tvheadend: include dtv scan tables

pkgs/servers/tvheadend/default.nix

@@ -1,10 +1,22 @@
 { stdenv, fetchFromGitHub, cmake, makeWrapper, pkgconfig
 , avahi, dbus, gettext, git, gnutar, gzip, bzip2, ffmpeg_3, libiconv, openssl, python
-, which, zlib }:
+, v4l-utils, which, zlib }:
 
 let
   version = "4.2.8";
 
+  dtv-scan-tables = stdenv.mkDerivation {
+    pname = "dtv-scan-tables";
+    version = "2020-05-18";
+    src = fetchFromGitHub {
+      owner = "tvheadend";
+      repo = "dtv-scan-tables";
+      rev = "e3138a506a064f6dfd0639d69f383e8e576609da";
+      sha256 = "19ac9ds3rfc2xrqcywsbd1iwcpv7vmql7gp01iikxkzcgm2g2b6w";
+    };
+    nativeBuildInputs = [ v4l-utils ];
+    installFlags = [ "DATADIR=$(out)" ];
+  };
 in stdenv.mkDerivation {
   pname = "tvheadend";
   inherit version;
@@ -28,7 +40,7 @@ in stdenv.mkDerivation {
   NIX_CFLAGS_COMPILE = [ "-Wno-error=format-truncation" "-Wno-error=stringop-truncation" ];
 
   # disable dvbscan, as having it enabled causes a network download which
-  # cannot happen during build.
+  # cannot happen during build.  We now include the dtv-scan-tables ourselves
   configureFlags = [
     "--disable-dvbscan"
     "--disable-bintray_cache"
@@ -45,6 +57,9 @@ in stdenv.mkDerivation {
     substituteInPlace src/config.c \
       --replace /usr/bin/tar ${gnutar}/bin/tar
 
+    substituteInPlace src/input/mpegts/scanfile.c \
+      --replace /usr/share/dvb ${dtv-scan-tables}/dvbv5
+
     # the version detection script `support/version` reads this file if it
     # exists, so let's just use that
     echo ${version} > rpm/version