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