# Wrapper module for _socket, providing some additional facilities
This module provides socket operations and some related functions.
On Unix, it supports IP (Internet Protocol) and Unix domain sockets.
On other systems, it only supports IP. Functions specific for a
socket are available as methods of the socket object.
socket() -- create a new socket object
socketpair() -- create a pair of new socket objects [*]
fromfd() -- create a socket object from an open file descriptor [*]
gethostname() -- return the current hostname
gethostbyname() -- map a hostname to its IP number
gethostbyaddr() -- map an IP number or hostname to DNS info
getservbyname() -- map a service name and a protocol name to a port number
getprotobyname() -- map a protocol name (e.g. 'tcp') to a number
ntohs(), ntohl() -- convert 16, 32 bit int from network to host byte order
htons(), htonl() -- convert 16, 32 bit int from host to network byte order
inet_aton() -- convert IP addr string (123.45.67.89) to 32-bit packed format
inet_ntoa() -- convert 32-bit packed format IP to string (123.45.67.89)
ssl() -- secure socket layer support (only available if configured)
socket.getdefaulttimeout() -- get the default timeout value
socket.setdefaulttimeout() -- set the default timeout value
create_connection() -- connects to an address, with an optional timeout and
[*] not available on all platforms!
SocketType -- type object for socket objects
error -- exception raised for I/O errors
has_ipv6 -- boolean value indicating if IPv6 is supported
AF_INET, AF_UNIX -- socket domains (first argument to socket() call)
SOCK_STREAM, SOCK_DGRAM, SOCK_RAW -- socket types (second argument)
Many other constants may be defined; these may be used in calls to
the setsockopt() and getsockopt() methods.
from functools import partial
from types import MethodType
def ssl(sock, keyfile=None, certfile=None):
# we do an internal import here because the ssl
# module imports the socket module
warnings.warn("socket.ssl() is deprecated. Use ssl.wrap_socket() instead.",
DeprecationWarning, stacklevel=2)
return _realssl.sslwrap_simple(sock, keyfile, certfile)
# we need to import the same constants we used to...
from _ssl import SSLError as sslerror
SSL_ERROR_WANT_X509_LOOKUP, \
SSL_ERROR_WANT_CONNECT, \
SSL_ERROR_INVALID_ERROR_CODE
from _ssl import RAND_egd
# LibreSSL does not provide RAND_egd
from cStringIO import StringIO
from StringIO import StringIO
EBADF = getattr(errno, 'EBADF', 9)
EINTR = getattr(errno, 'EINTR', 4)
__all__ = ["getfqdn", "create_connection"]
__all__.extend(os._get_exports_list(_socket))
if sys.platform.lower().startswith("win"):
errorTab[10004] = "The operation was interrupted."
errorTab[10009] = "A bad file handle was passed."
errorTab[10013] = "Permission denied."
errorTab[10014] = "A fault occurred on the network??" # WSAEFAULT
errorTab[10022] = "An invalid operation was attempted."
errorTab[10035] = "The socket operation would block"
errorTab[10036] = "A blocking operation is already in progress."
errorTab[10048] = "The network address is in use."
errorTab[10054] = "The connection has been reset."
errorTab[10058] = "The network has been shut down."
errorTab[10060] = "The operation timed out."
errorTab[10061] = "Connection refused."
errorTab[10063] = "The name is too long."
errorTab[10064] = "The host is down."
errorTab[10065] = "The host is unreachable."
__all__.append("errorTab")
"""Get fully qualified domain name from name.
An empty argument is interpreted as meaning the local host.
First the hostname returned by gethostbyaddr() is checked, then
possibly existing aliases. In case no FQDN is available, hostname
from gethostname() is returned.
if not name or name == '0.0.0.0':
hostname, aliases, ipaddrs = gethostbyaddr(name)
aliases.insert(0, hostname)
'bind', 'connect', 'connect_ex', 'fileno', 'listen',
'getpeername', 'getsockname', 'getsockopt', 'setsockopt',
'sendall', 'setblocking',
'settimeout', 'gettimeout', 'shutdown')
_socketmethods = _socketmethods + ('ioctl',)
if sys.platform == "riscos":
_socketmethods = _socketmethods + ('sleeptaskw',)
# All the method names that must be delegated to either the real socket
# object or the _closedsocket object.
_delegate_methods = ("recv", "recvfrom", "recv_into", "recvfrom_into",
class _closedsocket(object):
raise error(EBADF, 'Bad file descriptor')
# All _delegate_methods must also be initialized here.
send = recv = recv_into = sendto = recvfrom = recvfrom_into = _dummy
# Wrapper around platform socket objects. This implements
# a platform-independent dup() functionality. The
# implementation currently relies on reference counting
# to close the underlying socket object.
class _socketobject(object):
__doc__ = _realsocket.__doc__
__slots__ = ["_sock", "__weakref__"] + list(_delegate_methods)
def __init__(self, family=AF_INET, type=SOCK_STREAM, proto=0, _sock=None):
_sock = _realsocket(family, type, proto)
for method in _delegate_methods:
setattr(self, method, getattr(_sock, method))
def close(self, _closedsocket=_closedsocket,
_delegate_methods=_delegate_methods, setattr=setattr):
# This function should not reference any globals. See issue #808164.
self._sock = _closedsocket()
dummy = self._sock._dummy
for method in _delegate_methods:
setattr(self, method, dummy)
close.__doc__ = _realsocket.close.__doc__
sock, addr = self._sock.accept()
return _socketobject(_sock=sock), addr
accept.__doc__ = _realsocket.accept.__doc__
"""dup() -> socket object
Return a new socket object connected to the same system resource."""
