vendor in containers/storage v1.29.0

Signed-off-by: Daniel J Walsh <dwalsh@redhat.com>

3 files changed, 832 insertions, 0 deletions

diff --git a/vendor/github.com/google/go-intervals/LICENSE b/vendor/github.com/google/go-intervals/LICENSE
new file mode 100644
index 000000000..d64569567
--- /dev/null
+++ b/vendor/github.com/google/go-intervals/LICENSE
@@ -0,0 +1,202 @@
+
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diff --git a/vendor/github.com/google/go-intervals/intervalset/intervalset.go b/vendor/github.com/google/go-intervals/intervalset/intervalset.go
new file mode 100644
index 000000000..6a33db63c
--- /dev/null
+++ b/vendor/github.com/google/go-intervals/intervalset/intervalset.go
@@ -0,0 +1,545 @@
+// Copyright 2017 Google Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package intervalset provides an abtraction for dealing with sets of
+// 1-dimensional spans, such as sets of time ranges. The Set type provides set
+// arithmetic and enumeration methods based on an Interval interface.
+//
+// DISCLAIMER: This library is not yet stable, so expect breaking changes.
+package intervalset
+
+import (
+	"fmt"
+	"sort"
+	"strings"
+)
+
+// Interval is the interface for a continuous or discrete span. The interval is
+// assumed to be inclusive of the starting point and exclusive of the ending
+// point.
+//
+// All methods in the interface are non-destructive: Calls to the methods should
+// not modify the interval. Furthermore, the implementation assumes an interval
+// will not be mutated by user code, either.
+type Interval interface {
+	// Intersect returns the intersection of an interval with another
+	// interval. The function may panic if the other interval is incompatible.
+	Intersect(Interval) Interval
+
+	// Before returns true if the interval is completely before another interval.
+	Before(Interval) bool
+
+	// IsZero returns true for the zero value of an interval.
+	IsZero() bool
+
+	// Bisect returns two intervals, one on the lower side of x and one on the
+	// upper side of x, corresponding to the subtraction of x from the original
+	// interval. The returned intervals are always within the range of the
+	// original interval.
+	Bisect(x Interval) (Interval, Interval)
+
+	// Adjoin returns the union of two intervals, if the intervals are exactly
+	// adjacent, or the zero interval if they are not.
+	Adjoin(Interval) Interval
+
+	// Encompass returns an interval that covers the exact extents of two
+	// intervals.
+	Encompass(Interval) Interval
+}
+
+// Set is a set of interval objects used for
+type Set struct {
+	//non-overlapping intervals
+	intervals []Interval
+	// factory is needed when the extents of the empty set are needed.
+	factory intervalFactory
+}
+
+// SetInput is an interface implemented by Set and ImmutableSet. It is used when
+// one of these types type must take a set as an argument.
+type SetInput interface {
+	// Extent returns the Interval defined by the minimum and maximum values of
+	// the set.
+	Extent() Interval
+
+	// IntervalsBetween iterates over the intervals within extents set and calls f
+	// with each. If f returns false, iteration ceases.
+	//
+	// Any interval within the set that overlaps partially with extents is truncated
+	// before being passed to f.
+	IntervalsBetween(extents Interval, f IntervalReceiver)
+}
+
+// NewSet returns a new set given a sorted slice of intervals. This function
+// panics if the intervals are not sorted.
+func NewSet(intervals []Interval) *Set {
+	return NewSetV1(intervals, oldBehaviorFactory.makeZero)
+}
+
+// NewSetV1 returns a new set given a sorted slice of intervals. This function
+// panics if the intervals are not sorted.
+//
+// NewSetV1 will be renamed and will replace NewSet in the v1 release.
+func NewSetV1(intervals []Interval, makeZero func() Interval) *Set {
+	if err := CheckSorted(intervals); err != nil {
+		panic(err)
+	}
+	return &Set{intervals, makeIntervalFactor(makeZero)}
+}
+
+// CheckSorted checks that interval[i+1] is not before interval[i] for all
+// relevant elements of the input slice. Nil is returned when len(intervals) is
+// 0 or 1.
+func CheckSorted(intervals []Interval) error {
+	for i := 0; i < len(intervals)-1; i++ {
+		if !intervals[i].Before(intervals[i+1]) {
+			return fmt.Errorf("!intervals[%d].Before(intervals[%d]) for %s, %s", i, i+1, intervals[i], intervals[i+1])
+		}
+	}
+	return nil
+}
+
+// Empty returns a new, empty set of intervals.
