Refactor to slightly improve memory safety of TeamWifiStatus.

field/arena.go

@@ -84,12 +84,13 @@ type Arena struct {
 }
 
 type AllianceStation struct {
-	DsConn   *DriverStationConnection
-	Ethernet bool
-	Astop    bool
-	Estop    bool
-	Bypass   bool
-	Team     *model.Team
+	DsConn     *DriverStationConnection
+	Ethernet   bool
+	Astop      bool
+	Estop      bool
+	Bypass     bool
+	Team       *model.Team
+	WifiStatus network.TeamWifiStatus
 }
 
 // Creates the arena and sets it to its initial state.
@@ -98,16 +99,6 @@ func NewArena(dbPath string) (*Arena, error) {
 	arena.configureNotifiers()
 	arena.Plc = new(plc.ModbusPlc)
 
-	var err error
-	arena.Database, err = model.OpenDatabase(dbPath)
-	if err != nil {
-		return nil, err
-	}
-	err = arena.LoadSettings()
-	if err != nil {
-		return nil, err
-	}
-
 	arena.AllianceStations = make(map[string]*AllianceStation)
 	arena.AllianceStations["R1"] = new(AllianceStation)
 	arena.AllianceStations["R2"] = new(AllianceStation)
@@ -118,6 +109,16 @@ func NewArena(dbPath string) (*Arena, error) {
 
 	arena.Displays = make(map[string]*Display)
 
+	var err error
+	arena.Database, err = model.OpenDatabase(dbPath)
+	if err != nil {
+		return nil, err
+	}
+	err = arena.LoadSettings()
+	if err != nil {
+		return nil, err
+	}
+
 	arena.ScoringPanelRegistry.initialize()
 
 	// Load empty match as current.
@@ -144,13 +145,43 @@ func (arena *Arena) LoadSettings() error {
 	arena.EventSettings = settings
 
 	// Initialize the components that depend on settings.
+	var accessPoint1WifiStatuses, accessPoint2WifiStatuses [6]*network.TeamWifiStatus
+	if arena.EventSettings.Ap2TeamChannel == 0 {
+		accessPoint1WifiStatuses = [6]*network.TeamWifiStatus{
+			&arena.AllianceStations["R1"].WifiStatus,
+			&arena.AllianceStations["R2"].WifiStatus,
+			&arena.AllianceStations["R3"].WifiStatus,
+			&arena.AllianceStations["B1"].WifiStatus,
+			&arena.AllianceStations["B2"].WifiStatus,
+			&arena.AllianceStations["B3"].WifiStatus,
+		}
+	} else {
+		accessPoint1WifiStatuses = [6]*network.TeamWifiStatus{
+			&arena.AllianceStations["R1"].WifiStatus,
+			&arena.AllianceStations["R2"].WifiStatus,
+			&arena.AllianceStations["R3"].WifiStatus,
+			nil,
+			nil,
+			nil,
+		}
+		accessPoint2WifiStatuses = [6]*network.TeamWifiStatus{
+			nil,
+			nil,
+			nil,
+			&arena.AllianceStations["B1"].WifiStatus,
+			&arena.AllianceStations["B2"].WifiStatus,
+			&arena.AllianceStations["B3"].WifiStatus,
+		}
+	}
+
 	arena.accessPoint.SetSettings(
 		settings.ApType == "vivid",
 		settings.ApAddress,
 		settings.ApUsername,
 		settings.ApPassword,
 		settings.ApTeamChannel,
 		settings.NetworkSecurityEnabled,
+		accessPoint1WifiStatuses,
 	)
 	arena.accessPoint2.SetSettings(
 		settings.ApType == "vivid",
@@ -159,6 +190,7 @@ func (arena *Arena) LoadSettings() error {
 		settings.Ap2Password,
 		settings.Ap2TeamChannel,
 		settings.NetworkSecurityEnabled,
+		accessPoint2WifiStatuses,
 	)
 	arena.networkSwitch = network.NewSwitch(settings.SwitchAddress, settings.SwitchPassword)
 	arena.Plc.SetAddress(settings.PlcAddress)
@@ -370,20 +402,10 @@ func (arena *Arena) StartMatch() error {
 		}
 		arena.updateCycleTime(arena.CurrentMatch.StartedAt)
 
