, &logcopy)
+			}
+		}
+		logs := filterLogs(unfiltered, nil, nil, addresses, topics)
+		if len(logs) > 0 && logs[0].TxHash == (common.Hash{}) {
+			// We have matching but non-derived logs
+			receipts, err := es.backend.GetReceipts(ctx, header.Hash())
+			if err != nil {
+				return nil
+			}
+			unfiltered = unfiltered[:0]
+			for _, receipt := range receipts {
+				for _, log := range receipt.Logs {
+					logcopy := *log
+					logcopy.Removed = remove
+					unfiltered = append(unfiltered, &logcopy)
+				}
+			}
+			logs = filterLogs(unfiltered, nil, nil, addresses, topics)
+		}
+		return logs
+	}
+	return nil
+}
+
+// eventLoop (un)installs filters and processes mux events.
+func (es *EventSystem) eventLoop() {
+	// Ensure all subscriptions get cleaned up
+	defer func() {
+		es.txsSub.Unsubscribe()
+		es.logsSub.Unsubscribe()
+		es.rmLogsSub.Unsubscribe()
+		es.pendingLogsSub.Unsubscribe()
+		es.chainSub.Unsubscribe()
+	}()
+
+	index := make(filterIndex)
+	for i := UnknownSubscription; i < LastIndexSubscription; i++ {
+		index[i] = make(map[rpc.ID]*subscription)
+	}
+
+	for {
+		select {
+		case ev := <-es.txsCh:
+			es.handleTxsEvent(index, ev)
+		case ev := <-es.logsCh:
+			es.handleLogs(index, ev)
+		case ev := <-es.rmLogsCh:
+			es.handleRemovedLogs(index, ev)
+		case ev := <-es.pendingLogsCh:
+			es.handlePendingLogs(index, ev)
+		case ev := <-es.chainCh:
+			es.handleChainEvent(index, ev)
+
+		case f := <-es.install:
+			if f.typ == MinedAndPendingLogsSubscription {
+				// the type are logs and pending logs subscriptions
+				index[LogsSubscription][f.id] = f
+				index[PendingLogsSubscription][f.id] = f
+			} else {
+				index[f.typ][f.id] = f
+			}
+			close(f.installed)
+
+		case f := <-es.uninstall:
+			if f.typ == MinedAndPendingLogsSubscription {
+				// the type are logs and pending logs subscriptions
+				delete(index[LogsSubscription], f.id)
+				delete(index[PendingLogsSubscription], f.id)
+			} else {
+				delete(index[f.typ], f.id)
+			}
+			close(f.err)
+
+		// System stopped
+		case <-es.txsSub.Err():
+			return
+		case <-es.logsSub.Err():
+			return
+		case <-es.rmLogsSub.Err():
+			return
+		case <-es.chainSub.Err():
+			return
+		}
+	}
+}

vendor/github.com/ethereum/go-ethereum/eth/tracers/logger/access_list_tracer.go

@@ -0,0 +1,184 @@
+// Copyright 2021 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 logger
+
+import (
+	"math/big"
+	"time"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/core/vm"
+)
+
+// accessList is an accumulator for the set of accounts and storage slots an EVM
+// contract execution touches.
+type accessList map[common.Address]accessListSlots
+
+// accessListSlots is an accumulator for the set of storage slots within a single
+// contract that an EVM contract execution touches.
+type accessListSlots map[common.Hash]struct{}
+
+// newAccessList creates a new accessList.
+func newAccessList() accessList {
+	return make(map[common.Address]accessListSlots)
+}
+
+// addAddress adds an address to the accesslist.
+func (al accessList) addAddress(address common.Address) {
+	// Set address if not previously present
+	if _, present := al[address]; !present {
+		al[address] = make(map[common.Hash]struct{})
+	}
+}
+
+// addSlot adds a storage slot to the accesslist.
+func (al accessList) addSlot(address common.Address, slot common.Hash) {
+	// Set address if not previously present
+	al.addAddress(address)
+
+	// Set the slot on the surely existent storage set
+	al[address][slot] = struct{}{}
+}
+
+// equal checks if the content of the current access list is the same as the
+// content of the other one.
+func (al accessList) equal(other accessList) bool {
+	// Cross reference the accounts first
+	if len(al) != len(other) {
+		return false
+	}
+	// Given that len(al) == len(other), we only need to check that
+	// all the items from al are in other.
