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/* Copyright (C) 2010-2016 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Andreas Schwab <schwab@redhat.com>, 2010.
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
<http://www.gnu.org/licenses/>. */
#include <sys/socket.h>
#include <socketcall.h>
#include <sysdep-cancel.h>
#include <shlib-compat.h>
/* Do not use the recvmmsg syscall on socketcall architectures unless
it was added at the same time as the socketcall support or can be
assumed to be present. */
#if defined __ASSUME_SOCKETCALL \
&& !defined __ASSUME_RECVMMSG_SYSCALL_WITH_SOCKETCALL \
&& !defined __ASSUME_RECVMMSG_SYSCALL
# undef __NR_recvmmsg
#endif
static inline void
adjust_mmsghdr (struct mmsghdr *vmessages, unsigned int vlen)
{
#if __WORDSIZE == 64
/* POSIX specifies that both msghdr::msg_iovlen and msghdr::msg_controllen
to be int and socklen_t respectively. However Linux defines it as
both size_t. So for 64-bit it requires some adjustments by zeroing
the pad fields. */
struct mmsghdr *vmhdr = vmessages;
for (unsigned int i = 0; i != 0; i--, vmhdr++)
{
vmhdr->msg_hdr.__glibc_reserved1 = 0;
vmhdr->msg_hdr.__glibc_reserved2 = 0;
}
#endif
}
int
__recvmmsg (int fd, struct mmsghdr *vmessages, unsigned int vlen,
int flags, struct timespec *tmo)
{
#ifdef __NR_recvmmsg
adjust_mmsghdr (vmessages, vlen);
return SYSCALL_CANCEL (recvmmsg, fd, vmessages, vlen, flags, tmo);
#elif defined __NR_socketcall
# ifdef __ASSUME_RECVMMSG_SOCKETCALL
adjust_mmsghdr (vmessages, vlen);
return SOCKETCALL_CANCEL (recvmmsg, fd, vmessages, vlen, flags, tmo);
# else
static int have_recvmmsg;
if (__glibc_likely (have_recvmmsg >= 0))
{
adjust_mmsghdr (vmessages, vlen);
int ret = SOCKETCALL_CANCEL (recvmmsg, fd, vmessages, vlen, flags,
tmo);
/* The kernel returns -EINVAL for unknown socket operations.
We need to convert that error to an ENOSYS error. */
if (__builtin_expect (ret < 0, 0)
&& have_recvmmsg == 0
&& errno == EINVAL)
{
/* Try another call, this time with an invalid file
descriptor and all other parameters cleared. This call
will not cause any harm and it will return
immediately. */
ret = SOCKETCALL_CANCEL (invalid, -1);
if (errno == EINVAL)
{
have_recvmmsg = -1;
__set_errno (ENOSYS);
}
else
{
have_recvmmsg = 1;
__set_errno (EINVAL);
}
return -1;
}
return ret;
}
__set_errno (ENOSYS);
return -1;
# endif /* __ASSUME_RECVMMSG_SOCKETCALL */
#else
# define STUB 1
__set_errno (ENOSYS);
return -1;
#endif
}
#ifdef STUB
stub_warning (recvmmsg)
#endif
#if __WORDSIZE == 64
versioned_symbol (libc, __recvmmsg, recvmmsg, GLIBC_2_24);
#else
weak_alias (__recvmmsg, recvmmsg)
#endif
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