36 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
		
		
			
		
	
	
			36 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
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								// Copyright 2021 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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								//go:build linux
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								// +build linux
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								package ethash
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								import (
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									"os"
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									"golang.org/x/sys/unix"
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								)
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								// ensureSize expands the file to the given size. This is to prevent runtime
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								// errors later on, if the underlying file expands beyond the disk capacity,
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								// even though it ostensibly is already expanded, but due to being sparse
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								// does not actually occupy the full declared size on disk.
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								func ensureSize(f *os.File, size int64) error {
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									// Docs: https://www.man7.org/linux/man-pages/man2/fallocate.2.html
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									return unix.Fallocate(int(f.Fd()), 0, 0, size)
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								}
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