-		// Convert AP team wifi network status array to a map by station for ease of client use.
-		teamWifiStatuses := make(map[string]*network.TeamWifiStatus)
-		for i, station := range []string{"R1", "R2", "R3", "B1", "B2", "B3"} {
-			if arena.EventSettings.Ap2TeamChannel == 0 || i < 3 {
-				teamWifiStatuses[station] = &arena.accessPoint.TeamWifiStatuses[i]
-			} else {
-				teamWifiStatuses[station] = &arena.accessPoint2.TeamWifiStatuses[i]
-			}
-		}
-
 		// Save the missed packet count to subtract it from the running count.
-		for station, allianceStation := range arena.AllianceStations {
+		for _, allianceStation := range arena.AllianceStations {
 			if allianceStation.DsConn != nil {
-				err = allianceStation.DsConn.signalMatchStart(arena.CurrentMatch, teamWifiStatuses[station])
+				err = allianceStation.DsConn.signalMatchStart(arena.CurrentMatch, &allianceStation.WifiStatus)
 				if err != nil {
 					log.Println(err)
 				}

field/arena_notifiers.go

@@ -8,7 +8,6 @@ package field
 import (
 	"github.com/Team254/cheesy-arena/game"
 	"github.com/Team254/cheesy-arena/model"
-	"github.com/Team254/cheesy-arena/network"
 	"github.com/Team254/cheesy-arena/playoff"
 	"github.com/Team254/cheesy-arena/websocket"
 	"strconv"
@@ -73,28 +72,23 @@ func (arena *Arena) generateAllianceStationDisplayModeMessage() any {
 }
 
 func (arena *Arena) generateArenaStatusMessage() any {
-	// Convert AP team wifi network status array to a map by station for ease of client use.
-	teamWifiStatuses := make(map[string]network.TeamWifiStatus)
-	for i, station := range []string{"R1", "R2", "R3", "B1", "B2", "B3"} {
-		if arena.EventSettings.Ap2TeamChannel == 0 || i < 3 {
-			teamWifiStatuses[station] = arena.accessPoint.TeamWifiStatuses[i]
-		} else {
-			teamWifiStatuses[station] = arena.accessPoint2.TeamWifiStatuses[i]
-		}
-	}
-
 	return &struct {
 		MatchId          int
 		AllianceStations map[string]*AllianceStation
-		TeamWifiStatuses map[string]network.TeamWifiStatus
 		MatchState
 		CanStartMatch         bool
 		PlcIsHealthy          bool
 		FieldEstop            bool
 		PlcArmorBlockStatuses map[string]bool
-	}{arena.CurrentMatch.Id, arena.AllianceStations, teamWifiStatuses, arena.MatchState,
-		arena.checkCanStartMatch() == nil, arena.Plc.IsHealthy(), arena.Plc.GetFieldEstop(),
-		arena.Plc.GetArmorBlockStatuses()}
+	}{
+		arena.CurrentMatch.Id,
+		arena.AllianceStations,
+		arena.MatchState,
+		arena.checkCanStartMatch() == nil,
+		arena.Plc.IsHealthy(),
+		arena.Plc.GetFieldEstop(),
+		arena.Plc.GetArmorBlockStatuses(),
+	}
 }
 
 func (arena *Arena) generateAudienceDisplayModeMessage() any {

network/access_point.go

@@ -38,7 +38,7 @@ type AccessPoint struct {
 	teamChannel            int
 	networkSecurityEnabled bool
 	configRequestChan      chan [6]*model.Team
-	TeamWifiStatuses       [6]TeamWifiStatus
+	TeamWifiStatuses       [6]*TeamWifiStatus
 	initialStatusesFetched bool
 }
 
