dolphin/Externals/wxWidgets3/include/wx/atomic.h

161 lines
4.2 KiB
C
Raw Normal View History

/////////////////////////////////////////////////////////////////////////////
// Name: wx/atomic.h
// Purpose: functions to manipulate atomically integers and pointers
// Author: Armel Asselin
// Created: 12/13/2006
// RCS-ID: $Id: atomic.h 53954 2008-06-02 20:42:23Z VZ $
// Copyright: (c) Armel Asselin
// Licence: wxWindows licence
/////////////////////////////////////////////////////////////////////////////
#ifndef _WX_ATOMIC_H_
#define _WX_ATOMIC_H_
// ----------------------------------------------------------------------------
// headers
// ----------------------------------------------------------------------------
// get the value of wxUSE_THREADS configuration flag
#include "wx/defs.h"
// constraints on the various functions:
// - wxAtomicDec must return a zero value if the value is zero once
// decremented else it must return any non-zero value (the true value is OK
// but not necessary).
#if wxUSE_THREADS
#if defined(HAVE_GCC_ATOMIC_BUILTINS)
// NB: we intentionally don't use Linux's asm/atomic.h header, because it's
// an internal kernel header that doesn't always work in userspace:
// http://bugs.mysql.com/bug.php?id=28456
// http://golubenco.org/blog/atomic-operations/
inline void wxAtomicInc (wxUint32 &value)
{
__sync_fetch_and_add(&value, 1);
}
inline wxUint32 wxAtomicDec (wxUint32 &value)
{
return __sync_sub_and_fetch(&value, 1);
}
#elif defined(__WXMSW__)
// include standard Windows headers
#include "wx/msw/wrapwin.h"
inline void wxAtomicInc (wxUint32 &value)
{
InterlockedIncrement ((LONG*)&value);
}
inline wxUint32 wxAtomicDec (wxUint32 &value)
{
return InterlockedDecrement ((LONG*)&value);
}
#elif defined(__WXMAC__) || defined(__DARWIN__)
#include "libkern/OSAtomic.h"
inline void wxAtomicInc (wxUint32 &value)
{
OSAtomicIncrement32 ((int32_t*)&value);
}
inline wxUint32 wxAtomicDec (wxUint32 &value)
{
return OSAtomicDecrement32 ((int32_t*)&value);
}
#elif defined (__SOLARIS__)
#include <atomic.h>
inline void wxAtomicInc (wxUint32 &value)
{
atomic_add_32 ((uint32_t*)&value, 1);
}
inline wxUint32 wxAtomicDec (wxUint32 &value)
{
return atomic_add_32_nv ((uint32_t*)&value, (uint32_t)-1);
}
#else // unknown platform
// it will result in inclusion if the generic implementation code a bit later in this page
#define wxNEEDS_GENERIC_ATOMIC_OPS
#endif // unknown platform
#else // else of wxUSE_THREADS
// if no threads are used we can safely use simple ++/--
inline void wxAtomicInc (wxUint32 &value) { ++value; }
inline wxUint32 wxAtomicDec (wxUint32 &value) { return --value; }
#endif // !wxUSE_THREADS
// ----------------------------------------------------------------------------
// proxies to actual implementations, but for various other types with same
// behaviour
// ----------------------------------------------------------------------------
#ifdef wxNEEDS_GENERIC_ATOMIC_OPS
#include "wx/thread.h" // for wxCriticalSection
class wxAtomicInt32
{
public:
wxAtomicInt32() { } // non initialized for consistency with basic int type
wxAtomicInt32(wxInt32 v) : m_value(v) { }
wxAtomicInt32(const wxAtomicInt32& a) : m_value(a.m_value) {}
operator wxInt32() const { return m_value; }
operator volatile wxInt32&() { return m_value; }
wxAtomicInt32& operator=(wxInt32 v) { m_value = v; return *this; }
void Inc()
{
wxCriticalSectionLocker lock(m_locker);
++m_value;
}
wxInt32 Dec()
{
wxCriticalSectionLocker lock(m_locker);
return --m_value;
}
private:
volatile wxInt32 m_value;
wxCriticalSection m_locker;
};
inline void wxAtomicInc(wxAtomicInt32 &value) { value.Inc(); }
inline wxInt32 wxAtomicDec(wxAtomicInt32 &value) { return value.Dec(); }
#else // !wxNEEDS_GENERIC_ATOMIC_OPS
#define wxHAS_ATOMIC_OPS
inline void wxAtomicInc(wxInt32 &value) { wxAtomicInc((wxUint32&)value); }
inline wxInt32 wxAtomicDec(wxInt32 &value) { return wxAtomicDec((wxUint32&)value); }
typedef wxInt32 wxAtomicInt32;
#endif // wxNEEDS_GENERIC_ATOMIC_OPS
// all the native implementations use 32 bits currently
// for a 64 bits implementation we could use (a future) wxAtomicInt64 as
// default type
typedef wxAtomicInt32 wxAtomicInt;
#endif // _WX_ATOMIC_H_