Create helper to build the ebpf programs

dropworld/default.nix

@@ -1,16 +0,0 @@
-{clangStdenv, libbpf, ...}: clangStdenv.mkDerivation {
-  name = "dropworld";
-  src = ./.;
-  hardeningDisable = [ "stackprotector" "zerocallusedregs" ];
-  dontFixup = true;
-  buildInputs = [ libbpf ];
-
-  buildPhase = ''
-    clang -O2 -target bpf -g -c dropworld.c -o dropworld.o
-  '';
-
-  installPhase = ''
-    mkdir $out
-    cp dropworld.o $out
-  '';
-}

flake.nix

@@ -1,5 +1,5 @@
 {
-  description = "A very basic flake";
+  description = "eBPF sandbox";
 
   inputs = {
     nixpkgs.url = "github:nixos/nixpkgs?ref=nixos-unstable";
@@ -9,11 +9,23 @@
   outputs = inputs: inputs.flake-utils.lib.eachDefaultSystem (system:
     let
       pkgs = inputs.nixpkgs.legacyPackages.${system};
+
+      mkEbpfProg = name: src: pkgs.clangStdenv.mkDerivation {
+        name = "ebpf-${name}";
+        inherit src;
+        hardeningDisable = [ "stackprotector" "zerocallusedregs" ];
+        dontFixup = true;
+        buildInputs = with pkgs; [ libbpf ];
+
+        buildPhase = ''
+          clang -O2 -target bpf -g -c ${src}/main.c -o $out
+        '';
+      };
     in
     {
       packages = {
-        dropworld = pkgs.callPackage ./dropworld {};
-        tcpfilter = pkgs.callPackage ./tcpfilter {};
+        dropworld = mkEbpfProg "dropworld" ./dropworld;
+        tcpfilter = mkEbpfProg "tcpfilter" ./tcpfilter;
       };
 
       devShells.default = pkgs.mkShell {

tcpfilter/default.nix

@@ -1,16 +0,0 @@
-{clangStdenv, libbpf, ...}: clangStdenv.mkDerivation {
-  name = "tcpfilter";
-  src = ./.;
-  hardeningDisable = [ "stackprotector" "zerocallusedregs" ];
-  dontFixup = true;
-  buildInputs = [ libbpf ];
-
-  buildPhase = ''
-    clang -O2 -target bpf -g -c tcpfilter.c -o tcpfilter.o
-  '';
-
-  installPhase = ''
-    mkdir $out
-    cp tcpfilter.o $out
-  '';
-}