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diff --git a/WebKitTools/pywebsocket/mod_pywebsocket/msgutil.py b/WebKitTools/pywebsocket/mod_pywebsocket/msgutil.py
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+++ b/WebKitTools/pywebsocket/mod_pywebsocket/msgutil.py
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+# Copyright 2009, Google Inc.
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#     * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above
+# copyright notice, this list of conditions and the following disclaimer
+# in the documentation and/or other materials provided with the
+# distribution.
+#     * Neither the name of Google Inc. nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+
+"""Message related utilities.
+
+Note: request.connection.write/read are used in this module, even though
+mod_python document says that they should be used only in connection handlers.
+Unfortunately, we have no other options. For example, request.write/read are
+not suitable because they don't allow direct raw bytes writing/reading.
+"""
+
+
+import Queue
+import threading
+
+
+def send_message(request, message):
+    """Send message.
+
+    Args:
+        request: mod_python request.
+        message: unicode string to send.
+    """
+
+    request.connection.write('\x00' + message.encode('utf-8') + '\xff')
+
+
+def receive_message(request):
+    """Receive a Web Socket frame and return its payload as unicode string.
+
+    Args:
+        request: mod_python request.
+    """
+
+    while True:
+        # Read 1 byte.
+        # mp_conn.read will block if no bytes are available.
+        # Timeout is controlled by TimeOut directive of Apache.
+        frame_type_str = request.connection.read(1)
+        frame_type = ord(frame_type_str[0])
+        if (frame_type & 0x80) == 0x80:
+            # The payload length is specified in the frame.
+            # Read and discard.
+            length = _payload_length(request)
+            _receive_bytes(request, length)
+        else:
+            # The payload is delimited with \xff.
+            bytes = _read_until(request, '\xff')
+            message = bytes.decode('utf-8')
+            if frame_type == 0x00:
+                return message
+            # Discard data of other types.
+
+
+def _payload_length(request):
+    length = 0
+    while True:
+        b_str = request.connection.read(1)
+        b = ord(b_str[0])
+        length = length * 128 + (b & 0x7f)
+        if (b & 0x80) == 0:
+            break
+    return length
+
+
+def _receive_bytes(request, length):
+    bytes = []
+    while length > 0:
+        new_bytes = request.connection.read(length)
+        bytes.append(new_bytes)
+        length -= len(new_bytes)
+    return ''.join(bytes)
+
+
+def _read_until(request, delim_char):
+    bytes = []
+    while True:
+        ch = request.connection.read(1)
+        if ch == delim_char:
+            break
+        bytes.append(ch)
+    return ''.join(bytes)
+
+
+class MessageReceiver(threading.Thread):
+    """This class receives messages from the client.
+
+    This class provides three ways to receive messages: blocking, non-blocking,
+    and via callback. Callback has the highest precedence.
+
+    Note: This class should not be used with the standalone server for wss
+    because pyOpenSSL used by the server raises a fatal error if the socket
+    is accessed from multiple threads.
+    """
+    def __init__(self, request, onmessage=None):
+        """Construct an instance.
+
+        Args:
+            request: mod_python request.
+            onmessage: a function to be called when a message is received.
+                       May be None. If not None, the function is called on
+                       another thread. In that case, MessageReceiver.receive
+                       and MessageReceiver.receive_nowait are useless because
+                       they will never return any messages.
+        """
+        threading.Thread.__init__(self)
+        self._request = request
+        self._queue = Queue.Queue()
+        self._onmessage = onmessage
+        self._stop_requested = False
+        self.setDaemon(True)
+        self.start()
+
+    def run(self):
+        while not self._stop_requested:
+            message = receive_message(self._request)
+            if self._onmessage:
+                self._onmessage(message)
+            else:
+                self._queue.put(message)
+
+    def receive(self):
+        """ Receive a message from the channel, blocking.
+
+        Returns:
+            message as a unicode string.
+        """
+        return self._queue.get()
+
+    def receive_nowait(self):
+        """ Receive a message from the channel, non-blocking.
+
+        Returns:
+            message as a unicode string if available. None otherwise.
+        """
+        try:
+            message = self._queue.get_nowait()
+        except Queue.Empty:
+            message = None
+        return message
+
+    def stop(self):
+        """Request to stop this instance.
+
+        The instance will be stopped after receiving the next message.
+        This method may not be very useful, but there is no clean way
+        in Python to forcefully stop a running thread.
+        """
+        self._stop_requested = True
+
+
+class MessageSender(threading.Thread):
+    """This class sends messages to the client.
+
+    This class provides both synchronous and asynchronous ways to send
+    messages.
+
+    Note: This class should not be used with the standalone server for wss
+    because pyOpenSSL used by the server raises a fatal error if the socket
+    is accessed from multiple threads.
+    """
+    def __init__(self, request):
+        """Construct an instance.
+
+        Args:
+            request: mod_python request.
+        """
+        threading.Thread.__init__(self)
+        self._request = request
+        self._queue = Queue.Queue()
+        self.setDaemon(True)
+        self.start()
+
+    def run(self):
+        while True:
+            message, condition = self._queue.get()
+            condition.acquire()
+            send_message(self._request, message)
+            condition.notify()
+            condition.release()
+
+    def send(self, message):
+        """Send a message, blocking."""
+
+        condition = threading.Condition()
+        condition.acquire()
+        self._queue.put((message, condition))
+        condition.wait()
+
+    def send_nowait(self, message):
+        """Send a message, non-blocking."""
+
+        self._queue.put((message, threading.Condition()))
+
+
+# vi:sts=4 sw=4 et