From 51bfbc964e778fd0fb00562931ca51c53946f5c7 Mon Sep 17 00:00:00 2001
From: Jonathan White <support@dmapps.us>
Date: Tue, 24 May 2016 02:12:33 -0400
Subject: [PATCH] Fix IPv6 support and warn when binding fails

Thanks to @eugenesan
---
 src/http/Server.cpp | 67 +++++++++++++++++++++++++++------------------
 1 file changed, 41 insertions(+), 26 deletions(-)

diff --git a/src/http/Server.cpp b/src/http/Server.cpp
index e54a9995..53261aed 100644
--- a/src/http/Server.cpp
+++ b/src/http/Server.cpp
@@ -323,16 +323,18 @@ void Server::request_completed(void *, struct MHD_Connection *,
 
 void Server::start(void)
 {
-    if (m_started) return;
+    bool nohost = true;
+    struct sockaddr_in6 as;
+    struct sockaddr_in6 *ss = &as;
+
+    if (m_started)
+        return;
 
     int port = HttpSettings::httpPort();
 
-    struct sockaddr_in as;
-    struct sockaddr_in *ss = &as;
-    bool nohost = true;
-
     QHostInfo info = QHostInfo::fromName(HttpSettings::httpHost());
     if (!info.addresses().isEmpty()) {
+        unsigned int flags = MHD_USE_SELECT_INTERNALLY;
         QHostAddress address = info.addresses().first();
 
         if (address.protocol() == QAbstractSocket::IPv4Protocol) {
@@ -342,32 +344,45 @@ void Server::start(void)
             addr->sin_port = htons(HttpSettings::httpPort());
             addr->sin_addr.s_addr = htonl(address.toIPv4Address());
             nohost = false;
-#ifdef MHD_USE_IPv6
-        } else {
-            struct sockaddr_in6* addr = (sockaddr_in6*)ss;
-            memset(addr, 0, sizeof(struct sockaddr_in6));
-            addr->sin6_family = AF_INET6;
-            addr->sin6_port = htons(HttpSettings::httpPort());
-            memcpy(&addr->sin6_addr, address.toIPv6Address().c, 16);
-            nohost = false;
-#endif
+        } else if (MHD_YES == MHD_is_feature_supported(MHD_FEATURE_IPv6)) {
+             struct sockaddr_in6* addr = (struct sockaddr_in6*)ss;
+             memset(addr, 0, sizeof(struct sockaddr_in6));
+             addr->sin6_family = AF_INET6;
+             addr->sin6_port = htons(HttpSettings::httpPort());
+             memcpy(&addr->sin6_addr, address.toIPv6Address().c, 16);
+             nohost = false;
+             flags |= MHD_USE_IPv6;
         }
 
-        daemon = MHD_start_daemon(MHD_USE_SELECT_INTERNALLY, port, NULL, NULL,
-                                 &this->request_handler_wrapper, this,
-                                 MHD_OPTION_NOTIFY_COMPLETED,
-                                 this->request_completed, NULL,
-                                 MHD_OPTION_SOCK_ADDR,
-                                 ss,
-                                 MHD_OPTION_END);
+        if (nohost) {
+             qWarning("HTTPPlugin: Faled to get configured host!");
+        } else {
+            if (NULL == (daemon = MHD_start_daemon(flags, port, NULL, NULL,
+                                            &this->request_handler_wrapper, this,
+                                            MHD_OPTION_NOTIFY_COMPLETED,
+                                            this->request_completed, NULL,
+                                            MHD_OPTION_SOCK_ADDR,
+                                            ss,
+                                            MHD_OPTION_END))) {
+                nohost = true;
+                qWarning("HTTPPlugin: Failed to bind to configured host!");
+            } else {
+                nohost = false;
+                //qWarning("HTTPPlugin: Binded to configured host.");
+            }
+        }
     }
 
     if (nohost) {
-        daemon = MHD_start_daemon(MHD_USE_SELECT_INTERNALLY, port, NULL, NULL,
-                                 &this->request_handler_wrapper, this,
-                                 MHD_OPTION_NOTIFY_COMPLETED,
-                                 this->request_completed, NULL,
-                                 MHD_OPTION_END);
+        if (NULL == (daemon = MHD_start_daemon(MHD_USE_SELECT_INTERNALLY, port, NULL, NULL,
+                                         &this->request_handler_wrapper, this,
+                                         MHD_OPTION_NOTIFY_COMPLETED,
+                                         this->request_completed, NULL,
+                                         MHD_OPTION_END))) {
+            qWarning("HTTPPlugin: Fatal! Failed to bind to both configured and default hosts!");                        
+        } else {
+            qWarning("HTTPPlugin: Bound to fallback address 0.0.0.0/:::!");
+        }
     }
 
     m_started = true;