hurd/hurdprio.c

   1 /* Support code for dealing with priorities in the Hurd.
   2    Copyright (C) 1994,95,96,97,99 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 Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the 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    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #include <hurd.h>
  21 #include <hurd/resource.h>
  22 #include <sys/mman.h>
  23 #include <unistd.h>
  24
  25 error_t
  26 _hurd_priority_which_map (enum __priority_which which, int who,
  27                           error_t (*function) (pid_t, struct procinfo *),
  28                           int pi_flags)
  29 {
  30   mach_msg_type_number_t npids = 64, i;
  31   pid_t pidbuf[npids], *pids = pidbuf;
  32   error_t err;
  33   struct procinfo *pip;
  34   int pibuf[sizeof *pip + 5 * sizeof (pip->threadinfos[0])], *pi = pibuf;
  35   mach_msg_type_number_t pisize = sizeof (pibuf) / sizeof (int);
  36
  37   switch (which)
  38     {
  39     default:
  40       return EINVAL;
  41
  42     case PRIO_PROCESS:
  43       err = (*function) (who ?: getpid (), 0); /* XXX special-case self? */
  44       break;
  45
  46     case PRIO_PGRP:
  47       err = __USEPORT (PROC, __proc_getpgrppids (port, who, &pids, &npids));
  48       for (i = 0; !err && i < npids; ++i)
  49         err = (*function) (pids[i], 0);
  50       break;
  51
  52     case PRIO_USER:
  53       if (who == 0)
  54         who = geteuid ();
  55       err = __USEPORT (PROC, __proc_getallpids (port, &pids, &npids));
  56       for (i = 0; !err && i < npids; ++i)
  57         {
  58           /* Get procinfo to check the owner.  */
  59           int *oldpi = pi;
  60           mach_msg_type_number_t oldpisize = pisize;
  61           char *tw = 0;
  62           size_t twsz = 0;
  63           err = __USEPORT (PROC, __proc_getprocinfo (port, pids[i],
  64                                                      &pi_flags,
  65                                                      &pi, &pisize,
  66                                                      &tw, &twsz));
  67           if (!err)
  68             {
  69               if (twsz)         /* Gratuitous.  */
  70                 __munmap (tw, twsz);
  71               if (pi != oldpi && oldpi != pibuf)
  72                 /* Old buffer from last call was not reused; free it.  */
  73                 __munmap (oldpi, oldpisize * sizeof pi[0]);
  74
  75               pip = (struct procinfo *) pi;
  76               if (pip->owner == (uid_t) who)
  77                 err = (*function) (pids[i], pip);
  78             }
  79         }
  80       break;
  81     }
  82
  83   if (pids != pidbuf)
  84     __munmap (pids, npids * sizeof pids[0]);
  85   if (pi != pibuf)
  86     __munmap (pi, pisize * sizeof pi[0]);
  87
  88   return err;
  89 }