loopd: fix data races of logger

loopd/config.go

@@ -423,7 +423,7 @@ func getTLSConfig(cfg *Config) (*tls.Config, *credentials.TransportCredentials,
 	// If the certificate expired or it was outdated, delete it and the TLS
 	// key and generate a new pair.
 	if time.Now().After(parsedCert.NotAfter) {
-		log.Info("TLS certificate is expired or outdated, " +
+		infof("TLS certificate is expired or outdated, " +
 			"removing old file then generating a new one")
 
 		err := os.Remove(cfg.TLSCertPath)
@@ -464,7 +464,7 @@ func loadCertWithCreate(cfg *Config) (tls.Certificate, *x509.Certificate,
 	if !lnrpc.FileExists(cfg.TLSCertPath) &&
 		!lnrpc.FileExists(cfg.TLSKeyPath) {
 
-		log.Infof("Generating TLS certificates...")
+		infof("Generating TLS certificates...")
 		certBytes, keyBytes, err := cert.GenCertPair(
 			defaultSelfSignedOrganization, cfg.TLSExtraIPs,
 			cfg.TLSExtraDomains, cfg.TLSDisableAutofill,
@@ -481,7 +481,7 @@ func loadCertWithCreate(cfg *Config) (tls.Certificate, *x509.Certificate,
 			return tls.Certificate{}, nil, err
 		}
 
-		log.Infof("Done generating TLS certificates")
+		infof("Done generating TLS certificates")
 	}
 
 	return cert.LoadCert(cfg.TLSCertPath, cfg.TLSKeyPath)

loopd/daemon.go

@@ -169,11 +169,11 @@ func (d *Daemon) Start() error {
 	// anything goes wrong now, we need to cleanly shut down again.
 	startErr := d.startWebServers()
 	if startErr != nil {
-		log.Errorf("Error while starting daemon: %v", err)
+		errorf("Error while starting daemon: %v", err)
 		d.Stop()
 		stopErr := <-d.ErrChan
 		if stopErr != nil {
-			log.Errorf("Error while stopping daemon: %v", stopErr)
+			errorf("Error while stopping daemon: %v", stopErr)
 		}
 		return startErr
 	}
@@ -253,7 +253,7 @@ func (d *Daemon) startWebServers() error {
 	d.registerDebugServer()
 
 	// Next, start the gRPC server listening for HTTP/2 connections.
-	log.Infof("Starting gRPC listener")
+	infof("Starting gRPC listener")
 	serverTLSCfg, restClientCreds, err := getTLSConfig(d.cfg)
 	if err != nil {
 		return fmt.Errorf("could not create gRPC server options: %v",
@@ -322,7 +322,7 @@ func (d *Daemon) startWebServers() error {
 
 	// A nil listener indicates REST is disabled.
 	if d.restListener != nil {
-		log.Infof("Starting REST proxy listener")
+		infof("Starting REST proxy listener")
 
 		d.restServer = &http.Server{
 			Handler:           restHandler,
@@ -333,7 +333,7 @@ func (d *Daemon) startWebServers() error {
 		go func() {
 			defer d.wg.Done()
 
-			log.Infof("REST proxy listening on %s",
+			infof("REST proxy listening on %s",
 				d.restListener.Addr())
 			err := d.restServer.Serve(d.restListener)
 			// ErrServerClosed is always returned when the proxy is
@@ -347,7 +347,7 @@ func (d *Daemon) startWebServers() error {
 			}
 		}()
 	} else {
-		log.Infof("REST proxy disabled")
+		infof("REST proxy disabled")
 	}
 
 	// Start the grpc server.
@@ -355,7 +355,7 @@ func (d *Daemon) startWebServers() error {
 	go func() {
 		defer d.wg.Done()
 
-		log.Infof("RPC server listening on %s", d.grpcListener.Addr())
+		infof("RPC server listening on %s", d.grpcListener.Addr())
 		err = d.grpcServer.Serve(d.grpcListener)
 		if err != nil && !errors.Is(err, grpc.ErrServerStopped) {
 			// Notify the main error handler goroutine that
@@ -378,7 +378,7 @@ func (d *Daemon) initialize(withMacaroonService bool) error {
 		loopdb.EnableExperimentalProtocol()
 	}
 
