A gift from Sam Rushing - modules asyncore and asynchat for the
standard Python library. (Async socket support.)
diff --git a/Lib/asynchat.py b/Lib/asynchat.py
new file mode 100644
index 0000000..5486419
--- /dev/null
+++ b/Lib/asynchat.py
@@ -0,0 +1,290 @@
+# -*- Mode: Python; tab-width: 4 -*-
+# $Id$
+# 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.
+# ======================================================================
+
+import socket
+import asyncore
+import string
+
+# 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
+
+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 set_terminator (self, term):
+ "Set the input delimiter. Can be a fixed string of any length, or None"
+ if term is None:
+ self.terminator = ''
+ else:
+ 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:
+ import sys
+ self.handle_error (sys.exc_type, sys.exc_value, sys.exc_traceback)
+ 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:
+ terminator = self.get_terminator()
+ terminator_len = len(terminator)
+ # 4 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
+ # 4) no terminator, just collect the data
+ if terminator:
+ index = string.find (self.ac_in_buffer, terminator)
+ if index != -1:
+ # we found the terminator
+ 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:
+ # 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 = ''
+ else:
+ # no terminator, 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):
+ return (len(self.ac_in_buffer) <= self.ac_in_buffer_size)
+
+ def writable (self):
+ return len(self.ac_out_buffer) or len(self.producer_fifo) or (not self.connected)
+
+ def close_when_done (self):
+ 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
+ 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 (not self._push_mode) and (len (self.ac_out_buffer) < obs):
+ self.refill_buffer()
+
+ if self.ac_out_buffer and self.connected:
+ # try to send the buffer
+ num_sent = self.send (self.ac_out_buffer[:obs])
+ if num_sent:
+ self.ac_out_buffer = self.ac_out_buffer[num_sent:]
+
+ def discard_buffers (self):
+ # Emergencies only!
+ self.ac_in_buffer = ''
+ self.ac_out_buffer == ''
+ while self.producer_fifo:
+ self.producer_fifo.pop()
+
+ # ==================================================
+ # support for push mode.
+ # ==================================================
+ _push_mode = 0
+ def push_mode (self, boolean):
+ self._push_mode = boolean
+
+ def writable_push (self):
+ return self.connected and len(self.ac_out_buffer)
+
+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 = []
+ else:
+ self.list = list
+
+ def __len__ (self):
+ return len(self.list)
+
+ def first (self):
+ return self.list[0]
+
+ def push (self, data):
+ self.list.append (data)
+
+ def pop (self):
+ if self.list:
+ result = self.list[0]
+ del self.list[0]
+ return (1, result)
+ 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 ("qwerty\r\n", "\r\n") => 2
+# f_p_a_e ("qwertydkjf", "\r\n") => 0
+
+# this could maybe be made faster with a computed regex?
+
+##def find_prefix_at_end (haystack, needle):
+## nl = len(needle)
+## result = 0
+## for i in range (1,nl):
+## if haystack[-(nl-i):] == needle[:(nl-i)]:
+## result = nl-i
+## break
+## return result
+
+# yes, this is about twice as fast, but still seems
+# to be neglible CPU. The previous could do about 290
+# searches/sec. the new one about 555/sec.
+
+import regex
+
+prefix_cache = {}
+
+def prefix_regex (needle):
+ if prefix_cache.has_key (needle):
+ return prefix_cache[needle]
+ else:
+ reg = needle[-1]
+ for i in range(1,len(needle)):
+ reg = '%c\(%s\)?' % (needle[-(i+1)], reg)
+ reg = regex.compile (reg+'$')
+ prefix_cache[needle] = reg, len(needle)
+ return reg, len(needle)
+
+def find_prefix_at_end (haystack, needle):
+ reg, length = prefix_regex (needle)
+ lh = len(haystack)
+ result = reg.search (haystack, max(0,lh-length))
+ if result >= 0:
+ return (lh - result)
+ else:
+ return 0
diff --git a/Lib/asyncore.py b/Lib/asyncore.py
new file mode 100644
index 0000000..c9b39a3
--- /dev/null
+++ b/Lib/asyncore.py
@@ -0,0 +1,453 @@
+# -*- Mode: Python; tab-width: 4 -*-
+# $Id$
+# 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.
