Files
deb-python-eventlet/eventlet/greenio.py
Sergey Shepelev 203e629212 PEP-8 fixes
2014-08-27 10:21:55 +04:00

683 lines
22 KiB
Python

import errno
import os
from socket import socket as _original_socket
import socket
import sys
import time
import warnings
from eventlet.support import get_errno, six
from eventlet.hubs import trampoline, notify_close, notify_opened, IOClosed
__all__ = ['GreenSocket', 'GreenPipe', 'shutdown_safe']
BUFFER_SIZE = 4096
CONNECT_ERR = set((errno.EINPROGRESS, errno.EALREADY, errno.EWOULDBLOCK))
CONNECT_SUCCESS = set((0, errno.EISCONN))
if sys.platform[:3] == "win":
CONNECT_ERR.add(errno.WSAEINVAL) # Bug 67
if six.PY3:
from io import IOBase as file
_fileobject = socket.SocketIO
elif six.PY2:
_fileobject = socket._fileobject
def socket_connect(descriptor, address):
"""
Attempts to connect to the address, returns the descriptor if it succeeds,
returns None if it needs to trampoline, and raises any exceptions.
"""
err = descriptor.connect_ex(address)
if err in CONNECT_ERR:
return None
if err not in CONNECT_SUCCESS:
raise socket.error(err, errno.errorcode[err])
return descriptor
def socket_checkerr(descriptor):
err = descriptor.getsockopt(socket.SOL_SOCKET, socket.SO_ERROR)
if err not in CONNECT_SUCCESS:
raise socket.error(err, errno.errorcode[err])
def socket_accept(descriptor):
"""
Attempts to accept() on the descriptor, returns a client,address tuple
if it succeeds; returns None if it needs to trampoline, and raises
any exceptions.
"""
try:
return descriptor.accept()
except socket.error as e:
if get_errno(e) == errno.EWOULDBLOCK:
return None
raise
if sys.platform[:3] == "win":
# winsock sometimes throws ENOTCONN
SOCKET_BLOCKING = set((errno.EAGAIN, errno.EWOULDBLOCK,))
SOCKET_CLOSED = set((errno.ECONNRESET, errno.ENOTCONN, errno.ESHUTDOWN))
else:
# oddly, on linux/darwin, an unconnected socket is expected to block,
# so we treat ENOTCONN the same as EWOULDBLOCK
SOCKET_BLOCKING = set((errno.EAGAIN, errno.EWOULDBLOCK, errno.ENOTCONN))
SOCKET_CLOSED = set((errno.ECONNRESET, errno.ESHUTDOWN, errno.EPIPE))
def set_nonblocking(fd):
"""
Sets the descriptor to be nonblocking. Works on many file-like
objects as well as sockets. Only sockets can be nonblocking on
Windows, however.
"""
try:
setblocking = fd.setblocking
except AttributeError:
# fd has no setblocking() method. It could be that this version of
# Python predates socket.setblocking(). In that case, we can still set
# the flag "by hand" on the underlying OS fileno using the fcntl
# module.
try:
import fcntl
except ImportError:
# Whoops, Windows has no fcntl module. This might not be a socket
# at all, but rather a file-like object with no setblocking()
# method. In particular, on Windows, pipes don't support
# non-blocking I/O and therefore don't have that method. Which
# means fcntl wouldn't help even if we could load it.
raise NotImplementedError("set_nonblocking() on a file object "
"with no setblocking() method "
"(Windows pipes don't support non-blocking I/O)")
# We managed to import fcntl.
fileno = fd.fileno()
orig_flags = fcntl.fcntl(fileno, fcntl.F_GETFL)
new_flags = orig_flags | os.O_NONBLOCK
if new_flags != orig_flags:
fcntl.fcntl(fileno, fcntl.F_SETFL, new_flags)
else:
# socket supports setblocking()
setblocking(0)
try:
from socket import _GLOBAL_DEFAULT_TIMEOUT
except ImportError:
_GLOBAL_DEFAULT_TIMEOUT = object()
class GreenSocket(object):
"""
Green version of socket.socket class, that is intended to be 100%
API-compatible.