-	log.Infof("Protocol version: %v", loopdb.CurrentProtocolVersion())
+	infof("Protocol version: %v", loopdb.CurrentProtocolVersion())
 
 	// If no swap server is specified, use the default addresses for mainnet
 	// and testnet.
@@ -404,18 +404,18 @@ func (d *Daemon) initialize(withMacaroonService bool) error {
 	// on main context cancel. So we create it early and pass it down.
 	d.mainCtx, d.mainCtxCancel = context.WithCancel(context.Background())
 
-	log.Infof("Swap server address: %v", d.cfg.Server.Host)
+	infof("Swap server address: %v", d.cfg.Server.Host)
 
 	// Check if we need to migrate the database.
 	if needSqlMigration(d.cfg) {
-		log.Infof("Boltdb found, running migration")
+		infof("Boltdb found, running migration")
 
 		err := migrateBoltdb(d.mainCtx, d.cfg)
 		if err != nil {
 			return fmt.Errorf("unable to migrate boltdb: %v", err)
 		}
 
-		log.Infof("Successfully migrated boltdb")
+		infof("Successfully migrated boltdb")
 	}
 
 	// Now that we know where the database will live, we'll go ahead and
@@ -436,7 +436,7 @@ func (d *Daemon) initialize(withMacaroonService bool) error {
 		swapDb,
 	)
 	if err != nil {
-		log.Errorf("Cost migration failed: %v", err)
+		errorf("Cost migration failed: %v", err)
 
 		return err
 	}
@@ -460,7 +460,7 @@ func (d *Daemon) initialize(withMacaroonService bool) error {
 				d.lnd.NodePubkey)
 		}
 
-		log.Infof("Using asset client with version %v", getInfo.Version)
+		infof("Using asset client with version %v", getInfo.Version)
 	}
 
 	// Create an instance of the loop client library.
@@ -507,7 +507,7 @@ func (d *Daemon) initialize(withMacaroonService bool) error {
 	cleanupMacaroonStore := func() {
 		err := db.Close()
 		if err != nil {
-			log.Errorf("Error closing macaroon store: %v", err)
+			errorf("Error closing macaroon store: %v", err)
 		}
 	}
 
@@ -555,11 +555,11 @@ func (d *Daemon) initialize(withMacaroonService bool) error {
 	go func() {
 		defer d.wg.Done()
 
-		log.Info("Starting notification manager")
+		infof("Starting notification manager")
 		err := notificationManager.Run(d.mainCtx)
 		if err != nil {
 			d.internalErrChan <- err
-			log.Errorf("Notification manager stopped: %v", err)
+			errorf("Notification manager stopped: %v", err)
 		}
 	}()
 
@@ -711,7 +711,7 @@ func (d *Daemon) initialize(withMacaroonService bool) error {
 		// started yet, so if we clean that up now, nothing else needs
 		// to be shut down at this point.
 		if err := d.macaroonService.Stop(); err != nil {
-			log.Errorf("Error shutting down macaroon service: %v",
+			errorf("Error shutting down macaroon service: %v",
 				err)
 		}
 		cleanupMacaroonStore()
@@ -728,7 +728,7 @@ func (d *Daemon) initialize(withMacaroonService bool) error {
 	go func() {
 		defer d.wg.Done()
 
-		log.Infof("Starting swap client")
+		infof("Starting swap client")
 		err := d.impl.Run(d.mainCtx, d.statusChan)
 		if err != nil {
 			// Notify the main error handler goroutine that
@@ -737,7 +737,7 @@ func (d *Daemon) initialize(withMacaroonService bool) error {
 			// channel is sufficiently buffered.
 			d.internalErrChan <- err
 		}
-		log.Infof("Swap client stopped")
+		infof("Swap client stopped")
 	}()
 
 	// Start a goroutine that broadcasts swap updates to clients.
@@ -745,7 +745,7 @@ func (d *Daemon) initialize(withMacaroonService bool) error {
 	go func() {
 		defer d.wg.Done()
 
-		log.Infof("Waiting for updates")
+		infof("Waiting for updates")
 		d.processStatusUpdates(d.mainCtx)
 	}()
 
