| /* |
| * 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) |
| { |
| EnterCriticalSection (&ptw32_cond_list_lock); |
| |
| 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; |
| } |
| |
| LeaveCriticalSection (&ptw32_cond_list_lock); |
| } |
| |
| *cond = cv; |
| |
| return result; |
| |
| } /* pthread_cond_init */ |