/* recvfrom.c --- wrappers for Windows recvfrom function

   Copyright (C) 2008-2020 Free Software Foundation, Inc.

   This program is free software: you can redistribute it and/or modify

   it under the terms of the GNU General Public License as published by

   the Free Software Foundation; either version 3 of the License, or

   (at your option) any later version.

   This program is distributed in the hope that it will be useful,

   but WITHOUT ANY WARRANTY; without even the implied warranty of

   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License

   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */

/* Written by Paolo Bonzini */

#include <config.h>

#define WIN32_LEAN_AND_MEAN

/* Get winsock2.h. */

#include <sys/socket.h>

/* Get set_winsock_errno, FD_TO_SOCKET etc. */

#include "w32sock.h"

#undef recvfrom

ssize_t

rpl_recvfrom (int fd, void *buf, size_t len, int flags, struct sockaddr *from,

              socklen_t *fromlen)

{

  SOCKET sock = FD_TO_SOCKET (fd);

  if (sock == INVALID_SOCKET)

    {

      errno = EBADF;

      return -1;

    }

  else

    {

      int frombufsize = (from != NULL ? *fromlen : 0);

      int r = recvfrom (sock, buf, len, flags, from, fromlen);

      if (r < 0)

        set_winsock_errno ();

      /* Winsock recvfrom() only returns a valid 'from' when the socket is

         connectionless.  POSIX gives a valid 'from' for all types of

         sockets.  */

      else if (from != NULL && *fromlen == frombufsize)

        rpl_getpeername (fd, from, fromlen);

      return r;

    }

}