add plibsys

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diff --git a/3rdparty/plibsys/src/pspinlock.h b/3rdparty/plibsys/src/pspinlock.h
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+++ b/3rdparty/plibsys/src/pspinlock.h
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+/*
+ * The MIT License
+ *
+ * Copyright (C) 2016 Alexander Saprykin <saprykin.spb@gmail.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * 'Software'), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+ * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+ * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+/**
+ * @file pspinlock.h
+ * @brief Light-weight atomic spinlock
+ * @author Alexander Saprykin
+ *
+ * A spinlock is an inter-thread synchronization primitive based on atomic
+ * operations. It allows to guard a critical section from concurrent access of
+ * multiple threads at once. It is very similar to a mutex in semantics, but
+ * inside it provides a more light-weight and fast locking mechanism without
+ * thread sleeping and undesirable context switching. Thus spinlocks should be
+ * used only for small code sections, otherwise long-time spinning can cause
+ * extensive CPU time waste by waiting threads.
+ *
+ * As the spinlock is based on atomic operations it would have the real meaning
+ * only if an underlying atomic model is lock-free (not simulated using the
+ * mutex). You can check if the atomic model is lock-free with
+ * p_atomic_is_lock_free(). Otherwise usage of spinlocks will be the same as the
+ * ordinary mutex.
+ *
+ * To create a new spinlock primitive the p_spinlock_new() routine should be
+ * called, to delete the unused spinlock primitive use p_spinlock_free().
+ *
+ * Use p_spinlock_lock() or p_spinlock_trylock() to synchronize access at the
+ * beginning of the critical section. Only the one thread is allowed to pass
+ * this call, others will wait for the p_spinlock_unlock() call which marks the
+ * end of the critical section. This way the critical section code is guarded
+ * against concurrent access of multiple threads at once.
+ */
+
+#if !defined (PLIBSYS_H_INSIDE) && !defined (PLIBSYS_COMPILATION)
+#  error "Header files shouldn't be included directly, consider using <plibsys.h> instead."
+#endif
+
+#ifndef PLIBSYS_HEADER_PSPINLOCK_H
+#define PLIBSYS_HEADER_PSPINLOCK_H
+
+#include <pmacros.h>
+#include <ptypes.h>
+
+P_BEGIN_DECLS
+
+/** Spinlock opaque data structure. */
+typedef struct PSpinLock_ PSpinLock;
+
+/**
+ * @brief Creates a new #PSpinLock object.
+ * @return Pointer to a newly created #PSpinLock object.
+ * @since 0.0.1
+ */
+P_LIB_API PSpinLock *	p_spinlock_new		(void);
+
+/**
+ * @brief Locks a spinlock.
+ * @param spinlock #PSpinLock to lock.
+ * @return TRUE in case of success, FALSE otherwise.
+ * @since 0.0.1
+ *
+ * A thread will not sleep in this call if another thread is holding the lock,
+ * instead it will try to lock @a spinlock in an infinite loop.
+ *
+ * If the atomic model is not lock-free this call will have the same effect
+ * as p_mutex_lock().
+ *
+ * Do not lock a spinlock recursively - this may lead to an application
+ * deadlock.
+ */
+P_LIB_API pboolean	p_spinlock_lock		(PSpinLock *spinlock);
+
+/**
+ * @brief Tries to lock a spinlock immediately.
+ * @param spinlock #PSpinLock to lock.
+ * @return TRUE in case of success, FALSE otherwise.
+ * @since 0.0.1
+ *
+ * Tries to lock @a spinlock and returns immediately if it is not available for
+ * locking.
+ *
+ * If the atomic model is not lock-free this call will have the same effect
+ * as p_mutex_trylock().
+ *
+ * Do not lock a spinlock recursively - this may lead to an application
+ * deadlock.
+ */
+P_LIB_API pboolean	p_spinlock_trylock	(PSpinLock *spinlock);
+
+/**
+ * @brief Releases a locked spinlock.
+ * @param spinlock #PSpinLock to release.
+ * @return TRUE in case of success, FALSE otherwise.
+ * @since 0.0.1
+ *
+ * If @a spinlock was previously locked then it becomes unlocked. Any thread
+ * can unlock any spinlock. It is also safe to call this routine on an unlocked
+ * spinlock.
+ *
+ * If the atomic model is not lock-free this call will have the same effect
+ * as p_mutex_unlock(), thus it is not safe to call this routine on an unlocked
+ * spinlock.
+ */
+P_LIB_API pboolean	p_spinlock_unlock	(PSpinLock *spinlock);
+
+/**
+ * @brief Frees #PSpinLock object.
+ * @param spinlock #PSpinLock to free.
+ * @since 0.0.1
+ *
+ * It doesn't unlock @a spinlock before freeing memory, so you should do it
+ * manually.
+ *
+ * If the atomic model is not lock-free this call will have the same effect
+ * as p_mutex_free().
+ */
+P_LIB_API void		p_spinlock_free		(PSpinLock *spinlock);
+
+P_END_DECLS
+
+#endif /* PLIBSYS_HEADER_PSPINLOCK_H */