Merge pull request #10543 from containers/dependabot/go_modules/github.com/opencontainers/selinux-1.8.2

Bump github.com/opencontainers/selinux from 1.8.1 to 1.8.2

1 files changed, 952 insertions, 0 deletions

diff --git a/vendor/github.com/bits-and-blooms/bitset/bitset.go b/vendor/github.com/bits-and-blooms/bitset/bitset.go
new file mode 100644
index 000000000..d688806a5
--- /dev/null
+++ b/vendor/github.com/bits-and-blooms/bitset/bitset.go
@@ -0,0 +1,952 @@
+/*
+Package bitset implements bitsets, a mapping
+between non-negative integers and boolean values. It should be more
+efficient than map[uint] bool.
+
+It provides methods for setting, clearing, flipping, and testing
+individual integers.
+
+But it also provides set intersection, union, difference,
+complement, and symmetric operations, as well as tests to
+check whether any, all, or no bits are set, and querying a
+bitset's current length and number of positive bits.
+
+BitSets are expanded to the size of the largest set bit; the
+memory allocation is approximately Max bits, where Max is
+the largest set bit. BitSets are never shrunk. On creation,
+a hint can be given for the number of bits that will be used.
+
+Many of the methods, including Set,Clear, and Flip, return
+a BitSet pointer, which allows for chaining.
+
+Example use:
+
+	import "bitset"
+	var b BitSet
+	b.Set(10).Set(11)
+	if b.Test(1000) {
+		b.Clear(1000)
+	}
+	if B.Intersection(bitset.New(100).Set(10)).Count() > 1 {
+		fmt.Println("Intersection works.")
+	}
+
+As an alternative to BitSets, one should check out the 'big' package,
+which provides a (less set-theoretical) view of bitsets.
+
+*/
+package bitset
+
+import (
+	"bufio"
+	"bytes"
+	"encoding/base64"
+	"encoding/binary"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"strconv"
+)
+
+// the wordSize of a bit set
+const wordSize = uint(64)
+
+// log2WordSize is lg(wordSize)
+const log2WordSize = uint(6)
+
+// allBits has every bit set
+const allBits uint64 = 0xffffffffffffffff
+
+// default binary BigEndian
+var binaryOrder binary.ByteOrder = binary.BigEndian
+
+// default json encoding base64.URLEncoding
+var base64Encoding = base64.URLEncoding
+
+// Base64StdEncoding Marshal/Unmarshal BitSet with base64.StdEncoding(Default: base64.URLEncoding)
+func Base64StdEncoding() { base64Encoding = base64.StdEncoding }
+
+// LittleEndian Marshal/Unmarshal Binary as Little Endian(Default: binary.BigEndian)
+func LittleEndian() { binaryOrder = binary.LittleEndian }
+
+// A BitSet is a set of bits. The zero value of a BitSet is an empty set of length 0.
+type BitSet struct {
+	length uint
+	set    []uint64
+}
+
+// Error is used to distinguish errors (panics) generated in this package.
+type Error string
+
+// safeSet will fixup b.set to be non-nil and return the field value
+func (b *BitSet) safeSet() []uint64 {
+	if b.set == nil {
+		b.set = make([]uint64, wordsNeeded(0))
+	}
+	return b.set
+}
+
+// From is a constructor used to create a BitSet from an array of integers
+func From(buf []uint64) *BitSet {
+	return &BitSet{uint(len(buf)) * 64, buf}
+}
+
+// Bytes returns the bitset as array of integers
+func (b *BitSet) Bytes() []uint64 {
+	return b.set
+}
+
+// wordsNeeded calculates the number of words needed for i bits
+func wordsNeeded(i uint) int {
+	if i > (Cap() - wordSize + 1) {
+		return int(Cap() >> log2WordSize)
+	}
+	return int((i + (wordSize - 1)) >> log2WordSize)
+}
+
+// New creates a new BitSet with a hint that length bits will be required
+func New(length uint) (bset *BitSet) {
+	defer func() {
+		if r := recover(); r != nil {
+			bset = &BitSet{
+				0,
+				make([]uint64, 0),
+			}
+		}
+	}()
+
+	bset = &BitSet{
+		length,
+		make([]uint64, wordsNeeded(length)),
+	}
+
+	return bset
+}
+
+// Cap returns the total possible capacity, or number of bits
+func Cap() uint {
+	return ^uint(0)
+}
+
+// Len returns the number of bits in the BitSet.
