File hostname-4.1.15.diff of Package pdns-recursor.openSUSE_Backports_SLE-15-SP1_Update

diff --git a/rec-carbon.cc b/rec-carbon.cc
index f8098edc7..3ffde2896 100644
--- a/rec-carbon.cc
+++ b/rec-carbon.cc
@@ -26,9 +26,11 @@ try
     return;
 
   if(hostname.empty()) {
-    char tmp[80];
+    char tmp[HOST_NAME_MAX+1];
     memset(tmp, 0, sizeof(tmp));
-    gethostname(tmp, sizeof(tmp));
+    if (gethostname(tmp, sizeof(tmp)) != 0) {
+      throw std::runtime_error("The 'carbon-ourname' setting has not been set and we are unable to determine the system's hostname: " + stringerror());
+    }
     char *p = strchr(tmp, '.');
     if(p) *p=0;