--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/python-2.5.2/win32/Lib/asynchat.py Fri Apr 03 17:19:34 2009 +0100
@@ -0,0 +1,295 @@
+# -*- Mode: Python; tab-width: 4 -*-
+# Id: asynchat.py,v 2.26 2000/09/07 22:29:26 rushing Exp
+# Author: Sam Rushing <rushing@nightmare.com>
+
+# ======================================================================
+# Copyright 1996 by Sam Rushing
+#
+# All Rights Reserved
+#
+# Permission to use, copy, modify, and distribute this software and
+# its documentation for any purpose and without fee is hereby
+# granted, provided that the above copyright notice appear in all
+# copies and that both that copyright notice and this permission
+# notice appear in supporting documentation, and that the name of Sam
+# Rushing not be used in advertising or publicity pertaining to
+# distribution of the software without specific, written prior
+# permission.
+#
+# SAM RUSHING DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+# INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN
+# NO EVENT SHALL SAM RUSHING BE LIABLE FOR ANY SPECIAL, INDIRECT OR
+# CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
+# OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
+# NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+# CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+# ======================================================================
+
+r"""A class supporting chat-style (command/response) protocols.
+
+This class adds support for 'chat' style protocols - where one side
+sends a 'command', and the other sends a response (examples would be
+the common internet protocols - smtp, nntp, ftp, etc..).
+
+The handle_read() method looks at the input stream for the current
+'terminator' (usually '\r\n' for single-line responses, '\r\n.\r\n'
+for multi-line output), calling self.found_terminator() on its
+receipt.
+
+for example:
+Say you build an async nntp client using this class. At the start
+of the connection, you'll have self.terminator set to '\r\n', in
+order to process the single-line greeting. Just before issuing a
+'LIST' command you'll set it to '\r\n.\r\n'. The output of the LIST
+command will be accumulated (using your own 'collect_incoming_data'
+method) up to the terminator, and then control will be returned to
+you - by calling your self.found_terminator() method.
+"""
+
+import socket
+import asyncore
+from collections import deque
+
+class async_chat (asyncore.dispatcher):
+ """This is an abstract class. You must derive from this class, and add
+ the two methods collect_incoming_data() and found_terminator()"""
+
+ # these are overridable defaults
+
+ ac_in_buffer_size = 4096
+ ac_out_buffer_size = 4096
+
+ def __init__ (self, conn=None):
+ self.ac_in_buffer = ''
+ self.ac_out_buffer = ''
+ self.producer_fifo = fifo()
+ asyncore.dispatcher.__init__ (self, conn)
+
+ def collect_incoming_data(self, data):
+ raise NotImplementedError, "must be implemented in subclass"
+
+ def found_terminator(self):
+ raise NotImplementedError, "must be implemented in subclass"
+
+ def set_terminator (self, term):
+ "Set the input delimiter. Can be a fixed string of any length, an integer, or None"
+ self.terminator = term
+
+ def get_terminator (self):
+ return self.terminator
+
+ # grab some more data from the socket,
+ # throw it to the collector method,
+ # check for the terminator,
+ # if found, transition to the next state.
+
+ def handle_read (self):
+
+ try:
+ data = self.recv (self.ac_in_buffer_size)
+ except socket.error, why:
+ self.handle_error()
+ return
+
+ self.ac_in_buffer = self.ac_in_buffer + data
+
+ # Continue to search for self.terminator in self.ac_in_buffer,
+ # while calling self.collect_incoming_data. The while loop
+ # is necessary because we might read several data+terminator
+ # combos with a single recv(1024).
+
+ while self.ac_in_buffer:
+ lb = len(self.ac_in_buffer)
+ terminator = self.get_terminator()
+ if not terminator:
+ # no terminator, collect it all
+ self.collect_incoming_data (self.ac_in_buffer)
+ self.ac_in_buffer = ''
+ elif isinstance(terminator, int) or isinstance(terminator, long):
+ # numeric terminator
+ n = terminator
+ if lb < n:
+ self.collect_incoming_data (self.ac_in_buffer)
+ self.ac_in_buffer = ''
+ self.terminator = self.terminator - lb
+ else:
+ self.collect_incoming_data (self.ac_in_buffer[:n])
+ self.ac_in_buffer = self.ac_in_buffer[n:]
+ self.terminator = 0
+ self.found_terminator()
+ else:
+ # 3 cases:
+ # 1) end of buffer matches terminator exactly:
+ # collect data, transition
+ # 2) end of buffer matches some prefix:
+ # collect data to the prefix
+ # 3) end of buffer does not match any prefix:
+ # collect data
+ terminator_len = len(terminator)
+ index = self.ac_in_buffer.find(terminator)
+ if index != -1:
+ # we found the terminator
+ if index > 0:
+ # don't bother reporting the empty string (source of subtle bugs)
+ self.collect_incoming_data (self.ac_in_buffer[:index])
+ self.ac_in_buffer = self.ac_in_buffer[index+terminator_len:]
+ # This does the Right Thing if the terminator is changed here.
