Automatically determine most suitable local IP to talk to ambed

scripts/xlxd

@@ -20,8 +20,6 @@ PATH=/sbin:/bin:/usr/sbin:/usr/bin
 NAME="xlxd"
 DAEMON="/xlxd/xlxd"
 ARGUMENTS="XLX999 192.168.1.240 127.0.0.1"
-#Case where ambed runs on another host and you want to use another IP to talk to it. Here ambed is on 10.9.0.100 and 10.9.0.1 is used to talk to it
-#ARGUMENTS="XLX999 192.168.1.240 10.9.0.100 10.9.0.1
 PIDFILE="/var/log/xlxd.pid"
 USER=root
 GROUP=root

src/ccodecstream.cpp

@@ -99,7 +99,7 @@ bool CCodecStream::Init(uint16 uiPort)
     m_uiPort = uiPort;
     
     // create our socket
-    ok = m_Socket.Open(CIp("0.0.0.0"), uiPort);
+    ok = m_Socket.Open(g_Reflector.GetTranscoderLocalIp(), uiPort);
     if ( ok )
     {
         // start  thread;

src/cip.cpp

@@ -3,7 +3,7 @@
 //  xlxd
 //
 //  Created by Jean-Luc Deltombe (LX3JL) on 31/10/2015.
-//  Copyright © 2015 Jean-Luc Deltombe (LX3JL). All rights reserved.
+//  Copyright © 2015 Jean-Luc Deltombe (LX3JL). All rights reremoteed.
 //
 // ----------------------------------------------------------------------------
 //    This file is part of xlxd.
@@ -24,6 +24,7 @@
 
 #include "main.h"
 #include <string.h>
+#include <unistd.h>
 #include "cip.h"
 
 #include <netdb.h>
@@ -88,4 +89,49 @@ CIp::operator const char *() const
     return ::inet_ntoa(m_Addr.sin_addr);
 }
 
+////////////////////////////////////////////////////////////////////////////////////////
+// operator
+void CIp::GetLocalIp(const CIp & remoteIp, const CIp & defaultLocalIp, CIp & localIp)
+{
+    localIp = CIp(defaultLocalIp);
+    int remotePort = 10100;
+
+    struct sockaddr_in remote;
+    int sock = socket(AF_INET, SOCK_DGRAM, 0);
+
+    //Socket could not be created
+    if(sock < 0)
+    {
+        std::cout << "Socket error" << std::endl;
+    }
+
+    memset(&remote, 0, sizeof(remote));
+    remote.sin_family = AF_INET;
+    remote.sin_addr.s_addr = remoteIp.m_Addr.sin_addr.s_addr;
+    remote.sin_port = htons(remotePort);
+
+    int err = connect(sock, (const struct sockaddr*)&remote, sizeof(remote));
+    if (err < 0)
+    {
+        std::cout << "Error number: " << errno
+            << ". Error message: " << strerror(errno) << std::endl;
+    }
+
+    struct sockaddr_in name;
+    socklen_t namelen = sizeof(name);
+    err = ::getsockname(sock, (struct sockaddr*)&name, &namelen);
 
+    char buffer[80];
+    const char* p = inet_ntop(AF_INET, &name.sin_addr, buffer, 80);
+    if(p != NULL)
+    {
+        localIp = CIp(&name);
+        //std::cout << "Local IP address for " <<  remoteIp << " is: " << buffer << std::endl;
+    }
+    else
+    {
+        //std::cout << "Error number: " << errno << ". Error message: " << strerror(errno) << std::endl;
+    }
+
+    ::close(sock);
+}

src/cip.h

@@ -53,6 +53,9 @@ public:
     // operator
     bool operator ==(const CIp &) const;
     operator const char *() const;
+
+    // Factory
+    static void GetLocalIp(const CIp & remoteIp, const CIp & defaultLocalIp, CIp & localIp);
     
 protected:
     // data

src/creflector.h

@@ -59,8 +59,10 @@ public:
     const CCallsign &GetCallsign(void) const        { return m_Callsign; }
     void SetListenIp(const CIp &ip)                 { m_Ip = ip; }
     void SetTranscoderIp(const CIp &ip)             { m_AmbedIp = ip; }
+    void SetTranscoderLocalIp(const CIp &ip)        { m_AmbedLocalIp = ip; }
     const CIp &GetListenIp(void) const              { return m_Ip; }
     const CIp &GetTranscoderIp(void) const          { return m_AmbedIp; }
+    const CIp &GetTranscoderLocalIp(void) const     { return m_AmbedLocalIp; }
     
     // operation
     bool Start(void);
@@ -121,6 +123,7 @@ protected:
     CCallsign       m_Callsign;
     CIp             m_Ip;
     CIp             m_AmbedIp;
+    CIp             m_AmbedLocalIp;
     
     // objects
     CUsers          m_Users;            // sorted list of lastheard stations

src/ctranscoder.cpp

@@ -97,7 +97,7 @@ bool CTranscoder::Init(void)
     m_Ip = g_Reflector.GetTranscoderIp();
     
     // create our socket
-    ok = m_Socket.Open(CIp("0.0.0.0"), TRANSCODER_PORT);
+    ok = m_Socket.Open(g_Reflector.GetTranscoderLocalIp(), TRANSCODER_PORT);
     if ( ok )
     {
         // start  thread;

src/main.cpp

@@ -99,8 +99,19 @@ int main(int argc, const char * argv[])
 
     // initialize reflector
     g_Reflector.SetCallsign(argv[1]);
-    g_Reflector.SetListenIp(CIp(argv[2]));
-    g_Reflector.SetTranscoderIp(CIp(CIp(argv[3])));
+
+    CIp listenIp = CIp(argv[2]);
+    CIp localTranscoderIp = CIp(listenIp);
+    CIp transcoderIp = CIp(argv[3]);
+
+    if(transcoderIp.GetAddr() != CIp("127.0.0.1").GetAddr())
+    {
+        CIp::GetLocalIp(transcoderIp, listenIp, localTranscoderIp);
+    }
+
+    g_Reflector.SetListenIp(listenIp);
+    g_Reflector.SetTranscoderIp(transcoderIp);
+    g_Reflector.SetTranscoderLocalIp(localTranscoderIp);
   
     // and let it run
     if ( !g_Reflector.Start() )
@@ -109,7 +120,9 @@ int main(int argc, const char * argv[])
         exit(EXIT_FAILURE);
     }
     std::cout << "Reflector " << g_Reflector.GetCallsign()
-              << "started and listening on " << g_Reflector.GetListenIp() << std::endl;
+              << "started and listening on " << g_Reflector.GetListenIp() << std::endl
+              << "Listening for ambed " << g_Reflector.GetTranscoderIp()
+              << " on " << g_Reflector.GetTranscoderLocalIp() << std::endl;
     
 #ifdef RUN_AS_DAEMON
 	// run forever