add hg and python

sys/lib/python/asyncore.py

@@ -0,0 +1,551 @@
+# -*- Mode: Python -*-
+#   Id: asyncore.py,v 2.51 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.
+# ======================================================================
+
+"""Basic infrastructure for asynchronous socket service clients and servers.
+
+There are only two ways to have a program on a single processor do "more
+than one thing at a time".  Multi-threaded programming is the simplest and
+most popular way to do it, but there is another very different technique,
+that lets you have nearly all the advantages of multi-threading, without
+actually using multiple threads. it's really only practical if your program
+is largely I/O bound. If your program is CPU bound, then pre-emptive
+scheduled threads are probably what you really need. Network servers are
+rarely CPU-bound, however.
+
+If your operating system supports the select() system call in its I/O
+library (and nearly all do), then you can use it to juggle multiple
+communication channels at once; doing other work while your I/O is taking
+place in the "background."  Although this strategy can seem strange and
+complex, especially at first, it is in many ways easier to understand and
+control than multi-threaded programming. The module documented here solves
+many of the difficult problems for you, making the task of building
+sophisticated high-performance network servers and clients a snap.
+"""
+
+import select
+import socket
+import sys
+import time
+
+import os
+from errno import EALREADY, EINPROGRESS, EWOULDBLOCK, ECONNRESET, \
+     ENOTCONN, ESHUTDOWN, EINTR, EISCONN, errorcode
+
+try:
+    socket_map
+except NameError:
+    socket_map = {}
+
+class ExitNow(Exception):
+    pass
+
+def read(obj):
+    try:
+        obj.handle_read_event()
+    except ExitNow:
+        raise
+    except:
+        obj.handle_error()
+
+def write(obj):
+    try:
+        obj.handle_write_event()
+    except ExitNow:
+        raise
+    except:
+        obj.handle_error()
+
+def _exception (obj):
+    try:
+        obj.handle_expt_event()
+    except ExitNow:
+        raise
+    except:
+        obj.handle_error()
+
+def readwrite(obj, flags):
+    try:
+        if flags & (select.POLLIN | select.POLLPRI):
+            obj.handle_read_event()
+        if flags & select.POLLOUT:
+            obj.handle_write_event()
+        if flags & (select.POLLERR | select.POLLHUP | select.POLLNVAL):
+            obj.handle_expt_event()
+    except ExitNow:
+        raise
+    except:
+        obj.handle_error()
+
+def poll(timeout=0.0, map=None):
+    if map is None:
+        map = socket_map
+    if map:
+        r = []; w = []; e = []
+        for fd, obj in map.items():
+            is_r = obj.readable()
+            is_w = obj.writable()
+            if is_r:
+                r.append(fd)
+            if is_w:
+                w.append(fd)
+            if is_r or is_w:
+                e.append(fd)
+        if [] == r == w == e:
+            time.sleep(timeout)
+        else:
+            try:
+                r, w, e = select.select(r, w, e, timeout)
+            except select.error, err:
+                if err[0] != EINTR:
+                    raise
+                else:
+                    return
+
+        for fd in r:
+            obj = map.get(fd)
+            if obj is None:
+                continue
+            read(obj)
+
+        for fd in w:
+            obj = map.get(fd)
+            if obj is None:
+                continue
+            write(obj)
+
+        for fd in e:
+            obj = map.get(fd)
+            if obj is None:
+                continue
+            _exception(obj)
+
+def poll2(timeout=0.0, map=None):
+    # Use the poll() support added to the select module in Python 2.0
+    if map is None:
+        map = socket_map
+    if timeout is not None:
+        # timeout is in milliseconds
+        timeout = int(timeout*1000)
+    pollster = select.poll()
+    if map:
+        for fd, obj in map.items():
+            flags = 0
+            if obj.readable():
+                flags |= select.POLLIN | select.POLLPRI
+            if obj.writable():
+                flags |= select.POLLOUT
+            if flags:
+                # Only check for exceptions if object was either readable
+                # or writable.
