github.com/jonkofee/go-ethereum@v1.11.1/eth/api.go (about)

     1  // Copyright 2015 The go-ethereum Authors
     2  // This file is part of the go-ethereum library.
     3  //
     4  // The go-ethereum library is free software: you can redistribute it and/or modify
     5  // it under the terms of the GNU Lesser General Public License as published by
     6  // the Free Software Foundation, either version 3 of the License, or
     7  // (at your option) any later version.
     8  //
     9  // The go-ethereum library is distributed in the hope that it will be useful,
    10  // but WITHOUT ANY WARRANTY; without even the implied warranty of
    11  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    12  // GNU Lesser General Public License for more details.
    13  //
    14  // You should have received a copy of the GNU Lesser General Public License
    15  // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
    16  
    17  package eth
    18  
    19  import (
    20  	"compress/gzip"
    21  	"context"
    22  	"errors"
    23  	"fmt"
    24  	"io"
    25  	"math/big"
    26  	"os"
    27  	"runtime"
    28  	"strings"
    29  	"time"
    30  
    31  	"github.com/jonkofee/go-ethereum/common"
    32  	"github.com/jonkofee/go-ethereum/common/hexutil"
    33  	"github.com/jonkofee/go-ethereum/core"
    34  	"github.com/jonkofee/go-ethereum/core/rawdb"
    35  	"github.com/jonkofee/go-ethereum/core/state"
    36  	"github.com/jonkofee/go-ethereum/core/types"
    37  	"github.com/jonkofee/go-ethereum/internal/ethapi"
    38  	"github.com/jonkofee/go-ethereum/log"
    39  	"github.com/jonkofee/go-ethereum/rlp"
    40  	"github.com/jonkofee/go-ethereum/rpc"
    41  	"github.com/jonkofee/go-ethereum/trie"
    42  )
    43  
    44  // EthereumAPI provides an API to access Ethereum full node-related information.
    45  type EthereumAPI struct {
    46  	e *Ethereum
    47  }
    48  
    49  // NewEthereumAPI creates a new Ethereum protocol API for full nodes.
    50  func NewEthereumAPI(e *Ethereum) *EthereumAPI {
    51  	return &EthereumAPI{e}
    52  }
    53  
    54  // Etherbase is the address that mining rewards will be send to.
    55  func (api *EthereumAPI) Etherbase() (common.Address, error) {
    56  	return api.e.Etherbase()
    57  }
    58  
    59  // Coinbase is the address that mining rewards will be send to (alias for Etherbase).
    60  func (api *EthereumAPI) Coinbase() (common.Address, error) {
    61  	return api.Etherbase()
    62  }
    63  
    64  // Hashrate returns the POW hashrate.
    65  func (api *EthereumAPI) Hashrate() hexutil.Uint64 {
    66  	return hexutil.Uint64(api.e.Miner().Hashrate())
    67  }
    68  
    69  // Mining returns an indication if this node is currently mining.
    70  func (api *EthereumAPI) Mining() bool {
    71  	return api.e.IsMining()
    72  }
    73  
    74  // MinerAPI provides an API to control the miner.
    75  type MinerAPI struct {
    76  	e *Ethereum
    77  }
    78  
    79  // NewMinerAPI create a new MinerAPI instance.
    80  func NewMinerAPI(e *Ethereum) *MinerAPI {
    81  	return &MinerAPI{e}
    82  }
    83  
    84  // Start starts the miner with the given number of threads. If threads is nil,
    85  // the number of workers started is equal to the number of logical CPUs that are
    86  // usable by this process. If mining is already running, this method adjust the
    87  // number of threads allowed to use and updates the minimum price required by the
    88  // transaction pool.
    89  func (api *MinerAPI) Start(threads *int) error {
    90  	if threads == nil {
    91  		return api.e.StartMining(runtime.NumCPU())
    92  	}
    93  	return api.e.StartMining(*threads)
    94  }
    95  
    96  // Stop terminates the miner, both at the consensus engine level as well as at
    97  // the block creation level.
    98  func (api *MinerAPI) Stop() {
    99  	api.e.StopMining()
   100  }
   101  
   102  // SetExtra sets the extra data string that is included when this miner mines a block.
   103  func (api *MinerAPI) SetExtra(extra string) (bool, error) {
   104  	if err := api.e.Miner().SetExtra([]byte(extra)); err != nil {
   105  		return false, err
   106  	}
   107  	return true, nil
   108  }
   109  
   110  // SetGasPrice sets the minimum accepted gas price for the miner.