@@ -753,13 +753,13 @@ func (d *Daemon) initialize(withMacaroonService bool) error {
 	go func() {
 		defer d.wg.Done()
 
-		log.Info("Starting liquidity manager")
+		infof("Starting liquidity manager")
 		err := d.liquidityMgr.Run(d.mainCtx)
 		if err != nil && !errors.Is(err, context.Canceled) {
 			d.internalErrChan <- err
 		}
 
-		log.Info("Liquidity manager stopped")
+		infof("Liquidity manager stopped")
 	}()
 
 	// Start the reservation manager.
@@ -777,8 +777,8 @@ func (d *Daemon) initialize(withMacaroonService bool) error {
 				return
 			}
 
-			log.Info("Starting reservation manager")
+			infof("Starting reservation manager")
-			defer log.Info("Reservation manager stopped")
+			defer infof("Reservation manager stopped")
 
 			err = d.reservationManager.Run(
 				d.mainCtx, int32(getInfo.BlockHeight), initChan,
@@ -815,8 +815,8 @@ func (d *Daemon) initialize(withMacaroonService bool) error {
 				return
 			}
 
-			log.Info("Starting instantout manager")
+			infof("Starting instantout manager")
-			defer log.Info("Instantout manager stopped")
+			defer infof("Instantout manager stopped")
 
 			err = d.instantOutManager.Run(
 				d.mainCtx, initChan, int32(getInfo.BlockHeight),
@@ -846,12 +846,12 @@ func (d *Daemon) initialize(withMacaroonService bool) error {
 		go func() {
 			defer d.wg.Done()
 
-			log.Info("Starting static address manager...")
+			infof("Starting static address manager...")
 			err = staticAddressManager.Run(d.mainCtx)
 			if err != nil && !errors.Is(context.Canceled, err) {
 				d.internalErrChan <- err
 			}
-			log.Info("Static address manager stopped")
+			infof("Static address manager stopped")
 		}()
 	}
 
@@ -869,12 +869,12 @@ func (d *Daemon) initialize(withMacaroonService bool) error {
 				return
 			}
 
-			log.Info("Starting static address deposit manager...")
+			infof("Starting static address deposit manager...")
 			err = depositManager.Run(d.mainCtx, info.BlockHeight)
 			if err != nil && !errors.Is(context.Canceled, err) {
 				d.internalErrChan <- err
 			}
-			log.Info("Static address deposit manager stopped")
+			infof("Static address deposit manager stopped")
 		}()
 		depositManager.WaitInitComplete()
 	}
@@ -893,13 +893,13 @@ func (d *Daemon) initialize(withMacaroonService bool) error {
 				return
 			}
 
-			log.Info("Starting static address deposit withdrawal " +
+			infof("Starting static address deposit withdrawal " +
 				"manager...")
 			err = withdrawalManager.Run(d.mainCtx, info.BlockHeight)
 			if err != nil && !errors.Is(context.Canceled, err) {
 				d.internalErrChan <- err
 			}
-			log.Info("Static address deposit withdrawal manager " +
+			infof("Static address deposit withdrawal manager " +
 				"stopped")
 		}()
 		withdrawalManager.WaitInitComplete()
@@ -920,14 +920,14 @@ func (d *Daemon) initialize(withMacaroonService bool) error {
 				return
 			}
 
-			log.Info("Starting static address loop-in manager...")
+			infof("Starting static address loop-in manager...")
 			err = staticLoopInManager.Run(
 				d.mainCtx, info.BlockHeight,
 			)
 			if err != nil && !errors.Is(context.Canceled, err) {
 				d.internalErrChan <- err
 			}
-			log.Info("Starting static address loop-in manager " +
+			infof("Starting static address loop-in manager " +
 				"stopped")
 		}()
 		staticLoopInManager.WaitInitComplete()
@@ -948,7 +948,7 @@ func (d *Daemon) initialize(withMacaroonService bool) error {
 		// signal the caller that we're done.
 		select {
 		case runtimeErr = <-d.internalErrChan:
-			log.Errorf("Runtime error in daemon, shutting down: "+
+			errorf("Runtime error in daemon, shutting down: "+
 				"%v", runtimeErr)
 
 		case <-d.quit:
@@ -958,7 +958,7 @@ func (d *Daemon) initialize(withMacaroonService bool) error {
 		// otherwise a caller might exit the process too early.
 		d.stop()
 		cleanupMacaroonStore()
-		log.Info("Daemon exited")
+		infof("Daemon exited")
 
