Just a mutex class

TinyMutex.h

#ifndef TinyMutex_h
#define TinyMutex_h

#if defined(_WIN32) || defined(__WIN32__)
    #define WIN32_LEAN_AND_MEAN
    #include <windows.h>
    #include <process.h>
#elif defined(__GNUC__)
    #include <pthread.h>
#endif

class TinyMutex
{
public:
    TinyMutex()
    {
#if defined(_WIN32) || defined(__WIN32__)
        _mutex = CreateMutex(0, FALSE, 0);
#elif defined(__GNUC__)
        pthread_mutex_init(&_mutex, NULL);
#endif
    }
    
    ~TinyMutex()
    {
#if defined(_WIN32) || defined(__WIN32__)
        CloseHandle(_mutex);
#elif defined(__GNUC__)
        pthread_mutex_destroy(&_mutex);
#endif
    }
    
    bool lock()
    {
#if defined(_WIN32) || defined(__WIN32__)
        return WaitForSingleObject(_mutex, INFINITE) != WAIT_FAILED;
#elif defined(__GNUC__)
        return pthread_mutex_lock(&_mutex) == 0;
#endif
        return false;
    }
    
    bool unlock()
    {
#if defined(_WIN32) || defined(__WIN32__)
        return ReleaseMutex(_mutex) == TRUE;
#elif defined(__GNUC__)
        return pthread_mutex_unlock(&_mutex) == 0;
#endif
        return false;
    }

private:
#if defined(_WIN32) || defined(__WIN32__)
    HANDLE _mutex;
#elif defined(__GNUC__)
    pthread_mutex_t _mutex;
#endif
};

#endif