third_party.pigweed.src/pw_build/target_config.bzl
Nathaniel Brough fc95cca6b3 workspace: Adds support for Bazel facades/backends
This makes use of Bazel's configuration feature 'label_flag' to create
a set of configurations that have overridable defaults from the command
line.

No-Docs-Update-Reason: Docs further up the stack in 41561.
Change-Id: Id4064c8f11bc6ec468aad18ef4d02fa472fdc590
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/41560
Reviewed-by: Keir Mierle <keir@google.com>
Reviewed-by: Ewout van Bekkum <ewout@google.com>
Reviewed-by: Akira Baruah <akirabaruah@google.com>
Commit-Queue: Keir Mierle <keir@google.com>
2021-04-30 20:27:07 +00:00

60 lines
2.1 KiB
Python

# Copyright 2021 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.
def _pigweed_config_impl(repository_ctx):
if repository_ctx.attr.build_file_content and \
repository_ctx.attr.build_file:
fail("Attributes 'build_file_content' and 'build_file' cannot both be \
defined at the same time.")
if not repository_ctx.attr.build_file_content and \
not repository_ctx.attr.build_file:
fail("Either 'build_file_content' or 'build_file' must be defined.")
if repository_ctx.name != "pigweed_config":
fail("This repository should be name 'pigweed_config'")
if repository_ctx.attr.build_file_content:
repository_ctx.file("BUILD", repository_ctx.attr.build_file_content)
if repository_ctx.attr.build_file:
repository_ctx.template("BUILD", repository_ctx.attr.build_file, {})
pigweed_config = repository_rule(
_pigweed_config_impl,
attrs = {
"build_file_content": attr.string(
doc = "The build file content to configure Pigweed.",
mandatory = False,
default = "",
),
"build_file": attr.label(
doc = "The label for the Pigweed config build file to use.",
mandatory = False,
default = "@pigweed//targets/host:host_config.BUILD",
),
},
doc = """
Configure Pigweeds backend implementations.
Example:
# WORKSPACE
pigweed_config(
# This must use the exact name specified here otherwise this
# remote repository will not function as expected.
name = "pigweed_config",
build_file = "//path/to/config.BUILD",
)
""",
)