+// Note the difference to method Count, see example.
+func (b *BitSet) Len() uint {
+	return b.length
+}
+
+// extendSetMaybe adds additional words to incorporate new bits if needed
+func (b *BitSet) extendSetMaybe(i uint) {
+	if i >= b.length { // if we need more bits, make 'em
+		if i >= Cap() {
+			panic("You are exceeding the capacity")
+		}
+		nsize := wordsNeeded(i + 1)
+		if b.set == nil {
+			b.set = make([]uint64, nsize)
+		} else if cap(b.set) >= nsize {
+			b.set = b.set[:nsize] // fast resize
+		} else if len(b.set) < nsize {
+			newset := make([]uint64, nsize, 2*nsize) // increase capacity 2x
+			copy(newset, b.set)
+			b.set = newset
+		}
+		b.length = i + 1
+	}
+}
+
+// Test whether bit i is set.
+func (b *BitSet) Test(i uint) bool {
+	if i >= b.length {
+		return false
+	}
+	return b.set[i>>log2WordSize]&(1<<(i&(wordSize-1))) != 0
+}
+
+// Set bit i to 1, the capacity of the bitset is automatically
+// increased accordingly.
+// If i>= Cap(), this function will panic.
+// Warning: using a very large value for 'i'
+// may lead to a memory shortage and a panic: the caller is responsible
+// for providing sensible parameters in line with their memory capacity.
+func (b *BitSet) Set(i uint) *BitSet {
+	b.extendSetMaybe(i)
+	b.set[i>>log2WordSize] |= 1 << (i & (wordSize - 1))
+	return b
+}
+
+// Clear bit i to 0
+func (b *BitSet) Clear(i uint) *BitSet {
+	if i >= b.length {
+		return b
+	}
+	b.set[i>>log2WordSize] &^= 1 << (i & (wordSize - 1))
+	return b
+}
+
+// SetTo sets bit i to value.
+// If i>= Cap(), this function will panic.
+// Warning: using a very large value for 'i'
+// may lead to a memory shortage and a panic: the caller is responsible
+// for providing sensible parameters in line with their memory capacity.
+func (b *BitSet) SetTo(i uint, value bool) *BitSet {
+	if value {
+		return b.Set(i)
+	}
+	return b.Clear(i)
+}
+
+// Flip bit at i.
+// If i>= Cap(), this function will panic.
+// Warning: using a very large value for 'i'
+// may lead to a memory shortage and a panic: the caller is responsible
+// for providing sensible parameters in line with their memory capacity.
+func (b *BitSet) Flip(i uint) *BitSet {
+	if i >= b.length {
+		return b.Set(i)
+	}
+	b.set[i>>log2WordSize] ^= 1 << (i & (wordSize - 1))
+	return b
+}
+
+// FlipRange bit in [start, end).
+// If end>= Cap(), this function will panic.
+// Warning: using a very large value for 'end'
+// may lead to a memory shortage and a panic: the caller is responsible
+// for providing sensible parameters in line with their memory capacity.
+func (b *BitSet) FlipRange(start, end uint) *BitSet {
+	if start >= end {
+		return b
+	}
+
+	b.extendSetMaybe(end - 1)
+	var startWord uint = start >> log2WordSize
+	var endWord uint = end >> log2WordSize
+	b.set[startWord] ^= ^(^uint64(0) << (start & (wordSize - 1)))
+	for i := startWord; i < endWord; i++ {
+		b.set[i] = ^b.set[i]
+	}
+	b.set[endWord] ^= ^uint64(0) >> (-end & (wordSize - 1))
+	return b
+}
+
+// Shrink shrinks BitSet so that the provided value is the last possible
+// set value. It clears all bits > the provided index and reduces the size
+// and length of the set.