+# ======================================================================
+
+import select
+import socket
+import string
+import sys
+
+import os
+if os.name == 'nt':
+ EWOULDBLOCK = 10035
+ EINPROGRESS = 10036
+ EALREADY = 10037
+ ECONNRESET = 10054
+ ENOTCONN = 10057
+else:
+ from errno import EALREADY, EINPROGRESS, EWOULDBLOCK, ECONNRESET, ENOTCONN
+
+socket_map = {}
+
+def poll (timeout=0.0, ignore_expt=1):
+ if socket_map:
+ sockets = socket_map.keys()
+ r = filter (lambda x: x.readable(), sockets)
+ w = filter (lambda x: x.writable(), sockets)
+ if ignore_expt:
+ e = []
+ else:
+ e = sockets[:]
+
+ (r,w,e) = select.select (r,w,e, timeout)
+
+ for x in e:
+ try:
+ x.handle_expt_event()
+ except:
+ x.handle_error (sys.exc_type, sys.exc_value, sys.exc_traceback)
+ for x in r:
+ try:
+ x.handle_read_event()
+ except:
+ x.handle_error (sys.exc_type, sys.exc_value, sys.exc_traceback)
+ for x in w:
+ try:
+ x.handle_write_event()
+ except:
+ x.handle_error (sys.exc_type, sys.exc_value, sys.exc_traceback)
+
+def poll2 (timeout=0.0):
+ import poll
+ # timeout is in milliseconds
+ timeout = int(timeout*1000)
+ if socket_map:
+ fd_map = {}
+ for s in socket_map.keys():
+ fd_map[s.fileno()] = s
+ l = []
+ for fd, s in fd_map.items():
+ flags = 0
+ if s.readable():
+ flags = poll.POLLIN
+ if s.writable():
+ flags = flags | poll.POLLOUT
+ if flags:
+ l.append (fd, flags)
+ r = poll.poll (l, timeout)
+ print r
+ for fd, flags in r:
+ s = fd_map[fd]
+ try:
+ if (flags & poll.POLLIN):
+ s.handle_read_event()
+ if (flags & poll.POLLOUT):
+ s.handle_write_event()
+ if (flags & poll.POLLERR):
+ s.handle_expt_event()
+ except:
+ apply (s.handle_error, sys.exc_info())
+
+
+def loop (timeout=30.0, use_poll=0):
+
+ if use_poll:
+ poll_fun = poll2
+ else:
+ poll_fun = poll
+
+ while socket_map:
+ poll_fun (timeout)
+
+class dispatcher:
+ debug = 0
+ connected = 0
+ accepting = 0
+ closing = 0
+ addr = None
+
+ def __init__ (self, sock=None):
+ if sock:
+ self.set_socket (sock)
+ # I think it should inherit this anyway
+ self.socket.setblocking (0)
+ self.connected = 1
+
+ def __repr__ (self):
+ try:
+ status = []
+ if self.accepting and self.addr:
+ status.append ('listening')
+ elif self.connected:
+ status.append ('connected')
+ if self.addr:
+ status.append ('%s:%d' % self.addr)
+ return '<%s %s at %x>' % (
+ self.__class__.__name__,
+ string.join (status, ' '),
+ id(self)
+ )
+ except:
+ try:
+ ar = repr(self.addr)
+ except:
+ ar = 'no self.addr!'
