aboutsummaryrefslogtreecommitdiff
path: root/sysdeps/mach/hurd/ioctl.c
blob: 5c6138fc0b0a8642b9bec037736ff861d3fd3719 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
/* Copyright (C) 1992,93,94,95,96,97,99,2000 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public License as
   published by the Free Software Foundation; either version 2 of the
   License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public
   License along with the GNU C Library; see the file COPYING.LIB.  If not,
   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

#include <errno.h>
#include <sys/ioctl.h>
#include <hurd.h>
#include <hurd/fd.h>
#include <hurd/signal.h>
#include <stdarg.h>
#include <mach/notify.h>
#include <assert.h>
#include <string.h>
#include <stdint.h>
#include <hurd/ioctl.h>
#include <mach/mig_support.h>

#include <hurd/ioctls.defs>

#define typesize(type)	(1 << (type))


/* Perform the I/O control operation specified by REQUEST on FD.
   The actual type and use of ARG and the return value depend on REQUEST.  */
int
__ioctl (int fd, unsigned long int request, ...)
{
  /* Map individual type fields to Mach IPC types.  */
  static const int mach_types[] =
    { MACH_MSG_TYPE_CHAR, MACH_MSG_TYPE_INTEGER_16, MACH_MSG_TYPE_INTEGER_32,
      MACH_MSG_TYPE_INTEGER_64 };
#define io2mach_type(count, type) \
  ((mach_msg_type_t) { mach_types[type], typesize (type) * 8, count, 1, 0, 0 })

  /* Extract the type information encoded in the request.  */
  unsigned int type = _IOC_TYPE (request);

  /* Message buffer.  */
#define msg_align(x) \
  (((x) + sizeof (mach_msg_type_t) - 1) & ~(sizeof (mach_msg_type_t) - 1))
  struct
    {
      mig_reply_header_t header;
      char data[3 * sizeof (mach_msg_type_t) +
		msg_align (_IOT_COUNT0 (type) * typesize (_IOT_TYPE0 (type))) +
		msg_align (_IOT_COUNT1 (type) * typesize (_IOT_TYPE1 (type))) +
		_IOT_COUNT2 (type) * typesize (_IOT_TYPE2 (type))];
    } msg;
  mach_msg_header_t *const m = &msg.header.Head;
  mach_msg_type_t *t;
  mach_msg_id_t msgid;
  unsigned int reply_size;

  void *arg;

  error_t err;

  /* Send the RPC already packed up in MSG to IOPORT
     and decode the return value.  */
  error_t send_rpc (io_t ioport)
    {
      error_t err;
      mach_msg_type_t *t = &msg.header.RetCodeType;

      /* Marshal the request arguments into the message buffer.
	 We must redo this work each time we retry the RPC after a SIGTTOU,
	 because the reply message containing the EBACKGROUND error code
	 clobbers the same message buffer also used for the request.  */

      if (_IOC_INOUT (request) & IOC_IN)
	{
	  /* We don't want to advance ARG since it will be used to copy out
             too if IOC_OUT is also set.  */
	  void *argptr = arg;

	  /* Pack an argument into the message buffer.  */
	  void in (unsigned int count, enum __ioctl_datum type)
	    {
	      if (count > 0)
		{
		  void *p = &t[1];
		  const size_t len = count * typesize ((unsigned int) type);
		  *t = io2mach_type (count, type);
		  p = __mempcpy (p, argptr, len);
		  argptr += len;
		  p = (void *) (((uintptr_t) p + sizeof (*t) - 1)
				& ~(sizeof (*t) - 1));
		  t = p;
		}
	    }

	  /* Pack the argument data.  */
	  in (_IOT_COUNT0 (type), _IOT_TYPE0 (type));
	  in (_IOT_COUNT1 (type), _IOT_TYPE1 (type));
	  in (_IOT_COUNT2 (type), _IOT_TYPE2 (type));
	}
      else if (_IOC_INOUT (request) == IOC_VOID)
	{
	  /* The RPC takes a single integer_t argument.
	     Rather than pointing to the value, ARG is the value itself.  */
	  *t++ = io2mach_type (1, _IOTS (int));
	  *((int *) t)++ = (int) arg;
	}

      m->msgh_size = (char *) t - (char *) &msg;
      m->msgh_remote_port = ioport;
      m->msgh_local_port = __mig_get_reply_port ();
      m->msgh_seqno = 0;
      m->msgh_id = msgid;
      m->msgh_bits = MACH_MSGH_BITS (MACH_MSG_TYPE_COPY_SEND,
				     MACH_MSG_TYPE_MAKE_SEND_ONCE);
      err = _hurd_intr_rpc_mach_msg (m, MACH_SEND_MSG|MACH_RCV_MSG,
				     m->msgh_size, sizeof (msg),
				     m->msgh_local_port,
				     MACH_MSG_TIMEOUT_NONE,
				     MACH_PORT_NULL);
      switch (err)
	{
	case MACH_MSG_SUCCESS:
	  break;
	case MACH_SEND_INVALID_REPLY:
	case MACH_RCV_INVALID_NAME:
	  __mig_dealloc_reply_port (m->msgh_local_port);
	default:
	  return err;
	}