   111  func (api *MinerAPI) SetGasPrice(gasPrice hexutil.Big) bool {
   112  	api.e.lock.Lock()
   113  	api.e.gasPrice = (*big.Int)(&gasPrice)
   114  	api.e.lock.Unlock()
   115  
   116  	api.e.txPool.SetGasPrice((*big.Int)(&gasPrice))
   117  	return true
   118  }
   119  
   120  // SetGasLimit sets the gaslimit to target towards during mining.
   121  func (api *MinerAPI) SetGasLimit(gasLimit hexutil.Uint64) bool {
   122  	api.e.Miner().SetGasCeil(uint64(gasLimit))
   123  	return true
   124  }
   125  
   126  // SetEtherbase sets the etherbase of the miner.
   127  func (api *MinerAPI) SetEtherbase(etherbase common.Address) bool {
   128  	api.e.SetEtherbase(etherbase)
   129  	return true
   130  }
   131  
   132  // SetRecommitInterval updates the interval for miner sealing work recommitting.
   133  func (api *MinerAPI) SetRecommitInterval(interval int) {
   134  	api.e.Miner().SetRecommitInterval(time.Duration(interval) * time.Millisecond)
   135  }
   136  
   137  // AdminAPI is the collection of Ethereum full node related APIs for node
   138  // administration.
   139  type AdminAPI struct {
   140  	eth *Ethereum
   141  }
   142  
   143  // NewAdminAPI creates a new instance of AdminAPI.
   144  func NewAdminAPI(eth *Ethereum) *AdminAPI {
   145  	return &AdminAPI{eth: eth}
   146  }
   147  
   148  // ExportChain exports the current blockchain into a local file,
   149  // or a range of blocks if first and last are non-nil.
   150  func (api *AdminAPI) ExportChain(file string, first *uint64, last *uint64) (bool, error) {
   151  	if first == nil && last != nil {
   152  		return false, errors.New("last cannot be specified without first")
   153  	}
   154  	if first != nil && last == nil {
   155  		head := api.eth.BlockChain().CurrentHeader().Number.Uint64()
   156  		last = &head
   157  	}
   158  	if _, err := os.Stat(file); err == nil {
   159  		// File already exists. Allowing overwrite could be a DoS vector,
   160  		// since the 'file' may point to arbitrary paths on the drive.
   161  		return false, errors.New("location would overwrite an existing file")
   162  	}
   163  	// Make sure we can create the file to export into
   164  	out, err := os.OpenFile(file, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, os.ModePerm)
   165  	if err != nil {
   166  		return false, err
   167  	}
   168  	defer out.Close()
   169  
   170  	var writer io.Writer = out
   171  	if strings.HasSuffix(file, ".gz") {
   172  		writer = gzip.NewWriter(writer)
   173  		defer writer.(*gzip.Writer).Close()
   174  	}
   175  
   176  	// Export the blockchain
   177  	if first != nil {
   178  		if err := api.eth.BlockChain().ExportN(writer, *first, *last); err != nil {
   179  			return false, err
   180  		}
   181  	} else if err := api.eth.BlockChain().Export(writer); err != nil {
   182  		return false, err
   183  	}
   184  	return true, nil
   185  }
   186  
   187  func hasAllBlocks(chain *core.BlockChain, bs []*types.Block) bool {
   188  	for _, b := range bs {
   189  		if !chain.HasBlock(b.Hash(), b.NumberU64()) {
   190  			return false
   191  		}
   192  	}
   193  
   194  	return true
   195  }
   196  
   197  // ImportChain imports a blockchain from a local file.
