| #!/usr/bin/env python3 |
| # Copyright 2020 The IREE Authors |
| # |
| # Licensed under the Apache License v2.0 with LLVM Exceptions. |
| # See https://llvm.org/LICENSE.txt for license information. |
| # SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| """This script assists with converting from Bazel BUILD files to CMakeLists.txt. |
| |
| Bazel BUILD files should, where possible, be written to use simple features |
| that can be directly evaluated and avoid more advanced features like |
| variables, list comprehensions, etc. |
| |
| Generated CMake files will be similar in structure to their source BUILD |
| files by using the functions in build_tools/cmake/ that imitate corresponding |
| Bazel rules (e.g. cc_library -> iree_cc_library.cmake). |
| |
| Common usage: |
| Run across all default paths in the project (in .bazel_to_cmake.cfg.py): |
| $ python build_tools/bazel_to_cmake/bazel_to_cmake.py |
| |
| Run on an individual file: |
| $ python build_tools/bazel_to_cmake/bazel_to_cmake.py runtime/src/iree/base/BUILD.bazel |
| |
| Run on multiple files (e.g. as part of a pre-commit hook): |
| $ python build_tools/bazel_to_cmake/bazel_to_cmake.py runtime/src/iree/base/BUILD.bazel runtime/src/iree/vm/BUILD.bazel |
| |
| Run on a single directory: |
| $ python build_tools/bazel_to_cmake/bazel_to_cmake.py --dir runtime/src/iree/base/ |
| |
| Run on all files under a root directory: |
| $ python build_tools/bazel_to_cmake/bazel_to_cmake.py --root-dir runtime/src/iree/ |
| |
| Configuration |
| ------------- |
| When invoked, bazel_to_cmake will traverse up from the current directory until |
| it finds a ".bazel_to_cmake.cfg.py" file. This file both serves as a marker |
| for the repository root and provides repository specific configuration. |
| |
| The file is evaluated as a module and can have the following customizations: |
| |
| * DEFAULT_ROOT_DIRS: A list of root directory names that should be processed |
| (relative to the repository root) when invoked without a --repo_root or --dir. |
| * REPO_MAP: Mapping of canonical Bazel repo name (i.e. "@iree_core") to what it |
| is known as locally (most commonly the empty string). This is used in global |
| target rules to make sure that they work either in the defining or referencing |
| repository. |
| * CustomBuildFileFunctions: A class that extends |
| `bazel_to_cmake_converter.BuildFileFunctions` and injects globals for |
| processing the BUILD file. All symbols that do not start with "_" are |
| available. |
| * CustomTargetConverter: A class that extends |
| `bazel_to_cmake_targets.TargetConverter` and customizes target mapping. |
| Typically, this is used for purely local targets in leaf projects (as global |
| targets will be encoded in the main bazel_to_cmake_targets.py file). |
| """ |
| # pylint: disable=missing-docstring |
| |
| import argparse |
| import importlib |
| import importlib.util |
| import os |
| import re |
| import sys |
| import textwrap |
| from enum import Enum |
| from pathlib import Path |
| |
| import bazel_to_cmake_converter |
| |
| repo_root = None |
| repo_cfg = None |
| |
| EDIT_BLOCKING_PATTERN = re.compile( |
| r"bazel[\s_]*to[\s_]*cmake[\s_]*:?[\s_]*do[\s_]*not[\s_]*edit", flags=re.IGNORECASE |
| ) |
| |
| PRESERVE_ABOVE_TAG = "### BAZEL_TO_CMAKE_PRESERVES_ALL_CONTENT_ABOVE_THIS_LINE ###" |
| PRESERVE_BELOW_TAG = "### BAZEL_TO_CMAKE_PRESERVES_ALL_CONTENT_BELOW_THIS_LINE ###" |
| REPO_CFG_FILE = ".bazel_to_cmake.cfg.py" |
| REPO_CFG_MODULE_NAME = "bazel_to_cmake_repo_config" |
| |
| |
| class Status(Enum): |
| UPDATED = 1 |
| NOOP = 2 |
| FAILED = 3 |
| SKIPPED = 4 |
| NO_BUILD_FILE = 5 |
| |
| |
| def parse_arguments(): |
| parser = argparse.ArgumentParser(description="Bazel to CMake conversion helper.") |
| parser.add_argument( |
| "--preview", |
| help="Prints results instead of writing files", |
| action="store_true", |
| default=False, |
| ) |
| parser.add_argument( |
| "--allow_partial_conversion", |
| help="Generates partial files, ignoring errors during conversion.", |
| action="store_true", |
| default=False, |
| ) |
| parser.add_argument( |
| "--verbosity", |
| "-v", |
| type=int, |
| default=0, |
| help="Specify verbosity level where higher verbosity emits more logging." |
| " 0 (default): Only output errors and summary statistics." |
| " 1: Also output the name of each directory as it's being processed and" |
| " whether the directory is skipped." |
