[all] support for OT Posix node with RCP using realtime UART V2

.github/workflows/develop.yml

@@ -1,4 +1,4 @@
-# Copyright (c) 2020-2025, The OTNS Authors.
+# Copyright (c) 2020-2026, The OTNS Authors.
 # All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
@@ -79,11 +79,9 @@ jobs:
           fi
           ./script/install
       - name: Build custom OT node
-        # FIXME: OT_CMAKE_NINJA_TARGET used to exclude tests, because test_platform.cpp is missing otPlatAssertFail()
         run: |
           cd ot-rfsim
-          OT_CMAKE_NINJA_TARGET="ot-cli-ftd ot-cli-mtd" ./script/build -DOT_HISTORY_TRACKER=ON
-          # ./script/build -DOT_HISTORY_TRACKER=ON # this should be the command above (after the OT fix)
+          ./script/build -DOT_HISTORY_TRACKER=ON
       - name: Setup dev environment
         run: |
           ./script/setup-dev

cli/CmdRunner.go

@@ -331,6 +331,12 @@ func (rt *CmdRunner) execute(cmd *Command, output io.Writer) {
 }
 
 func (rt *CmdRunner) executeGo(cc *CommandContext, cmd *GoCmd) {
+	// verify that we're not in realtime mode.
+	if rt.sim.GetConfig().Realtime {
+		cc.errorf("cannot use 'go' commands in -realtime mode")
+		return
+	}
+
 	// determine duration and desired speed of the Go simulation period.
 	timeDurToGo, err := time.ParseDuration(cmd.Time)
 	if cmd.Ever == nil && err != nil {
@@ -382,6 +388,10 @@ func (rt *CmdRunner) executeAutoGo(cc *CommandContext, cmd *AutoGoCmd) {
 			}
 			cc.outputf("%d\n", autoGoInt)
 		} else {
+			if rt.sim.GetConfig().Realtime && cmd.Val.Yes == nil {
+				cc.errorf("cannot set 'autogo' to false in -realtime mode")
+				return
+			}
 			sim.SetAutoGo(cmd.Val.Yes != nil)
 		}
 	})
@@ -713,7 +723,7 @@ func (rt *CmdRunner) executeLsNodes(cc *CommandContext, cmd *NodesCmd) {
 		for _, nodeId := range sim.GetNodes() {
 			snode, dnode := rt.getNodeById(nodeId)
 			var line strings.Builder
-			line.WriteString(fmt.Sprintf("id=%d\ttype=%-6s  extaddr=%016x  rloc16=%04x  x=%-2d\ty=%-3d\tz=%-3d\tstate=%s\tfailed=%v", nodeId, dnode.Type, dnode.ExtAddr, dnode.Rloc16,
+			line.WriteString(fmt.Sprintf("id=%d\ttype=%-6s  extaddr=%016x  rloc16=%04x  x=%-2d\ty=%-3d\tz=%-3d\tstate=%s\tfailed=%v", nodeId, snode.GetType(), dnode.ExtAddr, dnode.Rloc16,
 				dnode.X, dnode.Y, dnode.Z, dnode.Role, dnode.IsFailed()))
 			line.WriteString(fmt.Sprintf("\texe=%s", snode.GetExecutableName()))
 			cc.outputf("%s\n", line.String())
@@ -1288,6 +1298,16 @@ func (rt *CmdRunner) executeExe(cc *CommandContext, cmd *ExeCmd) {
 					ec.Br = cmd.Path
 				}
 				cc.outputf("br : %s\n", ec.Br)
+			case RCP:
+				if isSetPath {
+					ec.Rcp = cmd.Path
+				}
+				cc.outputf("rcp: %s\n", ec.Rcp)
+			case HOST:
+				if isSetPath {
+					ec.RcpHost = cmd.Path
+				}
+				cc.outputf("host: %s\n", ec.RcpHost)
 			}
 			return
 		} else if isSetDefault && !isSetPath && !isSetNodeType && !isSetVersion {
@@ -1307,11 +1327,15 @@ func (rt *CmdRunner) executeExe(cc *CommandContext, cmd *ExeCmd) {
 		cc.outputf("mtd: %s\n", ec.Mtd)
 		cc.outputf("br : %s\n", ec.Br)
 		cc.outputf("matter: %s\n", ec.Matter)
+		cc.outputf("rcp: %s\n", ec.Rcp)
+		cc.outputf("host: %s\n", ec.RcpHost)
 		cc.outputf("Executables search path: %s\n", ec.SearchPathsString())
 		cc.outputf("Detected FTD path      : %s\n", ec.FindExecutable(ec.Ftd))
 		cc.outputf("Detected MTD path      : %s\n", ec.FindExecutable(ec.Mtd))
 		cc.outputf("Detected BR path       : %s\n", ec.FindExecutable(ec.Br))
 		cc.outputf("Detected Matter path   : %s\n", ec.FindExecutable(ec.Matter))
+		cc.outputf("Detected RCP path      : %s\n", ec.FindExecutable(ec.Rcp))
+		cc.outputf("Detected RCP Host path : %s\n", ec.FindExecutable(ec.RcpHost))
 	})
 }
 