+	for addr := range al {
+		if _, ok := other[addr]; !ok {
+			return false
+		}
+	}
+
+	// Accounts match, cross reference the storage slots too
+	for addr, slots := range al {
+		otherslots := other[addr]
+
+		if len(slots) != len(otherslots) {
+			return false
+		}
+		// Given that len(slots) == len(otherslots), we only need to check that
+		// all the items from slots are in otherslots.
+		for hash := range slots {
+			if _, ok := otherslots[hash]; !ok {
+				return false
+			}
+		}
+	}
+	return true
+}
+
+// accesslist converts the accesslist to a types.AccessList.
+func (al accessList) accessList() types.AccessList {
+	acl := make(types.AccessList, 0, len(al))
+	for addr, slots := range al {
+		tuple := types.AccessTuple{Address: addr, StorageKeys: []common.Hash{}}
+		for slot := range slots {
+			tuple.StorageKeys = append(tuple.StorageKeys, slot)
+		}
+		acl = append(acl, tuple)
+	}
+	return acl
+}
+
+// AccessListTracer is a tracer that accumulates touched accounts and storage
+// slots into an internal set.
+type AccessListTracer struct {
+	excl map[common.Address]struct{} // Set of account to exclude from the list
+	list accessList                  // Set of accounts and storage slots touched
+}
+
+// NewAccessListTracer creates a new tracer that can generate AccessLists.
+// An optional AccessList can be specified to occupy slots and addresses in
+// the resulting accesslist.
+func NewAccessListTracer(acl types.AccessList, from, to common.Address, precompiles []common.Address) *AccessListTracer {
+	excl := map[common.Address]struct{}{
+		from: {}, to: {},
+	}
+	for _, addr := range precompiles {
+		excl[addr] = struct{}{}
+	}
+	list := newAccessList()
+	for _, al := range acl {
+		if _, ok := excl[al.Address]; !ok {
+			list.addAddress(al.Address)
+		}
+		for _, slot := range al.StorageKeys {
+			list.addSlot(al.Address, slot)
+		}
+	}
+	return &AccessListTracer{
+		excl: excl,
+		list: list,
+	}
+}
+
+func (a *AccessListTracer) CaptureStart(env *vm.EVM, from common.Address, to common.Address, create bool, input []byte, gas uint64, value *big.Int) {
+}
+
+// CaptureState captures all opcodes that touch storage or addresses and adds them to the accesslist.
+func (a *AccessListTracer) CaptureState(pc uint64, op vm.OpCode, gas, cost uint64, scope *vm.ScopeContext, rData []byte, depth int, err error) {
+	stack := scope.Stack
+	stackData := stack.Data()
+	stackLen := len(stackData)
+	if (op == vm.SLOAD || op == vm.SSTORE) && stackLen >= 1 {
+		slot := common.Hash(stackData[stackLen-1].Bytes32())
+		a.list.addSlot(scope.Contract.Address(), slot)
+	}
+	if (op == vm.EXTCODECOPY || op == vm.EXTCODEHASH || op == vm.EXTCODESIZE || op == vm.BALANCE || op == vm.SELFDESTRUCT) && stackLen >= 1 {
+		addr := common.Address(stackData[stackLen-1].Bytes20())
+		if _, ok := a.excl[addr]; !ok {
+			a.list.addAddress(addr)
+		}
+	}
+	if (op == vm.DELEGATECALL || op == vm.CALL || op == vm.STATICCALL || op == vm.CALLCODE) && stackLen >= 5 {
+		addr := common.Address(stackData[stackLen-2].Bytes20())
+		if _, ok := a.excl[addr]; !ok {
+			a.list.addAddress(addr)
+		}
+	}
+}
+
+func (*AccessListTracer) CaptureFault(pc uint64, op vm.OpCode, gas, cost uint64, scope *vm.ScopeContext, depth int, err error) {
+}
+
+func (*AccessListTracer) CaptureEnd(output []byte, gasUsed uint64, t time.Duration, err error) {}
+
+func (*AccessListTracer) CaptureEnter(typ vm.OpCode, from common.Address, to common.Address, input []byte, gas uint64, value *big.Int) {
+}
+
+func (*AccessListTracer) CaptureExit(output []byte, gasUsed uint64, err error) {}
+
+func (*AccessListTracer) CaptureTxStart(gasLimit uint64) {}
+
+func (*AccessListTracer) CaptureTxEnd(restGas uint64) {}
+
+// AccessList returns the current accesslist maintained by the tracer.
