glibc/sysdeps/unix/sysv/linux/sendfile.c

56 lines
1.6 KiB
C

/* Transfer data between file descriptors. Linux version.
Copyright (C) 2011-2023 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 <sys/sendfile.h>
#include <stddef.h>
#include <errno.h>
#include <sysdep.h>
#ifndef __OFF_T_MATCHES_OFF64_T
/* Send COUNT bytes from file associated with IN_FD starting at OFFSET to
descriptor OUT_FD. */
ssize_t
sendfile (int out_fd, int in_fd, off_t *offset, size_t count)
{
# ifdef __NR_sendfile
return INLINE_SYSCALL_CALL (sendfile, out_fd, in_fd, offset, count);
# else
__off64_t off64;
int rc;
if (offset != NULL)
{
if (*offset < 0 || (off_t) (*offset + count) < 0)
{
__set_errno (EINVAL);
return -1;
}
off64 = *offset;
}
rc = INLINE_SYSCALL_CALL (sendfile64, out_fd, in_fd, offset ? &off64 : NULL,
count);
if (offset)
*offset = off64;
return rc;
# endif
}
#endif