Nix build system for ardupilot

Tools/flake.nix

@@ -0,0 +1,10 @@
+{
+  inputs = {
+    nixpkgs.url = "nixpkgs/nixos-unstable";
+    flake-utils.url = "github:numtide/flake-utils";
+  };
+  outputs = inputs@{ flake-utils, ... }:
+    flake-utils.lib.meld inputs [
+      ./nix
+    ];
+}

Tools/nix/ardupilot-firmware.nix

@@ -0,0 +1,57 @@
+{ self, flake-utils, nixpkgs, ... }:
+let supported-systems = with flake-utils.lib.system; [ x86_64-linux ];
+in flake-utils.lib.eachSystem supported-systems (system:
+  let
+    pkgs = import nixpkgs { inherit system; };
+    python = (pkgs.python39.withPackages
+      (ps: with ps; [ setuptools future pexpect empy ]));
+  in {
+    packages.ardupilot = pkgs.pkgsCross.arm-embedded.stdenv.mkDerivation {
+      name = "ardupilot";
+      src = builtins.fetchGit {
+        url = "https://github.com/ArduPilot/ardupilot.git";
+        rev = "df2be63e21217b626be53c7c9e98f37410b12126";
+        ref = "Rover-4.4";
+        submodules = true;
+      };
+      hardeningDisable = [ "all" ];
+      buildInputs = [ python pkgs.git pkgs.rsync pkgs.gcc ];
+      nativeBuildInputs = [
+        python
+        pkgs.git
+        pkgs.rsync
+        pkgs.gcc-arm-embedded
+        pkgs.gcc_multi
+        pkgs.wafHook
+      ];
+      patches = [
+        ./patches/ardusim_patches/runnable_status.patch
+        ./patches/ardusim_patches/remove_gcc_Werror.patch
+        ./patches/ardusim_patches/fake_git_rev.patch
+      ];
+      wafPath = "modules/waf/waf-light";
+      wafConfigureFlags = [ "--board CubeOrangePlus" ];
+      wafFlags = [ "rover" ];
+      postInstall = ''
+          cp -r build/CubeOrangePlus/bin/* $out/bin/.
+          '';
+      system = builtins.currentSystem;
+    };
+    packages.ardupilot-fw-flasher = pkgs.stdenv.mkDerivation {
+      name = "ardupilot-fw-flasher";
+      src = builtins.fetchGit {
+        url = "https://github.com/ArduPilot/ardupilot.git";
+        rev = "df2be63e21217b626be53c7c9e98f37410b12126";
+        ref = "Rover-4.4";
+        submodules = true;
+      };
+      dontBuild = true;
+
+      buildInputs = [ python ];
+
+      installPhase = ''
+        mkdir -p $out/bin
+        cp Tools/scripts/uploader.py $out/bin/ardupilot-fw-flasher
+      '';
+    };
+  })

Tools/nix/ardupilot-sim.nix

@@ -0,0 +1,39 @@
+{ self, flake-utils, nixpkgs, ... }:
+  let supported-systems = with flake-utils.lib.system; [
+    x86_64-linux
+    aarch64-linux
+    aarch64-darwin
+  ];
+in flake-utils.lib.eachSystem supported-systems (system:
+    let
+        pkgs = import nixpkgs { inherit system; };
+        inherit (pkgs) lib;
+        python = (pkgs.python39.withPackages
+        (ps: with ps; [ setuptools future pexpect empy ]));
+  in {
+    packages = flake-utils.lib.flattenTree {
+      ardusim = pkgs.stdenv.mkDerivation {
+        name = "ardusim";
+        src = builtins.fetchGit {
+          url = "https://github.com/ArduPilot/ardupilot.git";
+          rev = "df2be63e21217b626be53c7c9e98f37410b12126";
+          ref = "Rover-4.4";
+          submodules = true;
+        };
+        buildInputs = [ python pkgs.git pkgs.rsync pkgs.gcc ];
+
+        nativeBuildInputs = [ pkgs.wafHook ];
+        patches = [
+          ./patches/runnable_status.patch
+          ./patches/remove_gcc_Werror.patch
+          ./patches/fake_git_rev.patch
+        ];
+        wafPath = "modules/waf/waf-light";
+        wafConfigureFlags = [ "--board sitl" ];
+        wafFlags = [ "rover" ];
+        postInstall =
+          "	mv Tools/autotest/default_params/rover.parm $out/.;\n	mv Tools/mavproxy_modules/ $out/.;\n";
+        system = builtins.currentSystem;
+      };
+    };
+  })

Tools/nix/default.nix

@@ -0,0 +1,2 @@
+inputs@{ flake-utils, ... }:
+flake-utils.lib.meld inputs [ ./ardupilot-firmware.nix ./ardupilot-sim.nix] 

Tools/nix/patches/fake_git_rev.patch

@@ -0,0 +1,12 @@
+diff --git a/Tools/ardupilotwaf/git_submodule.py b/Tools/ardupilotwaf/git_submodule.py
+index be28216e9c..71ab1f9c33 100644
+--- a/Tools/ardupilotwaf/git_submodule.py
++++ b/Tools/ardupilotwaf/git_submodule.py
+@@ -157,6 +157,7 @@ def git_submodule_post_fun(bld):
+     bld.add_post_fun(_post_fun)
+
+ def _git_head_hash(ctx, path, short=False):
++    return "2388afcd"
+     cmd = [ctx.env.get_flat('GIT'), 'rev-parse']
+     if short:
+         cmd.append('--short=8')

Tools/nix/patches/remove_gcc_Werror.patch

@@ -0,0 +1,13 @@
+diff --git a/libraries/AP_Scripting/wscript b/libraries/AP_Scripting/wscript
+index 479fcfe387..f3eb39dcbd 100644
+--- a/libraries/AP_Scripting/wscript
++++ b/libraries/AP_Scripting/wscript
+@@ -8,7 +8,7 @@ from waflib.TaskGen import after_method, before_method, feature
+ import os
+
+ # these are only used for binding generation, not compilation of the library
+-BINDING_CFLAGS="-std=c99 -Wno-error=missing-field-initializers -Wall -Werror -Wextra"
++BINDING_CFLAGS="-std=c99 -Wno-error=missing-field-initializers -Wall -Wextra"
+ BINDING_CC="gcc"
+
+ def configure(cfg):

Tools/nix/patches/runnable_status.patch

@@ -0,0 +1,18 @@
+diff --git a/Tools/ardupilotwaf/git_submodule.py b/Tools/ardupilotwaf/git_submodule.py
+index be28216e9c..ee46c11185 100644
+--- a/Tools/ardupilotwaf/git_submodule.py
++++ b/Tools/ardupilotwaf/git_submodule.py
+@@ -69,11 +69,12 @@ class update_submodule(Task.Task):
+         return out.strip() == head
+
+     def runnable_status(self):
++        self.non_fast_forward = []
++        return Task.SKIP_ME
+         e = self.env.get_flat
+         cmd = e('GIT'), 'submodule', 'status', '--recursive', '--', e('SUBMODULE_PATH')
+         out = self.generator.bld.cmd_and_log(cmd, quiet=Context.BOTH, cwd=self.cwd)
+
+-        self.non_fast_forward = []
+
+         # git submodule status uses a blank prefix for submodules that are up
+         # to date

Tools/result

@@ -0,0 +1 @@
+/nix/store/qciia3l1kmjq5y8mdnsxqypxgqcgk9zs-ardusim

result

@@ -0,0 +1 @@
+/nix/store/48h7ymfg49vg29f1viamb17hkxqcg28s-ardusim