Replace rleplus with rlepluslazy

License: MIT
Signed-off-by: Jakub Sztandera <[email protected]>

chain/types/bitfield.go

@@ -3,19 +3,24 @@ package types
 import (
 	"fmt"
 	"io"
-	"sort"
 
-	"github.com/filecoin-project/lotus/extern/rleplus"
+	rlepluslazy "github.com/filecoin-project/lotus/lib/rlepluslazy"
 	cbg "github.com/whyrusleeping/cbor-gen"
 	"golang.org/x/xerrors"
 )
 
 type BitField struct {
+	rle rlepluslazy.RLE
+
 	bits map[uint64]struct{}
 }
 
 func NewBitField() BitField {
-	return BitField{bits: make(map[uint64]struct{})}
+	rle, _ := rlepluslazy.FromBuf([]byte{})
+	return BitField{
+		rle:  rle,
+		bits: make(map[uint64]struct{}),
+	}
 }
 
 func BitFieldFromSet(setBits []uint64) BitField {
@@ -26,31 +31,59 @@ func BitFieldFromSet(setBits []uint64) BitField {
 	return res
 }
 
+func (bf BitField) sum() (rlepluslazy.RunIterator, error) {
+	if len(bf.bits) == 0 {
+		return bf.rle.RunIterator()
+	}
+
+	a, err := bf.rle.RunIterator()
+	if err != nil {
+		return nil, err
+	}
+	slc := make([]uint64, 0, len(bf.bits))
+	for b := range bf.bits {
+		slc = append(slc, b)
+	}
+
+	b, err := rlepluslazy.RunsFromSlice(slc)
+	if err != nil {
+		return nil, err
+	}
+
+	res, err := rlepluslazy.Sum(a, b)
+	if err != nil {
+		return nil, err
+	}
+	return res, nil
+}
+
 // Set ...s bit in the BitField
 func (bf BitField) Set(bit uint64) {
 	bf.bits[bit] = struct{}{}
 }
 
-// Clear ...s bit in the BitField
-func (bf BitField) Clear(bit uint64) {
-	delete(bf.bits, bit)
-}
-
-// Has checkes if bit is set in the BitField
-func (bf BitField) Has(bit uint64) bool {
-	_, ok := bf.bits[bit]
-	return ok
+func (bf BitField) Count() (uint64, error) {
+	s, err := bf.sum()
+	if err != nil {
+		return 0, err
+	}
+	return rlepluslazy.Count(s)
 }
 
 // All returns all set bits, in random order
-func (bf BitField) All() []uint64 {
-	res := make([]uint64, 0, len(bf.bits))
-	for i := range bf.bits {
-		res = append(res, i)
+func (bf BitField) All() ([]uint64, error) {
+
+	runs, err := bf.sum()
+	if err != nil {
+		return nil, err
 	}
 
-	sort.Slice(res, func(i, j int) bool { return res[i] < res[j] })
-	return res
+	res, err := rlepluslazy.SliceFromRuns(runs)
+	if err != nil {
+		return nil, err
+	}
+
+	return res, err
 }
 
 func (bf BitField) MarshalCBOR(w io.Writer) error {
@@ -59,7 +92,12 @@ func (bf BitField) MarshalCBOR(w io.Writer) error {
 		ints = append(ints, i)
 	}
 
-	rle, _, err := rleplus.Encode(ints) // Encode sorts internally
+	s, err := bf.sum()
+	if err != nil {
+		return err
+	}
+
+	rle, err := rlepluslazy.EncodeRuns(s, []byte{})
 	if err != nil {
 		return err
 	}
@@ -88,19 +126,17 @@ func (bf *BitField) UnmarshalCBOR(r io.Reader) error {
 		return fmt.Errorf("expected byte array")
 	}
 
-	rle := make([]byte, extra)
-	if _, err := io.ReadFull(br, rle); err != nil {
+	buf := make([]byte, extra)
+	if _, err := io.ReadFull(br, buf); err != nil {
 		return err
 	}
 
-	ints, err := rleplus.Decode(rle)
+	rle, err := rlepluslazy.FromBuf(buf)
 	if err != nil {
 		return xerrors.Errorf("could not decode rle+: %w", err)
 	}
+	bf.rle = rle
 	bf.bits = make(map[uint64]struct{})
-	for _, i := range ints {
-		bf.bits[i] = struct{}{}
-	}
 
 	return nil
 }

lib/rlepluslazy/rleplus.go

@@ -16,25 +16,18 @@ var (
 
 type RLE struct {
 	buf []byte
-
-	changes []change
 }
 
-type change struct {
-	set   bool
-	reset bool
-	index uint64
-}
-
-func (c change) valid() bool {
-	return c.reset || c.set
-}
-
-func FromBuf(buf []byte) (*RLE, error) {
-	rle := &RLE{buf: buf}
+func FromBuf(buf []byte) (RLE, error) {
+	rle := RLE{buf: buf}
 
 	if len(buf) > 0 && buf[0]&3 != Version {
-		return nil, xerrors.Errorf("could not create RLE+ for a buffer: %w", ErrWrongVersion)
+		return RLE{}, xerrors.Errorf("could not create RLE+ for a buffer: %w", ErrWrongVersion)
+	}
+
+	_, err := rle.Count()
+	if err != nil {
+		return RLE{}, err
 	}
 
 	return rle, nil
@@ -45,7 +38,26 @@ func (rle *RLE) RunIterator() (RunIterator, error) {
 	return source, err
 }
 
+func (rle *RLE) Count() (uint64, error) {
+	it, err := rle.RunIterator()
+	if err != nil {
+		return 0, err
+	}
+	return Count(it)
+}
+
 /*
+
+type change struct {
+	set   bool
+	reset bool
+	index uint64
+}
+func (c change) valid() bool {
+	return c.reset || c.set
+}
+
+func (rle *RLE) RunIterator() (RunIterator, error) {
 	if err != nil {
 		return nil, err
 	}

lib/rlepluslazy/runs.go

@@ -1,5 +1,11 @@
 package rlepluslazy
 
+import (
+	"math"
+
+	"golang.org/x/xerrors"
+)
+
 func Sum(a, b RunIterator) (RunIterator, error) {
 	it := addIt{a: a, b: b}
 	it.prep()
@@ -94,3 +100,21 @@ func (it *addIt) NextRun() (Run, error) {
 	next := it.next
 	return next, it.prep()
 }
+
+func Count(ri RunIterator) (uint64, error) {
+	var count uint64
+
+	for ri.HasNext() {
+		r, err := ri.NextRun()
+		if err != nil {
+			return 0, err
+		}
+		if r.Val {
+			if math.MaxUint64-r.Len > count {
+				return 0, xerrors.New("RLE+ overflows")
+			}
+			count += r.Len
+		}
+	}
+	return count, nil
+}

lib/rlepluslazy/runs_test.go

@@ -76,8 +76,8 @@ func TestSumRandom(t *testing.T) {
 	N := 100
 
 	for i := 0; i < N; i++ {
-		abits := randomBits(1000, 2000)
-		bbits := randomBits(1000, 2000)
+		abits := randomBits(1000, 1500)
+		bbits := randomBits(1000, 1500)
 		sumbits := sum(abits, bbits)
 
 		a, err := RunsFromSlice(abits)