Imported WebKit commit 2ea9d364d0f6efa8fa64acf19f451504c59be0e4 (http://svn.webkit.org/repository/webkit/trunk@104285)

1 files changed, 220 insertions, 0 deletions

diff --git a/Source/JavaScriptCore/wtf/ArrayBuffer.h b/Source/JavaScriptCore/wtf/ArrayBuffer.h
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+++ b/Source/JavaScriptCore/wtf/ArrayBuffer.h
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+/*
+ * Copyright (C) 2009 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
+ */
+
+#ifndef ArrayBuffer_h
+#define ArrayBuffer_h
+
+#include <wtf/HashSet.h>
+#include <wtf/PassRefPtr.h>
+#include <wtf/RefCounted.h>
+#include <wtf/Vector.h>
+
+namespace WTF {
+
+class ArrayBuffer;
+class ArrayBufferView;
+
+class ArrayBufferContents {
+    WTF_MAKE_NONCOPYABLE(ArrayBufferContents);
+public:
+    ArrayBufferContents() 
+        : m_data(0)
+        , m_sizeInBytes(0)
+    { }
+
+    inline ~ArrayBufferContents();
+
+    void* data() { return m_data; }
+    unsigned sizeInBytes() { return m_sizeInBytes; }
+
+private:
+    ArrayBufferContents(void* data, unsigned sizeInBytes) 
+        : m_data(data)
+        , m_sizeInBytes(sizeInBytes)
+    { }
+
+    friend class ArrayBuffer;
+
+    static inline void tryAllocate(unsigned numElements, unsigned elementByteSize, ArrayBufferContents&);
+    void transfer(ArrayBufferContents& other)
+    {
+        ASSERT(!other.m_data);
+        other.m_data = m_data;
+        other.m_sizeInBytes = m_sizeInBytes;
+        m_data = 0;
+        m_sizeInBytes = 0;
+    }
+
+    void* m_data;
+    unsigned m_sizeInBytes;
+};
+
+class ArrayBuffer : public RefCounted<ArrayBuffer> {
+public:
+    static inline PassRefPtr<ArrayBuffer> create(unsigned numElements, unsigned elementByteSize);
+    static inline PassRefPtr<ArrayBuffer> create(ArrayBuffer*);
+    static inline PassRefPtr<ArrayBuffer> create(const void* source, unsigned byteLength);
+    static inline PassRefPtr<ArrayBuffer> create(ArrayBufferContents&);
+
+    inline void* data();
+    inline const void* data() const;
+    inline unsigned byteLength() const;
+
+    inline PassRefPtr<ArrayBuffer> slice(int begin, int end) const;
+    inline PassRefPtr<ArrayBuffer> slice(int begin) const;
+
+    void addView(ArrayBufferView*);
+    void removeView(ArrayBufferView*);
+
+    bool transfer(ArrayBufferContents&, Vector<RefPtr<ArrayBufferView> >& neuteredViews);
+    bool isNeutered() { return !m_contents.m_data; }
+
+    ~ArrayBuffer() { }
+
+private:
+    inline ArrayBuffer(ArrayBufferContents&);
+    inline PassRefPtr<ArrayBuffer> sliceImpl(unsigned begin, unsigned end) const;
+    inline unsigned clampIndex(int index) const;
+    static inline int clampValue(int x, int left, int right);
+
+    ArrayBufferContents m_contents;
+    ArrayBufferView* m_firstView;
+};
+
+int ArrayBuffer::clampValue(int x, int left, int right)
+{
+    ASSERT(left <= right);
+    if (x < left)
+        x = left;
+    if (right < x)
+        x = right;
+    return x;
+}
+
+PassRefPtr<ArrayBuffer> ArrayBuffer::create(unsigned numElements, unsigned elementByteSize)
+{
+    ArrayBufferContents contents;
+    ArrayBufferContents::tryAllocate(numElements, elementByteSize, contents);
+    if (!contents.m_data)
+        return 0;
+    return adoptRef(new ArrayBuffer(contents));
+}
+
+PassRefPtr<ArrayBuffer> ArrayBuffer::create(ArrayBuffer* other)
+{
+    return ArrayBuffer::create(other->data(), other->byteLength());
+}
+
+PassRefPtr<ArrayBuffer> ArrayBuffer::create(const void* source, unsigned byteLength)
+{
+    ArrayBufferContents contents;
+    ArrayBufferContents::tryAllocate(byteLength, 1, contents);
+    if (!contents.m_data)
+        return 0;
+    RefPtr<ArrayBuffer> buffer = adoptRef(new ArrayBuffer(contents));
+    memcpy(buffer->data(), source, byteLength);
+    return buffer.release();
+}
+
+PassRefPtr<ArrayBuffer> ArrayBuffer::create(ArrayBufferContents& contents)
+{
+    return adoptRef(new ArrayBuffer(contents));
+}
+
+ArrayBuffer::ArrayBuffer(ArrayBufferContents& contents)
+    : m_firstView(0)
+{
+    contents.transfer(m_contents);
+}
+
+void* ArrayBuffer::data()
+{
+    return m_contents.m_data;
+}
+
+const void* ArrayBuffer::data() const
+{
+    return m_contents.m_data;
+}
+
+unsigned ArrayBuffer::byteLength() const
+{
+    return m_contents.m_sizeInBytes;
+}
+
+PassRefPtr<ArrayBuffer> ArrayBuffer::slice(int begin, int end) const
+{
+    return sliceImpl(clampIndex(begin), clampIndex(end));
+}
+
+PassRefPtr<ArrayBuffer> ArrayBuffer::slice(int begin) const
+{
+    return sliceImpl(clampIndex(begin), byteLength());
+}
+
+PassRefPtr<ArrayBuffer> ArrayBuffer::sliceImpl(unsigned begin, unsigned end) const
+{
+    unsigned size = begin <= end ? end - begin : 0;
+    return ArrayBuffer::create(static_cast<const char*>(data()) + begin, size);
+}
+
+unsigned ArrayBuffer::clampIndex(int index) const
+{
+    unsigned currentLength = byteLength();
+    if (index < 0)
+        index = currentLength + index;
+    return clampValue(index, 0, currentLength);
+}
+
+void ArrayBufferContents::tryAllocate(unsigned numElements, unsigned elementByteSize, ArrayBufferContents& result)
+{
+    // Do not allow 32-bit overflow of the total size.
+    // FIXME: Why not? The tryFastCalloc function already checks its arguments,
+    // and will fail if there is any overflow, so why should we include a
+    // redudant unnecessarily restrictive check here?
+    if (numElements) {
+        unsigned totalSize = numElements * elementByteSize;
+        if (totalSize / numElements != elementByteSize) {
+            result.m_data = 0;
+            return;
+        }
+    }
+    if (WTF::tryFastCalloc(numElements, elementByteSize).getValue(result.m_data)) {
+        result.m_sizeInBytes = numElements * elementByteSize;
+        return;
+    }
+    result.m_data = 0;
+}
+
+ArrayBufferContents::~ArrayBufferContents()
+{
+    WTF::fastFree(m_data);
+}
+
+} // namespace WTF
+
+using WTF::ArrayBuffer;
+
+#endif // ArrayBuffer_h