pw_build/copy_and_patch.gni

# Copyright 2024 The Pigweed 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
#
#     https://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("python_action.gni")
import("target_types.gni")

# Applies a patch to a copy of file.  The source file will not be patched in place,
# but instead copied before patching.
# The output of this target will be the patched file.
#
# Args:
#   source: (required) The source file to be patched.
#   out: (required) The output file containing the patched contents. This value
#                   can not be the same as the source value.
#   patch_file: (required) The patch file.
#   root: (optional) The root directory for applying the path.

template("pw_copy_and_patch_file") {
  assert(defined(invoker.source), "'source' must be provided")
  assert(defined(invoker.out), "'out' must be provided")
  assert(defined(invoker.patch_file), "'patch_file' must be provided")

  _src_file = rebase_path(invoker.source, root_build_dir)
  _out_file = "${target_gen_dir}/${invoker.out}"
  _out_relative = rebase_path(_out_file, root_build_dir)
  _patch_file = rebase_path(invoker.patch_file, root_build_dir)

  _args = [
    "--patch-file=${_patch_file}",
    "--src=${_src_file}",
    "--dst=${_out_relative}",
  ]

  if (defined(invoker.root)) {
    _args += [
      "--root",
      rebase_path(invoker.root, root_build_dir),
    ]
  }

  pw_python_action(target_name) {
    module = "pw_build.copy_and_patch"
    inputs = [
      invoker.patch_file,
      invoker.source,
    ]
    args = _args
    outputs = [ _out_file ]
    python_deps = [ "$dir_pw_build/py" ]
  }
}