1 # Copyright 2014 The Chromium Authors. All rights reserved. 2 # Use of this source code is governed by a BSD-style license that can be 3 # found in the LICENSE file. 4 5 """Common utilities for tools that deal with binary size information. 6 """ 7 8 import logging 9 import re 10 11 12 def ParseNm(nm_lines): 13 """Parse nm output, returning data for all relevant (to binary size) 14 symbols and ignoring the rest. 15 16 Args: 17 nm_lines: an iterable over lines of nm output. 18 19 Yields: 20 (symbol name, symbol type, symbol size, source file path). 21 22 Path may be None if nm couldn't figure out the source file. 23 """ 24 25 # Match lines with size, symbol, optional location, optional discriminator 26 sym_re = re.compile(r'^[0-9a-f]{8,} ' # address (8+ hex digits) 27 '([0-9a-f]{8,}) ' # size (8+ hex digits) 28 '(.) ' # symbol type, one character 29 '([^\t]+)' # symbol name, separated from next by tab 30 '(?:\t(.*):[\d\?]+)?.*$') # location 31 # Match lines with addr but no size. 32 addr_re = re.compile(r'^[0-9a-f]{8,} (.) ([^\t]+)(?:\t.*)?$') 33 # Match lines that don't have an address at all -- typically external symbols. 34 noaddr_re = re.compile(r'^ {8,} (.) (.*)$') 35 # Match lines with no symbol name, only addr and type 36 addr_only_re = re.compile(r'^[0-9a-f]{8,} (.)$') 37 38 for line in nm_lines: 39 line = line.rstrip() 40 match = sym_re.match(line) 41 if match: 42 size, sym_type, sym = match.groups()[0:3] 43 size = int(size, 16) 44 if sym_type in ('B', 'b'): 45 continue # skip all BSS for now. 46 path = match.group(4) 47 yield sym, sym_type, size, path 48 continue 49 match = addr_re.match(line) 50 if match: 51 # sym_type, sym = match.groups()[0:2] 52 continue # No size == we don't care. 53 match = noaddr_re.match(line) 54 if match: 55 sym_type, sym = match.groups() 56 if sym_type in ('U', 'w'): 57 continue # external or weak symbol 58 match = addr_only_re.match(line) 59 if match: 60 continue # Nothing to do. 61 62 63 # If we reach this part of the loop, there was something in the 64 # line that we didn't expect or recognize. 65 logging.warning('nm output parser failed to parse: %s', repr(line)) 66