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/* Copyright (C) 1999-2021 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#include <stdio.h>
#include <sys/socket.h>
#include <libc-lock.h>
/* Return a socket of any type. The socket can be used in subsequent
ioctl calls to talk to the kernel. */
int
__opensock (void)
{
/* Cache the last AF that worked, to avoid many redundant calls to
socket(). */
static int sock_af = -1;
int fd = -1;
__libc_lock_define_initialized (static, lock);
if (sock_af != -1)
{
fd = __socket (sock_af, SOCK_DGRAM, 0);
if (fd != -1)
return fd;
}
__libc_lock_lock (lock);
if (sock_af != -1)
fd = __socket (sock_af, SOCK_DGRAM, 0);
if (fd == -1)
{
#ifdef AF_INET
fd = __socket (sock_af = AF_INET, SOCK_DGRAM, 0);
#endif
#ifdef AF_INET6
if (fd < 0)
fd = __socket (sock_af = AF_INET6, SOCK_DGRAM, 0);
#endif
#ifdef AF_IPX
if (fd < 0)
fd = __socket (sock_af = AF_IPX, SOCK_DGRAM, 0);
#endif
#ifdef AF_AX25
if (fd < 0)
fd = __socket (sock_af = AF_AX25, SOCK_DGRAM, 0);
#endif
#ifdef AF_APPLETALK
if (fd < 0)
fd = __socket (sock_af = AF_APPLETALK, SOCK_DGRAM, 0);
#endif
}
__libc_lock_unlock (lock);
return fd;
}
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