@@ -57,14 +57,19 @@ type sshOutput struct {
 }
 
 func (ap *AccessPoint) SetSettings(
-	isVividType bool, address, username, password string, teamChannel int, networkSecurityEnabled bool,
+	isVividType bool,
+	address, username, password string,
+	teamChannel int,
+	networkSecurityEnabled bool,
+	wifiStatuses [6]*TeamWifiStatus,
 ) {
 	ap.isVividType = isVividType
 	ap.address = address
 	ap.username = username
 	ap.password = password
 	ap.teamChannel = teamChannel
 	ap.networkSecurityEnabled = networkSecurityEnabled
+	ap.TeamWifiStatuses = wifiStatuses
 
 	// Create config channel the first time this method is called.
 	if ap.configRequestChan == nil {
@@ -207,7 +212,7 @@ func (ap *AccessPoint) updateTeamWifiStatuses() error {
 	output, err := ap.runCommand("iwinfo")
 	if err == nil {
 		logWifiInfo(output)
-		err = decodeWifiInfo(output, ap.TeamWifiStatuses[:])
+		err = ap.decodeWifiInfo(output)
 	}
 
 	if err != nil {
@@ -303,7 +308,7 @@ func logWifiInfo(wifiInfo string) {
 }
 
 // Parses the given output from the "iwinfo" command on the AP and updates the given status structure with the result.
-func decodeWifiInfo(wifiInfo string, statuses []TeamWifiStatus) error {
+func (ap *AccessPoint) decodeWifiInfo(wifiInfo string) error {
 	ssidRe := regexp.MustCompile("ESSID: \"([-\\w ]*)\"")
 	ssids := ssidRe.FindAllStringSubmatch(wifiInfo, -1)
 
@@ -312,9 +317,11 @@ func decodeWifiInfo(wifiInfo string, statuses []TeamWifiStatus) error {
 		return fmt.Errorf("Could not parse wifi info; expected 6 team networks, got %d.", len(ssids))
 	}
 
-	for i := range statuses {
-		ssid := ssids[i][1]
-		statuses[i].TeamId, _ = strconv.Atoi(ssid) // Any non-numeric SSIDs will be represented by a zero.
+	for i, wifiStatus := range ap.TeamWifiStatuses {
+		if wifiStatus != nil {
+			ssid := ssids[i][1]
+			wifiStatus.TeamId, _ = strconv.Atoi(ssid) // Any non-numeric SSIDs will be represented by a zero.
+		}
 	}
 
 	return nil

network/access_point_test.go

@@ -131,49 +131,57 @@ func TestGenerateTeamAccessPointConfigForVividHosting(t *testing.T) {
 }
 
 func TestDecodeWifiInfo(t *testing.T) {
-	var statuses [6]TeamWifiStatus
+	statuses := [6]*TeamWifiStatus{
+		nil,
+		&TeamWifiStatus{},
+		&TeamWifiStatus{},
+		&TeamWifiStatus{},
+		nil,
+		&TeamWifiStatus{},
+	}
+	ap := AccessPoint{isVividType: true, TeamWifiStatuses: statuses}
 
 	// Test with zero team networks configured.
 	output, err := ioutil.ReadFile("testdata/iwinfo_0_teams.txt")
 	if assert.Nil(t, err) {
-		assert.Nil(t, decodeWifiInfo(string(output), statuses[:]))
-		assert.Equal(t, 0, statuses[0].TeamId)
+		assert.Nil(t, ap.decodeWifiInfo(string(output)))
+		assert.Nil(t, statuses[0])
 		assert.Equal(t, 0, statuses[1].TeamId)
 		assert.Equal(t, 0, statuses[2].TeamId)
 		assert.Equal(t, 0, statuses[3].TeamId)
-		assert.Equal(t, 0, statuses[4].TeamId)
+		assert.Nil(t, statuses[4])
 		assert.Equal(t, 0, statuses[5].TeamId)
 	}
 
