identify and error on conflicting servertls directives on merged gemini servers

fixes #7

1 files changed, 7 insertions, 0 deletions

diff --git a/gemini.go b/gemini.go
index 975b62b..f48f3ac 100644
--- a/gemini.go
+++ b/gemini.go
@@ -59,9 +59,16 @@ func buildGeminiServers(servers []Server, config *Configuration) ([]sr.Server, e
 		}
 
 		var tlsConfig *tls.Config
+		var keyfile, certfile string
 		for _, config := range configs {
+			if (keyfile != "" && config.tlsKeyFile == keyfile) || (certfile != "" && config.tlsCertFile == certfile) {
+				return nil, errors.New("conflicting 'servertls' directives for gemini server")
+			}
+
 			if config.TLS != nil {
 				tlsConfig = config.TLS
+				keyfile = config.tlsKeyFile
+				certfile = config.tlsCertFile
 				break
 			}
 		}