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-rw-r--r--pthreads/pthread_spin_trylock.c80
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diff --git a/pthreads/pthread_spin_trylock.c b/pthreads/pthread_spin_trylock.c
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+/*
+ * pthread_spin_trylock.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_trylock (pthread_spinlock_t * lock)
+{
+ register pthread_spinlock_t s;
+
+ if (NULL == lock || NULL == *lock)
+ {
+ return (EINVAL);
+ }
+
+ if (*lock == PTHREAD_SPINLOCK_INITIALIZER)
+ {
+ int result;
+
+ if ((result = ptw32_spinlock_check_need_init (lock)) != 0)
+ {
+ return (result);
+ }
+ }
+
+ s = *lock;
+
+ switch ((long)
+ PTW32_INTERLOCKED_COMPARE_EXCHANGE ((PTW32_INTERLOCKED_LPLONG) &
+ (s->interlock),
+ (PTW32_INTERLOCKED_LONG)
+ PTW32_SPIN_LOCKED,
+ (PTW32_INTERLOCKED_LONG)
+ PTW32_SPIN_UNLOCKED))
+ {
+ case PTW32_SPIN_UNLOCKED:
+ return 0;
+ case PTW32_SPIN_LOCKED:
+ return EBUSY;
+ case PTW32_SPIN_USE_MUTEX:
+ return pthread_mutex_trylock (&(s->u.mutex));
+ }
+
+ return EINVAL;
+}