fhandler_socket.cc

cygwin, 著名的在win32下模拟unix操作系统的东东

	   stored address will be truncated."  We play it save here so
	   that the path always has a trailing 0 even if it's truncated. */
	strncpy (sun->sun_path, get_sun_path (),
		 *namelen - sizeof *sun + sizeof sun->sun_path - 1);

      *namelen = sizeof *sun - sizeof sun->sun_path
		 + strlen (sun->sun_path) + 1;
      res = 0;
    }
  else
    {
      res = ::getsockname (get_socket (), name, namelen);
      if (res)
	set_winsock_errno ();
    }

  return res;
}

int
fhandler_socket::getpeername (struct sockaddr *name, int *namelen)
{
  int res = ::getpeername (get_socket (), name, namelen);
  if (res)
    set_winsock_errno ();

  return res;
}

int
fhandler_socket::readv (const struct iovec *const iov, const int iovcnt,
			ssize_t tot)
{
  struct msghdr msg =
    {
      msg_name:		NULL,
      msg_namelen:	0,
      msg_iov:		(struct iovec *) iov, // const_cast
      msg_iovlen:	iovcnt,
      msg_accrights:	NULL,
      msg_accrightslen:	0
    };

  return recvmsg (&msg, 0, tot);
}

int
fhandler_socket::recvfrom (void *ptr, size_t len, int flags,
			   struct sockaddr *from, int *fromlen)
{
  int res;
  DWORD ret;

  flags &= MSG_WINMASK;
  if (!winsock2_active)
    ret = res = ::recvfrom (get_socket (),
			    (char *) ptr, len, flags,
			    from, fromlen);
  else
    {
      WSABUF wsabuf = { len, (char *) ptr };

      if (is_nonblocking ())
	res = WSARecvFrom (get_socket (), &wsabuf, 1, &ret, (DWORD *) &flags,
			   from, fromlen,
			   NULL, NULL);
      else
	{
	  wsock_event wsock_evt;
	  res = WSARecvFrom (get_socket (), &wsabuf, 1, &ret, (DWORD *) &flags,
			     from, fromlen,
			     wsock_evt.prepare (), NULL);

	  if (res == SOCKET_ERROR && WSAGetLastError () == WSA_IO_PENDING)
	    ret = res = wsock_evt.wait (get_socket (), (DWORD *) &flags);
	}
    }

  if (res == SOCKET_ERROR)
    {
      res = -1;
      set_winsock_errno ();
    }
  else
    res = ret;

  return res;
}

int
fhandler_socket::recvmsg (struct msghdr *msg, int flags, ssize_t tot)
{
  if (get_addr_family () == AF_LOCAL)
    {
      /* On AF_LOCAL sockets the (fixed-size) name of the shared memory
	 area used for descriptor passing is transmitted first.
	 If this string is empty, no descriptors are passed and we can
	 go ahead recv'ing the normal data blocks.  Otherwise start
	 special handling for descriptor passing. */
      /*TODO*/
    }

  struct iovec *const iov = msg->msg_iov;
  const int iovcnt = msg->msg_iovlen;

  struct sockaddr *from = (struct sockaddr *) msg->msg_name;
  int *fromlen = from ? &msg->msg_namelen : NULL;

  int res;

  if (!winsock2_active)
    {
      if (iovcnt == 1)
	res = recvfrom (iov->iov_base, iov->iov_len, flags,
			from, fromlen);
      else
	{
	  if (tot == -1)	// i.e. if not pre-calculated by the caller.
	    {
	      tot = 0;
	      const struct iovec *iovptr = iov + iovcnt;
	      do
		{
		  iovptr -= 1;
		  tot += iovptr->iov_len;
		}
	      while (iovptr != iov);
	    }

	  char *buf = (char *) alloca (tot);

	  if (!buf)
	    {
	      set_errno (ENOMEM);
	      res = -1;
	    }
	  else
	    {
	      res = recvfrom (buf, tot, flags,
			      from, fromlen);

	      const struct iovec *iovptr = iov;
	      int nbytes = res;

	      while (nbytes > 0)
		{
		  const int frag = min (nbytes, (ssize_t) iovptr->iov_len);
		  memcpy (iovptr->iov_base, buf, frag);
		  buf += frag;
		  iovptr += 1;
		  nbytes -= frag;
		}
	    }
	}
    }
  else
    {
      WSABUF wsabuf[iovcnt];

      {
	const struct iovec *iovptr = iov + iovcnt;
	WSABUF *wsaptr = wsabuf + iovcnt;
	do
	  {
	    iovptr -= 1;
	    wsaptr -= 1;
	    wsaptr->len = iovptr->iov_len;
	    wsaptr->buf = (char *) iovptr->iov_base;
	  }
	while (wsaptr != wsabuf);
      }

