gecko-dev/build/unix/rewrite_asan_dylib.py
2020-01-02 17:27:48 +00:00

121 lines
4.5 KiB
Python

# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at http://mozilla.org/MPL/2.0/.
from __future__ import absolute_import, print_function, unicode_literals
import re
import sys
import os
import subprocess
import shutil
from buildconfig import substs
'''
Scans the given directories for binaries referencing the AddressSanitizer
runtime library, copies it to the main directory and rewrites binaries to not
reference it with absolute paths but with @executable_path instead.
'''
# This is the dylib we're looking for
DYLIB_NAME = 'libclang_rt.asan_osx_dynamic.dylib'
def resolve_rpath(filename):
otoolOut = subprocess.check_output([substs['OTOOL'], '-l', filename],
universal_newlines=True)
currentCmd = None
# The lines we need to find look like this:
# ...
# Load command 22
# cmd LC_RPATH
# cmdsize 80
# path /home/build/src/clang/bin/../lib/clang/3.8.0/lib/darwin (offset 12)
# Load command 23
# ...
# Other load command types have a varying number of fields.
for line in otoolOut.splitlines():
cmdMatch = re.match(r'^\s+cmd ([A-Z_]+)', line)
if cmdMatch is not None:
currentCmd = cmdMatch.group(1)
continue
if currentCmd == 'LC_RPATH':
pathMatch = re.match(r'^\s+path (.*) \(offset \d+\)', line)
if pathMatch is not None:
path = pathMatch.group(1)
if os.path.isdir(path):
return path
sys.stderr.write('@rpath could not be resolved from %s\n' % filename)
sys.exit(1)
def scan_directory(path):
dylibCopied = False
for root, subdirs, files in os.walk(path):
for filename in files:
filename = os.path.join(root, filename)
# Skip all files that aren't either dylibs or executable
if not (filename.endswith('.dylib') or os.access(filename, os.X_OK)):
continue
try:
otoolOut = subprocess.check_output(
[substs['OTOOL'], '-L', filename], universal_newlines=True)
except Exception:
# Errors are expected on non-mach executables, ignore them and continue
continue
for line in otoolOut.splitlines():
if DYLIB_NAME in line:
absDylibPath = line.split()[0]
# Don't try to rewrite binaries twice
if absDylibPath.startswith('@executable_path/'):
continue
if not dylibCopied:
if absDylibPath.startswith('@rpath/'):
rpath = resolve_rpath(filename)
copyDylibPath = absDylibPath.replace(
'@rpath', rpath)
else:
copyDylibPath = absDylibPath
if os.path.isfile(copyDylibPath):
# Copy the runtime once to the main directory, which is passed
# as the argument to this function.
shutil.copy(copyDylibPath, path)
# Now rewrite the library itself
subprocess.check_call(
[substs['INSTALL_NAME_TOOL'], '-id',
'@executable_path/' + DYLIB_NAME,
os.path.join(path, DYLIB_NAME)])
dylibCopied = True
else:
sys.stderr.write('dylib path in %s was not found at: %s\n' % (
filename, copyDylibPath))
# Now use install_name_tool to rewrite the path in our binary
relpath = '' if path == root else os.path.relpath(
path, root) + '/'
subprocess.check_call([substs['INSTALL_NAME_TOOL'], '-change',
absDylibPath,
'@executable_path/' + relpath + DYLIB_NAME,
filename])
break
if not dylibCopied:
sys.stderr.write('%s could not be found\n' % DYLIB_NAME)
sys.exit(1)
if __name__ == '__main__':
for d in sys.argv[1:]:
scan_directory(d)