Merge WebKit at r75315: Initial merge by git.

Change-Id: I570314b346ce101c935ed22a626b48c2af266b84

1 files changed, 235 insertions, 0 deletions

diff --git a/Source/WebCore/html/canvas/DataView.cpp b/Source/WebCore/html/canvas/DataView.cpp
new file mode 100755
index 0000000..82b10b3
--- /dev/null
+++ b/Source/WebCore/html/canvas/DataView.cpp
@@ -0,0 +1,235 @@
+/*
+ * Copyright (C) 2010 Google 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 AND ITS CONTRIBUTORS "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 OR ITS 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.
+ */
+
+#include "config.h"
+
+#if ENABLE(3D_CANVAS) || ENABLE(BLOB)
+
+#include "DataView.h"
+
+#include "CheckedInt.h"
+
+namespace {
+
+template<typename T>
+union Value {
+    T data;
+    char bytes[sizeof(T)];
+};
+
+}
+
+namespace WebCore {
+
+PassRefPtr<DataView> DataView::create(PassRefPtr<ArrayBuffer> buffer, unsigned byteOffset, unsigned byteLength)
+{
+    if (byteOffset > buffer->byteLength())
+        return 0;
+    CheckedInt<uint32_t> checkedOffset(byteOffset);
+    CheckedInt<uint32_t> checkedLength(byteLength);
+    CheckedInt<uint32_t> checkedMax = checkedOffset + checkedLength;
+    if (!checkedMax.valid() || checkedMax.value() > buffer->byteLength())
+        return 0;
+    return adoptRef(new DataView(buffer, byteOffset, byteLength));
+}
+
+DataView::DataView(PassRefPtr<ArrayBuffer> buffer, unsigned byteOffset, unsigned byteLength)
+    : ArrayBufferView(buffer, byteOffset)
+    , m_byteLength(byteLength)
+{
+}
+
+static bool needToFlipBytes(bool littleEndian)
+{
+#if CPU(BIG_ENDIAN)
+    return littleEndian;
+#else
+    return !littleEndian;
+#endif
+}
+
+inline void swapBytes(char* p, char* q)
+{
+    char temp = *p;
+    *p = *q;
+    *q = temp;
+}
+
+static void flipBytesFor16Bits(char* p)
+{
+    swapBytes(p, p + 1);
+}
+
+static void flipBytesFor32Bits(char* p)
+{
+    swapBytes(p, p + 3);
+    swapBytes(p + 1, p + 2);
+}
+
+static void flipBytesFor64Bits(char* p)
+{
+    swapBytes(p, p + 7);
+    swapBytes(p + 1, p + 6);
+    swapBytes(p + 2, p + 5);
+    swapBytes(p + 3, p + 4);
+}
+
+static void flipBytesIfNeeded(char* value, size_t size, bool littleEndian)
+{
+    if (!needToFlipBytes(littleEndian))
+        return;
+
+    switch (size) {
+    case 1:
+        // Nothing to do.
+        break;
+    case 2:
+        flipBytesFor16Bits(value);
+        break;
+    case 4:
+        flipBytesFor32Bits(value);
+        break;
+    case 8:
+        flipBytesFor64Bits(value);
+        break;
+    default:
+        ASSERT_NOT_REACHED();
+        break;
+    }
+}
+
+template<typename T>
+T DataView::getData(unsigned byteOffset, bool littleEndian, ExceptionCode& ec) const
+{
+    if (beyondRange<T>(byteOffset)) {
+        ec = INDEX_SIZE_ERR;
+        return 0;
+    }
+
+    // We do not want to load the data directly since it would cause a bus error on architectures that don't support unaligned loads.
+    Value<T> value;
+    memcpy(value.bytes, static_cast<const char*>(m_baseAddress) + byteOffset, sizeof(T));
+    flipBytesIfNeeded(value.bytes, sizeof(T), littleEndian);