+//
+// Note that the parameter value is not the new length in bits: it is the
+// maximal value that can be stored in the bitset after the function call.
+// The new length in bits is the parameter value + 1. Thus it is not possible
+// to use this function to set the length to 0, the minimal value of the length
+// after this function call is 1.
+//
+// A new slice is allocated to store the new bits, so you may see an increase in
+// memory usage until the GC runs. Normally this should not be a problem, but if you
+// have an extremely large BitSet its important to understand that the old BitSet will
+// remain in memory until the GC frees it.
+func (b *BitSet) Shrink(lastbitindex uint) *BitSet {
+	length := lastbitindex + 1
+	idx := wordsNeeded(length)
+	if idx > len(b.set) {
+		return b
+	}
+	shrunk := make([]uint64, idx)
+	copy(shrunk, b.set[:idx])
+	b.set = shrunk
+	b.length = length
+	b.set[idx-1] &= (allBits >> (uint64(64) - uint64(length&(wordSize-1))))
+	return b
+}
+
+// Compact shrinks BitSet to so that we preserve all set bits, while minimizing
+// memory usage. Compact calls Shrink.
+func (b *BitSet) Compact() *BitSet {
+	idx := len(b.set) - 1
+	for ; idx >= 0 && b.set[idx] == 0; idx-- {
+	}
+	newlength := uint((idx + 1) << log2WordSize)
+	if newlength >= b.length {
+		return b // nothing to do
+	}
+	if newlength > 0 {
+		return b.Shrink(newlength - 1)
+	}
+	// We preserve one word
+	return b.Shrink(63)
+}
+
+// InsertAt takes an index which indicates where a bit should be
+// inserted. Then it shifts all the bits in the set to the left by 1, starting
+// from the given index position, and sets the index position to 0.
+//
+// Depending on the size of your BitSet, and where you are inserting the new entry,
+// this method could be extremely slow and in some cases might cause the entire BitSet
+// to be recopied.
+func (b *BitSet) InsertAt(idx uint) *BitSet {
+	insertAtElement := (idx >> log2WordSize)
+
+	// if length of set is a multiple of wordSize we need to allocate more space first
+	if b.isLenExactMultiple() {
+		b.set = append(b.set, uint64(0))
+	}
+
+	var i uint
+	for i = uint(len(b.set) - 1); i > insertAtElement; i-- {
+		// all elements above the position where we want to insert can simply by shifted
+		b.set[i] <<= 1
+
+		// we take the most significant bit of the previous element and set it as
+		// the least significant bit of the current element
+		b.set[i] |= (b.set[i-1] & 0x8000000000000000) >> 63
+	}
+
+	// generate a mask to extract the data that we need to shift left
+	// within the element where we insert a bit
+	dataMask := ^(uint64(1)<<uint64(idx&(wordSize-1)) - 1)
+
+	// extract that data that we'll shift
+	data := b.set[i] & dataMask
+
+	// set the positions of the data mask to 0 in the element where we insert
+	b.set[i] &= ^dataMask
+
+	// shift data mask to the left and insert its data to the slice element
+	b.set[i] |= data << 1
+
+	// add 1 to length of BitSet
+	b.length++
+
+	return b
+}
+
+// String creates a string representation of the Bitmap
+func (b *BitSet) String() string {
+	// follows code from https://github.com/RoaringBitmap/roaring
+	var buffer bytes.Buffer
+	start := []byte("{")
+	buffer.Write(start)
+	counter := 0
+	i, e := b.NextSet(0)
+	for e {
+		counter = counter + 1
+		// to avoid exhausting the memory
+		if counter > 0x40000 {
+			buffer.WriteString("...")
