# Copyright (c) Twisted Matrix Laboratories.
# See LICENSE for details.

"""
Tests for L{twisted.internet.iocpreactor}.
"""

import errno
from array import array
from struct import pack
from socket import AF_INET6, AF_INET, SOCK_STREAM, SOL_SOCKET, error, socket

from zope.interface.verify import verifyClass

from twisted.trial import unittest
from twisted.python.log import msg
from twisted.internet.interfaces import IPushProducer

try:
from twisted.internet.iocpreactor import iocpsupport as _iocp, tcp, udp
from twisted.internet.iocpreactor.reactor import IOCPReactor, EVENTS_PER_LOOP, KEY_NORMAL
from twisted.internet.iocpreactor.interfaces import IReadWriteHandle
from twisted.internet.iocpreactor.const import SO_UPDATE_ACCEPT_CONTEXT
from twisted.internet.iocpreactor.abstract import FileHandle
except ImportError:
skip = 'This test only applies to IOCPReactor'

try:
socket(AF_INET6, SOCK_STREAM).close()
except error, e:
ipv6Skip = str(e)
else:
ipv6Skip = None

class SupportTests(unittest.TestCase):
"""
Tests for L{twisted.internet.iocpreactor.iocpsupport}, low-level reactor
implementation helpers.
"""
def _acceptAddressTest(self, family, localhost):
"""
Create a C{SOCK_STREAM} connection to localhost using a socket with an
address family of C{family} and assert that the result of
L{iocpsupport.get_accept_addrs} is consistent with the result of
C{socket.getsockname} and C{socket.getpeername}.
"""
msg("family = %r" % (family,))
port = socket(family, SOCK_STREAM)
self.addCleanup(port.close)
port.bind(('', 0))
port.listen(1)
client = socket(family, SOCK_STREAM)
self.addCleanup(client.close)
client.setblocking(False)
try:
client.connect((localhost, port.getsockname()[1]))
except error, (errnum, message):
self.assertIn(errnum, (errno.EINPROGRESS, errno.EWOULDBLOCK))

server = socket(family, SOCK_STREAM)
self.addCleanup(server.close)
buff = array('c', '\0' * 256)
self.assertEqual(
0, _iocp.accept(port.fileno(), server.fileno(), buff, None))
server.setsockopt(
SOL_SOCKET, SO_UPDATE_ACCEPT_CONTEXT, pack('P', server.fileno()))
self.assertEqual(
(family, client.getpeername()[:2], client.getsockname()[:2]),
_iocp.get_accept_addrs(server.fileno(), buff))


def test_ipv4AcceptAddress(self):
"""
L{iocpsupport.get_accept_addrs} returns a three-tuple of address
information about the socket associated with the file descriptor passed
to it. For a connection using IPv4:

- the first element is C{AF_INET}
- the second element is a two-tuple of a dotted decimal notation IPv4
address and a port number giving the peer address of the connection
- the third element is the same type giving the host address of the
connection
"""
self._acceptAddressTest(AF_INET, '127.0.0.1')


def test_ipv6AcceptAddress(self):
"""
Like L{test_ipv4AcceptAddress}, but for IPv6 connections. In this case:

- the first element is C{AF_INET6}
- the second element is a two-tuple of a hexadecimal IPv6 address
literal and a port number giving the peer address of the connection
- the third element is the same type giving the host address of the
connection
"""
self._acceptAddressTest(AF_INET6, '::1')
if ipv6Skip is not None:
test_ipv6AcceptAddress.skip = ipv6Skip



class IOCPReactorTestCase(unittest.TestCase):
def test_noPendingTimerEvents(self):
"""
Test reactor behavior (doIteration) when there are no pending time
events.
"""
ir = IOCPReactor()
ir.wakeUp()
self.assertFalse(ir.doIteration(None))


def test_reactorInterfaces(self):
"""
Verify that IOCP socket-representing classes implement IReadWriteHandle
"""
self.assertTrue(verifyClass(IReadWriteHandle, tcp.Connection))
self.assertTrue(verifyClass(IReadWriteHandle, udp.Port))


def test_fileHandleInterfaces(self):
"""
Verify that L{Filehandle} implements L{IPushProducer}.
"""
self.assertTrue(verifyClass(IPushProducer, FileHandle))


def test_maxEventsPerIteration(self):
"""
Verify that we don't lose an event when more than EVENTS_PER_LOOP
events occur in the same reactor iteration
"""
class FakeFD:
counter = 0
def logPrefix(self):
return 'FakeFD'
def cb(self, rc, bytes, evt):
self.counter += 1

ir = IOCPReactor()
fd = FakeFD()
event = _iocp.Event(fd.cb, fd)
for _ in range(EVENTS_PER_LOOP + 1):
ir.port.postEvent(0, KEY_NORMAL, event)
ir.doIteration(None)
self.assertEqual(fd.counter, EVENTS_PER_LOOP)
ir.doIteration(0)
self.assertEqual(fd.counter, EVENTS_PER_LOOP + 1)