 		// The caller expects exactly one message. So we send the error
 		// even if it's nil because we cleanly shut down.
@@ -987,17 +987,17 @@ func (d *Daemon) stop() {
 
 	// As there is no swap activity anymore, we can forcefully shut down the
 	// gRPC and HTTP servers now.
-	log.Infof("Stopping gRPC server")
+	infof("Stopping gRPC server")
 	if d.grpcServer != nil {
 		d.grpcServer.Stop()
 	}
-	log.Infof("Stopping REST server")
+	infof("Stopping REST server")
 	if d.restServer != nil {
 		// Don't return the error here, we first want to give everything
 		// else a chance to shut down cleanly.
 		err := d.restServer.Close()
 		if err != nil {
-			log.Errorf("Error stopping REST server: %v", err)
+			errorf("Error stopping REST server: %v", err)
 		}
 	}
 	if d.restCtxCancel != nil {
@@ -1007,7 +1007,7 @@ func (d *Daemon) stop() {
 	if d.macaroonService != nil {
 		err := d.macaroonService.Stop()
 		if err != nil {
-			log.Errorf("Error stopping macaroon service: %v", err)
+			errorf("Error stopping macaroon service: %v", err)
 		}
 	}
 

loopd/log.go

@@ -1,6 +1,8 @@
 package loopd
 
 import (
+	"sync/atomic"
+
 	"github.com/btcsuite/btclog/v2"
 	"github.com/lightninglabs/aperture/l402"
 	"github.com/lightninglabs/lndclient"
@@ -22,18 +24,50 @@ import (
 const Subsystem = "LOOPD"
 
 var (
-	log         btclog.Logger
+	log_        atomic.Pointer[btclog.Logger]
 	interceptor signal.Interceptor
 )
 
+// log returns active logger.
+func log() btclog.Logger {
+	return *log_.Load()
+}
+
+// setLogger uses a specified Logger to output package logging info.
+func setLogger(logger btclog.Logger) {
+	log_.Store(&logger)
+}
+
+// tracef logs a message with level TRACE.
+func tracef(format string, params ...interface{}) {
+	log().Tracef(format, params...)
+}
+
+// infof logs a message with level INFO.
+func infof(format string, params ...interface{}) {
+	log().Infof(format, params...)
+}
+
+// warnf logs a message with level WARN.
+func warnf(format string, params ...interface{}) {
+	log().Warnf(format, params...)
+}
+
+// errorf logs a message with level ERROR.
+func errorf(format string, params ...interface{}) {
+	log().Errorf(format, params...)
+}
+
 // SetupLoggers initializes all package-global logger variables.
 func SetupLoggers(root *build.SubLoggerManager, intercept signal.Interceptor) {
 	genLogger := genSubLogger(root, intercept)
 
-	log = build.NewSubLogger(Subsystem, genLogger)
+	logger := build.NewSubLogger(Subsystem, genLogger)
+	setLogger(logger)
+
 	interceptor = intercept
 
-	lnd.SetSubLogger(root, Subsystem, log)
+	lnd.SetSubLogger(root, Subsystem, logger)
 	lnd.AddSubLogger(root, "LOOP", intercept, loop.UseLogger)
 	lnd.AddSubLogger(root, "SWEEP", intercept, sweepbatcher.UseLogger)
 	lnd.AddSubLogger(root, "LNDC", intercept, lndclient.UseLogger)

loopd/migration.go

@@ -66,7 +66,7 @@ func needSqlMigration(cfg *Config) bool {
 	// any deleted files occasionally (reboot, etc).
 	sqliteDBPath := filepath.Join(cfg.DataDir, "loop_sqlite.db")
 	if lnrpc.FileExists(sqliteDBPath) {
-		log.Infof("Found sqlite db at %v, skipping migration",
+		infof("Found sqlite db at %v, skipping migration",
 			sqliteDBPath)
 
 		return false

loopd/run.go

@@ -222,7 +222,7 @@ func Run(rpcCfg RPCConfig) error {
 	}
 
 	// Print the version before executing either primary directive.
-	log.Infof("Version: %v", loop.Version())
+	infof("Version: %v", loop.Version())
 
 	lisCfg := NewListenerConfig(&config, rpcCfg)
 
