feat: Gasless

cmd/utils/flags.go

@@ -1144,6 +1144,10 @@ func SetEthConfig(ctx *cli.Context, stack *node.Node, cfg *eth.Config) {
 	}
 	if ctx.GlobalIsSet(GasPriceFlag.Name) {
 		cfg.GasPrice = GlobalBig(ctx, GasPriceFlag.Name)
+		if len(cfg.GasPrice.Bits()) == 0 { //IsUint64() && cfg.GasPrice.Uint64() == 0 {
+			common.Gasless = true
+			log.Info("Gasless enabled. You can run transactions with zero gas fee.")
+		}
 	}
 	if ctx.GlobalIsSet(VMEnableDebugFlag.Name) {
 		// TODO(fjl): force-enable this in --dev mode

common/gas.go

@@ -7,7 +7,12 @@ import (
 var MinGasPrice50x = big.NewInt(12500000000)
 var GasPrice50x = big.NewInt(12500000000)
 
+var Gasless = false
+
 func GetGasFee(blockNumber, gas uint64) *big.Int {
+	if Gasless {
+		return big.NewInt(0)
+	}
 	fee := new(big.Int).SetUint64(gas)
 	if blockNumber >= uint64(10) { //temp fix trc21issuer test fail
 		fee = fee.Mul(fee, GasPrice50x)
@@ -16,15 +21,21 @@ func GetGasFee(blockNumber, gas uint64) *big.Int {
 }
 
 func GetGasPrice(number *big.Int) *big.Int {
+	if Gasless {
+		return big.NewInt(0)
+	}
 	if number == nil {
 		return new(big.Int).Set(TRC21GasPrice)
 	}
 	return new(big.Int).Set(GasPrice50x)
 }
 
 func GetMinGasPrice(number *big.Int) *big.Int {
+	if Gasless {
+		return big.NewInt(0)
+	}
 	if number == nil {
 		return new(big.Int).Set(MinGasPrice)
 	}
 	return new(big.Int).Set(MinGasPrice50x)
-}
+}

core/tx_pool.go

@@ -664,7 +664,9 @@ func (pool *TxPool) validateTx(tx *types.Transaction, local bool) error {
 
 		// Check zero gas price.
 		if tx.GasPrice().Cmp(new(big.Int).SetInt64(0)) == 0 {
-			return ErrZeroGasPrice
+			if !common.Gasless {
+				return ErrZeroGasPrice
+			}
 		}
 
 		// under min gas price

eth/gasprice/gasprice.go

@@ -75,6 +75,9 @@ func NewOracle(backend ethapi.Backend, params Config) *Oracle {
 
 // SuggestPrice returns the recommended gas price.
 func (gpo *Oracle) SuggestPrice(ctx context.Context) (*big.Int, error) {
+	if common.Gasless {
+		return big.NewInt(0), nil
+	}
 	gpo.cacheLock.RLock()
 	lastHead := gpo.lastHead
 	lastPrice := gpo.lastPrice