+			break
+		}
+		buffer.WriteString(strconv.FormatInt(int64(i), 10))
+		i, e = b.NextSet(i + 1)
+		if e {
+			buffer.WriteString(",")
+		}
+	}
+	buffer.WriteString("}")
+	return buffer.String()
+}
+
+// DeleteAt deletes the bit at the given index position from
+// within the bitset
+// All the bits residing on the left of the deleted bit get
+// shifted right by 1
+// The running time of this operation may potentially be
+// relatively slow, O(length)
+func (b *BitSet) DeleteAt(i uint) *BitSet {
+	// the index of the slice element where we'll delete a bit
+	deleteAtElement := i >> log2WordSize
+
+	// generate a mask for the data that needs to be shifted right
+	// within that slice element that gets modified
+	dataMask := ^((uint64(1) << (i & (wordSize - 1))) - 1)
+
+	// extract the data that we'll shift right from the slice element
+	data := b.set[deleteAtElement] & dataMask
+
+	// set the masked area to 0 while leaving the rest as it is
+	b.set[deleteAtElement] &= ^dataMask
+
+	// shift the previously extracted data to the right and then
+	// set it in the previously masked area
+	b.set[deleteAtElement] |= (data >> 1) & dataMask
+
+	// loop over all the consecutive slice elements to copy each
+	// lowest bit into the highest position of the previous element,
+	// then shift the entire content to the right by 1
+	for i := int(deleteAtElement) + 1; i < len(b.set); i++ {
+		b.set[i-1] |= (b.set[i] & 1) << 63
+		b.set[i] >>= 1
+	}
+
+	b.length = b.length - 1
+
+	return b
+}
+
+// NextSet returns the next bit set from the specified index,
+// including possibly the current index
+// along with an error code (true = valid, false = no set bit found)
+// for i,e := v.NextSet(0); e; i,e = v.NextSet(i + 1) {...}
+//
+// Users concerned with performance may want to use NextSetMany to
+// retrieve several values at once.
+func (b *BitSet) NextSet(i uint) (uint, bool) {
+	x := int(i >> log2WordSize)
+	if x >= len(b.set) {
+		return 0, false
+	}
+	w := b.set[x]
+	w = w >> (i & (wordSize - 1))
+	if w != 0 {
+		return i + trailingZeroes64(w), true
+	}
+	x = x + 1
+	for x < len(b.set) {
+		if b.set[x] != 0 {
+			return uint(x)*wordSize + trailingZeroes64(b.set[x]), true
+		}
+		x = x + 1
+
+	}
+	return 0, false
+}
+
+// NextSetMany returns many next bit sets from the specified index,
+// including possibly the current index and up to cap(buffer).
+// If the returned slice has len zero, then no more set bits were found
+//
+//    buffer := make([]uint, 256) // this should be reused
+//    j := uint(0)
+//    j, buffer = bitmap.NextSetMany(j, buffer)
+//    for ; len(buffer) > 0; j, buffer = bitmap.NextSetMany(j,buffer) {
+//     for k := range buffer {
+//      do something with buffer[k]
+//     }
+//     j += 1
+//    }
+//
+//
+// It is possible to retrieve all set bits as follow:
+//
+//    indices := make([]uint, bitmap.Count())
+//    bitmap.NextSetMany(0, indices)
+//
+// However if bitmap.Count() is large, it might be preferable to
+// use several calls to NextSetMany, for performance reasons.
