1 | /* |
2 | * Copyright (C) 2013-2017 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 | * |
8 | * 1. Redistributions of source code must retain the above copyright |
9 | * notice, this list of conditions and the following disclaimer. |
10 | * 2. Redistributions in binary form must reproduce the above copyright |
11 | * notice, this list of conditions and the following disclaimer in the |
12 | * documentation and/or other materials provided with the distribution. |
13 | * |
14 | * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY |
15 | * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED |
16 | * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
17 | * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY |
18 | * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES |
19 | * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
20 | * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND |
21 | * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
22 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
23 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
24 | */ |
25 | |
26 | #pragma once |
27 | |
28 | #include "ArrayBufferView.h" |
29 | #include <wtf/FlipBytes.h> |
30 | |
31 | namespace JSC { |
32 | |
33 | class DataView : public ArrayBufferView { |
34 | protected: |
35 | DataView(RefPtr<ArrayBuffer>&&, unsigned byteOffset, unsigned byteLength); |
36 | |
37 | public: |
38 | JS_EXPORT_PRIVATE static Ref<DataView> create(RefPtr<ArrayBuffer>&&, unsigned byteOffset, unsigned length); |
39 | static Ref<DataView> create(RefPtr<ArrayBuffer>&&); |
40 | |
41 | TypedArrayType getType() const override |
42 | { |
43 | return TypeDataView; |
44 | } |
45 | |
46 | JSArrayBufferView* wrap(ExecState*, JSGlobalObject*) override; |
47 | |
48 | template<typename T> |
49 | T get(unsigned offset, bool littleEndian, bool* status = 0) |
50 | { |
51 | if (status) { |
52 | if (offset + sizeof(T) > byteLength()) { |
53 | *status = false; |
54 | return T(); |
55 | } |
56 | *status = true; |
57 | } else |
58 | RELEASE_ASSERT(offset + sizeof(T) <= byteLength()); |
59 | return flipBytesIfLittleEndian( |
60 | *reinterpret_cast<T*>(static_cast<uint8_t*>(m_baseAddress.get(byteLength())) + offset), |
61 | littleEndian); |
62 | } |
63 | |
64 | template<typename T> |
65 | T read(unsigned& offset, bool littleEndian, bool* status = 0) |
66 | { |
67 | T result = this->template get<T>(offset, littleEndian, status); |
68 | if (!status || *status) |
69 | offset += sizeof(T); |
70 | return result; |
71 | } |
72 | |
73 | template<typename T> |
74 | void set(unsigned offset, T value, bool littleEndian, bool* status = 0) |
75 | { |
76 | if (status) { |
77 | if (offset + sizeof(T) > byteLength()) { |
78 | *status = false; |
79 | return; |
80 | } |
81 | *status = true; |
82 | } else |
83 | RELEASE_ASSERT(offset + sizeof(T) <= byteLength()); |
84 | *reinterpret_cast<T*>(static_cast<uint8_t*>(m_baseAddress.get(byteLength())) + offset) = |
85 | flipBytesIfLittleEndian(value, littleEndian); |
86 | } |
87 | }; |
88 | |
89 | } // namespace JSC |
90 | |