llvm-project/libcxx/utils/gen_link_script/gen_link_script.py

89 lines
2.8 KiB
Python
Executable File

#!/usr/bin/env python
#===----------------------------------------------------------------------===##
#
# The LLVM Compiler Infrastructure
#
# This file is dual licensed under the MIT and the University of Illinois Open
# Source Licenses. See LICENSE.TXT for details.
#
#===----------------------------------------------------------------------===##
import os
import sys
def print_and_exit(msg):
sys.stderr.write(msg + '\n')
sys.exit(1)
def usage_and_exit():
print_and_exit("Usage: ./gen_link_script.py [--help] [--dryrun] <path/to/libcxx.so> <abi_libname>")
def help_and_exit():
help_msg = \
"""Usage
gen_link_script.py [--help] [--dryrun] <path/to/libcxx.so> <abi_libname>
Generate a linker script that links libc++ to the proper ABI library.
The script replaces the specified libc++ symlink.
An example script for c++abi would look like "INPUT(libc++.so.1 -lc++abi)".
Arguments
<path/to/libcxx.so> - The top level symlink to the versioned libc++ shared
library. This file is replaced with a linker script.
<abi_libname> - The name of the ABI library to use in the linker script.
The name must be one of [c++abi, stdc++, supc++, cxxrt].
Exit Status:
0 if OK,
1 if the action failed.
"""
print_and_exit(help_msg)
def parse_args():
args = list(sys.argv)
del args[0]
if len(args) == 0:
usage_and_exit()
if args[0] == '--help':
help_and_exit()
dryrun = '--dryrun' == args[0]
if dryrun:
del args[0]
if len(args) != 2:
usage_and_exit()
symlink_file = args[0]
abi_libname = args[1]
return dryrun, symlink_file, abi_libname
def main():
dryrun, symlink_file, abi_libname = parse_args()
# Check that the given libc++.so file is a valid symlink.
if not os.path.islink(symlink_file):
print_and_exit("symlink file %s is not a symlink" % symlink_file)
# Read the symlink so we know what libc++ to link to in the linker script.
linked_libcxx = os.readlink(symlink_file)
# Check that the abi_libname is one of the supported values.
supported_abi_list = ['c++abi', 'stdc++', 'supc++', 'cxxrt']
if abi_libname not in supported_abi_list:
print_and_exit("abi name '%s' is not supported: Use one of %r" %
(abi_libname, supported_abi_list))
# Generate the linker script contents and print the script and destination
# information.
contents = "INPUT(%s -l%s)" % (linked_libcxx, abi_libname)
print("GENERATING SCRIPT: '%s' as file %s" % (contents, symlink_file))
# Remove the existing libc++ symlink and replace it with the script.
if not dryrun:
os.unlink(symlink_file)
with open(symlink_file, 'w') as f:
f.write(contents + "\n")
if __name__ == '__main__':
main()