/Modules/socketmodule.c

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/* Socket module */

/*

This module provides an interface to Berkeley socket IPC.

Limitations:

- Only AF_INET, AF_INET6 and AF_UNIX address families are supported in a
  portable manner, though AF_PACKET and AF_NETLINK are supported under Linux.
- No read/write operations (use sendall/recv or makefile instead).
- Additional restrictions apply on some non-Unix platforms (compensated
  for by socket.py).

Module interface:

- socket.error: exception raised for socket specific errors
- socket.gaierror: exception raised for getaddrinfo/getnameinfo errors,
	a subclass of socket.error
- socket.herror: exception raised for gethostby* errors,
	a subclass of socket.error
- socket.fromfd(fd, family, type[, proto]) --> new socket object (created
        from an existing file descriptor)
- socket.gethostbyname(hostname) --> host IP address (string: 'dd.dd.dd.dd')
- socket.gethostbyaddr(IP address) --> (hostname, [alias, ...], [IP addr, ...])
- socket.gethostname() --> host name (string: 'spam' or 'spam.domain.com')
- socket.getprotobyname(protocolname) --> protocol number
- socket.getservbyname(servicename[, protocolname]) --> port number
- socket.getservbyport(portnumber[, protocolname]) --> service name
- socket.socket([family[, type [, proto]]]) --> new socket object
- socket.socketpair([family[, type [, proto]]]) --> (socket, socket)
- socket.ntohs(16 bit value) --> new int object
- socket.ntohl(32 bit value) --> new int object
- socket.htons(16 bit value) --> new int object
- socket.htonl(32 bit value) --> new int object
- socket.getaddrinfo(host, port [, family, socktype, proto, flags])
	--> List of (family, socktype, proto, canonname, sockaddr)
- socket.getnameinfo(sockaddr, flags) --> (host, port)
- socket.AF_INET, socket.SOCK_STREAM, etc.: constants from <socket.h>
- socket.has_ipv6: boolean value indicating if IPv6 is supported
- socket.inet_aton(IP address) -> 32-bit packed IP representation
- socket.inet_ntoa(packed IP) -> IP address string
- socket.getdefaulttimeout() -> None | float
- socket.setdefaulttimeout(None | float)
- an Internet socket address is a pair (hostname, port)
  where hostname can be anything recognized by gethostbyname()
  (including the dd.dd.dd.dd notation) and port is in host byte order
- where a hostname is returned, the dd.dd.dd.dd notation is used
- a UNIX domain socket address is a string specifying the pathname
- an AF_PACKET socket address is a tuple containing a string
  specifying the ethernet interface and an integer specifying
  the Ethernet protocol number to be received. For example:
  ("eth0",0x1234).  Optional 3rd,4th,5th elements in the tuple
  specify packet-type and ha-type/addr.

Local naming conventions:

- names starting with sock_ are socket object methods
- names starting with socket_ are module-level functions
- names starting with PySocket are exported through socketmodule.h

*/

#ifdef __APPLE__
  /*
   * inet_aton is not available on OSX 10.3, yet we want to use a binary
   * that was build on 10.4 or later to work on that release, weak linking
   * comes to the rescue.
   */
# pragma weak inet_aton
#endif

#include "Python.h"
#include "structmember.h"

#undef MAX
#define MAX(x, y) ((x) < (y) ? (y) : (x))

/* Socket object documentation */
PyDoc_STRVAR(sock_doc,
"socket([family[, type[, proto]]]) -> socket object\n\
\n\
Open a socket of the given type.  The family argument specifies the\n\
address family; it defaults to AF_INET.  The type argument specifies\n\
whether this is a stream (SOCK_STREAM, this is the default)\n\
or datagram (SOCK_DGRAM) socket.  The protocol argument defaults to 0,\n\
specifying the default protocol.  Keyword arguments are accepted.\n\
\n\
A socket object represents one endpoint of a network connection.\n\
\n\
Methods of socket objects (keyword arguments not allowed):\n\
\n\
accept() -- accept a connection, returning new socket and client address\n\
bind(addr) -- bind the socket to a local address\n\
close() -- close the socket\n\
connect(addr) -- connect the socket to a remote address\n\
connect_ex(addr) -- connect, return an error code instead of an exception\n\
dup() -- return a new socket object identical to the current one [*]\n\
fileno() -- return underlying file descriptor\n\
getpeername() -- return remote address [*]\n\
getsockname() -- return local address\n\
getsockopt(level, optname[, buflen]) -- get socket options\n\
gettimeout() -- return timeout or None\n\
listen(n) -- start listening for incoming connections\n\
makefile([mode, [bufsize]]) -- return a file object for the socket [*]\n\
recv(buflen[, flags]) -- receive data\n\
recv_into(buffer[, nbytes[, flags]]) -- receive data (into a buffer)\n\
recvfrom(buflen[, flags]) -- receive data and sender\'s address\n\
recvfrom_into(buffer[, nbytes, [, flags])\n\
  -- receive data and sender\'s address (into a buffer)\n\
sendall(data[, flags]) -- send all data\n\
send(data[, flags]) -- send data, may not send all of it\n\
sendto(data[, flags], addr) -- send data to a given address\n\
setblocking(0 | 1) -- set or clear the blocking I/O flag\n\
setsockopt(level, optname, value) -- set socket options\n\
settimeout(None | float) -- set or clear the timeout\n\
shutdown(how) -- shut down traffic in one or both directions\n\
\n\
 [*] not available on all platforms!");

/* XXX This is a terrible mess of platform-dependent preprocessor hacks.
   I hope some day someone can clean this up please... */

/* Hacks for gethostbyname_r().  On some non-Linux platforms, the configure
   script doesn't get this right, so we hardcode some platform checks below.
   On the other hand, not all Linux versions agree, so there the settings
   computed by the configure script are needed! */

#ifndef linux
# undef HAVE_GETHOSTBYNAME_R_3_ARG
# undef HAVE_GETHOSTBYNAME_R_5_ARG
# undef HAVE_GETHOSTBYNAME_R_6_ARG
#endif

#ifndef WITH_THREAD
# undef HAVE_GETHOSTBYNAME_R
#endif

#ifdef HAVE_GETHOSTBYNAME_R
# if defined(_AIX) || defined(__osf__)
#  define HAVE_GETHOSTBYNAME_R_3_ARG
# elif defined(__sun) || defined(__sgi)
#  define HAVE_GETHOSTBYNAME_R_5_ARG
# elif defined(linux)
/* Rely on the configure script */
# else
#  undef HAVE_GETHOSTBYNAME_R
# endif
#endif

#if !defined(HAVE_GETHOSTBYNAME_R) && defined(WITH_THREAD) && \
    !defined(MS_WINDOWS)
# define USE_GETHOSTBYNAME_LOCK
#endif

/* To use __FreeBSD_version */
#ifdef HAVE_SYS_PARAM_H
#include <sys/param.h>
#endif
/* On systems on which getaddrinfo() is believed to not be thread-safe,
   (this includes the getaddrinfo emulation) protect access with a lock. */
#if defined(WITH_THREAD) && (defined(__APPLE__) || \
    (defined(__FreeBSD__) && __FreeBSD_version+0 < 503000) || \
    defined(__OpenBSD__) || defined(__NetBSD__) || \
    defined(__VMS) || !defined(HAVE_GETADDRINFO))
#define USE_GETADDRINFO_LOCK
#endif

#ifdef USE_GETADDRINFO_LOCK
#define ACQUIRE_GETADDRINFO_LOCK PyThread_acquire_lock(netdb_lock, 1);
#define RELEASE_GETADDRINFO_LOCK PyThread_release_lock(netdb_lock);
#else
#define ACQUIRE_GETADDRINFO_LOCK
#define RELEASE_GETADDRINFO_LOCK
#endif

#if defined(USE_GETHOSTBYNAME_LOCK) || defined(USE_GETADDRINFO_LOCK)
# include "pythread.h"
#endif