   198  func (api *AdminAPI) ImportChain(file string) (bool, error) {
   199  	// Make sure the can access the file to import
   200  	in, err := os.Open(file)
   201  	if err != nil {
   202  		return false, err
   203  	}
   204  	defer in.Close()
   205  
   206  	var reader io.Reader = in
   207  	if strings.HasSuffix(file, ".gz") {
   208  		if reader, err = gzip.NewReader(reader); err != nil {
   209  			return false, err
   210  		}
   211  	}
   212  
   213  	// Run actual the import in pre-configured batches
   214  	stream := rlp.NewStream(reader, 0)
   215  
   216  	blocks, index := make([]*types.Block, 0, 2500), 0
   217  	for batch := 0; ; batch++ {
   218  		// Load a batch of blocks from the input file
   219  		for len(blocks) < cap(blocks) {
   220  			block := new(types.Block)
   221  			if err := stream.Decode(block); err == io.EOF {
   222  				break
   223  			} else if err != nil {
   224  				return false, fmt.Errorf("block %d: failed to parse: %v", index, err)
   225  			}
   226  			blocks = append(blocks, block)
   227  			index++
   228  		}
   229  		if len(blocks) == 0 {
   230  			break
   231  		}
   232  
   233  		if hasAllBlocks(api.eth.BlockChain(), blocks) {
   234  			blocks = blocks[:0]
   235  			continue
   236  		}
   237  		// Import the batch and reset the buffer
   238  		if _, err := api.eth.BlockChain().InsertChain(blocks); err != nil {
   239  			return false, fmt.Errorf("batch %d: failed to insert: %v", batch, err)
   240  		}
   241  		blocks = blocks[:0]
   242  	}
   243  	return true, nil
   244  }
   245  
   246  // DebugAPI is the collection of Ethereum full node APIs for debugging the
   247  // protocol.
   248  type DebugAPI struct {
   249  	eth *Ethereum
   250  }
   251  
   252  // NewDebugAPI creates a new DebugAPI instance.
   253  func NewDebugAPI(eth *Ethereum) *DebugAPI {
   254  	return &DebugAPI{eth: eth}
   255  }
   256  
   257  // DumpBlock retrieves the entire state of the database at a given block.
   258  func (api *DebugAPI) DumpBlock(blockNr rpc.BlockNumber) (state.Dump, error) {
   259  	opts := &state.DumpConfig{
   260  		OnlyWithAddresses: true,
   261  		Max:               AccountRangeMaxResults, // Sanity limit over RPC
   262  	}
   263  	// arbitrum: in case of ArbEthereum, miner in not available here
   264  	// use current block instead of pending
   265  	if blockNr == rpc.PendingBlockNumber && api.eth.miner == nil {
   266  		blockNr = rpc.LatestBlockNumber
   267  	}
   268  	if blockNr == rpc.PendingBlockNumber {
   269  		// If we're dumping the pending state, we need to request
   270  		// both the pending block as well as the pending state from
   271  		// the miner and operate on those
   272  		_, stateDb := api.eth.miner.Pending()
   273  		return stateDb.RawDump(opts), nil
   274  	}
   275  	var block *types.Block
   276  	if blockNr == rpc.LatestBlockNumber {
   277  		block = api.eth.blockchain.CurrentBlock()
   278  	} else if blockNr == rpc.FinalizedBlockNumber {
   279  		block = api.eth.blockchain.CurrentFinalizedBlock()
   280  	} else if blockNr == rpc.SafeBlockNumber {
   281  		block = api.eth.blockchain.CurrentSafeBlock()
   282  	} else {
   283  		block = api.eth.blockchain.GetBlockByNumber(uint64(blockNr))
   284  	}
   285  	if block == nil {
   286  		return state.Dump{}, fmt.Errorf("block #%d not found", blockNr)
   287  	}
   288  	stateDb, err := api.eth.BlockChain().StateAt(block.Root())
   289  	if err != nil {
   290  		return state.Dump{}, err
   291  	}
   292  	return stateDb.RawDump(opts), nil
   293  }
   294  
   295  // Preimage is a debug API function that returns the preimage for a sha3 hash, if known.
   296  func (api *DebugAPI) Preimage(ctx context.Context, hash common.Hash) (hexutil.Bytes, error) {
   297  	if preimage := rawdb.ReadPreimage(api.eth.ChainDb(), hash); preimage != nil {
   298  		return preimage, nil
   299  	}
   300  	return nil, errors.New("unknown preimage")
   301  }
   302  
   303  // BadBlockArgs represents the entries in the list returned when bad blocks are queried.
   304  type BadBlockArgs struct {
   305  	Hash  common.Hash            `json:"hash"`
   306  	Block map[string]interface{} `json:"block"`
   307  	RLP   string                 `json:"rlp"`
   308  }
   309  
   310  // GetBadBlocks returns a list of the last 'bad blocks' that the client has seen on the network
   311  // and returns them as a JSON list of block hashes.
