#!/usr/bin/python
import re
import os

class Kbuild:
	def __init__(self, root):
		self.root = root 
		self.confs = {}	# dict of lists
		self.modules = {}

		self.read_kbuild()

	def all_kbuild(self):
		cmd = 'find . '\
		      ' -regex "%s/[a-z].*/\\(Makefile\\|Kbuild\\)"' \
		      ' -not -regex ".*/\(' \
		      'arch\|Documents\|firmware\|scripts\|raid6test\)/.*"' \
		      % self.root
		return os.popen(cmd).read().split()

	def read_kbuild(self):
		allfile = [open(f).read() for f in self.all_kbuild()]
		data = "\n".join(allfile)
		data = re.sub(r"(?m)^ifeq\s+\(\$\((CONFIG_\S+)\s*\),\s*m\).*",
				r"obj-$(\1) \\", data)
		data = re.sub(r"(?m)\\\n\s*|obj-m ", '', data)
		all = re.findall( r"(?m)obj-\$\((CONFIG_\S+)\)\s*[:+]=(.*)", data)
		self.data = data
		for (conf, modules) in all:
			mods = re.findall(r"(\S+)\.o", modules)
			for m in mods:
				m = re.sub("-","_",m)
				#print conf, "->", m
				self.confs.setdefault(conf, []).append(m)
				self.modules.setdefault(m, []).append(conf)
	def read_modules(self):
		data = open("/proc/modules").read()
		return re.findall(r"(?m)^\S+", data)

	def test_module(self, m):
		all, conf = m.group(0,1)
		if conf in self.confs:
			return "# %s is not set"%conf
		return all

	def filter(self, config):
		#print self.data
		for m in self.read_modules():
			if not self.modules.has_key(m):
				print m,": Uknown module, may be firemware?"
				continue
			for c in self.modules[m]:
				if c in self.confs:
					del self.confs[c]
		data = open(config).read()
		data = re.sub(r"(?m)^(CONFIG_\S+)=m", self.test_module, data)
		out = config + ".min"
		print "Writing new config to:", out
		open(out, "w").write(data)
			
def main():
	kbuild = Kbuild(".")
	kbuild.filter(".config")
main()