1 files changed, 80 insertions, 0 deletions

diff --git a/src/OSSupport/CriticalSection.h b/src/OSSupport/CriticalSection.h
new file mode 100644
index 000000000..1bfe81439
--- /dev/null
+++ b/src/OSSupport/CriticalSection.h
@@ -0,0 +1,80 @@
+
+#pragma once
+
+
+
+
+
+class cCriticalSection
+{
+public:
+	cCriticalSection(void);
+	~cCriticalSection();
+
+	void Lock(void);
+	void Unlock(void);
+	
+	#ifdef _DEBUG
+	bool IsLocked(void);
+	bool IsLockedByCurrentThread(void);
+	#endif  // _DEBUG
+	
+private:
+	#ifdef _DEBUG
+	int           m_IsLocked;  // Number of times this CS is locked
+	unsigned long m_OwningThreadID;
+	#endif  // _DEBUG
+	
+	#ifdef _WIN32
+		CRITICAL_SECTION m_CriticalSection;
+	#else  // _WIN32
+		pthread_mutex_t     m_CriticalSection;
+		pthread_mutexattr_t m_Attributes;
+	#endif  // else _WIN32
+} ALIGN_8;
+
+
+
+
+/// RAII for cCriticalSection - locks the CS on creation, unlocks on destruction
+class cCSLock
+{
+	cCriticalSection * m_CS;
+
+	// Unlike a cCriticalSection, this object should be used from a single thread, therefore access to m_IsLocked is not threadsafe
+	// In Windows, it is an error to call cCriticalSection::Unlock() multiple times if the lock is not held, 
+	// therefore we need to check this value whether we are locked or not.
+	bool m_IsLocked;
+	
+public:
+	cCSLock(cCriticalSection * a_CS);
+	cCSLock(cCriticalSection & a_CS);
+	~cCSLock();
+	
+	// Temporarily unlock or re-lock:
+	void Lock(void);
+	void Unlock(void);
+
+private:
+	DISALLOW_COPY_AND_ASSIGN(cCSLock);
+} ;
+
+
+
+
+
+/// Temporary RAII unlock for a cCSLock. Useful for unlock-wait-relock scenarios
+class cCSUnlock
+{
+	cCSLock & m_Lock;
+public:
+	cCSUnlock(cCSLock & a_Lock);
+	~cCSUnlock();
+	
+private:
+	DISALLOW_COPY_AND_ASSIGN(cCSUnlock);
+} ;
+
+
+
+