   312  func (api *DebugAPI) GetBadBlocks(ctx context.Context) ([]*BadBlockArgs, error) {
   313  	var (
   314  		err     error
   315  		blocks  = rawdb.ReadAllBadBlocks(api.eth.chainDb)
   316  		results = make([]*BadBlockArgs, 0, len(blocks))
   317  	)
   318  	for _, block := range blocks {
   319  		var (
   320  			blockRlp  string
   321  			blockJSON map[string]interface{}
   322  		)
   323  		if rlpBytes, err := rlp.EncodeToBytes(block); err != nil {
   324  			blockRlp = err.Error() // Hacky, but hey, it works
   325  		} else {
   326  			blockRlp = fmt.Sprintf("%#x", rlpBytes)
   327  		}
   328  		if blockJSON, err = ethapi.RPCMarshalBlock(block, true, true, api.eth.blockchain.Config()); err != nil {
   329  			blockJSON = map[string]interface{}{"error": err.Error()}
   330  		}
   331  		results = append(results, &BadBlockArgs{
   332  			Hash:  block.Hash(),
   333  			RLP:   blockRlp,
   334  			Block: blockJSON,
   335  		})
   336  	}
   337  	return results, nil
   338  }
   339  
   340  // AccountRangeMaxResults is the maximum number of results to be returned per call
   341  const AccountRangeMaxResults = 256
   342  
   343  // AccountRange enumerates all accounts in the given block and start point in paging request
   344  func (api *DebugAPI) AccountRange(blockNrOrHash rpc.BlockNumberOrHash, start hexutil.Bytes, maxResults int, nocode, nostorage, incompletes bool) (state.IteratorDump, error) {
   345  	var stateDb *state.StateDB
   346  	var err error
   347  
   348  	if number, ok := blockNrOrHash.Number(); ok {
   349  		// arbitrum: in case of ArbEthereum, miner in not available here
   350  		// use current block instead of pending
   351  		if number == rpc.PendingBlockNumber && api.eth.miner == nil {
   352  			number = rpc.LatestBlockNumber
   353  		}
   354  		if number == rpc.PendingBlockNumber {
   355  			// If we're dumping the pending state, we need to request
   356  			// both the pending block as well as the pending state from
   357  			// the miner and operate on those
   358  			_, stateDb = api.eth.miner.Pending()
   359  		} else {
   360  			var block *types.Block
   361  			if number == rpc.LatestBlockNumber {
   362  				block = api.eth.blockchain.CurrentBlock()
   363  			} else if number == rpc.FinalizedBlockNumber {
   364  				block = api.eth.blockchain.CurrentFinalizedBlock()
   365  			} else if number == rpc.SafeBlockNumber {
   366  				block = api.eth.blockchain.CurrentSafeBlock()
   367  			} else {
   368  				block = api.eth.blockchain.GetBlockByNumber(uint64(number))
   369  			}
   370  			if block == nil {
   371  				return state.IteratorDump{}, fmt.Errorf("block #%d not found", number)
   372  			}
   373  			stateDb, err = api.eth.BlockChain().StateAt(block.Root())
   374  			if err != nil {
   375  				return state.IteratorDump{}, err
   376  			}
   377  		}
   378  	} else if hash, ok := blockNrOrHash.Hash(); ok {
   379  		block := api.eth.blockchain.GetBlockByHash(hash)
   380  		if block == nil {
   381  			return state.IteratorDump{}, fmt.Errorf("block %s not found", hash.Hex())
   382  		}
   383  		stateDb, err = api.eth.BlockChain().StateAt(block.Root())
   384  		if err != nil {
   385  			return state.IteratorDump{}, err
   386  		}
   387  	} else {
   388  		return state.IteratorDump{}, errors.New("either block number or block hash must be specified")
   389  	}
   390  
   391  	opts := &state.DumpConfig{
   392  		SkipCode:          nocode,
   393  		SkipStorage:       nostorage,
   394  		OnlyWithAddresses: !incompletes,
   395  		Start:             start,
   396  		Max:               uint64(maxResults),
   397  	}
   398  	if maxResults > AccountRangeMaxResults || maxResults <= 0 {
   399  		opts.Max = AccountRangeMaxResults
   400  	}
   401  	return stateDb.IteratorDump(opts), nil
   402  }
   403  
   404  // StorageRangeResult is the result of a debug_storageRangeAt API call.
