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()
101