/* Try to Lock a mutex.  Generic version.   Copyright (C) 2002, 2005 Free Software Foundation, Inc.   This file is part of the GNU C Library.   The GNU C Library 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.   The GNU C Library 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 the GNU C Library; see the file COPYING.LIB.  If not,   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,   Boston, MA 02111-1307, USA.  */#include <pthread.h>#include <pt-internal.h>#define LOSE do { * (int *) 0 = 0; } while (1)/* Lock MUTEX, return EBUSY if we can't get it.  */int__pthread_mutex_trylock (struct __pthread_mutex *mutex){  int err;  struct __pthread *self;  __pthread_spin_lock (&mutex->__lock);  if (__pthread_spin_trylock (&mutex->__held) == 0)    /* Acquired the lock.  */    {      if (mutex->attr)	switch (mutex->attr->mutex_type)	  {	  case PTHREAD_MUTEX_NORMAL:	    break;	  case PTHREAD_MUTEX_RECURSIVE:	    mutex->locks = 1;	  case PTHREAD_MUTEX_ERRORCHECK:	    mutex->owner = _pthread_self ();	    break;	  default:	    LOSE;	  }      __pthread_spin_unlock (&mutex->__lock);      return 0;    }  err = EBUSY;  if (mutex->attr)    {      self = _pthread_self ();      switch (mutex->attr->mutex_type)	{	case PTHREAD_MUTEX_NORMAL:	  break;	case PTHREAD_MUTEX_ERRORCHECK:	  /* We could check if MUTEX->OWNER is SELF, however, POSIX	     does not permit pthread_mutex_trylock to return EDEADLK	     instead of EBUSY, only pthread_mutex_lock.  */	  break;	case PTHREAD_MUTEX_RECURSIVE:	  if (mutex->owner == self)	    {	      mutex->locks ++;	      err = 0;	    }	  break;	default:	  LOSE;	}    }  __pthread_spin_unlock (&mutex->__lock);  return err;}weak_alias (__pthread_mutex_trylock, _pthread_mutex_trylock);weak_alias (__pthread_mutex_trylock, pthread_mutex_trylock);