diff options
author | rpj <rpj> | 2002-02-18 03:16:52 +0000 |
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committer | rpj <rpj> | 2002-02-18 03:16:52 +0000 |
commit | a416ab17ecf9f2cb0f1e3f7bd645a8d1ce690ca2 (patch) | |
tree | 72f776cd64e48824a5578ff7a523bc69097143b4 /pthread_spin_lock.c | |
parent | e6f1797e9e9925ae7f9dda54806ef8f52ae3ed07 (diff) |
Major reorganisation of source code; new routine and tests added.
Diffstat (limited to 'pthread_spin_lock.c')
-rw-r--r-- | pthread_spin_lock.c | 77 |
1 files changed, 77 insertions, 0 deletions
diff --git a/pthread_spin_lock.c b/pthread_spin_lock.c new file mode 100644 index 0000000..d3355d1 --- /dev/null +++ b/pthread_spin_lock.c @@ -0,0 +1,77 @@ +/* + * pthread_spin_lock.c + * + * Description: + * This translation unit implements spin lock primitives. + * + * -------------------------------------------------------------------------- + * + * Pthreads-win32 - POSIX Threads Library for Win32 + * Copyright(C) 1998 John E. Bossom + * Copyright(C) 1999,2002 Pthreads-win32 contributors + * + * Contact Email: rpj@ise.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" + + +/* + * NOTE: For speed, these routines don't check if "lock" is valid. + */ +int +pthread_spin_lock(pthread_spinlock_t *lock) +{ + register pthread_spinlock_t s; + + if (*lock == PTHREAD_SPINLOCK_INITIALIZER) + { + int result; + + if ((result = ptw32_spinlock_check_need_init(lock)) != 0) + { + return(result); + } + } + + s = *lock; + + while ( (PTW32_INTERLOCKED_LONG) PTW32_SPIN_LOCKED == + ptw32_interlocked_compare_exchange((PTW32_INTERLOCKED_LPLONG) &(s->interlock), + (PTW32_INTERLOCKED_LONG) PTW32_SPIN_LOCKED, + (PTW32_INTERLOCKED_LONG) PTW32_SPIN_UNLOCKED) ) + {} + + if (s->interlock == PTW32_SPIN_LOCKED) + { + return 0; + } + else if (s->interlock == PTW32_SPIN_USE_MUTEX) + { + return pthread_mutex_lock(&(s->u.mutex)); + } + + return EINVAL; +} |