# Wrapper module for _socket, providing some additional facilities

# implemented in Python.

"""\

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.

Functions:

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() -- mape 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

 [*] not available on all platforms!

Special objects:

SocketType -- type object for socket objects

error -- exception raised for I/O errors

has_ipv6 -- boolean value indicating if IPv6 is supported

Integer constants:

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.

"""

import _socket

from _socket import *

try:

    import _ssl

except ImportError:

    # no SSL support

    pass

else:

    def ssl(sock, keyfile=None, certfile=None):

        # we do an internal import here because the ssl

        # module imports the socket module

        import ssl as _realssl

        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

    from _ssl import \

         RAND_add, \

         RAND_egd, \

         RAND_status, \

         SSL_ERROR_ZERO_RETURN, \

         SSL_ERROR_WANT_READ, \

         SSL_ERROR_WANT_WRITE, \

         SSL_ERROR_WANT_X509_LOOKUP, \

         SSL_ERROR_SYSCALL, \

         SSL_ERROR_SSL, \

         SSL_ERROR_WANT_CONNECT, \

         SSL_ERROR_EOF, \

         SSL_ERROR_INVALID_ERROR_CODE

import os, sys, warnings

try:

    from cStringIO import StringIO

except ImportError:

    from StringIO import StringIO

try:

    from errno import EBADF

except ImportError:

    EBADF = 9

__all__ = ["getfqdn"]

__all__.extend(os._get_exports_list(_socket))

_realsocket = socket

# WSA error codes

if sys.platform.lower().startswith("win"):

    errorTab = {}

    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")

def getfqdn(name=''):

    """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.

    """

    name = name.strip()

    if not name or name == '0.0.0.0':

        name = gethostname()

    try:

        hostname, aliases, ipaddrs = gethostbyaddr(name)

    except error:

        pass

    else:

        aliases.insert(0, hostname)

        for name in aliases:

            if '.' in name:

                break

        else:

            name = hostname

    return name

_socketmethods = (

    'bind', 'connect', 'connect_ex', 'fileno', 'listen',

    'getpeername', 'getsockname', 'getsockopt', 'setsockopt',

    'sendall', 'setblocking',

    'settimeout', 'gettimeout', 'shutdown')

if os.name == "nt":

    _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",

                     "send", "sendto")

class _closedsocket(object):

    __slots__ = []

    def _dummy(*args):

        raise error(EBADF, 'Bad file descriptor')

    # All _delegate_methods must also be initialized here.

    send = recv = recv_into = sendto = recvfrom = recvfrom_into = _dummy

    __getattr__ = _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):

        if _sock is None:

            _sock = _realsocket(family, type, proto)

        self._sock = _sock

        for method in _delegate_methods:

            setattr(self, method, getattr(_sock, method))

    def close(self):

        self._sock = _closedsocket()

        dummy = self._sock._dummy

        for method in _delegate_methods:

            setattr(self, method, dummy)

    close.__doc__ = _realsocket.close.__doc__

    def accept(self):

        sock, addr = self._sock.accept()

        return _socketobject(_sock=sock), addr

    accept.__doc__ = _realsocket.accept.__doc__

    def dup(self):

        """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")

    _s = ("def %s(self, *args): return self._sock.%s(*args)\n\n"

          "%s.__doc__ = _realsocket.%s.__doc__\n")

    for _m in _socketmethods:

        exec _s % (_m, _m, _m, _m)

    del _m, _s

socket = SocketType = _socketobject

class _fileobject(object):

    """Faux file object attached to a socket object."""

    default_bufsize = 8192

    name = "<socket>"

    __slots__ = ["mode", "bufsize", "softspace",

                 # "closed" is a property, see below

                 "_sock", "_rbufsize", "_wbufsize", "_rbuf", "_wbuf",

                 "_close"]

    def __init__(self, sock, mode='rb', bufsize=-1, close=False):

        self._sock = sock

        self.mode = mode # Not actually used in this version

        if bufsize < 0:

            bufsize = self.default_bufsize

        self.bufsize = bufsize

        self.softspace = False

        # _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().

        if bufsize == 0:

            self._rbufsize = 1

        elif bufsize == 1:

            self._rbufsize = self.default_bufsize

        else:

            self._rbufsize = bufsize

        self._wbufsize = 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._rbuf = StringIO()

        self._wbuf = [] # A list of strings

        self._close = close

    def _getclosed(self):

        return self._sock is None

    closed = property(_getclosed, doc="True if the file is closed")

    def close(self):

        try:

            if self._sock:

                self.flush()

        finally:

            if self._close:

                self._sock.close()

            self._sock = None

    def __del__(self):

        try:

            self.close()

        except:

            # close() may fail if __init__ didn't complete

            pass

    def flush(self):

        if self._wbuf:

            buffer = "".join(self._wbuf)

            self._wbuf = []

            self._sock.sendall(buffer)

    def fileno(self):

        return self._sock.fileno()

    def write(self, data):

        data = str(data) # XXX Should really reject non-string non-buffers

        if not data:

            return

        self._wbuf.append(data)

        if (self._wbufsize == 0 or

            self._wbufsize == 1 and '\n' in data or

            self._get_wbuf_len() >= self._wbufsize):

            self.flush()

    def writelines(self, list):

        # XXX We could do better here for very long lists

        # XXX Should really reject non-string non-buffers

        self._wbuf.extend(filter(None, map(str, list)))

        if (self._wbufsize <= 1 or

            self._get_wbuf_len() >= self._wbufsize):

            self.flush()

    def _get_wbuf_len(self):

        buf_len = 0

        for x in self._wbuf:

            buf_len += len(x)

        return buf_len

    def read(self, size=-1):

