try using conditions for semaphores; standard semaphores are apparently too hard for OSX

This commit is contained in:
Glenn Maynard
2004-06-16 04:23:50 +00:00
parent cd59c6a68b
commit 2ec6b55568
2 changed files with 75 additions and 0 deletions
@@ -222,6 +222,7 @@ MutexImpl *MakeMutex( RageMutex *pParent )
return new MutexImpl_Pthreads( pParent );
}
#if 0
SemaImpl_Pthreads::SemaImpl_Pthreads( int iInitialValue )
{
sem_init( &sem, 0, iInitialValue );
@@ -267,6 +268,61 @@ bool SemaImpl_Pthreads::TryWait()
RageException::Throw( "TryWait: sem_trywait failed: %s", strerror(errno) );
return true;
}
#else
/* Use conditions, to work around OSX "forgetting" to implement semaphores. */
SemaImpl_Pthreads::SemaImpl_Pthreads( int iInitialValue )
{
int ret = pthread_cond_init( &m_Cond, NULL );
ASSERT_M( ret == 0, ssprintf( "SemaImpl_Pthreads: pthread_cond_init: %s", strerror(errno)) );
ret = pthread_mutex_init( &m_Mutex, NULL );
ASSERT_M( ret == 0, ssprintf( "SemaImpl_Pthreads: pthread_mutex_init: %s", strerror(errno)) );
m_iValue = iInitialValue;
}
SemaImpl_Pthreads::~SemaImpl_Pthreads()
{
pthread_cond_destroy( &m_Cond );
pthread_mutex_destroy( &m_Mutex );
}
void SemaImpl_Pthreads::Post()
{
pthread_mutex_lock( &m_Mutex );
++m_iValue;
if( m_iValue == 1 )
pthread_cond_signal( &m_Cond );
pthread_mutex_unlock( &m_Mutex );
}
bool SemaImpl_Pthreads::Wait()
{
pthread_mutex_lock( &m_Mutex );
while( !m_iValue )
pthread_cond_wait( &m_Cond, &m_Mutex );
--m_iValue;
pthread_mutex_unlock( &m_Mutex);
return true;
}
bool SemaImpl_Pthreads::TryWait()
{
pthread_mutex_lock( &m_Mutex );
if( !m_iValue )
{
pthread_mutex_unlock( &m_Mutex);
return false;
}
--m_iValue;
pthread_mutex_unlock( &m_Mutex);
return true;
}
#endif
SemaImpl *MakeSemaphore( int iInitialValue )
{
@@ -53,6 +53,7 @@ private:
pthread_mutex_t mutex;
};
#if 0
class SemaImpl_Pthreads: public SemaImpl
{
public:
@@ -66,6 +67,24 @@ public:
private:
sem_t sem;
};
#else
class SemaImpl_Pthreads: public SemaImpl
{
public:
SemaImpl_Pthreads( int iInitialValue );
~SemaImpl_Pthreads();
int GetValue() const { return m_iValue; }
void Post();
bool Wait();
bool TryWait();
private:
pthread_cond_t m_Cond;
pthread_mutex_t m_Mutex;
unsigned m_iValue;
};
#endif
#endif