sys/semctl.c

   1 /*
   2  * Copyright (c) 2004 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23 #include <unistd.h>
  24 #include <stdarg.h>
  25 #include <sys/sem.h>
  26 #include <sys/syscall.h>
  27
  28 /*
  29  * Stub function to account for the differences in the ipc_perm structure,
  30  * while maintaining binary backward compatibility.
  31  */
  32 int
  33 semctl(int semid, int semnum, int cmd, ...)
  34 {
  35 #ifdef __DARWIN_UNIX03
  36         va_list                 ap;
  37         struct __semid_ds_new   *ds;
  38
  39         va_start(ap, cmd);
  40         ds = va_arg(ap, struct __semid_ds_new *);
  41         va_end(ap);
  42
  43         return syscall(SYS_semctl, semid, semnum, cmd, ds);
  44 #else   /* !__DARWIN_UNIX03 */
  45         va_list                 ap;
  46         struct __semid_ds_old   *ds_old;
  47         struct __semid_ds_new   ds;
  48         struct __semid_ds_new   *ds_new = &ds;
  49         int                     rv;
  50
  51         va_start(ap, cmd);
  52         ds_old = va_arg(ap, struct __semid_ds_old *);
  53         va_end(ap);
  54
  55 #define _UP_CVT(x)      ds_new-> x = ds_old-> x
  56 #define _DN_CVT(x)      ds_old-> x = ds_new-> x
  57
  58         if (cmd == IPC_SET) {
  59                 /* convert before call */
  60                 _UP_CVT(sem_perm.uid);
  61                 _UP_CVT(sem_perm.gid);
  62                 _UP_CVT(sem_perm.cuid);
  63                 _UP_CVT(sem_perm.cgid);
  64                 _UP_CVT(sem_perm.mode);
  65                 ds_new->sem_perm._seq = ds_old->sem_perm.seq;
  66                 ds_new->sem_perm._key = ds_old->sem_perm.key;
  67                 _UP_CVT(sem_base);
  68                 _UP_CVT(sem_nsems);
  69                 _UP_CVT(sem_otime);
  70                 _UP_CVT(sem_pad1);      /* binary compatibility */
  71                 _UP_CVT(sem_ctime);
  72                 _UP_CVT(sem_pad2);      /* binary compatibility */
  73                 _UP_CVT(sem_pad3[0]);   /* binary compatibility */
  74                 _UP_CVT(sem_pad3[1]);   /* binary compatibility */
  75                 _UP_CVT(sem_pad3[2]);   /* binary compatibility */
  76                 _UP_CVT(sem_pad3[3]);   /* binary compatibility */
  77         }
  78
  79         rv = syscall(SYS_semctl, semid, semnum, cmd, &ds);
  80
  81         if (cmd == IPC_STAT) {
  82                 /* convert after call */
  83                 _DN_CVT(sem_perm.uid);  /* warning!  precision loss! */
  84                 _DN_CVT(sem_perm.gid);  /* warning!  precision loss! */
  85                 _DN_CVT(sem_perm.cuid); /* warning!  precision loss! */
  86                 _DN_CVT(sem_perm.cgid); /* warning!  precision loss! */
  87                 _DN_CVT(sem_perm.mode);
  88                 ds_new->sem_perm.seq = ds_old->sem_perm._seq;
  89                 ds_new->sem_perm.key = ds_old->sem_perm._key;
  90                 _DN_CVT(sem_base);
  91                 _DN_CVT(sem_nsems);
  92                 _DN_CVT(sem_otime);
  93                 _DN_CVT(sem_pad1);      /* binary compatibility */
  94                 _DN_CVT(sem_ctime);
  95                 _DN_CVT(sem_pad2);      /* binary compatibility */
  96                 _DN_CVT(sem_pad3[0]);   /* binary compatibility */
  97                 _DN_CVT(sem_pad3[1]);   /* binary compatibility */
  98                 _DN_CVT(sem_pad3[2]);   /* binary compatibility */
  99                 _DN_CVT(sem_pad3[3]);   /* binary compatibility */
 100         }
 101
 102         return (rv);
 103 #endif  /* !__DARWIN_UNIX03 */
 104 }