#if defined(PYCC_VACPP)
# include <types.h>
# include <io.h>
# include <sys/ioctl.h>
# include <utils.h>
# include <ctype.h>
#endif

#if defined(__VMS)
#  include <ioctl.h>
#endif

#if defined(PYOS_OS2)
# define  INCL_DOS
# define  INCL_DOSERRORS
# define  INCL_NOPMAPI
# include <os2.h>
#endif

#if defined(__sgi) && _COMPILER_VERSION>700 && !_SGIAPI
/* make sure that the reentrant (gethostbyaddr_r etc)
   functions are declared correctly if compiling with
   MIPSPro 7.x in ANSI C mode (default) */

/* XXX Using _SGIAPI is the wrong thing,
   but I don't know what the right thing is. */
#undef _SGIAPI /* to avoid warning */
#define _SGIAPI 1

#undef _XOPEN_SOURCE
#include <sys/socket.h>
#include <sys/types.h>
#include <netinet/in.h>
#ifdef _SS_ALIGNSIZE
#define HAVE_GETADDRINFO 1
#define HAVE_GETNAMEINFO 1
#endif

#define HAVE_INET_PTON
#include <netdb.h>
#endif

/* Irix 6.5 fails to define this variable at all. This is needed
   for both GCC and SGI's compiler. I'd say that the SGI headers
   are just busted. Same thing for Solaris. */
#if (defined(__sgi) || defined(sun)) && !defined(INET_ADDRSTRLEN)
#define INET_ADDRSTRLEN 16
#endif

/* Generic includes */
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif

/* Generic socket object definitions and includes */
#define PySocket_BUILDING_SOCKET
#include "socketmodule.h"

/* Addressing includes */

#ifndef MS_WINDOWS

/* Non-MS WINDOWS includes */
# include <netdb.h>

/* Headers needed for inet_ntoa() and inet_addr() */
# ifdef __BEOS__
#  include <net/netdb.h>
# elif defined(PYOS_OS2) && defined(PYCC_VACPP)
#  include <netdb.h>
typedef size_t socklen_t;
# else
#   include <arpa/inet.h>
# endif

# ifndef RISCOS
#  include <fcntl.h>
# else
#  include <sys/ioctl.h>
#  include <socklib.h>
#  define NO_DUP
int h_errno; /* not used */
#  define INET_ADDRSTRLEN 16
# endif

#else

/* MS_WINDOWS includes */
# ifdef HAVE_FCNTL_H
#  include <fcntl.h>
# endif

#endif

#include <stddef.h>

#ifndef offsetof
# define offsetof(type, member)	((size_t)(&((type *)0)->member))
#endif

#ifndef O_NONBLOCK
# define O_NONBLOCK O_NDELAY
#endif

/* include Python's addrinfo.h unless it causes trouble */
#if defined(__sgi) && _COMPILER_VERSION>700 && defined(_SS_ALIGNSIZE)
  /* Do not include addinfo.h on some newer IRIX versions.
   * _SS_ALIGNSIZE is defined in sys/socket.h by 6.5.21,
   * for example, but not by 6.5.10.
   */
#elif defined(_MSC_VER) && _MSC_VER>1201
  /* Do not include addrinfo.h for MSVC7 or greater. 'addrinfo' and
   * EAI_* constants are defined in (the already included) ws2tcpip.h.
   */
#else
#  include "addrinfo.h"
#endif

#ifndef HAVE_INET_PTON
int inet_pton(int af, const char *src, void *dst);
const char *inet_ntop(int af, const void *src, char *dst, socklen_t size);
#endif

#ifdef __APPLE__
/* On OS X, getaddrinfo returns no error indication of lookup
   failure, so we must use the emulation instead of the libinfo
   implementation. Unfortunately, performing an autoconf test
   for this bug would require DNS access for the machine performing
   the configuration, which is not acceptable. Therefore, we
   determine the bug just by checking for __APPLE__. If this bug
   gets ever fixed, perhaps checking for sys/version.h would be
   appropriate, which is 10/0 on the system with the bug. */
#ifndef HAVE_GETNAMEINFO
/* This bug seems to be fixed in Jaguar. Ths easiest way I could
   Find to check for Jaguar is that it has getnameinfo(), which
   older releases don't have */
#undef HAVE_GETADDRINFO
#endif

#ifdef HAVE_INET_ATON
#define USE_INET_ATON_WEAKLINK
#endif

#endif

/* I know this is a bad practice, but it is the easiest... */
#if !defined(HAVE_GETADDRINFO)
/* avoid clashes with the C library definition of the symbol. */
#define getaddrinfo fake_getaddrinfo
#define gai_strerror fake_gai_strerror
#define freeaddrinfo fake_freeaddrinfo
#include "getaddrinfo.c"
#endif
#if !defined(HAVE_GETNAMEINFO)
#define getnameinfo fake_getnameinfo
#include "getnameinfo.c"
#endif

#if defined(MS_WINDOWS) || defined(__BEOS__)
/* BeOS suffers from the same socket dichotomy as Win32... - [cjh] */
/* seem to be a few differences in the API */
#define SOCKETCLOSE closesocket
#define NO_DUP /* Actually it exists on NT 3.5, but what the heck... */
#endif

#ifdef MS_WIN32
#define EAFNOSUPPORT WSAEAFNOSUPPORT
#define snprintf _snprintf
#endif

#if defined(PYOS_OS2) && !defined(PYCC_GCC)
#define SOCKETCLOSE soclose
#define NO_DUP /* Sockets are Not Actual File Handles under OS/2 */
#endif

#ifndef SOCKETCLOSE
#define SOCKETCLOSE close
#endif

#if defined(HAVE_BLUETOOTH_H) || defined(HAVE_BLUETOOTH_BLUETOOTH_H)
#define USE_BLUETOOTH 1
#if defined(__FreeBSD__)
#define BTPROTO_L2CAP BLUETOOTH_PROTO_L2CAP
#define BTPROTO_RFCOMM BLUETOOTH_PROTO_RFCOMM
#define sockaddr_l2 sockaddr_l2cap
#define sockaddr_rc sockaddr_rfcomm
#define _BT_L2_MEMB(sa, memb) ((sa)->l2cap_##memb)
#define _BT_RC_MEMB(sa, memb) ((sa)->rfcomm_##memb)
#elif defined(__NetBSD__)
#define sockaddr_l2 sockaddr_bt
#define sockaddr_rc sockaddr_bt
#define sockaddr_sco sockaddr_bt
#define _BT_L2_MEMB(sa, memb) ((sa)->bt_##memb)
#define _BT_RC_MEMB(sa, memb) ((sa)->bt_##memb)
#define _BT_SCO_MEMB(sa, memb) ((sa)->bt_##memb)
#else
#define _BT_L2_MEMB(sa, memb) ((sa)->l2_##memb)
#define _BT_RC_MEMB(sa, memb) ((sa)->rc_##memb)
#define _BT_SCO_MEMB(sa, memb) ((sa)->sco_##memb)
#endif
#endif

#ifdef __VMS
/* TCP/IP Services for VMS uses a maximum send/recv buffer length */
#define SEGMENT_SIZE (32 * 1024 -1)
#endif

#define	SAS2SA(x)	((struct sockaddr *)(x))

/*
 * Constants for getnameinfo()
 */
#if !defined(NI_MAXHOST)
#define NI_MAXHOST 1025
#endif
#if !defined(NI_MAXSERV)
#define NI_MAXSERV 32
#endif

/* XXX There's a problem here: *static* functions are not supposed to have
   a Py prefix (or use CapitalizedWords).  Later... */

/* Global variable holding the exception type for errors detected
   by this module (but not argument type or memory errors, etc.). */
static PyObject *socket_error;
static PyObject *socket_herror;
static PyObject *socket_gaierror;
static PyObject *socket_timeout;

#ifdef RISCOS
/* Global variable which is !=0 if Python is running in a RISC OS taskwindow */
static int taskwindow;
#endif