+func (a *AccessListTracer) AccessList() types.AccessList {
+	return a.list.accessList()
+}
+
+// Equal returns if the content of two access list traces are equal.
+func (a *AccessListTracer) Equal(other *AccessListTracer) bool {
+	return a.list.equal(other.list)
+}

vendor/github.com/ethereum/go-ethereum/eth/tracers/logger/gen_structlog.go

@@ -0,0 +1,110 @@
+// Code generated by github.com/fjl/gencodec. DO NOT EDIT.
+
+package logger
+
+import (
+	"encoding/json"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/common/hexutil"
+	"github.com/ethereum/go-ethereum/common/math"
+	"github.com/ethereum/go-ethereum/core/vm"
+	"github.com/holiman/uint256"
+)
+
+var _ = (*structLogMarshaling)(nil)
+
+// MarshalJSON marshals as JSON.
+func (s StructLog) MarshalJSON() ([]byte, error) {
+	type StructLog struct {
+		Pc            uint64                      `json:"pc"`
+		Op            vm.OpCode                   `json:"op"`
+		Gas           math.HexOrDecimal64         `json:"gas"`
+		GasCost       math.HexOrDecimal64         `json:"gasCost"`
+		Memory        hexutil.Bytes               `json:"memory,omitempty"`
+		MemorySize    int                         `json:"memSize"`
+		Stack         []uint256.Int               `json:"stack"`
+		ReturnData    hexutil.Bytes               `json:"returnData,omitempty"`
+		Storage       map[common.Hash]common.Hash `json:"-"`
+		Depth         int                         `json:"depth"`
+		RefundCounter uint64                      `json:"refund"`
+		Err           error                       `json:"-"`
+		OpName        string                      `json:"opName"`
+		ErrorString   string                      `json:"error,omitempty"`
+	}
+	var enc StructLog
+	enc.Pc = s.Pc
+	enc.Op = s.Op
+	enc.Gas = math.HexOrDecimal64(s.Gas)
+	enc.GasCost = math.HexOrDecimal64(s.GasCost)
+	enc.Memory = s.Memory
+	enc.MemorySize = s.MemorySize
+	enc.Stack = s.Stack
+	enc.ReturnData = s.ReturnData
+	enc.Storage = s.Storage
+	enc.Depth = s.Depth
+	enc.RefundCounter = s.RefundCounter
+	enc.Err = s.Err
+	enc.OpName = s.OpName()
+	enc.ErrorString = s.ErrorString()
+	return json.Marshal(&enc)
+}
+
+// UnmarshalJSON unmarshals from JSON.
+func (s *StructLog) UnmarshalJSON(input []byte) error {
+	type StructLog struct {
+		Pc            *uint64                     `json:"pc"`
+		Op            *vm.OpCode                  `json:"op"`
+		Gas           *math.HexOrDecimal64        `json:"gas"`
+		GasCost       *math.HexOrDecimal64        `json:"gasCost"`
+		Memory        *hexutil.Bytes              `json:"memory,omitempty"`
+		MemorySize    *int                        `json:"memSize"`
+		Stack         []uint256.Int               `json:"stack"`
+		ReturnData    *hexutil.Bytes              `json:"returnData,omitempty"`
+		Storage       map[common.Hash]common.Hash `json:"-"`
+		Depth         *int                        `json:"depth"`
+		RefundCounter *uint64                     `json:"refund"`
+		Err           error                       `json:"-"`
+	}
+	var dec StructLog
+	if err := json.Unmarshal(input, &dec); err != nil {
+		return err
+	}
+	if dec.Pc != nil {
+		s.Pc = *dec.Pc
+	}
+	if dec.Op != nil {
+		s.Op = *dec.Op
+	}
+	if dec.Gas != nil {
+		s.Gas = uint64(*dec.Gas)
+	}
+	if dec.GasCost != nil {
+		s.GasCost = uint64(*dec.GasCost)
+	}
+	if dec.Memory != nil {
+		s.Memory = *dec.Memory
+	}
+	if dec.MemorySize != nil {
+		s.MemorySize = *dec.MemorySize
+	}
+	if dec.Stack != nil {
+		s.Stack = dec.Stack
+	}
+	if dec.ReturnData != nil {
+		s.ReturnData = *dec.ReturnData
+	}
+	if dec.Storage != nil {
+		s.Storage = dec.Storage
+	}
+	if dec.Depth != nil {
+		s.Depth = *dec.Depth
+	}
+	if dec.RefundCounter != nil {
+		s.RefundCounter = *dec.RefundCounter
+	}
+	if dec.Err != nil {
+		s.Err = dec.Err
+	}
+	return nil
+}

vendor/github.com/ethereum/go-ethereum/eth/tracers/logger/logger.go

@@ -0,0 +1,464 @@
+// Copyright 2021 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 logger
+
+import (
+	"encoding/hex"
+	"encoding/json"
+	"fmt"
+	"io"
+	"math/big"
+	"strings"
+	"sync/atomic"
+	"time"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/common/hexutil"
+	"github.com/ethereum/go-ethereum/common/math"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/core/vm"
+	"github.com/ethereum/go-ethereum/params"
+	"github.com/holiman/uint256"
+)
+
+// Storage represents a contract's storage.
