55 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
			
		
		
	
	
			55 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
// Copyright 2015 The go-ethereum Authors
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// This file is part of the go-ethereum library.
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//
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// The go-ethereum library is free software: you can redistribute it and/or modify
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// it under the terms of the GNU Lesser General Public License as published by
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// the Free Software Foundation, either version 3 of the License, or
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// (at your option) any later version.
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//
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// The go-ethereum library is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU Lesser General Public License for more details.
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//
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// You should have received a copy of the GNU Lesser General Public License
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// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
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package core
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import (
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	"fmt"
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	"math"
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)
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// GasPool tracks the amount of gas available during execution of the transactions
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// in a block. The zero value is a pool with zero gas available.
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type GasPool uint64
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// AddGas makes gas available for execution.
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func (gp *GasPool) AddGas(amount uint64) *GasPool {
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	if uint64(*gp) > math.MaxUint64-amount {
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		panic("gas pool pushed above uint64")
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	}
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	*(*uint64)(gp) += amount
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	return gp
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}
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// SubGas deducts the given amount from the pool if enough gas is
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// available and returns an error otherwise.
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func (gp *GasPool) SubGas(amount uint64) error {
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	if uint64(*gp) < amount {
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		return ErrGasLimitReached
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	}
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	*(*uint64)(gp) -= amount
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	return nil
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}
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// Gas returns the amount of gas remaining in the pool.
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func (gp *GasPool) Gas() uint64 {
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	return uint64(*gp)
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}
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func (gp *GasPool) String() string {
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	return fmt.Sprintf("%d", *gp)
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}
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