| " 2: Also output when conversion was successful.", |
| ) |
| |
| # Specify only one of these (defaults to --root_dir=<main source dirs>). |
| group = parser.add_mutually_exclusive_group() |
| group.add_argument( |
| "files", nargs="*", help="Converts (or generates) the given files", default=[] |
| ) |
| group.add_argument( |
| "--dir", help="Converts the BUILD file in the given directory", default=None |
| ) |
| default_root_dirs = ( |
| repo_cfg.DEFAULT_ROOT_DIRS if hasattr(repo_cfg, "DEFAULT_ROOT_DIRS") else [] |
| ) |
| group.add_argument( |
| "--root_dir", |
| nargs="+", |
| help="Converts all BUILD files under a root directory", |
| default=default_root_dirs, |
| ) |
| |
| args = parser.parse_args() |
| |
| # 'files' and '--dir' take precedence over '--root_dir'. |
| # They are mutually exclusive, but the default value is still set. |
| if args.files or args.dir: |
| args.root_dir = None |
| |
| return args |
| |
| |
| def setup_environment(): |
| """Sets up some environment globals.""" |
| global repo_root |
| global repo_cfg |
| |
| # Scan up the directory tree for a repo config file. |
| check_dir = os.getcwd() |
| while not os.path.exists(os.path.join(check_dir, REPO_CFG_FILE)): |
| new_check_dir = os.path.dirname(check_dir) |
| if not new_check_dir or new_check_dir == check_dir: |
| print( |
| f"ERROR: Could not find {REPO_CFG_FILE} in a parent directory " |
| f"of {os.getcwd()}" |
| ) |
| sys.exit(1) |
| check_dir = new_check_dir |
| repo_root = check_dir |
| log(f"Using repo root {repo_root}") |
| |
| # Dynamically load the config file as a module. |
| orig_dont_write_bytecode = sys.dont_write_bytecode |
| sys.dont_write_bytecode = True # Don't generate __pycache__ dir |
| repo_cfg_path = os.path.join(repo_root, REPO_CFG_FILE) |
| spec = importlib.util.spec_from_file_location(REPO_CFG_MODULE_NAME, repo_cfg_path) |
| if spec and spec.loader: |
| repo_cfg = importlib.util.module_from_spec(spec) |
| sys.modules[REPO_CFG_MODULE_NAME] = repo_cfg |
| spec.loader.exec_module(repo_cfg) |
| sys.dont_write_bytecode = orig_dont_write_bytecode |
| else: |
| print(f"INTERNAL ERROR: Could not evaluate {repo_cfg_path} as module") |
| sys.exit(1) |
| |
| |
| def repo_relpath(path): |
| return os.path.relpath(path, repo_root).replace("\\", "/") |
| |
| |
| def log(string, *args, indent=0, **kwargs): |
| print( |
| textwrap.indent(string, prefix=(indent * " ")), *args, **kwargs, file=sys.stderr |
| ) |
| |
| |
| def convert_directories(directories, write_files, allow_partial_conversion, verbosity): |
| failure_dirs = [] |
| skip_count = 0 |
| success_count = 0 |
| noop_count = 0 |
| for directory in directories: |
| status = convert_directory( |
| directory, |
| write_files=write_files, |
| allow_partial_conversion=allow_partial_conversion, |
| verbosity=verbosity, |
| ) |
| if status == Status.FAILED: |
| failure_dirs.append(repo_relpath(directory)) |
| elif status == Status.SKIPPED: |
| skip_count += 1 |
| elif status == Status.UPDATED: |
| success_count += 1 |
| elif status == Status.NOOP: |
| noop_count += 1 |
| |
| log( |
| f"{success_count} CMakeLists.txt files were updated, {skip_count} were" |
| f" skipped, and {noop_count} required no change." |
| ) |
| if failure_dirs: |
| log( |
| f"ERROR: Encountered unexpected errors converting {len(failure_dirs)}" |
| " directories:" |
| ) |
| log("\n".join(failure_dirs), indent=2) |
| sys.exit(1) |
| |
| |
| def convert_directory(directory_path, write_files, allow_partial_conversion, verbosity): |
| if not os.path.isdir(directory_path): |
| raise FileNotFoundError(f"Cannot find directory '{directory_path}'") |
| |
| rel_dir_path = repo_relpath(directory_path) |
| if verbosity >= 1: |
| log(f"Processing {rel_dir_path}") |
| |
| # Scan for a BUILD file. |
| build_file_found = False |
| build_file_basenames = ["BUILD", "BUILD.bazel"] |
| for build_file_basename in build_file_basenames: |
| build_file_path = os.path.join(directory_path, build_file_basename) |
| |
| rel_build_file_path = repo_relpath(build_file_path) |
| if os.path.isfile(build_file_path): |
| build_file_found = True |
| break |
| cmakelists_file_path = os.path.join(directory_path, "CMakeLists.txt") |
| rel_cmakelists_file_path = repo_relpath(cmakelists_file_path) |
| |
| if not build_file_found: |
| return Status.NO_BUILD_FILE |
| |
| autogeneration_tag = f"Autogenerated by {repo_relpath(os.path.abspath(__file__))}" |
| |
| header = "\n".join( |
| ["#" * 80] |
| + [ |
| l.ljust(79) + "#" |