      DWORD ret;

      if (is_nonblocking ())
	res = WSARecvFrom (get_socket (),
			   wsabuf, iovcnt, &ret, (DWORD *) &flags,
			   from, fromlen,
			   NULL, NULL);
      else
	{
	  wsock_event wsock_evt;
	  res = WSARecvFrom (get_socket (),
			     wsabuf, iovcnt, &ret, (DWORD *) &flags,
			     from, fromlen,
			     wsock_evt.prepare (), NULL);

	  if (res == SOCKET_ERROR && WSAGetLastError () == WSA_IO_PENDING)
	    ret = res = wsock_evt.wait (get_socket (), (DWORD *) &flags);
	}

      if (res == SOCKET_ERROR)
	{
	  res = -1;
	  set_winsock_errno ();
	}
      else
	res = ret;
    }

  return res;
}

int
fhandler_socket::writev (const struct iovec *const iov, const int iovcnt,
			 ssize_t tot)
{
  struct msghdr msg =
    {
      msg_name:		NULL,
      msg_namelen:	0,
      msg_iov:		(struct iovec *) iov, // const_cast
      msg_iovlen:	iovcnt,
      msg_accrights:	NULL,
      msg_accrightslen:	0
    };

  return sendmsg (&msg, 0, tot);
}

int
fhandler_socket::sendto (const void *ptr, size_t len, int flags,
			 const struct sockaddr *to, int tolen)
{
  sockaddr_in sin;

  if (to && !get_inet_addr (to, tolen, &sin, &tolen))
    return -1;

  int res;
  DWORD ret;

  if (!winsock2_active)
    ret = res = ::sendto (get_socket (), (const char *) ptr, len,
			  flags & MSG_WINMASK,
			  (to ? (const struct sockaddr *) &sin : NULL), tolen);
  else
    {
      WSABUF wsabuf = { len, (char *) ptr };

      if (is_nonblocking ())
	res = WSASendTo (get_socket (), &wsabuf, 1, &ret,
			 flags & MSG_WINMASK,
			 (to ? (const struct sockaddr *) &sin : NULL), tolen,
			 NULL, NULL);
      else
	{
	  wsock_event wsock_evt;
	  res = WSASendTo (get_socket (), &wsabuf, 1, &ret,
			   flags & MSG_WINMASK,
			   (to ? (const struct sockaddr *) &sin : NULL), tolen,
			   wsock_evt.prepare (), NULL);

	  if (res == SOCKET_ERROR && WSAGetLastError () == WSA_IO_PENDING)
	    ret = res = wsock_evt.wait (get_socket (), (DWORD *) &flags);
	}
    }

  if (res == SOCKET_ERROR)
    {
      res = -1;
      set_winsock_errno ();
    }
  else
    res = ret;

  /* Special handling for SIGPIPE */
  if (res == -1 && get_errno () == ESHUTDOWN)
    {
      set_errno (EPIPE);
      if (! (flags & MSG_NOSIGNAL))
	raise (SIGPIPE);
    }

  return res;
}

int
fhandler_socket::sendmsg (const struct msghdr *msg, int flags, ssize_t tot)
{
  if (get_addr_family () == AF_LOCAL)
    {
      /* For AF_LOCAL/AF_UNIX sockets, if descriptors are given, start
	 the special handling for descriptor passing.  Otherwise just
	 transmit an empty string to tell the receiver that no
	 descriptor passing is done. */
      /*TODO*/
    }

  struct iovec *const iov = msg->msg_iov;
  const int iovcnt = msg->msg_iovlen;

  int res;

  if (!winsock2_active)
    {
      if (iovcnt == 1)
	res = sendto (iov->iov_base, iov->iov_len, flags,
		      (struct sockaddr *) msg->msg_name,
		      msg->msg_namelen);
      else
	{
	  if (tot == -1)	// i.e. if not pre-calculated by the caller.
	    {
	      tot = 0;
	      const struct iovec *iovptr = iov + iovcnt;
	      do
		{
		  iovptr -= 1;
		  tot += iovptr->iov_len;
		}
	      while (iovptr != iov);
	    }

	  char *const buf = (char *) alloca (tot);

	  if (!buf)
	    {
	      set_errno (ENOMEM);
	      res = -1;
	    }
	  else
	    {
	      char *bufptr = buf;
	      const struct iovec *iovptr = iov;
	      int nbytes = tot;

	      while (nbytes != 0)
		{
		  const int frag = min (nbytes, (ssize_t) iovptr->iov_len);
		  memcpy (bufptr, iovptr->iov_base, frag);
		  bufptr += frag;
		  iovptr += 1;
		  nbytes -= frag;
		}

	      res = sendto (buf, tot, flags,
			    (struct sockaddr *) msg->msg_name,
			    msg->msg_namelen);
	    }
	}
    }
  else
    {
      WSABUF wsabuf[iovcnt];