+type Storage map[common.Hash]common.Hash
+
+// Copy duplicates the current storage.
+func (s Storage) Copy() Storage {
+	cpy := make(Storage, len(s))
+	for key, value := range s {
+		cpy[key] = value
+	}
+	return cpy
+}
+
+// Config are the configuration options for structured logger the EVM
+type Config struct {
+	EnableMemory     bool // enable memory capture
+	DisableStack     bool // disable stack capture
+	DisableStorage   bool // disable storage capture
+	EnableReturnData bool // enable return data capture
+	Debug            bool // print output during capture end
+	Limit            int  // maximum length of output, but zero means unlimited
+	// Chain overrides, can be used to execute a trace using future fork rules
+	Overrides *params.ChainConfig `json:"overrides,omitempty"`
+}
+
+//go:generate go run github.com/fjl/gencodec -type StructLog -field-override structLogMarshaling -out gen_structlog.go
+
+// StructLog is emitted to the EVM each cycle and lists information about the current internal state
+// prior to the execution of the statement.
+type StructLog struct {
+	Pc            uint64                      `json:"pc"`
+	Op            vm.OpCode                   `json:"op"`
+	Gas           uint64                      `json:"gas"`
+	GasCost       uint64                      `json:"gasCost"`
+	Memory        []byte                      `json:"memory,omitempty"`
+	MemorySize    int                         `json:"memSize"`
+	Stack         []uint256.Int               `json:"stack"`
+	ReturnData    []byte                      `json:"returnData,omitempty"`
+	Storage       map[common.Hash]common.Hash `json:"-"`
+	Depth         int                         `json:"depth"`
+	RefundCounter uint64                      `json:"refund"`
+	Err           error                       `json:"-"`
+}
+
+// overrides for gencodec
+type structLogMarshaling struct {
+	Gas         math.HexOrDecimal64
+	GasCost     math.HexOrDecimal64
+	Memory      hexutil.Bytes
+	ReturnData  hexutil.Bytes
+	OpName      string `json:"opName"`          // adds call to OpName() in MarshalJSON
+	ErrorString string `json:"error,omitempty"` // adds call to ErrorString() in MarshalJSON
+}
+
+// OpName formats the operand name in a human-readable format.
+func (s *StructLog) OpName() string {
+	return s.Op.String()
+}
+
+// ErrorString formats the log's error as a string.
+func (s *StructLog) ErrorString() string {
+	if s.Err != nil {
+		return s.Err.Error()
+	}
+	return ""
+}
+
+// StructLogger is an EVM state logger and implements EVMLogger.
+//
+// StructLogger can capture state based on the given Log configuration and also keeps
+// a track record of modified storage which is used in reporting snapshots of the
+// contract their storage.
+type StructLogger struct {
+	cfg Config
+	env *vm.EVM
+
+	storage  map[common.Address]Storage
+	logs     []StructLog
+	output   []byte
+	err      error
+	gasLimit uint64
+	usedGas  uint64
+
+	interrupt uint32 // Atomic flag to signal execution interruption
+	reason    error  // Textual reason for the interruption
+}
+
+// NewStructLogger returns a new logger
+func NewStructLogger(cfg *Config) *StructLogger {
+	logger := &StructLogger{
+		storage: make(map[common.Address]Storage),
+	}
+	if cfg != nil {
+		logger.cfg = *cfg
+	}
+	return logger
+}
+
+// Reset clears the data held by the logger.