/* A forward reference to the socket type object.
   The sock_type variable contains pointers to various functions,
   some of which call new_sockobject(), which uses sock_type, so
   there has to be a circular reference. */
static PyTypeObject sock_type;

#if defined(HAVE_POLL_H)
#include <poll.h>
#elif defined(HAVE_SYS_POLL_H)
#include <sys/poll.h>
#endif

#ifdef Py_SOCKET_FD_CAN_BE_GE_FD_SETSIZE
/* Platform can select file descriptors beyond FD_SETSIZE */
#define IS_SELECTABLE(s) 1
#elif defined(HAVE_POLL)
/* Instead of select(), we'll use poll() since poll() works on any fd. */
#define IS_SELECTABLE(s) 1
/* Can we call select() with this socket without a buffer overrun? */
#else
/* POSIX says selecting file descriptors beyond FD_SETSIZE
   has undefined behaviour.  If there's no timeout left, we don't have to
   call select, so it's a safe, little white lie. */
#define IS_SELECTABLE(s) ((s)->sock_fd < FD_SETSIZE || s->sock_timeout <= 0.0)
#endif

static PyObject*
select_error(void)
{
	PyErr_SetString(socket_error, "unable to select on socket");
	return NULL;
}

/* Convenience function to raise an error according to errno
   and return a NULL pointer from a function. */

static PyObject *
set_error(void)
{
#ifdef MS_WINDOWS
	int err_no = WSAGetLastError();
	static struct {
		int no;
		const char *msg;
	} *msgp, msgs[] = {
		{WSAEINTR, "Interrupted system call"},
		{WSAEBADF, "Bad file descriptor"},
		{WSAEACCES, "Permission denied"},
		{WSAEFAULT, "Bad address"},
		{WSAEINVAL, "Invalid argument"},
		{WSAEMFILE, "Too many open files"},
		{WSAEWOULDBLOCK,
		  "The socket operation could not complete "
		  "without blocking"},
		{WSAEINPROGRESS, "Operation now in progress"},
		{WSAEALREADY, "Operation already in progress"},
		{WSAENOTSOCK, "Socket operation on non-socket"},
		{WSAEDESTADDRREQ, "Destination address required"},
		{WSAEMSGSIZE, "Message too long"},
		{WSAEPROTOTYPE, "Protocol wrong type for socket"},
		{WSAENOPROTOOPT, "Protocol not available"},
		{WSAEPROTONOSUPPORT, "Protocol not supported"},
		{WSAESOCKTNOSUPPORT, "Socket type not supported"},
		{WSAEOPNOTSUPP, "Operation not supported"},
		{WSAEPFNOSUPPORT, "Protocol family not supported"},
		{WSAEAFNOSUPPORT, "Address family not supported"},
		{WSAEADDRINUSE, "Address already in use"},
		{WSAEADDRNOTAVAIL, "Can't assign requested address"},
		{WSAENETDOWN, "Network is down"},
		{WSAENETUNREACH, "Network is unreachable"},
		{WSAENETRESET, "Network dropped connection on reset"},
		{WSAECONNABORTED, "Software caused connection abort"},
		{WSAECONNRESET, "Connection reset by peer"},
		{WSAENOBUFS, "No buffer space available"},
		{WSAEISCONN, "Socket is already connected"},
		{WSAENOTCONN, "Socket is not connected"},
		{WSAESHUTDOWN, "Can't send after socket shutdown"},
		{WSAETOOMANYREFS, "Too many references: can't splice"},
		{WSAETIMEDOUT, "Operation timed out"},
		{WSAECONNREFUSED, "Connection refused"},
		{WSAELOOP, "Too many levels of symbolic links"},
		{WSAENAMETOOLONG, "File name too long"},
		{WSAEHOSTDOWN, "Host is down"},
		{WSAEHOSTUNREACH, "No route to host"},
		{WSAENOTEMPTY, "Directory not empty"},
		{WSAEPROCLIM, "Too many processes"},
		{WSAEUSERS, "Too many users"},
		{WSAEDQUOT, "Disc quota exceeded"},
		{WSAESTALE, "Stale NFS file handle"},
		{WSAEREMOTE, "Too many levels of remote in path"},
		{WSASYSNOTREADY, "Network subsystem is unvailable"},
		{WSAVERNOTSUPPORTED, "WinSock version is not supported"},
		{WSANOTINITIALISED,
		  "Successful WSAStartup() not yet performed"},
		{WSAEDISCON, "Graceful shutdown in progress"},
		/* Resolver errors */
		{WSAHOST_NOT_FOUND, "No such host is known"},
		{WSATRY_AGAIN, "Host not found, or server failed"},
		{WSANO_RECOVERY, "Unexpected server error encountered"},
		{WSANO_DATA, "Valid name without requested data"},
		{WSANO_ADDRESS, "No address, look for MX record"},
		{0, NULL}
	};
	if (err_no) {
		PyObject *v;
		const char *msg = "winsock error";

		for (msgp = msgs; msgp->msg; msgp++) {
			if (err_no == msgp->no) {
				msg = msgp->msg;
				break;
			}
		}

		v = Py_BuildValue("(is)", err_no, msg);
		if (v != NULL) {
			PyErr_SetObject(socket_error, v);
			Py_DECREF(v);
		}
		return NULL;
	}
	else
#endif

#if defined(PYOS_OS2) && !defined(PYCC_GCC)
	if (sock_errno() != NO_ERROR) {
		APIRET rc;
		ULONG  msglen;
		char outbuf[100];
		int myerrorcode = sock_errno();

		/* Retrieve socket-related error message from MPTN.MSG file */
		rc = DosGetMessage(NULL, 0, outbuf, sizeof(outbuf),
				   myerrorcode - SOCBASEERR + 26,
				   "mptn.msg",
				   &msglen);
		if (rc == NO_ERROR) {
			PyObject *v;

			/* OS/2 doesn't guarantee a terminator */
			outbuf[msglen] = '\0';
			if (strlen(outbuf) > 0) {
				/* If non-empty msg, trim CRLF */
				char *lastc = &outbuf[ strlen(outbuf)-1 ];
				while (lastc > outbuf &&
				       isspace(Py_CHARMASK(*lastc))) {
					/* Trim trailing whitespace (CRLF) */
					*lastc-- = '\0';
				}
			}
			v = Py_BuildValue("(is)", myerrorcode, outbuf);
			if (v != NULL) {
				PyErr_SetObject(socket_error, v);
				Py_DECREF(v);
			}
			return NULL;
		}
	}
#endif

#if defined(RISCOS)
	if (_inet_error.errnum != NULL) {
		PyObject *v;
		v = Py_BuildValue("(is)", errno, _inet_err());
		if (v != NULL) {
			PyErr_SetObject(socket_error, v);
			Py_DECREF(v);
		}
		return NULL;
	}
#endif

	return PyErr_SetFromErrno(socket_error);
}


static PyObject *
set_herror(int h_error)
{
	PyObject *v;

#ifdef HAVE_HSTRERROR
	v = Py_BuildValue("(is)", h_error, (char *)hstrerror(h_error));
#else
	v = Py_BuildValue("(is)", h_error, "host not found");
#endif
	if (v != NULL) {
		PyErr_SetObject(socket_herror, v);
		Py_DECREF(v);
	}

	return NULL;
}


static PyObject *
set_gaierror(int error)
{
	PyObject *v;

#ifdef EAI_SYSTEM
	/* EAI_SYSTEM is not available on Windows XP. */
	if (error == EAI_SYSTEM)
		return set_error();
#endif

