2014-01-13 15:39:04 -05:00

110 lines
3.4 KiB
Python

#
# Licensed to the Apache Software Foundation (ASF) under one
# or more contributor license agreements. See the NOTICE file
# distributed with this work for additional information
# regarding copyright ownership. The ASF licenses this file
# to you under the Apache License, Version 2.0 (the
# "License"); you may not use this file except in compliance
# with the License. You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing,
# software distributed under the License is distributed on an
# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
# KIND, either express or implied. See the License for the
# specific language governing permissions and limitations
# under the License.
#
__all__ = [
"read_socket_input",
"write_socket_output"
]
import socket, errno, logging
from connection import Connection
LOG = logging.getLogger(__name__)
"""helper methods that provide boilerplate socket I/O and Connection
processing.
"""
def read_socket_input(connection, socket_obj):
"""Read from the network layer and processes all data read. Can
support both blocking and non-blocking sockets.
Returns the number of input bytes processed, or EOS if input processing
is done. Any exceptions raised by the socket are re-raised.
"""
count = connection.needs_input
if count <= 0:
return count # 0 or EOS
try:
sock_data = socket_obj.recv(count)
except socket.timeout, e:
LOG.debug("Socket timeout exception %s", str(e))
raise # caller must handle
except socket.error, e:
LOG.debug("Socket error exception %s", str(e))
err = e.args[0]
# ignore non-fatal errors
if (err != errno.EAGAIN and
err != errno.EWOULDBLOCK and
err != errno.EINTR):
# otherwise, unrecoverable:
connection.close_input()
raise # caller must handle
except Exception, e: # beats me... assume fatal
LOG.debug("unknown socket exception %s", str(e))
connection.close_input()
raise # caller must handle
if sock_data:
count = connection.process_input( sock_data )
else:
LOG.debug("Socket closed")
count = Connection.EOS
connection.close_input()
return count
def write_socket_output(connection, socket_obj):
"""Write data to the network layer. Can support both blocking and
non-blocking sockets.
"""
count = connection.has_output
if count <= 0:
return count # 0 or EOS
data = connection.output_data()
try:
count = socket_obj.send(data)
except socket.timeout, e:
LOG.debug("Socket timeout exception %s", str(e))
raise # caller must handle
except socket.error, e:
LOG.debug("Socket error exception %s", str(e))
err = e.args[0]
# ignore non-fatal errors
if (err != errno.EAGAIN and
err != errno.EWOULDBLOCK and
err != errno.EINTR):
# otherwise, unrecoverable
connection.close_output()
raise
except Exception, e: # beats me... assume fatal
LOG.debug("unknown socket exception %s", str(e))
connection.close_output()
raise
if count > 0:
connection.output_written(count)
elif data:
LOG.debug("Socket closed")
count = Connection.EOS
connection.close_output()
return count