hurd/hurd/ioctl.h

   1 /* User-registered handlers for specific `ioctl' requests.
   2    Copyright (C) 1993-2015 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   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    <http://www.gnu.org/licenses/>.  */
  18
  19 #ifndef _HURD_IOCTL_H
  20 #define _HURD_IOCTL_H   1
  21
  22 #define __need___va_list
  23 #include <stdarg.h>
  24 #include <bits/ioctls.h>
  25
  26
  27 /* Type of handler function, called like ioctl to do its entire job.  */
  28 typedef int (*ioctl_handler_t) (int fd, int request, void *arg);
  29
  30 /* Structure that records an ioctl handler.  */
  31 struct ioctl_handler
  32   {
  33     /* Range of handled _IOC_NOTYPE (REQUEST) values.  */
  34     int first_request, last_request;
  35
  36     /* Handler function, called like ioctl to do its entire job.  */
  37     ioctl_handler_t handler;
  38
  39     struct ioctl_handler *next; /* Next handler.  */
  40   };
  41
  42
  43 /* Register HANDLER to handle ioctls with REQUEST values between
  44    FIRST_REQUEST and LAST_REQUEST inclusive.  Returns zero if successful.
  45    Return nonzero and sets `errno' for an error.  */
  46
  47 extern int hurd_register_ioctl_handler (int first_request, int last_request,
  48                                         ioctl_handler_t handler);
  49
  50
  51 /* Define a library-internal handler for ioctl commands between FIRST and
  52    LAST inclusive.  The last element gratuitously references HANDLER to
  53    avoid `defined but not used' warnings.  */
  54
  55 #define _HURD_HANDLE_IOCTLS_1(handler, first, last, moniker)                  \
  56   static const struct ioctl_handler handler##_ioctl_handler##moniker          \
  57         __attribute__ ((__unused__)) =                                        \
  58     { _IOC_NOTYPE (first), _IOC_NOTYPE (last),                                \
  59         (ioctl_handler_t) (handler), NULL };                                  \
  60   text_set_element (_hurd_ioctl_handler_lists,                                \
  61                     handler##_ioctl_handler##moniker)
  62 #define _HURD_HANDLE_IOCTLS(handler, first, last)                             \
  63   _HURD_HANDLE_IOCTLS_1 (handler, first, last, first##_to_##last)
  64
  65 /* Define a library-internal handler for a single ioctl command.  */
  66
  67 #define _HURD_HANDLE_IOCTL(handler, ioctl) \
  68   _HURD_HANDLE_IOCTLS_1 (handler, ioctl, ioctl, ioctl##_only)
  69
  70
  71 /* Lookup the handler for the given ioctl request.  */
  72
  73 ioctl_handler_t _hurd_lookup_ioctl_handler (int request);
  74
  75
  76 #endif  /* hurd/ioctl.h */