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

"""
Tests for implementations of L{IReactorSocket}.

Generally only tests for failure cases are found here.  Success cases for
this interface are tested elsewhere.  For example, the success case for
I{AF_INET} is in L{twisted.internet.test.test_tcp}, since that case should
behave exactly the same as L{IReactorTCP.listenTCP}.
"""

import errno
import socket

from zope.interface import verify

from twisted.internet.error import UnsupportedAddressFamily
from twisted.internet.interfaces import IReactorSocket
from twisted.internet.protocol import DatagramProtocol, ServerFactory
from twisted.internet.test.reactormixins import ReactorBuilder, needsRunningReactor
from twisted.python.log import err
from twisted.python.runtime import platform


class IReactorSocketVerificationTestsBuilder(ReactorBuilder):
    """
    Builder for testing L{IReactorSocket} implementations for required
    methods and method signatures.

    L{ReactorBuilder} already runs L{IReactorSocket.providedBy} to
    ensure that these tests will only be run on reactor classes that
    claim to implement L{IReactorSocket}.

    These tests ensure that reactors which claim to provide the
    L{IReactorSocket} interface actually have all the required methods
    and that those methods have the expected number of arguments.

    These tests will be skipped for reactors which do not claim to
    provide L{IReactorSocket}.
    """

    requiredInterfaces = [IReactorSocket]

    def test_provider(self):
        """
        The reactor instance returned by C{buildReactor} provides
        L{IReactorSocket}.
        """
        reactor = self.buildReactor()
        self.assertTrue(verify.verifyObject(IReactorSocket, reactor))


class AdoptStreamPortErrorsTestsBuilder(ReactorBuilder):
    """
    Builder for testing L{IReactorSocket.adoptStreamPort} implementations.

    Generally only tests for failure cases are found here.  Success cases for
    this interface are tested elsewhere.  For example, the success case for
    I{AF_INET} is in L{twisted.internet.test.test_tcp}, since that case should
    behave exactly the same as L{IReactorTCP.listenTCP}.
    """

    requiredInterfaces = [IReactorSocket]

    def test_invalidDescriptor(self):
        """
        An implementation of L{IReactorSocket.adoptStreamPort} raises
        L{socket.error} if passed an integer which is not associated with a
        socket.
        """
        reactor = self.buildReactor()

        probe = socket.socket()
        fileno = probe.fileno()
        probe.close()

        exc = self.assertRaises(
            socket.error,
            reactor.adoptStreamPort,
            fileno,
            socket.AF_INET,
            ServerFactory(),
        )
        if platform.isWindows():
            self.assertEqual(exc.args[0], errno.WSAENOTSOCK)
        else:
            self.assertEqual(exc.args[0], errno.EBADF)

    def test_invalidAddressFamily(self):
        """
        An implementation of L{IReactorSocket.adoptStreamPort} raises
        L{UnsupportedAddressFamily} if passed an address family it does not
        support.
        """
        reactor = self.buildReactor()

        port = socket.socket()
        port.bind(("127.0.0.1", 0))
        port.listen(1)
        self.addCleanup(port.close)

        arbitrary = 2**16 + 7

        self.assertRaises(
            UnsupportedAddressFamily,
            reactor.adoptStreamPort,
            port.fileno(),
            arbitrary,
            ServerFactory(),
        )

    def test_stopOnlyCloses(self):
        """
        When the L{IListeningPort} returned by
        L{IReactorSocket.adoptStreamPort} is stopped using
        C{stopListening}, the underlying socket is closed but not
        shutdown.  This allows another process which still has a
        reference to it to continue accepting connections over it.
        """
        reactor = self.buildReactor()

        portSocket = socket.socket()
        self.addCleanup(portSocket.close)

        portSocket.bind(("127.0.0.1", 0))
        portSocket.listen(1)
        portSocket.setblocking(False)

        # The file descriptor is duplicated by adoptStreamPort
        port = reactor.adoptStreamPort(
            portSocket.fileno(), portSocket.family, ServerFactory()
        )
        d = port.stopListening()

        def stopped(ignored):
            # Should still be possible to accept a connection on
            # portSocket.  If it was shutdown, the exception would be
            # EINVAL instead.
            exc = self.assertRaises(socket.error, portSocket.accept)
            if platform.isWindows():
                self.assertEqual(exc.args[0], errno.WSAEWOULDBLOCK)
            else:
                self.assertEqual(exc.args[0], errno.EAGAIN)

        d.addCallback(stopped)
        d.addErrback(err, "Failed to accept on original port.")

        needsRunningReactor(
            reactor, lambda: d.addCallback(lambda ignored: reactor.stop())
        )

        reactor.run()


class AdoptStreamConnectionErrorsTestsBuilder(ReactorBuilder):
    """
    Builder for testing L{IReactorSocket.adoptStreamConnection}
    implementations.

