Add mutex for traffic/network ops.

network.go

@@ -6,12 +6,14 @@ import (
 	"net"
 	"strconv"
 	"strings"
+	"sync"
 	"time"
 )
 
 var messageQueue chan []byte
 var outSockets map[string]*net.UDPConn
 var dhcpLeases map[string]string
+var netMutex *sync.Mutex
 
 // Read the "dhcpd.leases" file and parse out IP/hostname.
 func getDHCPLeases() (map[string]string, error) {
@@ -38,6 +40,8 @@ func getDHCPLeases() (map[string]string, error) {
 }
 
 func sendToAllConnectedClients(msg []byte) {
+	netMutex.Lock()
+	defer netMutex.Unlock()
 	for _, sock := range outSockets {
 		sock.Write(msg)
 	}
@@ -50,6 +54,8 @@ func getNetworkStats() int {
 
 // See who has a DHCP lease and make a UDP connection to each of them.
 func refreshConnectedClients() {
+	netMutex.Lock()
+	defer netMutex.Unlock()
 	validConnections := make(map[string]bool)
 	t, err := getDHCPLeases()
 	if err != nil {
@@ -111,6 +117,7 @@ func sendMsg(msg []byte) {
 func initNetwork() {
 	messageQueue = make(chan []byte, 1024) // Buffered channel, 1024 messages.
 	outSockets = make(map[string]*net.UDPConn)
+	netMutex = &sync.Mutex{}
 	refreshConnectedClients()
 	go messageQueueSender()
 }

traffic.go

@@ -3,12 +3,12 @@ package main
 import (
 	"encoding/hex"
 	"math"
+	"sync"
 	"time"
 )
 
 //-0b2b48fe3aef1f88621a0856110a31c01105c4e6c4e6c40a9a820300000000000000;rs=7;
 
-
 /*
 
 HDR:
@@ -67,8 +67,11 @@ type TrafficInfo struct {
 }
 
 var traffic map[uint32]TrafficInfo
+var trafficMutex *sync.Mutex
 
 func cleanupOldEntries() {
+	trafficMutex.Lock()
+	defer trafficMutex.Unlock()
 	for icao_addr, ti := range traffic {
 		if time.Since(ti.last_seen).Seconds() > float64(60) { //FIXME: 60 seconds with no update on this address - stop displaying.
 			delete(traffic, icao_addr)
@@ -77,6 +80,8 @@ func cleanupOldEntries() {
 }
 
 func sendTrafficUpdates() {
+	trafficMutex.Lock()
+	defer trafficMutex.Unlock()
 	cleanupOldEntries()
 	for _, ti := range traffic {
 		makeTrafficReport(ti)
@@ -85,6 +90,7 @@ func sendTrafficUpdates() {
 
 func initTraffic() {
 	traffic = make(map[uint32]TrafficInfo)
+	trafficMutex = &sync.Mutex{}
 }
 
 func makeTrafficReport(ti TrafficInfo) {
@@ -113,7 +119,6 @@ func makeTrafficReport(ti TrafficInfo) {
 	msg[9] = tmp[1]  // Longitude.
 	msg[10] = tmp[2] // Longitude.
 
-
 	//Altitude: OK
 	//TODO: 0xFFF "invalid altitude."
 	alt := uint16(ti.alt)
@@ -146,7 +151,6 @@ func makeTrafficReport(ti TrafficInfo) {
 	sendMsg(prepareMessage(msg))
 }
 
-
 func parseDownlinkReport(s string) {
 	var ti TrafficInfo
 	s = s[1:]
@@ -282,5 +286,75 @@ func parseDownlinkReport(s string) {
 
 	ti.last_seen = time.Now()
 
+	trafficMutex.Lock()
 	traffic[ti.icao_addr] = ti
+	trafficMutex.Unlock()
 }
+
+//TODO
+/*
+//	dump1090Addr    = "127.0.0.1:30003"
+inConn, err := net.Dial("tcp", dump1090Addr)
+if err != nil {
+	time.Sleep(1 * time.Second)
+	continue
+}
+rdr := bufio.NewReader(inConn)
+for {
+	buf, err := rdr.ReadString('\n')
+	if err != nil { // Must have disconnected?
+		break
+	}
+	buf = strings.Trim(buf, "\r\n")
+	//log.Printf("%s\n", buf)
+	x := strings.Split(buf, ",")
+	//TODO: Add more sophisticated stuff that combines heading/speed updates with the location.
+	if len(x) < 22 {
+		continue
+	}
+	icao := x[4]
+	icaoDec, err := strconv.ParseInt(icao, 16, 32)
+	if err != nil {
+		continue
+	}
+	mutex.Lock()
+	// Retrieve previous information on this ICAO code.
+	var pi PositionInfo
+	if _, ok := blips[icaoDec]; ok {
+		pi = blips[icaoDec]
+	}
+
+	if x[1] == "3" {
+		//MSG,3,111,11111,AC2BB7,111111,2015/07/28,03:59:12.363,2015/07/28,03:59:12.353,,5550,,,42.35847,-83.42212,,,,,,0
+		alt := x[11]
+		lat := x[14]
+		lng := x[15]
+
+		//log.Printf("icao=%s, icaoDec=%d, alt=%s, lat=%s, lng=%s\n", icao, icaoDec, alt, lat, lng)
+		pi.alt = alt
+		pi.lat = lat
+		pi.lng = lng
+	}
+	if x[1] == "4" {
+		// MSG,4,111,11111,A3B557,111111,2015/07/28,06:13:36.417,2015/07/28,06:13:36.398,,,414,278,,,-64,,,,,0
+		vel := x[12]
+		hdg := x[13]
+		vr := x[16]
+
+		//log.Printf("icao=%s, icaoDec=%d, vel=%s, hdg=%s, vr=%s\n", icao, icaoDec, vel, hdg, vr)
+		pi.vel = vel
+		pi.hdg = hdg
+		pi.vr = vr
+	}
+	if x[1] == "1" {
+		// MSG,1,,,%02X%02X%02X,,,,,,%s,,,,,,,,0,0,0,0
+		tail := x[10]
+		pi.tail = tail
+	}
+
+	// Update "last seen" (any type of message).
+	pi.last_seen = time.Now()
+
+	blips[icaoDec] = pi // Update information on this ICAO code.
+	mutex.Unlock()
+*/