+func (l *StructLogger) Reset() {
+	l.storage = make(map[common.Address]Storage)
+	l.output = make([]byte, 0)
+	l.logs = l.logs[:0]
+	l.err = nil
+}
+
+// CaptureStart implements the EVMLogger interface to initialize the tracing operation.
+func (l *StructLogger) CaptureStart(env *vm.EVM, from common.Address, to common.Address, create bool, input []byte, gas uint64, value *big.Int) {
+	l.env = env
+}
+
+// CaptureState logs a new structured log message and pushes it out to the environment
+//
+// CaptureState also tracks SLOAD/SSTORE ops to track storage change.
+func (l *StructLogger) CaptureState(pc uint64, op vm.OpCode, gas, cost uint64, scope *vm.ScopeContext, rData []byte, depth int, err error) {
+	// If tracing was interrupted, set the error and stop
+	if atomic.LoadUint32(&l.interrupt) > 0 {
+		l.env.Cancel()
+		return
+	}
+	// check if already accumulated the specified number of logs
+	if l.cfg.Limit != 0 && l.cfg.Limit <= len(l.logs) {
+		return
+	}
+
+	memory := scope.Memory
+	stack := scope.Stack
+	contract := scope.Contract
+	// Copy a snapshot of the current memory state to a new buffer
+	var mem []byte
+	if l.cfg.EnableMemory {
+		mem = make([]byte, len(memory.Data()))
+		copy(mem, memory.Data())
+	}
+	// Copy a snapshot of the current stack state to a new buffer
+	var stck []uint256.Int
+	if !l.cfg.DisableStack {
+		stck = make([]uint256.Int, len(stack.Data()))
+		for i, item := range stack.Data() {
+			stck[i] = item
+		}
+	}
+	stackData := stack.Data()
+	stackLen := len(stackData)
+	// Copy a snapshot of the current storage to a new container
+	var storage Storage
+	if !l.cfg.DisableStorage && (op == vm.SLOAD || op == vm.SSTORE) {
+		// initialise new changed values storage container for this contract
+		// if not present.
+		if l.storage[contract.Address()] == nil {
+			l.storage[contract.Address()] = make(Storage)
+		}
+		// capture SLOAD opcodes and record the read entry in the local storage
+		if op == vm.SLOAD && stackLen >= 1 {
+			var (
+				address = common.Hash(stackData[stackLen-1].Bytes32())
+				value   = l.env.StateDB.GetState(contract.Address(), address)
+			)
+			l.storage[contract.Address()][address] = value
+			storage = l.storage[contract.Address()].Copy()
+		} else if op == vm.SSTORE && stackLen >= 2 {
+			// capture SSTORE opcodes and record the written entry in the local storage.
+			var (
+				value   = common.Hash(stackData[stackLen-2].Bytes32())
+				address = common.Hash(stackData[stackLen-1].Bytes32())
+			)
+			l.storage[contract.Address()][address] = value
+			storage = l.storage[contract.Address()].Copy()
+		}
+	}
+	var rdata []byte
+	if l.cfg.EnableReturnData {
+		rdata = make([]byte, len(rData))
+		copy(rdata, rData)
+	}
+	// create a new snapshot of the EVM.
+	log := StructLog{pc, op, gas, cost, mem, memory.Len(), stck, rdata, storage, depth, l.env.StateDB.GetRefund(), err}
+	l.logs = append(l.logs, log)
+}
+
+// CaptureFault implements the EVMLogger interface to trace an execution fault
+// while running an opcode.
+func (l *StructLogger) CaptureFault(pc uint64, op vm.OpCode, gas, cost uint64, scope *vm.ScopeContext, depth int, err error) {
+}
+
+// CaptureEnd is called after the call finishes to finalize the tracing.
