Add script to apply mapped symbol from objdiff

Author: KooShnoo

tools/apply_symbol_mappings.py

@@ -0,0 +1,56 @@
+"""
+copies mapped symbols from objdiff.json to symbols.txt
+
+objdiff allows one to map symbols from the programmer's decompiled binary to the original target binary.
+this script will find those mapped symbols, and write the programmer's updated names to `symbols.txt`.
+
+example: say you have changed the signature/name of a function from foo(short) -> bar(long).
+now, the symbol from your new object is `bar__Fl`, but symbols.txt still says `foo__Fs`.
+objdiff allows you to map `bar__Fl` in your new object to `foo__Fs` in the target object.
+this script will automatically replace `foo__Fs` with `bar__Fl` in `symbols.txt`.
+"""
+
+import json
+
+with open("./objdiff.json") as f:
+    objdiff_config = json.load(f)
+
+units = objdiff_config["units"]
+
+symbol_mappings = {}
+for unit in units:
+    symbol_mapping = unit.get("symbol_mappings")
+    if symbol_mapping is None:
+        continue
+    symbol_mappings.update(symbol_mapping)
+    del unit['symbol_mappings']
+
+
+def process_symbols_txt(symbols_txt_path):
+    with open(symbols_txt_path) as f:
+        symbols = f.readlines()
+
+
+
+    for i, line in enumerate(symbols):
+        tokens = line.split()
+        old_symbol = tokens[0]
+
+        new_symbol = symbol_mappings.get(old_symbol)
+
+        if new_symbol is None:
+            continue
+
+        tokens[0] = new_symbol
+        symbols[i] = " ".join(tokens) + "\n"
+    
+    with open(symbols_txt_path, "w") as f:
+        f.writelines(symbols)
+        
+process_symbols_txt("./config/RMCP01/module/symbols.txt")
+process_symbols_txt("./config/RMCP01/symbols.txt")
+
+
+
+with open("./objdiff.json", "w") as f:
+    json.dump(objdiff_config, f)