qemu/scripts/undefsym.py

49 lines
1.6 KiB
Python

#!/usr/bin/env python3
# Before a shared module's DSO is produced, a static library is built for it
# and passed to this script. The script generates -Wl,-u options to force
# the inclusion of symbol from libqemuutil.a if the shared modules need them,
# This is necessary because the modules may use functions not needed by the
# executable itself, which would cause the function to not be linked in.
# Then the DSO loading would fail because of the missing symbol.
import sys
import subprocess
def filter_lines_set(stdout, from_staticlib):
linesSet = set()
for line in stdout.splitlines():
tokens = line.split(b' ')
if len(tokens) >= 2:
if from_staticlib and tokens[1] == b'U':
continue
if not from_staticlib and tokens[1] != b'U':
continue
new_line = b'-Wl,-u,' + tokens[0]
if not new_line in linesSet:
linesSet.add(new_line)
return linesSet
def main(args):
if len(args) <= 3:
sys.exit(0)
nm = args[1]
staticlib = args[2]
pc = subprocess.run([nm, "-P", "-g", staticlib], stdout=subprocess.PIPE)
if pc.returncode != 0:
sys.exit(1)
staticlib_syms = filter_lines_set(pc.stdout, True)
shared_modules = args[3:]
pc = subprocess.run([nm, "-P", "-g"] + shared_modules, stdout=subprocess.PIPE)
if pc.returncode != 0:
sys.exit(1)
modules_undef_syms = filter_lines_set(pc.stdout, False)
lines = sorted(staticlib_syms.intersection(modules_undef_syms))
sys.stdout.buffer.write(b'\n'.join(lines))
if __name__ == "__main__":
main(sys.argv)