AtomicOps.cpp

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#include "blocxx/BLOCXX_config.h"
#include "blocxx/AtomicOps.hpp"
 
#if defined(BLOCXX_USE_PTHREAD_SPIN_LOCK_ATOMIC_OPS)
 
namespace BLOCXX_NAMESPACE
{
 
Atomic_t::Atomic_t()
   : val(0)
{
   pthread_spin_init(&spinlock, 0);
}
Atomic_t::Atomic_t(int i)
   : val(i)
{
   pthread_spin_init(&spinlock, 0);
}
void AtomicInc(Atomic_t &v)
{
   pthread_spin_lock(&v.spinlock);
   ++v.val;
   pthread_spin_unlock(&v.spinlock);
}
bool AtomicDecAndTest(Atomic_t &v)
{
   pthread_spin_lock(&v.spinlock);
   --v.val;
   bool b = ((v.val == 0) ? true : false) ;
   pthread_spin_unlock(&v.spinlock);
   return b;
}
int AtomicGet(Atomic_t const &v)
{
   return v.val;
}
void AtomicDec(Atomic_t &v)
{
   pthread_spin_lock(&v.spinlock);
   --v.val;
   pthread_spin_unlock(&v.spinlock);
}
 
} // end namespace BLOCXX_NAMESPACE
 
#elif defined(BLOCXX_USE_BLOCXX_DEFAULT_ATOMIC_OPS)
#include "blocxx/Mutex.hpp"
#include "blocxx/MutexLock.hpp"
#include "blocxx/ThreadOnce.hpp"
 
namespace BLOCXX_NAMESPACE
{
 
// this needs to be a pointer because of static initialization order conflicts.  
// It shouldn't ever be deleted b/c it may be referenced by a destructor of a 
// static variable that is being deleted.
static Mutex* guard = 0;
static OnceFlag g_once = BLOCXX_ONCE_INIT;
static void initGuard()
{
   guard = new Mutex();
}
void AtomicInc(Atomic_t &v)
{
   callOnce(g_once, initGuard);
   MutexLock lock(*guard);
   ++v.val;
}
bool AtomicDecAndTest(Atomic_t &v)
{
   callOnce(g_once, initGuard);
   MutexLock lock(*guard);
   return --v.val == 0;
}
int AtomicGet(Atomic_t const &v)
{
   callOnce(g_once, initGuard);
   MutexLock lock(*guard);
   return v.val;
}
void AtomicDec(Atomic_t &v)
{
   callOnce(g_once, initGuard);
   MutexLock lock(*guard);
   --v.val;
}
 
} // end namespace BLOCXX_NAMESPACE
 
#endif