utils: make util to print nearest symbol to address

utils/get_nearest_symbol.py

@@ -0,0 +1,38 @@
+#!/usr/bin/env python3
+import re
+import sys
+from lib.gbtool import *
+
+def get_relative_symbol(sym_table, address):
+	relative = 0
+	while not (is_symbol_defined(sym_table, address)):
+		address -= 1
+		relative += 1
+	if relative == 0:
+		return get_symbol(sym_table, address)
+	return '%s + %d' % (get_symbol(sym_table, address), relative)
+
+if __name__ == '__main__':
+	if len(sys.argv) < 2:
+		print(f'{sys.argv[0]} address')
+		print('\taddress can be in BB:AAAA form or as a hex number')
+		exit(0)
+
+	addr_str = lambda x: '%03x:%04x' % x
+
+	# extract symbols
+	with open('shi_kong_xing_shou.sym', 'r') as sym:
+		string = sym.read()
+		symbol = read_symbols(string)
+		rom_sym = symbol['rom']
+		ram_sym = symbol['ram']
+
+	# get address
+	s = sys.argv[1]
+	s_= re.match('([0-9a-fA-F]+):([0-9a-fA-F]{4})$', s)
+	if s_:
+		start = addr2offset(*str2addr(s))
+	else:
+		start = int(s, 16)
+
+	print(get_relative_symbol(rom_sym, start))

utils/lib/gbtool.py

@@ -86,6 +86,9 @@ def get_symbol(symbol_table, address):
 	else:
 		return 'unk_%03x_%04x' % offset2addr(address)
 
+def is_symbol_defined(symbol_table, address):
+	return address in symbol_table
+
 # syntactic sugar
 get_number = lambda src, bytes: int.from_bytes(src.read(bytes), byteorder='little')