ntopng: fix build with rrdtool >= 1.9.0

pkgs/tools/networking/ntopng/default.nix

@@ -1,27 +1,29 @@
-{ lib
-, stdenv
-, autoreconfHook
-, curl
-, expat
-, fetchFromGitHub
-, git
-, json_c
-, libcap
-, libmaxminddb
-, libmysqlclient
-, libpcap
-, libsodium
-, ndpi
-, net-snmp
-, openssl
-, pkg-config
-, rdkafka
-, gtest
-, rrdtool
-, hiredis
-, sqlite
-, which
-, zeromq
+{
+  lib,
+  stdenv,
+  autoreconfHook,
+  curl,
+  expat,
+  fetchFromGitHub,
+  fetchpatch,
+  git,
+  json_c,
+  libcap,
+  libmaxminddb,
+  libmysqlclient,
+  libpcap,
+  libsodium,
+  ndpi,
+  net-snmp,
+  openssl,
+  pkg-config,
+  rdkafka,
+  gtest,
+  rrdtool,
+  hiredis,
+  sqlite,
+  which,
+  zeromq,
 }:
 
 stdenv.mkDerivation (finalAttrs: {
@@ -36,6 +38,11 @@ stdenv.mkDerivation (finalAttrs: {
     fetchSubmodules = true;
   };
 
+  patches = lib.optional (!lib.versionOlder rrdtool.version "1.9.0") (fetchpatch {
+    url = "https://github.com/ntop/ntopng/commit/5069aa4a6259bd0830a33f2ece980612dba5ace9.patch";
+    hash = "sha256-CnYzSE39J7pC2wHxp7Xst6g5pzQbpNUynJUVrTrtuOg=";
+  });
+
   preConfigure = ''
     substituteInPlace Makefile.in \
       --replace "/bin/rm" "rm"