+func (l *StructLogger) CaptureEnd(output []byte, gasUsed uint64, t time.Duration, err error) {
+	l.output = output
+	l.err = err
+	if l.cfg.Debug {
+		fmt.Printf("%#x\n", output)
+		if err != nil {
+			fmt.Printf(" error: %v\n", err)
+		}
+	}
+}
+
+func (l *StructLogger) CaptureEnter(typ vm.OpCode, from common.Address, to common.Address, input []byte, gas uint64, value *big.Int) {
+}
+
+func (l *StructLogger) CaptureExit(output []byte, gasUsed uint64, err error) {
+}
+
+func (l *StructLogger) GetResult() (json.RawMessage, error) {
+	// Tracing aborted
+	if l.reason != nil {
+		return nil, l.reason
+	}
+	failed := l.err != nil
+	returnData := common.CopyBytes(l.output)
+	// Return data when successful and revert reason when reverted, otherwise empty.
+	returnVal := fmt.Sprintf("%x", returnData)
+	if failed && l.err != vm.ErrExecutionReverted {
+		returnVal = ""
+	}
+	return json.Marshal(&ExecutionResult{
+		Gas:         l.usedGas,
+		Failed:      failed,
+		ReturnValue: returnVal,
+		StructLogs:  formatLogs(l.StructLogs()),
+	})
+}
+
+// Stop terminates execution of the tracer at the first opportune moment.
+func (l *StructLogger) Stop(err error) {
+	l.reason = err
+	atomic.StoreUint32(&l.interrupt, 1)
+}
+
+func (l *StructLogger) CaptureTxStart(gasLimit uint64) {
+	l.gasLimit = gasLimit
+}
+
+func (l *StructLogger) CaptureTxEnd(restGas uint64) {
+	l.usedGas = l.gasLimit - restGas
+}
+
+// StructLogs returns the captured log entries.
+func (l *StructLogger) StructLogs() []StructLog { return l.logs }
+
+// Error returns the VM error captured by the trace.
+func (l *StructLogger) Error() error { return l.err }
+
+// Output returns the VM return value captured by the trace.
+func (l *StructLogger) Output() []byte { return l.output }
+
+// WriteTrace writes a formatted trace to the given writer
+func WriteTrace(writer io.Writer, logs []StructLog) {
+	for _, log := range logs {
+		fmt.Fprintf(writer, "%-16spc=%08d gas=%v cost=%v", log.Op, log.Pc, log.Gas, log.GasCost)
+		if log.Err != nil {
+			fmt.Fprintf(writer, " ERROR: %v", log.Err)
+		}
+		fmt.Fprintln(writer)
+
+		if len(log.Stack) > 0 {
+			fmt.Fprintln(writer, "Stack:")
+			for i := len(log.Stack) - 1; i >= 0; i-- {
+				fmt.Fprintf(writer, "%08d  %s\n", len(log.Stack)-i-1, log.Stack[i].Hex())
+			}
+		}
+		if len(log.Memory) > 0 {
+			fmt.Fprintln(writer, "Memory:")
+			fmt.Fprint(writer, hex.Dump(log.Memory))
+		}
+		if len(log.Storage) > 0 {
+			fmt.Fprintln(writer, "Storage:")
+			for h, item := range log.Storage {
+				fmt.Fprintf(writer, "%x: %x\n", h, item)
+			}
+		}
+		if len(log.ReturnData) > 0 {
+			fmt.Fprintln(writer, "ReturnData:")
+			fmt.Fprint(writer, hex.Dump(log.ReturnData))
+		}
+		fmt.Fprintln(writer)
+	}
+}
+
+// WriteLogs writes vm logs in a readable format to the given writer
+func WriteLogs(writer io.Writer, logs []*types.Log) {
+	for _, log := range logs {
+		fmt.Fprintf(writer, "LOG%d: %x bn=%d txi=%x\n", len(log.Topics), log.Address, log.BlockNumber, log.TxIndex)
+
+		for i, topic := range log.Topics {
+			fmt.Fprintf(writer, "%08d  %x\n", i, topic)
+		}
+
+		fmt.Fprint(writer, hex.Dump(log.Data))
+		fmt.Fprintln(writer)
+	}
+}
+
+type mdLogger struct {
+	out io.Writer
+	cfg *Config
+	env *vm.EVM
+}
+
+// NewMarkdownLogger creates a logger which outputs information in a format adapted
+// for human readability, and is also a valid markdown table
+func NewMarkdownLogger(cfg *Config, writer io.Writer) *mdLogger {
+	l := &mdLogger{out: writer, cfg: cfg}
+	if l.cfg == nil {
+		l.cfg = &Config{}
+	}
+	return l
+}
+
+func (t *mdLogger) CaptureStart(env *vm.EVM, from common.Address, to common.Address, create bool, input []byte, gas uint64, value *big.Int) {
+	t.env = env
+	if !create {
+		fmt.Fprintf(t.out, "From: `%v`\nTo: `%v`\nData: `%#x`\nGas: `%d`\nValue `%v` wei\n",
+			from.String(), to.String(),
+			input, gas, value)
+	} else {
+		fmt.Fprintf(t.out, "From: `%v`\nCreate at: `%v`\nData: `%#x`\nGas: `%d`\nValue `%v` wei\n",
+			from.String(), to.String(),
+			input, gas, value)
+	}
+
+	fmt.Fprintf(t.out, `
+|  Pc   |      Op     | Cost |   Stack   |   RStack  |  Refund |
+|-------|-------------|------|-----------|-----------|---------|
+`)
+}
+
+// CaptureState also tracks SLOAD/SSTORE ops to track storage change.
