libsyscall/wrappers/getiopolicy_np.c

   1 /*
   2  * Copyright (c) 2006 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 <errno.h>
  24 #include <sys/resource.h>
  25 #include <mach/port.h>
  26
  27 extern int __iopolicysys(int, struct _iopol_param_t *);
  28 extern void _pthread_clear_qos_tsd(mach_port_t);
  29
  30 int
  31 getiopolicy_np(int iotype, int scope)
  32 {
  33         int policy, error;
  34         struct _iopol_param_t iop_param;
  35
  36         /* Do not sanity check iotype and scope, leave it to kernel. */
  37
  38         iop_param.iop_scope = scope;
  39         iop_param.iop_iotype = iotype;
  40         error = __iopolicysys(IOPOL_CMD_GET, &iop_param);
  41         if (error != 0) {
  42                 errno = error;
  43                 policy = -1;
  44                 goto exit;
  45         }
  46
  47         policy = iop_param.iop_policy;
  48
  49 exit:
  50         return policy;
  51 }
  52
  53 int
  54 setiopolicy_np(int iotype, int scope, int policy)
  55 {
  56         /* kernel validates the indiv values, no need to repeat it */
  57         struct _iopol_param_t iop_param;
  58
  59         iop_param.iop_scope = scope;
  60         iop_param.iop_iotype = iotype;
  61         iop_param.iop_policy = policy;
  62
  63         int rv = __iopolicysys(IOPOL_CMD_SET, &iop_param);
  64         if (rv == -2) {
  65                 /* not an actual error but indication that __iopolicysys removed the thread QoS */
  66                 _pthread_clear_qos_tsd(MACH_PORT_NULL);
  67                 rv = 0;
  68         }
  69
  70         return rv;
  71 }