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Diffstat (limited to 'lib-python/3/socket.py')
| -rw-r--r-- | lib-python/3/socket.py | 406 |
1 files changed, 406 insertions, 0 deletions
diff --git a/lib-python/3/socket.py b/lib-python/3/socket.py new file mode 100644 index 0000000000..1e285493c4 --- /dev/null +++ b/lib-python/3/socket.py @@ -0,0 +1,406 @@ +# 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() -- 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) +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 + optional source address. + + [*] 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 * + +import os, sys, io + +try: + import errno +except ImportError: + errno = None +EBADF = getattr(errno, 'EBADF', 9) +EINTR = getattr(errno, 'EINTR', 4) +EAGAIN = getattr(errno, 'EAGAIN', 11) +EWOULDBLOCK = getattr(errno, 'EWOULDBLOCK', 11) + +__all__ = ["getfqdn", "create_connection"] +__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") + + +class socket(_socket.socket): + + """A subclass of _socket.socket adding the makefile() method.""" + + __slots__ = ["__weakref__", "_io_refs", "_closed"] + + def __init__(self, family=AF_INET, type=SOCK_STREAM, proto=0, fileno=None): + _socket.socket.__init__(self, family, type, proto, fileno) + self._io_refs = 0 + self._closed = False + + def __enter__(self): + return self + + def __exit__(self, *args): + if not self._closed: + self.close() + + def __repr__(self): + """Wrap __repr__() to reveal the real class name.""" + s = _socket.socket.__repr__(self) + if s.startswith("<socket object"): + s = "<%s.%s%s%s" % (self.__class__.__module__, + self.__class__.__name__, + getattr(self, '_closed', False) and " [closed] " or "", + s[7:]) + return s + + def dup(self): + """dup() -> socket object + + Return a new socket object connected to the same system resource. + """ + fd = dup(self.fileno()) + sock = self.__class__(self.family, self.type, self.proto, fileno=fd) + sock.settimeout(self.gettimeout()) + return sock + + def accept(self): + """accept() -> (socket object, address info) + + Wait for an incoming connection. Return a new socket + representing the connection, and the address of the client. + For IP sockets, the address info is a pair (hostaddr, port). + """ + fd, addr = self._accept() + sock = socket(self.family, self.type, self.proto, fileno=fd) + # Issue #7995: if no default timeout is set and the listening + # socket had a (non-zero) timeout, force the new socket in blocking + # mode to override platform-specific socket flags inheritance. + if getdefaulttimeout() is None and self.gettimeout(): + sock.setblocking(True) + return sock, addr + + def makefile(self, mode="r", buffering=None, *, + encoding=None, errors=None, newline=None): + """makefile(...) -> an I/O stream connected to the socket + + The arguments are as for io.open() after the filename, + except the only mode characters supported are 'r', 'w' and 'b'. + The semantics are similar too. (XXX refactor to share code?) + """ + for c in mode: + if c not in {"r", "w", "b"}: + raise ValueError("invalid mode %r (only r, w, b allowed)") + writing = "w" in mode + reading = "r" in mode or not writing + assert reading or writing + binary = "b" in mode + rawmode = "" + if reading: + rawmode += "r" + if writing: + rawmode += "w" + raw = SocketIO(self, rawmode) + self._io_refs += 1 + if buffering is None: + buffering = -1 + if buffering < 0: + buffering = io.DEFAULT_BUFFER_SIZE + if buffering == 0: + if not binary: + raise ValueError("unbuffered streams must be binary") + return raw + if reading and writing: + buffer = io.BufferedRWPair(raw, raw, buffering) + elif reading: + buffer = io.BufferedReader(raw, buffering) + else: + assert writing + buffer = io.BufferedWriter(raw, buffering) + if binary: + return buffer + text = io.TextIOWrapper(buffer, encoding, errors, newline) + text.mode = mode + return text + + def _decref_socketios(self): + if self._io_refs > 0: + self._io_refs -= 1 + if self._closed: + self.close() + + def _real_close(self, _ss=_socket.socket): + # This function should not reference any globals. See issue #808164. + _ss.close(self) + + def close(self): + # This function should not reference any globals. See issue #808164. + self._closed = True + if self._io_refs <= 0: + self._real_close() + +def fromfd(fd, family, type, proto=0): + """ fromfd(fd, family, type[, proto]) -> socket object + + Create a socket object from a duplicate of the given file + descriptor. The