| for l in [ |
| f"# {autogeneration_tag} from", |
| f"# {rel_build_file_path}", |
| "#", |
| "# Use iree_cmake_extra_content from iree/build_defs.oss.bzl to add arbitrary", |
| "# CMake-only content.", |
| "#", |
| f"# To disable autogeneration for this file entirely, delete this header.", |
| ] |
| ] |
| + ["#" * 80] |
| ) |
| |
| old_lines = [] |
| possible_preserved_header_lines = [] |
| preserved_footer_lines = ["\n" + PRESERVE_BELOW_TAG + "\n"] |
| |
| # Read CMakeLists.txt and check if it has the auto-generated header. |
| found_preserve_below_tag = False |
| found_preserve_above_tag = False |
| if os.path.isfile(cmakelists_file_path): |
| found_autogeneration_tag = False |
| with open(cmakelists_file_path) as f: |
| old_lines = f.readlines() |
| |
| for line in old_lines: |
| if not found_preserve_above_tag: |
| possible_preserved_header_lines.append(line) |
| if not found_autogeneration_tag and autogeneration_tag in line: |
| found_autogeneration_tag = True |
| if not found_preserve_below_tag and PRESERVE_BELOW_TAG in line: |
| found_preserve_below_tag = True |
| elif not found_preserve_above_tag and PRESERVE_ABOVE_TAG in line: |
| found_preserve_above_tag = True |
| elif found_preserve_below_tag: |
| preserved_footer_lines.append(line) |
| if not found_autogeneration_tag: |
| if verbosity >= 1: |
| log(f"Skipped. Did not find autogeneration line.", indent=2) |
| return Status.SKIPPED |
| preserved_header = ( |
| "".join(possible_preserved_header_lines) if found_preserve_above_tag else "" |
| ) |
| preserved_footer = "".join(preserved_footer_lines) |
| |
| # Read the Bazel BUILD file and interpret it. |
| with open(build_file_path, "rt") as build_file: |
| build_file_contents = build_file.read() |
| if "bazel-to-cmake: skip" in build_file_contents: |
| return Status.SKIPPED |
| build_file_code = compile(build_file_contents, build_file_path, "exec") |
| try: |
| converted_build_file = bazel_to_cmake_converter.convert_build_file( |
| build_file_code, |
| repo_cfg=repo_cfg, |
| build_dir=directory_path, |
| allow_partial_conversion=allow_partial_conversion, |
| ) |
| except (NameError, NotImplementedError) as e: |
| log( |
| f"ERROR generating {rel_dir_path}.\n" |
| f"Missing a rule handler in bazel_to_cmake_converter.py?\n" |
| f"Reason: `{type(e).__name__}: {e}`", |
| indent=2, |
| ) |
| return Status.FAILED |
| except KeyError as e: |
| log( |
| f"ERROR generating {rel_dir_path}.\n" |
| f"Missing a conversion in bazel_to_cmake_targets.py?\n" |
| f"Reason: `{type(e).__name__}: {e}`", |
| indent=2, |
| ) |
| return Status.FAILED |
| converted_content = ( |
| preserved_header + header + converted_build_file + preserved_footer |
| ) |
| if write_files: |
| with open(cmakelists_file_path, "wt") as cmakelists_file: |
| cmakelists_file.write(converted_content) |
| else: |
| print(converted_content, end="") |
| |
| if converted_content == "".join(old_lines): |
| if verbosity >= 2: |
| log(f"{rel_cmakelists_file_path} required no update", indent=2) |
| return Status.NOOP |
| |
| if verbosity >= 2: |
| log( |
| f"Successfly generated {rel_cmakelists_file_path}" |
| f" from {rel_build_file_path}", |
| indent=2, |
| ) |
| return Status.UPDATED |
| |
| |
| def main(args): |
| """Runs Bazel to CMake conversion.""" |
| global repo_root |
| |
| write_files = not args.preview |
| |
| if args.files: |
| convert_directories( |
| [Path(file).parent for file in args.files], |
| write_files=write_files, |
| allow_partial_conversion=args.allow_partial_conversion, |
| verbosity=args.verbosity, |
| ) |
| elif args.root_dir: |
| for root_dir in args.root_dir: |
| root_directory_path = os.path.join(repo_root, root_dir) |
| log(f"Converting directory tree rooted at: {root_directory_path}") |
| convert_directories( |
| (root for root, _, _ in os.walk(root_directory_path)), |
| write_files=write_files, |
| allow_partial_conversion=args.allow_partial_conversion, |
| verbosity=args.verbosity, |
| ) |
| elif args.dir: |
| convert_directories( |
| [os.path.join(repo_root, args.dir)], |
| write_files=write_files, |
| allow_partial_conversion=args.allow_partial_conversion, |
| verbosity=args.verbosity, |
| ) |
| else: |
| log( |
| f"ERROR: None of (positional) 'file', '--root-dir', or '--dir' " |
| f"arguments or DEFAULT_ROOT_DIRS in .bazel_to_cmake.cfg.py: No " |
| f"conversion will be done" |
| ) |
| sys.exit(1) |
| |
| |
| if __name__ == "__main__": |
| setup_environment() |
| main(parse_arguments()) |