      {
	const struct iovec *iovptr = iov + iovcnt;
	WSABUF *wsaptr = wsabuf + iovcnt;
	do
	  {
	    iovptr -= 1;
	    wsaptr -= 1;
	    wsaptr->len = iovptr->iov_len;
	    wsaptr->buf = (char *) iovptr->iov_base;
	  }
	while (wsaptr != wsabuf);
      }

      DWORD ret;

      if (is_nonblocking ())
	res = WSASendTo (get_socket (), wsabuf, iovcnt, &ret, flags,
			 (struct sockaddr *) msg->msg_name,
			 msg->msg_namelen,
			 NULL, NULL);
      else
	{
	  wsock_event wsock_evt;
	  res = WSASendTo (get_socket (), wsabuf, iovcnt, &ret, flags,
			   (struct sockaddr *) msg->msg_name,
			   msg->msg_namelen,
			   wsock_evt.prepare (), NULL);

	  if (res == SOCKET_ERROR && WSAGetLastError () == WSA_IO_PENDING)
	    ret = res = wsock_evt.wait (get_socket (), (DWORD *) &flags);
	}

      if (res == SOCKET_ERROR)
	{
	  res = -1;
	  set_winsock_errno ();
	}
      else
	res = ret;
    }

  return res;
}

int
fhandler_socket::shutdown (int how)
{
  int res = ::shutdown (get_socket (), how);

  if (res)
    set_winsock_errno ();
  else
    switch (how)
      {
      case SHUT_RD:
	set_shutdown_read ();
	break;
      case SHUT_WR:
	set_shutdown_write ();
	break;
      case SHUT_RDWR:
	set_shutdown_read ();
	set_shutdown_write ();
	break;
      }
  return res;
}

int
fhandler_socket::close ()
{
  int res = 0;

  /* HACK to allow a graceful shutdown even if shutdown() hasn't been
     called by the application. Note that this isn't the ultimate
     solution but it helps in many cases. */
  struct linger linger;
  linger.l_onoff = 1;
  linger.l_linger = 240; /* seconds. default 2MSL value according to MSDN. */
  setsockopt (get_socket (), SOL_SOCKET, SO_LINGER,
	      (const char *)&linger, sizeof linger);

  while ((res = closesocket (get_socket ())) != 0)
    {
      if (WSAGetLastError () != WSAEWOULDBLOCK)
	{
	  set_winsock_errno ();
	  res = -1;
	  break;
	}
      if (WaitForSingleObject (signal_arrived, 10) == WAIT_OBJECT_0)
	{
	  set_errno (EINTR);
	  res = -1;
	  break;
	}
      WSASetLastError (0);
    }

  close_secret_event ();

  debug_printf ("%d = fhandler_socket::close()", res);
  return res;
}

#define ASYNC_MASK (FD_READ|FD_WRITE|FD_OOB|FD_ACCEPT|FD_CONNECT)

int
fhandler_socket::ioctl (unsigned int cmd, void *p)
{
  extern int get_ifconf (struct ifconf *ifc, int what); /* net.cc */
  int res;
  struct ifconf ifc, *ifcp;
  struct ifreq *ifr, *ifrp;

  switch (cmd)
    {
    case SIOCGIFCONF:
      ifcp = (struct ifconf *) p;
      if (!ifcp)
	{
	  set_errno (EINVAL);
	  return -1;
	}
      res = get_ifconf (ifcp, cmd);
      if (res)
	debug_printf ("error in get_ifconf");
      break;
    case SIOCGIFFLAGS:
      ifr = (struct ifreq *) p;
      if (ifr == 0)
	{
	  set_errno (EINVAL);
	  return -1;
	}
      ifr->ifr_flags = IFF_NOTRAILERS | IFF_UP | IFF_RUNNING;
      if (!strncmp(ifr->ifr_name, "lo", 2)
          || ntohl (((struct sockaddr_in *) &ifr->ifr_addr)->sin_addr.s_addr)
	  == INADDR_LOOPBACK)
	ifr->ifr_flags |= IFF_LOOPBACK;
      else
	ifr->ifr_flags |= IFF_BROADCAST;
      res = 0;
      break;
    case SIOCGIFBRDADDR:
    case SIOCGIFNETMASK:
    case SIOCGIFADDR:
    case SIOCGIFHWADDR:
    case SIOCGIFMETRIC:
    case SIOCGIFMTU:
      {
	ifc.ifc_len = 2048;
	ifc.ifc_buf = (char *) alloca (2048);

