Pull request: all: opt log levels more

Updates #3929.

Squashed commit of the following:

commit 0d4aadeff1c4de1440795faf83eb072c46392ff3
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Tue Dec 28 16:34:44 2021 +0300

    all: opt log levels more

go.mod

@@ -3,7 +3,7 @@ module github.com/AdguardTeam/AdGuardHome
 go 1.17
 
 require (
-	github.com/AdguardTeam/dnsproxy v0.40.1
+	github.com/AdguardTeam/dnsproxy v0.40.2
 	github.com/AdguardTeam/golibs v0.10.3
 	github.com/AdguardTeam/urlfilter v0.15.1
 	github.com/NYTimes/gziphandler v1.1.1

go.sum

@@ -7,8 +7,8 @@ dmitri.shuralyov.com/html/belt v0.0.0-20180602232347-f7d459c86be0/go.mod h1:JLBr
 dmitri.shuralyov.com/service/change v0.0.0-20181023043359-a85b471d5412/go.mod h1:a1inKt/atXimZ4Mv927x+r7UpyzRUf4emIoiiSC2TN4=
 dmitri.shuralyov.com/state v0.0.0-20180228185332-28bcc343414c/go.mod h1:0PRwlb0D6DFvNNtx+9ybjezNCa8XF0xaYcETyp6rHWU=
 git.apache.org/thrift.git v0.0.0-20180902110319-2566ecd5d999/go.mod h1:fPE2ZNJGynbRyZ4dJvy6G277gSllfV2HJqblrnkyeyg=
-github.com/AdguardTeam/dnsproxy v0.40.1 h1:lYNi7VeCBhmdyf5xEUxfj84ikgiz5cjzocL9moiIRhk=
+github.com/AdguardTeam/dnsproxy v0.40.2 h1:GG4StH+d4rB7YW3d20sdQjJG8URUeaIQicnEAsYJY7w=
-github.com/AdguardTeam/dnsproxy v0.40.1/go.mod h1:PZ9l22h3Er+5mxFQB7oHZMTvx+aa9R6LbzA/ikXQlS0=
+github.com/AdguardTeam/dnsproxy v0.40.2/go.mod h1:PZ9l22h3Er+5mxFQB7oHZMTvx+aa9R6LbzA/ikXQlS0=
 github.com/AdguardTeam/golibs v0.4.0/go.mod h1:skKsDKIBB7kkFflLJBpfGX+G8QFTx0WKUzB6TIgtUj4=
 github.com/AdguardTeam/golibs v0.4.2/go.mod h1:skKsDKIBB7kkFflLJBpfGX+G8QFTx0WKUzB6TIgtUj4=
 github.com/AdguardTeam/golibs v0.9.2/go.mod h1:fCAMwPBJ8S7YMYbTWvYS+eeTLblP5E04IDtNAo7y7IY=

internal/dhcpd/v4.go

@@ -1056,8 +1056,6 @@ func (s *v4Server) Start() (err error) {
 	go func() {
 		if serr := s.srv.Serve(); errors.Is(serr, net.ErrClosed) {
 			log.Info("dhcpv4: server is closed")
-
-			return
 		} else if serr != nil {
 			log.Error("dhcpv4: srv.Serve: %s", serr)
 		}

internal/dhcpd/v6.go

@@ -662,8 +662,11 @@ func (s *v6Server) Start() (err error) {
 	}
 
 	go func() {
-		err = s.srv.Serve()
+		if serr := s.srv.Serve(); errors.Is(serr, net.ErrClosed) {
-		log.Error("dhcpv6: srv.Serve: %s", err)
+			log.Info("dhcpv6: server is closed")
+		} else if serr != nil {
+			log.Error("dhcpv6: srv.Serve: %s", serr)
+		}
 	}()
 
 	return nil

internal/home/web.go

@@ -10,6 +10,7 @@ import (
 	"time"
 
 	"github.com/AdguardTeam/AdGuardHome/internal/aghnet"
+	"github.com/AdguardTeam/golibs/errors"
 	"github.com/AdguardTeam/golibs/log"
 	"github.com/AdguardTeam/golibs/netutil"
 	"github.com/NYTimes/gziphandler"
@@ -175,35 +176,48 @@ func (web *Web) Start() {
 			WriteTimeout:      web.conf.WriteTimeout,
 		}
 		go func() {
+			defer log.OnPanic("web: plain")
+
 			errs <- web.httpServer.ListenAndServe()
 		}()
 
-		if web.conf.BetaBindPort != 0 {
+		web.startBetaServer(hostStr)
-			web.httpServerBeta = &http.Server{
-				ErrorLog:          log.StdLog("web: plain", log.DEBUG),
-				Addr:              netutil.JoinHostPort(hostStr, web.conf.BetaBindPort),
-				Handler:           withMiddlewares(Context.mux, limitRequestBody, web.wrapIndexBeta),
-				ReadTimeout:       web.conf.ReadTimeout,
-				ReadHeaderTimeout: web.conf.ReadHeaderTimeout,
-				WriteTimeout:      web.conf.WriteTimeout,
-			}
-			go func() {
-				betaErr := web.httpServerBeta.ListenAndServe()
-				if betaErr != nil {
-					log.Error("starting beta http server: %s", betaErr)
-				}
-			}()
-		}
 
 		err := <-errs
-		if err != http.ErrServerClosed {
+		if !errors.Is(err, http.ErrServerClosed) {
 			cleanupAlways()
 			log.Fatal(err)
 		}
-		// We use ErrServerClosed as a sign that we need to rebind on new address, so go back to the start of the loop
+
+		// We use ErrServerClosed as a sign that we need to rebind on a new
+		// address, so go back to the start of the loop.
 	}
 }
 
+// startBetaServer starts the beta HTTP server if necessary.
+func (web *Web) startBetaServer(hostStr string) {
+	if web.conf.BetaBindPort == 0 {
+		return
+	}
+
+	web.httpServerBeta = &http.Server{
+		ErrorLog:          log.StdLog("web: plain: beta", log.DEBUG),
+		Addr:              netutil.JoinHostPort(hostStr, web.conf.BetaBindPort),
+		Handler:           withMiddlewares(Context.mux, limitRequestBody, web.wrapIndexBeta),
+		ReadTimeout:       web.conf.ReadTimeout,
+		ReadHeaderTimeout: web.conf.ReadHeaderTimeout,
+		WriteTimeout:      web.conf.WriteTimeout,
+	}
+	go func() {
+		defer log.OnPanic("web: plain: beta")
+
+		betaErr := web.httpServerBeta.ListenAndServe()
+		if betaErr != nil && !errors.Is(betaErr, http.ErrServerClosed) {
+			log.Error("starting beta http server: %s", betaErr)
+		}
+	}()
+}
+
 // Close gracefully shuts down the HTTP servers.
 func (web *Web) Close(ctx context.Context) {
 	log.Info("stopping http server...")