+ self.found_terminator()
+ else:
+ # check for a prefix of the terminator
+ index = find_prefix_at_end (self.ac_in_buffer, terminator)
+ if index:
+ if index != lb:
+ # we found a prefix, collect up to the prefix
+ self.collect_incoming_data (self.ac_in_buffer[:-index])
+ self.ac_in_buffer = self.ac_in_buffer[-index:]
+ break
+ else:
+ # no prefix, collect it all
+ self.collect_incoming_data (self.ac_in_buffer)
+ self.ac_in_buffer = ''
+
+ def handle_write (self):
+ self.initiate_send ()
+
+ def handle_close (self):
+ self.close()
+
+ def push (self, data):
+ self.producer_fifo.push (simple_producer (data))
+ self.initiate_send()
+
+ def push_with_producer (self, producer):
+ self.producer_fifo.push (producer)
+ self.initiate_send()
+
+ def readable (self):
+ "predicate for inclusion in the readable for select()"
+ return (len(self.ac_in_buffer) <= self.ac_in_buffer_size)
+
+ def writable (self):
+ "predicate for inclusion in the writable for select()"
+ # return len(self.ac_out_buffer) or len(self.producer_fifo) or (not self.connected)
+ # this is about twice as fast, though not as clear.
+ return not (
+ (self.ac_out_buffer == '') and
+ self.producer_fifo.is_empty() and
+ self.connected
+ )
+
+ def close_when_done (self):
+ "automatically close this channel once the outgoing queue is empty"
+ self.producer_fifo.push (None)
+
+ # refill the outgoing buffer by calling the more() method
+ # of the first producer in the queue
+ def refill_buffer (self):
+ while 1:
+ if len(self.producer_fifo):
+ p = self.producer_fifo.first()
+ # a 'None' in the producer fifo is a sentinel,
+ # telling us to close the channel.
+ if p is None:
+ if not self.ac_out_buffer:
+ self.producer_fifo.pop()
+ self.close()
+ return
+ elif isinstance(p, str):
+ self.producer_fifo.pop()
+ self.ac_out_buffer = self.ac_out_buffer + p
+ return
+ data = p.more()
+ if data:
+ self.ac_out_buffer = self.ac_out_buffer + data
+ return
+ else:
+ self.producer_fifo.pop()
+ else:
+ return
+
+ def initiate_send (self):
+ obs = self.ac_out_buffer_size
+ # try to refill the buffer
+ if (len (self.ac_out_buffer) < obs):
+ self.refill_buffer()
+
+ if self.ac_out_buffer and self.connected:
+ # try to send the buffer
+ try:
+ num_sent = self.send (self.ac_out_buffer[:obs])
+ if num_sent:
+ self.ac_out_buffer = self.ac_out_buffer[num_sent:]
+
+ except socket.error, why:
+ self.handle_error()
+ return
+
+ def discard_buffers (self):
+ # Emergencies only!
+ self.ac_in_buffer = ''
+ self.ac_out_buffer = ''
+ while self.producer_fifo:
+ self.producer_fifo.pop()
+
+
+class simple_producer:
+
+ def __init__ (self, data, buffer_size=512):
+ self.data = data
+ self.buffer_size = buffer_size
+
+ def more (self):
+ if len (self.data) > self.buffer_size:
+ result = self.data[:self.buffer_size]
+ self.data = self.data[self.buffer_size:]
+ return result
+ else:
+ result = self.data
+ self.data = ''
+ return result
+
+class fifo:
+ def __init__ (self, list=None):
+ if not list:
+ self.list = deque()
+ else:
+ self.list = deque(list)
+
+ def __len__ (self):
+ return len(self.list)
+
+ def is_empty (self):
+ return not self.list
+
+ def first (self):
+ return self.list[0]
+
+ def push (self, data):
+ self.list.append(data)
+
+ def pop (self):
+ if self.list:
+ return (1, self.list.popleft())
+ else:
+ return (0, None)
+
+# Given 'haystack', see if any prefix of 'needle' is at its end. This
+# assumes an exact match has already been checked. Return the number of
+# characters matched.
+# for example:
+# f_p_a_e ("qwerty\r", "\r\n") => 1
+# f_p_a_e ("qwertydkjf", "\r\n") => 0
+# f_p_a_e ("qwerty\r\n", "\r\n") => <undefined>
+
+# this could maybe be made faster with a computed regex?
+# [answer: no; circa Python-2.0, Jan 2001]
+# new python: 28961/s
+# old python: 18307/s
+# re: 12820/s
+# regex: 14035/s
+
+def find_prefix_at_end (haystack, needle):
+ l = len(needle) - 1
+ while l and not haystack.endswith(needle[:l]):
+ l -= 1
+ return l