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

   1 /* Copyright (C) 2011-2020 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Chris Metcalf <cmetcalf@tilera.com>, 2011.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library.  If not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 #include <sys/sendfile.h>
  20 #include <stddef.h>
  21 #include <errno.h>
  22 #include <sysdep.h>
  23
  24 /* Send COUNT bytes from file associated with IN_FD starting at OFFSET to
  25    descriptor OUT_FD.  */
  26 ssize_t
  27 sendfile (int out_fd, int in_fd, off_t *offset, size_t count)
  28 {
  29   __off64_t off64;
  30   int rc;
  31
  32   if (offset != NULL)
  33     {
  34       if (*offset < 0 || (off_t) (*offset + count) < 0)
  35         {
  36           __set_errno (EINVAL);
  37           return -1;
  38         }
  39       off64 = *offset;
  40     }
  41
  42   rc = INLINE_SYSCALL (sendfile64, 4, out_fd, in_fd,
  43                        offset ? &off64 : NULL, count);
  44   if (offset)
  45     *offset = off64;
  46   return rc;
  47 }