1/*
2 * Copyright (C) 2009 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. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#ifndef JSByteArray_h
27#define JSByteArray_h
28
29#include "JSObject.h"
30
31#include <wtf/ByteArray.h>
32
33namespace JSC {
34
35    class JSByteArray : public JSNonFinalObject {
36        friend class JSGlobalData;
37    public:
38        typedef JSNonFinalObject Base;
39
40        bool canAccessIndex(unsigned i) { return i < m_storage->length(); }
41        JSValue getIndex(ExecState*, unsigned i)
42        {
43            ASSERT(canAccessIndex(i));
44            return jsNumber(m_storage->data()[i]);
45        }
46
47        void setIndex(unsigned i, int value)
48        {
49            ASSERT(canAccessIndex(i));
50            if (value & ~0xFF) {
51                if (value < 0)
52                    value = 0;
53                else
54                    value = 255;
55            }
56            m_storage->data()[i] = static_cast<unsigned char>(value);
57        }
58
59        void setIndex(unsigned i, double value)
60        {
61            ASSERT(canAccessIndex(i));
62            if (!(value > 0)) // Clamp NaN to 0
63                value = 0;
64            else if (value > 255)
65                value = 255;
66            m_storage->data()[i] = static_cast<unsigned char>(value + 0.5);
67        }
68
69        void setIndex(ExecState* exec, unsigned i, JSValue value)
70        {
71            double byteValue = value.toNumber(exec);
72            if (exec->hadException())
73                return;
74            if (canAccessIndex(i))
75                setIndex(i, byteValue);
76        }
77
78        JSByteArray(ExecState*, Structure*, WTF::ByteArray* storage);
79        static Structure* createStructure(JSGlobalData&, JSValue prototype, const JSC::ClassInfo* = &s_defaultInfo);
80
81        virtual bool getOwnPropertySlot(JSC::ExecState*, const JSC::Identifier& propertyName, JSC::PropertySlot&);
82        virtual bool getOwnPropertySlot(JSC::ExecState*, unsigned propertyName, JSC::PropertySlot&);
83        virtual bool getOwnPropertyDescriptor(ExecState*, const Identifier&, PropertyDescriptor&);
84        virtual void put(JSC::ExecState*, const JSC::Identifier& propertyName, JSC::JSValue, JSC::PutPropertySlot&);
85        virtual void put(JSC::ExecState*, unsigned propertyName, JSC::JSValue);
86
87        virtual void getOwnPropertyNames(JSC::ExecState*, JSC::PropertyNameArray&, EnumerationMode mode = ExcludeDontEnumProperties);
88
89        static const ClassInfo s_defaultInfo;
90
91        size_t length() const { return m_storage->length(); }
92
93        WTF::ByteArray* storage() const { return m_storage.get(); }
94
95#if !ASSERT_DISABLED
96        virtual ~JSByteArray();
97#endif
98
99    protected:
100        static const unsigned StructureFlags = OverridesGetOwnPropertySlot | OverridesGetPropertyNames | JSObject::StructureFlags;
101
102    private:
103        JSByteArray(VPtrStealingHackType)
104            : JSNonFinalObject(VPtrStealingHack)
105        {
106        }
107
108        RefPtr<WTF::ByteArray> m_storage;
109    };
110
111    JSByteArray* asByteArray(JSValue value);
112    inline JSByteArray* asByteArray(JSValue value)
113    {
114        return static_cast<JSByteArray*>(value.asCell());
115    }
116
117    inline bool isJSByteArray(JSGlobalData* globalData, JSValue v) { return v.isCell() && v.asCell()->vptr() == globalData->jsByteArrayVPtr; }
118
119} // namespace JSC
120
121#endif // JSByteArray_h
122