1  /* pthread_mutex_consistent.  Hurd version.
       2     Copyright (C) 2016-2023 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, see
      17     <https://www.gnu.org/licenses/>.  */
      18  
      19  #include <pthread.h>
      20  #include <stdlib.h>
      21  #include <assert.h>
      22  #include <pt-internal.h>
      23  #include "pt-mutex.h"
      24  #include <hurdlock.h>
      25  
      26  int
      27  pthread_mutex_consistent (pthread_mutex_t *mtxp)
      28  {
      29    int ret = EINVAL;
      30    unsigned int val = mtxp->__lock;
      31  
      32    if ((mtxp->__flags & PTHREAD_MUTEX_ROBUST) != 0
      33        && (val & LLL_DEAD_OWNER) != 0
      34        && atomic_compare_and_exchange_bool_acq (&mtxp->__lock,
      35  					       __getpid () | LLL_WAITERS,
      36  					       val) == 0)
      37      {
      38        /* The mutex is now ours, and it's consistent. */
      39        mtxp->__owner_id = _pthread_self ()->thread;
      40        mtxp->__cnt = 1;
      41        ret = 0;
      42      }
      43  
      44    return ret;
      45  }
      46  
      47  weak_alias (pthread_mutex_consistent, pthread_mutex_consistent_np)