1 files changed, 133 insertions, 0 deletions
diff --git a/Source/WTF/wtf/persistence/Decoder.cpp b/Source/WTF/wtf/persistence/Decoder.cpp
new file mode 100644
index 000000000..354ff0606
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+++ b/Source/WTF/wtf/persistence/Decoder.cpp
@@ -0,0 +1,133 @@
+/*
+ * Copyright (C) 2010, 2011, 2014 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 INC. 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 INC. 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"
+#include "Decoder.h"
+
+#include <wtf/persistence/Encoder.h>
+
+namespace WTF {
+namespace Persistence {
+
+Decoder::Decoder(const uint8_t* buffer, size_t bufferSize)
+    : m_buffer(buffer)
+    , m_bufferPosition(buffer)
+    , m_bufferEnd(buffer + bufferSize)
+{
+}
+
+Decoder::~Decoder()
+{
+}
+
+bool Decoder::bufferIsLargeEnoughToContain(size_t size) const
+{
+    return size <= static_cast<size_t>(m_bufferEnd - m_bufferPosition);
+}
+
+bool Decoder::decodeFixedLengthData(uint8_t* data, size_t size)
+{
+    if (!bufferIsLargeEnoughToContain(size))
+        return false;
+
+    memcpy(data, m_bufferPosition, size);
+    m_bufferPosition += size;
+
+    Encoder::updateChecksumForData(m_sha1, data, size);
+    return true;
+}
+
+template<typename Type>
+bool Decoder::decodeNumber(Type& value)
+{
+    if (!bufferIsLargeEnoughToContain(sizeof(value)))
+        return false;
+
+    memcpy(&value, m_bufferPosition, sizeof(value));
+    m_bufferPosition += sizeof(Type);
+
+    Encoder::updateChecksumForNumber(m_sha1, value);
+    return true;
+}
+
+bool Decoder::decode(bool& result)
+{
+    return decodeNumber(result);
+}
+
+bool Decoder::decode(uint8_t& result)
+{
+    return decodeNumber(result);
+}
+
+bool Decoder::decode(uint16_t& result)
+{
+    return decodeNumber(result);
+}
+
+bool Decoder::decode(uint32_t& result)
+{
+    return decodeNumber(result);
+}
+
+bool Decoder::decode(uint64_t& result)
+{
+    return decodeNumber(result);
+}
+
+bool Decoder::decode(int32_t& result)
+{
+    return decodeNumber(result);
+}
+
+bool Decoder::decode(int64_t& result)
+{
+    return decodeNumber(result);
+}
+
+bool Decoder::decode(float& result)
+{
+    return decodeNumber(result);
+}
+
+bool Decoder::decode(double& result)
+{
+    return decodeNumber(result);
+}
+
+bool Decoder::verifyChecksum()
+{
+    SHA1::Digest computedHash;
+    m_sha1.computeHash(computedHash);
+
+    SHA1::Digest savedHash;
+    if (!decodeFixedLengthData(savedHash.data(), sizeof(savedHash)))
+        return false;
+
+    return computedHash == savedHash;
+}
+
+}
+}