Routing: Reduce peak memory usage (#5488)

https://github.com/XTLS/Xray-core/pull/5488#issuecomment-3711430369

For https://github.com/XTLS/Xray-core/issues/4422

app/router/condition.go

@@ -307,6 +307,48 @@ func (m *AttributeMatcher) Apply(ctx routing.Context) bool {
 	return m.Match(attributes)
 }
 
+// Geo attribute
+type GeoAttributeMatcher interface {
+	Match(*Domain) bool
+}
+
+type GeoBooleanMatcher string
+
+func (m GeoBooleanMatcher) Match(domain *Domain) bool {
+	for _, attr := range domain.Attribute {
+		if attr.Key == string(m) {
+			return true
+		}
+	}
+	return false
+}
+
+type GeoAttributeList struct {
+	Matcher []GeoAttributeMatcher
+}
+
+func (al *GeoAttributeList) Match(domain *Domain) bool {
+	for _, matcher := range al.Matcher {
+		if !matcher.Match(domain) {
+			return false
+		}
+	}
+	return true
+}
+
+func (al *GeoAttributeList) IsEmpty() bool {
+	return len(al.Matcher) == 0
+}
+
+func ParseAttrs(attrs []string) *GeoAttributeList {
+	al := new(GeoAttributeList)
+	for _, attr := range attrs {
+		lc := strings.ToLower(attr)
+		al.Matcher = append(al.Matcher, GeoBooleanMatcher(lc))
+	}
+	return al
+}
+
 type ProcessNameMatcher struct {
 	names []string
 }
@@ -343,4 +385,4 @@ func (m *ProcessNameMatcher) Apply(ctx routing.Context) bool {
 		}
 	}
 	return false
-}
+}