Merged revisions 64104,64117 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/trunk

........
  r64104 | benjamin.peterson | 2008-06-10 21:40:25 -0500 (Tue, 10 Jun 2008) | 2 lines

  add the multiprocessing package to fulfill PEP 371
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  r64117 | benjamin.peterson | 2008-06-11 07:26:31 -0500 (Wed, 11 Jun 2008) | 2 lines

  fix import of multiprocessing by juggling imports
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diff --git a/Lib/multiprocessing/connection.py b/Lib/multiprocessing/connection.py
new file mode 100644
index 0000000..27c44cd
--- /dev/null
+++ b/Lib/multiprocessing/connection.py
@@ -0,0 +1,425 @@
+#
+# A higher level module for using sockets (or Windows named pipes)
+#
+# multiprocessing/connection.py
+#
+# Copyright (c) 2006-2008, R Oudkerk --- see COPYING.txt
+#
+
+__all__ = [ 'Client', 'Listener', 'Pipe' ]
+
+import os
+import sys
+import socket
+import time
+import tempfile
+import itertools
+
+import _multiprocessing
+from multiprocessing import current_process
+from multiprocessing.util import get_temp_dir, Finalize, sub_debug, debug
+from multiprocessing.forking import duplicate, close
+
+
+#
+#
+#
+
+BUFSIZE = 8192
+
+_mmap_counter = itertools.count()
+
+default_family = 'AF_INET'
+families = ['AF_INET']
+
+if hasattr(socket, 'AF_UNIX'):
+    default_family = 'AF_UNIX'
+    families += ['AF_UNIX']
+
+if sys.platform == 'win32':
+    default_family = 'AF_PIPE'
+    families += ['AF_PIPE']
+
+#
+#
+#
+
+def arbitrary_address(family):
+    '''
+    Return an arbitrary free address for the given family
+    '''
+    if family == 'AF_INET':
+        return ('localhost', 0)
+    elif family == 'AF_UNIX':
+        return tempfile.mktemp(prefix='listener-', dir=get_temp_dir())
+    elif family == 'AF_PIPE':
+        return tempfile.mktemp(prefix=r'\\.\pipe\pyc-%d-%d-' %
+                               (os.getpid(), next(_mmap_counter)))
+    else:
+        raise ValueError('unrecognized family')
+
+
+def address_type(address):
+    '''
+    Return the types of the address
+
+    This can be 'AF_INET', 'AF_UNIX', or 'AF_PIPE'
+    '''
+    if type(address) == tuple:
+        return 'AF_INET'
+    elif type(address) is str and address.startswith('\\\\'):
+        return 'AF_PIPE'
+    elif type(address) is str:
+        return 'AF_UNIX'
+    else:
+        raise ValueError('address type of %r unrecognized' % address)
+
+#
+# Public functions
+#
+
+class Listener(object):
+    '''
+    Returns a listener object.
+
+    This is a wrapper for a bound socket which is 'listening' for
+    connections, or for a Windows named pipe.
+    '''
+    def __init__(self, address=None, family=None, backlog=1, authkey=None):
+        family = family or (address and address_type(address)) \
+                 or default_family
+        address = address or arbitrary_address(family)
+
+        if family == 'AF_PIPE':
+            self._listener = PipeListener(address, backlog)
+        else:
+            self._listener = SocketListener(address, family, backlog)
+
+        if authkey is not None and not isinstance(authkey, bytes):
+            raise TypeError('authkey should be a byte string')
+
+        self._authkey = authkey
+
+    def accept(self):
+        '''
+        Accept a connection on the bound socket or named pipe of `self`.
+
+        Returns a `Connection` object.
+        '''
+        c = self._listener.accept()
+        if self._authkey:
+            deliver_challenge(c, self._authkey)
+            answer_challenge(c, self._authkey)
+        return c
+
+    def close(self):
+        '''
+        Close the bound socket or named pipe of `self`.