remaining arguments are the same as for socket(). + """ + nfd = dup(fd) + return socket(family, type, proto, nfd) + + +if hasattr(_socket, "socketpair"): + + def socketpair(family=None, type=SOCK_STREAM, proto=0): + """socketpair([family[, type[, proto]]]) -> (socket object, socket object) + + Create a pair of socket objects from the sockets returned by the platform + socketpair() function. + The arguments are the same as for socket() except the default family is + AF_UNIX if defined on the platform; otherwise, the default is AF_INET. + """ + if family is None: + try: + family = AF_UNIX + except NameError: + family = AF_INET + a, b = _socket.socketpair(family, type, proto) + a = socket(family, type, proto, a.detach()) + b = socket(family, type, proto, b.detach()) + return a, b + + +_blocking_errnos = { EAGAIN, EWOULDBLOCK } + +class SocketIO(io.RawIOBase): + + """Raw I/O implementation for stream sockets. + + This class supports the makefile() method on sockets. It provides + the raw I/O interface on top of a socket object. + """ + + # One might wonder why not let FileIO do the job instead. There are two + # main reasons why FileIO is not adapted: + # - it wouldn't work under Windows (where you can't used read() and + # write() on a socket handle) + # - it wouldn't work with socket timeouts (FileIO would ignore the + # timeout and consider the socket non-blocking) + + # XXX More docs + + def __init__(self, sock, mode): + if mode not in ("r", "w", "rw", "rb", "wb", "rwb"): + raise ValueError("invalid mode: %r" % mode) + io.RawIOBase.__init__(self) + self._sock = sock + if "b" not in mode: + mode += "b" + self._mode = mode + self._reading = "r" in mode + self._writing = "w" in mode + self._timeout_occurred = False + + def readinto(self, b): + """Read up to len(b) bytes into the writable buffer *b* and return + the number of bytes read. If the socket is non-blocking and no bytes + are available, None is returned. + + If *b* is non-empty, a 0 return value indicates that the connection + was shutdown at the other end. + """ + self._checkClosed() + self._checkReadable() + if self._timeout_occurred: + raise IOError("cannot read from timed out object") + while True: + try: + return self._sock.recv_into(b) + except timeout: + self._timeout_occurred = True + raise + except error as e: + n = e.args[0] + if n == EINTR: + continue + if n in _blocking_errnos: + return None + raise + + def write(self, b): + """Write the given bytes or bytearray object *b* to the socket + and return the number of bytes written. This can be less than + len(b) if not all data could be written. If the socket is + non-blocking and no bytes could be written None is returned. + """ + self._checkClosed() + self._checkWritable() + try: + return self._sock.send(b) + except error as e: + # XXX what about EINTR? + if e.args[0] in _blocking_errnos: + return None + raise + + def readable(self): + """True if the SocketIO is open for reading. + """ + return self._reading and not self.closed + + def writable(self): + """True if the SocketIO is open for writing. + """ + return self._writing and not self.closed + + def fileno(self): + """Return the file descriptor of the underlying socket. + """ + self._checkClosed() + return self._sock.fileno() + + @property + def name(self): + if not self.closed: + return self.fileno() + else: + return -1 + + @property + def mode(self): + return self._mode + + def close(self): + """Close the SocketIO object. This doesn't close the underlying + socket, except if all references to it have disappeared. + """ + if self.closed: + return + io.RawIOBase.close(self) + self._sock._decref_socketios() + self._sock = None + + +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 + + +_GLOBAL_DEFAULT_TIMEOUT = object() + +def create_connection(address, timeout=_GLOBAL_DEFAULT_TIMEOUT, + source_address=None): + """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. If *source_address* is set it must be a tuple of (host, port) + for the socket to bind as a source address before making the connection. + An host of '' or port 0 tells the OS to use the default. + """ + + host, port = address + err = None + 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) + if source_address: + sock.bind(source_address) + sock.connect(sa) + return sock + + except error as _: + err = _ + if sock is not None: + sock.close() + + if err is not None: + raise err + else: + raise error("getaddrinfo returns an empty list") |