blob: b91f3e34d44d5d39907b8bbef3de4fb6f37fbb69 [file] [log] [blame]
Tim Birda7174172008-06-24 10:56:06 -07001#!/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-EXT2_FS_XIP n
32 CRAMFS n -> y
33 EXT2_FS y -> n
34 LOG_BUF_SHIFT 14 -> 16
35 PRINTK_TIME n -> y
36"""
37 sys.exit(0)
38
39# returns a dictionary of name/value pairs for config items in the file
40def readconfig(config_file):
41 d = {}
42 for line in config_file:
43 line = line[:-1]
44 if line[:7] == "CONFIG_":
45 name, val = line[7:].split("=", 1)
46 d[name] = val
47 if line[-11:] == " is not set":
48 d[line[9:-11]] = "n"
49 return d
50
51def print_config(op, config, value, new_value):
52 global merge_style
53
54 if merge_style:
55 if new_value:
56 if new_value=="n":
57 print "# CONFIG_%s is not set" % config
58 else:
59 print "CONFIG_%s=%s" % (config, new_value)
60 else:
61 if op=="-":
62 print "-%s %s" % (config, value)
63 elif op=="+":
64 print "+%s %s" % (config, new_value)
65 else:
66 print " %s %s -> %s" % (config, value, new_value)
67
68def main():
69 global merge_style
70
71 # parse command line args
72 if ("-h" in sys.argv or "--help" in sys.argv):
73 usage()
74
75 merge_style = 0
76 if "-m" in sys.argv:
77 merge_style = 1
78 sys.argv.remove("-m")
79
80 argc = len(sys.argv)
81 if not (argc==1 or argc == 3):
82 print "Error: incorrect number of arguments or unrecognized option"
83 usage()
84
85 if argc == 1:
86 # if no filenames given, assume .config and .config.old
87 build_dir=""
88 if os.environ.has_key("KBUILD_OUTPUT"):
89 build_dir = os.environ["KBUILD_OUTPUT"]+"/"
90
91 configa_filename = build_dir + ".config.old"
92 configb_filename = build_dir + ".config"
93 else:
94 configa_filename = sys.argv[1]
95 configb_filename = sys.argv[2]
96
97 a = readconfig(file(configa_filename))
98 b = readconfig(file(configb_filename))
99
100 # print items in a but not b (accumulate, sort and print)
101 old = []
102 for config in a:
103 if config not in b:
104 old.append(config)
105 old.sort()
106 for config in old:
107 print_config("-", config, a[config], None)
108 del a[config]
109
110 # print items that changed (accumulate, sort, and print)
111 changed = []
112 for config in a:
113 if a[config] != b[config]:
114 changed.append(config)
115 else:
116 del b[config]
117 changed.sort()
118 for config in changed:
119 print_config("->", config, a[config], b[config])
120 del b[config]
121
122 # now print items in b but not in a
123 # (items from b that were in a were removed above)
124 new = b.keys()
125 new.sort()
126 for config in new:
127 print_config("+", config, None, b[config])
128
129main()