      if ((m->msgh_bits & MACH_MSGH_BITS_COMPLEX))
	{
	  /* Allow no ports or VM.  */
	  __mach_msg_destroy (m);
	  /* Want to return a different error below for a different msgid.  */
	  if (m->msgh_id == msgid + 100)
	    return MIG_TYPE_ERROR;
	}

      if (m->msgh_id != msgid + 100)
	return (m->msgh_id == MACH_NOTIFY_SEND_ONCE ?
		MIG_SERVER_DIED : MIG_REPLY_MISMATCH);

      if (m->msgh_size != reply_size &&
	  m->msgh_size != sizeof (mig_reply_header_t))
	return MIG_TYPE_ERROR;

      if (*(int *) &msg.header.RetCodeType !=
	  ((union { mach_msg_type_t t; int i; })
	   { t: io2mach_type (1, _IOTS (sizeof msg.header.RetCode)) }).i)
	return MIG_TYPE_ERROR;
      return msg.header.RetCode;
    }

  va_list ap;

  va_start (ap, request);
  arg = va_arg (ap, void *);
  va_end (ap);

  {
    /* Check for a registered handler for REQUEST.  */
    ioctl_handler_t handler = _hurd_lookup_ioctl_handler (request);
    if (handler)
      {
	/* This handler groks REQUEST.  Se lo puntamonos.  */
	int save = errno;
	int result = (*handler) (fd, request, arg);
	if (result != -1 || errno != ENOTTY)
	  return result;

	/* The handler doesn't really grok this one.
	   Try the normal RPC translation.  */
	errno = save;
      }
  }

  /* Compute the Mach message ID for the RPC from the group and command
     parts of the ioctl request.  */
  msgid = IOC_MSGID (request);

  /* Compute the expected size of the reply.  There is a standard header
     consisting of the message header and the reply code.  Then, for out
     and in/out ioctls, there come the data with their type headers.  */
  reply_size = sizeof (mig_reply_header_t);

  if (_IOC_INOUT (request) & IOC_OUT)
    {
      inline void figure_reply (unsigned int count, enum __ioctl_datum type)
	{
	  if (count > 0)
	    {
	      /* Add the size of the type and data.  */
	      reply_size += sizeof (mach_msg_type_t) + typesize (type) * count;
	      /* Align it to word size.  */
	      reply_size += sizeof (mach_msg_type_t) - 1;
	      reply_size &= ~(sizeof (mach_msg_type_t) - 1);
	    }
	}
      figure_reply (_IOT_COUNT0 (type), _IOT_TYPE0 (type));
      figure_reply (_IOT_COUNT1 (type), _IOT_TYPE1 (type));
      figure_reply (_IOT_COUNT2 (type), _IOT_TYPE2 (type));
    }

  /* Marshal the arguments into the request message and make the RPC.
     This wrapper function handles EBACKGROUND returns, turning them
     into either SIGTTOU or EIO.  */
  err = HURD_DPORT_USE (fd, _hurd_ctty_output (port, ctty, send_rpc));

  t = (mach_msg_type_t *) msg.data;
  switch (err)
    {
      /* Unpack the message buffer into the argument location.  */
      int out (unsigned int count, unsigned int type,
	       void *store, void **update)
	{
	  if (count > 0)
	    {
	      const size_t len = count * typesize (type);
	      union { mach_msg_type_t t; int i; } ipctype;
	      ipctype.t = io2mach_type (count, type);
	      if (*(int *) t != ipctype.i)
		return 1;
	      ++t;
	      memcpy (store, t, len);
	      if (update != NULL)
		*update += len;
	      t = (void *) (((uintptr_t) t + len + sizeof (*t) - 1)
			    & ~(sizeof (*t) - 1));
	    }
	  return 0;
	}

    case 0:
      if (m->msgh_size != reply_size ||
	  ((_IOC_INOUT (request) & IOC_OUT) &&
	   (out (_IOT_COUNT0 (type), _IOT_TYPE0 (type), arg, &arg) ||
	    out (_IOT_COUNT1 (type), _IOT_TYPE1 (type), arg, &arg) ||
	    out (_IOT_COUNT2 (type), _IOT_TYPE2 (type), arg, &arg))))
	return __hurd_fail (MIG_TYPE_ERROR);
      return 0;

    case MIG_BAD_ID:
    case EOPNOTSUPP:
      /* The server didn't understand the RPC.  */
      err = ENOTTY;
    default:
      return __hurd_fail (err);
    }
}

weak_alias (__ioctl, ioctl)