1/*
2 * Copyright (C) 2013, 2016 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#pragma once
27
28#include "ArrayBufferView.h"
29#include "JSArrayBufferView.h"
30#include "JSDataView.h"
31
32namespace JSC {
33
34inline bool JSArrayBufferView::isShared()
35{
36 switch (m_mode) {
37 case WastefulTypedArray:
38 return existingBufferInButterfly()->isShared();
39 case DataViewMode:
40 return jsCast<JSDataView*>(this)->possiblySharedBuffer()->isShared();
41 default:
42 return false;
43 }
44}
45
46inline ArrayBuffer* JSArrayBufferView::possiblySharedBuffer()
47{
48 switch (m_mode) {
49 case WastefulTypedArray:
50 return existingBufferInButterfly();
51 case DataViewMode:
52 return jsCast<JSDataView*>(this)->possiblySharedBuffer();
53 case FastTypedArray:
54 case OversizeTypedArray:
55 return slowDownAndWasteMemory();
56 }
57 ASSERT_NOT_REACHED();
58 return nullptr;
59}
60
61inline ArrayBuffer* JSArrayBufferView::existingBufferInButterfly()
62{
63 ASSERT(m_mode == WastefulTypedArray);
64 return butterfly()->indexingHeader()->arrayBuffer();
65}
66
67inline RefPtr<ArrayBufferView> JSArrayBufferView::unsharedImpl()
68{
69 RefPtr<ArrayBufferView> result = possiblySharedImpl();
70 RELEASE_ASSERT(!result->isShared());
71 return result;
72}
73
74inline unsigned JSArrayBufferView::byteOffset()
75{
76 if (!hasArrayBuffer())
77 return 0;
78
79 ArrayBuffer* buffer = possiblySharedBuffer();
80 ASSERT(!vector() == !buffer->data());
81
82 ptrdiff_t delta =
83 bitwise_cast<uint8_t*>(vector()) - static_cast<uint8_t*>(buffer->data());
84
85 unsigned result = static_cast<unsigned>(delta);
86 ASSERT(static_cast<ptrdiff_t>(result) == delta);
87 return result;
88}
89
90inline RefPtr<ArrayBufferView> JSArrayBufferView::toWrapped(VM& vm, JSValue value)
91{
92 if (JSArrayBufferView* view = jsDynamicCast<JSArrayBufferView*>(vm, value)) {
93 if (!view->isShared())
94 return view->unsharedImpl();
95 }
96 return nullptr;
97}
98
99} // namespace JSC
100