123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177 |
- #!/usr/bin/env python3
- """Script to generate Chromium's Abseil .def files at roll time.
- This script generates //third_party/abseil-app/absl/symbols_*.def at Abseil
- roll time.
- Since Abseil doesn't export symbols, Chromium is forced to consider all
- Abseil's symbols as publicly visible. On POSIX it is possible to use
- -fvisibility=default but on Windows a .def file with all the symbols
- is needed.
- Unless you are on a Windows machine, you need to set up your Chromium
- checkout for cross-compilation by following the instructions at
- https://chromium.googlesource.com/chromium/src.git/+/main/docs/win_cross.md.
- If you are on Windows, you may need to tweak this script to run, e.g. by
- changing "gn" to "gn.bat", changing "llvm-nm" to the name of your copy of
- llvm-nm, etc.
- """
- import fnmatch
- import logging
- import os
- import re
- import subprocess
- import sys
- import tempfile
- import time
- # Matches a mangled symbol that has 'absl' in it, this should be a good
- # enough heuristic to select Abseil symbols to list in the .def file.
- ABSL_SYM_RE = re.compile(r'0* [BT] (?P<symbol>(\?+)[^\?].*absl.*)')
- if sys.platform == 'win32':
- # Typical dumpbin /symbol lines look like this:
- # 04B 0000000C SECT14 notype Static | ?$S1@?1??SetCurrent
- # ThreadIdentity@base_internal@absl@@YAXPAUThreadIdentity@12@P6AXPAX@Z@Z@4IA
- # (unsigned int `void __cdecl absl::base_internal::SetCurrentThreadIdentity...
- # We need to start on "| ?" and end on the first " (" (stopping on space would
- # also work).
- # This regex is identical inside the () characters except for the ? after .*,
- # which is needed to prevent greedily grabbing the undecorated version of the
- # symbols.
- ABSL_SYM_RE = '.*External \| (?P<symbol>(\?+)[^\?].*?absl.*?) \(.*'
- # Typical exported symbols in dumpbin /directives look like:
- # /EXPORT:?kHexChar@numbers_internal@absl@@3QBDB,DATA
- ABSL_EXPORTED_RE = '.*/EXPORT:(.*),.*'
- def _DebugOrRelease(is_debug):
- return 'dbg' if is_debug else 'rel'
- def _GenerateDefFile(cpu, is_debug, extra_gn_args=[], suffix=None):
- """Generates a .def file for the absl component build on the specified CPU."""
- if extra_gn_args:
- assert suffix != None, 'suffix is needed when extra_gn_args is used'
- flavor = _DebugOrRelease(is_debug)
- gn_args = [
- 'ffmpeg_branding = "Chrome"',
- 'is_component_build = true',
- 'is_debug = {}'.format(str(is_debug).lower()),
- 'proprietary_codecs = true',
- 'symbol_level = 0',
- 'target_cpu = "{}"'.format(cpu),
- 'target_os = "win"',
- ]
- gn_args.extend(extra_gn_args)
- gn = 'gn'
- autoninja = 'autoninja'
- symbol_dumper = ['third_party/llvm-build/Release+Asserts/bin/llvm-nm']
- if sys.platform == 'win32':
- gn = 'gn.bat'
- autoninja = 'autoninja.bat'
- symbol_dumper = ['dumpbin', '/symbols']
- import shutil
- if not shutil.which('dumpbin'):
- logging.error('dumpbin not found. Run tools\win\setenv.bat.')
