runtime/JSArrayBufferViewInlines.h

   1 /*
   2  * Copyright (C) 2013 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 #ifndef JSArrayBufferViewInlines_h
  27 #define JSArrayBufferViewInlines_h
  28
  29 #include "ArrayBufferView.h"
  30 #include "JSArrayBufferView.h"
  31 #include "JSDataView.h"
  32
  33 namespace JSC {
  34
  35 inline ArrayBuffer* JSArrayBufferView::buffer()
  36 {
  37     switch (m_mode) {
  38     case WastefulTypedArray:
  39         return existingBufferInButterfly();
  40     case DataViewMode:
  41         return jsCast<JSDataView*>(this)->buffer();
  42     default:
  43         return methodTable()->slowDownAndWasteMemory(this);
  44     }
  45 }
  46
  47 inline ArrayBuffer* JSArrayBufferView::existingBufferInButterfly()
  48 {
  49     ASSERT(m_mode == WastefulTypedArray);
  50     return butterfly()->indexingHeader()->arrayBuffer();
  51 }
  52
  53 inline PassRefPtr<ArrayBufferView> JSArrayBufferView::impl()
  54 {
  55     return methodTable()->getTypedArrayImpl(this);
  56 }
  57
  58 inline void JSArrayBufferView::neuter()
  59 {
  60     ASSERT(hasArrayBuffer());
  61     m_length = 0;
  62     m_vector = 0;
  63 }
  64
  65 inline unsigned JSArrayBufferView::byteOffset()
  66 {
  67     if (!hasArrayBuffer())
  68         return 0;
  69
  70     ptrdiff_t delta =
  71         static_cast<uint8_t*>(m_vector) - static_cast<uint8_t*>(buffer()->data());
  72
  73     unsigned result = static_cast<unsigned>(delta);
  74     ASSERT(static_cast<ptrdiff_t>(result) == delta);
  75     return result;
  76 }
  77
  78 } // namespace JSC
  79
  80 #endif // JSArrayBufferViewInlines_h
  81