+func (t *mdLogger) CaptureState(pc uint64, op vm.OpCode, gas, cost uint64, scope *vm.ScopeContext, rData []byte, depth int, err error) {
+	stack := scope.Stack
+	fmt.Fprintf(t.out, "| %4d  | %10v  |  %3d |", pc, op, cost)
+
+	if !t.cfg.DisableStack {
+		// format stack
+		var a []string
+		for _, elem := range stack.Data() {
+			a = append(a, elem.Hex())
+		}
+		b := fmt.Sprintf("[%v]", strings.Join(a, ","))
+		fmt.Fprintf(t.out, "%10v |", b)
+	}
+	fmt.Fprintf(t.out, "%10v |", t.env.StateDB.GetRefund())
+	fmt.Fprintln(t.out, "")
+	if err != nil {
+		fmt.Fprintf(t.out, "Error: %v\n", err)
+	}
+}
+
+func (t *mdLogger) CaptureFault(pc uint64, op vm.OpCode, gas, cost uint64, scope *vm.ScopeContext, depth int, err error) {
+	fmt.Fprintf(t.out, "\nError: at pc=%d, op=%v: %v\n", pc, op, err)
+}
+
+func (t *mdLogger) CaptureEnd(output []byte, gasUsed uint64, tm time.Duration, err error) {
+	fmt.Fprintf(t.out, "\nOutput: `%#x`\nConsumed gas: `%d`\nError: `%v`\n",
+		output, gasUsed, err)
+}
+
+func (t *mdLogger) CaptureEnter(typ vm.OpCode, from common.Address, to common.Address, input []byte, gas uint64, value *big.Int) {
+}
+
+func (t *mdLogger) CaptureExit(output []byte, gasUsed uint64, err error) {}
+
+func (*mdLogger) CaptureTxStart(gasLimit uint64) {}
+
+func (*mdLogger) CaptureTxEnd(restGas uint64) {}
+
+// ExecutionResult groups all structured logs emitted by the EVM
+// while replaying a transaction in debug mode as well as transaction
+// execution status, the amount of gas used and the return value
+type ExecutionResult struct {
+	Gas         uint64         `json:"gas"`
+	Failed      bool           `json:"failed"`
+	ReturnValue string         `json:"returnValue"`
+	StructLogs  []StructLogRes `json:"structLogs"`
+}
+
+// StructLogRes stores a structured log emitted by the EVM while replaying a
+// transaction in debug mode
+type StructLogRes struct {
+	Pc            uint64             `json:"pc"`
+	Op            string             `json:"op"`
+	Gas           uint64             `json:"gas"`
+	GasCost       uint64             `json:"gasCost"`
+	Depth         int                `json:"depth"`
+	Error         string             `json:"error,omitempty"`
+	Stack         *[]string          `json:"stack,omitempty"`
+	Memory        *[]string          `json:"memory,omitempty"`
+	Storage       *map[string]string `json:"storage,omitempty"`
+	RefundCounter uint64             `json:"refund,omitempty"`
+}
+
+// formatLogs formats EVM returned structured logs for json output
+func formatLogs(logs []StructLog) []StructLogRes {
+	formatted := make([]StructLogRes, len(logs))
+	for index, trace := range logs {
+		formatted[index] = StructLogRes{
+			Pc:            trace.Pc,
+			Op:            trace.Op.String(),
+			Gas:           trace.Gas,
+			GasCost:       trace.GasCost,
+			Depth:         trace.Depth,
+			Error:         trace.ErrorString(),
+			RefundCounter: trace.RefundCounter,
+		}
+		if trace.Stack != nil {
+			stack := make([]string, len(trace.Stack))
+			for i, stackValue := range trace.Stack {
+				stack[i] = stackValue.Hex()
+			}
+			formatted[index].Stack = &stack
+		}
+		if trace.Memory != nil {