#ifdef HAVE_GAI_STRERROR
	v = Py_BuildValue("(is)", error, gai_strerror(error));
#else
	v = Py_BuildValue("(is)", error, "getaddrinfo failed");
#endif
	if (v != NULL) {
		PyErr_SetObject(socket_gaierror, v);
		Py_DECREF(v);
	}

	return NULL;
}

#ifdef __VMS
/* Function to send in segments */
static int
sendsegmented(int sock_fd, char *buf, int len, int flags)
{
	int n = 0;
	int remaining = len;

	while (remaining > 0) {
		unsigned int segment;

		segment = (remaining >= SEGMENT_SIZE ? SEGMENT_SIZE : remaining);
		n = send(sock_fd, buf, segment, flags);
		if (n < 0) {
			return n;
		}
		remaining -= segment;
		buf += segment;
	} /* end while */

	return len;
}
#endif

/* Function to perform the setting of socket blocking mode
   internally. block = (1 | 0). */
static int
internal_setblocking(PySocketSockObject *s, int block)
{
#ifndef RISCOS
#ifndef MS_WINDOWS
	int delay_flag;
#endif
#endif

	Py_BEGIN_ALLOW_THREADS
#ifdef __BEOS__
	block = !block;
	setsockopt(s->sock_fd, SOL_SOCKET, SO_NONBLOCK,
		   (void *)(&block), sizeof(int));
#else
#ifndef RISCOS
#ifndef MS_WINDOWS
#if defined(PYOS_OS2) && !defined(PYCC_GCC)
	block = !block;
	ioctl(s->sock_fd, FIONBIO, (caddr_t)&block, sizeof(block));
#elif defined(__VMS)
	block = !block;
	ioctl(s->sock_fd, FIONBIO, (unsigned int *)&block);
#else  /* !PYOS_OS2 && !__VMS */
	delay_flag = fcntl(s->sock_fd, F_GETFL, 0);
	if (block)
		delay_flag &= (~O_NONBLOCK);
	else
		delay_flag |= O_NONBLOCK;
	fcntl(s->sock_fd, F_SETFL, delay_flag);
#endif /* !PYOS_OS2 */
#else /* MS_WINDOWS */
	block = !block;
	ioctlsocket(s->sock_fd, FIONBIO, (u_long*)&block);
#endif /* MS_WINDOWS */
#else /* RISCOS */
	block = !block;
	socketioctl(s->sock_fd, FIONBIO, (u_long*)&block);
#endif /* RISCOS */
#endif /* __BEOS__ */
	Py_END_ALLOW_THREADS

	/* Since these don't return anything */
	return 1;
}

/* Do a select()/poll() on the socket, if necessary (sock_timeout > 0).
   The argument writing indicates the direction.
   This does not raise an exception; we'll let our caller do that
   after they've reacquired the interpreter lock.
   Returns 1 on timeout, -1 on error, 0 otherwise. */
static int
internal_select(PySocketSockObject *s, int writing)
{
	int n;

	/* Nothing to do unless we're in timeout mode (not non-blocking) */
	if (s->sock_timeout <= 0.0)
		return 0;

	/* Guard against closed socket */
	if (s->sock_fd < 0)
		return 0;

	/* Prefer poll, if available, since you can poll() any fd
	 * which can't be done with select(). */
#ifdef HAVE_POLL
	{
		struct pollfd pollfd;
		int timeout;

		pollfd.fd = s->sock_fd;
		pollfd.events = writing ? POLLOUT : POLLIN;

		/* s->sock_timeout is in seconds, timeout in ms */
		timeout = (int)(s->sock_timeout * 1000 + 0.5); 
		n = poll(&pollfd, 1, timeout);
	}
#else
	{
		/* Construct the arguments to select */
		fd_set fds;
		struct timeval tv;
		tv.tv_sec = (int)s->sock_timeout;
		tv.tv_usec = (int)((s->sock_timeout - tv.tv_sec) * 1e6);
		FD_ZERO(&fds);
		FD_SET(s->sock_fd, &fds);

		/* See if the socket is ready */
		if (writing)
			n = select(s->sock_fd+1, NULL, &fds, NULL, &tv);
		else
			n = select(s->sock_fd+1, &fds, NULL, NULL, &tv);
	}
#endif
	
	if (n < 0)
		return -1;
	if (n == 0)
		return 1;
	return 0;
}

/* Initialize a new socket object. */

static double defaulttimeout = -1.0; /* Default timeout for new sockets */

PyMODINIT_FUNC
init_sockobject(PySocketSockObject *s,
		SOCKET_T fd, int family, int type, int proto)
{
#ifdef RISCOS
	int block = 1;
#endif
	s->sock_fd = fd;
	s->sock_family = family;
	s->sock_type = type;
	s->sock_proto = proto;
	s->sock_timeout = defaulttimeout;

	s->errorhandler = &set_error;

	if (defaulttimeout >= 0.0)
		internal_setblocking(s, 0);

#ifdef RISCOS
	if (taskwindow)
		socketioctl(s->sock_fd, 0x80046679, (u_long*)&block);
#endif
}


/* Create a new socket object.
   This just creates the object and initializes it.
   If the creation fails, return NULL and set an exception (implicit
   in NEWOBJ()). */

static PySocketSockObject *
new_sockobject(SOCKET_T fd, int family, int type, int proto)
{
	PySocketSockObject *s;
	s = (PySocketSockObject *)
		PyType_GenericNew(&sock_type, NULL, NULL);
	if (s != NULL)
		init_sockobject(s, fd, family, type, proto);
	return s;
}


/* Lock to allow python interpreter to continue, but only allow one
   thread to be in gethostbyname or getaddrinfo */
#if defined(USE_GETHOSTBYNAME_LOCK) || defined(USE_GETADDRINFO_LOCK)
PyThread_type_lock netdb_lock;
#endif


/* Convert a string specifying a host name or one of a few symbolic
   names to a numeric IP address.  This usually calls gethostbyname()
   to do the work; the names "" and "<broadcast>" are special.
   Return the length (IPv4 should be 4 bytes), or negative if
   an error occurred; then an exception is raised. */

static int
setipaddr(char *name, struct sockaddr *addr_ret, size_t addr_ret_size, int af)
{
	struct addrinfo hints, *res;
	int error;
	int d1, d2, d3, d4;
	char ch;

