Merge branch 'dev' of https://github.com/Dreamacro/clash into Alpha

dns/util.go

@@ -3,6 +3,7 @@ package dns
 import (
 	"context"
 	"crypto/tls"
+	"errors"
 	"fmt"
 	"net"
 	"net/netip"
@@ -11,7 +12,9 @@ import (
 
 	"github.com/Dreamacro/clash/common/cache"
 	"github.com/Dreamacro/clash/common/nnip"
+	"github.com/Dreamacro/clash/common/picker"
 	"github.com/Dreamacro/clash/component/dialer"
+	"github.com/Dreamacro/clash/component/resolver"
 	C "github.com/Dreamacro/clash/constant"
 	"github.com/Dreamacro/clash/log"
 	"github.com/Dreamacro/clash/tunnel"
@@ -71,8 +74,8 @@ func transform(servers []NameServer, resolver *Resolver) []dnsClient {
 		case "quic":
 			if doq, err := newDoQ(resolver, s.Addr, s.ProxyAdapter); err == nil {
 				ret = append(ret, doq)
-			}else{
-				log.Fatalln("DoQ format error: %v",err)
+			} else {
+				log.Fatalln("DoQ format error: %v", err)
 			}
 			continue
 		}
@@ -208,3 +211,31 @@ func dialContextExtra(ctx context.Context, adapterName string, network string, d
 
 	return adapter.DialContext(ctx, metadata, opts...)
 }
+
+func batchExchange(ctx context.Context, clients []dnsClient, m *D.Msg) (msg *D.Msg, err error) {
+	fast, ctx := picker.WithTimeout[*D.Msg](ctx, resolver.DefaultDNSTimeout)
+	for _, client := range clients {
+		r := client
+		fast.Go(func() (*D.Msg, error) {
+			m, err := r.ExchangeContext(ctx, m)
+			if err != nil {
+				return nil, err
+			} else if m.Rcode == D.RcodeServerFailure || m.Rcode == D.RcodeRefused {
+				return nil, errors.New("server failure")
+			}
+			return m, nil
+		})
+	}
+
+	elm := fast.Wait()
+	if elm == nil {
+		err := errors.New("all DNS requests failed")
+		if fErr := fast.Error(); fErr != nil {
+			err = fmt.Errorf("%w, first error: %s", err, fErr.Error())
+		}
+		return nil, err
+	}
+
+	msg = elm
+	return
+}