+func Empty() *Set {
+	return EmptyV1(oldBehaviorFactory.makeZero)
+}
+
+// EmptyV1 returns a new, empty set of intervals using the semantics of the V1
+// API, which will require a factory method for construction of an empty interval.
+func EmptyV1(makeZero func() Interval) *Set {
+	return &Set{nil, makeIntervalFactor(makeZero)}
+}
+
+// Copy returns a copy of a set that may be mutated without affecting the original.
+func (s *Set) Copy() *Set {
+	return &Set{append([]Interval(nil), s.intervals...), s.factory}
+}
+
+// String returns a human-friendly representation of the set.
+func (s *Set) String() string {
+	var strs []string
+	for _, x := range s.intervals {
+		strs = append(strs, fmt.Sprintf("%s", x))
+	}
+	return fmt.Sprintf("{%s}", strings.Join(strs, ", "))
+}
+
+// Extent returns the Interval defined by the minimum and maximum values of the
+// set.
+func (s *Set) Extent() Interval {
+	if len(s.intervals) == 0 {
+		return s.factory.makeZero()
+	}
+	return s.intervals[0].Encompass(s.intervals[len(s.intervals)-1])
+}
+
+// Add adds all the elements of another set to this set.
+func (s *Set) Add(b SetInput) {
+	// Deal with nil extent. See https://github.com/google/go-intervals/issues/6.
+	bExtent := b.Extent()
+	if bExtent == nil {
+		return // no changes needed
+	}
+
+	// Loop through the intervals of x
+	b.IntervalsBetween(bExtent, func(x Interval) bool {
+		s.insert(x)
+		return true
+	})
+}
+
+// Contains reports whether an interval is entirely contained by the set.
+func (s *Set) Contains(ival Interval) bool {
+	// Loop through the intervals of x
+	next := s.iterator(ival, true)
+	for setInterval := next(); setInterval != nil; setInterval = next() {
+		left, right := ival.Bisect(setInterval)
+		if !left.IsZero() {
+			return false
+		}
+		ival = right
+	}
+	return ival.IsZero()
+}
+
+// adjoinOrAppend adds an interval to the end of intervals unless that value
+// directly adjoins the last element of intervals, in which case the last
+// element will be replaced by the adjoined interval.
+func adjoinOrAppend(intervals []Interval, x Interval) []Interval {
+	lastIndex := len(intervals) - 1
+	if lastIndex == -1 {
+		return append(intervals, x)
+	}
+	adjoined := intervals[lastIndex].Adjoin(x)
+	if adjoined.IsZero() {
+		return append(intervals, x)
+	}
+	intervals[lastIndex] = adjoined
+	return intervals
+}
+
+func (s *Set) insert(insertion Interval) {
+	if s.Contains(insertion) {
+		return
+	}
+	// TODO(reddaly): Something like Java's ArrayList would allow both O(log(n))
+	// insertion and O(log(n)) lookup. For now, we have O(log(n)) lookup and O(n)
+	// insertion.
+	var newIntervals []Interval
+	push := func(x Interval) {
+		newIntervals = adjoinOrAppend(newIntervals, x)
+	}
+	inserted := false
+	for _, x := range s.intervals {
+		if inserted {
+			push(x)
+			continue
+		}
+		if insertion.Before(x) {
+			push(insertion)
+			push(x)
+			inserted = true
+			continue
+		}
+		// [===left===)[==x===)[===right===)
+		left, right := insertion.Bisect(x)
+		if !left.IsZero() {
+			push(left)
+		}
+		push(x)
+		// Replace the interval being inserted with the remaining portion of the
+		// interval to be inserted.
+		if right.IsZero() {
+			inserted = true
+		} else {
+			insertion = right
+		}
+	}
+	if !inserted {
+		push(insertion)
+	}
+	s.intervals = newIntervals
+}
+
+// Sub destructively modifies the set by subtracting b.
+func (s *Set) Sub(b SetInput) {
+	extent := s.Extent()
+	// Deal with nil extent. See https://github.com/google/go-intervals/issues/6.
+	if extent == nil {
+		// Set is already empty, no changes necessary.