 	// Test with two team networks configured.
 	output, err = ioutil.ReadFile("testdata/iwinfo_2_teams.txt")
 	if assert.Nil(t, err) {
-		assert.Nil(t, decodeWifiInfo(string(output), statuses[:]))
-		assert.Equal(t, 0, statuses[0].TeamId)
+		assert.Nil(t, ap.decodeWifiInfo(string(output)))
+		assert.Nil(t, statuses[0])
 		assert.Equal(t, 2471, statuses[1].TeamId)
 		assert.Equal(t, 0, statuses[2].TeamId)
 		assert.Equal(t, 254, statuses[3].TeamId)
-		assert.Equal(t, 0, statuses[4].TeamId)
+		assert.Nil(t, statuses[4])
 		assert.Equal(t, 0, statuses[5].TeamId)
 	}
 
 	// Test with six team networks configured.
 	output, err = ioutil.ReadFile("testdata/iwinfo_6_teams.txt")
 	if assert.Nil(t, err) {
-		assert.Nil(t, decodeWifiInfo(string(output), statuses[:]))
-		assert.Equal(t, 254, statuses[0].TeamId)
+		assert.Nil(t, ap.decodeWifiInfo(string(output)))
+		assert.Nil(t, statuses[0])
 		assert.Equal(t, 1678, statuses[1].TeamId)
 		assert.Equal(t, 2910, statuses[2].TeamId)
 		assert.Equal(t, 604, statuses[3].TeamId)
-		assert.Equal(t, 8, statuses[4].TeamId)
+		assert.Nil(t, statuses[4])
 		assert.Equal(t, 2471, statuses[5].TeamId)
 	}
 
 	// Test with invalid input.
-	assert.NotNil(t, decodeWifiInfo("", statuses[:]))
+	assert.NotNil(t, ap.decodeWifiInfo(""))
 	output, err = ioutil.ReadFile("testdata/iwinfo_invalid.txt")
 	if assert.Nil(t, err) {
-		assert.NotNil(t, decodeWifiInfo(string(output), statuses[:]))
+		assert.NotNil(t, ap.decodeWifiInfo(string(output)))
 	}
 }
 

static/js/field_monitor_display.js

@@ -18,7 +18,7 @@ var handleArenaStatus = function(data) {
   } else if (currentMatchId !== data.MatchId) {
     location.reload();
   }
-	
+
   $.each(data.AllianceStations, function(station, stationStatus) {
     // Select the DOM elements corresponding to the team station.
     var teamElementPrefix;
@@ -75,7 +75,7 @@ var handleArenaStatus = function(data) {
       teamEthernetElement.text("ETH");
     }
 
-    var wifiStatus = data.TeamWifiStatuses[station];
+    const wifiStatus = stationStatus.WifiStatus;
     teamRadioTextElement.text(wifiStatus.TeamId);
 
     if (stationStatus.DsConn) {
@@ -205,7 +205,7 @@ $(function() {
     redSide = "left";
     blueSide = "right";
   }
-  
+
   //Read if display to be used in a Driver Station, ignore FTA flag if so.
   var driverStation = urlParams.get("ds");
   if (driverStation === "true") {
@@ -215,7 +215,7 @@ $(function() {
   $(".fta-dependent").attr("data-fta", urlParams.get("fta"));
   $(".ds-dependent").attr("data-ds", driverStation);
   }
-  
+
   $(".reversible-left").attr("data-reversed", reversed);
   $(".reversible-right").attr("data-reversed", reversed);
 

static/js/match_play.js

@@ -109,7 +109,7 @@ const getTeamNumber = function(station) {
 const handleArenaStatus = function(data) {
   // Update the team status view.
   $.each(data.AllianceStations, function(station, stationStatus) {
-    const wifiStatus = data.TeamWifiStatuses[station];
+    const wifiStatus = stationStatus.WifiStatus;
     $("#status" + station + " .radio-status").text(wifiStatus.TeamId);
 
     if (stationStatus.DsConn) {