xref: /llvm-project/compiler-rt/lib/dfsan/scripts/build-libc-list.py (revision f98ee40f4b5d7474fc67e82824bf6abbaedb7b1c) 
1#!/usr/bin/env python3
2# ===- lib/dfsan/scripts/build-libc-list.py ---------------------------------===#
3#
4# Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5# See https://llvm.org/LICENSE.txt for license information.
6# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7#
8# ===------------------------------------------------------------------------===#
9# The purpose of this script is to identify every function symbol in a set of
10# libraries (in this case, libc and libgcc) so that they can be marked as
11# uninstrumented, thus allowing the instrumentation pass to treat calls to those
12# functions correctly.
13
14# Typical usage will list runtime libraries which are not instrumented by dfsan.
15# This would include libc, and compiler builtins.
16#
17# ./build-libc-list.py \
18#    --lib-file=/lib/x86_64-linux-gnu/ld-linux-x86-64.so.2 \
19#    --lib-file=/lib/x86_64-linux-gnu/libanl.so.1 \
20#    --lib-file=/lib/x86_64-linux-gnu/libBrokenLocale.so.1 \
21#    --lib-file=/lib/x86_64-linux-gnu/libcidn.so.1 \
22#    --lib-file=/lib/x86_64-linux-gnu/libcrypt.so.1 \
23#    --lib-file=/lib/x86_64-linux-gnu/libc.so.6 \
24#    --lib-file=/lib/x86_64-linux-gnu/libdl.so.2 \
25#    --lib-file=/lib/x86_64-linux-gnu/libm.so.6 \
26#    --lib-file=/lib/x86_64-linux-gnu/libnsl.so.1 \
27#    --lib-file=/lib/x86_64-linux-gnu/libpthread.so.0 \
28#    --lib-file=/lib/x86_64-linux-gnu/libresolv.so.2 \
29#    --lib-file=/lib/x86_64-linux-gnu/librt.so.1 \
30#    --lib-file=/lib/x86_64-linux-gnu/libthread_db.so.1 \
31#    --lib-file=/lib/x86_64-linux-gnu/libutil.so.1 \
32#    --lib-file=/usr/lib/x86_64-linux-gnu/libc_nonshared.a \
33#    --lib-file=/usr/lib/x86_64-linux-gnu/libpthread_nonshared.a \
34#    --lib-file=/lib/x86_64-linux-gnu/libgcc_s.so.1 \
35#    --lib-file=/usr/lib/gcc/x86_64-linux-gnu/4.6/libgcc.a \
36#    --error-missing-lib
37
38import os
39import subprocess
40import sys
41from optparse import OptionParser
42
43
44def defined_function_list(lib):
45    """Get non-local function symbols from lib."""
46    functions = []
47    readelf_proc = subprocess.Popen(
48        ["readelf", "-s", "-W", lib], stdout=subprocess.PIPE
49    )
50    readelf = readelf_proc.communicate()[0].decode().split("\n")
51    if readelf_proc.returncode != 0:
52        raise subprocess.CalledProcessError(readelf_proc.returncode, "readelf")
53    for line in readelf:
54        if (
55            (line[31:35] == "FUNC" or line[31:36] == "IFUNC")
56            and line[39:44] != "LOCAL"
57            and line[55:58] != "UND"
58        ):
59            function_name = line[59:].split("@")[0]
60            functions.append(function_name)
61    return functions
62
63
64p = OptionParser()
65
66p.add_option(
67    "--lib-file",
68    action="append",
69    metavar="PATH",
70    help="Specific library files to add.",
71    default=[],
72)
73
74p.add_option(
75    "--error-missing-lib",
76    action="store_true",
77    help="Make this script exit with an error code if any library is missing.",
78    dest="error_missing_lib",
79    default=False,
80)
81
82(options, args) = p.parse_args()
83
84libs = options.lib_file
85if not libs:
86    print("No libraries provided.", file=sys.stderr)
87    exit(1)
88
89missing_lib = False
90functions = []
91for l in libs:
92    if os.path.exists(l):
93        functions += defined_function_list(l)
94    else:
95        missing_lib = True
96        print("warning: library %s not found" % l, file=sys.stderr)
97
98if options.error_missing_lib and missing_lib:
99    print("Exiting with failure code due to missing library.", file=sys.stderr)
100    exit(1)
101
102for f in sorted(set(functions)):
103    print("fun:%s=uninstrumented" % f)
104