hurd/hurdprio.c

   1 /* Support code for dealing with priorities in the Hurd.
   2 Copyright (C) 1994 Free Software Foundation, Inc.
   3 This file is part of the GNU C Library.
   4
   5 The GNU C Library is free software; you can redistribute it and/or
   6 modify it under the terms of the GNU Library General Public License as
   7 published by the Free Software Foundation; either version 2 of the
   8 License, or (at your option) any later version.
   9
  10 The GNU C Library is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13 Library General Public License for more details.
  14
  15 You should have received a copy of the GNU Library General Public
  16 License along with the GNU C Library; see the file COPYING.LIB.  If
  17 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
  18 Cambridge, MA 02139, USA.  */
  19
  20 #include <hurd/resource.h>
  21 #include <hurd.h>
  22
  23 error_t
  24 _hurd_priority_which_map (enum __priority_which which, int who,
  25                           error_t (*function) (pid_t, struct procinfo *))
  26 {
  27   mach_msg_type_number_t npids = 64, i;
  28   pid_t pidbuf[npids], *pids;
  29   error_t err;
  30   struct procinfo *pip;
  31   int pibuf[sizeof *pip + 5 * sizeof (pip->threadinfos[0])], *pi = pibuf;
  32   mach_msg_type_number_t pisize = sizeof (pibuf) / sizeof (int);
  33
  34   switch (which)
  35     {
  36     case PRIO_PROCESS:
  37       npids = 1;
  38       pids[0] = who;
  39       err = 0;
  40       break;
  41
  42     case PRIO_PGRP:
  43       err = __USEPORT (PROC, __proc_getpgrppids (port, who, &pids, &npids));
  44       break;
  45
  46     case PRIO_USER:
  47       err = __USEPORT (PROC, __proc_getallpids (port, &pids, &npids));
  48       break;
  49
  50     default:
  51       return EINVAL;
  52     }
  53
  54   for (i = 0; !err && i < npids; ++i)
  55     {
  56       if (which == PRIO_USER)
  57         {
  58           /* Get procinfo to check the owner.  */
  59           int *oldpi = pi;
  60           mach_msg_type_number_t oldpisize = pisize;
  61           if (err = __USEPORT (PROC, __proc_getprocinfo (port, pids[i],
  62                                                          &pi, &pisize)))
  63             continue;
  64           if (pi != oldpi && oldpi != pibuf)
  65             /* Old buffer from last call was not reused; free it.  */
  66             __vm_deallocate (__mach_task_self (),
  67                              (vm_address_t) oldpi, oldpisize * sizeof pi[0]);
  68
  69           pip = (struct procinfo *) pi;
  70           if (pip->owner != (uid_t) who)
  71             continue;
  72         }
  73       else
  74         pip = NULL;
  75
  76       err = (*function) (pids[i], pip);
  77     }
  78
  79   if (pids != pidbuf)
  80     __vm_deallocate (__mach_task_self (),
  81                      (vm_address_t) pids, npids * sizeof pids[0]);
  82   if (pi != pibuf)
  83     __vm_deallocate (__mach_task_self (),
  84                      (vm_address_t) pi, pisize * sizeof pi[0]);
  85
  86   return err;
  87 }