sysdeps/unix/sysv/linux/generic/wordsize-32/sendfile.c

   1 /* Copyright (C) 2011-2022 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library.  If not, see
  16    <https://www.gnu.org/licenses/>.  */
  17
  18 #include <sys/sendfile.h>
  19 #include <stddef.h>
  20 #include <errno.h>
  21 #include <sysdep.h>
  22
  23 /* Send COUNT bytes from file associated with IN_FD starting at OFFSET to
  24    descriptor OUT_FD.  */
  25 ssize_t
  26 sendfile (int out_fd, int in_fd, off_t *offset, size_t count)
  27 {
  28   __off64_t off64;
  29   int rc;
  30
  31   if (offset != NULL)
  32     {
  33       if (*offset < 0 || (off_t) (*offset + count) < 0)
  34         {
  35           __set_errno (EINVAL);
  36           return -1;
  37         }
  38       off64 = *offset;
  39     }
  40
  41   rc = INLINE_SYSCALL (sendfile64, 4, out_fd, in_fd,
  42                        offset ? &off64 : NULL, count);
  43   if (offset)
  44     *offset = off64;
  45   return rc;
  46 }