1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189
|
/*
* Copyright (C) 2011 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
* THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef Handle_h
#define Handle_h
#include "HandleTypes.h"
namespace JSC {
/*
A Handle is a smart pointer that updates automatically when the garbage
collector moves the object to which it points.
The base Handle class represents a temporary reference to a pointer whose
lifetime is guaranteed by something else.
*/
template <class T> class Handle;
// Creating a JSValue Handle is invalid
template <> class Handle<JSValue>;
class HandleBase {
template <typename T> friend class Weak;
template <typename T> friend class Strong;
friend class HandleSet;
friend struct JSCallbackObjectData;
public:
bool operator!() const { return !m_slot || !*m_slot; }
// This conversion operator allows implicit conversion to bool but not to other integer types.
typedef JSValue (HandleBase::*UnspecifiedBoolType);
operator UnspecifiedBoolType*() const { return (m_slot && *m_slot) ? reinterpret_cast<UnspecifiedBoolType*>(1) : 0; }
HandleSlot slot() const { return m_slot; }
protected:
HandleBase(HandleSlot slot)
: m_slot(slot)
{
}
void swap(HandleBase& other) { std::swap(m_slot, other.m_slot); }
void setSlot(HandleSlot slot)
{
m_slot = slot;
}
private:
HandleSlot m_slot;
};
template <typename Base, typename T> struct HandleConverter {
T* operator->()
{
return static_cast<Base*>(this)->get();
}
const T* operator->() const
{
return static_cast<const Base*>(this)->get();
}
T* operator*()
{
return static_cast<Base*>(this)->get();
}
const T* operator*() const
{
return static_cast<const Base*>(this)->get();
}
};
template <typename Base> struct HandleConverter<Base, Unknown> {
Handle<JSObject> asObject() const;
bool isObject() const { return jsValue().isObject(); }
bool getNumber(double number) const { return jsValue().getNumber(number); }
WTF::String getString(ExecState*) const;
bool isUndefinedOrNull() const { return jsValue().isUndefinedOrNull(); }
private:
JSValue jsValue() const
{
return static_cast<const Base*>(this)->get();
}
};
template <typename T> class Handle : public HandleBase, public HandleConverter<Handle<T>, T> {
public:
template <typename A, typename B> friend struct HandleConverter;
typedef typename HandleTypes<T>::ExternalType ExternalType;
template <typename U> Handle(Handle<U> o)
{
typename HandleTypes<T>::template validateUpcast<U>();
setSlot(o.slot());
}
void swap(Handle& other) { HandleBase::swap(other); }
ExternalType get() const { return HandleTypes<T>::getFromSlot(this->slot()); }
protected:
Handle(HandleSlot slot = 0)
: HandleBase(slot)
{
}
private:
friend class HandleSet;
friend class WeakBlock;
static Handle<T> wrapSlot(HandleSlot slot)
{
return Handle<T>(slot);
}
};
template <typename Base> Handle<JSObject> HandleConverter<Base, Unknown>::asObject() const
{
return Handle<JSObject>::wrapSlot(static_cast<const Base*>(this)->slot());
}
template <typename T, typename U> inline bool operator==(const Handle<T>& a, const Handle<U>& b)
{
return a.get() == b.get();
}
template <typename T, typename U> inline bool operator==(const Handle<T>& a, U* b)
{
return a.get() == b;
}
template <typename T, typename U> inline bool operator==(T* a, const Handle<U>& b)
{
return a == b.get();
}
template <typename T, typename U> inline bool operator!=(const Handle<T>& a, const Handle<U>& b)
{
return a.get() != b.get();
}
template <typename T, typename U> inline bool operator!=(const Handle<T>& a, U* b)
{
return a.get() != b;
}
template <typename T, typename U> inline bool operator!=(T* a, const Handle<U>& b)
{
return a != b.get();
}
template <typename T, typename U> inline bool operator!=(const Handle<T>& a, JSValue b)
{
return a.get() != b;
}
template <typename T, typename U> inline bool operator!=(JSValue a, const Handle<U>& b)
{
return a != b.get();
}
}
#endif
|