+
+ return '<__repr__ (self) failed for object at %x (addr=%s)>' % (id(self),ar)
+
+ def add_channel (self):
+ self.log ('adding channel %s' % self)
+ socket_map [self] = 1
+
+ def del_channel (self):
+ if socket_map.has_key (self):
+ self.log ('closing channel %d:%s' % (self.fileno(), self))
+ del socket_map [self]
+
+ def create_socket (self, family, type):
+ self.family_and_type = family, type
+ self.socket = socket.socket (family, type)
+ self.socket.setblocking(0)
+ self.add_channel()
+
+ def set_socket (self, socket):
+ self.socket = socket
+ self.add_channel()
+
+ def set_reuse_addr (self):
+ # try to re-use a server port if possible
+ try:
+ self.socket.setsockopt (
+ socket.SOL_SOCKET, socket.SO_REUSEADDR,
+ self.socket.getsockopt (socket.SOL_SOCKET, socket.SO_REUSEADDR) | 1
+ )
+ except:
+ pass
+
+ # ==================================================
+ # predicates for select()
+ # these are used as filters for the lists of sockets
+ # to pass to select().
+ # ==================================================
+
+ def readable (self):
+ return 1
+
+ if os.name == 'mac':
+ # The macintosh will select a listening socket for
+ # write if you let it. What might this mean?
+ def writable (self):
+ return not self.accepting
+ else:
+ def writable (self):
+ return 1
+
+ # ==================================================
+ # socket object methods.
+ # ==================================================
+
+ def listen (self, num):
+ self.accepting = 1
+ if os.name == 'nt' and num > 5:
+ num = 1
+ return self.socket.listen (num)
+
+ def bind (self, addr):
+ self.addr = addr
+ return self.socket.bind (addr)
+
+ def connect (self, address):
+ try:
+ self.socket.connect (address)
+ except socket.error, why:
+ if why[0] in (EINPROGRESS, EALREADY, EWOULDBLOCK):
+ return
+ else:
+ raise socket.error, why
+ self.connected = 1
+ self.handle_connect()
+
+ def accept (self):
+ try:
+ conn, addr = self.socket.accept()
+ return conn, addr
+ except socket.error, why:
+ if why[0] == EWOULDBLOCK:
+ pass
+ else:
+ raise socket.error, why
+
+ def send (self, data):
+ try:
+ result = self.socket.send (data)
+ return result
+ except socket.error, why:
+ if why[0] == EWOULDBLOCK:
+ return 0
+ else:
+ raise socket.error, why
+ return 0
+
+ def recv (self, buffer_size):
+ try:
+ data = self.socket.recv (buffer_size)
+ if not data:
+ # a closed connection is indicated by signaling
+ # a read condition, and having recv() return 0.
+ self.handle_close()
+ return ''
+ else:
+ return data
+ except socket.error, why:
+ # winsock sometimes throws ENOTCONN
+ if why[0] in [ECONNRESET, ENOTCONN]:
+ self.handle_close()
+ return ''
+ else:
+ raise socket.error, why
+
+ def close (self):
+ self.del_channel()
+ self.socket.close()
+ self.connected = 0
+
+ # cheap inheritance, used to pass all other attribute
+ # references to the underlying socket object.
+ def __getattr__ (self, attr):
+ if attr != 'socket':
+ return getattr (self.socket, attr)
+ else:
+ raise AttributeError, attr
+
+ def log (self, message):
+ print 'log:', message
+
+ def handle_read_event (self):
+ if self.accepting:
+ # for an accepting socket, getting a read implies
+ # that we are connected
+ if not self.connected:
+ self.connected = 1
+ self.handle_accept()
+ elif not self.connected:
+ self.handle_connect()
+ self.connected = 1
+ self.handle_read()
+ else:
+ self.handle_read()
+
+ def handle_write_event (self):
+ # getting a write implies that we are connected
+ if not self.connected:
+ self.handle_connect()
+ self.connected = 1
+ self.handle_write()
+
+ def handle_expt_event (self):
+ self.handle_expt()
+
+ def handle_error (self, *info):
+ (t,v,tb) = info
+ (file,fun,line), tbinfo = compact_traceback (t,v,tb)
+
+ # sometimes a user repr method will crash.