	ifr = (struct ifreq *) p;
	if (ifr == 0)
	  {
	    debug_printf ("ifr == NULL");
	    set_errno (EINVAL);
	    return -1;
	  }

	res = get_ifconf (&ifc, cmd);
	if (res)
	  {
	    debug_printf ("error in get_ifconf");
	    break;
	  }

	debug_printf ("    name: %s", ifr->ifr_name);
	for (ifrp = ifc.ifc_req;
	     (caddr_t) ifrp < ifc.ifc_buf + ifc.ifc_len;
	     ++ifrp)
	  {
	    debug_printf ("testname: %s", ifrp->ifr_name);
	    if (! strcmp (ifrp->ifr_name, ifr->ifr_name))
	      {
		switch (cmd)
		  {
		  case SIOCGIFADDR:
		    ifr->ifr_addr = ifrp->ifr_addr;
		    break;
		  case SIOCGIFBRDADDR:
		    ifr->ifr_broadaddr = ifrp->ifr_broadaddr;
		    break;
		  case SIOCGIFNETMASK:
		    ifr->ifr_netmask = ifrp->ifr_netmask;
		    break;
		  case SIOCGIFHWADDR:
		    ifr->ifr_hwaddr = ifrp->ifr_hwaddr;
		    break;
		  case SIOCGIFMETRIC:
		    ifr->ifr_metric = ifrp->ifr_metric;
		    break;
		  case SIOCGIFMTU:
		    ifr->ifr_mtu = ifrp->ifr_mtu;
		    break;
		  }
		break;
	      }
	  }
	if ((caddr_t) ifrp >= ifc.ifc_buf + ifc.ifc_len)
	  {
	    set_errno (EINVAL);
	    return -1;
	  }
	break;
      }
    case FIOASYNC:
      res = WSAAsyncSelect (get_socket (), gethwnd (), WM_ASYNCIO,
	      *(int *) p ? ASYNC_MASK : 0);
      syscall_printf ("Async I/O on socket %s",
	      *(int *) p ? "started" : "cancelled");
      set_async (*(int *) p);
      break;
    default:
      /* We must cancel WSAAsyncSelect (if any) before setting socket to
       * blocking mode
       */
      if (cmd == FIONBIO && *(int *) p == 0)
	WSAAsyncSelect (get_socket (), gethwnd (), 0, 0);
      res = ioctlsocket (get_socket (), cmd, (unsigned long *) p);
      if (res == SOCKET_ERROR)
	  set_winsock_errno ();
      if (cmd == FIONBIO)
	{
	  syscall_printf ("socket is now %sblocking",
			    *(int *) p ? "non" : "");
	  /* Start AsyncSelect if async socket unblocked */
	  if (*(int *) p && get_async ())
	    WSAAsyncSelect (get_socket (), gethwnd (), WM_ASYNCIO, ASYNC_MASK);

	  set_nonblocking (*(int *) p);
	}
      break;
    }
  syscall_printf ("%d = ioctl_socket (%x, %x)", res, cmd, p);
  return res;
}

int
fhandler_socket::fcntl (int cmd, void *arg)
{
  int res = 0;
  int request, current;

  switch (cmd)
    {
    case F_SETFL:
      {
	/* Carefully test for the O_NONBLOCK or deprecated OLD_O_NDELAY flag.
	   Set only the flag that has been passed in.  If both are set, just
	   record O_NONBLOCK.   */
	int new_flags = (int) arg & O_NONBLOCK_MASK;
	if ((new_flags & OLD_O_NDELAY) && (new_flags & O_NONBLOCK))
	  new_flags = O_NONBLOCK;
	current = get_flags () & O_NONBLOCK_MASK;
	request = new_flags ? 1 : 0;
	if (!!current != !!new_flags && (res = ioctl (FIONBIO, &request)))
	  break;
	set_flags ((get_flags () & ~O_NONBLOCK_MASK) | new_flags);
	break;
      }
    default:
      res = fhandler_base::fcntl (cmd, arg);
      break;
    }
  return res;
}

void
fhandler_socket::set_close_on_exec (int val)
{
  if (!winsock2_active) /* < Winsock 2.0 */
    set_inheritance (get_handle (), val);
  set_close_on_exec_flag (val);
  debug_printf ("set close_on_exec for %s to %d", get_name (), val);
}

void
fhandler_socket::set_sun_path (const char *path)
{
  sun_path = path ? cstrdup (path) : NULL;
}