Add serialize support for domain matcher

common/domain/matcher.go

@@ -1,8 +1,12 @@
 package domain
 
 import (
+	"encoding/binary"
+	"io"
 	"sort"
 	"unicode/utf8"
+
+	"github.com/sagernet/sing/common/rw"
 )
 
 type Matcher struct {
@@ -27,15 +31,87 @@ func NewMatcher(domains []string, domainSuffix []string) *Matcher {
 		domainList = append(domainList, reverseDomain(domain))
 	}
 	sort.Strings(domainList)
-	return &Matcher{
-		newSuccinctSet(domainList),
+	return &Matcher{newSuccinctSet(domainList)}
+}
+
+func ReadMatcher(reader io.Reader) (*Matcher, error) {
+	var version uint8
+	err := binary.Read(reader, binary.BigEndian, &version)
+	if err != nil {
+		return nil, err
 	}
+	leavesLength, err := rw.ReadUVariant(reader)
+	if err != nil {
+		return nil, err
+	}
+	leaves := make([]uint64, leavesLength)
+	err = binary.Read(reader, binary.BigEndian, leaves)
+	if err != nil {
+		return nil, err
+	}
+	labelBitmapLength, err := rw.ReadUVariant(reader)
+	if err != nil {
+		return nil, err
+	}
+	labelBitmap := make([]uint64, labelBitmapLength)
+	err = binary.Read(reader, binary.BigEndian, labelBitmap)
+	if err != nil {
+		return nil, err
+	}
+	labelsLength, err := rw.ReadUVariant(reader)
+	if err != nil {
+		return nil, err
+	}
+	labels := make([]byte, labelsLength)
+	_, err = io.ReadFull(reader, labels)
+	if err != nil {
+		return nil, err
+	}
+	set := &succinctSet{
+		leaves:      leaves,
+		labelBitmap: labelBitmap,
+		labels:      labels,
+	}
+	set.init()
+	return &Matcher{set}, nil
 }
 
 func (m *Matcher) Match(domain string) bool {
 	return m.set.Has(reverseDomain(domain))
 }
 
+func (m *Matcher) Write(writer io.Writer) error {
+	err := binary.Write(writer, binary.BigEndian, byte(1))
+	if err != nil {
+		return err
+	}
+	err = rw.WriteUVariant(writer, uint64(len(m.set.leaves)))
+	if err != nil {
+		return err
+	}
+	err = binary.Write(writer, binary.BigEndian, m.set.leaves)
+	if err != nil {
+		return err
+	}
+	err = rw.WriteUVariant(writer, uint64(len(m.set.labelBitmap)))
+	if err != nil {
+		return err
+	}
+	err = binary.Write(writer, binary.BigEndian, m.set.labelBitmap)
+	if err != nil {
+		return err
+	}
+	err = rw.WriteUVariant(writer, uint64(len(m.set.labels)))
+	if err != nil {
+		return err
+	}
+	_, err = writer.Write(m.set.labels)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
 func reverseDomain(domain string) string {
 	l := len(domain)
 	b := make([]byte, l)