Geodata: Reduce memory usage again (#5975)

https://github.com/XTLS/Xray-core/pull/5975#issuecomment-4274779560

common/geodata/strmatcher/matchers.go

@@ -288,3 +288,65 @@ func CompositeMatchesReverse(matches [][]uint32) []uint32 {
 		return result
 	}
 }
+
+// MatcherSetForAll is an interface indicating a MatcherSet could accept all types of matchers.
+type MatcherSetForAll interface {
+	AddMatcher(matcher Matcher)
+}
+
+// MatcherSetForFull is an interface indicating a MatcherSet could accept FullMatchers.
+type MatcherSetForFull interface {
+	AddFullMatcher(matcher FullMatcher)
+}
+
+// MatcherSetForDomain is an interface indicating a MatcherSet could accept DomainMatchers.
+type MatcherSetForDomain interface {
+	AddDomainMatcher(matcher DomainMatcher)
+}
+
+// MatcherSetForSubstr is an interface indicating a MatcherSet could accept SubstrMatchers.
+type MatcherSetForSubstr interface {
+	AddSubstrMatcher(matcher SubstrMatcher)
+}
+
+// MatcherSetForRegex is an interface indicating a MatcherSet could accept RegexMatchers.
+type MatcherSetForRegex interface {
+	AddRegexMatcher(matcher *RegexMatcher)
+}
+
+// AddMatcherToSet is a helper function to try to add a Matcher to any kind of MatcherSet.
+// It returns error if the MatcherSet does not accept the provided Matcher's type.
+// This function is provided to help writing code to test a MatcherSet.
+func AddMatcherToSet(s MatcherSet, matcher Matcher) error {
+	if s, ok := s.(IndexMatcher); ok {
+		s.Add(matcher)
+		return nil
+	}
+	if s, ok := s.(MatcherSetForAll); ok {
+		s.AddMatcher(matcher)
+		return nil
+	}
+	switch matcher := matcher.(type) {
+	case FullMatcher:
+		if s, ok := s.(MatcherSetForFull); ok {
+			s.AddFullMatcher(matcher)
+			return nil
+		}
+	case DomainMatcher:
+		if s, ok := s.(MatcherSetForDomain); ok {
+			s.AddDomainMatcher(matcher)
+			return nil
+		}
+	case SubstrMatcher:
+		if s, ok := s.(MatcherSetForSubstr); ok {
+			s.AddSubstrMatcher(matcher)
+			return nil
+		}
+	case *RegexMatcher:
+		if s, ok := s.(MatcherSetForRegex); ok {
+			s.AddRegexMatcher(matcher)
+			return nil
+		}
+	}
+	return errors.New("cannot add matcher to matcher set")
+}