1#!/usr/bin/env python3
  2# SPDX-License-Identifier: GPL-2.0
  3#
  4# Copyright (C) Google LLC, 2020
  5#
  6# Author: Nathan Huckleberry <nhuck@google.com>
  7#
  8"""A helper routine run clang-tidy and the clang static-analyzer on
  9compile_commands.json.
 10"""
 11
 12import argparse
 13import json
 14import multiprocessing
 15import subprocess
 16import sys
 17
 18
 19def parse_arguments():
 20    """Set up and parses command-line arguments.
 21    Returns:
 22        args: Dict of parsed args
 23        Has keys: [path, type]
 24    """
 25    usage = """Run clang-tidy or the clang static-analyzer on a
 26        compilation database."""
 27    parser = argparse.ArgumentParser(description=usage)
 28
 29    type_help = "Type of analysis to be performed"
 30    parser.add_argument("type",
 31                        choices=["clang-tidy", "clang-analyzer"],
 32                        help=type_help)
 33    path_help = "Path to the compilation database to parse"
 34    parser.add_argument("path", type=str, help=path_help)
 35
 36    checks_help = "Checks to pass to the analysis"
 37    parser.add_argument("-checks", type=str, default=None, help=checks_help)
 38    header_filter_help = "Pass the -header-filter value to the tool"
 39    parser.add_argument("-header-filter", type=str, default=None, help=header_filter_help)
 40
 41    return parser.parse_args()
 42
 43
 44def init(l, a):
 45    global lock
 46    global args
 47    lock = l
 48    args = a
 49
 50
 51def run_analysis(entry):
 52    # Disable all checks, then re-enable the ones we want
 53    global args
 54    checks = None
 55    if args.checks:
 56        checks = args.checks.split(',')
 57    else:
 58        checks = ["-*"]
 59        if args.type == "clang-tidy":
 60            checks.append("linuxkernel-*")
 61        else:
 62            checks.append("clang-analyzer-*")
 63            checks.append("-clang-analyzer-security.insecureAPI.DeprecatedOrUnsafeBufferHandling")
 64    file = entry["file"]
 65    if not file.endswith(".c") and not file.endswith(".cpp"):
 66        with lock:
 67            print(f"Skipping non-C file: '{file}'", file=sys.stderr)
 68        return
 69    pargs = ["clang-tidy", "-p", args.path, "-checks=" + ",".join(checks)]
 70    if args.header_filter:
 71        pargs.append("-header-filter=" + args.header_filter)
 72    pargs.append(file)
 73    p = subprocess.run(pargs,
 74                       stdout=subprocess.PIPE,
 75                       stderr=subprocess.STDOUT,
 76                       cwd=entry["directory"])
 77    with lock:
 78        sys.stderr.buffer.write(p.stdout)
 79
 80
 81def main():
 82    try:
 83        args = parse_arguments()
 84
 85        lock = multiprocessing.Lock()
 86        pool = multiprocessing.Pool(initializer=init, initargs=(lock, args))
 87        # Read JSON data into the datastore variable
 88        with open(args.path, "r") as f:
 89            datastore = json.load(f)
 90            pool.map(run_analysis, datastore)
 91    except BrokenPipeError:
 92        # Python flushes standard streams on exit; redirect remaining output
 93        # to devnull to avoid another BrokenPipeError at shutdown
 94        devnull = os.open(os.devnull, os.O_WRONLY)
 95        os.dup2(devnull, sys.stdout.fileno())
 96        sys.exit(1)  # Python exits with error code 1 on EPIPE
 97
 98
 99if __name__ == "__main__":
100    main()