+func (b *BitSet) NextSetMany(i uint, buffer []uint) (uint, []uint) {
+	myanswer := buffer
+	capacity := cap(buffer)
+	x := int(i >> log2WordSize)
+	if x >= len(b.set) || capacity == 0 {
+		return 0, myanswer[:0]
+	}
+	skip := i & (wordSize - 1)
+	word := b.set[x] >> skip
+	myanswer = myanswer[:capacity]
+	size := int(0)
+	for word != 0 {
+		r := trailingZeroes64(word)
+		t := word & ((^word) + 1)
+		myanswer[size] = r + i
+		size++
+		if size == capacity {
+			goto End
+		}
+		word = word ^ t
+	}
+	x++
+	for idx, word := range b.set[x:] {
+		for word != 0 {
+			r := trailingZeroes64(word)
+			t := word & ((^word) + 1)
+			myanswer[size] = r + (uint(x+idx) << 6)
+			size++
+			if size == capacity {
+				goto End
+			}
+			word = word ^ t
+		}
+	}
+End:
+	if size > 0 {
+		return myanswer[size-1], myanswer[:size]
+	}
+	return 0, myanswer[:0]
+}
+
+// NextClear returns the next clear bit from the specified index,
+// including possibly the current index
+// along with an error code (true = valid, false = no bit found i.e. all bits are set)
+func (b *BitSet) NextClear(i uint) (uint, bool) {
+	x := int(i >> log2WordSize)
+	if x >= len(b.set) {
+		return 0, false
+	}
+	w := b.set[x]
+	w = w >> (i & (wordSize - 1))
+	wA := allBits >> (i & (wordSize - 1))
+	index := i + trailingZeroes64(^w)
+	if w != wA && index < b.length {
+		return index, true
+	}
+	x++
+	for x < len(b.set) {
+		index = uint(x)*wordSize + trailingZeroes64(^b.set[x])
+		if b.set[x] != allBits && index < b.length {
+			return index, true
+		}
+		x++
+	}
+	return 0, false
+}
+
+// ClearAll clears the entire BitSet
+func (b *BitSet) ClearAll() *BitSet {
+	if b != nil && b.set != nil {
+		for i := range b.set {
+			b.set[i] = 0
+		}
+	}
+	return b
+}
+
+// wordCount returns the number of words used in a bit set
+func (b *BitSet) wordCount() int {
+	return len(b.set)
+}
+
+// Clone this BitSet
+func (b *BitSet) Clone() *BitSet {
+	c := New(b.length)
+	if b.set != nil { // Clone should not modify current object
+		copy(c.set, b.set)
+	}
+	return c
+}
+
+// Copy into a destination BitSet
+// Returning the size of the destination BitSet
+// like array copy
+func (b *BitSet) Copy(c *BitSet) (count uint) {
+	if c == nil {
+		return
+	}
+	if b.set != nil { // Copy should not modify current object
+		copy(c.set, b.set)
+	}
+	count = c.length
+	if b.length < c.length {
+		count = b.length
+	}
+	return
+}
+
+// Count (number of set bits).
+// Also known as "popcount" or "population count".
+func (b *BitSet) Count() uint {
+	if b != nil && b.set != nil {
+		return uint(popcntSlice(b.set))
+	}
+	return 0
+}
+
+// Equal tests the equivalence of two BitSets.