cli/README.md

@@ -54,7 +54,7 @@ Add a node to the simulation and get the node ID.
 add <type> [x <x>] [y <y>] [rr <radio-range>] [id <node-id>] [restore] [exe <path>] [v11|v12|v13|v14]
 ```
 
-The `<type>` can be `router`, `fed`, `med`, `sed`, `ssed`, `br` (Border Router), `wifi` (for a Wi-Fi interferer node), or `matter`. Node ID can be specified using the `id` parameter, otherwise OTNS assigns the next available one. If the `restore` option is specified, the node restores its network configuration from persistent storage.
+The `<type>` can be `router`, `fed`, `med`, `sed`, `ssed`, `br` (Border Router), `rcp`, `wifi` (for a Wi-Fi interferer node), or `matter`. Node ID can be specified using the `id` parameter, otherwise OTNS assigns the next available one. If the `restore` option is specified, the node restores its network configuration from persistent storage.
 
 The (advanced) `exe` option can be used to specify a node executable for the new node; either a name only which is then located in the default search paths, or a full abs or rel pathname pointing to the executable to use.
 
@@ -254,10 +254,14 @@ The line `Executables search path` lists the paths where the executable of that
 ftd: ot-cli-ftd
 mtd: ot-cli-mtd
 br : ot-cli-ftd_br
+rcp: ot-rcp
+host: ot-cli
 Executables search path: [".", "./ot-rfsim/ot-versions", "./build/bin"]
 Detected FTD path      : ./ot-rfsim/ot-versions/ot-cli-ftd
 Detected MTD path      : ./ot-rfsim/ot-versions/ot-cli-mtd
 Detected BR path       : ./ot-rfsim/ot-versions/ot-cli-ftd_br
+Detected RCP path      : ./ot-rfsim/ot-versions/ot-rcp
+Detected RCP Host path : ./ot-rfsim/ot-versions/ot-cli
 Done
 >
 ```
@@ -299,10 +303,10 @@ Done
 #### exe: Change OT executable for particular node type
 
 ```shell
-exe ( ftd | mtd | br ) ["<path-or-filename-of-executable>"]
+exe ( ftd | mtd | br | rcp | host) ["<path-or-filename-of-executable>"]
 ```
 
-Change the OpenThread (OT) executable, or shell script, for a particular node types as provided in the first argument (ftd, mtd, or br). The path-or-filename is provided in the second argument and will replace the current default executable for that node type. If only the first argument is given, the current executable for this node type will be listed and no change is made. If only a filename is given, without full path, the executable will be located using the search paths listed under `Executables search path`.
+Change the OpenThread (OT) executable, or shell script, for a particular node types as provided in the first argument (ftd, mtd, br, rcp or host). The path-or-filename is provided in the second argument and will replace the current default executable for that node type. If only the first argument is given, the current executable for this node type will be listed and no change is made. If only a filename is given, without full path, the executable will be located using the search paths listed under `Executables search path`.
 
 Note that the default executable is used when normally adding a node using the GUI or a command such as `add router x 200 y 200` where the executable is not explictly specified. The "exe" argument of the "add" command will however override the default executable always, for example as in the command `add router x 200 y 200 exe "./my-override-ot-cli-ftd"` .
 
