From 4829226ac3d52e62a3ca3e28b92a79457c7b32f2 Mon Sep 17 00:00:00 2001 From: Ahmad Fatoum Date: Sun, 31 Jan 2021 20:40:04 +0100 Subject: Kbuild: add compile_commands.json target The JSON compilation database format specification describes a compile_commands.json file that lists how translation units are compiled by a build system. This makes integration of external tools, like IDEs, LSP servers and static analyzers easier. Import the Linux bits. The database can now be manually generated with make compile_commands.json. Signed-off-by: Ahmad Fatoum Signed-off-by: Sascha Hauer --- .gitignore | 1 + Makefile | 16 +- scripts/clang-tools/gen_compile_commands.py | 237 ++++++++++++++++++++++++++++ 3 files changed, 252 insertions(+), 2 deletions(-) create mode 100755 scripts/clang-tools/gen_compile_commands.py diff --git a/.gitignore b/.gitignore index 7fa2948bf4..d7a37b3c9b 100644 --- a/.gitignore +++ b/.gitignore @@ -87,3 +87,4 @@ GTAGS /allno.config /allrandom.config /allyes.config +/compile_commands.json diff --git a/Makefile b/Makefile index ea1d5dae1c..f3c85cff94 100644 --- a/Makefile +++ b/Makefile @@ -541,7 +541,7 @@ endif # in addition to whatever we do anyway. # Just "make" or "make all" shall build modules as well -ifneq ($(filter all _all modules,$(MAKECMDGOALS)),) +ifneq ($(filter all _all modules %compile_commands.json,$(MAKECMDGOALS)),) KBUILD_MODULES := 1 endif @@ -1104,7 +1104,7 @@ endif # CONFIG_MODULES CLEAN_DIRS += $(MODVERDIR) CLEAN_FILES += barebox System.map include/generated/barebox_default_env.h \ .tmp_version .tmp_barebox* barebox.bin barebox.map barebox.S \ - .tmp_kallsyms* barebox.ldr \ + .tmp_kallsyms* barebox.ldr compile_commands.json \ scripts/bareboxenv-target barebox-flash-image \ barebox.srec barebox.s5p barebox.ubl barebox.zynq \ barebox.uimage barebox.spi barebox.kwb barebox.kwbuart \ @@ -1162,6 +1162,18 @@ distclean: mrproper -o -name 'core' \) \ -type f -print | xargs rm -f +# Clang Tooling +# --------------------------------------------------------------------------- + +quiet_cmd_gen_compile_commands = GEN $@ + cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs)) + +compile_commands.json: scripts/clang-tools/gen_compile_commands.py \ + $(BAREBOX_OBJS) $(if $(CONFIG_PBL_IMAGE),$(BAREBOX_PBL_OBJS),) FORCE + $(call if_changed,gen_compile_commands) + +PHONY += compile_commands.json + # Brief documentation of the typical targets used # --------------------------------------------------------------------------- diff --git a/scripts/clang-tools/gen_compile_commands.py b/scripts/clang-tools/gen_compile_commands.py new file mode 100755 index 0000000000..7ed3919f45 --- /dev/null +++ b/scripts/clang-tools/gen_compile_commands.py @@ -0,0 +1,237 @@ +#!/usr/bin/env python +# SPDX-License-Identifier: GPL-2.0 +# +# Copyright (C) Google LLC, 2018 +# +# Author: Tom Roeder +# +"""A tool for generating compile_commands.json in the Linux kernel.""" + +import argparse +import json +import logging +import os +import sys +import re +import subprocess + +_DEFAULT_OUTPUT = 'compile_commands.json' +_DEFAULT_LOG_LEVEL = 'WARNING' + +_FILENAME_PATTERN = r'^\..*\.cmd$' +_LINE_PATTERN = r'^cmd_[^ ]*\.o := (.* )([^ ]*\.c)$' +_VALID_LOG_LEVELS = ['DEBUG', 'INFO', 'WARNING', 'ERROR', 'CRITICAL'] + + +def parse_arguments(): + """Sets up and parses command-line arguments. + + Returns: + log_level: A logging level to filter log output. + directory: The work directory where the objects were built. + ar: Command used for parsing .a archives. + output: Where to write the compile-commands JSON file. + paths: The list of files/directories to handle to find .cmd files. + """ + usage = 'Creates a compile_commands.json database from kernel .cmd files' + parser = argparse.ArgumentParser(description=usage) + + directory_help = ('specify the output directory used for the kernel build ' + '(defaults to the working directory)') + parser.add_argument('-d', '--directory', type=str, default='.', + help=directory_help) + + output_help = ('path to the output command database (defaults to ' + + _DEFAULT_OUTPUT + ')') + parser.add_argument('-o', '--output', type=str, default=_DEFAULT_OUTPUT, + help=output_help) + + log_level_help = ('the level of log messages to produce (defaults to ' + + _DEFAULT_LOG_LEVEL + ')') + parser.add_argument('--log_level', choices=_VALID_LOG_LEVELS, + default=_DEFAULT_LOG_LEVEL, help=log_level_help) + + ar_help = 'command used for parsing .a archives' + parser.add_argument('-a', '--ar', type=str, default='llvm-ar', help=ar_help) + + paths_help = ('directories to search or files to parse ' + '(files should be *.o, *.a, or modules.order). ' + 'If nothing is specified, the current directory is searched') + parser.add_argument('paths', type=str, nargs='*', help=paths_help) + + args = parser.parse_args() + + return (args.log_level, + os.path.abspath(args.directory), + args.output, + args.ar, + args.paths