@@ -235,7 +235,7 @@ func Run(rpcCfg RPCConfig) error {
 
 		select {
 		case <-interceptor.ShutdownChannel():
-			log.Infof("Received SIGINT (Ctrl+C).")
+			infof("Received SIGINT (Ctrl+C).")
 			daemon.Stop()
 
 			// The above stop will return immediately. But we'll be

loopd/swapclient_server.go

@@ -112,7 +112,7 @@ func (s *swapClientServer) LoopOut(ctx context.Context,
 	in *looprpc.LoopOutRequest) (
 	*looprpc.SwapResponse, error) {
 
-	log.Infof("Loop out request received")
+	infof("Loop out request received")
 
 	// Note that LoopOutRequest.PaymentTimeout is unsigned and therefore
 	// cannot be negative.
@@ -257,7 +257,7 @@ func (s *swapClientServer) LoopOut(ctx context.Context,
 
 	info, err := s.impl.LoopOut(ctx, req)
 	if err != nil {
-		log.Errorf("LoopOut: %v", err)
+		errorf("LoopOut: %v", err)
 		return nil, err
 	}
 
@@ -461,7 +461,7 @@ func (s *swapClientServer) marshallSwap(ctx context.Context,
 func (s *swapClientServer) Monitor(in *looprpc.MonitorRequest,
 	server looprpc.SwapClient_MonitorServer) error {
 
-	log.Infof("Monitor request received")
+	infof("Monitor request received")
 
 	send := func(info loop.SwapInfo) error {
 		rpcSwap, err := s.marshallSwap(server.Context(), &info)
@@ -732,11 +732,11 @@ func (s *swapClientServer) AbandonSwap(ctx context.Context,
 func (s *swapClientServer) LoopOutTerms(ctx context.Context,
 	_ *looprpc.TermsRequest) (*looprpc.OutTermsResponse, error) {
 
-	log.Infof("Loop out terms request received")
+	infof("Loop out terms request received")
 
 	terms, err := s.impl.LoopOutTerms(ctx, defaultLoopdInitiator)
 	if err != nil {
-		log.Errorf("Terms request: %v", err)
+		errorf("Terms request: %v", err)
 		return nil, err
 	}
 
@@ -822,11 +822,11 @@ func (s *swapClientServer) LoopOutQuote(ctx context.Context,
 func (s *swapClientServer) GetLoopInTerms(ctx context.Context,
 	_ *looprpc.TermsRequest) (*looprpc.InTermsResponse, error) {
 
-	log.Infof("Loop in terms request received")
+	infof("Loop in terms request received")
 
 	terms, err := s.impl.LoopInTerms(ctx, defaultLoopdInitiator)
 	if err != nil {
-		log.Errorf("Terms request: %v", err)
+		errorf("Terms request: %v", err)
 		return nil, err
 	}
 
@@ -840,7 +840,7 @@ func (s *swapClientServer) GetLoopInTerms(ctx context.Context,
 func (s *swapClientServer) GetLoopInQuote(ctx context.Context,
 	req *looprpc.QuoteRequest) (*looprpc.InQuoteResponse, error) {
 
-	log.Infof("Loop in quote request received")
+	infof("Loop in quote request received")
 
 	var (
 		numDeposits = uint32(len(req.DepositOutpoints))
@@ -981,7 +981,7 @@ func unmarshallHopHint(rpcHint *swapserverrpc.HopHint) (zpay32.HopHint, error) {
 func (s *swapClientServer) Probe(ctx context.Context,
 	req *looprpc.ProbeRequest) (*looprpc.ProbeResponse, error) {
 
-	log.Infof("Probe request received")
+	infof("Probe request received")
 
 	var lastHop *route.Vertex
 	if req.LastHop != nil {
@@ -1013,7 +1013,7 @@ func (s *swapClientServer) Probe(ctx context.Context,
 func (s *swapClientServer) LoopIn(ctx context.Context,
 	in *looprpc.LoopInRequest) (*looprpc.SwapResponse, error) {
 
