63 lines
		
	
	
		
			1.5 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
			
		
		
	
	
			63 lines
		
	
	
		
			1.5 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
| // Copyright 2018 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 bitvector
 | |
| 
 | |
| import (
 | |
| 	"errors"
 | |
| )
 | |
| 
 | |
| var errInvalidLength = errors.New("invalid length")
 | |
| 
 | |
| type BitVector struct {
 | |
| 	len int
 | |
| 	b   []byte
 | |
| }
 | |
| 
 | |
| func New(l int) (bv *BitVector, err error) {
 | |
| 	return NewFromBytes(make([]byte, l/8+1), l)
 | |
| }
 | |
| 
 | |
| func NewFromBytes(b []byte, l int) (bv *BitVector, err error) {
 | |
| 	if l <= 0 {
 | |
| 		return nil, errInvalidLength
 | |
| 	}
 | |
| 	if len(b)*8 < l {
 | |
| 		return nil, errInvalidLength
 | |
| 	}
 | |
| 	return &BitVector{
 | |
| 		len: l,
 | |
| 		b:   b,
 | |
| 	}, nil
 | |
| }
 | |
| 
 | |
| func (bv *BitVector) Get(i int) bool {
 | |
| 	bi := i / 8
 | |
| 	return bv.b[bi]&(0x1<<uint(i%8)) != 0
 | |
| }
 | |
| 
 | |
| func (bv *BitVector) Set(i int, v bool) {
 | |
| 	bi := i / 8
 | |
| 	cv := bv.Get(i)
 | |
| 	if cv != v {
 | |
| 		bv.b[bi] ^= 0x1 << uint8(i%8)
 | |
| 	}
 | |
| }
 | |
| 
 | |
| func (bv *BitVector) Bytes() []byte {
 | |
| 	return bv.b
 | |
| }
 |