It also recognizes the keyword parameter, 'set_nonblocking=True'.
Pass False to indicate that socket is already in non-blocking mode
to save syscalls.
"""
def __init__(self, family_or_realsock=socket.AF_INET, *args, **kwargs):
should_set_nonblocking = kwargs.pop('set_nonblocking', True)
if isinstance(family_or_realsock, six.integer_types):
fd = _original_socket(family_or_realsock, *args, **kwargs)
# Notify the hub that this is a newly-opened socket.
notify_opened(fd.fileno())
else:
fd = family_or_realsock
# import timeout from other socket, if it was there
try:
self._timeout = fd.gettimeout() or socket.getdefaulttimeout()
except AttributeError:
self._timeout = socket.getdefaulttimeout()
if should_set_nonblocking:
set_nonblocking(fd)
self.fd = fd
# when client calls setblocking(0) or settimeout(0) the socket must
# act non-blocking
self.act_non_blocking = False
# Copy some attributes from underlying real socket.
# This is the easiest way that i found to fix
# https://bitbucket.org/eventlet/eventlet/issue/136
# Only `getsockopt` is required to fix that issue, others
# are just premature optimization to save __getattr__ call.
self.bind = fd.bind
self.close = fd.close
self.fileno = fd.fileno
self.getsockname = fd.getsockname
self.getsockopt = fd.getsockopt
self.listen = fd.listen
self.setsockopt = fd.setsockopt
self.shutdown = fd.shutdown
self._closed = False
@property
def _sock(self):
return self
# Forward unknown attributes to fd, cache the value for future use.
# I do not see any simple attribute which could be changed
# so caching everything in self is fine.
# If we find such attributes - only attributes having __get__ might be cached.
# For now - I do not want to complicate it.
def __getattr__(self, name):
attr = getattr(self.fd, name)
setattr(self, name, attr)
return attr
def _trampoline(self, fd, read=False, write=False, timeout=None, timeout_exc=None):
""" We need to trampoline via the event hub.
We catch any signal back from the hub indicating that the operation we
were waiting on was associated with a filehandle that's since been
invalidated.
"""
if self._closed:
# If we did any logging, alerting to a second trampoline attempt on a closed
# socket here would be useful.
raise IOClosed()
try:
return trampoline(fd, read=read, write=write, timeout=timeout,
timeout_exc=timeout_exc,
mark_as_closed=self._mark_as_closed)
except IOClosed:
# This socket's been obsoleted. De-fang it.
self._mark_as_closed()
raise
def accept(self):
if self.act_non_blocking:
return self.fd.accept()
fd = self.fd
while True:
res = socket_accept(fd)
if res is not None:
client, addr = res
set_nonblocking(client)
return type(self)(client), addr
self._trampoline(fd, read=True, timeout=self.gettimeout(),
timeout_exc=socket.timeout("timed out"))
def _defanged_close(self):
# Already closed the once
pass
def _mark_as_closed(self):
""" Mark this socket as being closed """
self.close = self._defanged_close
self._closed = True
def close(self):
notify_close(self.fd)
self._mark_as_closed() # Don't do this twice.
