// 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 core import ( "fmt" "math" ) // GasPool tracks the amount of gas available during execution of the transactions // in a block. The zero value is a pool with zero gas available. type GasPool uint64 // AddGas makes gas available for execution. func (gp *GasPool) AddGas(amount uint64) *GasPool { if uint64(*gp) > math.MaxUint64-amount { panic("gas pool pushed above uint64") } *(*uint64)(gp) += amount return gp } // SubGas deducts the given amount from the pool if enough gas is // available and returns an error otherwise. func (gp *GasPool) SubGas(amount uint64) error { if uint64(*gp) < amount { return ErrGasLimitReached } *(*uint64)(gp) -= amount return nil } // Gas returns the amount of gas remaining in the pool. func (gp *GasPool) Gas() uint64 { return uint64(*gp) } func (gp *GasPool) String() string { return fmt.Sprintf("%d", *gp) }