+// False if they are of different sizes, otherwise true
+// only if all the same bits are set
+func (b *BitSet) Equal(c *BitSet) bool {
+	if c == nil || b == nil {
+		return c == b
+	}
+	if b.length != c.length {
+		return false
+	}
+	if b.length == 0 { // if they have both length == 0, then could have nil set
+		return true
+	}
+	// testing for equality shoud not transform the bitset (no call to safeSet)
+
+	for p, v := range b.set {
+		if c.set[p] != v {
+			return false
+		}
+	}
+	return true
+}
+
+func panicIfNull(b *BitSet) {
+	if b == nil {
+		panic(Error("BitSet must not be null"))
+	}
+}
+
+// Difference of base set and other set
+// This is the BitSet equivalent of &^ (and not)
+func (b *BitSet) Difference(compare *BitSet) (result *BitSet) {
+	panicIfNull(b)
+	panicIfNull(compare)
+	result = b.Clone() // clone b (in case b is bigger than compare)
+	l := int(compare.wordCount())
+	if l > int(b.wordCount()) {
+		l = int(b.wordCount())
+	}
+	for i := 0; i < l; i++ {
+		result.set[i] = b.set[i] &^ compare.set[i]
+	}
+	return
+}
+
+// DifferenceCardinality computes the cardinality of the differnce
+func (b *BitSet) DifferenceCardinality(compare *BitSet) uint {
+	panicIfNull(b)
+	panicIfNull(compare)
+	l := int(compare.wordCount())
+	if l > int(b.wordCount()) {
+		l = int(b.wordCount())
+	}
+	cnt := uint64(0)
+	cnt += popcntMaskSlice(b.set[:l], compare.set[:l])
+	cnt += popcntSlice(b.set[l:])
+	return uint(cnt)
+}
+
+// InPlaceDifference computes the difference of base set and other set
+// This is the BitSet equivalent of &^ (and not)
+func (b *BitSet) InPlaceDifference(compare *BitSet) {
+	panicIfNull(b)
+	panicIfNull(compare)
+	l := int(compare.wordCount())
+	if l > int(b.wordCount()) {
+		l = int(b.wordCount())
+	}
+	for i := 0; i < l; i++ {
+		b.set[i] &^= compare.set[i]
+	}
+}
+
+// Convenience function: return two bitsets ordered by
+// increasing length. Note: neither can be nil
+func sortByLength(a *BitSet, b *BitSet) (ap *BitSet, bp *BitSet) {
+	if a.length <= b.length {
+		ap, bp = a, b
+	} else {
+		ap, bp = b, a
+	}
+	return
+}
+
+// Intersection of base set and other set
+// This is the BitSet equivalent of & (and)
+func (b *BitSet) Intersection(compare *BitSet) (result *BitSet) {
+	panicIfNull(b)
+	panicIfNull(compare)
+	b, compare = sortByLength(b, compare)
+	result = New(b.length)
+	for i, word := range b.set {
+		result.set[i] = word & compare.set[i]
+	}
+	return
+}
+
+// IntersectionCardinality computes the cardinality of the union
+func (b *BitSet) IntersectionCardinality(compare *BitSet) uint {
+	panicIfNull(b)
+	panicIfNull(compare)
+	b, compare = sortByLength(b, compare)
+	cnt := popcntAndSlice(b.set, compare.set)
+	return uint(cnt)
+}
+
+// InPlaceIntersection destructively computes the intersection of
+// base set and the compare set.
+// This is the BitSet equivalent of & (and)
+func (b *BitSet) InPlaceIntersection(compare *BitSet) {
+	panicIfNull(b)
+	panicIfNull(compare)
+	l := int(compare.wordCount())
+	if l > int(b.wordCount()) {
+		l = int(b.wordCount())
+	}
+	for i := 0; i < l; i++ {
+		b.set[i] &= compare.set[i]
+	}
+	for i := l; i < len(b.set); i++ {
+		b.set[i] = 0
+	}
+	if compare.length > 0 {
+		b.extendSetMaybe(compare.length - 1)
+	}
+}
+
+// Union of base set and other set
+// This is the BitSet equivalent of | (or)
+func (b *BitSet) Union(compare *BitSet) (result *BitSet) {
+	panicIfNull(b)
+	panicIfNull(compare)
+	b, compare = sortByLength(b, compare)
+	result = compare.Clone()
+	for i, word := range b.set {
+		result.set[i] = word | compare.set[i]
+	}
+	return
+}
+
+// UnionCardinality computes the cardinality of the uniton of the base set
+// and the compare set.
+func (b *BitSet) UnionCardinality(compare *BitSet) uint {
+	panicIfNull(b)
+	panicIfNull(compare)
+	b, compare = sortByLength(b, compare)
+	cnt := popcntOrSlice(b.set, compare.set)
+	if len(compare.set) > len(b.set) {
+		cnt += popcntSlice(compare.set[len(b.set):])
+	}
+	return uint(cnt)
+}
+
+// InPlaceUnion creates the destructive union of base set and compare set.
+// This is the BitSet equivalent of | (or).
