Add PISpinlock and PISpinlockLocker

CMakeLists.txt

@@ -3,7 +3,7 @@ cmake_policy(SET CMP0017 NEW) # need include() with .cmake
 project(pip)
 set(pip_MAJOR    2)
 set(pip_MINOR    9)
-set(pip_REVISION 0)
+set(pip_REVISION 1)
 set(pip_SUFFIX   )
 set(pip_COMPANY  SHS)
 set(pip_DOMAIN   org.SHS)

libs/main/thread/pimutex.cpp

@@ -1,6 +1,6 @@
 /*
 	PIP - Platform Independent Primitives
-	Mutex
+	PIMutex, PIMutexLocker
 	Ivan Pelipenko peri4ko@yandex.ru, Stephan Fomenko, Andrey Bychkov work.a.b@yandex.ru
 
 	This program is free software: you can redistribute it and/or modify

libs/main/thread/pimutex.h

@@ -1,9 +1,9 @@
 /*! \file pimutex.h
- * \brief PIMutexLocker
+ * \brief PIMutex, PIMutexLocker
 */
 /*
 	PIP - Platform Independent Primitives
-	PIMutexLocker
+	PIMutex, PIMutexLocker
 	Ivan Pelipenko peri4ko@yandex.ru, Stephan Fomenko, Andrey Bychkov work.a.b@yandex.ru
 
 	This program is free software: you can redistribute it and/or modify

libs/main/thread/pispinlock.cpp

@@ -0,0 +1,30 @@
+/*
+	PIP - Platform Independent Primitives
+	PISpinlock
+	Ivan Pelipenko peri4ko@yandex.ru
+
+	This program 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 3 of the License, or
+	(at your option) any later version.
+
+	This program 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 program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+/** \class PISpinlock
+ * \brief Spinlock
+ * \details
+ * \section PISpinlock_sec0 Synopsis
+ * %PISpinlock provides synchronization blocks between several threads.
+ * PISpinlock functionality similar to PIMutex, but working on atomic
+ * type and \a lock() method wait with 100% CPU load.
+ * \note
+ * Use this type instead of PIMutex when less waiting time is more
+ * important than CPU load!
+ * */

libs/main/thread/pispinlock.h

@@ -0,0 +1,75 @@
+/*! \file pispinlock.h
+ * \brief PISpinlock
+*/
+/*
+	PIP - Platform Independent Primitives
+	PISpinlock
+	Ivan Pelipenko peri4ko@yandex.ru
+
+	This program 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 3 of the License, or
+	(at your option) any later version.
+
+	This program 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 program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef PISPINLOCK_H
+#define PISPINLOCK_H
+
+#include "piinit.h"
+#include <atomic>
+
+
+class PIP_EXPORT PISpinlock
+{
+public:
+	NO_COPY_CLASS(PISpinlock)
+
+	//! Constructs unlocked spinlock
+	explicit PISpinlock() {flag.clear();}
+
+	//! Destroy spinlock
+	~PISpinlock() {}
+
+
+	//! \brief Lock spinlock
+	//! \details If spinlock is unlocked it set to locked state and returns immediate.
+	//! If spinlock is already locked function blocks until spinlock will be unlocked
+	void lock() {while (flag.test_and_set(std::memory_order_acquire));}
+
+	//! \brief Unlock spinlock
+	//! \details In any case this function returns immediate
+	void unlock() {flag.clear(std::memory_order_release);}
+
+private:
+	std::atomic_flag flag;
+
+};
+
+
+//! \brief PISpinlockLocker
+//! \details
+//! When a PISpinlockLocker object is created, it attempts to lock the spinlock it is given, if "condition" true.
+//! When control leaves the scope in which the PISpinlockLocker object was created,
+//! the PISpinlockLocker is destructed and the spinlock is released, if "condition" true.
+//! If "condition" false this class do nothing.
+//! The PISpinlockLocker class is non-copyable.
+class PIP_EXPORT PISpinlockLocker
+{
+public:
+	NO_COPY_CLASS(PISpinlockLocker)
+	PISpinlockLocker(PISpinlock & s, bool condition = true): spinlock(s), cond(condition) {if (cond) spinlock.lock();}
+	~PISpinlockLocker() {if (cond) spinlock.unlock();}
+private:
+	PISpinlock & spinlock;
+	bool cond;
+};
+
+#endif // PISPINLOCK_H

libs/main/thread/pithreadmodule.h

@@ -21,6 +21,7 @@
 #define PITHREADMODULE_H
 
 #include "pimutex.h"
+#include "pispinlock.h"
 #include "pithread.h"
 #include "pitimer.h"
 #include "pipipelinethread.h"