-	log.Infof("Loop in request received")
+	infof("Loop in request received")
 
 	htlcConfTarget, err := validateLoopInRequest(
 		in.HtlcConfTarget, in.ExternalHtlc, 0, in.Amt,
@@ -1052,7 +1052,7 @@ func (s *swapClientServer) LoopIn(ctx context.Context,
 	}
 	swapInfo, err := s.impl.LoopIn(ctx, req)
 	if err != nil {
-		log.Errorf("Loop in: %v", err)
+		errorf("Loop in: %v", err)
 		return nil, err
 	}
 
@@ -1079,7 +1079,7 @@ func (s *swapClientServer) LoopIn(ctx context.Context,
 func (s *swapClientServer) GetL402Tokens(ctx context.Context,
 	_ *looprpc.TokensRequest) (*looprpc.TokensResponse, error) {
 
-	log.Infof("Get L402 tokens request received")
+	infof("Get L402 tokens request received")
 
 	tokens, err := s.impl.L402Store.AllTokens()
 	if err != nil {
@@ -1128,7 +1128,7 @@ func (s *swapClientServer) GetL402Tokens(ctx context.Context,
 func (s *swapClientServer) GetLsatTokens(ctx context.Context,
 	req *looprpc.TokensRequest) (*looprpc.TokensResponse, error) {
 
-	log.Warnf("Received deprecated call GetLsatTokens. Please update the " +
+	warnf("Received deprecated call GetLsatTokens. Please update the " +
 		"client software. Calling GetL402Tokens now.")
 
 	return s.GetL402Tokens(ctx, req)
@@ -1754,7 +1754,7 @@ func (s *swapClientServer) StaticAddressLoopIn(ctx context.Context,
 	in *looprpc.StaticAddressLoopInRequest) (
 	*looprpc.StaticAddressLoopInResponse, error) {
 
-	log.Infof("Static loop-in request received")
+	infof("Static loop-in request received")
 
 	routeHints, err := unmarshallRouteHints(in.RouteHints)
 	if err != nil {
@@ -2187,52 +2187,52 @@ func validateLoopOutRequest(ctx context.Context, lnd lndclient.LightningClient,
 func hasBandwidth(channels []lndclient.ChannelInfo, amt btcutil.Amount,
 	maxParts int) (bool, int) {
 
-	log.Tracef("Checking if %v sats can be routed with %v parts over "+
+	tracef("Checking if %v sats can be routed with %v parts over "+
 		"channel set of length %v", amt, maxParts, len(channels))
 
 	localBalances := make([]btcutil.Amount, len(channels))
 	var totalBandwidth btcutil.Amount
 	for i, channel := range channels {
-		log.Tracef("Channel %v: local=%v remote=%v", channel.ChannelID,
+		tracef("Channel %v: local=%v remote=%v", channel.ChannelID,
 			channel.LocalBalance, channel.RemoteBalance)
 
 		localBalances[i] = channel.LocalBalance
 		totalBandwidth += channel.LocalBalance
 	}
 
-	log.Tracef("Total bandwidth: %v", totalBandwidth)
+	tracef("Total bandwidth: %v", totalBandwidth)
 	if totalBandwidth < amt {
 		return false, 0
 	}
 
 	logLocalBalances := func(shard int) {
-		log.Tracef("Local balances for %v shards:", shard)
+		tracef("Local balances for %v shards:", shard)
 		for i, balance := range localBalances {
-			log.Tracef("Channel %v: localBalances[%v]=%v",
+			tracef("Channel %v: localBalances[%v]=%v",
 				channels[i].ChannelID, i, balance)
 		}
 	}
 
 	split := amt
 	for shard := 0; shard <= maxParts; {
-		log.Tracef("Trying to split %v sats into %v parts", amt, shard)
+		tracef("Trying to split %v sats into %v parts", amt, shard)
 
 		paid := false
 		for i := 0; i < len(localBalances); i++ {
 			// TODO(hieblmi): Consider channel reserves because the
 			//      channel can't send its full local balance.
 			if localBalances[i] >= split {
-				log.Tracef("len(shards)=%v: Local channel "+
+				tracef("len(shards)=%v: Local channel "+
 					"balance %v can pay %v sats",
 					shard, localBalances[i], split)
 