+		return
+	}
+	var newIntervals []Interval
+	push := func(x Interval) {
+		newIntervals = adjoinOrAppend(newIntervals, x)
+	}
+	nextX := s.iterator(extent, true)
+	nextY, cancel := setIntervalIterator(b, extent)
+	defer cancel()
+
+	x := nextX()
+	y := nextY()
+	for x != nil {
+		// If y == nil, all of the remaining intervals in A are to the right of B,
+		// so just yield them.
+		if y == nil {
+			push(x)
+			x = nextX()
+			continue
+		}
+		// Split x into parts left and right of y.
+		// The diagrams below show the bisection results for various situations.
+		// if left.IsZero() && !right.IsZero()
+		//             xxx
+		// y1y1 y2y2 y3  y4y4
+		//             xxx
+		// or
+		//   xxxxxxxxxxxx
+		// y1y1 y2y2 y3  y4y4
+		//
+		// if !left.IsZero() && !right.IsZero()
+		//       x1x1x1x1x1
+		//         y1  y2
+		//
+		// if left.IsZero() && right.IsZero()
+		//    x1x1x1x1  x2x2x2
+		//  y1y1y1y1y1y1y1
+		//
+		// if !left.IsZero() && right.IsZero()
+		//   x1x1  x2
+		//     y1y1y1y1
+		left, right := x.Bisect(y)
+
+		// If the left side of x is non-zero, it can definitely be pushed to the
+		// resulting interval set since no subsequent y value will intersect it.
+		// The sequences look something like
+		//         x1x1x1x1x1       OR   x1x1x1 x2
+		//             y1 y2                       y1y1y1
+		// left  = x1x1                  x1x1x1
+		// right =       x1x1                            {zero}
+		if !left.IsZero() {
+			push(left)
+		}
+
+		if !right.IsZero() {
+			// If the right side of x is non-zero:
+			// 1) Right is the remaining portion of x that needs to be pushed.
+			x = right
+			// 2) It's not possible for current y to intersect it, so advance y. It's
+			//    possible nextY() will intersect it, so don't push yet.
+			y = nextY()
+		} else {
+			// There's nothing left of x to push, so advance x.
+			x = nextX()
+		}
+	}
+
+	// Setting s.intervals is the only side effect in this function.
+	s.intervals = newIntervals
+}
+
+// intersectionIterator returns a function that yields intervals that are
+// members of the intersection of s and b, in increasing order.
+func (s *Set) intersectionIterator(b SetInput) (iter func() Interval, cancel func()) {
+	return intervalMapperToIterator(func(f IntervalReceiver) {
+		sExtent, bExtent := s.Extent(), b.Extent()
+		// Deal with nil extent. See https://github.com/google/go-intervals/issues/6.
+		if sExtent == nil || bExtent == nil {
+			// IF either set is already empty, the intersection is empty. This
+			// voids a panic below where a valid Interval is needed for each
+			// extent.
+			return
+		}
+		nextX := s.iterator(bExtent, true)
+		nextY, cancel := setIntervalIterator(b, sExtent)
+		defer cancel()
+
+		x := nextX()
+		y := nextY()
+		// Loop through corresponding intervals of S and B.
+		// If y == nil, all of the remaining intervals in S are to the right of B.
+		// If x == nil, all of the remaining intervals in B are to the right of S.
+		for x != nil && y != nil {
+			if x.Before(y) {
+				x = nextX()
+				continue
+			}
+			if y.Before(x) {
+				y = nextY()
+				continue
+			}
+			xyIntersect := x.Intersect(y)
+			if !xyIntersect.IsZero() {
+				if !f(xyIntersect) {
+					return
+				}
+				_, right := x.Bisect(y)
+				if !right.IsZero() {
+					x = right
+				} else {
+					x = nextX()
+				}
+			}
+		}
+	})
+}
+
+// Intersect destructively modifies the set by intersectin it with b.
+func (s *Set) Intersect(b SetInput) {
+	iter, cancel := s.intersectionIterator(b)
+	defer cancel()
+	var newIntervals []Interval
+	for x := iter(); x != nil; x = iter() {
+		newIntervals = append(newIntervals, x)
+	}
+	s.intervals = newIntervals
+}
+
+// searchLow returns the first index in s.intervals that is not before x.
