Fix outbound start sequence

box_outbound.go

@@ -0,0 +1,76 @@
+package box
+
+import (
+	"strings"
+
+	"github.com/sagernet/sing-box/adapter"
+	"github.com/sagernet/sing/common"
+	E "github.com/sagernet/sing/common/exceptions"
+	F "github.com/sagernet/sing/common/format"
+)
+
+func (s *Box) startOutbounds() error {
+	outboundTags := make(map[adapter.Outbound]string)
+	outbounds := make(map[string]adapter.Outbound)
+	for i, outboundToStart := range s.outbounds {
+		var outboundTag string
+		if outboundToStart.Tag() == "" {
+			outboundTag = F.ToString(i)
+		} else {
+			outboundTag = outboundToStart.Tag()
+		}
+		outboundTags[outboundToStart] = outboundTag
+		outbounds[outboundTag] = outboundToStart
+	}
+	started := make(map[string]bool)
+	for {
+		canContinue := false
+	startOne:
+		for _, outboundToStart := range s.outbounds {
+			outboundTag := outboundTags[outboundToStart]
+			if started[outboundTag] {
+				continue
+			}
+			dependencies := outboundToStart.Dependencies()
+			for _, dependency := range dependencies {
+				if !started[dependency] {
+					continue startOne
+				}
+			}
+			started[outboundTag] = true
+			canContinue = true
+			if starter, isStarter := outboundToStart.(common.Starter); isStarter {
+				s.logger.Trace("initializing outbound/", outboundToStart.Type(), "[", outboundTag, "]")
+				err := starter.Start()
+				if err != nil {
+					return E.Cause(err, "initialize outbound/", outboundToStart.Type(), "[", outboundTag, "]")
+				}
+			}
+		}
+		if len(started) == len(s.outbounds) {
+			break
+		}
+		if canContinue {
+			continue
+		}
+		currentOutbound := common.Find(s.outbounds, func(it adapter.Outbound) bool {
+			return !started[outboundTags[it]]
+		})
+		var lintOutbound func(oTree []string, oCurrent adapter.Outbound) error
+		lintOutbound = func(oTree []string, oCurrent adapter.Outbound) error {
+			problemOutboundTag := common.Find(oCurrent.Dependencies(), func(it string) bool {
+				return !started[it]
+			})
+			if common.Contains(oTree, problemOutboundTag) {
+				return E.New("circular outbound dependency: ", strings.Join(oTree, " -> "), " -> ", problemOutboundTag)
+			}
+			problemOutbound := outbounds[problemOutboundTag]
+			if problemOutbound == nil {
+				return E.New("dependency[", problemOutbound, "] not found for outbound[", outboundTags[oCurrent], "]")
+			}
+			return lintOutbound(append(oTree, problemOutboundTag), problemOutbound)
+		}
+		return lintOutbound([]string{outboundTags[currentOutbound]}, currentOutbound)
+	}
+	return nil
+}