add hg and python

sys/lib/python/idlelib/rpc.py

@@ -0,0 +1,602 @@
+"""RPC Implemention, originally written for the Python Idle IDE
+
+For security reasons, GvR requested that Idle's Python execution server process
+connect to the Idle process, which listens for the connection.  Since Idle has
+has only one client per server, this was not a limitation.
+
+   +---------------------------------+ +-------------+
+   | SocketServer.BaseRequestHandler | | SocketIO    |
+   +---------------------------------+ +-------------+
+                   ^                   | register()  |
+                   |                   | unregister()|
+                   |                   +-------------+
+                   |                      ^  ^
+                   |                      |  |
+                   | + -------------------+  |
+                   | |                       |
+   +-------------------------+        +-----------------+
+   | RPCHandler              |        | RPCClient       |
+   | [attribute of RPCServer]|        |                 |
+   +-------------------------+        +-----------------+
+
+The RPCServer handler class is expected to provide register/unregister methods.
+RPCHandler inherits the mix-in class SocketIO, which provides these methods.
+
+See the Idle run.main() docstring for further information on how this was
+accomplished in Idle.
+
+"""
+
+import sys
+import os
+import socket
+import select
+import SocketServer
+import struct
+import cPickle as pickle
+import threading
+import Queue
+import traceback
+import copy_reg
+import types
+import marshal
+
+
+def unpickle_code(ms):
+    co = marshal.loads(ms)
+    assert isinstance(co, types.CodeType)
+    return co
+
+def pickle_code(co):
+    assert isinstance(co, types.CodeType)
+    ms = marshal.dumps(co)
+    return unpickle_code, (ms,)
+
+# XXX KBK 24Aug02 function pickling capability not used in Idle
+#  def unpickle_function(ms):
+#      return ms
+
+#  def pickle_function(fn):
+#      assert isinstance(fn, type.FunctionType)
+#      return repr(fn)
+
+copy_reg.pickle(types.CodeType, pickle_code, unpickle_code)
+# copy_reg.pickle(types.FunctionType, pickle_function, unpickle_function)
+
+BUFSIZE = 8*1024
+LOCALHOST = '127.0.0.1'
+
+class RPCServer(SocketServer.TCPServer):
+
+    def __init__(self, addr, handlerclass=None):
+        if handlerclass is None:
+            handlerclass = RPCHandler
+        SocketServer.TCPServer.__init__(self, addr, handlerclass)
+
+    def server_bind(self):
+        "Override TCPServer method, no bind() phase for connecting entity"
+        pass
+
+    def server_activate(self):
+        """Override TCPServer method, connect() instead of listen()
+
+        Due to the reversed connection, self.server_address is actually the
+        address of the Idle Client to which we are connecting.
+
+        """
+        self.socket.connect(self.server_address)
+
+    def get_request(self):
+        "Override TCPServer method, return already connected socket"
+        return self.socket, self.server_address
+
+    def handle_error(self, request, client_address):
+        """Override TCPServer method
+
+        Error message goes to __stderr__.  No error message if exiting
+        normally or socket raised EOF.  Other exceptions not handled in
+        server code will cause os._exit.
+
+        """
+        try:
+            raise
+        except SystemExit:
+            raise
+        except:
+            erf = sys.__stderr__
+            print>>erf, '\n' + '-'*40
+            print>>erf, 'Unhandled server exception!'
+            print>>erf, 'Thread: %s' % threading.currentThread().getName()
+            print>>erf, 'Client Address: ', client_address
+            print>>erf, 'Request: ', repr(request)
+            traceback.print_exc(file=erf)
+            print>>erf, '\n*** Unrecoverable, server exiting!'
