all: Use context in lib/dialer (#6177)

* all: Use context in lib/dialer

* a bit slimmer

* https://github.com/syncthing/syncthing/pull/5753

* bot

* missed adding debug.go

* errors.Cause

* simultaneous dialing

* anti-leak

cmd/strelaypoolsrv/main.go

@@ -7,6 +7,7 @@ package main
 import (
 	"bytes"
 	"compress/gzip"
+	"context"
 	"crypto/tls"
 	"encoding/json"
 	"flag"
@@ -480,7 +481,7 @@ func handleRelayTest(request request) {
 	if debug {
 		log.Println("Request for", request.relay)
 	}
-	if !client.TestRelay(request.relay.uri, []tls.Certificate{testCert}, time.Second, 2*time.Second, 3) {
+	if !client.TestRelay(context.TODO(), request.relay.uri, []tls.Certificate{testCert}, time.Second, 2*time.Second, 3) {
 		if debug {
 			log.Println("Test for relay", request.relay, "failed")
 		}

cmd/strelaysrv/testutil/main.go

@@ -4,6 +4,7 @@ package main
 
 import (
 	"bufio"
+	"context"
 	"crypto/tls"
 	"flag"
 	"log"
@@ -19,6 +20,8 @@ import (
 )
 
 func main() {
+	ctx := context.Background()
+
 	log.SetOutput(os.Stdout)
 	log.SetFlags(log.LstdFlags | log.Lshortfile)
 
@@ -76,7 +79,7 @@ func main() {
 		}()
 
 		for {
-			conn, err := client.JoinSession(<-recv)
+			conn, err := client.JoinSession(ctx, <-recv)
 			if err != nil {
 				log.Fatalln("Failed to join", err)
 			}
@@ -90,13 +93,13 @@ func main() {
 			log.Fatal(err)
 		}
 
-		invite, err := client.GetInvitationFromRelay(uri, id, []tls.Certificate{cert}, 10*time.Second)
+		invite, err := client.GetInvitationFromRelay(ctx, uri, id, []tls.Certificate{cert}, 10*time.Second)
 		if err != nil {
 			log.Fatal(err)
 		}
 
 		log.Println("Received invitation", invite)
-		conn, err := client.JoinSession(invite)
+		conn, err := client.JoinSession(ctx, invite)
 		if err != nil {
 			log.Fatalln("Failed to join", err)
 		}
@@ -104,7 +107,7 @@ func main() {
 		connectToStdio(stdin, conn)
 		log.Println("Finished", conn.RemoteAddr(), conn.LocalAddr())
 	} else if test {
-		if client.TestRelay(uri, []tls.Certificate{cert}, time.Second, 2*time.Second, 4) {
+		if client.TestRelay(ctx, uri, []tls.Certificate{cert}, time.Second, 2*time.Second, 4) {
 			log.Println("OK")
 		} else {
 			log.Println("FAIL")

cmd/syncthing/main.go

@@ -512,7 +512,7 @@ func upgradeViaRest() error {
 	r.Header.Set("X-API-Key", cfg.GUI().APIKey)
 
 	tr := &http.Transport{
-		Dial:            dialer.Dial,
+		DialContext:     dialer.DialContext,
 		Proxy:           http.ProxyFromEnvironment,
 		TLSClientConfig: &tls.Config{InsecureSkipVerify: true},
 	}