   405  type StorageRangeResult struct {
   406  	Storage storageMap   `json:"storage"`
   407  	NextKey *common.Hash `json:"nextKey"` // nil if Storage includes the last key in the trie.
   408  }
   409  
   410  type storageMap map[common.Hash]storageEntry
   411  
   412  type storageEntry struct {
   413  	Key   *common.Hash `json:"key"`
   414  	Value common.Hash  `json:"value"`
   415  }
   416  
   417  // StorageRangeAt returns the storage at the given block height and transaction index.
   418  func (api *DebugAPI) StorageRangeAt(blockHash common.Hash, txIndex int, contractAddress common.Address, keyStart hexutil.Bytes, maxResult int) (StorageRangeResult, error) {
   419  	// Retrieve the block
   420  	block := api.eth.blockchain.GetBlockByHash(blockHash)
   421  	if block == nil {
   422  		return StorageRangeResult{}, fmt.Errorf("block %#x not found", blockHash)
   423  	}
   424  	_, _, statedb, err := api.eth.stateAtTransaction(block, txIndex, 0)
   425  	if err != nil {
   426  		return StorageRangeResult{}, err
   427  	}
   428  	st := statedb.StorageTrie(contractAddress)
   429  	if st == nil {
   430  		return StorageRangeResult{}, fmt.Errorf("account %x doesn't exist", contractAddress)
   431  	}
   432  	return storageRangeAt(st, keyStart, maxResult)
   433  }
   434  
   435  func storageRangeAt(st state.Trie, start []byte, maxResult int) (StorageRangeResult, error) {
   436  	it := trie.NewIterator(st.NodeIterator(start))
   437  	result := StorageRangeResult{Storage: storageMap{}}
   438  	for i := 0; i < maxResult && it.Next(); i++ {
   439  		_, content, _, err := rlp.Split(it.Value)
   440  		if err != nil {
   441  			return StorageRangeResult{}, err
   442  		}
   443  		e := storageEntry{Value: common.BytesToHash(content)}
   444  		if preimage := st.GetKey(it.Key); preimage != nil {
   445  			preimage := common.BytesToHash(preimage)
   446  			e.Key = &preimage
   447  		}
   448  		result.Storage[common.BytesToHash(it.Key)] = e
   449  	}
   450  	// Add the 'next key' so clients can continue downloading.
   451  	if it.Next() {
   452  		next := common.BytesToHash(it.Key)
   453  		result.NextKey = &next
   454  	}
   455  	return result, nil
   456  }
   457  
   458  // GetModifiedAccountsByNumber returns all accounts that have changed between the
   459  // two blocks specified. A change is defined as a difference in nonce, balance,
   460  // code hash, or storage hash.
   461  //
   462  // With one parameter, returns the list of accounts modified in the specified block.
   463  func (api *DebugAPI) GetModifiedAccountsByNumber(startNum uint64, endNum *uint64) ([]common.Address, error) {
   464  	var startBlock, endBlock *types.Block
   465  
   466  	startBlock = api.eth.blockchain.GetBlockByNumber(startNum)
   467  	if startBlock == nil {
   468  		return nil, fmt.Errorf("start block %x not found", startNum)
   469  	}
   470  
   471  	if endNum == nil {
   472  		endBlock = startBlock
   473  		startBlock = api.eth.blockchain.GetBlockByHash(startBlock.ParentHash())
   474  		if startBlock == nil {
   475  			return nil, fmt.Errorf("block %x has no parent", endBlock.Number())
   476  		}
   477  	} else {
   478  		endBlock = api.eth.blockchain.GetBlockByNumber(*endNum)
   479  		if endBlock == nil {
   480  			return nil, fmt.Errorf("end block %d not found", *endNum)
   481  		}
   482  	}
   483  	return api.getModifiedAccounts(startBlock, endBlock)
   484  }
   485  
   486  // GetModifiedAccountsByHash returns all accounts that have changed between the
   487  // two blocks specified. A change is defined as a difference in nonce, balance,
   488  // code hash, or storage hash.
   489  //
   490  // With one parameter, returns the list of accounts modified in the specified block.
