lib/recvfrom.c

   1 /* recvfrom.c --- wrappers for Windows recvfrom function
   2
   3    Copyright (C) 2008-2024 Free Software Foundation, Inc.
   4
   5    This file is free software: you can redistribute it and/or modify
   6    it under the terms of the GNU Lesser General Public License as
   7    published by the Free Software Foundation; either version 2.1 of the
   8    License, or (at your option) any later version.
   9
  10    This file is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13    GNU Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public License
  16    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  17
  18 /* Written by Paolo Bonzini */
  19
  20 #include <config.h>
  21
  22 #define WIN32_LEAN_AND_MEAN
  23 /* Get winsock2.h. */
  24 #include <sys/socket.h>
  25
  26 /* Get set_winsock_errno, FD_TO_SOCKET etc. */
  27 #include "w32sock.h"
  28
  29 #undef recvfrom
  30
  31 ssize_t
  32 rpl_recvfrom (int fd, void *buf, size_t len, int flags, struct sockaddr *from,
  33               socklen_t *fromlen)
  34 {
  35   SOCKET sock = FD_TO_SOCKET (fd);
  36
  37   if (sock == INVALID_SOCKET)
  38     {
  39       errno = EBADF;
  40       return -1;
  41     }
  42   else
  43     {
  44       int frombufsize = (from != NULL ? *fromlen : 0);
  45       int r = recvfrom (sock, buf, len, flags, from, fromlen);
  46
  47       if (r < 0)
  48         set_winsock_errno ();
  49
  50       /* Winsock recvfrom() only returns a valid 'from' when the socket is
  51          connectionless.  POSIX gives a valid 'from' for all types of
  52          sockets.  */
  53       else if (from != NULL && *fromlen == frombufsize)
  54         rpl_getpeername (fd, from, fromlen);
  55
  56       return r;
  57     }
  58 }