return self.fd.close()
def __del__(self):
self.close()
def connect(self, address):
if self.act_non_blocking:
return self.fd.connect(address)
fd = self.fd
if self.gettimeout() is None:
while not socket_connect(fd, address):
try:
self._trampoline(fd, write=True)
except IOClosed:
raise socket.error(errno.EBADFD)
socket_checkerr(fd)
else:
end = time.time() + self.gettimeout()
while True:
if socket_connect(fd, address):
return
if time.time() >= end:
raise socket.timeout("timed out")
try:
self._trampoline(fd, write=True, timeout=end - time.time(),
timeout_exc=socket.timeout("timed out"))
except IOClosed:
# ... we need some workable errno here.
raise socket.error(errno.EBADFD)
socket_checkerr(fd)
def connect_ex(self, address):
if self.act_non_blocking:
return self.fd.connect_ex(address)
fd = self.fd
if self.gettimeout() is None:
while not socket_connect(fd, address):
try:
self._trampoline(fd, write=True)
socket_checkerr(fd)
except socket.error as ex:
return get_errno(ex)
except IOClosed:
return errno.EBADFD
else:
end = time.time() + self.gettimeout()
while True:
try:
if socket_connect(fd, address):
return 0
if time.time() >= end:
raise socket.timeout(errno.EAGAIN)
self._trampoline(fd, write=True, timeout=end - time.time(),
timeout_exc=socket.timeout(errno.EAGAIN))
socket_checkerr(fd)
except socket.error as ex:
return get_errno(ex)
except IOClosed:
return errno.EBADFD
def dup(self, *args, **kw):
sock = self.fd.dup(*args, **kw)
newsock = type(self)(sock, set_nonblocking=False)
newsock.settimeout(self.gettimeout())
return newsock
def makefile(self, *args, **kw):
dupped = self.dup()
res = _fileobject(dupped, *args, **kw)
if hasattr(dupped, "_drop"):
dupped._drop()
return res
def makeGreenFile(self, *args, **kw):
warnings.warn("makeGreenFile has been deprecated, please use "
"makefile instead", DeprecationWarning, stacklevel=2)
return self.makefile(*args, **kw)
def recv(self, buflen, flags=0):
fd = self.fd
if self.act_non_blocking:
return fd.recv(buflen, flags)
while True:
try:
return fd.recv(buflen, flags)
except socket.error as e:
if get_errno(e) in SOCKET_BLOCKING:
pass
elif get_errno(e) in SOCKET_CLOSED:
return ''
else:
raise
try:
self._trampoline(
fd,
read=True,
timeout=self.gettimeout(),
timeout_exc=socket.timeout("timed out"))
except IOClosed as e:
# Perhaps we should return '' instead?
raise EOFError()
def recvfrom(self, *args):
if not self.act_non_blocking:
self._trampoline(self.fd, read=True, timeout=self.gettimeout(),
timeout_exc=socket.timeout("timed out"))
return self.fd.recvfrom(*args)
def recvfrom_into(self, *args):
if not self.act_non_blocking:
self._trampoline(self.fd, read=True, timeout=self.gettimeout(),
timeout_exc=socket.timeout("timed out"))
return self.fd.recvfrom_into(*args)
def recv_into(self, *args):
if not self.act_non_blocking:
self._trampoline(self.fd, read=True, timeout=self.gettimeout(),
timeout_exc=socket.timeout("timed out"))
return self.fd.recv_into(*args)
def send(self, data, flags=0):
fd = self.fd
if self.act_non_blocking:
return fd.send(data, flags)
# blocking socket behavior - sends all, blocks if the buffer is full
total_sent = 0
len_data = len(data)
while 1:
try:
total_sent += fd.send(data[total_sent:], flags)
except socket.error as e:
if get_errno(e) not in SOCKET_BLOCKING:
raise
if total_sent == len_data:
break
try:
self._trampoline(self.fd, write=True, timeout=self.gettimeout(),
timeout_exc=socket.timeout("timed out"))
except IOClosed:
raise socket.error(errno.ECONNRESET, 'Connection closed by another thread')
return total_sent
def sendall(self, data, flags=0):
tail = self.send(data, flags)
len_data = len(data)
while tail < len_data:
tail += self.send(data[tail:], flags)
def sendto(self, *args):
self._trampoline(self.fd, write=True)
return self.fd.sendto(*args)
def setblocking(self, flag):
if flag:
self.act_non_blocking = False
self._timeout = None
else:
self.act_non_blocking = True
self._timeout = 0.0
def settimeout(self, howlong):
if howlong is None or howlong == _GLOBAL_DEFAULT_TIMEOUT:
self.setblocking(True)
return
try:
f = howlong.__float__
except AttributeError:
raise TypeError('a float is required')
howlong = f()
if howlong < 0.0:
raise ValueError('Timeout value out of range')
if howlong == 0.0:
self.act_non_blocking = True
self._timeout = 0.0
else:
self.act_non_blocking = False
self._timeout = howlong
def gettimeout(self):
return self._timeout
if "__pypy__" in sys.builtin_module_names:
def _reuse(self):
getattr(self.fd, '_sock', self.fd)._reuse()
def _drop(self):
getattr(self.fd, '_sock', self.fd)._drop()
class _SocketDuckForFd(object):
"""Class implementing all socket method used by _fileobject
in cooperative manner using low level os I/O calls.