 				localBalances[i] -= split
-				log.Tracef("len(shards)=%v: Subtracted "+
+				tracef("len(shards)=%v: Subtracted "+
 					"%v sats from localBalance[%v]=%v",
 					shard, split, i, localBalances[i])
 
 				amt -= split
-				log.Tracef("len(shards)=%v: Remaining total "+
+				tracef("len(shards)=%v: Remaining total "+
 					"amount amt=%v", shard, amt)
 
 				paid = true
@@ -2245,26 +2245,26 @@ func hasBandwidth(channels []lndclient.ChannelInfo, amt btcutil.Amount,
 		logLocalBalances(shard)
 
 		if amt == 0 {
-			log.Tracef("Payment is routable with %v part(s)", shard)
+			tracef("Payment is routable with %v part(s)", shard)
 
 			return true, shard
 		}
 
 		if !paid {
-			log.Tracef("len(shards)=%v: No channel could pay %v "+
+			tracef("len(shards)=%v: No channel could pay %v "+
 				"sats, halving payment to %v and trying again",
 				split/2)
 
 			split /= 2
 		} else {
-			log.Tracef("len(shards)=%v: Payment was made, trying "+
+			tracef("len(shards)=%v: Payment was made, trying "+
 				"to pay remaining sats %v", shard, amt)
 
 			split = amt
 		}
 	}
 
-	log.Tracef("Payment is not routable, remaining amount that can't be "+
+	tracef("Payment is not routable, remaining amount that can't be "+
 		"sent: %v sats", amt)
 
 	logLocalBalances(maxParts)

loopd/swapclient_server_test.go

@@ -491,7 +491,8 @@ func TestValidateLoopOutRequest(t *testing.T) {
 			logger := btclog.NewSLogger(
 				btclog.NewDefaultHandler(os.Stdout),
 			)
-			log = logger.SubSystem(Subsystem)
+			setLogger(logger.SubSystem(Subsystem))
+
 			conf, err := validateLoopOutRequest(
 				ctx, lnd.Client, &test.chain, req,
 				test.destAddr, test.maxParts,

loopd/utils.go

@@ -57,12 +57,12 @@ func getClient(cfg *Config, swapDb loopdb.SwapStore,
 	}
 
 	if cfg.MaxL402Cost == defaultCost && cfg.MaxLSATCost != 0 {
-		log.Warnf("Option maxlsatcost is deprecated and will be " +
+		warnf("Option maxlsatcost is deprecated and will be " +
 			"removed. Switch to maxl402cost.")
 		clientConfig.MaxL402Cost = btcutil.Amount(cfg.MaxLSATCost)
 	}
 	if cfg.MaxL402Fee == defaultFee && cfg.MaxLSATFee != 0 {
-		log.Warnf("Option maxlsatfee is deprecated and will be " +
+		warnf("Option maxlsatfee is deprecated and will be " +
 			"removed. Switch to maxl402fee.")
 		clientConfig.MaxL402Fee = btcutil.Amount(cfg.MaxLSATFee)
 	}
@@ -87,7 +87,7 @@ func openDatabase(cfg *Config, chainParams *chaincfg.Params) (loopdb.SwapStore,
 	)
 	switch cfg.DatabaseBackend {
 	case DatabaseBackendSqlite:
-		log.Infof("Opening sqlite3 database at: %v",
+		infof("Opening sqlite3 database at: %v",
 			cfg.Sqlite.DatabaseFileName)
 
 		db, err = loopdb.NewSqliteStore(cfg.Sqlite, chainParams)
@@ -97,7 +97,7 @@ func openDatabase(cfg *Config, chainParams *chaincfg.Params) (loopdb.SwapStore,
 		baseDb = *db.(*loopdb.SqliteSwapStore).BaseDB
 
 	case DatabaseBackendPostgres:
-		log.Infof("Opening postgres database at: %v",
+		infof("Opening postgres database at: %v",
 			cfg.Postgres.DSN(true))
 
 		db, err = loopdb.NewPostgresStore(cfg.Postgres, chainParams)