sysdeps/mach/hurd/ioctl.c

   1 /* Copyright (C) 1992, 1993, 1994 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 <ansidecl.h>
  20 #include <errno.h>
  21 #include <sys/ioctl.h>
  22 #include <hurd.h>
  23 #include <stdarg.h>
  24 #include <mach/notify.h>
  25
  26 /* Symbol set of ioctl handler lists.  If there are user-registered
  27    handlers, one of these lists will contain them.  The other lists are
  28    handlers built into the library.  */
  29 const struct
  30   {
  31     size_t n;
  32     struct ioctl_handler *v[0];
  33   } _hurd_ioctl_handler_lists;
  34
  35
  36 /* Perform the I/O control operation specified by REQUEST on FD.
  37    The actual type and use of ARG and the return value depend on REQUEST.  */
  38 int
  39 DEFUN(__ioctl, (fd, request),
  40       int fd AND unsigned long int request DOTS)
  41 {
  42   /* Map individual type fields to Mach IPC types.  */
  43   static const int mach_types[] =
  44     { MACH_MSG_TYPE_CHAR, MACH_MSG_TYPE_INTEGER_16, MACH_MSG_TYPE_INTEGER_32,
  45       -1 };
  46
  47   /* Message buffer.  */
  48   char msg[sizeof (mach_msg_header_t) + /* Header.  */
  49            sizeof (mach_msg_type_t) + 4 + /* Return code.  */
  50            3 * (sizeof (mach_msg_type_t) + (4 * 32))]; /* Argument data.  */
  51   mach_msg_header_t *m = (mach_msg_header_t *) msg;
  52   mach_msg_type_t *t = (mach_msg_type_t *) &m[1];
  53   mach_msg_id_t msgid;
  54
  55   void *arg;
  56
  57   union __ioctl r;
  58   error_t err;
  59
  60 #define io2mach_type(count, type) \
  61   ((mach_msg_type_t) { mach_types[type], (type << 1) * 8, count, 1, 0, 0 })
  62
  63   /* Pack an argument into the message buffer.  */
  64   inline void in (unsigned int count, unsigned int type)
  65     {
  66       if (count > 0)
  67         {
  68           void *const p = &t[1];
  69           const size_t len = count * (type << 1);
  70           *t = io2mach_type (count, type);
  71           memcpy (p, arg, len);
  72           arg += len;
  73           t = p + ((len + sizeof (*t) - 1) / sizeof (*t) * sizeof (*t));
  74         }
  75     }
  76
  77   /* Unpack the message buffer into the argument location.  */
  78   inline int out (unsigned int count, unsigned int type,
  79                   void *store, void **update)
  80     {
  81       if (count > 0)
  82         {
  83           const size_t len = count * (type << 1);
  84           union { mach_msg_type_t t; int i; } ipctype;
  85           ipctype.t = io2mach_type (count, type);
  86           if (*(int *) t != ipctype.i)
  87             return 1;
  88           ++t;
  89           memcpy (t, store, len);
  90           if (update != NULL)
  91             *update += len;
  92           t = (void *) t + ((len + sizeof (*t) - 1) / sizeof (*t) * sizeof *t);
  93         }
  94       return 0;
  95     }
  96
  97   va_list ap;
  98
  99   va_start (ap, request);
 100   arg = va_arg (ap, void *);
 101   va_end (ap);
 102
 103   {
 104     /* Check for a registered handler for REQUEST.  */
 105
 106     size_t i;
 107     const struct ioctl_handler *h;
 108
 109     for (i = 0; i < _hurd_ioctl_handler_lists.n; ++i)
 110       for (h = _hurd_ioctl_handler_lists.v[i]; h != NULL; h = h->next)
 111         if (request >= h->first_request && request <= h->last_request)
 112           /* This handler groks REQUEST.  Se lo puntamonos.  */
 113           return (*h->handler) (fd, request, arg);
 114   }
 115
 116
 117   /* Pack the argument data.  */
 118   r.__i = request;
 119
 120   msgid = 100000 + ((r.__s.group << 2) * 1000) + r.__s.command;
 121
 122   in (r.__t.count0, r.__t.type0);
 123   in (r.__t.count1, r.__t.type1);
 124   in (r.__t.count2, r.__t.type2);
 125
 126   err = _HURD_DPORT_USE
 127     (fd,
 128      ({
 129        m->msgh_size = (char *) t - msg;
 130        m->msgh_remote_port = port;
 131        m->msgh_local_port = __mig_reply_port ();
 132        m->msgh_seqno = 0;
 133        m->msgh_id = msgid;
 134 #if 0
 135        m->msgh_bits = ?;        /* XXX */
 136 #endif
 137        _HURD_EINTR_RPC (port, __mach_msg (m, MACH_SEND_MSG|MACH_RCV_MSG,
 138                                           m->msgh_size, sizeof (msg),
 139                                           m->msgh_reply_port,
 140                                           MACH_MSG_TIMEOUT_NONE,
 141                                           MACH_PORT_NULL));
 142      }));
 143
 144   switch (err)
 145     {
 146     case MACH_MSG_SUCCESS:
 147       break;
 148     case MACH_SEND_INVALID_REPLY:
 149     case MACH_RCV_INVALID_NAME:
 150       __mig_dealloc_reply_port ();
 151     default:
 152       return __hurd_fail (err);
 153     }
 154
 155   if (m->msgh_id != msgid + 100)
 156     return __hurd_fail (m->msgh_id == MACH_NOTIFY_SEND_ONCE ?
 157                         MIG_SERVER_DIED : MIG_REPLY_MISMATCH);
 158
 159   if ((m->msgh_bits & MACH_MSGH_BITS_COMPLEX) || /* XXX ? */
 160       m->msgh_size != (char *) t - msg)
 161     return __hurd_fail (MIG_TYPE_ERROR);
 162
 163   t = (mach_msg_type_t *) &m[1];
 164   if (out (1, _IOTS (sizeof (error_t)), &err, NULL) ||
 165       out (r.__t.count0, r.__t.type0, arg, &arg) ||
 166       out (r.__t.count1, r.__t.type2, arg, &arg) ||
 167       out (r.__t.count2, r.__t.type2, arg, &arg))
 168     return __hurd_fail (MIG_TYPE_ERROR);
 169
 170   if (err)
 171     return __hurd_fail (err);
 172   return 0;
 173 }