	memset((void *) addr_ret, '\0', sizeof(*addr_ret));
	if (name[0] == '\0') {
		int siz;
		memset(&hints, 0, sizeof(hints));
		hints.ai_family = af;
		hints.ai_socktype = SOCK_DGRAM;	/*dummy*/
		hints.ai_flags = AI_PASSIVE;
		Py_BEGIN_ALLOW_THREADS
		ACQUIRE_GETADDRINFO_LOCK
		error = getaddrinfo(NULL, "0", &hints, &res);
		Py_END_ALLOW_THREADS
		/* We assume that those thread-unsafe getaddrinfo() versions
		   *are* safe regarding their return value, ie. that a
		   subsequent call to getaddrinfo() does not destroy the
		   outcome of the first call. */
		RELEASE_GETADDRINFO_LOCK
		if (error) {
			set_gaierror(error);
			return -1;
		}
		switch (res->ai_family) {
		case AF_INET:
			siz = 4;
			break;
#ifdef ENABLE_IPV6
		case AF_INET6:
			siz = 16;
			break;
#endif
		default:
			freeaddrinfo(res);
			PyErr_SetString(socket_error,
				"unsupported address family");
			return -1;
		}
		if (res->ai_next) {
			freeaddrinfo(res);
			PyErr_SetString(socket_error,
				"wildcard resolved to multiple address");
			return -1;
		}
		if (res->ai_addrlen < addr_ret_size)
			addr_ret_size = res->ai_addrlen;
		memcpy(addr_ret, res->ai_addr, addr_ret_size);
		freeaddrinfo(res);
		return siz;
	}
	if (name[0] == '<' && strcmp(name, "<broadcast>") == 0) {
		struct sockaddr_in *sin;
		if (af != AF_INET && af != AF_UNSPEC) {
			PyErr_SetString(socket_error,
				"address family mismatched");
			return -1;
		}
		sin = (struct sockaddr_in *)addr_ret;
		memset((void *) sin, '\0', sizeof(*sin));
		sin->sin_family = AF_INET;
#ifdef HAVE_SOCKADDR_SA_LEN
		sin->sin_len = sizeof(*sin);
#endif
		sin->sin_addr.s_addr = INADDR_BROADCAST;
		return sizeof(sin->sin_addr);
	}
	if (sscanf(name, "%d.%d.%d.%d%c", &d1, &d2, &d3, &d4, &ch) == 4 &&
	    0 <= d1 && d1 <= 255 && 0 <= d2 && d2 <= 255 &&
	    0 <= d3 && d3 <= 255 && 0 <= d4 && d4 <= 255) {
		struct sockaddr_in *sin;
		sin = (struct sockaddr_in *)addr_ret;
		sin->sin_addr.s_addr = htonl(
			((long) d1 << 24) | ((long) d2 << 16) |
			((long) d3 << 8) | ((long) d4 << 0));
		sin->sin_family = AF_INET;
#ifdef HAVE_SOCKADDR_SA_LEN
		sin->sin_len = sizeof(*sin);
#endif
		return 4;
	}
	memset(&hints, 0, sizeof(hints));
	hints.ai_family = af;
	Py_BEGIN_ALLOW_THREADS
	ACQUIRE_GETADDRINFO_LOCK
	error = getaddrinfo(name, NULL, &hints, &res);
#if defined(__digital__) && defined(__unix__)
	if (error == EAI_NONAME && af == AF_UNSPEC) {
		/* On Tru64 V5.1, numeric-to-addr conversion fails
		   if no address family is given. Assume IPv4 for now.*/
		hints.ai_family = AF_INET;
		error = getaddrinfo(name, NULL, &hints, &res);
	}
#endif
	Py_END_ALLOW_THREADS
	RELEASE_GETADDRINFO_LOCK  /* see comment in setipaddr() */
	if (error) {
		set_gaierror(error);
		return -1;
	}
	if (res->ai_addrlen < addr_ret_size)
		addr_ret_size = res->ai_addrlen;
	memcpy((char *) addr_ret, res->ai_addr, addr_ret_size);
	freeaddrinfo(res);
	switch (addr_ret->sa_family) {
	case AF_INET:
		return 4;
#ifdef ENABLE_IPV6
	case AF_INET6:
		return 16;
#endif
	default:
		PyErr_SetString(socket_error, "unknown address family");
		return -1;
	}
}


/* Create a string object representing an IP address.
   This is always a string of the form 'dd.dd.dd.dd' (with variable
   size numbers). */

static PyObject *
makeipaddr(struct sockaddr *addr, int addrlen)
{
	char buf[NI_MAXHOST];
	int error;

	error = getnameinfo(addr, addrlen, buf, sizeof(buf), NULL, 0,
		NI_NUMERICHOST);
	if (error) {
		set_gaierror(error);
		return NULL;
	}
	return PyString_FromString(buf);
}


#ifdef USE_BLUETOOTH
/* Convert a string representation of a Bluetooth address into a numeric
   address.  Returns the length (6), or raises an exception and returns -1 if
   an error occurred. */

static int
setbdaddr(char *name, bdaddr_t *bdaddr)
{
	unsigned int b0, b1, b2, b3, b4, b5;
	char ch;
	int n;

	n = sscanf(name, "%X:%X:%X:%X:%X:%X%c",
		   &b5, &b4, &b3, &b2, &b1, &b0, &ch);
	if (n == 6 && (b0 | b1 | b2 | b3 | b4 | b5) < 256) {
		bdaddr->b[0] = b0;
		bdaddr->b[1] = b1;
		bdaddr->b[2] = b2;
		bdaddr->b[3] = b3;
		bdaddr->b[4] = b4;
		bdaddr->b[5] = b5;
		return 6;
	} else {
		PyErr_SetString(socket_error, "bad bluetooth address");
		return -1;
	}
}

/* Create a string representation of the Bluetooth address.  This is always a
   string of the form 'XX:XX:XX:XX:XX:XX' where XX is a two digit hexadecimal
   value (zero padded if necessary). */

static PyObject *
makebdaddr(bdaddr_t *bdaddr)
{
	char buf[(6 * 2) + 5 + 1];

	sprintf(buf, "%02X:%02X:%02X:%02X:%02X:%02X",
		bdaddr->b[5], bdaddr->b[4], bdaddr->b[3],
		bdaddr->b[2], bdaddr->b[1], bdaddr->b[0]);
	return PyString_FromString(buf);
}
#endif


/* Create an object representing the given socket address,
   suitable for passing it back to bind(), connect() etc.
   The family field of the sockaddr structure is inspected
   to determine what kind of address it really is. */

/*ARGSUSED*/
static PyObject *
makesockaddr(int sockfd, struct sockaddr *addr, int addrlen, int proto)
{
	if (addrlen == 0) {
		/* No address -- may be recvfrom() from known socket */
		Py_INCREF(Py_None);
		return Py_None;
	}

#ifdef __BEOS__
	/* XXX: BeOS version of accept() doesn't set family correctly */
	addr->sa_family = AF_INET;
#endif

	switch (addr->sa_family) {

	case AF_INET:
	{
		struct sockaddr_in *a;
		PyObject *addrobj = makeipaddr(addr, sizeof(*a));
		PyObject *ret = NULL;
		if (addrobj) {
			a = (struct sockaddr_in *)addr;
			ret = Py_BuildValue("Oi", addrobj, ntohs(a->sin_port));
			Py_DECREF(addrobj);
		}
		return ret;
	}

#if defined(AF_UNIX)
	case AF_UNIX:
	{
		struct sockaddr_un *a = (struct sockaddr_un *) addr;
#ifdef linux
		if (a->sun_path[0] == 0) {  /* Linux abstract namespace */
			addrlen -= (sizeof(*a) - sizeof(a->sun_path));
			return PyString_FromStringAndSize(a->sun_path,
							  addrlen);
		}
		else
#endif /* linux */
		{
			/* regular NULL-terminated string */
			return PyString_FromString(a->sun_path);
		}
	}
#endif /* AF_UNIX */

#if defined(AF_NETLINK)
       case AF_NETLINK:
       {
               struct sockaddr_nl *a = (struct sockaddr_nl *) addr;
               return Py_BuildValue("II", a->nl_pid, a->nl_groups);
       }
#endif /* AF_NETLINK */

#ifdef ENABLE_IPV6
	case AF_INET6:
	{
		struct sockaddr_in6 *a;
		PyObject *addrobj = makeipaddr(addr, sizeof(*a));
		PyObject *ret = NULL;
		if (addrobj) {
			a = (struct sockaddr_in6 *)addr;
			ret = Py_BuildValue("Oiii",
					    addrobj,
					    ntohs(a->sin6_port),
					    a->sin6_flowinfo,
					    a->sin6_scope_id);
			Py_DECREF(addrobj);
		}
		return ret;
	}
#endif

#ifdef USE_BLUETOOTH
	case AF_BLUETOOTH:
		switch (proto) {

		case BTPROTO_L2CAP:
		{
			struct sockaddr_l2 *a = (struct sockaddr_l2 *) addr;
			PyObject *addrobj = makebdaddr(&_BT_L2_MEMB(a, bdaddr));
			PyObject *ret = NULL;
			if (addrobj) {
				ret = Py_BuildValue("Oi",
						    addrobj,
						    _BT_L2_MEMB(a, psm));
				Py_DECREF(addrobj);
			}
			return ret;
		}

		case BTPROTO_RFCOMM:
		{
			struct sockaddr_rc *a = (struct sockaddr_rc *) addr;
			PyObject *addrobj = makebdaddr(&_BT_RC_MEMB(a, bdaddr));
			PyObject *ret = NULL;
			if (addrobj) {
				ret = Py_BuildValue("Oi",
						    addrobj,
						    _BT_RC_MEMB(a, channel));
				Py_DECREF(addrobj);
			}
			return ret;
		}

