safe_refcount.h | Explore in Territory

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/*  safe_refcount.h                                                       */
/**************************************************************************/
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#ifndef SAFE_REFCOUNT_H
#define SAFE_REFCOUNT_H

#include "core/typedefs.h"

#ifdef DEV_ENABLED
#include "core/error/error_macros.h"
#endif

#include <atomic>
#include <type_traits>

// Design goals for these classes:
// - No automatic conversions or arithmetic operators,
//   to keep explicit the use of atomics everywhere.
// - Using acquire-release semantics, even to set the first value.
//   The first value may be set relaxedly in many cases, but adding the distinction
//   between relaxed and unrelaxed operation to the interface would make it needlessly
//   flexible. There's negligible waste in having release semantics for the initial
//   value and, as an important benefit, you can be sure the value is properly synchronized
//   even with threads that are already running.

// These are used in very specific areas of the engine where it's critical that these guarantees are held
#define SAFE_NUMERIC_TYPE_PUN_GUARANTEES(m_type) …
#define SAFE_FLAG_TYPE_PUN_GUARANTEES …

template <typename T>
class SafeNumeric { … };

class SafeFlag { … };

class SafeRefCount { … };

#endif // SAFE_REFCOUNT_H
godot/core/templates/safe_refcount.h
