Implemented and fixed many issues

2026-08-21 23:24:48 +02:00
parent 14d5351a81
commit e03c60db25
52 changed files with 7726 additions and 769 deletions
@@ -0,0 +1,116 @@
+//go:build linux
+
+package wshub
+
+import (
+	"net"
+	"syscall"
+	"testing"
+	"time"
+)
+
+// setMulticastIf pins a socket's outgoing multicast interface (IP_MULTICAST_IF),
+// which is exactly what UDPStreamer/UDPSServer does with its `Interface` key.
+func setMulticastIf(t *testing.T, conn *net.UDPConn, ip [4]byte) {
+	t.Helper()
+	rc, err := conn.SyscallConn()
+	if err != nil {
+		t.Fatalf("SyscallConn: %v", err)
+	}
+	var sockErr error
+	if err := rc.Control(func(fd uintptr) {
+		sockErr = syscall.SetsockoptInet4Addr(int(fd), syscall.IPPROTO_IP, syscall.IP_MULTICAST_IF, ip)
+	}); err != nil {
+		t.Fatalf("Control: %v", err)
+	}
+	if sockErr != nil {
+		t.Fatalf("IP_MULTICAST_IF: %v", sockErr)
+	}
+}
+
+func TestInterfaceForIPResolvesLoopback(t *testing.T) {
+	ifi := interfaceForIP(net.ParseIP("127.0.0.1"))
+	if ifi == nil {
+		t.Fatal("no interface resolved for 127.0.0.1")
+	}
+	if ifi.Flags&net.FlagLoopback == 0 {
+		t.Fatalf("resolved %q for 127.0.0.1, which is not a loopback interface", ifi.Name)
+	}
+}
+
+func TestInterfaceForIPUnknownAddressIsNil(t *testing.T) {
+	// Unspecified and unassigned addresses must fall back to "let the kernel
+	// choose" rather than resolving to an arbitrary interface.
+	if ifi := interfaceForIP(net.IPv4zero); ifi != nil {
+		t.Fatalf("0.0.0.0 resolved to %q, want nil", ifi.Name)
+	}
+	if ifi := interfaceForIP(nil); ifi != nil {
+		t.Fatalf("nil IP resolved to %q, want nil", ifi.Name)
+	}
+	if ifi := interfaceForIP(net.ParseIP("203.0.113.42")); ifi != nil {
+		t.Fatalf("unassigned address resolved to %q, want nil", ifi.Name)
+	}
+}
+
+// TestMulticastJoinOnControlInterfaceReceivesData is the regression test for the
+// bug that left the web UI permanently blank: the hub joined the group with a
+// nil interface, so imr_interface stayed INADDR_ANY and the kernel picked the
+// default-route interface. A UDPStreamer configured with Interface = "127.0.0.1"
+// sends out the loopback instead, and every datagram was silently dropped.
+//
+// The sender here mimics that server exactly (IP_MULTICAST_IF = 127.0.0.1); the
+// receiver joins the way runMulticastSession now does, via the interface that
+// owns the control connection's local address.
+func TestMulticastJoinOnControlInterfaceReceivesData(t *testing.T) {
+	const group = "239.255.13.37"
+
+	ifi := interfaceForIP(net.ParseIP("127.0.0.1"))
+	if ifi == nil {
+		t.Skip("no loopback interface available")
+	}
+
+	rx, err := net.ListenMulticastUDP("udp4", ifi, &net.UDPAddr{IP: net.ParseIP(group), Port: 0})
+	if err != nil {
+		t.Fatalf("join %s on %s: %v", group, ifi.Name, err)
+	}
+	defer rx.Close()
+	port := rx.LocalAddr().(*net.UDPAddr).Port
+
+	tx, err := net.ListenUDP("udp4", &net.UDPAddr{IP: net.ParseIP("127.0.0.1")})
+	if err != nil {
+		t.Fatalf("sender socket: %v", err)
+	}
+	defer tx.Close()
+	setMulticastIf(t, tx, [4]byte{127, 0, 0, 1})
+
+	payload := []byte("UDPS-multicast-probe")
+	dst := &net.UDPAddr{IP: net.ParseIP(group), Port: port}
+
+	// Datagrams are lossy even on loopback if the join has not settled, so send
+	// a few and accept the first that lands.
+	done := make(chan struct{})
+	defer close(done)
+	go func() {
+		for {
+			select {
+			case <-done:
+				return
+			default:
+			}
+			tx.WriteToUDP(payload, dst)
+			time.Sleep(20 * time.Millisecond)
+		}
+	}()
+
+	buf := make([]byte, 128)
+	if err := rx.SetReadDeadline(time.Now().Add(3 * time.Second)); err != nil {
+		t.Fatal(err)
+	}
+	n, _, err := rx.ReadFromUDP(buf)
+	if err != nil {
+		t.Fatalf("no multicast received on %s within 3s: %v", ifi.Name, err)
+	}
+	if got := string(buf[:n]); got != string(payload) {
+		t.Fatalf("payload = %q, want %q", got, payload)
+	}
+}