+    return value.data;
+}
+
+template<typename T>
+void DataView::setData(unsigned byteOffset, T value, bool littleEndian, ExceptionCode& ec)
+{
+    if (beyondRange<T>(byteOffset)) {
+        ec = INDEX_SIZE_ERR;
+        return;
+    }
+
+    // We do not want to store the data directly since it would cause a bus error on architectures that don't support unaligned stores.
+    Value<T> tempValue;
+    tempValue.data = value;
+    flipBytesIfNeeded(tempValue.bytes, sizeof(T), littleEndian);
+    memcpy(static_cast<char*>(m_baseAddress) + byteOffset, tempValue.bytes, sizeof(T));
+}
+
+int8_t DataView::getInt8(unsigned byteOffset, ExceptionCode& ec)
+{
+    return getData<int8_t>(byteOffset, false, ec);
+}
+
+uint8_t DataView::getUint8(unsigned byteOffset, ExceptionCode& ec)
+{
+    return getData<uint8_t>(byteOffset, false, ec);
+}
+
+int16_t DataView::getInt16(unsigned byteOffset, bool littleEndian, ExceptionCode& ec)
+{
+    return getData<int16_t>(byteOffset, littleEndian, ec);
+}
+
+uint16_t DataView::getUint16(unsigned byteOffset, bool littleEndian, ExceptionCode& ec)
+{
+    return getData<uint16_t>(byteOffset, littleEndian, ec);
+}
+
+int32_t DataView::getInt32(unsigned byteOffset, bool littleEndian, ExceptionCode& ec)
+{
+    return getData<int32_t>(byteOffset, littleEndian, ec);
+}
+
+uint32_t DataView::getUint32(unsigned byteOffset, bool littleEndian, ExceptionCode& ec)
+{
+    return getData<uint32_t>(byteOffset, littleEndian, ec);
+}
+
+float DataView::getFloat32(unsigned byteOffset, bool littleEndian, ExceptionCode& ec)
+{
+    return getData<float>(byteOffset, littleEndian, ec);
+}
+
+double DataView::getFloat64(unsigned byteOffset, bool littleEndian, ExceptionCode& ec)
+{
+    return getData<double>(byteOffset, littleEndian, ec);
+}
+
+void DataView::setInt8(unsigned byteOffset, int8_t value, ExceptionCode& ec)
+{
+    setData<int8_t>(byteOffset, value, false, ec);
+}
+
+void DataView::setUint8(unsigned byteOffset, uint8_t value, ExceptionCode& ec)
+{
+    setData<uint8_t>(byteOffset, value, false, ec);
+}
+
+void DataView::setInt16(unsigned byteOffset, short value, bool littleEndian, ExceptionCode& ec)
+{
+    setData<int16_t>(byteOffset, value, littleEndian, ec);
+}
+
+void DataView::setUint16(unsigned byteOffset, uint16_t value, bool littleEndian, ExceptionCode& ec)
+{
+    setData<uint16_t>(byteOffset, value, littleEndian, ec);
+}
+
+void DataView::setInt32(unsigned byteOffset, int32_t value, bool littleEndian, ExceptionCode& ec)
+{
+    setData<int32_t>(byteOffset, value, littleEndian, ec);
+}
+
+void DataView::setUint32(unsigned byteOffset, uint32_t value, bool littleEndian, ExceptionCode& ec)
+{
+    setData<uint32_t>(byteOffset, value, littleEndian, ec);
+}
+
+void DataView::setFloat32(unsigned byteOffset, float value, bool littleEndian, ExceptionCode& ec)
+{
+    setData<float>(byteOffset, value, littleEndian, ec);
+}
+
+void DataView::setFloat64(unsigned byteOffset, double value, bool littleEndian, ExceptionCode& ec)
+{
+    setData<double>(byteOffset, value, littleEndian, ec);
+}
+
+}
+
+#endif // ENABLE(3D_CANVAS) || ENABLE(BLOB)