sys/sem_open.c

   1 /*
   2  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
   7  *
   8  * This file contains Original Code and/or Modifications of Original Code
   9  * as defined in and that are subject to the Apple Public Source License
  10  * Version 2.0 (the 'License'). You may not use this file except in
  11  * compliance with the License. Please obtain a copy of the License at
  12  * http://www.opensource.apple.com/apsl/ and read it before using this
  13  * file.
  14  *
  15  * The Original Code and all software distributed under the License are
  16  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  17  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  18  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  20  * Please see the License for the specific language governing rights and
  21  * limitations under the License.
  22  *
  23  * @APPLE_LICENSE_HEADER_END@
  24  */
  25
  26 #ifdef __APPLE_PR3375657_HACK__
  27
  28 #include <stdio.h>
  29 #include <semaphore.h>
  30 #include <sys/syscall.h>
  31 #include <sys/types.h>
  32 #include <unistd.h>
  33 #include <alloca.h>
  34 #include <stdarg.h>
  35 #include <string.h>
  36
  37 __private_extern__ int _sem_match(const char *name);
  38
  39 sem_t *
  40 sem_open (const char *name, int flags, ...)
  41 {
  42         char            *buffer;
  43         va_list         ap;
  44         int             mode;
  45         unsigned int    value;
  46
  47         /*
  48         * To work-around applications that don't play
  49         * well in multiple GUI sessions, we append
  50         * shared memory names with the effective user ID.
  51         * It would be better to append the region name
  52         * with a session ID, but nothing like that
  53         * exists at this level of the system yet.
  54         */
  55
  56         if (_sem_match(name) && (buffer = alloca(strlen(name) + 32)) != NULL) {
  57                 sprintf(buffer, "%s\t%d", name, geteuid());
  58                 name = buffer;
  59         }
  60
  61 // sem_open (const char *name, int flags, mode_t mode, unsigned int value)
  62         va_start(ap, flags);
  63         mode = va_arg(ap, int); /* promoted from mode_t to int */
  64         value = va_arg(ap, unsigned int);
  65         va_end(ap);
  66
  67         return syscall (SYS_sem_open, name, flags, mode, value);
  68 }
  69
  70 #endif /* __APPLE_PR3375657_HACK__ */