+            print>>erf, '-'*40
+            os._exit(0)
+
+#----------------- end class RPCServer --------------------
+
+objecttable = {}
+request_queue = Queue.Queue(0)
+response_queue = Queue.Queue(0)
+
+
+class SocketIO(object):
+
+    nextseq = 0
+
+    def __init__(self, sock, objtable=None, debugging=None):
+        self.sockthread = threading.currentThread()
+        if debugging is not None:
+            self.debugging = debugging
+        self.sock = sock
+        if objtable is None:
+            objtable = objecttable
+        self.objtable = objtable
+        self.responses = {}
+        self.cvars = {}
+
+    def close(self):
+        sock = self.sock
+        self.sock = None
+        if sock is not None:
+            sock.close()
+
+    def exithook(self):
+        "override for specific exit action"
+        os._exit()
+
+    def debug(self, *args):
+        if not self.debugging:
+            return
+        s = self.location + " " + str(threading.currentThread().getName())
+        for a in args:
+            s = s + " " + str(a)
+        print>>sys.__stderr__, s
+
+    def register(self, oid, object):
+        self.objtable[oid] = object
+
+    def unregister(self, oid):
+        try:
+            del self.objtable[oid]
+        except KeyError:
+            pass
+
+    def localcall(self, seq, request):
+        self.debug("localcall:", request)
+        try:
+            how, (oid, methodname, args, kwargs) = request
+        except TypeError:
+            return ("ERROR", "Bad request format")
+        if not self.objtable.has_key(oid):
+            return ("ERROR", "Unknown object id: %r" % (oid,))
+        obj = self.objtable[oid]
+        if methodname == "__methods__":
+            methods = {}
+            _getmethods(obj, methods)
+            return ("OK", methods)
+        if methodname == "__attributes__":
+            attributes = {}
+            _getattributes(obj, attributes)
+            return ("OK", attributes)
+        if not hasattr(obj, methodname):
+            return ("ERROR", "Unsupported method name: %r" % (methodname,))
+        method = getattr(obj, methodname)
+        try:
+            if how == 'CALL':
+                ret = method(*args, **kwargs)
+                if isinstance(ret, RemoteObject):
+                    ret = remoteref(ret)
+                return ("OK", ret)
+            elif how == 'QUEUE':
+                request_queue.put((seq, (method, args, kwargs)))
+                return("QUEUED", None)
+            else:
+                return ("ERROR", "Unsupported message type: %s" % how)
+        except SystemExit:
+            raise
+        except socket.error:
+            raise
+        except:
+            msg = "*** Internal Error: rpc.py:SocketIO.localcall()\n\n"\
+                  " Object: %s \n Method: %s \n Args: %s\n"
+            print>>sys.__stderr__, msg % (oid, method, args)
+            traceback.print_exc(file=sys.__stderr__)
+            return ("EXCEPTION", None)
+
+    def remotecall(self, oid, methodname, args, kwargs):
+        self.debug("remotecall:asynccall: ", oid, methodname)
+        seq = self.asynccall(oid, methodname, args, kwargs)
+        return self.asyncreturn(seq)
+
+    def remotequeue(self, oid, methodname, args, kwargs):
+        self.debug("remotequeue:asyncqueue: ", oid, methodname)
+        seq = self.asyncqueue(oid, methodname, args, kwargs)
+        return self.asyncreturn(seq)
+
+    def asynccall(self, oid, methodname, args, kwargs):
+        request = ("CALL", (oid, methodname, args, kwargs))
+        seq = self.newseq()
+        if threading.currentThread() != self.sockthread:
+            cvar = threading.Condition()
+            self.cvars[seq] = cvar
+        self.debug(("asynccall:%d:" % seq), oid, methodname, args, kwargs)
+        self.putmessage((seq, request))
+        return seq
+
+    def asyncqueue(self, oid, methodname, args, kwargs):
+        request = ("QUEUE", (oid, methodname, args, kwargs))
+        seq = self.newseq()
+        if threading.currentThread() != self.sockthread:
+            cvar = threading.Condition()
+            self.cvars[seq] = cvar
+        self.debug(("asyncqueue:%d:" % seq), oid, methodname, args, kwargs)
+        self.putmessage((seq, request))
+        return seq
+
+    def asyncreturn(self, seq):
+        self.debug("asyncreturn:%d:call getresponse(): " % seq)
+        response = self.getresponse(seq, wait=0.05)
+        self.debug(("asyncreturn:%d:response: " % seq), response)
+        return self.decoderesponse(response)
+
+    def decoderesponse(self, response):
+        how, what = response
+        if how == "OK":
+            return what
+        if how == "QUEUED":
+            return None
+        if how == "EXCEPTION":
+            self.debug("decoderesponse: EXCEPTION")
+            return None
+        if how == "EOF":
+            self.debug("decoderesponse: EOF")
+            self.decode_interrupthook()
+            return None
+        if how == "ERROR":
+            self.debug("decoderesponse: Internal ERROR:", what)
+            raise RuntimeError, what
+        raise SystemError, (how, what)
+
+    def decode_interrupthook(self):
+        ""
+        raise EOFError
+
+    def mainloop(self):
+        """Listen on socket until I/O not ready or EOF
+
+        pollresponse() will loop looking for seq number None, which
+        never comes, and exit on EOFError.
