chromium/components/metrics/generate_allowlist_from_histograms_file.gni

# Copyright 2023 The Chromium Authors
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

# Generates a C++ header file that contains a list of values under a specific variant
# or enum. The list can be used for ensuring that values in C++ are in sync with the
# histogram file. The header file provides a function to check if a value in is the list.
#
# Parameters:
#   input_xml_file: Input file that contains the allow list. This should be a
#     .xml file under path //tools/metrics/histograms/ or its subfolders.
#
#   namespace:
#     C++ namespace in which the generated code should be scoped.
#
#   tag:
#     XML tag that contains the values. Should be either "variant" or "enum".
#
#   allow_list_name:
#     Name of the variant or enum list in the histogram file.
#
#   output_file:
#     Name of the generated file to be used for checking if a value exists in the list.
#
template("generate_allowlist_from_histograms_file") {
  action(target_name) {
    output_file = "$target_gen_dir/" + invoker.output_file

    script =
        "//tools/metrics/histograms/generate_allowlist_from_histograms_file.py"
    outputs = [ output_file ]
    sources = [ invoker.input_xml_file ]

    args = [
      "--allow_list_name=" + invoker.allow_list_name,
      "--namespace=" + invoker.namespace,
      "--tag=" + invoker.tag,
      "--output_dir=" + rebase_path(root_gen_dir, root_build_dir),
      "--file=" + rebase_path(output_file, root_gen_dir),
      "--input=" + rebase_path(invoker.input_xml_file, root_build_dir),
    ]
  }
}