Fix/ForeFlight: Send unicast to many clients, closes #221

Data/ForeFlight/ForeFlight_Sim.py

@@ -0,0 +1,35 @@
+#!/usr/bin/python3
+# Miniature mock-up of interface to ForeFlight
+# - Every 5s broadcasts the message {"App":"ForeFlight","GDL90":{"port":4000, "sim":true}} on port 63093
+# - Listens on UDP Port 49002 and outputs whatever it receives
+
+import sys
+import socket
+import time
+
+#--- Output Socket (Broadcast)
+sockBcst = socket.socket(socket.AF_INET, socket.SOCK_DGRAM, socket.IPPROTO_UDP)
+sockBcst.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, 1)
+
+#--- Listen Socket
+sockListen = socket.socket(socket.AF_INET, socket.SOCK_DGRAM, socket.IPPROTO_UDP)
+sockListen.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
+if sys.platform != "win32":
+	sockListen.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEPORT, 1)
+sockListen.settimeout(1.0)
+sockListen.bind(('', 49002))
+
+#---wait for and print data
+tsNextBcst = 0.0
+while 1:
+    # Every (about) 5s we broadcast our availability to the world
+    if (time.monotonic() > tsNextBcst):
+        sockBcst.sendto(b'{"App":"ForeFlight","GDL90":{"port":4000, "sim":true}}', ('<broadcast>', 63093))
+        tsNextBcst = time.monotonic() + 5.0
+    # Wait for data, timeout is defined about (1s) and would throw an exception
+    try:
+        data, addr = sockListen.recvfrom(1024)
+        print(time.strftime('%H:%M:%S'), addr)
+        print(data.decode("utf-8"))
+    except OSError:
+         pass

Data/RealTraffic/udp_send.py

@@ -1,14 +1,26 @@
-#!/usr/bin/python
+#!/usr/bin/python3
 
+import sys
 import socket
 
-UDP_IP = "localhost"
-UDP_PORT = 49003
+if len(sys.argv) < 3:
+    print ("Usage: udp_send.py <TargetHost> <Port> [msg]")
+    exit(1)
+
+UDP_IP = sys.argv[1] # "localhost"
+UDP_PORT = int(sys.argv[2]) # 49003
 MESSAGE = "Hello, World!"
+if len(sys.argv) >= 4:
+    MESSAGE = sys.argv[3]
 
-print "UDP target IP:", UDP_IP
-print "UDP target port:", UDP_PORT
-print "message:", MESSAGE
+print ("UDP target IP:", UDP_IP)
+print ("UDP target port:", UDP_PORT)
+print ("message:", MESSAGE)
 
 sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM, socket.IPPROTO_UDP) # UDP
+
+# User wants broadcast? We can do that!
+if UDP_IP == '255.255.255.255':
+    sock.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, 1)
+
 sock.sendto(MESSAGE.encode('utf-8'), (UDP_IP, UDP_PORT))

Include/LTForeFlight.h

@@ -40,7 +40,6 @@
 #define FF_CHECK_POPUP          "Open ForeFlight's web site about the Mobile EFB"
 
 #define FOREFLIGHT_NAME        "ForeFlight"
-#define FF_LOCALHOST            "0.0.0.0"
 constexpr size_t FF_NET_BUF_SIZE    = 512;
 
 // sending intervals in milliseonds
@@ -50,6 +49,7 @@ constexpr std::chrono::milliseconds FF_INTVL        = std::chrono::milliseconds(
 
 #define MSG_FF_LISTENING        "ForeFlight: Waiting for a ForeFlight device to broadcast its address..."
 #define MSG_FF_SENDING          "ForeFlight: Starting to send to %s"
+#define MSG_FF_NOT_SENDING      "ForeFlight: No longer sending to %s"
 #define MSG_FF_STOPPED          "ForeFlight: Stopped"
 
 //
@@ -64,13 +64,9 @@ class ForeFlightSender : public LTOutputChannel
         FF_STATE_DISCOVERY,             ///< Waiting for a ForeFlight device to broadcast its address on the network
         FF_STATE_SENDING,               ///< Actually sending data to a discovered device
     } state = FF_STATE_NONE;
-    std::string ffAddr;                 ///< Address of the ForeFlight app we are sending to
-    XPMP2::UDPReceiver udp;             ///< UDP socket for receiving and sending UDP datagrams from/to ForeFlight
-    // time points last sent something
-    std::chrono::steady_clock::time_point nextGPS;
-    std::chrono::steady_clock::time_point nextAtt;
-    std::chrono::steady_clock::time_point nextTraffic;
-    std::chrono::steady_clock::time_point lastStartOfTraffic;
+    std::string ffAddr;                 ///< Addresses of the ForeFlight apps we are sending to
+    /// UDP sockets for sending UDP datagrams from/to ForeFlight apps
+    std::map<XPMP2::SockAddrTy, XPMP2::UDPReceiver> mapUdp;
 
 public:
     ForeFlightSender ();