"""
_refcount = 0
def __init__(self, fileno):
self._fileno = fileno
notify_opened(fileno)
self._closed = False
def _trampoline(self, fd, read=False, write=False, timeout=None, timeout_exc=None):
if self._closed:
# Don't trampoline if we're already closed.
raise IOClosed()
try:
return trampoline(fd, read=read, write=write, timeout=timeout,
timeout_exc=timeout_exc,
mark_as_closed=self._mark_as_closed)
except IOClosed:
# Our fileno has been obsoleted. Defang ourselves to
# prevent spurious closes.
self._mark_as_closed()
raise
def _defanged_close(self):
# Don't let anything close the wrong filehandle.
pass
def _mark_as_closed(self):
self.close = self._close = self._defanged_close
self._closed = True
@property
def _sock(self):
return self
def fileno(self):
return self._fileno
def recv(self, buflen):
while True:
try:
data = os.read(self._fileno, buflen)
return data
except OSError as e:
if get_errno(e) not in SOCKET_BLOCKING:
raise IOError(*e.args)
self._trampoline(self, read=True)
def recv_into(self, buf, nbytes=0, flags=0):
if nbytes == 0:
nbytes = len(buf)
data = self.recv(nbytes)
buf[:nbytes] = data
return len(data)
def send(self, data):
while True:
try:
os.write(self._fileno, data)
except OSError as e:
if get_errno(e) not in SOCKET_BLOCKING:
raise IOError(*e.args)
trampoline(self, write=True)
def sendall(self, data):
len_data = len(data)
os_write = os.write
fileno = self._fileno
try:
total_sent = os_write(fileno, data)
except OSError as e:
if get_errno(e) != errno.EAGAIN:
raise IOError(*e.args)
total_sent = 0
while total_sent < len_data:
self._trampoline(self, write=True)
try:
total_sent += os_write(fileno, data[total_sent:])
except OSError as e:
if get_errno(e) != errno. EAGAIN:
raise IOError(*e.args)
def __del__(self):
self._close()
def _close(self):
notify_close(self._fileno)
self._mark_as_closed()
try:
os.close(self._fileno)
except:
# os.close may fail if __init__ didn't complete
# (i.e file dscriptor passed to popen was invalid
pass
def __repr__(self):
return "%s:%d" % (self.__class__.__name__, self._fileno)
def _reuse(self):
self._refcount += 1
def _drop(self):
self._refcount -= 1
if self._refcount == 0:
self._close()
# Python3
_decref_socketios = _drop
def _operationOnClosedFile(*args, **kwargs):
raise ValueError("I/O operation on closed file")
class GreenPipe(_fileobject):
"""
GreenPipe is a cooperative replacement for file class.
It will cooperate on pipes. It will block on regular file.
Differneces from file class:
- mode is r/w property. Should re r/o
- encoding property not implemented
- write/writelines will not raise TypeError exception when non-string data is written
it will write str(data) instead
- Universal new lines are not supported and newlines property not implementeded
- file argument can be descriptor, file name or file object.