+func (b *BitSet) InPlaceUnion(compare *BitSet) {
+	panicIfNull(b)
+	panicIfNull(compare)
+	l := int(compare.wordCount())
+	if l > int(b.wordCount()) {
+		l = int(b.wordCount())
+	}
+	if compare.length > 0 {
+		b.extendSetMaybe(compare.length - 1)
+	}
+	for i := 0; i < l; i++ {
+		b.set[i] |= compare.set[i]
+	}
+	if len(compare.set) > l {
+		for i := l; i < len(compare.set); i++ {
+			b.set[i] = compare.set[i]
+		}
+	}
+}
+
+// SymmetricDifference of base set and other set
+// This is the BitSet equivalent of ^ (xor)
+func (b *BitSet) SymmetricDifference(compare *BitSet) (result *BitSet) {
+	panicIfNull(b)
+	panicIfNull(compare)
+	b, compare = sortByLength(b, compare)
+	// compare is bigger, so clone it
+	result = compare.Clone()
+	for i, word := range b.set {
+		result.set[i] = word ^ compare.set[i]
+	}
+	return
+}
+
+// SymmetricDifferenceCardinality computes the cardinality of the symmetric difference
+func (b *BitSet) SymmetricDifferenceCardinality(compare *BitSet) uint {
+	panicIfNull(b)
+	panicIfNull(compare)
+	b, compare = sortByLength(b, compare)
+	cnt := popcntXorSlice(b.set, compare.set)
+	if len(compare.set) > len(b.set) {
+		cnt += popcntSlice(compare.set[len(b.set):])
+	}
+	return uint(cnt)
+}
+
+// InPlaceSymmetricDifference creates the destructive SymmetricDifference of base set and other set
+// This is the BitSet equivalent of ^ (xor)
+func (b *BitSet) InPlaceSymmetricDifference(compare *BitSet) {
+	panicIfNull(b)
+	panicIfNull(compare)
+	l := int(compare.wordCount())
+	if l > int(b.wordCount()) {
+		l = int(b.wordCount())
+	}
+	if compare.length > 0 {
+		b.extendSetMaybe(compare.length - 1)
+	}
+	for i := 0; i < l; i++ {
+		b.set[i] ^= compare.set[i]
+	}
+	if len(compare.set) > l {
+		for i := l; i < len(compare.set); i++ {
+			b.set[i] = compare.set[i]
+		}
+	}
+}
+
+// Is the length an exact multiple of word sizes?
+func (b *BitSet) isLenExactMultiple() bool {
+	return b.length%wordSize == 0
+}
+
+// Clean last word by setting unused bits to 0
+func (b *BitSet) cleanLastWord() {
+	if !b.isLenExactMultiple() {
+		b.set[len(b.set)-1] &= allBits >> (wordSize - b.length%wordSize)
+	}
+}
+
+// Complement computes the (local) complement of a biset (up to length bits)
+func (b *BitSet) Complement() (result *BitSet) {
+	panicIfNull(b)
+	result = New(b.length)
+	for i, word := range b.set {
+		result.set[i] = ^word
+	}
+	result.cleanLastWord()
+	return
+}
+
+// All returns true if all bits are set, false otherwise. Returns true for
+// empty sets.
+func (b *BitSet) All() bool {
+	panicIfNull(b)
+	return b.Count() == b.length
+}
+
+// None returns true if no bit is set, false otherwise. Returns true for
+// empty sets.