#if !defined(__FreeBSD__)
		case BTPROTO_SCO:
		{
			struct sockaddr_sco *a = (struct sockaddr_sco *) addr;
			return makebdaddr(&_BT_SCO_MEMB(a, bdaddr));
		}
#endif

		}
#endif

#ifdef HAVE_NETPACKET_PACKET_H
	case AF_PACKET:
	{
		struct sockaddr_ll *a = (struct sockaddr_ll *)addr;
		char *ifname = "";
		struct ifreq ifr;
		/* need to look up interface name give index */
		if (a->sll_ifindex) {
			ifr.ifr_ifindex = a->sll_ifindex;
			if (ioctl(sockfd, SIOCGIFNAME, &ifr) == 0)
				ifname = ifr.ifr_name;
		}
		return Py_BuildValue("shbhs#",
				     ifname,
				     ntohs(a->sll_protocol),
				     a->sll_pkttype,
				     a->sll_hatype,
				     a->sll_addr,
				     a->sll_halen);
	}
#endif

	/* More cases here... */

	default:
		/* If we don't know the address family, don't raise an
		   exception -- return it as a tuple. */
		return Py_BuildValue("is#",
				     addr->sa_family,
				     addr->sa_data,
				     sizeof(addr->sa_data));

	}
}


/* Parse a socket address argument according to the socket object's
   address family.  Return 1 if the address was in the proper format,
   0 of not.  The address is returned through addr_ret, its length
   through len_ret. */

static int
getsockaddrarg(PySocketSockObject *s, PyObject *args,
	       struct sockaddr *addr_ret, int *len_ret)
{
	switch (s->sock_family) {

#if defined(AF_UNIX)
	case AF_UNIX:
	{
		struct sockaddr_un* addr;
		char *path;
		int len;
		if (!PyArg_Parse(args, "t#", &path, &len))
			return 0;

		addr = (struct sockaddr_un*)addr_ret;
#ifdef linux
		if (len > 0 && path[0] == 0) {
			/* Linux abstract namespace extension */
			if (len > sizeof addr->sun_path) {
				PyErr_SetString(socket_error,
						"AF_UNIX path too long");
				return 0;
			}
		}
		else
#endif /* linux */
                {
			/* regular NULL-terminated string */
			if (len >= sizeof addr->sun_path) {
				PyErr_SetString(socket_error,
						"AF_UNIX path too long");
				return 0;
			}
			addr->sun_path[len] = 0;
		}
		addr->sun_family = s->sock_family;
		memcpy(addr->sun_path, path, len);
#if defined(PYOS_OS2)
		*len_ret = sizeof(*addr);
#else
		*len_ret = len + sizeof(*addr) - sizeof(addr->sun_path);
#endif
		return 1;
	}
#endif /* AF_UNIX */

#if defined(AF_NETLINK)
	case AF_NETLINK:
	{
		struct sockaddr_nl* addr;
		int pid, groups;
		addr = (struct sockaddr_nl *)addr_ret;
		if (!PyTuple_Check(args)) {
			PyErr_Format(
				PyExc_TypeError,
				"getsockaddrarg: "
				"AF_NETLINK address must be tuple, not %.500s",
				args->ob_type->tp_name);
			return 0;
		}
		if (!PyArg_ParseTuple(args, "II:getsockaddrarg", &pid, &groups))
			return 0;
		addr->nl_family = AF_NETLINK;
		addr->nl_pid = pid;
		addr->nl_groups = groups;
		*len_ret = sizeof(*addr);
		return 1;
	}
#endif

	case AF_INET:
	{
		struct sockaddr_in* addr;
		char *host;
		int port, result;
		if (!PyTuple_Check(args)) {
			PyErr_Format(
				PyExc_TypeError,
				"getsockaddrarg: "
				"AF_INET address must be tuple, not %.500s",
				args->ob_type->tp_name);
			return 0;
		}
		if (!PyArg_ParseTuple(args, "eti:getsockaddrarg",
				      "idna", &host, &port))
			return 0;
		addr=(struct sockaddr_in*)addr_ret;
                result = setipaddr(host, (struct sockaddr *)addr,
                                   sizeof(*addr),  AF_INET);
                PyMem_Free(host);
                if (result < 0)
			return 0;
		addr->sin_family = AF_INET;
		addr->sin_port = htons((short)port);
		*len_ret = sizeof *addr;
		return 1;
	}

#ifdef ENABLE_IPV6
	case AF_INET6:
	{
		struct sockaddr_in6* addr;
		char *host;
		int port, flowinfo, scope_id, result;
		flowinfo = scope_id = 0;
		if (!PyTuple_Check(args)) {
			PyErr_Format(
				PyExc_TypeError,
				"getsockaddrarg: "
				"AF_INET6 address must be tuple, not %.500s",
				args->ob_type->tp_name);
			return 0;
		}
		if (!PyArg_ParseTuple(args, "eti|ii",
				      "idna", &host, &port, &flowinfo,
				      &scope_id)) {
			return 0;
		}
		addr = (struct sockaddr_in6*)addr_ret;
                result = setipaddr(host, (struct sockaddr *)addr,
                                   sizeof(*addr), AF_INET6);
                PyMem_Free(host);
                if (result < 0)
			return 0;
		addr->sin6_family = s->sock_family;
		addr->sin6_port = htons((short)port);
		addr->sin6_flowinfo = flowinfo;
		addr->sin6_scope_id = scope_id;
		*len_ret = sizeof *addr;
		return 1;
	}
#endif

#ifdef USE_BLUETOOTH
	case AF_BLUETOOTH:
	{
		switch (s->sock_proto) {
		case BTPROTO_L2CAP:
		{
			struct sockaddr_l2 *addr;
			char *straddr;

			addr = (struct sockaddr_l2 *)addr_ret;
			_BT_L2_MEMB(addr, family) = AF_BLUETOOTH;
			if (!PyArg_ParseTuple(args, "si", &straddr,
					      &_BT_L2_MEMB(addr, psm))) {
				PyErr_SetString(socket_error, "getsockaddrarg: "
						"wrong format");
				return 0;
			}
			if (setbdaddr(straddr, &_BT_L2_MEMB(addr, bdaddr)) < 0)
				return 0;

			*len_ret = sizeof *addr;
			return 1;
		}
		case BTPROTO_RFCOMM:
		{
			struct sockaddr_rc *addr;
			char *straddr;

			addr = (struct sockaddr_rc *)addr_ret;
			_BT_RC_MEMB(addr, family) = AF_BLUETOOTH;
			if (!PyArg_ParseTuple(args, "si", &straddr,
					      &_BT_RC_MEMB(addr, channel))) {
				PyErr_SetString(socket_error, "getsockaddrarg: "
						"wrong format");
				return 0;
			}
			if (setbdaddr(straddr, &_BT_RC_MEMB(addr, bdaddr)) < 0)
				return 0;

			*len_ret = sizeof *addr;
			return 1;
		}
#if !defined(__FreeBSD__)
		case BTPROTO_SCO:
		{
			struct sockaddr_sco *addr;
			char *straddr;

			addr = (struct sockaddr_sco *)addr_ret;
			_BT_SCO_MEMB(addr, family) = AF_BLUETOOTH;
			straddr = PyString_AsString(args);
			if (straddr == NULL) {
				PyErr_SetString(socket_error, "getsockaddrarg: "
						"wrong format");
				return 0;
			}
			if (setbdaddr(straddr, &_BT_SCO_MEMB(addr, bdaddr)) < 0)
				return 0;

			*len_ret = sizeof *addr;
			return 1;
		}
#endif
		default:
			PyErr_SetString(socket_error, "getsockaddrarg: unknown Bluetooth protocol");
			return 0;
		}
	}
#endif

