From 458f9f42d37117e7ba3be83f9bc759f3630a0887 Mon Sep 17 00:00:00 2001
From: Felix Kauselmann <2039670+selmf@users.noreply.github.com>
Date: Fri, 8 Aug 2014 21:19:56 +0200
Subject: [PATCH] Fix for Issue #18 Linux: YACReaderLibrary segfaults on start
 if an openvpn connection is present

---
 YACReaderLibrary/server_config_dialog.cpp | 32 ++++++++++++-----------
 1 file changed, 17 insertions(+), 15 deletions(-)

diff --git a/YACReaderLibrary/server_config_dialog.cpp b/YACReaderLibrary/server_config_dialog.cpp
index 571dcc7f..0865e89b 100644
--- a/YACReaderLibrary/server_config_dialog.cpp
+++ b/YACReaderLibrary/server_config_dialog.cpp
@@ -31,21 +31,23 @@ QList<QString> addresses()
 	getifaddrs(&ifAddrStruct);
 
 	for (ifa = ifAddrStruct; ifa != NULL; ifa = ifa->ifa_next) {
-		if (ifa ->ifa_addr->sa_family==AF_INET) { // check it is IP4
-			// is a valid IP4 Address
-			tmpAddrPtr=&((struct sockaddr_in *)ifa->ifa_addr)->sin_addr;
-			char addressBuffer[INET_ADDRSTRLEN];
-			inet_ntop(AF_INET, tmpAddrPtr, addressBuffer, INET_ADDRSTRLEN);
-			QString add(addressBuffer);
-			localAddreses.push_back(QString(addressBuffer));
-			//printf("%s IP Address %s\n", ifa->ifa_name, addressBuffer); 
-		} else if (ifa->ifa_addr->sa_family==AF_INET6) { // check it is IP6
-			// is a valid IP6 Address
-			tmpAddrPtr=&((struct sockaddr_in6 *)ifa->ifa_addr)->sin6_addr;
-			char addressBuffer[INET6_ADDRSTRLEN];
-			inet_ntop(AF_INET6, tmpAddrPtr, addressBuffer, INET6_ADDRSTRLEN);
-			//printf("%s IP Address %s\n", ifa->ifa_name, addressBuffer); 
-		} 
+		if (ifa ->ifa_addr) {
+			if (ifa ->ifa_addr->sa_family==AF_INET) { // check it is IP4
+				// is a valid IP4 Address
+				tmpAddrPtr=&((struct sockaddr_in *)ifa->ifa_addr)->sin_addr;
+				char addressBuffer[INET_ADDRSTRLEN];
+				inet_ntop(AF_INET, tmpAddrPtr, addressBuffer, INET_ADDRSTRLEN);
+				QString add(addressBuffer);
+				localAddreses.push_back(QString(addressBuffer));
+				//printf("%s IP Address %s\n", ifa->ifa_name, addressBuffer); 
+			} else if (ifa->ifa_addr->sa_family==AF_INET6) { // check it is IP6
+				// is a valid IP6 Address
+				tmpAddrPtr=&((struct sockaddr_in6 *)ifa->ifa_addr)->sin6_addr;
+				char addressBuffer[INET6_ADDRSTRLEN];
+				inet_ntop(AF_INET6, tmpAddrPtr, addressBuffer, INET6_ADDRSTRLEN);
+				//printf("%s IP Address %s\n", ifa->ifa_name, addressBuffer); 
+			} 
+		}
 	}
 	if (ifAddrStruct!=NULL) freeifaddrs(ifAddrStruct);
 	return localAddreses;