   491  func (api *DebugAPI) GetModifiedAccountsByHash(startHash common.Hash, endHash *common.Hash) ([]common.Address, error) {
   492  	var startBlock, endBlock *types.Block
   493  	startBlock = api.eth.blockchain.GetBlockByHash(startHash)
   494  	if startBlock == nil {
   495  		return nil, fmt.Errorf("start block %x not found", startHash)
   496  	}
   497  
   498  	if endHash == nil {
   499  		endBlock = startBlock
   500  		startBlock = api.eth.blockchain.GetBlockByHash(startBlock.ParentHash())
   501  		if startBlock == nil {
   502  			return nil, fmt.Errorf("block %x has no parent", endBlock.Number())
   503  		}
   504  	} else {
   505  		endBlock = api.eth.blockchain.GetBlockByHash(*endHash)
   506  		if endBlock == nil {
   507  			return nil, fmt.Errorf("end block %x not found", *endHash)
   508  		}
   509  	}
   510  	return api.getModifiedAccounts(startBlock, endBlock)
   511  }
   512  
   513  func (api *DebugAPI) getModifiedAccounts(startBlock, endBlock *types.Block) ([]common.Address, error) {
   514  	if startBlock.Number().Uint64() >= endBlock.Number().Uint64() {
   515  		return nil, fmt.Errorf("start block height (%d) must be less than end block height (%d)", startBlock.Number().Uint64(), endBlock.Number().Uint64())
   516  	}
   517  	triedb := api.eth.BlockChain().StateCache().TrieDB()
   518  
   519  	oldTrie, err := trie.NewStateTrie(common.Hash{}, startBlock.Root(), triedb)
   520  	if err != nil {
   521  		return nil, err
   522  	}
   523  	newTrie, err := trie.NewStateTrie(common.Hash{}, endBlock.Root(), triedb)
   524  	if err != nil {
   525  		return nil, err
   526  	}
   527  	diff, _ := trie.NewDifferenceIterator(oldTrie.NodeIterator([]byte{}), newTrie.NodeIterator([]byte{}))
   528  	iter := trie.NewIterator(diff)
   529  
   530  	var dirty []common.Address
   531  	for iter.Next() {
   532  		key := newTrie.GetKey(iter.Key)
   533  		if key == nil {
   534  			return nil, fmt.Errorf("no preimage found for hash %x", iter.Key)
   535  		}
   536  		dirty = append(dirty, common.BytesToAddress(key))
   537  	}
   538  	return dirty, nil
   539  }
   540  
   541  // GetAccessibleState returns the first number where the node has accessible
   542  // state on disk. Note this being the post-state of that block and the pre-state
   543  // of the next block.
   544  // The (from, to) parameters are the sequence of blocks to search, which can go
   545  // either forwards or backwards
   546  func (api *DebugAPI) GetAccessibleState(from, to rpc.BlockNumber) (uint64, error) {
   547  	db := api.eth.ChainDb()
   548  	var pivot uint64
   549  	if p := rawdb.ReadLastPivotNumber(db); p != nil {
   550  		pivot = *p
   551  		log.Info("Found fast-sync pivot marker", "number", pivot)
   552  	}
   553  	var resolveNum = func(num rpc.BlockNumber) (uint64, error) {
   554  		// We don't have state for pending (-2), so treat it as latest
   555  		if num.Int64() < 0 {
   556  			block := api.eth.blockchain.CurrentBlock()
   557  			if block == nil {
   558  				return 0, fmt.Errorf("current block missing")
   559  			}
   560  			return block.NumberU64(), nil
   561  		}
   562  		return uint64(num.Int64()), nil
   563  	}
   564  	var (
   565  		start   uint64
   566  		end     uint64
   567  		delta   = int64(1)
   568  		lastLog time.Time
   569  		err     error
   570  	)
   571  	if start, err = resolveNum(from); err != nil {
   572  		return 0, err
   573  	}
   574  	if end, err = resolveNum(to); err != nil {
   575  		return 0, err
   576  	}
   577  	if start == end {
   578  		return 0, fmt.Errorf("from and to needs to be different")
   579  	}
   580  	if start > end {
   581  		delta = -1
   582  	}
   583  	for i := int64(start); i != int64(end); i += delta {
   584  		if time.Since(lastLog) > 8*time.Second {
   585  			log.Info("Finding roots", "from", start, "to", end, "at", i)
   586  			lastLog = time.Now()
   587  		}
   588  		if i < int64(pivot) {
   589  			continue
   590  		}
   591  		h := api.eth.BlockChain().GetHeaderByNumber(uint64(i))
   592  		if h == nil {
   593  			return 0, fmt.Errorf("missing header %d", i)
   594  		}
   595  		if ok, _ := api.eth.ChainDb().Has(h.Root[:]); ok {
   596  			return uint64(i), nil
   597  		}
   598  	}
   599  	return 0, errors.New("no state found")
   600  }