updated dependencies

vendor/github.com/RoaringBitmap/roaring/roaring.go

@@ -6,12 +6,12 @@
 package roaring
 
 import (
-	"bufio"
 	"bytes"
 	"encoding/base64"
 	"fmt"
 	"io"
 	"strconv"
+	"sync"
 )
 
 // Bitmap represents a compressed bitmap where you can add integers.
@@ -67,8 +67,14 @@ func (rb *Bitmap) WriteToMsgpack(stream io.Writer) (int64, error) {
 // The format is compatible with other RoaringBitmap
 // implementations (Java, C) and is documented here:
 // https://github.com/RoaringBitmap/RoaringFormatSpec
-func (rb *Bitmap) ReadFrom(stream io.Reader) (int64, error) {
-	return rb.highlowcontainer.readFrom(stream)
+func (rb *Bitmap) ReadFrom(reader io.Reader) (p int64, err error) {
+	stream := byteInputAdapterPool.Get().(*byteInputAdapter)
+	stream.reset(reader)
+
+	p, err = rb.highlowcontainer.readFrom(stream)
+	byteInputAdapterPool.Put(stream)
+
+	return
 }
 
 // FromBuffer creates a bitmap from its serialized version stored in buffer
@@ -87,10 +93,36 @@ func (rb *Bitmap) ReadFrom(stream io.Reader) (int64, error) {
 // You should *not* change the copy-on-write status of the resulting
 // bitmaps (SetCopyOnWrite).
 //
-func (rb *Bitmap) FromBuffer(buf []byte) (int64, error) {
-	return rb.highlowcontainer.fromBuffer(buf)
+// If buf becomes unavailable, then a bitmap created with
+// FromBuffer would be effectively broken. Furthermore, any
+// bitmap derived from this bitmap (e.g., via Or, And) might
+// also be broken. Thus, before making buf unavailable, you should
+// call CloneCopyOnWriteContainers on all such bitmaps.
+//
+func (rb *Bitmap) FromBuffer(buf []byte) (p int64, err error) {
+	stream := byteBufferPool.Get().(*byteBuffer)
+	stream.reset(buf)
+
+	p, err = rb.highlowcontainer.readFrom(stream)
+	byteBufferPool.Put(stream)
+
+	return
 }
 
+var (
+	byteBufferPool = sync.Pool{
+		New: func() interface{} {
+			return &byteBuffer{}
+		},
+	}
+
+	byteInputAdapterPool = sync.Pool{
+		New: func() interface{} {
+			return &byteInputAdapter{}
+		},
+	}
+)
+
 // RunOptimize attempts to further compress the runs of consecutive values found in the bitmap
 func (rb *Bitmap) RunOptimize() {
 	rb.highlowcontainer.runOptimize()
@@ -110,29 +142,15 @@ func (rb *Bitmap) ReadFromMsgpack(stream io.Reader) (int64, error) {
 }
 
 // MarshalBinary implements the encoding.BinaryMarshaler interface for the bitmap
+// (same as ToBytes)
 func (rb *Bitmap) MarshalBinary() ([]byte, error) {
-	var buf bytes.Buffer
-	writer := bufio.NewWriter(&buf)
-	_, err := rb.WriteTo(writer)
-	if err != nil {
-		return nil, err
-	}
-	err = writer.Flush()
-	if err != nil {
-		return nil, err
-	}
-	return buf.Bytes(), nil
+	return rb.ToBytes()
 }
 
 // UnmarshalBinary implements the encoding.BinaryUnmarshaler interface for the bitmap
 func (rb *Bitmap) UnmarshalBinary(data []byte) error {
-	var buf bytes.Buffer
-	_, err := buf.Write(data)
-	if err != nil {
-		return err
-	}
-	reader := bufio.NewReader(&buf)
-	_, err = rb.ReadFrom(reader)
+	r := bytes.NewReader(data)
+	_, err := rb.ReadFrom(r)
 	return err
 }
 
@@ -215,10 +233,20 @@ type IntIterable interface {
 	Next() uint32
 }
 
+// IntPeekable allows you to look at the next value without advancing and
+// advance as long as the next value is smaller than minval
+type IntPeekable interface {
+	IntIterable
+	// PeekNext peeks the next value without advancing the iterator
+	PeekNext() uint32
+	// AdvanceIfNeeded advances as long as the next value is smaller than minval
+	AdvanceIfNeeded(minval uint32)
+}
+
 type intIterator struct {
 	pos              int
 	hs               uint32
-	iter             shortIterable
+	iter             shortPeekable
 	highlowcontainer *roaringArray
 }
 
@@ -244,6 +272,30 @@ func (ii *intIterator) Next() uint32 {
 	return x
 }
 
+// PeekNext peeks the next value without advancing the iterator
+func (ii *intIterator) PeekNext() uint32 {
+	return uint32(ii.iter.peekNext()&maxLowBit) | ii.hs
+}
+
+// AdvanceIfNeeded advances as long as the next value is smaller than minval
+func (ii *intIterator) AdvanceIfNeeded(minval uint32) {
+	to := minval >> 16
+
+	for ii.HasNext() && (ii.hs>>16) < to {
+		ii.pos++
+		ii.init()
+	}
+
+	if ii.HasNext() && (ii.hs>>16) == to {
+		ii.iter.advanceIfNeeded(lowbits(minval))
+
+		if !ii.iter.hasNext() {
+			ii.pos++
+			ii.init()
+		}
+	}
+}
+
 func newIntIterator(a *Bitmap) *intIterator {
 	p := new(intIterator)
 	p.pos = 0
@@ -364,9 +416,9 @@ func (rb *Bitmap) String() string {
 	return buffer.String()
 }
 
-// Iterator creates a new IntIterable to iterate over the integers contained in the bitmap, in sorted order;
+// Iterator creates a new IntPeekable to iterate over the integers contained in the bitmap, in sorted order;
 // the iterator becomes invalid if the bitmap is modified (e.g., with Add or Remove).
-func (rb *Bitmap) Iterator() IntIterable {
+func (rb *Bitmap) Iterator() IntPeekable {
 	return newIntIterator(rb)
 }
 
@@ -1378,6 +1430,21 @@ func (rb *Bitmap) GetCopyOnWrite() (val bool) {
 	return rb.highlowcontainer.copyOnWrite
 }
 
+// CloneCopyOnWriteContainers clones all containers which have
+// needCopyOnWrite set to true.
+// This can be used to make sure it is safe to munmap a []byte
+// that the roaring array may still have a reference to, after
+// calling FromBuffer.
+// More generally this function is useful if you call FromBuffer
+// to construct a bitmap with a backing array buf
+// and then later discard the buf array. Note that you should call
+// CloneCopyOnWriteContainers on all bitmaps that were derived
+// from the 'FromBuffer' bitmap since they map have dependencies
+// on the buf array as well.
+func (rb *Bitmap) CloneCopyOnWriteContainers() {
+	rb.highlowcontainer.cloneCopyOnWriteContainers()
+}
+
 // FlipInt calls Flip after casting the parameters (convenience method)
 func FlipInt(bm *Bitmap, rangeStart, rangeEnd int) *Bitmap {
 	return Flip(bm, uint64(rangeStart), uint64(rangeEnd))