build/chip/chip_codegen.gni

# Copyright (c) 2022 Project CHIP Authors
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

import("//build_overrides/build.gni")
import("//build_overrides/chip.gni")
import("//build_overrides/pigweed.gni")

import("$dir_pw_build/python.gni")

# Defines a target that runs code generation based on
# scripts/codegen.py
#
# Arguments:
#   input
#     The ".matter" file to use to start the code generation
#
#   generator
#     Name of the generator to use (e.g. java, cpp-app)
#
#   outputs
#     Explicit names of the expected outputs. Enforced to validate that
#     expected outputs are generated when processing input files.
#
# NOTE: content of "outputs" is verified to match the output of codegen.py
#       exactly. It is not inferred on purpose, to make build-rules explicit
#       and verifiable (even though codege.py can at runtime report its outputs)
#
#       To find the list of generated files, you can run codegen.py with the
#       "--name-only" argument
#
# Example usage:
#
#  chip_codegen("java-jni-generate") {
#    input = "controller-clusters.matter"
#    generator = "java"
#
#    outputs = [
#       "jni/IdentifyClient-ReadImpl.cpp",
#       "jni/IdentifyClient-InvokeSubscribeImpl.cpp",
#       # ... more to follow
#    ]
#  }
#
template("chip_codegen") {
  _name = target_name
  _generator = invoker.generator

  config("${_name}_config") {
    include_dirs = [ target_gen_dir ]
  }

  pw_python_action(_name) {
    script = "${chip_root}/scripts/codegen.py"

    _idl_file = invoker.input
    _expected_outputs = "${target_gen_dir}/${_name}.expected.outputs"

    write_file(_expected_outputs, invoker.outputs, "list lines")

    args = [
      "--generator",
      _generator,
      "--output-dir",
      rebase_path(target_gen_dir, root_build_dir),
      "--expected-outputs",
      rebase_path(_expected_outputs, root_build_dir),
      rebase_path(_idl_file, root_build_dir),
    ]

    deps = [ "${chip_root}/scripts/idl" ]
    public_configs = [ ":${_name}_config" ]

    inputs = [
      _idl_file,
      _expected_outputs,
    ]
    sources = [ _idl_file ]

    outputs = []
    foreach(name, invoker.outputs) {
      outputs += [ "${target_gen_dir}/${name}" ]
    }
  }
}