+        '''
+        return self._listener.close()
+
+    address = property(lambda self: self._listener._address)
+    last_accepted = property(lambda self: self._listener._last_accepted)
+
+
+def Client(address, family=None, authkey=None):
+    '''
+    Returns a connection to the address of a `Listener`
+    '''
+    family = family or address_type(address)
+    if family == 'AF_PIPE':
+        c = PipeClient(address)
+    else:
+        c = SocketClient(address)
+
+    if authkey is not None and not isinstance(authkey, bytes):
+        raise TypeError('authkey should be a byte string')
+
+    if authkey is not None:
+        answer_challenge(c, authkey)
+        deliver_challenge(c, authkey)
+
+    return c
+
+
+if sys.platform != 'win32':
+
+    def Pipe(duplex=True):
+        '''
+        Returns pair of connection objects at either end of a pipe
+        '''
+        if duplex:
+            s1, s2 = socket.socketpair()
+            c1 = _multiprocessing.Connection(os.dup(s1.fileno()))
+            c2 = _multiprocessing.Connection(os.dup(s2.fileno()))
+            s1.close()
+            s2.close()
+        else:
+            fd1, fd2 = os.pipe()
+            c1 = _multiprocessing.Connection(fd1, writable=False)
+            c2 = _multiprocessing.Connection(fd2, readable=False)
+
+        return c1, c2
+
+else:
+
+    from ._multiprocessing import win32
+
+    def Pipe(duplex=True):
+        '''
+        Returns pair of connection objects at either end of a pipe
+        '''
+        address = arbitrary_address('AF_PIPE')
+        if duplex:
+            openmode = win32.PIPE_ACCESS_DUPLEX
+            access = win32.GENERIC_READ | win32.GENERIC_WRITE
+            obsize, ibsize = BUFSIZE, BUFSIZE
+        else:
+            openmode = win32.PIPE_ACCESS_INBOUND
+            access = win32.GENERIC_WRITE
+            obsize, ibsize = 0, BUFSIZE
+
+        h1 = win32.CreateNamedPipe(
+            address, openmode,
+            win32.PIPE_TYPE_MESSAGE | win32.PIPE_READMODE_MESSAGE |
+            win32.PIPE_WAIT,
+            1, obsize, ibsize, win32.NMPWAIT_WAIT_FOREVER, win32.NULL
+            )
+        h2 = win32.CreateFile(
+            address, access, 0, win32.NULL, win32.OPEN_EXISTING, 0, win32.NULL
+            )
+        win32.SetNamedPipeHandleState(
+            h2, win32.PIPE_READMODE_MESSAGE, None, None
+            )
+
+        try:
+            win32.ConnectNamedPipe(h1, win32.NULL)
+        except WindowsError as e:
+            if e.args[0] != win32.ERROR_PIPE_CONNECTED:
+                raise
+
+        c1 = _multiprocessing.PipeConnection(h1, writable=duplex)
+        c2 = _multiprocessing.PipeConnection(h2, readable=duplex)
+
+        return c1, c2
+
+#
+# Definitions for connections based on sockets
+#
+
+class SocketListener(object):
+    '''
+    Represtation of a socket which is bound to an address and listening
+    '''
+    def __init__(self, address, family, backlog=1):
+        self._socket = socket.socket(getattr(socket, family))
+        self._socket.bind(address)
+        self._socket.listen(backlog)
+        address = self._socket.getsockname()
+        if type(address) is tuple:
+            address = (socket.getfqdn(address[0]),) + address[1:]
+        self._address = address
+        self._family = family
+        self._last_accepted = None
+
+        sub_debug('listener bound to address %r', self._address)
+
+        if family == 'AF_UNIX':
+            self._unlink = Finalize(
+                self, os.unlink, args=(self._address,), exitpriority=0
+                )
+        else:
+            self._unlink = None
+
+    def accept(self):
+        s, self._last_accepted = self._socket.accept()
+        fd = duplicate(s.fileno())
+        conn = _multiprocessing.Connection(fd)
+        s.close()
+        return conn
+
+    def close(self):
+        self._socket.close()
+        if self._unlink is not None:
+            self._unlink()
+
+
+def SocketClient(address):
+    '''
+    Return a connection object connected to the socket given by `address`
+    '''
+    family = address_type(address)
+    s = socket.socket( getattr(socket, family) )
+
+    while 1:
+        try:
+            s.connect(address)
+        except socket.error as e:
+            if e.args[0] != 10061:    # 10061 => connection refused
+                debug('failed to connect to address %s', address)
+                raise
+            time.sleep(0.01)
+        else:
+            break
+    else:
+        raise
+
+    fd = duplicate(s.fileno())
+    conn = _multiprocessing.Connection(fd)
+    s.close()
+    return conn
+
+#
+# Definitions for connections based on named pipes
+#
+
+if sys.platform == 'win32':
+
+    class PipeListener(object):
+        '''
+        Representation of a named pipe
+        '''
+        def __init__(self, address, backlog=None):
+            self._address = address
+            handle = win32.CreateNamedPipe(