+			memory := make([]string, 0, (len(trace.Memory)+31)/32)
+			for i := 0; i+32 <= len(trace.Memory); i += 32 {
+				memory = append(memory, fmt.Sprintf("%x", trace.Memory[i:i+32]))
+			}
+			formatted[index].Memory = &memory
+		}
+		if trace.Storage != nil {
+			storage := make(map[string]string)
+			for i, storageValue := range trace.Storage {
+				storage[fmt.Sprintf("%x", i)] = fmt.Sprintf("%x", storageValue)
+			}
+			formatted[index].Storage = &storage
+		}
+	}
+	return formatted
+}

vendor/github.com/ethereum/go-ethereum/eth/tracers/logger/logger_json.go

@@ -0,0 +1,104 @@
+// Copyright 2021 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 logger
+
+import (
+	"encoding/json"
+	"io"
+	"math/big"
+	"time"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/common/math"
+	"github.com/ethereum/go-ethereum/core/vm"
+)
+
+type JSONLogger struct {
+	encoder *json.Encoder
+	cfg     *Config
+	env     *vm.EVM
+}
+
+// NewJSONLogger creates a new EVM tracer that prints execution steps as JSON objects
+// into the provided stream.
+func NewJSONLogger(cfg *Config, writer io.Writer) *JSONLogger {
+	l := &JSONLogger{encoder: json.NewEncoder(writer), cfg: cfg}
+	if l.cfg == nil {
+		l.cfg = &Config{}
+	}
+	return l
+}
+
+func (l *JSONLogger) CaptureStart(env *vm.EVM, from, to common.Address, create bool, input []byte, gas uint64, value *big.Int) {
+	l.env = env
+}
+
+func (l *JSONLogger) CaptureFault(pc uint64, op vm.OpCode, gas uint64, cost uint64, scope *vm.ScopeContext, depth int, err error) {
+	// TODO: Add rData to this interface as well
+	l.CaptureState(pc, op, gas, cost, scope, nil, depth, err)
+}
+
+// CaptureState outputs state information on the logger.
+func (l *JSONLogger) CaptureState(pc uint64, op vm.OpCode, gas, cost uint64, scope *vm.ScopeContext, rData []byte, depth int, err error) {
+	memory := scope.Memory
+	stack := scope.Stack
+
+	log := StructLog{
+		Pc:            pc,
+		Op:            op,
+		Gas:           gas,
+		GasCost:       cost,
+		MemorySize:    memory.Len(),
+		Depth:         depth,
+		RefundCounter: l.env.StateDB.GetRefund(),
+		Err:           err,
+	}
+	if l.cfg.EnableMemory {
+		log.Memory = memory.Data()
+	}
+	if !l.cfg.DisableStack {
+		log.Stack = stack.Data()
+	}
+	if l.cfg.EnableReturnData {
+		log.ReturnData = rData
+	}
+	l.encoder.Encode(log)
+}
+
+// CaptureEnd is triggered at end of execution.
+func (l *JSONLogger) CaptureEnd(output []byte, gasUsed uint64, t time.Duration, err error) {
+	type endLog struct {
+		Output  string              `json:"output"`
+		GasUsed math.HexOrDecimal64 `json:"gasUsed"`
+		Time    time.Duration       `json:"time"`
+		Err     string              `json:"error,omitempty"`
+	}
+	var errMsg string
+	if err != nil {
+		errMsg = err.Error()
+	}
+	l.encoder.Encode(endLog{common.Bytes2Hex(output), math.HexOrDecimal64(gasUsed), t, errMsg})
+}
+
+func (l *JSONLogger) CaptureEnter(typ vm.OpCode, from common.Address, to common.Address, input []byte, gas uint64, value *big.Int) {
+}
+
+func (l *JSONLogger) CaptureExit(output []byte, gasUsed uint64, err error) {}
+
+func (l *JSONLogger) CaptureTxStart(gasLimit uint64) {}
+
+func (l *JSONLogger) CaptureTxEnd(restGas uint64) {}