+ try:
+ self_repr = repr (self)
+ except:
+ self_repr = '<__repr__ (self) failed for object at %0x>' % id(self)
+
+ print (
+ 'uncaptured python exception, closing channel %s (%s:%s %s)' % (
+ self_repr,
+ str(t),
+ str(v),
+ tbinfo
+ )
+ )
+ del t,v,tb
+ self.close()
+
+ def handle_expt (self):
+ self.log ('unhandled exception')
+
+ def handle_read (self):
+ self.log ('unhandled read event')
+
+ def handle_write (self):
+ self.log ('unhandled write event')
+
+ def handle_connect (self):
+ self.log ('unhandled connect event')
+
+ def handle_oob (self):
+ self.log ('unhandled out-of-band event')
+
+ def handle_accept (self):
+ self.log ('unhandled accept event')
+
+ def handle_close (self):
+ self.log ('unhandled close event')
+ self.close()
+
+# ---------------------------------------------------------------------------
+# adds simple buffered output capability, useful for simple clients.
+# [for more sophisticated usage use asynchat.async_chat]
+# ---------------------------------------------------------------------------
+
+class dispatcher_with_send (dispatcher):
+ def __init__ (self, sock=None):
+ dispatcher.__init__ (self, sock)
+ self.out_buffer = ''
+
+ def initiate_send (self):
+ num_sent = 0
+ num_sent = dispatcher.send (self, self.out_buffer[:512])
+ self.out_buffer = self.out_buffer[num_sent:]
+
+ def handle_write (self):
+ self.initiate_send()
+
+ def writable (self):
+ return (not self.connected) or len(self.out_buffer)
+
+ def send (self, data):
+ if self.debug:
+ self.log ('sending %s' % repr(data))
+ self.out_buffer = self.out_buffer + data
+ self.initiate_send()
+
+# ---------------------------------------------------------------------------
+# used for debugging.
+# ---------------------------------------------------------------------------
+
+def compact_traceback (t,v,tb):
+ tbinfo = []
+ while 1:
+ tbinfo.append (
+ tb.tb_frame.f_code.co_filename,
+ tb.tb_frame.f_code.co_name,
+ str(tb.tb_lineno)
+ )
+ tb = tb.tb_next
+ if not tb:
+ break
+
+ file, function, line = tbinfo[-1]
+ info = '[' + string.join (
+ map (
+ lambda x: string.join (x, '|'),
+ tbinfo
+ ),
+ '] ['
+ ) + ']'
+ return (file, function, line), info
+
+def close_all ():
+ global socket_map
+ for x in socket_map.keys():
+ x.socket.close()
+ socket_map.clear()
+
+# Asynchronous File I/O:
+#
+# After a little research (reading man pages on various unixen, and
+# digging through the linux kernel), I've determined that select()
+# isn't meant for doing doing asynchronous file i/o.
+# Heartening, though - reading linux/mm/filemap.c shows that linux
+# supports asynchronous read-ahead. So _MOST_ of the time, the data
+# will be sitting in memory for us already when we go to read it.
+#
+# What other OS's (besides NT) support async file i/o? [VMS?]
+#
+# Regardless, this is useful for pipes, and stdin/stdout...
+
+import os
+if os.name == 'posix':
+ import fcntl
+ import FCNTL
+
+ class file_wrapper:
+ # here we override just enough to make a file
+ # look like a socket for the purposes of asyncore.
+ def __init__ (self, fd):
+ self.fd = fd
+
+ def recv (self, *args):
+ return apply (os.read, (self.fd,)+args)
+
+ def write (self, *args):
+ return apply (os.write, (self.fd,)+args)
+
+ def close (self):
+ return os.close (self.fd)
+
+ def fileno (self):
+ return self.fd
+
+ class file_dispatcher (dispatcher):
+ def __init__ (self, fd):
+ dispatcher.__init__ (self)
+ self.connected = 1
+ # set it to non-blocking mode
+ flags = fcntl.fcntl (fd, FCNTL.F_GETFL, 0)
+ flags = flags | FCNTL.O_NONBLOCK
+ fcntl.fcntl (fd, FCNTL.F_SETFL, flags)
+ self.set_file (fd)
+
+ def set_file (self, fd):
+ self.socket = file_wrapper (fd)
+ self.add_channel()
+#not really