clangd/.github/workflows/lib_compat_test.py
2020-05-08 00:01:38 +02:00

90 lines
2.8 KiB
Python
Executable File

#!/usr/bin/env python3
# Verifies a binary uses only dynamic symbols from whitelisted library versions.
# Prints the disallowed symbols and their versions on failure.
# Usage: lib_compat_test.py bin/clangd --lib=GLIBC_2.18
import argparse
import subprocess
import sys
parser = argparse.ArgumentParser()
parser.add_argument("binary")
parser.add_argument(
"--lib",
action="append",
default=[],
help="Whitelist a library, e.g. GLIBC_2.18 or GLIBC",
)
parser.add_argument(
"--sym", action="append", default=[], help="Whitelist a symbol, e.g. crc32"
)
args = parser.parse_args()
# Parses GLIBC_2.3 into ("GLIBC", [2,3])
# Parses GLIBC into ("GLIBC", None)
def parse_version(version):
parts = version.rsplit("_", 1)
if len(parts) == 1:
return (version, None)
try:
return (parts[0], [int(p) for p in parts[1].split(".")])
except ValueError:
return (version, None)
lib_versions = dict([parse_version(v) for v in args.lib])
# Determines whether all symbols with version 'lib' are acceptable.
# A versioned library is name_x.y.z by convention.
def accept_lib(lib):
(lib, ver) = parse_version(lib)
if not lib in lib_versions: # Non-whitelisted library.
return False
if lib_versions[lib] is None: # Unrestricted version
return True
if ver is None: # Lib has non-numeric version, library restricts version.
return False
return ver <= lib_versions[lib]
# Determines whether an optionally-versioned symbol is acceptable.
# A versioned symbol is symbol@version as output by nm.
def accept_symbol(sym):
if sym in args.sym:
return True
split = sym.split("@", 1)
return (split[0] in args.sym) or (len(split) == 2 and accept_lib(split[1]))
# Run nm to find the undefined symbols, and check whether each is acceptable.
nm = subprocess.run(
["nm", "-uD", "--with-symbol-version", args.binary],
stdout=subprocess.PIPE,
universal_newlines=True,
)
nm.check_returncode()
status = 0
for line in nm.stdout.splitlines():
# line = " U foo@GLIBC_2.3"
parts = line.split()
if len(parts) != 2:
print("Unparseable nm output: ", line, file=sys.stderr)
status = 2
continue
if parts[0] == "w": # Weak-undefined symbol, not actually required.
continue
if not accept_symbol(parts[1]):
print(parts[1])
status = 1
if status == 1:
print(
"Binary depends on disallowed symbols above. Use some combination of:\n"
" - relax the whitelist by adding --lib and --sym flags to this test\n"
" - force older symbol versions by updating lib_compat.h\n"
" - avoid dynamic dependencies by changing CMake configuration\n"
" - remove bad dependencies from the code",
file=sys.stderr,
)
sys.exit(status)