commit 781f3355bf1c0ba20748500385cce10d9629d0a9
author William A. Kennington III <wak@google.com> Fri Feb 01 21:07:10 2019 -0800
committer William A. Kennington III <wak@google.com> Thu Feb 14 12:10:12 2019 -0800
tree dac0fc6b9a4fbe38693146ab998a0f1e3da58c64
parent d2d05940681fe3ca960638c924e886474c77ed69

ethernet_interface: Only write Gateway= lines when present

This doesn't affect the total system behavior but it cleans up error
output from systemd-networkd which doesn't like empty Gateway= lines
when we don't have a set gateway.

Tested:
    Set the system to a static configuration with no gateway configured
    and saw that the line was no longer written. Configured a gateway
    and the line is written as expected.

Change-Id: I1ff9c4f564fab54d0c54e3f87fcd50b623f0fbda
Signed-off-by: William A. Kennington III <wak@google.com>

ethernet_interface.cpp

diff --git a/ethernet_interface.cpp b/ethernet_interface.cpp
index e7da8ff..4825e5b 100644
--- a/ethernet_interface.cpp
+++ b/ethernet_interface.cpp
@@ -568,8 +568,11 @@
 
         if (manager.getSystemConf())
         {
-            stream << "Gateway=" << manager.getSystemConf()->defaultGateway()
-                   << "\n";
+            const auto& gateway = manager.getSystemConf()->defaultGateway();
+            if (!gateway.empty())
+            {
+                stream << "Gateway=" << gateway << "\n";
+            }
         }
 
         // write the route section