kconfig: add diffconfig utility
Diffconfig is a simple utility for comparing two kernel configuration files.
See usage in the script for more info.
Signed-off-by: Tim Bird <tim.bird@am.sony.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
diff --git a/scripts/diffconfig b/scripts/diffconfig
new file mode 100755
index 0000000..b91f3e3
--- /dev/null
+++ b/scripts/diffconfig
@@ -0,0 +1,129 @@
+#!/usr/bin/python
+#
+# diffconfig - a tool to compare .config files.
+#
+# originally written in 2006 by Matt Mackall
+# (at least, this was in his bloatwatch source code)
+# last worked on 2008 by Tim Bird
+#
+
+import sys, os
+
+def usage():
+ print """Usage: diffconfig [-h] [-m] [<config1> <config2>]
+
+Diffconfig is a simple utility for comparing two .config files.
+Using standard diff to compare .config files often includes extraneous and
+distracting information. This utility produces sorted output with only the
+changes in configuration values between the two files.
+
+Added and removed items are shown with a leading plus or minus, respectively.
+Changed items show the old and new values on a single line.
+
+If -m is specified, then output will be in "merge" style, which has the
+changed and new values in kernel config option format.
+
+If no config files are specified, .config and .config.old are used.
+
+Example usage:
+ $ diffconfig .config config-with-some-changes
+-EXT2_FS_XATTR n
+-EXT2_FS_XIP n
+ CRAMFS n -> y
+ EXT2_FS y -> n
+ LOG_BUF_SHIFT 14 -> 16
+ PRINTK_TIME n -> y
+"""
+ sys.exit(0)
+
+# returns a dictionary of name/value pairs for config items in the file
+def readconfig(config_file):
+ d = {}
+ for line in config_file:
+ line = line[:-1]
+ if line[:7] == "CONFIG_":
+ name, val = line[7:].split("=", 1)
+ d[name] = val
+ if line[-11:] == " is not set":
+ d[line[9:-11]] = "n"
+ return d
+
+def print_config(op, config, value, new_value):
+ global merge_style
+
+ if merge_style:
+ if new_value:
+ if new_value=="n":
+ print "# CONFIG_%s is not set" % config
+ else:
+ print "CONFIG_%s=%s" % (config, new_value)
+ else:
+ if op=="-":
+ print "-%s %s" % (config, value)
+ elif op=="+":
+ print "+%s %s" % (config, new_value)
+ else:
+ print " %s %s -> %s" % (config, value, new_value)
+
+def main():
+ global merge_style
+
+ # parse command line args
+ if ("-h" in sys.argv or "--help" in sys.argv):
+ usage()
+
+ merge_style = 0
+ if "-m" in sys.argv:
+ merge_style = 1
+ sys.argv.remove("-m")
+
+ argc = len(sys.argv)
+ if not (argc==1 or argc == 3):
+ print "Error: incorrect number of arguments or unrecognized option"
+ usage()
+
+ if argc == 1:
+ # if no filenames given, assume .config and .config.old
+ build_dir=""
+ if os.environ.has_key("KBUILD_OUTPUT"):
+ build_dir = os.environ["KBUILD_OUTPUT"]+"/"
+
+ configa_filename = build_dir + ".config.old"
+ configb_filename = build_dir + ".config"
+ else:
+ configa_filename = sys.argv[1]
+ configb_filename = sys.argv[2]
+
+ a = readconfig(file(configa_filename))
+ b = readconfig(file(configb_filename))
+
+ # print items in a but not b (accumulate, sort and print)
+ old = []
+ for config in a:
+ if config not in b:
+ old.append(config)
+ old.sort()
+ for config in old:
+ print_config("-", config, a[config], None)
+ del a[config]
+
+ # print items that changed (accumulate, sort, and print)
+ changed = []
+ for config in a:
+ if a[config] != b[config]:
+ changed.append(config)
+ else:
+ del b[config]
+ changed.sort()
+ for config in changed:
+ print_config("->", config, a[config], b[config])
+ del b[config]
+
+ # now print items in b but not in a
+ # (items from b that were in a were removed above)
+ new = b.keys()
+ new.sort()
+ for config in new:
+ print_config("+", config, None, b[config])
+
+main()