+func (s *Set) searchLow(x Interval) int {
+	return sort.Search(len(s.intervals), func(i int) bool {
+		return !s.intervals[i].Before(x)
+	})
+}
+
+// searchLow returns the index of the first interval in s.intervals that is
+// entirely after x.
+func (s *Set) searchHigh(x Interval) int {
+	return sort.Search(len(s.intervals), func(i int) bool {
+		return x.Before(s.intervals[i])
+	})
+}
+
+// iterator returns a function that yields elements of the set in order.
+//
+// The function returned will return nil when finished iterating.
+func (s *Set) iterator(extents Interval, forward bool) func() Interval {
+	low, high := s.searchLow(extents), s.searchHigh(extents)
+
+	i, stride := low, 1
+	if !forward {
+		i, stride = high-1, -1
+	}
+
+	return func() Interval {
+		if i < 0 || i >= len(s.intervals) {
+			return nil
+		}
+		x := s.intervals[i]
+		i += stride
+		return x
+	}
+}
+
+// IntervalReceiver is a function used for iterating over a set of intervals. It
+// takes the start and end times and returns true if the iteration should
+// continue.
+type IntervalReceiver func(Interval) bool
+
+// IntervalsBetween iterates over the intervals within extents set and calls f
+// with each. If f returns false, iteration ceases.
+//
+// Any interval within the set that overlaps partially with extents is truncated
+// before being passed to f.
+func (s *Set) IntervalsBetween(extents Interval, f IntervalReceiver) {
+	// Begin = first index in s.intervals that is not before extents.
+	begin := sort.Search(len(s.intervals), func(i int) bool {
+		return !s.intervals[i].Before(extents)
+	})
+
+	// TODO(reddaly): Optimize this by performing a binary search for the ending
+	// point.
+	for _, interval := range s.intervals[begin:] {
+		// If the interval is after the extents, there will be no more overlap, so
+		// break out of the loop.
+		if extents.Before(interval) {
+			break
+		}
+		portionOfInterval := extents.Intersect(interval)
+		if portionOfInterval.IsZero() {
+			continue
+		}
+
+		if !f(portionOfInterval) {
+			return
+		}
+	}
+}
+
+// Intervals iterates over all the intervals within the set and calls f with
+// each one. If f returns false, iteration ceases.
+func (s *Set) Intervals(f IntervalReceiver) {
+	for _, interval := range s.intervals {
+		if !f(interval) {
+			return
+		}
+	}
+}
+
+// AllIntervals returns an ordered slice of all the intervals in the set.
+func (s *Set) AllIntervals() []Interval {
+	return append(make([]Interval, 0, len(s.intervals)), s.intervals...)
+}
+
+// ImmutableSet returns an immutable copy of this set.
+func (s *Set) ImmutableSet() *ImmutableSet {
+	return NewImmutableSet(s.AllIntervals())
+}
+
+// mapFn reports true if an iteration should continue. It is called on values of
+// a collection.
+type mapFn func(interface{}) bool
+
+// mapFn calls mapFn for each member of a collection.
+type mapperFn func(mapFn)
+
+// iteratorFn returns the next item in an iteration or the zero value. The
+// second return value indicates whether the first return value is a member of
+// the collection.
+type iteratorFn func() (interface{}, bool)
+
+// generatorFn returns an iterator.
+type generatorFn func() iteratorFn
+
+// cancelFn should be called to clean up the goroutine that would otherwise leak.
+type cancelFn func()
+
+// mapperToIterator returns an iteratorFn version of a mappingFn. The second
+// return value must be called at the end of iteration, or the underlying
+// goroutine will leak.
