sysdeps/generic/bp-semctl.h

   1 /* Bounded-pointer checking macros for C.
   2    Copyright (C) 2000 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Contributed by Greg McGary <greg@mcgary.org>
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Lesser General Public
   8    License as published by the Free Software Foundation; either
   9    version 2.1 of the License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public
  17    License along with the GNU C Library; if not, see
  18    <http://www.gnu.org/licenses/>.  */
  19
  20 #ifndef _bp_semctl_h_
  21 #define _bp_semctl_h_ 1
  22
  23 #if __BOUNDED_POINTERS__
  24
  25 # define CHECK_SEMCTL(ARGP, SEMID, CMD) check_semctl (ARGP, SEMID, CMD)
  26
  27 union semun *__unbounded
  28 check_semctl (union semun *arg, int semid, int cmd)
  29 {
  30   int ipc64 = (cmd & __IPC_64);
  31
  32   switch (cmd & ~__IPC_64)
  33     {
  34     case IPC_STAT:
  35     case IPC_SET:
  36       (void) CHECK_1 (arg->buf);
  37       break;
  38
  39     case GETALL:
  40     case SETALL:
  41       {
  42         struct semid_ds ds;
  43         union semun un = { .buf = &ds };
  44         unsigned int length = ~0;
  45
  46         /* It's unfortunate that we need to make a recursive
  47            system call to get the size of the semaphore set...  */
  48         if (semctl (semid, 0, IPC_STAT | ipc64, un) == 0)
  49           length = ds.sem_nsems;
  50         (void) CHECK_N (arg->array, length);
  51         break;
  52       }
  53
  54     case IPC_INFO:
  55       (void) CHECK_1 (arg->__buf);
  56       break;
  57     }
  58
  59   return __ptrvalue (arg);
  60 }
  61
  62 #else
  63 # define CHECK_SEMCTL(ARGP, SEMID, CMD) (ARGP)
  64 #endif
  65
  66 #endif /* _bp_semctl_h_ */