"""
def __init__(self, f, mode='r', bufsize=-1):
if not isinstance(f, six.string_types + (int, file)):
raise TypeError('f(ile) should be int, str, unicode or file, not %r' % f)
if isinstance(f, six.string_types):
f = open(f, mode, 0)
if isinstance(f, int):
fileno = f
self._name = "<fd:%d>" % fileno
else:
fileno = os.dup(f.fileno())
self._name = f.name
if f.mode != mode:
raise ValueError('file.mode %r does not match mode parameter %r' % (f.mode, mode))
self._name = f.name
f.close()
super(GreenPipe, self).__init__(_SocketDuckForFd(fileno), mode)
set_nonblocking(self)
self.softspace = 0
@property
def name(self):
return self._name
def __repr__(self):
return "<%s %s %r, mode %r at 0x%x>" % (
self.closed and 'closed' or 'open',
self.__class__.__name__,
self.name,
self.mode,
(id(self) < 0) and (sys.maxint + id(self)) or id(self))
def _defanged_close(self):
pass
def _mark_as_closed(self):
self.close = self._defanged_close
def close(self):
self._mark_as_closed()
super(GreenPipe, self).close()
for method in [
'fileno', 'flush', 'isatty', 'next', 'read', 'readinto',
'readline', 'readlines', 'seek', 'tell', 'truncate',
'write', 'xreadlines', '__iter__', '__next__', 'writelines']:
setattr(self, method, _operationOnClosedFile)
def __enter__(self):
return self
def __exit__(self, *args):
self.close()
def _get_readahead_len(self):
return len(self._rbuf.getvalue())
def _clear_readahead_buf(self):
len = self._get_readahead_len()
if len > 0:
self.read(len)
def tell(self):
self.flush()
try:
return os.lseek(self.fileno(), 0, 1) - self._get_readahead_len()
except OSError as e:
raise IOError(*e.args)
def seek(self, offset, whence=0):
self.flush()
if whence == 1 and offset == 0: # tell synonym
return self.tell()
if whence == 1: # adjust offset by what is read ahead
offset -= self._get_readahead_len()
try:
rv = os.lseek(self.fileno(), offset, whence)
except OSError as e:
raise IOError(*e.args)
else:
self._clear_readahead_buf()
return rv
if getattr(file, "truncate", None): # not all OSes implement truncate
def truncate(self, size=-1):
self.flush()
if size == -1:
size = self.tell()
try:
rv = os.ftruncate(self.fileno(), size)
except OSError as e:
raise IOError(*e.args)
else:
self.seek(size) # move position&clear buffer
return rv
def isatty(self):
try:
return os.isatty(self.fileno())
except OSError as e:
raise IOError(*e.args)
# import SSL module here so we can refer to greenio.SSL.exceptionclass
try:
from OpenSSL import SSL
except ImportError:
# pyOpenSSL not installed, define exceptions anyway for convenience
class SSL(object):
class WantWriteError(Exception):
pass
class WantReadError(Exception):
pass
class ZeroReturnError(Exception):
pass
class SysCallError(Exception):
pass
def shutdown_safe(sock):
""" Shuts down the socket. This is a convenience method for
code that wants to gracefully handle regular sockets, SSL.Connection
sockets from PyOpenSSL and ssl.SSLSocket objects from Python 2.6
interchangeably. Both types of ssl socket require a shutdown() before
close, but they have different arity on their shutdown method.
Regular sockets don't need a shutdown before close, but it doesn't hurt.
"""
try:
try:
# socket, ssl.SSLSocket
return sock.shutdown(socket.SHUT_RDWR)
except TypeError:
# SSL.Connection
return sock.shutdown()
except socket.error as e:
# we don't care if the socket is already closed;
# this will often be the case in an http server context
if get_errno(e) != errno.ENOTCONN:
raise