- exit(1)
- with tempfile.TemporaryDirectory() as out_dir:
- logging.info('[%s - %s] Creating tmp out dir in %s', cpu, flavor, out_dir)
- subprocess.check_call([gn, 'gen', out_dir, '--args=' + ' '.join(gn_args)],
- cwd=os.getcwd())
- logging.info('[%s - %s] gn gen completed', cpu, flavor)
- subprocess.check_call(
- [autoninja, '-C', out_dir, 'third_party/abseil-cpp:absl_component_deps'],
- cwd=os.getcwd())
- logging.info('[%s - %s] autoninja completed', cpu, flavor)
- obj_files = []
- for root, _dirnames, filenames in os.walk(
- os.path.join(out_dir, 'obj', 'third_party', 'abseil-cpp')):
- matched_files = fnmatch.filter(filenames, '*.obj')
- obj_files.extend((os.path.join(root, f) for f in matched_files))
- logging.info('[%s - %s] Found %d object files.', cpu, flavor, len(obj_files))
- absl_symbols = set()
- dll_exports = set()
- if sys.platform == 'win32':
- for f in obj_files:
- # Track all of the functions exported with __declspec(dllexport) and
- # don't list them in the .def file - double-exports are not allowed. The
- # error is "lld-link: error: duplicate /export option".
- exports_out = subprocess.check_output(['dumpbin', '/directives', f], cwd=os.getcwd())
- for line in exports_out.splitlines():
- line = line.decode('utf-8')
- match = re.match(ABSL_EXPORTED_RE, line)
- if match:
- dll_exports.add(match.groups()[0])
- for f in obj_files:
- stdout = subprocess.check_output(symbol_dumper + [f], cwd=os.getcwd())
- for line in stdout.splitlines():
- try:
- line = line.decode('utf-8')
- except UnicodeDecodeError:
- # Due to a dumpbin bug there are sometimes invalid utf-8 characters in
- # the output. This only happens on an unimportant line so it can
- # safely and silently be skipped.
- # https://developercommunity.visualstudio.com/content/problem/1091330/dumpbin-symbols-produces-randomly-wrong-output-on.html
- continue
- match = re.match(ABSL_SYM_RE, line)
- if match:
- symbol = match.group('symbol')
- assert symbol.count(' ') == 0, ('Regex matched too much, probably got '
- 'undecorated name as well')
- # Avoid getting names exported with dllexport, to avoid
- # "lld-link: error: duplicate /export option" on symbols such as:
- # ?kHexChar@numbers_internal@absl@@3QBDB
- if symbol in dll_exports:
- continue
- # Avoid to export deleting dtors since they trigger
- # "lld-link: error: export of deleting dtor" linker errors, see
- # crbug.com/1201277.
- if symbol.startswith('??_G'):
- continue
- absl_symbols.add(symbol)
- logging.info('[%s - %s] Found %d absl symbols.', cpu, flavor, len(absl_symbols))
- if extra_gn_args:
- def_file = os.path.join('third_party', 'abseil-cpp',
- 'symbols_{}_{}_{}.def'.format(cpu, flavor, suffix))
- else:
- def_file = os.path.join('third_party', 'abseil-cpp',
- 'symbols_{}_{}.def'.format(cpu, flavor))
- with open(def_file, 'w', newline='') as f:
- f.write('EXPORTS\n')
- for s in sorted(absl_symbols):
- f.write(' {}\n'.format(s))
- # Hack, it looks like there is a race in the directory cleanup.
- time.sleep(10)
- logging.info('[%s - %s] .def file successfully generated.', cpu, flavor)
- if __name__ == '__main__':
- logging.getLogger().setLevel(logging.INFO)
- if sys.version_info.major == 2:
- logging.error('This script requires Python 3.')
- exit(1)
- if not os.getcwd().endswith('src') or not os.path.exists('chrome/browser'):
- logging.error('Run this script from a chromium/src/ directory.')
- exit(1)
- _GenerateDefFile('x86', True)
- _GenerateDefFile('x86', False)
- _GenerateDefFile('x64', True)
- _GenerateDefFile('x64', False)
- _GenerateDefFile('x64', False, ['is_asan = true'], 'asan')
- _GenerateDefFile('arm64', True)
- _GenerateDefFile('arm64', False)
|