#!/usr/bin/env python
# encoding: utf-8
# Thomas Nagy, 2006-2010 (ita)

"""
Dumb C/C++ preprocessor for finding dependencies

It will look at all include files it can find after removing the comments, so the following
will always add the dependency on both "a.h" and "b.h"::

	#include "a.h"
	#ifdef B
		#include "b.h"
	#endif
	int main() {
		return 0;
	}

To use::

	def configure(conf):
		conf.load('compiler_c')
		conf.load('c_dumbpreproc')
"""

import re, sys, os, string, traceback
from waflib import Logs, Build, Utils, Errors
from waflib.Logs import debug, error
from waflib.Tools import c_preproc

re_inc = re.compile(
	'^[ \t]*(#|%:)[ \t]*(include)[ \t]*[<"](.*)[>"][\r\t ]*$',
	re.IGNORECASE | re.MULTILINE)

def lines_includes(node):
	code = node.read()
	if c_preproc.use_trigraphs:
		for (a, b) in c_preproc.trig_def: code = code.split(a).join(b)
	code = c_preproc.re_nl.sub('', code)
	code = c_preproc.re_cpp.sub(c_preproc.repl, code)
	return [(m.group(2), m.group(3)) for m in re.finditer(re_inc, code)]

parser = c_preproc.c_parser
class dumb_parser(parser):
	def addlines(self, node):
		if node in self.nodes[:-1]:
			return
		self.currentnode_stack.append(node.parent)
		self.lines = lines_includes(node) + [(c_preproc.POPFILE, '')] +  self.lines

	def start(self, node, env):
		self.addlines(node)
		while self.lines:
			(x, y) = self.lines.pop(0)
			if x == c_preproc.POPFILE:
				self.currentnode_stack.pop()
				continue
			self.tryfind(y)

c_preproc.c_parser = dumb_parser