if len(args.paths) > 0 else [args.directory]) + + +def cmdfiles_in_dir(directory): + """Generate the iterator of .cmd files found under the directory. + + Walk under the given directory, and yield every .cmd file found. + + Args: + directory: The directory to search for .cmd files. + + Yields: + The path to a .cmd file. + """ + + filename_matcher = re.compile(_FILENAME_PATTERN) + + for dirpath, _, filenames in os.walk(directory): + for filename in filenames: + if filename_matcher.match(filename): + yield os.path.join(dirpath, filename) + + +def to_cmdfile(path): + """Return the path of .cmd file used for the given build artifact + + Args: + Path: file path + + Returns: + The path to .cmd file + """ + dir, base = os.path.split(path) + return os.path.join(dir, '.' + base + '.cmd') + + +def cmdfiles_for_o(obj): + """Generate the iterator of .cmd files associated with the object + + Yield the .cmd file used to build the given object + + Args: + obj: The object path + + Yields: + The path to .cmd file + """ + yield to_cmdfile(obj) + + +def cmdfiles_for_a(archive, ar): + """Generate the iterator of .cmd files associated with the archive. + + Parse the given archive, and yield every .cmd file used to build it. + + Args: + archive: The archive to parse + + Yields: + The path to every .cmd file found + """ + for obj in subprocess.check_output([ar, '-t', archive]).decode().split(): + yield to_cmdfile(obj) + + +def cmdfiles_for_modorder(modorder): + """Generate the iterator of .cmd files associated with the modules.order. + + Parse the given modules.order, and yield every .cmd file used to build the + contained modules. + + Args: + modorder: The modules.order file to parse + + Yields: + The path to every .cmd file found + """ + with open(modorder) as f: + for line in f: + ko = line.rstrip() + base, ext = os.path.splitext(ko) + if ext != '.ko': + sys.exit('{}: module path must end with .ko'.format(ko)) + mod = base + '.mod' + # The first line of *.mod lists the objects that compose the module. + with open(mod) as m: + for obj in m.readline().split(): + yield to_cmdfile(obj) + + +def process_line(root_directory, command_prefix, file_path): + """Extracts information from a .cmd line and creates an entry from it. + + Args: + root_directory: The directory that was searched for .cmd files. Usually + used directly in the "directory" entry in compile_commands.json. + command_prefix: The extracted command line, up to the last element. + file_path: The .c file from the end of the extracted command. + Usually relative to root_directory, but sometimes absolute. + + Returns: + An entry to append to compile_commands. + + Raises: + ValueError: Could not find the extracted file based on file_path and + root_directory or file_directory. + """ + # The .cmd files are intended to be included directly by Make, so they + # escape the pound sign '#', either as '\#' or '$(pound)' (depending on the + # kernel version). The compile_commands.json file is not interepreted + # by Make, so this code replaces the escaped version with '#'. + prefix = command_prefix.replace('\#', '#').replace('$(pound)', '#') + + # Use os.path.abspath() to normalize the path resolving '.' and '..' . + abs_path = os.path.abspath(os.path.join(root_directory, file_path)) + if not os.path.exists(abs_path): + raise ValueError('File %s not found' % abs_path) + return { + 'directory': root_directory, + 'file': abs_path, + 'command': prefix + file_path, + } + + +def main(): + """Walks through the directory and finds and parses .cmd files.""" + log_level, directory, output, ar, paths = parse_arguments() + + level = getattr(logging, log_level) + logging.basicConfig(format='%(levelname)s: %(message)s', level=level) + + line_matcher = re.compile(_LINE_PATTERN) + + compile_commands = [] + + for path in paths: + # If 'path' is a directory, handle all .cmd files under it. + # Otherwise, handle .cmd files associated with the file. + # Most of built-in objects are linked via archives (built-in.a or lib.a) + # but some objects are linked to vmlinux directly. + # Modules are listed in modules.order. + if os.path.isdir(path): + cmdfiles = cmdfiles_in_dir(path) + elif path.endswith('.o'): + cmdfiles = cmdfiles_for_o(path) + elif path.endswith('.a'): + cmdfiles = cmdfiles_for_a(path, ar) + elif path.endswith('modules.order'): + cmdfiles = cmdfiles_for_modorder(path) + else: + sys.exit('{}: unknown file type'.format(path)) + + for cmdfile in cmdfiles: + with open(cmdfile, 'rt') as f: + result = line_matcher.match(f.readline()) + if result: + try: + entry = process_line(directory, result.group(1), + result.group(2)) + compile_commands.append(entry) + except ValueError as err: + logging.info('Could not add line from %s: %s', + cmdfile, err) + + with open(output, 'wt') as f: + json.dump(compile_commands, f, indent=2, sort_keys=True) + + +if __name__ == '__main__': + main() -- cgit v1.2.3