    Generally only tests for failure cases are found here.  Success cases for
    this interface are tested elsewhere.  For example, the success case for
    I{AF_INET} is in L{twisted.internet.test.test_tcp}, since that case should
    behave exactly the same as L{IReactorTCP.listenTCP}.
    """

    requiredInterfaces = [IReactorSocket]

    def test_invalidAddressFamily(self):
        """
        An implementation of L{IReactorSocket.adoptStreamConnection} raises
        L{UnsupportedAddressFamily} if passed an address family it does not
        support.
        """
        reactor = self.buildReactor()

        connection = socket.socket()
        self.addCleanup(connection.close)

        arbitrary = 2**16 + 7

        self.assertRaises(
            UnsupportedAddressFamily,
            reactor.adoptStreamConnection,
            connection.fileno(),
            arbitrary,
            ServerFactory(),
        )


class AdoptDatagramPortErrorsTestsBuilder(ReactorBuilder):
    """
    Builder for testing L{IReactorSocket.adoptDatagramPort} implementations.
    """

    requiredInterfaces = [IReactorSocket]

    def test_invalidDescriptor(self):
        """
        An implementation of L{IReactorSocket.adoptDatagramPort} raises
        L{socket.error} if passed an integer which is not associated with a
        socket.
        """
        reactor = self.buildReactor()

        probe = socket.socket()
        fileno = probe.fileno()
        probe.close()

        exc = self.assertRaises(
            socket.error,
            reactor.adoptDatagramPort,
            fileno,
            socket.AF_INET,
            DatagramProtocol(),
        )
        if platform.isWindows():
            self.assertEqual(exc.args[0], errno.WSAENOTSOCK)
        else:
            self.assertEqual(exc.args[0], errno.EBADF)

    def test_invalidAddressFamily(self):
        """
        An implementation of L{IReactorSocket.adoptDatagramPort} raises
        L{UnsupportedAddressFamily} if passed an address family it does not
        support.
        """
        reactor = self.buildReactor()

        port = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
        self.addCleanup(port.close)

        arbitrary = 2**16 + 7

        self.assertRaises(
            UnsupportedAddressFamily,
            reactor.adoptDatagramPort,
            port.fileno(),
            arbitrary,
            DatagramProtocol(),
        )

    def test_stopOnlyCloses(self):
        """
        When the L{IListeningPort} returned by
        L{IReactorSocket.adoptDatagramPort} is stopped using
        C{stopListening}, the underlying socket is closed but not
        shutdown.  This allows another process which still has a
        reference to it to continue reading and writing to it.
        """
        reactor = self.buildReactor()

        portSocket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
        self.addCleanup(portSocket.close)

        portSocket.bind(("127.0.0.1", 0))
        portSocket.setblocking(False)

        # The file descriptor is duplicated by adoptDatagramPort
        port = reactor.adoptDatagramPort(
            portSocket.fileno(), portSocket.family, DatagramProtocol()
        )
        d = port.stopListening()

        def stopped(ignored):
            # Should still be possible to recv on portSocket.  If
            # it was shutdown, the exception would be EINVAL instead.
            exc = self.assertRaises(socket.error, portSocket.recvfrom, 1)
            if platform.isWindows():
                self.assertEqual(exc.args[0], errno.WSAEWOULDBLOCK)
            else:
                self.assertEqual(exc.args[0], errno.EAGAIN)

        d.addCallback(stopped)
        d.addErrback(err, "Failed to read on original port.")

        needsRunningReactor(
            reactor, lambda: d.addCallback(lambda ignored: reactor.stop())
        )

        reactor.run()


globals().update(IReactorSocketVerificationTestsBuilder.makeTestCaseClasses())
globals().update(AdoptStreamPortErrorsTestsBuilder.makeTestCaseClasses())
globals().update(AdoptStreamConnectionErrorsTestsBuilder.makeTestCaseClasses())
globals().update(AdoptDatagramPortErrorsTestsBuilder.makeTestCaseClasses())