toolchains.py

#
# Copyright (C) 2020 The Android Open Source Project
#
# 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.
#
"""APIs for accessing toolchains."""

import functools
from pathlib import Path

from builder_registry import BuilderRegistry
import paths
import version

class Toolchain:
    """Base toolchain."""

    path: Path
    build_path: Path

    def __init__(self, path: Path, build_path: Path) -> None:
        self.path = path
        self.build_path = build_path

    @property
    def cc(self) -> Path:  # pylint: disable=invalid-name
        return self.path / 'bin' / 'clang'

    @property
    def cxx(self) -> Path:
        """Returns the path to c++ compiler."""
        return self.path / 'bin' / 'clang++'

    @property
    def lib_dir(self) -> Path:
        """Returns the path to lib dir."""
        return self.path / 'lib64'

    @property
    def _version_file(self) -> Path:
        return self.path / 'include' / 'clang' / 'Basic'/ 'Version.inc'

    @functools.cached_property
    def _version(self) -> version.Version:
        return version.Version(self._version_file)

    @property
    def clang_lib_dir(self) -> Path:
        return self.lib_dir / 'clang' / self._version.long_version()

    @property
    def resource_dir(self) -> Path:
        return self.clang_lib_dir / 'lib' / 'linux'


@functools.lru_cache
def _build_toolchain_for_path(path: Path, build_path: Path) -> Toolchain:
    """Returns a toolchain object for a given path."""
    return Toolchain(path, build_path)


def get_prebuilt_toolchain() -> Toolchain:
    """Returns the prebuilt toolchain."""
    # Prebuilt toolchain doesn't have a build path. Use a dummy path instead.
    return _build_toolchain_for_path(paths.CLANG_PREBUILT_DIR, Path('.'))


def get_toolchain_from_builder(builder) -> Toolchain:
    """Gets the toolchain from a toolchain builder."""
    return _build_toolchain_for_path(builder.install_dir, builder.output_dir)


def get_toolchain_by_name(name: str) -> Toolchain:
    """Tet a toolchain by name."""
    if name == 'prebuilt':
        return get_prebuilt_toolchain()
    return get_toolchain_from_builder(BuilderRegistry.get(name))


_RUNTIME_TOOLCHAIN: Toolchain = get_prebuilt_toolchain()
def set_runtime_toolchain(toolchain: Toolchain) -> None:
    """Sets the toolchain used to build runtime."""
    global _RUNTIME_TOOLCHAIN  # pylint: disable=global-statement
    _RUNTIME_TOOLCHAIN = toolchain


def get_runtime_toolchain() -> Toolchain:
    """Gets the toolchain used to build runtime."""
    global _RUNTIME_TOOLCHAIN  # pylint: disable=global-statement
    return _RUNTIME_TOOLCHAIN