add diffconfig utility

@@ -0,0 +1,90 @@
+#!/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)
+#
+# 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.
+#
+# Example usage:
+# $ diffconfig .config config-test-nfs-off
+# -LOCKD  y
+# -LOCKD_V4  y
+# -NFS_COMMON  y
+# -NFS_DIRECTIO  n
+# -NFS_V3  y
+# -NFS_V3_ACL  n
+# -NFS_V4  n
+# -ROOT_NFS  y
+# -RPCSEC_GSS_KRB5  n
+# -RPCSEC_GSS_SPKM3  n
+# -SUNRPC  y
+# -SUNRPC_BIND34  n
+#  NFS_FS  y -> n
+
+import sys, os
+
+if len(sys.argv) < 3:
+	print "Usage: diffconfig <config1> <config2>"
+	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
+
+a = readconfig(file(sys.argv[1]))
+b = readconfig(file(sys.argv[2]))
+
+# 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 "-%s  %s" % (config, a[config])
+    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 " %s  %s -> %s" % (config, a[config], b[config])
+    del b[config]
+
+# now print items in b but not in a
+
+# the items from b that were in a (either the same or that changed) were removed
+# the only items left were not in a
+new = b.keys()
+
+new.sort()
+
+for config in new:
+    print "+%s  %s" % (config, b[config])

new file mode 100755
index 0000000..aa6cfe1
@@ -0,0 +1,108 @@
+#!/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
+
+merge_style = 0
+if "-m" in sys.argv:
+    merge_style = 1
+    sys.argv.remove("-m")
+
+if "-h" in sys.argv or len(sys.argv) < 3:
+    print "Usage: diffconfig [-h] [-m] <config1> <config2>\n"
+    print """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.
+
+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
+
+a = readconfig(file(sys.argv[1]))
+b = readconfig(file(sys.argv[2]))
+
+def print_config(op, config, value, new_value):
+    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)
+
+# 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
+
+# the items from b that were in a (either the same or that changed) were removed
+# the only items left were not in a
+new = b.keys()
+
+new.sort()
+
+for config in new:
+    print_config("+", config, None, b[config])

new file mode 100755
index 0000000..aa6cfe1
@@ -0,0 +1,128 @@
+#!/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>]\n"
+    print """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()

new file mode 100755
index 0000000..aa6cfe1
@@ -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()