#!/usr/bin/env python

# Test should cause segfault on Linux i386 Python 2.7.3 - 2.7.4

from __future__ import print_function

import sys
import xml.parsers.expat

def start_element(name, attrs):
	pass

def end_element(name):
	pass

def char_data(data):
	pass

ep = None

def instantiate_parser():
	"""Create an Expat parser instance (intended for re-use across multiple
	calls to its Parse() method) and attach generic delegate methods."""

	global ep

	try:
		ep = xml.parsers.expat.ParserCreate()

		ep.StartElementHandler = start_element
		ep.EndElementHandler = end_element
		ep.CharacterDataHandler = char_data

	except xml.parsers.expat.ExpatError as error:
		print("An error occurred during Expat set-up.  " \
			  + "Error ID: " + str(error.code) \
			  + ".  Error message: " \
			  + xml.parsers.expat.ErrorString(error.code), file=sys.stderr)

# We're not actually using this function since we'll crash before it
# gets called...
def destroy_parser():
	"""Invoke a final call to the Expat parser's Parse() method to pass the
	IsFinal value of True so it will destroy itself."""

	global ep

	if ep != None:
		try:
			ep.Parse('', True)
		except xml.parsers.expat.ExpatError as error:
			print("An error occurred during XML parsing.  " \
				+ "Error ID: " + str(error.code) \
				+ ".  Error message: " \
				+ xml.parsers.expat.ErrorString(error.code), file=sys.stderr)
		finally:
			ep = None

def parse_doc(input_string):
	"""Accepts a string representing relevant data from an XML file and
	initiates the extraction of relevant data via proxy methods."""

	global ep

	if ep == None:
		instantiate_parser()

	try:
		ep.Parse(input_string, False)
	except xml.parsers.expat.ExpatError as error:
		print("An error occurred during XML parsing.  " \
			  + "Error ID: " + str(error.code) \
			  + ".  Error message: " \
			  + xml.parsers.expat.ErrorString(error.code), file=sys.stderr)
		print("Line number:", ep.ErrorLineNumber, file=sys.stderr)

small_test_file = \
"""<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<foobar>
  <foo>777</foo>
  <bar>443></bar>
</foobar>"""


data_size = 248174

large_test_file = \
  '<?xml version="1.0" encoding="UTF-8" standalone="yes"?>' \
  + "\n<footwo>\n" \
  + "<foo>1234</foo>\n" * data_size \
  + '</footwo>'

if __name__ == "__main__":
	def lol():
		parse_doc(small_test_file)  # Initial, successful parse
		parse_doc(small_test_file)  # First triggering of a parser error
		parse_doc(large_test_file)  # Subsequent parser error, with more data
		destroy_parser()
	import threading
	for i in xrange(85):
		threading.Thread(target=lol).start()