@@ -317,10 +321,14 @@ Done
 ftd: ./my-ot-cli-ftd
 mtd: ot-cli-mtd
 br : ./br-script.sh
+rcp: ot-rcp
+host: ot-cli
 Executables search path: [".", "./ot-rfsim/ot-versions", "./build/bin"]
 Detected FTD path      : ./my-ot-cli-ftd
 Detected MTD path      : ./ot-rfsim/ot-versions/ot-cli-mtd
 Detected BR path       : ./br-script.sh
+Detected RCP path      : ./ot-rfsim/ot-versions/ot-rcp
+Detected RCP Host path : ./ot-rfsim/ot-versions/ot-cli
 Done
 > exe mtd
 mtd: ot-cli-mtd
@@ -349,6 +357,8 @@ go <duration> [speed <particular-speed>]
 
 Simulate for a specified time in seconds or indefinitely (duration=`ever`). It is required in `-autogo=false` mode to advance the simulation. In `-autogo=true` mode, it can be optionally used to advance the simulation quickly by the given time. For example, in a paused simulation to quickly advance 64 us, 1 ms, 10 seconds, or an hour. The optional `speed` argument can be given to do the simulation at that speed e.g. to see the animations and log output better. The `duration` argument can optionally end with a time unit suffix: `us`, `ms`, `s`, `m`, or `h`.
 