+
+        """
+        try:
+            self.getresponse(myseq=None, wait=0.05)
+        except EOFError:
+            self.debug("mainloop:return")
+            return
+
+    def getresponse(self, myseq, wait):
+        response = self._getresponse(myseq, wait)
+        if response is not None:
+            how, what = response
+            if how == "OK":
+                response = how, self._proxify(what)
+        return response
+
+    def _proxify(self, obj):
+        if isinstance(obj, RemoteProxy):
+            return RPCProxy(self, obj.oid)
+        if isinstance(obj, types.ListType):
+            return map(self._proxify, obj)
+        # XXX Check for other types -- not currently needed
+        return obj
+
+    def _getresponse(self, myseq, wait):
+        self.debug("_getresponse:myseq:", myseq)
+        if threading.currentThread() is self.sockthread:
+            # this thread does all reading of requests or responses
+            while 1:
+                response = self.pollresponse(myseq, wait)
+                if response is not None:
+                    return response
+        else:
+            # wait for notification from socket handling thread
+            cvar = self.cvars[myseq]
+            cvar.acquire()
+            while not self.responses.has_key(myseq):
+                cvar.wait()
+            response = self.responses[myseq]
+            self.debug("_getresponse:%s: thread woke up: response: %s" %
+                       (myseq, response))
+            del self.responses[myseq]
+            del self.cvars[myseq]
+            cvar.release()
+            return response
+
+    def newseq(self):
+        self.nextseq = seq = self.nextseq + 2
+        return seq
+
+    def putmessage(self, message):
+        self.debug("putmessage:%d:" % message[0])
+        try:
+            s = pickle.dumps(message)
+        except pickle.PicklingError:
+            print >>sys.__stderr__, "Cannot pickle:", repr(message)
+            raise
+        s = struct.pack("<i", len(s)) + s
+        while len(s) > 0:
+            try:
+                r, w, x = select.select([], [self.sock], [])
+                n = self.sock.send(s[:BUFSIZE])
+            except (AttributeError, TypeError):
+                raise IOError, "socket no longer exists"
+            except socket.error:
+                raise
+            else:
+                s = s[n:]
+
+    buffer = ""
+    bufneed = 4
+    bufstate = 0 # meaning: 0 => reading count; 1 => reading data
+
+    def pollpacket(self, wait):
+        self._stage0()
+        if len(self.buffer) < self.bufneed:
+            r, w, x = select.select([self.sock.fileno()], [], [], wait)
+            if len(r) == 0:
+                return None
+            try:
+                s = self.sock.recv(BUFSIZE)
+            except socket.error:
+                raise EOFError
+            if len(s) == 0:
+                raise EOFError
+            self.buffer += s
+            self._stage0()
+        return self._stage1()
+
+    def _stage0(self):
+        if self.bufstate == 0 and len(self.buffer) >= 4:
+            s = self.buffer[:4]
+            self.buffer = self.buffer[4:]
+            self.bufneed = struct.unpack("<i", s)[0]
+            self.bufstate = 1
+
+    def _stage1(self):
+        if self.bufstate == 1 and len(self.buffer) >= self.bufneed:
+            packet = self.buffer[:self.bufneed]
+            self.buffer = self.buffer[self.bufneed:]
+            self.bufneed = 4
+            self.bufstate = 0
+            return packet
+
+    def pollmessage(self, wait):
+        packet = self.pollpacket(wait)
+        if packet is None:
+            return None
+        try:
+            message = pickle.loads(packet)
+        except pickle.UnpicklingError:
+            print >>sys.__stderr__, "-----------------------"
+            print >>sys.__stderr__, "cannot unpickle packet:", repr(packet)
+            traceback.print_stack(file=sys.__stderr__)
+            print >>sys.__stderr__, "-----------------------"
+            raise
+        return message
+
+    def pollresponse(self, myseq, wait):
+        """Handle messages received on the socket.