#ifdef HAVE_NETPACKET_PACKET_H
	case AF_PACKET:
	{
		struct sockaddr_ll* addr;
		struct ifreq ifr;
		char *interfaceName;
		int protoNumber;
		int hatype = 0;
		int pkttype = 0;
		char *haddr = NULL;
		unsigned int halen = 0;

		if (!PyTuple_Check(args)) {
			PyErr_Format(
				PyExc_TypeError,
				"getsockaddrarg: "
				"AF_PACKET address must be tuple, not %.500s",
				args->ob_type->tp_name);
			return 0;
		}
		if (!PyArg_ParseTuple(args, "si|iis#", &interfaceName,
				      &protoNumber, &pkttype, &hatype,
				      &haddr, &halen))
			return 0;
		strncpy(ifr.ifr_name, interfaceName, sizeof(ifr.ifr_name));
		ifr.ifr_name[(sizeof(ifr.ifr_name))-1] = '\0';
		if (ioctl(s->sock_fd, SIOCGIFINDEX, &ifr) < 0) {
		        s->errorhandler();
			return 0;
		}
		if (halen > 8) {
		  PyErr_SetString(PyExc_ValueError,
				  "Hardware address must be 8 bytes or less");
		  return 0;
		}
		addr = (struct sockaddr_ll*)addr_ret;
		addr->sll_family = AF_PACKET;
		addr->sll_protocol = htons((short)protoNumber);
		addr->sll_ifindex = ifr.ifr_ifindex;
		addr->sll_pkttype = pkttype;
		addr->sll_hatype = hatype;
		if (halen != 0) {
		  memcpy(&addr->sll_addr, haddr, halen);
		}
		addr->sll_halen = halen;
		*len_ret = sizeof *addr;
		return 1;
	}
#endif

	/* More cases here... */

	default:
		PyErr_SetString(socket_error, "getsockaddrarg: bad family");
		return 0;

	}
}


/* Get the address length according to the socket object's address family.
   Return 1 if the family is known, 0 otherwise.  The length is returned
   through len_ret. */

static int
getsockaddrlen(PySocketSockObject *s, socklen_t *len_ret)
{
	switch (s->sock_family) {

#if defined(AF_UNIX)
	case AF_UNIX:
	{
		*len_ret = sizeof (struct sockaddr_un);
		return 1;
	}
#endif /* AF_UNIX */
#if defined(AF_NETLINK)
       case AF_NETLINK:
       {
               *len_ret = sizeof (struct sockaddr_nl);
               return 1;
       }
#endif

	case AF_INET:
	{
		*len_ret = sizeof (struct sockaddr_in);
		return 1;
	}

#ifdef ENABLE_IPV6
	case AF_INET6:
	{
		*len_ret = sizeof (struct sockaddr_in6);
		return 1;
	}
#endif

#ifdef USE_BLUETOOTH
	case AF_BLUETOOTH:
	{
		switch(s->sock_proto)
		{

		case BTPROTO_L2CAP:
			*len_ret = sizeof (struct sockaddr_l2);
			return 1;
		case BTPROTO_RFCOMM:
			*len_ret = sizeof (struct sockaddr_rc);
			return 1;
#if !defined(__FreeBSD__)
		case BTPROTO_SCO:
			*len_ret = sizeof (struct sockaddr_sco);
			return 1;
#endif
		default:
			PyErr_SetString(socket_error, "getsockaddrlen: "
					"unknown BT protocol");
			return 0;

		}
	}
#endif

#ifdef HAVE_NETPACKET_PACKET_H
	case AF_PACKET:
	{
		*len_ret = sizeof (struct sockaddr_ll);
		return 1;
	}
#endif

	/* More cases here... */

	default:
		PyErr_SetString(socket_error, "getsockaddrlen: bad family");
		return 0;

	}
}


/* s.accept() method */

static PyObject *
sock_accept(PySocketSockObject *s)
{
	sock_addr_t addrbuf;
	SOCKET_T newfd;
	socklen_t addrlen;
	PyObject *sock = NULL;
	PyObject *addr = NULL;
	PyObject *res = NULL;
	int timeout;

	if (!getsockaddrlen(s, &addrlen))
		return NULL;
	memset(&addrbuf, 0, addrlen);

#ifdef MS_WINDOWS
	newfd = INVALID_SOCKET;
#else
	newfd = -1;
#endif

	if (!IS_SELECTABLE(s))
		return select_error();

	Py_BEGIN_ALLOW_THREADS
	timeout = internal_select(s, 0);
	if (!timeout)
		newfd = accept(s->sock_fd, SAS2SA(&addrbuf), &addrlen);
	Py_END_ALLOW_THREADS

	if (timeout == 1) {
		PyErr_SetString(socket_timeout, "timed out");
		return NULL;
	}

#ifdef MS_WINDOWS
	if (newfd == INVALID_SOCKET)
#else
	if (newfd < 0)
#endif
		return s->errorhandler();

	/* Create the new object with unspecified family,
	   to avoid calls to bind() etc. on it. */
	sock = (PyObject *) new_sockobject(newfd,
					   s->sock_family,
					   s->sock_type,
					   s->sock_proto);

	if (sock == NULL) {
		SOCKETCLOSE(newfd);
		goto finally;
	}
	addr = makesockaddr(s->sock_fd, SAS2SA(&addrbuf),
			    addrlen, s->sock_proto);
	if (addr == NULL)
		goto finally;

	res = PyTuple_Pack(2, sock, addr);

finally:
	Py_XDECREF(sock);
	Py_XDECREF(addr);
	return res;
}

PyDoc_STRVAR(accept_doc,
"accept() -> (socket object, address info)\n\
\n\
Wait for an incoming connection.  Return a new socket representing the\n\
connection, and the address of the client.  For IP sockets, the address\n\
info is a pair (hostaddr, port).");

/* s.setblocking(flag) method.  Argument:
   False -- non-blocking mode; same as settimeout(0)
   True -- blocking mode; same as settimeout(None)
*/

static PyObject *
sock_setblocking(PySocketSockObject *s, PyObject *arg)
{
	int block;

	block = PyInt_AsLong(arg);
	if (block == -1 && PyErr_Occurred())
		return NULL;

	s->sock_timeout = block ? -1.0 : 0.0;
	internal_setblocking(s, block);

	Py_INCREF(Py_None);
	return Py_None;
}

PyDoc_STRVAR(setblocking_doc,
"setblocking(flag)\n\
\n\
Set the socket to blocking (flag is true) or non-blocking (false).\n\
setblocking(True) is equivalent to settimeout(None);\n\
setblocking(False) is equivalent to settimeout(0.0).");

/* s.settimeout(timeout) method.  Argument:
   None -- no timeout, blocking mode; same as setblocking(True)
   0.0  -- non-blocking mode; same as setblocking(False)
   > 0  -- timeout mode; operations time out after timeout seconds
   < 0  -- illegal; raises an exception
*/
static PyObject *
sock_settimeout(PySocketSockObject *s, PyObject *arg)
{
	double timeout;

	if (arg == Py_None)
		timeout = -1.0;
	else {
		timeout = PyFloat_AsDouble(arg);
		if (timeout < 0.0) {
			if (!PyErr_Occurred())
				PyErr_SetString(PyExc_ValueError,
						"Timeout value out of range");
			return NULL;
		}
	}

	s->sock_timeout = timeout;
	internal_setblocking(s, timeout < 0.0);

	Py_INCREF(Py_None);
	return Py_None;
}

PyDoc_STRVAR(settimeout_doc,
"settimeout(timeout)\n\
\n\
Set a timeout on socket operations.  'timeout' can be a float,\n\
giving in seconds, or None.  Setting a timeout of None disables\n\
the timeout feature and is equivalent to setblocking(1).\n\
Setting a timeout of zero is the same as setblocking(0).");

/* s.gettimeout() method.
   Returns the timeout associated with a socket. */
static PyObject *
sock_gettimeout(PySocketSockObject *s)
{
	if (s->sock_timeout < 0.0) {
		Py_INCREF(Py_None);
		return Py_None;
	}
	else
		return PyFloat_FromDouble(s->sock_timeout);
}

