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Diffstat (limited to 'pthreads/src/pthread_cond_init.c')
| -rw-r--r-- | pthreads/src/pthread_cond_init.c | 167 |
1 files changed, 167 insertions, 0 deletions
diff --git a/pthreads/src/pthread_cond_init.c b/pthreads/src/pthread_cond_init.c new file mode 100644 index 0000000..f28fd67 --- /dev/null +++ b/pthreads/src/pthread_cond_init.c @@ -0,0 +1,167 @@ +/* + * 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 */ |