botw/tools/dump_function.py

63 lines
1.7 KiB
Python
Executable File

#!/usr/bin/env python3
import argparse
from elftools.elf.elffile import ELFFile
import diff_settings
from pathlib import Path
from typing import Any, Dict
import utils
config: Dict[str, Any] = {}
diff_settings.apply(config, {})
root = Path(__file__).parent.parent
my_elf = ELFFile((root / config["myimg"]).open("rb"))
my_symtab = my_elf.get_section_by_name(".symtab")
if not my_symtab:
utils.fail(f'{config["myimg"]} has no symbol table')
def get_file_offset(elf, addr: int) -> int:
for seg in elf.iter_segments():
if seg.header["p_type"] != "PT_LOAD":
continue
if seg["p_vaddr"] <= addr < seg["p_vaddr"] + seg["p_filesz"]:
return addr - seg["p_vaddr"] + seg["p_offset"]
assert False
def get_symbol_file_offset_and_size(elf, table, name: str) -> (int, int):
syms = table.get_symbol_by_name(name)
if not syms or len(syms) != 1:
raise KeyError(name)
return get_file_offset(elf, syms[0]["st_value"]), syms[0]["st_size"]
def get_fn_from_my_elf(name: str) -> bytes:
offset, size = get_symbol_file_offset_and_size(my_elf, my_symtab, name)
my_elf.stream.seek(offset)
return my_elf.stream.read(size)
def dump_fn(name: str) -> None:
expected_dir = root / "expected"
try:
fn = get_fn_from_my_elf(name)
path = expected_dir / f"{name}.bin"
path.parent.mkdir(exist_ok=True)
path.write_bytes(fn)
except KeyError:
utils.fail("could not find function")
def main() -> None:
parser = argparse.ArgumentParser()
parser.add_argument("function_name", help="Name of the function to dump")
args = parser.parse_args()
dump_fn(args.function_name)
if __name__ == "__main__":
main()