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/* Copyright (C) 2016 Free Software Foundation, Inc.
   Contributed by Agustina Arzille <avarzille@riseup.net>, 2016.

   This program is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public License
   as published by the Free Software Foundation; either
   version 2 of the license, or (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
   GNU Library General Public License for more details.

   You should have received a copy of the GNU Library General Public
   License along with this program; if not, see
   <http://www.gnu.org/licenses/>.
*/

#include <pthread.h>
#include <stdlib.h>
#include <assert.h>
#include <pt-internal.h>
#include "pt-mutex.h"
#include <hurdlock.h>

int __pthread_mutex_trylock (pthread_mutex_t *mtxp)
{
  struct __pthread *self;
  int ret;

  switch (MTX_TYPE (mtxp))
    {
      case PT_MTX_NORMAL:
        ret = lll_trylock (&mtxp->__lock);
        break;

      case PT_MTX_RECURSIVE:
        self = _pthread_self ();
        if (mtx_owned_p (mtxp, self, mtxp->__flags))
          {
            if (__glibc_unlikely (mtxp->__cnt + 1 == 0))
              return (EAGAIN);

            ++mtxp->__cnt;
            ret = 0;
          }
        else if ((ret = lll_trylock (&mtxp->__lock)) == 0)
          {
            mtx_set_owner (mtxp, self, mtxp->__flags);
            mtxp->__cnt = 1;
          }

        break;

      case PT_MTX_ERRORCHECK:
        self = _pthread_self ();
        if ((ret = lll_trylock (&mtxp->__lock)) == 0)
          mtx_set_owner (mtxp, self, mtxp->__flags);
        break;

      case PT_MTX_NORMAL     | PTHREAD_MUTEX_ROBUST:
      case PT_MTX_RECURSIVE  | PTHREAD_MUTEX_ROBUST:
      case PT_MTX_ERRORCHECK | PTHREAD_MUTEX_ROBUST:
        self = _pthread_self ();
        ROBUST_LOCK (self, mtxp, __lll_robust_trylock);
        break;

      default:
        ret = EINVAL;
        break;
    }

  return (ret);
}

strong_alias (__pthread_mutex_trylock, _pthread_mutex_trylock)
strong_alias (__pthread_mutex_trylock, pthread_mutex_trylock)