Testing

pkg/ca/testca/server.go

@@ -29,13 +29,21 @@ type Server struct {
 	tcpLn net.Listener
 	udpCn *net.UDPConn
 
-	mu   sync.RWMutex
-	pvs  map[string]*serverPV
-	subs map[uint32]*serverSub // subID → sub
+	mu       sync.RWMutex
+	pvs      map[string]*serverPV
+	subs     map[uint32]*serverSub // subID → sub
+	getFault int                   // fault to inject on the next READ_NOTIFY
 
 	done chan struct{}
 }
 
+// Fault modes for SetGetFault, used to exercise the client's error paths.
+const (
+	GetFaultNone       = iota // serve replies normally
+	GetFaultDisconnect        // drop the connection mid-request
+	GetFaultCorrupt           // reply with an undecodable (too-short) payload
+)
+
 type serverPV struct {
 	spec PVSpec
 	mu   sync.RWMutex
@@ -43,11 +51,11 @@ type serverPV struct {
 }
 
 type serverSub struct {
-	pvName string
-	subID  uint32
-	cid    uint32
-	sid    uint32
-	conn   net.Conn
+	pvName  string
+	subID   uint32
+	cid     uint32
+	sid     uint32
+	conn    net.Conn
 	dbrType uint16
 	count   uint32
 }
@@ -93,6 +101,29 @@ func (s *Server) Close() {
 	s.udpCn.Close()
 }
 
+// SetGetFault arms a fault to be injected on the next READ_NOTIFY request.
+// It is reset to GetFaultNone after a single request is faulted.
+func (s *Server) SetGetFault(mode int) {
+	s.mu.Lock()
+	s.getFault = mode
+	s.mu.Unlock()
+}
+
+// Disconnect pushes a SERVER_DISCONN message to every connected subscriber,
+// simulating an orderly server shutdown that forces clients to reconnect.
+func (s *Server) Disconnect() {
+	msg := proto.BuildMessage(proto.Header{Command: proto.CmdServerDisc}, nil)
+	seen := make(map[net.Conn]bool)
+	s.mu.RLock()
+	for _, sub := range s.subs {
+		if sub.conn != nil && !seen[sub.conn] {
+			seen[sub.conn] = true
+			_, _ = sub.conn.Write(msg)
+		}
+	}
+	s.mu.RUnlock()
+}
+
 // SetValue updates a PV's value and pushes a monitor event to all subscribers.
 func (s *Server) SetValue(pvName string, val any) error {
 	s.mu.RLock()
@@ -350,6 +381,31 @@ func (s *Server) handleConn(conn net.Conn) {
 				continue
 			}
 
+			// Fault injection: consume a one-shot armed fault, if any.
+			s.mu.Lock()
+			fault := s.getFault
+			s.getFault = GetFaultNone
+			s.mu.Unlock()
+			switch fault {
+			case GetFaultDisconnect:
+				// Drop the connection mid-request: the client's in-flight GET
+				// unblocks with ok=false ("circuit disconnected during GET").
+				conn.Close()
+				return
+			case GetFaultCorrupt:
+				// Reply with a too-short payload so DecodeTimeValue fails
+				// ("failed to decode GET reply").
+				reply := proto.BuildMessage(proto.Header{
+					Command:    proto.CmdReadNotify,
+					DataType:   hdr.DataType,
+					DataCount:  hdr.DataCount,
+					Parameter1: cid,
+					Parameter2: ioid,
+				}, []byte{0, 0, 0, 0})
+				conn.Write(reply)
+				continue
+			}
+
 			s.mu.RLock()
 			pv := s.pvs[pvName]
 			s.mu.RUnlock()
@@ -591,7 +647,10 @@ func nullStr(b []byte) string {
 // Minimal io.Reader for proto.DecodeHeader                                   //
 // -------------------------------------------------------------------------- //
 
-type bytesReader struct{ b []byte; i int }
+type bytesReader struct {
+	b []byte
+	i int
+}
 
 func newBytesReader(b []byte) *bytesReader { return &bytesReader{b: b} }