git.saurik.com Git - apple/javascriptcore.git/blame_incremental

... / ...

Commit	Line	Data
	1	/*
	2	* Copyright (C) 2009, 2012, 2013 Apple Inc. All rights reserved.
	3	*
	4	* Redistribution and use in source and binary forms, with or without
	5	* modification, are permitted provided that the following conditions
	6	* are met:
	7	* 1. Redistributions of source code must retain the above copyright
	8	* notice, this list of conditions and the following disclaimer.
	9	* 2. Redistributions in binary form must reproduce the above copyright
	10	* notice, this list of conditions and the following disclaimer in the
	11	* documentation and/or other materials provided with the distribution.
	12	*
	13	* THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
	14	* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
	15	* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
	16	* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
	17	* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
	18	* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
	19	* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
	20	* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
	21	* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
	22	* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
	23	* THE POSSIBILITY OF SUCH DAMAGE.
	24	*/
	25
	26	#ifndef Weak_h
	27	#define Weak_h
	28
	29	#include <cstddef>
	30	#include <wtf/Noncopyable.h>
	31
	32	namespace JSC {
	33
	34	class WeakImpl;
	35	class WeakHandleOwner;
	36
	37	// This is a free function rather than a Weak<T> member function so we can put it in Weak.cpp.
	38	JS_EXPORT_PRIVATE void weakClearSlowCase(WeakImpl*&);
	39
	40	template<typename T> class Weak {
	41	WTF_MAKE_NONCOPYABLE(Weak);
	42	public:
	43	Weak()
	44	: m_impl(0)
	45	{
	46	}
	47
	48	Weak(std::nullptr_t)
	49	: m_impl(0)
	50	{
	51	}
	52
	53	Weak(T, WeakHandleOwner = 0, void* context = 0);
	54
	55	enum HashTableDeletedValueTag { HashTableDeletedValue };
	56	bool isHashTableDeletedValue() const;
	57	Weak(HashTableDeletedValueTag);
	58
	59	Weak(Weak&&);
	60
	61	~Weak()
	62	{
	63	clear();
	64	}
	65
	66	void swap(Weak&);
	67
	68	Weak& operator=(Weak&&);
	69
	70	bool operator!() const;
	71	T* operator->() const;
	72	T& operator*() const;
	73	T* get() const;
	74
	75	bool was(T*) const;
	76
	77	// This conversion operator allows implicit conversion to bool but not to other integer types.
	78	typedef void* (Weak::*UnspecifiedBoolType);
	79	operator UnspecifiedBoolType*() const;
	80
	81	WeakImpl* leakImpl() WARN_UNUSED_RETURN;
	82	void clear()
	83	{
	84	if (!m_impl)
	85	return;
	86	weakClearSlowCase(m_impl);
	87	}
	88
	89	private:
	90	static WeakImpl* hashTableDeletedValue();
	91
	92	WeakImpl* m_impl;
	93	};
	94
	95	} // namespace JSC
	96
	97	#endif // Weak_h