+
+        Some messages received may be asynchronous 'call' or 'queue' requests,
+        and some may be responses for other threads.
+
+        'call' requests are passed to self.localcall() with the expectation of
+        immediate execution, during which time the socket is not serviced.
+
+        'queue' requests are used for tasks (which may block or hang) to be
+        processed in a different thread.  These requests are fed into
+        request_queue by self.localcall().  Responses to queued requests are
+        taken from response_queue and sent across the link with the associated
+        sequence numbers.  Messages in the queues are (sequence_number,
+        request/response) tuples and code using this module removing messages
+        from the request_queue is responsible for returning the correct
+        sequence number in the response_queue.
+
+        pollresponse() will loop until a response message with the myseq
+        sequence number is received, and will save other responses in
+        self.responses and notify the owning thread.
+
+        """
+        while 1:
+            # send queued response if there is one available
+            try:
+                qmsg = response_queue.get(0)
+            except Queue.Empty:
+                pass
+            else:
+                seq, response = qmsg
+                message = (seq, ('OK', response))
+                self.putmessage(message)
+            # poll for message on link
+            try:
+                message = self.pollmessage(wait)
+                if message is None:  # socket not ready
+                    return None
+            except EOFError:
+                self.handle_EOF()
+                return None
+            except AttributeError:
+                return None
+            seq, resq = message
+            how = resq[0]
+            self.debug("pollresponse:%d:myseq:%s" % (seq, myseq))
+            # process or queue a request
+            if how in ("CALL", "QUEUE"):
+                self.debug("pollresponse:%d:localcall:call:" % seq)
+                response = self.localcall(seq, resq)
+                self.debug("pollresponse:%d:localcall:response:%s"
+                           % (seq, response))
+                if how == "CALL":
+                    self.putmessage((seq, response))
+                elif how == "QUEUE":
+                    # don't acknowledge the 'queue' request!
