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/* Copyright (C) 2002 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
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, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <errno.h>
#include <stdlib.h>
#include <sysdep.h>
#include <sys/uio.h>
#include "pthreadP.h"
/* Not all versions of the kernel support extremely large numbers
of records. */
#ifndef UIO_FASTIOV
/* 1024 is what the kernels with NPTL support use. */
# define UIO_FASTIOV 1024
#endif
ssize_t
readv (fd, vector, count)
int fd;
const struct iovec *vector;
int count;
{
int oldtype = CANCEL_ASYNC ();
ssize_t result;
#ifdef INTERNAL_SYSCALL
result = INTERNAL_SYSCALL (readv, 3, fd, vector, count);
if (__builtin_expect (INTERNAL_SYSCALL_ERROR_P (result), 0))
{
if (count <= UIO_FASTIOV)
{
__set_errno (INTERNAL_SYSCALL_ERRNO (result));
result = -1;
}
else
result = __libc_readv (fd, vector, count);
}
#else
# if defined INLINE_SYSCALL
result = INLINE_SYSCALL (readv, 3, fd, vector, count);
if (result < 0 && errno == EINVAL
&& __builtin_expect (count > UIO_FASTIOV, 0))
# endif
result = __libc_readv (fd, vector, count);
#endif
CANCEL_RESET (oldtype);
return result;
}
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