        # 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 = self._rbuf

        buf.seek(0, 2)  # seek end

        if size < 0:

            # Read until EOF

            self._rbuf = StringIO()  # reset _rbuf.  we consume it via buf.

            while True:

                data = self._sock.recv(rbufsize)

                if not data:

                    break

                buf.write(data)

            return buf.getvalue()

        else:

            # Read until size bytes or EOF seen, whichever comes first

            buf_len = buf.tell()

            if buf_len >= size:

                # Already have size bytes in our buffer?  Extract and return.

                buf.seek(0)

                rv = buf.read(size)

                self._rbuf = StringIO()

                self._rbuf.write(buf.read())

                return rv

            self._rbuf = StringIO()  # reset _rbuf.  we consume it via buf.

            while True:

                left = size - buf_len

                # 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 not data:

                    break

                n = len(data)

                if n == size and not buf_len:

                    # Shortcut.  Avoid buffer data copies when:

                    # - We have no data in our buffer.

                    # AND

                    # - Our call to recv returned exactly the

                    #   number of bytes we were asked to read.

                    return data

                if n == left:

                    buf.write(data)

                    del data  # explicit free

                    break

                assert n <= left, "recv(%d) returned %d bytes" % (left, n)

                buf.write(data)

                buf_len += n

                del data  # explicit free

                #assert buf_len == buf.tell()

            return buf.getvalue()

    def readline(self, size=-1):

        buf = self._rbuf

        buf.seek(0, 2)  # seek end

        if buf.tell() > 0:

            # check if we already have it in our buffer

            buf.seek(0)

            bline = buf.readline(size)

            if bline.endswith('\n') or len(bline) == size:

                self._rbuf = StringIO()

                self._rbuf.write(buf.read())

                return bline

            del bline

        if size < 0:

            # Read until \n or EOF, whichever comes first

            if self._rbufsize <= 1:

                # Speed up unbuffered case

                buf.seek(0)

                buffers = [buf.read()]

                self._rbuf = StringIO()  # reset _rbuf.  we consume it via buf.

                data = None

                recv = self._sock.recv

                while data != "\n":

                    data = recv(1)

                    if not data:

                        break

                    buffers.append(data)

                return "".join(buffers)

            buf.seek(0, 2)  # seek end

            self._rbuf = StringIO()  # reset _rbuf.  we consume it via buf.

            while True:

                data = self._sock.recv(self._rbufsize)

                if not data:

                    break

                nl = data.find('\n')

                if nl >= 0:

                    nl += 1

                    buf.write(data[:nl])

                    self._rbuf.write(data[nl:])

                    del data

                    break

                buf.write(data)

            return buf.getvalue()

        else:

            # Read until size bytes or \n or EOF seen, whichever comes first

            buf.seek(0, 2)  # seek end

            buf_len = buf.tell()

            if buf_len >= size:

                buf.seek(0)

                rv = buf.read(size)

                self._rbuf = StringIO()

                self._rbuf.write(buf.read())

                return rv

            self._rbuf = StringIO()  # reset _rbuf.  we consume it via buf.

            while True:

                data = self._sock.recv(self._rbufsize)

                if not data:

                    break

                left = size - buf_len

                # did we just receive a newline?

                nl = data.find('\n', 0, left)

                if nl >= 0:

                    nl += 1

                    # save the excess data to _rbuf

                    self._rbuf.write(data[nl:])

                    if buf_len:

                        buf.write(data[:nl])

                        break

                    else:

                        # Shortcut.  Avoid data copy through buf when returning

                        # a substring of our first recv().

                        return data[:nl]

                n = len(data)

                if n == size and not buf_len:

                    # Shortcut.  Avoid data copy through buf when

                    # returning exactly all of our first recv().

                    return data

                if n >= left:

                    buf.write(data[:left])

                    self._rbuf.write(data[left:])

                    break

                buf.write(data)

                buf_len += n

                #assert buf_len == buf.tell()

            return buf.getvalue()

    def readlines(self, sizehint=0):

        total = 0

        list = []

        while True:

            line = self.readline()

            if not line:

                break

            list.append(line)

            total += len(line)

            if sizehint and total >= sizehint:

                break

        return list

    # Iterator protocols

    def __iter__(self):

        return self

    def next(self):

        line = self.readline()

        if not line:

            raise StopIteration

        return line

_GLOBAL_DEFAULT_TIMEOUT = object()

def create_connection(address, timeout=_GLOBAL_DEFAULT_TIMEOUT):

    """Connect to *address* and return the socket object.

    Convenience function.  Connect to *address* (a 2-tuple ``(host,

    port)``) and return the socket object.  Passing the optional

    *timeout* parameter will set the timeout on the socket instance

    before attempting to connect.  If no *timeout* is supplied, the

    global default timeout setting returned by :func:`getdefaulttimeout`

    is used.

    """

    msg = "getaddrinfo returns an empty list"

    host, port = address

    for res in getaddrinfo(host, port, 0, SOCK_STREAM):

        af, socktype, proto, canonname, sa = res

        sock = None

        try:

            sock = socket(af, socktype, proto)

            if timeout is not _GLOBAL_DEFAULT_TIMEOUT:

                sock.settimeout(timeout)

            sock.connect(sa)

            return sock

        except error, msg:

            if sock is not None:

                sock.close()

    raise error, msg