path: root/scripts/diffconfig (plain)
blob: 0db267d0adc9231de508b4cf9ca7068df8362384

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
10	import sys, os
11
12	def usage():
13	print("""Usage: diffconfig [-h] [-m] [<config1> <config2>]
14
15	Diffconfig is a simple utility for comparing two .config files.
16	Using standard diff to compare .config files often includes extraneous and
17	distracting information. This utility produces sorted output with only the
18	changes in configuration values between the two files.
19
20	Added and removed items are shown with a leading plus or minus, respectively.
21	Changed items show the old and new values on a single line.
22
23	If -m is specified, then output will be in "merge" style, which has the
24	changed and new values in kernel config option format.
25
26	If no config files are specified, .config and .config.old are used.
27
28	Example 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
39	def 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
50	def 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
67	def 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
131	main()
132