+                flags |= select.POLLERR | select.POLLHUP | select.POLLNVAL
+                pollster.register(fd, flags)
+        try:
+            r = pollster.poll(timeout)
+        except select.error, err:
+            if err[0] != EINTR:
+                raise
+            r = []
+        for fd, flags in r:
+            obj = map.get(fd)
+            if obj is None:
+                continue
+            readwrite(obj, flags)
+
+poll3 = poll2                           # Alias for backward compatibility
+
+def loop(timeout=30.0, use_poll=False, map=None, count=None):
+    if map is None:
+        map = socket_map
+
+    if use_poll and hasattr(select, 'poll'):
+        poll_fun = poll2
+    else:
+        poll_fun = poll
+
+    if count is None:
+        while map:
+            poll_fun(timeout, map)
+
+    else:
+        while map and count > 0:
+            poll_fun(timeout, map)
+            count = count - 1
+
+class dispatcher:
+
+    debug = False
+    connected = False
+    accepting = False
+    closing = False
+    addr = None
+
+    def __init__(self, sock=None, map=None):
+        if map is None:
+            self._map = socket_map
+        else:
+            self._map = map
+
+        if sock:
+            self.set_socket(sock, map)
+            # I think it should inherit this anyway
+            self.socket.setblocking(0)
+            self.connected = True
+            # XXX Does the constructor require that the socket passed
+            # be connected?
+            try:
+                self.addr = sock.getpeername()
+            except socket.error:
+                # The addr isn't crucial
+                pass
+        else:
+            self.socket = None
+
+    def __repr__(self):
+        status = [self.__class__.__module__+"."+self.__class__.__name__]
+        if self.accepting and self.addr:
+            status.append('listening')
+        elif self.connected:
+            status.append('connected')
+        if self.addr is not None:
+            try:
+                status.append('%s:%d' % self.addr)
+            except TypeError:
+                status.append(repr(self.addr))
+        return '<%s at %#x>' % (' '.join(status), id(self))
+
+    def add_channel(self, map=None):
+        #self.log_info('adding channel %s' % self)
+        if map is None:
+            map = self._map
+        map[self._fileno] = self
+
+    def del_channel(self, map=None):
+        fd = self._fileno
+        if map is None:
+            map = self._map
+        if map.has_key(fd):
+            #self.log_info('closing channel %d:%s' % (fd, self))
+            del map[fd]
+        self._fileno = None
+
+    def create_socket(self, family, type):
+        self.family_and_type = family, type
+        self.socket = socket.socket(family, type)
+        self.socket.setblocking(0)
+        self._fileno = self.socket.fileno()
+        self.add_channel()
+
+    def set_socket(self, sock, map=None):
+        self.socket = sock
+##        self.__dict__['socket'] = sock
+        self._fileno = sock.fileno()
+        self.add_channel(map)
+
+    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 socket.error:
+            pass
+
+    # ==================================================
+    # predicates for select()
+    # these are used as filters for the lists of sockets
+    # to pass to select().
+    # ==================================================
+
+    def readable(self):
+        return True
+
+    def writable(self):
+        return True
+
+    # ==================================================
+    # socket object methods.
+    # ==================================================
+
+    def listen(self, num):
+        self.accepting = True
+        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):
+        self.connected = False
+        err = self.socket.connect_ex(address)
+        # XXX Should interpret Winsock return values
+        if err in (EINPROGRESS, EALREADY, EWOULDBLOCK):
+            return
+        if err in (0, EISCONN):
+            self.addr = address
+            self.connected = True
+            self.handle_connect()
+        else:
+            raise socket.error, (err, errorcode[err])
+
+    def accept(self):
+        # XXX can return either an address pair or None
+        try:
+            conn, addr = self.socket.accept()
+            return conn, addr
+        except socket.error, why:
+            if why[0] == EWOULDBLOCK:
+                pass
+            else:
+                raise
+
+    def send(self, data):
+        try:
+            result = self.socket.send(data)
+            return result
+        except socket.error, why:
+            if why[0] == EWOULDBLOCK:
+                return 0
+            else:
+                raise
+            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, ESHUTDOWN]:
+                self.handle_close()
+                return ''
+            else:
+                raise
+
+    def close(self):
+        self.del_channel()
+        self.socket.close()
+
+    # cheap inheritance, used to pass all other attribute
+    # references to the underlying socket object.
