botw/tools/show_vtable.py

116 lines
3.7 KiB
Python
Executable File

#!/usr/bin/env python3
import argparse
from colorama import Fore, Style
import cxxfilt
from elftools.elf.elffile import ELFFile
import diff_settings
from pathlib import Path
import struct
from typing import Any, Dict, Optional
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 build_symbol_table(symtab) -> Dict[int, str]:
table = dict()
for sym in symtab.iter_symbols():
addr = sym["st_value"]
existing_value = table.get(addr, None)
if existing_value is None or not existing_value.startswith("_Z"):
table[addr] = sym.name
return table
def find_vtable(symtab, class_name: str) -> Optional[str]:
OFFSET = len("vtable for ")
for sym in symtab.iter_symbols():
if not sym.name.startswith("_ZTV"):
continue
if cxxfilt.demangle(sym.name)[OFFSET:] == class_name:
return sym.name
return None
def bold(s) -> str:
return Style.BRIGHT + str(s) + Style.NORMAL
def dump_table(name: str) -> None:
try:
symbols = build_symbol_table(my_symtab)
decomp_symbols = {fn.decomp_name for fn in utils.get_functions() if fn.decomp_name}
offset, size = get_symbol_file_offset_and_size(my_elf, my_symtab, name)
my_elf.stream.seek(offset)
vtable_bytes = my_elf.stream.read(size)
if not vtable_bytes:
utils.fail(
"empty vtable; has the key function been implemented? (https://lld.llvm.org/missingkeyfunction.html)")
print(f"{Fore.WHITE}{Style.BRIGHT}{cxxfilt.demangle(name)}{Style.RESET_ALL}")
print(f"{Fore.YELLOW}{Style.BRIGHT}vtable @ 0x0{Style.RESET_ALL}")
assert size % 8 == 0
for i in range(size // 8):
word: int = struct.unpack_from("<Q", vtable_bytes, 8 * i)[0]
name = symbols.get(word, None)
if word == 0:
pass
elif name is not None:
demangled_name: str = cxxfilt.demangle(name)
color = Fore.GREEN if name in decomp_symbols else Fore.BLUE
print(f"{color}{bold(demangled_name)}{Style.RESET_ALL}")
print(f" {name}")
elif word & (1 << 63):
offset = -struct.unpack_from("<q", vtable_bytes, 8 * i)[0]
print()
print(f"{Fore.YELLOW}{Style.BRIGHT}vtable @ {offset:#x}{Style.RESET_ALL}")
else:
print(f"{Fore.RED}unknown data: {word:016x}{Style.RESET_ALL}")
except KeyError:
utils.fail("could not find symbol")
def main() -> None:
parser = argparse.ArgumentParser()
parser.add_argument("symbol_name", help="Name of the vtable symbol (_ZTV...) or class name")
args = parser.parse_args()
symbol_name: str = args.symbol_name
if not symbol_name.startswith("_ZTV"):
symbol_name = find_vtable(my_symtab, args.symbol_name)
dump_table(symbol_name)
if __name__ == "__main__":
main()