nixpkgs/pkgs/by-name/na/nanopb/test-simple-proto3/default.nix
Alexandros Liarokapis e36b4564d2 nanopb: 0.4.6 -> 0.4.8
This commit:
- Bumps the nanopb version
- Adds all runtime configuration options
- Implements proper cross-compilation support which is the main use-case of the library.
- Uses newer `finalAttrs` form of `mkDerivation` to allow for easier attribute overrides.

The cross-compilation support is achieved by splitting the package into two sub-packages
consisting of the build-time generator and the runtime library.

Nanopb explicitely supports this by providing specialized `GENERATOR` and
`RUNTIME` CMake configuration options.

The top-level package uses `propagatedNativeBuildInputs` and `propagatedBuildInputs` to propagate
the sub-packages and also adds convenient symlinks to make certain use cases easier.

== GENERATOR ==

The generator is a mostly ready-to-be-packaged python module tree.
We patch the library to also include the missing `__init__.py` and we
also fix the `PYTHON_INSTDIR` variable to follow best practice and to
prevent the library from attempting to install to a global directory.

We package the python module using `buildPythonPackage` and internally
override python in order to wrap the `nanopb_generator.py` executable.

We do *not* wrap `nanob_generator.py` due to it also being imported directly from python when
used through `protoc-gen-nanopb`.

== RUNTIME ==

The runtime is a simple library that consists of the common
functionality among generated headers/sources.

It is configured through `preprocessor definitions` and consumer projects *must*
be compiled with the same definitions.

This is currently achieved by exposing all configuration options through the top-level overrides and
patching the CMakeLists.txt so that the definitions are added to the to-be-installed
CMake targets as PUBLIC properties.
2024-06-26 22:15:27 +03:00

30 lines
979 B
Nix

{ lib, stdenv, nanopb }:
stdenv.mkDerivation {
name = "nanopb-test-simple-proto3";
meta.timeout = 60;
src = lib.fileset.toSource {
root = ./.;
fileset = lib.fileset.unions [ ./simple.proto ];
};
buildInputs = [ nanopb ];
# protoc requires any .proto file to be compiled to reside within it's
# proto_path. By default the current directory is automatically added to the
# proto_path. I tried using --proto_path ${./.} ${./simple.proto} and it did
# not work because they end up in the store at different locations.
dontInstall = true;
buildPhase = ''
mkdir $out
protoc --plugin=protoc-gen-nanopb=${nanopb}/bin/protoc-gen-nanopb --nanopb_out=$out simple.proto
'';
doCheck = true;
checkPhase = ''
grep -q SimpleMessage $out/simple.pb.c || (echo "ERROR: SimpleMessage not found in $out/simple.pb.c"; exit 1)
grep -q SimpleMessage $out/simple.pb.h || (echo "ERROR: SimpleMessage not found in $out/simple.pb.h"; exit 1)
'';
}