67 lines
		
	
	
		
			1.5 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
		
		
			
		
	
	
			67 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 | ||
|  | } | ||
|  | 
 | ||
|  | func (bv *BitVector) Length() int { | ||
|  | 	return bv.len | ||
|  | } |