+                address, win32.PIPE_ACCESS_DUPLEX,
+                win32.PIPE_TYPE_MESSAGE | win32.PIPE_READMODE_MESSAGE |
+                win32.PIPE_WAIT,
+                win32.PIPE_UNLIMITED_INSTANCES, BUFSIZE, BUFSIZE,
+                win32.NMPWAIT_WAIT_FOREVER, win32.NULL
+                )
+            self._handle_queue = [handle]
+            self._last_accepted = None
+
+            sub_debug('listener created with address=%r', self._address)
+
+            self.close = Finalize(
+                self, PipeListener._finalize_pipe_listener,
+                args=(self._handle_queue, self._address), exitpriority=0
+                )
+
+        def accept(self):
+            newhandle = win32.CreateNamedPipe(
+                self._address, win32.PIPE_ACCESS_DUPLEX,
+                win32.PIPE_TYPE_MESSAGE | win32.PIPE_READMODE_MESSAGE |
+                win32.PIPE_WAIT,
+                win32.PIPE_UNLIMITED_INSTANCES, BUFSIZE, BUFSIZE,
+                win32.NMPWAIT_WAIT_FOREVER, win32.NULL
+                )
+            self._handle_queue.append(newhandle)
+            handle = self._handle_queue.pop(0)
+            try:
+                win32.ConnectNamedPipe(handle, win32.NULL)
+            except WindowsError as e:
+                if e.args[0] != win32.ERROR_PIPE_CONNECTED:
+                    raise
+            return _multiprocessing.PipeConnection(handle)
+
+        @staticmethod
+        def _finalize_pipe_listener(queue, address):
+            sub_debug('closing listener with address=%r', address)
+            for handle in queue:
+                close(handle)
+
+    def PipeClient(address):
+        '''
+        Return a connection object connected to the pipe given by `address`
+        '''
+        while 1:
+            try:
+                win32.WaitNamedPipe(address, 1000)
+                h = win32.CreateFile(
+                    address, win32.GENERIC_READ | win32.GENERIC_WRITE,
+                    0, win32.NULL, win32.OPEN_EXISTING, 0, win32.NULL
+                    )
+            except WindowsError as e:
+                if e.args[0] not in (win32.ERROR_SEM_TIMEOUT,
+                                     win32.ERROR_PIPE_BUSY):
+                    raise
+            else:
+                break
+        else:
+            raise
+
+        win32.SetNamedPipeHandleState(
+            h, win32.PIPE_READMODE_MESSAGE, None, None
+            )
+        return _multiprocessing.PipeConnection(h)
+
+#
+# Authentication stuff
+#
+
+MESSAGE_LENGTH = 20
+
+CHALLENGE = '#CHALLENGE#'
+WELCOME = '#WELCOME#'
+FAILURE = '#FAILURE#'
+
+if sys.version_info >= (3, 0):         # XXX can use bytes literals in 2.6/3.0
+    CHALLENGE = CHALLENGE.encode('ascii')
+    WELCOME = WELCOME.encode('ascii')
+    FAILURE = FAILURE.encode('ascii')
+
+def deliver_challenge(connection, authkey):
+    import hmac
+    assert isinstance(authkey, bytes)
+    message = os.urandom(MESSAGE_LENGTH)
+    connection.send_bytes(CHALLENGE + message)
+    digest = hmac.new(authkey, message).digest()
+    response = connection.recv_bytes(256)        # reject large message
+    if response == digest:
+        connection.send_bytes(WELCOME)
+    else:
+        connection.send_bytes(FAILURE)
+        raise AuthenticationError('digest received was wrong')
+
+def answer_challenge(connection, authkey):
+    import hmac
+    assert isinstance(authkey, bytes)
+    message = connection.recv_bytes(256)         # reject large message
+    assert message[:len(CHALLENGE)] == CHALLENGE, 'message = %r' % message
+    message = message[len(CHALLENGE):]
+    digest = hmac.new(authkey, message).digest()
+    connection.send_bytes(digest)
+    response = connection.recv_bytes(256)        # reject large message
+    if response != WELCOME:
+        raise AuthenticationError('digest sent was rejected')
+
+#
+# Support for using xmlrpclib for serialization
+#
+
+class ConnectionWrapper(object):
+    def __init__(self, conn, dumps, loads):
+        self._conn = conn
+        self._dumps = dumps
+        self._loads = loads
+        for attr in ('fileno', 'close', 'poll', 'recv_bytes', 'send_bytes'):
+            obj = getattr(conn, attr)
+            setattr(self, attr, obj)
+    def send(self, obj):
+        s = self._dumps(obj)
+        self._conn.send_bytes(s)
+    def recv(self):
+        s = self._conn.recv_bytes()
+        return self._loads(s)
+
+def _xml_dumps(obj):
+    return xmlrpclib.dumps((obj,), None, None, None, 1).encode('utf8')
+
+def _xml_loads(s):
+    (obj,), method = xmlrpclib.loads(s.decode('utf8'))
+    return obj
+
+class XmlListener(Listener):
+    def accept(self):
+        global xmlrpclib
+        import xmlrpc.client as xmlrpclib
+        obj = Listener.accept(self)
+        return ConnectionWrapper(obj, _xml_dumps, _xml_loads)
+
+def XmlClient(*args, **kwds):
+    global xmlrpclib
+    import xmlrpc.client as xmlrpclib
+    return ConnectionWrapper(Client(*args, **kwds), _xml_dumps, _xml_loads)