consensus: extend getWork API with block number (ethereum#18038)

consensus/ethash/api.go

@@ -37,27 +37,28 @@ type API struct {
 //   result[0] - 32 bytes hex encoded current block header pow-hash
 //   result[1] - 32 bytes hex encoded seed hash used for DAG
 //   result[2] - 32 bytes hex encoded boundary condition ("target"), 2^256/difficulty
-func (api *API) GetWork() ([3]string, error) {
+//   result[3] - hex encoded block number
+func (api *API) GetWork() ([4]string, error) {
 	if api.ethash.config.PowMode != ModeNormal && api.ethash.config.PowMode != ModeTest {
-		return [3]string{}, errors.New("not supported")
+		return [4]string{}, errors.New("not supported")
 	}
 
 	var (
-		workCh = make(chan [3]string, 1)
+		workCh = make(chan [4]string, 1)
 		errc   = make(chan error, 1)
 	)
 
 	select {
 	case api.ethash.fetchWorkCh <- &sealWork{errc: errc, res: workCh}:
 	case <-api.ethash.exitCh:
-		return [3]string{}, errEthashStopped
+		return [4]string{}, errEthashStopped
 	}
 
 	select {
 	case work := <-workCh:
 		return work, nil
 	case err := <-errc:
-		return [3]string{}, err
+		return [4]string{}, err
 	}
 }
 

consensus/ethash/ethash.go

@@ -432,7 +432,7 @@ type hashrate struct {
 // sealWork wraps a seal work package for remote sealer.
 type sealWork struct {
 	errc chan error
-	res  chan [3]string
+	res  chan [4]string
 }
 
 // Ethash is a consensus engine based on proof-of-work implementing the ethash

consensus/ethash/ethash_test.go

@@ -107,7 +107,7 @@ func TestRemoteSealer(t *testing.T) {
 	ethash.Seal(nil, block, results, nil)
 
 	var (
-		work [3]string
+		work [4]string
 		err  error
 	)
 	if work, err = api.GetWork(); err != nil || work[0] != sealhash.Hex() {

consensus/ethash/sealer.go

@@ -30,6 +30,7 @@ import (
 	"time"
 
 	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/common/hexutil"
 	"github.com/ethereum/go-ethereum/consensus"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/log"
@@ -193,7 +194,7 @@ func (ethash *Ethash) remote(notify []string, noverify bool) {
 
 		results      chan<- *types.Block
 		currentBlock *types.Block
-		currentWork  [3]string
+		currentWork  [4]string
 
 		notifyTransport = &http.Transport{}
 		notifyClient    = &http.Client{
@@ -234,12 +235,14 @@ func (ethash *Ethash) remote(notify []string, noverify bool) {
 	//   result[0], 32 bytes hex encoded current block header pow-hash
 	//   result[1], 32 bytes hex encoded seed hash used for DAG
 	//   result[2], 32 bytes hex encoded boundary condition ("target"), 2^256/difficulty
+	//   result[3], hex encoded block number
 	makeWork := func(block *types.Block) {
 		hash := ethash.SealHash(block.Header())
 
 		currentWork[0] = hash.Hex()
 		currentWork[1] = common.BytesToHash(SeedHash(block.NumberU64())).Hex()
 		currentWork[2] = common.BytesToHash(new(big.Int).Div(two256, block.Difficulty()).Bytes()).Hex()
+		currentWork[3] = hexutil.EncodeBig(block.Number())
 
 		// Trace the seal work fetched by remote sealer.
 		currentBlock = block