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 #include "config.h"
27 #include "ArrayBuffer.h"
28 
29 #include <wtf/RefPtr.h>
30 
31 namespace WebCore {
32 
create(unsigned numElements,unsigned elementByteSize)33 PassRefPtr<ArrayBuffer> ArrayBuffer::create(unsigned numElements, unsigned elementByteSize)
34 {
35     void* data = tryAllocate(numElements, elementByteSize);
36     if (!data)
37         return 0;
38     return adoptRef(new ArrayBuffer(data, numElements * elementByteSize));
39 }
40 
create(ArrayBuffer * other)41 PassRefPtr<ArrayBuffer> ArrayBuffer::create(ArrayBuffer* other)
42 {
43     return ArrayBuffer::create(other->data(), other->byteLength());
44 }
45 
create(void * source,unsigned byteLength)46 PassRefPtr<ArrayBuffer> ArrayBuffer::create(void* source, unsigned byteLength)
47 {
48     void* data = tryAllocate(byteLength, 1);
49     if (!data)
50         return 0;
51     RefPtr<ArrayBuffer> buffer = adoptRef(new ArrayBuffer(data, byteLength));
52     memcpy(buffer->data(), source, byteLength);
53     return buffer.release();
54 }
55 
ArrayBuffer(void * data,unsigned sizeInBytes)56 ArrayBuffer::ArrayBuffer(void* data, unsigned sizeInBytes)
57     : m_sizeInBytes(sizeInBytes)
58     , m_data(data)
59 {
60 }
61 
data()62 void* ArrayBuffer::data()
63 {
64     return m_data;
65 }
66 
data() const67 const void* ArrayBuffer::data() const
68 {
69     return m_data;
70 }
71 
byteLength() const72 unsigned ArrayBuffer::byteLength() const
73 {
74     return m_sizeInBytes;
75 }
76 
~ArrayBuffer()77 ArrayBuffer::~ArrayBuffer()
78 {
79     WTF::fastFree(m_data);
80 }
81 
tryAllocate(unsigned numElements,unsigned elementByteSize)82 void* ArrayBuffer::tryAllocate(unsigned numElements, unsigned elementByteSize)
83 {
84     void* result;
85     // Do not allow 32-bit overflow of the total size.
86     // FIXME: Why not? The tryFastCalloc function already checks its arguments,
87     // and will fail if there is any overflow, so why should we include a
88     // redudant unnecessarily restrictive check here?
89     if (numElements) {
90         unsigned totalSize = numElements * elementByteSize;
91         if (totalSize / numElements != elementByteSize)
92             return 0;
93     }
94     if (WTF::tryFastCalloc(numElements, elementByteSize).getValue(result))
95         return result;
96     return 0;
97 }
98 
99 }
100