tools: Deduplicate code

tools/show_vtable.py

@@ -1,57 +1,22 @@
 #!/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
+from typing import Optional
 
-config: Dict[str, Any] = {}
-diff_settings.apply(config, {})
+import cxxfilt
+from colorama import Fore, Style
 
-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
+import util.elf
+from util import utils
 
 
 def find_vtable(symtab, class_name: str) -> Optional[str]:
-    OFFSET = len("vtable for ")
+    name_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:
+        if cxxfilt.demangle(sym.name)[name_offset:] == class_name:
             return sym.name
     return None
 
@@ -62,12 +27,12 @@ def bold(s) -> str:
 
 def dump_table(name: str) -> None:
     try:
-        symbols = build_symbol_table(my_symtab)
+        symbols = util.elf.build_symbol_table(util.elf.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)
+        offset, size = util.elf.get_symbol_file_offset_and_size(util.elf.my_elf, util.elf.my_symtab, name)
+        util.elf.my_elf.stream.seek(offset)
+        vtable_bytes = util.elf.my_elf.stream.read(size)
 
         if not vtable_bytes:
             utils.fail(
@@ -106,7 +71,7 @@ def main() -> None:
     symbol_name: str = args.symbol_name
 
     if not symbol_name.startswith("_ZTV"):
-        symbol_name = find_vtable(my_symtab, args.symbol_name)
+        symbol_name = find_vtable(util.elf.my_symtab, args.symbol_name)
 
     dump_table(symbol_name)