GMutex.h

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#ifndef G3D_GMutex_h
#define G3D_GMutex_h

#include "G3D/platform.h"
#include "G3D/AtomicInt32.h"
#include "G3D/debugAssert.h"
#include <string>

#ifndef G3D_WINDOWS
# include <pthread.h>
# include <signal.h>
#endif

#if defined(G3D_LINUX) || defined(G3D_OSX)
# include <unistd.h> // For usleep
#endif


namespace G3D {

class Spinlock {
private:

 AtomicInt32 x;

public:

 inline Spinlock() : x(0) {}

 inline bool lock() {
 bool first = true;
 while (x.compareAndSet(0, 1) == 1) {
 first = false;
# ifdef G3D_WINDOWS
 Sleep(0);
# else
 usleep(0);
# endif
 }
 return first;
 }

 inline void unlock() {
 x.compareAndSet(1, 0);
 }

};

class GMutex {
private:
# ifdef G3D_WINDOWS
 CRITICAL_SECTION m_handle;
# else
 pthread_mutex_t m_handle;
 pthread_mutexattr_t m_attr;
# endif

 // Not implemented on purpose, don't use
 GMutex(const GMutex &mlock);
 GMutex &operator=(const GMutex &);
 bool operator==(const GMutex&);

public:
 GMutex();
 ~GMutex();

 void lock();

 bool tryLock();

 void unlock();
};


class GMutexLock {
private:
 GMutex* m;

 // Not implemented on purpose, don't use
 GMutexLock(const GMutexLock &mlock);
 GMutexLock &operator=(const GMutexLock &);
 bool operator==(const GMutexLock&);

public:
 GMutexLock(GMutex* mutex) {
 m = mutex;
 m->lock();
 }

 ~GMutexLock() {
 m->unlock();
 }
};

} // G3D

#endif