+func mapperToIterator(m mapperFn) (iteratorFn, cancelFn) {
+	generatedValues := make(chan interface{}, 1)
+	stopCh := make(chan interface{}, 1)
+	go func() {
+		m(func(obj interface{}) bool {
+			select {
+			case <-stopCh:
+				return false
+			case generatedValues <- obj:
+				return true
+			}
+		})
+		close(generatedValues)
+	}()
+	iter := func() (interface{}, bool) {
+		value, ok := <-generatedValues
+		return value, ok
+	}
+	return iter, func() {
+		stopCh <- nil
+	}
+}
+
+func intervalMapperToIterator(mapper func(IntervalReceiver)) (iter func() Interval, cancel func()) {
+	genericMapper := func(m mapFn) {
+		mapper(func(ival Interval) bool {
+			return m(ival)
+		})
+	}
+
+	genericIter, cancel := mapperToIterator(genericMapper)
+	return func() Interval {
+		genericVal, iterationEnded := genericIter()
+		if !iterationEnded {
+			return nil
+		}
+		ival, ok := genericVal.(Interval)
+		if !ok {
+			panic("unexpected value type, internal error")
+		}
+		return ival
+	}, cancel
+}
+
+func setIntervalIterator(s SetInput, extent Interval) (iter func() Interval, cancel func()) {
+	return intervalMapperToIterator(func(f IntervalReceiver) {
+		s.IntervalsBetween(extent, f)
+	})
+}
+
+// oldBehaviorFactory returns a nil interval. This was used before
+// construction of a Set/ImmutableSet required passing in a factory method for
+// creating a zero interval object.
+var oldBehaviorFactory = makeIntervalFactor(func() Interval { return nil })
+
+// intervalFactory is used to construct a zero-value interval. The zero value
+// interval may be different for different types of intervals, so a factory is
+// sometimes needed to write generic algorithms about intervals.
+type intervalFactory struct {
+	makeZero func() Interval
+}
+
+func makeIntervalFactor(makeZero func() Interval) intervalFactory {
+	return intervalFactory{makeZero}
+}
diff --git a/vendor/github.com/google/go-intervals/intervalset/intervalset_immutable.go b/vendor/github.com/google/go-intervals/intervalset/intervalset_immutable.go
new file mode 100644
index 000000000..f6d5cbb52
--- /dev/null
+++ b/vendor/github.com/google/go-intervals/intervalset/intervalset_immutable.go
@@ -0,0 +1,85 @@
+// Copyright 2017 Google Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package intervalset
+
+// ImmutableSet is a set of interval objects. It provides various set theory
+// operations.
+type ImmutableSet struct {
+	set *Set
+}
+
+// NewImmutableSet returns a new set given a sorted slice of intervals. This
+// function panics if the intervals are not sorted.
+func NewImmutableSet(intervals []Interval) *ImmutableSet {
+	return NewImmutableSetV1(intervals, oldBehaviorFactory.makeZero)
+}
+
+// NewImmutableSetV1 returns a new set given a sorted slice of intervals. This
+// function panics if the intervals are not sorted.
+func NewImmutableSetV1(intervals []Interval, makeZero func() Interval) *ImmutableSet {
+	return &ImmutableSet{NewSetV1(intervals, makeZero)}
+}
+
+// String returns a human-friendly representation of the set.
+func (s *ImmutableSet) String() string {
+	return s.set.String()
+}
+
+// Extent returns the Interval defined by the minimum and maximum values of the
+// set.
+func (s *ImmutableSet) Extent() Interval {
+	return s.set.Extent()
+}
+
+// Contains reports whether an interval is entirely contained by the set.
+func (s *ImmutableSet) Contains(ival Interval) bool {
+	return s.set.Contains(ival)
+}
+
+// Union returns a set with the contents of this set and another set.
+func (s *ImmutableSet) Union(b SetInput) *ImmutableSet {
+	union := s.set.Copy()
+	union.Add(b)
+	return &ImmutableSet{union}
+}
+
+// Sub returns a set without the intervals of another set.
+func (s *ImmutableSet) Sub(b SetInput) *ImmutableSet {
+	x := s.set.Copy()
+	x.Sub(b)
+	return &ImmutableSet{x}
+}
+
+// Intersect returns the intersection of two sets.
+func (s *ImmutableSet) Intersect(b SetInput) *ImmutableSet {
+	x := s.set.Copy()
+	x.Intersect(b)
+	return &ImmutableSet{x}
+}
+
+// IntervalsBetween iterates over the intervals within extents set and calls f
+// with each. If f returns false, iteration ceases.
+//
+// Any interval within the set that overlaps partially with extents is truncated
+// before being passed to f.
+func (s *ImmutableSet) IntervalsBetween(extents Interval, f IntervalReceiver) {
+	s.set.IntervalsBetween(extents, f)
+}
+
+// Intervals iterates over all the intervals within the set and calls f with
+// each one. If f returns false, iteration ceases.
+func (s *ImmutableSet) Intervals(f IntervalReceiver) {
+	s.set.Intervals(f)
+}