+In `-realtime` mode this command is not available and will always return an error.
+
 ```bash
 > go 1
 Done

cli/ast.go

@@ -1,4 +1,4 @@
-// Copyright (c) 2020-2025, The OTNS Authors.
+// Copyright (c) 2020-2026, The OTNS Authors.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -312,7 +312,7 @@ type AddCmd struct {
 
 // noinspection GoVetStructTag
 type NodeTypeOrRole struct {
-	Val string `@("router"|"reed"|"fed"|"med"|"sed"|"ssed"|"br"|"mtd"|"ftd"|"wifi"|"matter")` //nolint
+	Val string `@("router"|"reed"|"fed"|"med"|"sed"|"ssed"|"br"|"mtd"|"ftd"|"wifi"|"matter"|"rcp"|"host")` //nolint
 }
 
 // noinspection GoVetStructTag

dispatcher/FailureCtrl_test.go

@@ -1,4 +1,4 @@
-// Copyright (c) 2020-2024, The OTNS Authors.
+// Copyright (c) 2020-2026, The OTNS Authors.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -44,7 +44,10 @@ type mockDispatcherCallback struct {
 func (m mockDispatcherCallback) OnUartWrite(nodeid NodeId, data []byte) {
 }
 
-func (m mockDispatcherCallback) OnLogWrite(nodeid NodeId, data []byte) {
+func (m mockDispatcherCallback) OnUartDisconnected(nodeid NodeId) {
+}
+
+func (m mockDispatcherCallback) OnLogWrite(nodeid NodeId, data []byte, isFromHost bool) {
 }
 
 func (m mockDispatcherCallback) OnNextEventTime(nextTimeUs uint64) {

dispatcher/Node.go

@@ -78,11 +78,11 @@ type Node struct {
 	CurTime     uint64
 	Mode        NodeMode
 	Role        OtDeviceRole
-	Type        string
 	RadioNode   *radiomodel.RadioNode
 
+	cfg             *NodeConfig
 	conn            net.Conn
-	hasDisconnected bool // keeps track of whether the node process disconnected
+	hasDisconnected bool // keeps track of whether the node process Unix socket disconnected
 	msgId           uint64
 	err             error
 	failureCtrl     *FailureCtrl // keeps track of radio failures scheduled by OTNS
@@ -106,41 +106,35 @@ func newNode(d *Dispatcher, nodeid NodeId, cfg *NodeConfig) *Node {
 	}
 
 	nc := &Node{
-		D:               d,
-		Id:              nodeid,
-		CurTime:         d.CurTime,
-		CreateTime:      d.CurTime,
-		X:               cfg.X,
-		Y:               cfg.Y,
-		Z:               cfg.Z,
-		ExtAddr:         InvalidExtAddr,
-		Rloc16:          InvalidRloc16,
-		Mode:            DefaultNodeMode(),
-		Role:            OtDeviceRoleDisabled,
-		Type:            cfg.Type,
-		conn:            nil, // connection will be set when first event is received from node.
-		hasDisconnected: false,
-		err:             nil, // keep track of connection errors.
-		RadioNode:       radiomodel.NewRadioNode(nodeid, radioCfg),
-		joinerState:     OtJoinerStateIdle,
-		logger:          logger.GetNodeLogger(d.cfg.OutputDir, d.cfg.SimulationId, cfg),
+		D:           d,
+		Id:          nodeid,
+		CurTime:     d.CurTime,
+		CreateTime:  d.CurTime,
+		X:           cfg.X,
+		Y:           cfg.Y,
+		Z:           cfg.Z,
+		ExtAddr:     InvalidExtAddr,
+		Rloc16:      InvalidRloc16,
+		Mode:        DefaultNodeMode(),
+		Role:        OtDeviceRoleDisabled,
+		cfg:         cfg,
+		conn:        nil, // connection will be set when first event is received from node.
+		err:         nil, // keep track of connection errors.
+		RadioNode:   radiomodel.NewRadioNode(nodeid, radioCfg),
+		joinerState: OtJoinerStateIdle,
+		logger:      logger.GetNodeLogger(d.cfg.OutputDir, d.cfg.SimulationId, cfg),
 	}
 
 	nc.failureCtrl = newFailureCtrl(nc, NonFailTime)
 	return nc
 }
 
-func (node *Node) exit() {
-	node.DisconnectSocket()
-	node.hasDisconnected = true
-	node.logger.Close()
-}
-
 // DisconnectSocket closes the socket connection (if any) with the node process.
 func (node *Node) DisconnectSocket() {
+	node.hasDisconnected = true
 	if node.conn != nil {
 		err := node.conn.Close()
-		if err == nil {
+		if err == nil { // if already closed, don't print the log message.
 			logger.Tracef("Closed dispatcher node %d socket connection.", node.Id)
 		}
 	}
@@ -150,9 +144,8 @@ func (node *Node) String() string {
 	return GetNodeName(node.Id)
 }
 
-// SendToUART sends any data to virtual time UART of the node.
-func (node *Node) SendToUART(data []byte) error {
-	var err error
+// SendToVirtualUART sends any data to the virtual-time UART of the node.
+func (node *Node) SendToVirtualUART(data []byte) error {
 	evt := &Event{
 		Timestamp: node.D.CurTime,
 		Type:      EventTypeUartWrite,
@@ -162,10 +155,7 @@ func (node *Node) SendToUART(data []byte) error {
 
 	node.logger.Tracef("UART-write: %s", data)
 	node.sendEvent(evt)
-	if node.err != nil {
-		err = node.err
-	}
-	return err
+	return node.err
 }
 
 func (node *Node) SendRfSimEvent(writeValue bool, param RfSimParam, value RfSimParamValue) error {
@@ -220,11 +210,14 @@ func (node *Node) sendEvent(evt *Event) {
 	}
 
 	if err, wasSocketClosed := node.sendRawData(evt.Serialize()); err != nil {
+		socketClosedMsg := ""
 		if wasSocketClosed {
-			node.DisconnectSocket() // just in case peer closed it, also close locally.
+			socketClosedMsg = " (socket was closed)"
 		}
+		err = fmt.Errorf("send event %v failed%s: %w", evt, socketClosedMsg, err)
 		node.logger.Error(err)
 		node.err = err
+		node.DisconnectSocket()
 	} else {
 		node.D.setAlive(node.Id)
 	}
@@ -234,6 +227,7 @@ func (node *Node) sendEvent(evt *Event) {
 // a flag indicating whether the socket was closed by either side.
 func (node *Node) sendRawData(msg []byte) (error, bool) {
 	logger.AssertNotNil(node.conn)
+
 	if _, err := node.conn.Write(msg); err != nil {
 		if errors.Is(err, net.ErrClosed) || errors.Is(err, io.EOF) || errors.Is(err, syscall.EPIPE) {
 			return err, true