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 COMPUTER, 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 COMPUTER, 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 ArrayBuffer_h
27 #define ArrayBuffer_h
28
29 #include "wtf/ArrayBufferContents.h"
30 #include "wtf/HashSet.h"
31 #include "wtf/PassRefPtr.h"
32 #include "wtf/RefCounted.h"
33 #include "wtf/Vector.h"
34 #include "wtf/WTFExport.h"
35
36 namespace WTF {
37
38 class ArrayBuffer;
39 class ArrayBufferView;
40
41 class WTF_EXPORT ArrayBuffer : public RefCounted<ArrayBuffer> {
42 public:
43 static inline PassRefPtr<ArrayBuffer> create(unsigned numElements, unsigned elementByteSize);
44 static inline PassRefPtr<ArrayBuffer> create(ArrayBuffer*);
45 static inline PassRefPtr<ArrayBuffer> create(const void* source, unsigned byteLength);
46 static inline PassRefPtr<ArrayBuffer> create(ArrayBufferContents&);
47
48 // Only for use by Uint8ClampedArray::createUninitialized and SharedBuffer::getAsArrayBuffer.
49 static inline PassRefPtr<ArrayBuffer> createUninitialized(unsigned numElements, unsigned elementByteSize);
50
51 inline void* data();
52 inline const void* data() const;
53 inline unsigned byteLength() const;
54
55 // Creates a new ArrayBuffer object with copy of bytes in this object
56 // ranging from |begin| upto but not including |end|.
57 inline PassRefPtr<ArrayBuffer> slice(int begin, int end) const;
58 inline PassRefPtr<ArrayBuffer> slice(int begin) const;
59
60 void addView(ArrayBufferView*);
61 void removeView(ArrayBufferView*);
62
63 bool transfer(ArrayBufferContents&);
isNeutered()64 bool isNeutered() { return m_isNeutered; }
65
setDeallocationObserver(ArrayBufferDeallocationObserver * observer)66 void setDeallocationObserver(ArrayBufferDeallocationObserver* observer) { m_contents.setDeallocationObserver(observer); }
67
~ArrayBuffer()68 ~ArrayBuffer() { }
69
70 private:
71 static inline PassRefPtr<ArrayBuffer> create(unsigned numElements, unsigned elementByteSize, ArrayBufferContents::InitializationPolicy);
72
73 inline ArrayBuffer(ArrayBufferContents&);
74 inline PassRefPtr<ArrayBuffer> sliceImpl(unsigned begin, unsigned end) const;
75 inline unsigned clampIndex(int index) const;
76 static inline int clampValue(int x, int left, int right);
77
78 ArrayBufferContents m_contents;
79 ArrayBufferView* m_firstView;
80 bool m_isNeutered;
81 };
82
clampValue(int x,int left,int right)83 int ArrayBuffer::clampValue(int x, int left, int right)
84 {
85 ASSERT(left <= right);
86 if (x < left)
87 x = left;
88 if (right < x)
89 x = right;
90 return x;
91 }
92
create(unsigned numElements,unsigned elementByteSize)93 PassRefPtr<ArrayBuffer> ArrayBuffer::create(unsigned numElements, unsigned elementByteSize)
94 {
95 return create(numElements, elementByteSize, ArrayBufferContents::ZeroInitialize);
96 }
97
create(ArrayBuffer * other)98 PassRefPtr<ArrayBuffer> ArrayBuffer::create(ArrayBuffer* other)
99 {
100 return ArrayBuffer::create(other->data(), other->byteLength());
101 }
102
create(const void * source,unsigned byteLength)103 PassRefPtr<ArrayBuffer> ArrayBuffer::create(const void* source, unsigned byteLength)
104 {
105 ArrayBufferContents contents(byteLength, 1, ArrayBufferContents::ZeroInitialize);
106 if (!contents.data())
107 return nullptr;
108 RefPtr<ArrayBuffer> buffer = adoptRef(new ArrayBuffer(contents));
109 memcpy(buffer->data(), source, byteLength);
110 return buffer.release();
111 }
112
create(ArrayBufferContents & contents)113 PassRefPtr<ArrayBuffer> ArrayBuffer::create(ArrayBufferContents& contents)
114 {
115 return adoptRef(new ArrayBuffer(contents));
116 }
117
createUninitialized(unsigned numElements,unsigned elementByteSize)118 PassRefPtr<ArrayBuffer> ArrayBuffer::createUninitialized(unsigned numElements, unsigned elementByteSize)
119 {
120 return create(numElements, elementByteSize, ArrayBufferContents::DontInitialize);
121 }
122
create(unsigned numElements,unsigned elementByteSize,ArrayBufferContents::InitializationPolicy policy)123 PassRefPtr<ArrayBuffer> ArrayBuffer::create(unsigned numElements, unsigned elementByteSize, ArrayBufferContents::InitializationPolicy policy)
124 {
125 ArrayBufferContents contents(numElements, elementByteSize, policy);
126 if (!contents.data())
127 return nullptr;
128 return adoptRef(new ArrayBuffer(contents));
129 }
130
ArrayBuffer(ArrayBufferContents & contents)131 ArrayBuffer::ArrayBuffer(ArrayBufferContents& contents)
132 : m_firstView(0), m_isNeutered(false)
133 {
134 contents.transfer(m_contents);
135 }
136
data()137 void* ArrayBuffer::data()
138 {
139 return m_contents.data();
140 }
141
data()142 const void* ArrayBuffer::data() const
143 {
144 return m_contents.data();
145 }
146
byteLength()147 unsigned ArrayBuffer::byteLength() const
148 {
149 return m_contents.sizeInBytes();
150 }
151
slice(int begin,int end)152 PassRefPtr<ArrayBuffer> ArrayBuffer::slice(int begin, int end) const
153 {
154 return sliceImpl(clampIndex(begin), clampIndex(end));
155 }
156
slice(int begin)157 PassRefPtr<ArrayBuffer> ArrayBuffer::slice(int begin) const
158 {
159 return sliceImpl(clampIndex(begin), byteLength());
160 }
161
sliceImpl(unsigned begin,unsigned end)162 PassRefPtr<ArrayBuffer> ArrayBuffer::sliceImpl(unsigned begin, unsigned end) const
163 {
164 unsigned size = begin <= end ? end - begin : 0;
165 return ArrayBuffer::create(static_cast<const char*>(data()) + begin, size);
166 }
167
clampIndex(int index)168 unsigned ArrayBuffer::clampIndex(int index) const
169 {
170 unsigned currentLength = byteLength();
171 if (index < 0)
172 index = currentLength + index;
173 return clampValue(index, 0, currentLength);
174 }
175
176 } // namespace WTF
177
178 using WTF::ArrayBuffer;
179
180 #endif // ArrayBuffer_h
181