add more options for grpc

limiter/conn/limiter.go

@@ -1,6 +1,7 @@
 package conn
 
 import (
+	"sort"
 	"sync/atomic"
 
 	limiter "github.com/go-gost/core/limiter/conn"
@@ -28,3 +29,39 @@ func (l *llimiter) Allow(n int) bool {
 	}
 	return true
 }
+
+type limiterGroup struct {
+	limiters []limiter.Limiter
+}
+
+func newLimiterGroup(limiters ...limiter.Limiter) *limiterGroup {
+	sort.Slice(limiters, func(i, j int) bool {
+		return limiters[i].Limit() < limiters[j].Limit()
+	})
+	return &limiterGroup{limiters: limiters}
+}
+
+func (l *limiterGroup) Allow(n int) (b bool) {
+	var i int
+
+	for i = range l.limiters {
+		if b = l.limiters[i].Allow(n); !b {
+			break
+		}
+	}
+	if !b && i > 0 && n > 0 {
+		for i := range l.limiters[:i] {
+			l.limiters[i].Allow(-n)
+		}
+	}
+
+	return
+}
+
+func (l *limiterGroup) Limit() int {
+	if len(l.limiters) == 0 {
+		return 0
+	}
+
+	return l.limiters[0].Limit()
+}