/*
* pthread_cond_init.c
*
* Description:
* This translation unit implements condition variables and their primitives.
*
*
* --------------------------------------------------------------------------
*
* Pthreads-win32 - POSIX Threads Library for Win32
* Copyright(C) 1998 John E. Bossom
* Copyright(C) 1999,2005 Pthreads-win32 contributors
*
* Contact Email: rpj@callisto.canberra.edu.au
*
* The current list of contributors is contained
* in the file CONTRIBUTORS included with the source
* code distribution. The list can also be seen at the
* following World Wide Web location:
* http://sources.redhat.com/pthreads-win32/contributors.html
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library in 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 "implement.h"
int
pthread_cond_init (pthread_cond_t * cond, const pthread_condattr_t * attr)
/*
* ------------------------------------------------------
* DOCPUBLIC
* This function initializes a condition variable.
*
* PARAMETERS
* cond
* pointer to an instance of pthread_cond_t
*
* attr
* specifies optional creation attributes.
*
*
* DESCRIPTION
* This function initializes a condition variable.
*
* RESULTS
* 0 successfully created condition variable,
* EINVAL 'attr' is invalid,
* EAGAIN insufficient resources (other than
* memory,
* ENOMEM insufficient memory,
* EBUSY 'cond' is already initialized,
*
* ------------------------------------------------------
*/
{
int result;
pthread_cond_t cv = NULL;
if (cond == NULL)
{
return EINVAL;
}
if ((attr != NULL && *attr != NULL) &&
((*attr)->pshared == PTHREAD_PROCESS_SHARED))
{
/*
* Creating condition variable that can be shared between
* processes.
*/
result = ENOSYS;
goto DONE;
}
cv = (pthread_cond_t) calloc (1, sizeof (*cv));
if (cv == NULL)
{
result = ENOMEM;
goto DONE;
}
cv->nWaitersBlocked = 0;
cv->nWaitersToUnblock = 0;
cv->nWaitersGone = 0;
if (sem_init (&(cv->semBlockLock), 0, 1) != 0)
{
result = errno;
goto FAIL0;
}
if (sem_init (&(cv->semBlockQueue), 0, 0) != 0)
{
result = errno;
goto FAIL1;
}
if ((result = pthread_mutex_init (&(cv->mtxUnblockLock), 0)) != 0)
{
goto FAIL2;
}
result = 0;
goto DONE;
/*
* -------------
* Failed...
* -------------
*/
FAIL2:
(void) sem_destroy (&(cv->semBlockQueue));
FAIL1:
(void) sem_destroy (&(cv->semBlockLock));
FAIL0:
(void) free (cv);
cv = NULL;
DONE:
if (0 == result)
{
ptw32_mcs_local_node_t node;
ptw32_mcs_lock_acquire(&ptw32_cond_list_lock, &node);
cv->next = NULL;
cv->prev = ptw32_cond_list_tail;
if (ptw32_cond_list_tail != NULL)
{
ptw32_cond_list_tail->next = cv;
}
ptw32_cond_list_tail = cv;
if (ptw32_cond_list_head == NULL)
{
ptw32_cond_list_head = cv;
}
ptw32_mcs_lock_release(&node);
}
*cond = cv;
return result;
} /* pthread_cond_init */