124 lines
2.8 KiB
C
124 lines
2.8 KiB
C
|
/*
|
||
|
|
* pthread_spin_init.c
|
||
|
|
*
|
||
|
|
* Description:
|
||
|
|
* This translation unit implements spin lock 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_spin_init (pthread_spinlock_t * lock, int pshared)
|
||
|
|
{
|
||
|
|
pthread_spinlock_t s;
|
||
|
|
int cpus = 0;
|
||
|
|
int result = 0;
|
||
|
|
|
||
|
|
if (lock == NULL)
|
||
|
|
{
|
||
|
|
return EINVAL;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (0 != ptw32_getprocessors (&cpus))
|
||
|
|
{
|
||
|
|
cpus = 1;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (cpus > 1)
|
||
|
|
{
|
||
|
|
if (pshared == PTHREAD_PROCESS_SHARED)
|
||
|
|
{
|
||
|
|
/*
|
||
|
|
* Creating spinlock that can be shared between
|
||
|
|
* processes.
|
||
|
|
*/
|
||
|
|
#if _POSIX_THREAD_PROCESS_SHARED >= 0
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Not implemented yet.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#error ERROR [__FILE__, line __LINE__]: Process shared spin locks are not supported yet.
|
||
|
|
|
||
|
|
#else
|
||
|
|
|
||
|
|
return ENOSYS;
|
||
|
|
|
||
|
|
#endif /* _POSIX_THREAD_PROCESS_SHARED */
|
||
|
|
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
s = (pthread_spinlock_t) calloc (1, sizeof (*s));
|
||
|
|
|
||
|
|
if (s == NULL)
|
||
|
|
{
|
||
|
|
return ENOMEM;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (cpus > 1)
|
||
|
|
{
|
||
|
|
s->u.cpus = cpus;
|
||
|
|
s->interlock = PTW32_SPIN_UNLOCKED;
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
pthread_mutexattr_t ma;
|
||
|
|
result = pthread_mutexattr_init (&ma);
|
||
|
|
|
||
|
|
if (0 == result)
|
||
|
|
{
|
||
|
|
ma->pshared = pshared;
|
||
|
|
result = pthread_mutex_init (&(s->u.mutex), &ma);
|
||
|
|
if (0 == result)
|
||
|
|
{
|
||
|
|
s->interlock = PTW32_SPIN_USE_MUTEX;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
(void) pthread_mutexattr_destroy (&ma);
|
||
|
|
}
|
||
|
|
|
||
|
|
if (0 == result)
|
||
|
|
{
|
||
|
|
*lock = s;
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
(void) free (s);
|
||
|
|
*lock = NULL;
|
||
|
|
}
|
||
|
|
|
||
|
|
return (result);
|
||
|
|
}
|