+func (b *BitSet) None() bool {
+	panicIfNull(b)
+	if b != nil && b.set != nil {
+		for _, word := range b.set {
+			if word > 0 {
+				return false
+			}
+		}
+		return true
+	}
+	return true
+}
+
+// Any returns true if any bit is set, false otherwise
+func (b *BitSet) Any() bool {
+	panicIfNull(b)
+	return !b.None()
+}
+
+// IsSuperSet returns true if this is a superset of the other set
+func (b *BitSet) IsSuperSet(other *BitSet) bool {
+	for i, e := other.NextSet(0); e; i, e = other.NextSet(i + 1) {
+		if !b.Test(i) {
+			return false
+		}
+	}
+	return true
+}
+
+// IsStrictSuperSet returns true if this is a strict superset of the other set
+func (b *BitSet) IsStrictSuperSet(other *BitSet) bool {
+	return b.Count() > other.Count() && b.IsSuperSet(other)
+}
+
+// DumpAsBits dumps a bit set as a string of bits
+func (b *BitSet) DumpAsBits() string {
+	if b.set == nil {
+		return "."
+	}
+	buffer := bytes.NewBufferString("")
+	i := len(b.set) - 1
+	for ; i >= 0; i-- {
+		fmt.Fprintf(buffer, "%064b.", b.set[i])
+	}
+	return buffer.String()
+}
+
+// BinaryStorageSize returns the binary storage requirements
+func (b *BitSet) BinaryStorageSize() int {
+	return binary.Size(uint64(0)) + binary.Size(b.set)
+}
+
+// WriteTo writes a BitSet to a stream
+func (b *BitSet) WriteTo(stream io.Writer) (int64, error) {
+	length := uint64(b.length)
+
+	// Write length
+	err := binary.Write(stream, binaryOrder, length)
+	if err != nil {
+		return 0, err
+	}
+
+	// Write set
+	err = binary.Write(stream, binaryOrder, b.set)
+	return int64(b.BinaryStorageSize()), err
+}
+
+// ReadFrom reads a BitSet from a stream written using WriteTo
+func (b *BitSet) ReadFrom(stream io.Reader) (int64, error) {
+	var length uint64
+
+	// Read length first
+	err := binary.Read(stream, binaryOrder, &length)
+	if err != nil {
+		return 0, err
+	}
+	newset := New(uint(length))
+
+	if uint64(newset.length) != length {
+		return 0, errors.New("unmarshalling error: type mismatch")
+	}
+
+	// Read remaining bytes as set
+	err = binary.Read(stream, binaryOrder, newset.set)
+	if err != nil {
+		return 0, err
+	}
+
+	*b = *newset
+	return int64(b.BinaryStorageSize()), nil
+}
+
+// MarshalBinary encodes a BitSet into a binary form and returns the result.
+func (b *BitSet) MarshalBinary() ([]byte, error) {
+	var buf bytes.Buffer
+	writer := bufio.NewWriter(&buf)
+
+	_, err := b.WriteTo(writer)
+	if err != nil {
+		return []byte{}, err
+	}
+
+	err = writer.Flush()
+
+	return buf.Bytes(), err
+}
+
+// UnmarshalBinary decodes the binary form generated by MarshalBinary.
+func (b *BitSet) UnmarshalBinary(data []byte) error {
+	buf := bytes.NewReader(data)
+	reader := bufio.NewReader(buf)
+
+	_, err := b.ReadFrom(reader)
+
+	return err
+}
+
+// MarshalJSON marshals a BitSet as a JSON structure
+func (b *BitSet) MarshalJSON() ([]byte, error) {
+	buffer := bytes.NewBuffer(make([]byte, 0, b.BinaryStorageSize()))
+	_, err := b.WriteTo(buffer)
+	if err != nil {
+		return nil, err
+	}
+
+	// URLEncode all bytes
+	return json.Marshal(base64Encoding.EncodeToString(buffer.Bytes()))
+}
+
+// UnmarshalJSON unmarshals a BitSet from JSON created using MarshalJSON
+func (b *BitSet) UnmarshalJSON(data []byte) error {
+	// Unmarshal as string
+	var s string
+	err := json.Unmarshal(data, &s)
+	if err != nil {
+		return err
+	}
+
+	// URLDecode string
+	buf, err := base64Encoding.DecodeString(s)
+	if err != nil {
+		return err
+	}
+
+	_, err = b.ReadFrom(bytes.NewReader(buf))
+	return err
+}