+    def __getattr__(self, attr):
+        return getattr(self.socket, attr)
+
+    # log and log_info may be overridden to provide more sophisticated
+    # logging and warning methods. In general, log is for 'hit' logging
+    # and 'log_info' is for informational, warning and error logging.
+
+    def log(self, message):
+        sys.stderr.write('log: %s\n' % str(message))
+
+    def log_info(self, message, type='info'):
+        if __debug__ or type != 'info':
+            print '%s: %s' % (type, 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 = True
+            self.handle_accept()
+        elif not self.connected:
+            self.handle_connect()
+            self.connected = True
+            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 = True
+        self.handle_write()
+
+    def handle_expt_event(self):
+        self.handle_expt()
+
+    def handle_error(self):
+        nil, t, v, tbinfo = compact_traceback()
+
+        # sometimes a user repr method will crash.
+        try:
+            self_repr = repr(self)
+        except:
+            self_repr = '<__repr__(self) failed for object at %0x>' % id(self)
+
+        self.log_info(
+            'uncaptured python exception, closing channel %s (%s:%s %s)' % (
+                self_repr,
+                t,
+                v,
+                tbinfo
+                ),
+            'error'
+            )
+        self.close()
+
+    def handle_expt(self):
+        self.log_info('unhandled exception', 'warning')
+
+    def handle_read(self):
+        self.log_info('unhandled read event', 'warning')
+
+    def handle_write(self):
+        self.log_info('unhandled write event', 'warning')
+
+    def handle_connect(self):
+        self.log_info('unhandled connect event', 'warning')
+
+    def handle_accept(self):
+        self.log_info('unhandled accept event', 'warning')
+
+    def handle_close(self):
+        self.log_info('unhandled close event', 'warning')
+        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, map=None):
+        dispatcher.__init__(self, sock, map)
+        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_info('sending %s' % repr(data))
+        self.out_buffer = self.out_buffer + data
+        self.initiate_send()
+
+# ---------------------------------------------------------------------------
+# used for debugging.
+# ---------------------------------------------------------------------------
+
+def compact_traceback():
+    t, v, tb = sys.exc_info()
+    tbinfo = []
+    assert tb # Must have a traceback
+    while tb:
+        tbinfo.append((
+            tb.tb_frame.f_code.co_filename,
+            tb.tb_frame.f_code.co_name,
+            str(tb.tb_lineno)
+            ))
+        tb = tb.tb_next
+
+    # just to be safe
+    del tb
+
+    file, function, line = tbinfo[-1]
+    info = ' '.join(['[%s|%s|%s]' % x for x in tbinfo])
+    return (file, function, line), t, v, info
+
+def close_all(map=None):
+    if map is None:
+        map = socket_map
+    for x in map.values():
+        x.socket.close()
+    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 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...
+
+if os.name == 'posix':
+    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 os.read(self.fd, *args)
+
+        def send(self, *args):
+            return os.write(self.fd, *args)
+
+        read = recv
+        write = send
+
+        def close(self):
+            os.close(self.fd)
+
+        def fileno(self):
+            return self.fd
+
+    class file_dispatcher(dispatcher):
+
+        def __init__(self, fd, map=None):
+            dispatcher.__init__(self, None, map)
+            self.connected = True
+            self.set_file(fd)
+            # set it to non-blocking mode
+            flags = fcntl.fcntl(fd, fcntl.F_GETFL, 0)
+            flags = flags | os.O_NONBLOCK
+            fcntl.fcntl(fd, fcntl.F_SETFL, flags)
+
+        def set_file(self, fd):
+            self._fileno = fd
+            self.socket = file_wrapper(fd)
+            self.add_channel()