third_party/WebKit/Source/wtf/ArrayBuffer.cpp

   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 "wtf/ArrayBuffer.h"
  28
  29 #include "wtf/ArrayBufferView.h"
  30 #include "wtf/RefPtr.h"
  31
  32 namespace WTF {
  33
  34 bool ArrayBuffer::transfer(ArrayBufferContents& result)
  35 {
  36     ASSERT(!isShared());
  37     RefPtr<ArrayBuffer> keepAlive(this);
  38
  39     if (!m_contents.data()) {
  40         result.neuter();
  41         return false;
  42     }
  43
  44     bool allViewsAreNeuterable = true;
  45     for (ArrayBufferView* i = m_firstView; i; i = i->m_nextView) {
  46         if (!i->isNeuterable())
  47             allViewsAreNeuterable = false;
  48     }
  49
  50     if (allViewsAreNeuterable) {
  51         m_contents.transfer(result);
  52     } else {
  53         m_contents.copyTo(result);
  54         if (!result.data())
  55             return false;
  56     }
  57
  58     while (m_firstView) {
  59         ArrayBufferView* current = m_firstView;
  60         removeView(current);
  61         if (allViewsAreNeuterable || current->isNeuterable())
  62             current->neuter();
  63     }
  64
  65     m_isNeutered = true;
  66
  67     return true;
  68 }
  69
  70 bool ArrayBuffer::shareContentsWith(ArrayBufferContents& result)
  71 {
  72     ASSERT(isShared());
  73     RefPtr<ArrayBuffer> keepAlive(this);
  74
  75     if (!m_contents.data()) {
  76         result.neuter();
  77         return false;
  78     }
  79
  80     m_contents.shareWith(result);
  81     return true;
  82 }
  83
  84 void ArrayBuffer::addView(ArrayBufferView* view)
  85 {
  86     view->m_buffer = this;
  87     view->m_prevView = 0;
  88     view->m_nextView = m_firstView;
  89     if (m_firstView)
  90         m_firstView->m_prevView = view;
  91     m_firstView = view;
  92 }
  93
  94 void ArrayBuffer::removeView(ArrayBufferView* view)
  95 {
  96     ASSERT(this == view->m_buffer);
  97     if (view->m_nextView)
  98         view->m_nextView->m_prevView = view->m_prevView;
  99     if (view->m_prevView)
 100         view->m_prevView->m_nextView = view->m_nextView;
 101     if (m_firstView == view)
 102         m_firstView = view->m_nextView;
 103     view->m_prevView = view->m_nextView = 0;
 104 }
 105
 106 }