+                    pass
+                continue
+            # return if completed message transaction
+            elif seq == myseq:
+                return resq
+            # must be a response for a different thread:
+            else:
+                cv = self.cvars.get(seq, None)
+                # response involving unknown sequence number is discarded,
+                # probably intended for prior incarnation of server
+                if cv is not None:
+                    cv.acquire()
+                    self.responses[seq] = resq
+                    cv.notify()
+                    cv.release()
+                continue
+
+    def handle_EOF(self):
+        "action taken upon link being closed by peer"
+        self.EOFhook()
+        self.debug("handle_EOF")
+        for key in self.cvars:
+            cv = self.cvars[key]
+            cv.acquire()
+            self.responses[key] = ('EOF', None)
+            cv.notify()
+            cv.release()
+        # call our (possibly overridden) exit function
+        self.exithook()
+
+    def EOFhook(self):
+        "Classes using rpc client/server can override to augment EOF action"
+        pass
+
+#----------------- end class SocketIO --------------------
+
+class RemoteObject(object):
+    # Token mix-in class
+    pass
+
+def remoteref(obj):
+    oid = id(obj)
+    objecttable[oid] = obj
+    return RemoteProxy(oid)
+
+class RemoteProxy(object):
+
+    def __init__(self, oid):
+        self.oid = oid
+
+class RPCHandler(SocketServer.BaseRequestHandler, SocketIO):
+
+    debugging = False
+    location = "#S"  # Server
+
+    def __init__(self, sock, addr, svr):
+        svr.current_handler = self ## cgt xxx
+        SocketIO.__init__(self, sock)
+        SocketServer.BaseRequestHandler.__init__(self, sock, addr, svr)
+
+    def handle(self):
+        "handle() method required by SocketServer"
+        self.mainloop()
+
+    def get_remote_proxy(self, oid):
+        return RPCProxy(self, oid)
+
+class RPCClient(SocketIO):
+
+    debugging = False
+    location = "#C"  # Client
+
+    nextseq = 1 # Requests coming from the client are odd numbered
+
+    def __init__(self, address, family=socket.AF_INET, type=socket.SOCK_STREAM):
+        self.listening_sock = socket.socket(family, type)
+        self.listening_sock.setsockopt(socket.SOL_SOCKET,
+                                       socket.SO_REUSEADDR, 1)
+        self.listening_sock.bind(address)
+        self.listening_sock.listen(1)
+
+    def accept(self):
+        working_sock, address = self.listening_sock.accept()
+        if self.debugging:
+            print>>sys.__stderr__, "****** Connection request from ", address
+        if address[0] == LOCALHOST:
+            SocketIO.__init__(self, working_sock)
+        else:
+            print>>sys.__stderr__, "** Invalid host: ", address
+            raise socket.error
+
+    def get_remote_proxy(self, oid):
+        return RPCProxy(self, oid)
+
+class RPCProxy(object):
+
+    __methods = None
+    __attributes = None
+
+    def __init__(self, sockio, oid):
+        self.sockio = sockio
+        self.oid = oid
+
+    def __getattr__(self, name):
+        if self.__methods is None:
+            self.__getmethods()
+        if self.__methods.get(name):
+            return MethodProxy(self.sockio, self.oid, name)
+        if self.__attributes is None:
+            self.__getattributes()
+        if self.__attributes.has_key(name):
+            value = self.sockio.remotecall(self.oid, '__getattribute__',
+                                           (name,), {})
+            return value
+        else:
+            raise AttributeError, name
+
+    def __getattributes(self):
+        self.__attributes = self.sockio.remotecall(self.oid,
+                                                "__attributes__", (), {})
+
+    def __getmethods(self):
+        self.__methods = self.sockio.remotecall(self.oid,
+                                                "__methods__", (), {})
+
+def _getmethods(obj, methods):
+    # Helper to get a list of methods from an object
+    # Adds names to dictionary argument 'methods'
+    for name in dir(obj):
+        attr = getattr(obj, name)
+        if callable(attr):
+            methods[name] = 1
+    if type(obj) == types.InstanceType:
+        _getmethods(obj.__class__, methods)
+    if type(obj) == types.ClassType:
+        for super in obj.__bases__:
+            _getmethods(super, methods)
+
+def _getattributes(obj, attributes):
+    for name in dir(obj):
+        attr = getattr(obj, name)
+        if not callable(attr):
+            attributes[name] = 1
+
+class MethodProxy(object):
+
+    def __init__(self, sockio, oid, name):
+        self.sockio = sockio
+        self.oid = oid
+        self.name = name
+
+    def __call__(self, *args, **kwargs):
+        value = self.sockio.remotecall(self.oid, self.name, args, kwargs)
+        return value
+
+
+# XXX KBK 09Sep03  We need a proper unit test for this module.  Previously
+#                  existing test code was removed at Rev 1.27.