1#!/usr/bin/python 2# 3# diffconfig - a tool to compare .config files. 4# 5# originally written in 2006 by Matt Mackall 6# (at least, this was in his bloatwatch source code) 7# last worked on 2008 by Tim Bird 8# 9 10import sys, os 11 12def usage(): 13 print("""Usage: diffconfig [-h] [-m] [<config1> <config2>] 14 15Diffconfig is a simple utility for comparing two .config files. 16Using standard diff to compare .config files often includes extraneous and 17distracting information. This utility produces sorted output with only the 18changes in configuration values between the two files. 19 20Added and removed items are shown with a leading plus or minus, respectively. 21Changed items show the old and new values on a single line. 22 23If -m is specified, then output will be in "merge" style, which has the 24changed and new values in kernel config option format. 25 26If no config files are specified, .config and .config.old are used. 27 28Example usage: 29 $ diffconfig .config config-with-some-changes 30-EXT2_FS_XATTR n 31 CRAMFS n -> y 32 EXT2_FS y -> n 33 LOG_BUF_SHIFT 14 -> 16 34 PRINTK_TIME n -> y 35""") 36 sys.exit(0) 37 38# returns a dictionary of name/value pairs for config items in the file 39def readconfig(config_file): 40 d = {} 41 for line in config_file: 42 line = line[:-1] 43 if line[:7] == "CONFIG_": 44 name, val = line[7:].split("=", 1) 45 d[name] = val 46 if line[-11:] == " is not set": 47 d[line[9:-11]] = "n" 48 return d 49 50def print_config(op, config, value, new_value): 51 global merge_style 52 53 if merge_style: 54 if new_value: 55 if new_value=="n": 56 print("# CONFIG_%s is not set" % config) 57 else: 58 print("CONFIG_%s=%s" % (config, new_value)) 59 else: 60 if op=="-": 61 print("-%s %s" % (config, value)) 62 elif op=="+": 63 print("+%s %s" % (config, new_value)) 64 else: 65 print(" %s %s -> %s" % (config, value, new_value)) 66 67def main(): 68 global merge_style 69 70 # parse command line args 71 if ("-h" in sys.argv or "--help" in sys.argv): 72 usage() 73 74 merge_style = 0 75 if "-m" in sys.argv: 76 merge_style = 1 77 sys.argv.remove("-m") 78 79 argc = len(sys.argv) 80 if not (argc==1 or argc == 3): 81 print("Error: incorrect number of arguments or unrecognized option") 82 usage() 83 84 if argc == 1: 85 # if no filenames given, assume .config and .config.old 86 build_dir="" 87 if "KBUILD_OUTPUT" in os.environ: 88 build_dir = os.environ["KBUILD_OUTPUT"]+"/" 89 configa_filename = build_dir + ".config.old" 90 configb_filename = build_dir + ".config" 91 else: 92 configa_filename = sys.argv[1] 93 configb_filename = sys.argv[2] 94 95 try: 96 a = readconfig(open(configa_filename)) 97 b = readconfig(open(configb_filename)) 98 except (IOError): 99 e = sys.exc_info()[1] 100 print("I/O error[%s]: %s\n" % (e.args[0],e.args[1])) 101 usage() 102 103 # print items in a but not b (accumulate, sort and print) 104 old = [] 105 for config in a: 106 if config not in b: 107 old.append(config) 108 old.sort() 109 for config in old: 110 print_config("-", config, a[config], None) 111 del a[config] 112 113 # print items that changed (accumulate, sort, and print) 114 changed = [] 115 for config in a: 116 if a[config] != b[config]: 117 changed.append(config) 118 else: 119 del b[config] 120 changed.sort() 121 for config in changed: 122 print_config("->", config, a[config], b[config]) 123 del b[config] 124 125 # now print items in b but not in a 126 # (items from b that were in a were removed above) 127 new = sorted(b.keys()) 128 for config in new: 129 print_config("+", config, None, b[config]) 130 131main() 132