return _socketobject(_sock=self._sock)
def makefile(self, mode='r', bufsize=-1):
"""makefile([mode[, bufsize]]) -> file object
Return a regular file object corresponding to the socket. The mode
and bufsize arguments are as for the built-in open() function."""
return _fileobject(self._sock, mode, bufsize)
family = property(lambda self: self._sock.family, doc="the socket family")
type = property(lambda self: self._sock.type, doc="the socket type")
proto = property(lambda self: self._sock.proto, doc="the socket protocol")
def meth(name,self,*args):
return getattr(self._sock,name)(*args)
for _m in _socketmethods:
p.__doc__ = getattr(_realsocket,_m).__doc__
m = MethodType(p,None,_socketobject)
setattr(_socketobject,_m,m)
socket = SocketType = _socketobject
class _fileobject(object):
"""Faux file object attached to a socket object."""
__slots__ = ["mode", "bufsize", "softspace",
# "closed" is a property, see below
"_sock", "_rbufsize", "_wbufsize", "_rbuf", "_wbuf", "_wbuf_len",
def __init__(self, sock, mode='rb', bufsize=-1, close=False):
self.mode = mode # Not actually used in this version
bufsize = self.default_bufsize
# _rbufsize is the suggested recv buffer size. It is *strictly*
# obeyed within readline() for recv calls. If it is larger than
# default_bufsize it will be used for recv calls within read().
self._rbufsize = self.default_bufsize
# We use StringIO for the read buffer to avoid holding a list
# of variously sized string objects which have been known to
# fragment the heap due to how they are malloc()ed and often
# realloc()ed down much smaller than their original allocation.
self._wbuf = [] # A list of strings
return self._sock is None
closed = property(_getclosed, doc="True if the file is closed")
# close() may fail if __init__ didn't complete
data = "".join(self._wbuf)
buffer_size = max(self._rbufsize, self.default_bufsize)
while write_offset < data_size:
self._sock.sendall(view[write_offset:write_offset+buffer_size])
write_offset += buffer_size
if write_offset < data_size:
remainder = data[write_offset:]
del view, data # explicit free
self._wbuf.append(remainder)
self._wbuf_len = len(remainder)
return self._sock.fileno()
data = str(data) # XXX Should really reject non-string non-buffers
self._wbuf_len += len(data)
if (self._wbufsize == 0 or
(self._wbufsize == 1 and '\n' in data) or
(self._wbufsize > 1 and self._wbuf_len >= self._wbufsize)):
def writelines(self, list):
# XXX We could do better here for very long lists
# XXX Should really reject non-string non-buffers
lines = filter(None, map(str, list))
self._wbuf_len += sum(map(len, lines))
if (self._wbufsize <= 1 or
self._wbuf_len >= self._wbufsize):
# Use max, disallow tiny reads in a loop as they are very inefficient.
# We never leave read() with any leftover data from a new recv() call
# in our internal buffer.
rbufsize = max(self._rbufsize, self.default_bufsize)
# Our use of StringIO rather than lists of string objects returned by
# recv() minimizes memory usage and fragmentation that occurs when
# rbufsize is large compared to the typical return value of recv().
buf.seek(0, 2) # seek end
self._rbuf = StringIO() # reset _rbuf. we consume it via buf.
data = self._sock.recv(rbufsize)
# Read until size bytes or EOF seen, whichever comes first
# Already have size bytes in our buffer? Extract and return.
self._rbuf.write(buf.read())
self._rbuf = StringIO() # reset _rbuf. we consume it via buf.
# recv() will malloc the amount of memory given as its
# parameter even though it often returns much less data
# than that. The returned data string is short lived
# as we copy it into a StringIO and free it. This avoids
# fragmentation issues on many platforms.
data = self._sock.recv(left)
if n == size and not buf_len:
# Shortcut. Avoid buffer data copies when:
# - We have no data in our buffer.
# - Our call to recv returned exactly the
# number of bytes we were asked to read.
assert n <= left, "recv(%d) returned %d bytes" % (left, n)
#assert buf_len == buf.tell()
def readline(self, size=-1):
buf.seek(0, 2) # seek end
# check if we already have it in our buffer
bline = buf.readline(size)
if bline.endswith('\n') or len(bline) == size:
self._rbuf.write(buf.read())
# Read until \n or EOF, whichever comes first
# Speed up unbuffered case
self._rbuf = StringIO() # reset _rbuf. we consume it via buf.
# The try..except to catch EINTR was moved outside the
# recv loop to avoid the per byte overhead.
buf.seek(0, 2) # seek end
self._rbuf = StringIO() # reset _rbuf. we consume it via buf.
data = self._sock.recv(self._rbufsize)
self._rbuf.write(data[nl:])
# Read until size bytes or \n or EOF seen, whichever comes first
buf.seek(0, 2) # seek end
self._rbuf.write(buf.read())
self._rbuf = StringIO() # reset _rbuf. we consume it via buf.
data = self._sock.recv(self._rbufsize)
# did we just receive a newline?
nl = data.find('\n', 0, left)
# save the excess data to _rbuf
self._rbuf.write(data[nl:])
# Shortcut. Avoid data copy through buf when returning
# a substring of our first recv().