PyDoc_STRVAR(gettimeout_doc,
"gettimeout() -> timeout\n\
\n\
Returns the timeout in floating seconds associated with socket \n\
operations. A timeout of None indicates that timeouts on socket \n\
operations are disabled.");

#ifdef RISCOS
/* s.sleeptaskw(1 | 0) method */

static PyObject *
sock_sleeptaskw(PySocketSockObject *s,PyObject *arg)
{
	int block;
	block = PyInt_AsLong(arg);
	if (block == -1 && PyErr_Occurred())
		return NULL;
	Py_BEGIN_ALLOW_THREADS
	socketioctl(s->sock_fd, 0x80046679, (u_long*)&block);
	Py_END_ALLOW_THREADS

	Py_INCREF(Py_None);
	return Py_None;
}
PyDoc_STRVAR(sleeptaskw_doc,
"sleeptaskw(flag)\n\
\n\
Allow sleeps in taskwindows.");
#endif


/* s.setsockopt() method.
   With an integer third argument, sets an integer option.
   With a string third argument, sets an option from a buffer;
   use optional built-in module 'struct' to encode the string. */

static PyObject *
sock_setsockopt(PySocketSockObject *s, PyObject *args)
{
	int level;
	int optname;
	int res;
	char *buf;
	int buflen;
	int flag;

	if (PyArg_ParseTuple(args, "iii:setsockopt",
			     &level, &optname, &flag)) {
		buf = (char *) &flag;
		buflen = sizeof flag;
	}
	else {
		PyErr_Clear();
		if (!PyArg_ParseTuple(args, "iis#:setsockopt",
				      &level, &optname, &buf, &buflen))
			return NULL;
	}
	res = setsockopt(s->sock_fd, level, optname, (void *)buf, buflen);
	if (res < 0)
		return s->errorhandler();
	Py_INCREF(Py_None);
	return Py_None;
}

PyDoc_STRVAR(setsockopt_doc,
"setsockopt(level, option, value)\n\
\n\
Set a socket option.  See the Unix manual for level and option.\n\
The value argument can either be an integer or a string.");


/* s.getsockopt() method.
   With two arguments, retrieves an integer option.
   With a third integer argument, retrieves a string buffer of that size;
   use optional built-in module 'struct' to decode the string. */

static PyObject *
sock_getsockopt(PySocketSockObject *s, PyObject *args)
{
	int level;
	int optname;
	int res;
	PyObject *buf;
	socklen_t buflen = 0;

#ifdef __BEOS__
	/* We have incomplete socket support. */
	PyErr_SetString(socket_error, "getsockopt not supported");
	return NULL;
#else

	if (!PyArg_ParseTuple(args, "ii|i:getsockopt",
			      &level, &optname, &buflen))
		return NULL;

	if (buflen == 0) {
		int flag = 0;
		socklen_t flagsize = sizeof flag;
		res = getsockopt(s->sock_fd, level, optname,
				 (void *)&flag, &flagsize);
		if (res < 0)
			return s->errorhandler();
		return PyInt_FromLong(flag);
	}
#ifdef __VMS
	/* socklen_t is unsigned so no negative test is needed,
	   test buflen == 0 is previously done */
	if (buflen > 1024) {
#else
	if (buflen <= 0 || buflen > 1024) {
#endif
		PyErr_SetString(socket_error,
				"getsockopt buflen out of range");
		return NULL;
	}
	buf = PyString_FromStringAndSize((char *)NULL, buflen);
	if (buf == NULL)
		return NULL;
	res = getsockopt(s->sock_fd, level, optname,
			 (void *)PyString_AS_STRING(buf), &buflen);
	if (res < 0) {
		Py_DECREF(buf);
		return s->errorhandler();
	}
	_PyString_Resize(&buf, buflen);
	return buf;
#endif /* __BEOS__ */
}

PyDoc_STRVAR(getsockopt_doc,
"getsockopt(level, option[, buffersize]) -> value\n\
\n\
Get a socket option.  See the Unix manual for level and option.\n\
If a nonzero buffersize argument is given, the return value is a\n\
string of that length; otherwise it is an integer.");


/* s.bind(sockaddr) method */

static PyObject *
sock_bind(PySocketSockObject *s, PyObject *addro)
{
	sock_addr_t addrbuf;
	int addrlen;
	int res;

	if (!getsockaddrarg(s, addro, SAS2SA(&addrbuf), &addrlen))
		return NULL;
	Py_BEGIN_ALLOW_THREADS
	res = bind(s->sock_fd, SAS2SA(&addrbuf), addrlen);
	Py_END_ALLOW_THREADS
	if (res < 0)
		return s->errorhandler();
	Py_INCREF(Py_None);
	return Py_None;
}

PyDoc_STRVAR(bind_doc,
"bind(address)\n\
\n\
Bind the socket to a local address.  For IP sockets, the address is a\n\
pair (host, port); the host must refer to the local host. For raw packet\n\
sockets the address is a tuple (ifname, proto [,pkttype [,hatype]])");


/* s.close() method.
   Set the file descriptor to -1 so operations tried subsequently
   will surely fail. */

static PyObject *
sock_close(PySocketSockObject *s)
{
	SOCKET_T fd;

	if ((fd = s->sock_fd) != -1) {
		s->sock_fd = -1;
		Py_BEGIN_ALLOW_THREADS
		(void) SOCKETCLOSE(fd);
		Py_END_ALLOW_THREADS
	}
	Py_INCREF(Py_None);
	return Py_None;
}

PyDoc_STRVAR(close_doc,
"close()\n\
\n\
Close the socket.  It cannot be used after this call.");

static int
internal_connect(PySocketSockObject *s, struct sockaddr *addr, int addrlen,
		 int *timeoutp)
{
	int res, timeout;

	timeout = 0;
	res = connect(s->sock_fd, addr, addrlen);

#ifdef MS_WINDOWS

	if (s->sock_timeout > 0.0) {
		if (res < 0 && WSAGetLastError() == WSAEWOULDBLOCK &&
		    IS_SELECTABLE(s)) {
			/* This is a mess.  Best solution: trust select */
			fd_set fds;
			fd_set fds_exc;
			struct timeval tv;
			tv.tv_sec = (int)s->sock_timeout;
			tv.tv_usec = (int)((s->sock_timeout - tv.tv_sec) * 1e6);
			FD_ZERO(&fds);
			FD_SET(s->sock_fd, &fds);
			FD_ZERO(&fds_exc);
			FD_SET(s->sock_fd, &fds_exc);
			res = select(s->sock_fd+1, NULL, &fds, &fds_exc, &tv);
			if (res == 0) {
				res = WSAEWOULDBLOCK;
				timeout = 1;
			} else if (res > 0) {
				if (FD_ISSET(s->sock_fd, &fds))
					/* The socket is in the writeable set - this
					   means connected */
					res = 0;
				else {
					/* As per MS docs, we need to call getsockopt()
					   to get the underlying error */
					int res_size = sizeof res;
					/* It must be in the exception set */
					assert(FD_ISSET(s->sock_fd, &fds_exc));
					if (0 == getsockopt(s->sock_fd, SOL_SOCKET, SO_ERROR,
					                    (char *)&res, &res_size))
						/* getsockopt also clears WSAGetLastError,
						   so reset it back. */
						WSASetLastError(res);
					else
						res = WSAGetLastError();
				}
			}
			/* else if (res < 0) an error occurred */
		}
	}

	if (res < 0)
		res = WSAGetLastError();

#else

	if (s->sock_timeout > 0.0) {
		if (res < 0 && errno == EINPROGRESS && IS_SELECTABLE(s)) {
			timeout = internal_select(s, 1);
			if (timeout == 0) {
				res = connect(s->sock_fd, addr, addrlen);
				if (res < 0 && errno == EISCONN)
					res = 0;
			}
			else if (timeout == -1)
				res = errno;		/* had error */
			else
				res = EWOULDBLOCK;	/* timed out */
		}
	}

	if (r…