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      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 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 ByteArray_h
     27 #define ByteArray_h
     28 
     29 #include <wtf/PassRefPtr.h>
     30 #include <wtf/RefCounted.h>
     31 
     32 namespace WTF {
     33     class ByteArray : public RefCountedBase {
     34     public:
     35         unsigned length() const { return m_size; }
     36 
     37         void set(unsigned index, double value)
     38         {
     39             if (index >= m_size)
     40                 return;
     41             if (!(value > 0)) // Clamp NaN to 0
     42                 value = 0;
     43             else if (value > 255)
     44                 value = 255;
     45             m_data[index] = static_cast<unsigned char>(value + 0.5);
     46         }
     47 
     48         void set(unsigned index, unsigned char value)
     49         {
     50             if (index >= m_size)
     51                 return;
     52             m_data[index] = value;
     53         }
     54 
     55         bool get(unsigned index, unsigned char& result) const
     56         {
     57             if (index >= m_size)
     58                 return false;
     59             result = m_data[index];
     60             return true;
     61         }
     62 
     63         unsigned char get(unsigned index) const
     64         {
     65             ASSERT(index < m_size);
     66             return m_data[index];
     67         }
     68 
     69         unsigned char* data() { return m_data; }
     70 
     71         void deref()
     72         {
     73             if (derefBase()) {
     74                 // We allocated with new unsigned char[] in create(),
     75                 // and then used placement new to construct the object.
     76                 this->~ByteArray();
     77                 delete[] reinterpret_cast<unsigned char*>(this);
     78             }
     79         }
     80 
     81         static PassRefPtr<ByteArray> create(size_t size);
     82 
     83     private:
     84         ByteArray(size_t size)
     85             : m_size(size)
     86         {
     87         }
     88         size_t m_size;
     89         unsigned char m_data[sizeof(size_t)];
     90     };
     91 }
     92 
     93 #endif
     94