hurd/fd-read.c

   1 /* Copyright (C) 1993, 1994, 1995 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 Library General Public License as
   6 published by the Free Software Foundation; either version 2 of the
   7 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 Library General Public License for more details.
  13
  14 You should have received a copy of the GNU Library General Public
  15 License along with the GNU C Library; see the file COPYING.LIB.  If
  16 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
  17 Cambridge, MA 02139, USA.  */
  18
  19 #include <errno.h>
  20 #include <unistd.h>
  21 #include <hurd.h>
  22 #include <hurd/fd.h>
  23 #include <string.h>
  24
  25 error_t
  26 _hurd_fd_read (struct hurd_fd *fd, void *buf, size_t *nbytes)
  27 {
  28   error_t err;
  29   char *data;
  30   mach_msg_type_number_t nread;
  31
  32   error_t readfd (io_t port)
  33     {
  34       return __io_read (port, &data, &nread, -1, *nbytes);
  35     }
  36
  37   data = buf;
  38   if (err = HURD_FD_PORT_USE (fd, _hurd_ctty_input (port, ctty, readfd)))
  39     return err;
  40
  41   if (data != buf)
  42     {
  43       memcpy (buf, data, nread);
  44       __vm_deallocate (__mach_task_self (), (vm_address_t) data, nread);
  45     }
  46
  47   *nbytes = nread;
  48   return 0;
  49 }