| /* |
| * Copyright (C) 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. |
| */ |
| |
| #pragma once |
| |
| #include <wtf/EnumTraits.h> |
| #include <wtf/SHA1.h> |
| #include <wtf/persistence/PersistentCoder.h> |
| |
| namespace WTF { |
| namespace Persistence { |
| |
| class Decoder { |
| WTF_MAKE_FAST_ALLOCATED; |
| public: |
| WTF_EXPORT_PRIVATE Decoder(const uint8_t* buffer, size_t bufferSize); |
| WTF_EXPORT_PRIVATE ~Decoder(); |
| |
| size_t length() const { return m_bufferEnd - m_buffer; } |
| size_t currentOffset() const { return m_bufferPosition - m_buffer; } |
| |
| WTF_EXPORT_PRIVATE WARN_UNUSED_RETURN bool verifyChecksum(); |
| |
| WTF_EXPORT_PRIVATE WARN_UNUSED_RETURN bool decodeFixedLengthData(uint8_t*, size_t); |
| |
| WTF_EXPORT_PRIVATE Decoder& operator>>(Optional<bool>&); |
| WTF_EXPORT_PRIVATE Decoder& operator>>(Optional<uint8_t>&); |
| WTF_EXPORT_PRIVATE Decoder& operator>>(Optional<uint16_t>&); |
| WTF_EXPORT_PRIVATE Decoder& operator>>(Optional<uint32_t>&); |
| WTF_EXPORT_PRIVATE Decoder& operator>>(Optional<uint64_t>&); |
| WTF_EXPORT_PRIVATE Decoder& operator>>(Optional<int16_t>&); |
| WTF_EXPORT_PRIVATE Decoder& operator>>(Optional<int32_t>&); |
| WTF_EXPORT_PRIVATE Decoder& operator>>(Optional<int64_t>&); |
| WTF_EXPORT_PRIVATE Decoder& operator>>(Optional<float>&); |
| WTF_EXPORT_PRIVATE Decoder& operator>>(Optional<double>&); |
| |
| template<typename T, std::enable_if_t<!std::is_arithmetic<typename std::remove_const<T>>::value && !std::is_enum<T>::value>* = nullptr> |
| Decoder& operator>>(Optional<T>& result) |
| { |
| result = Coder<T>::decode(*this); |
| return *this; |
| } |
| |
| template<typename E, std::enable_if_t<std::is_enum<E>::value>* = nullptr> |
| Decoder& operator>>(Optional<E>& result) |
| { |
| static_assert(sizeof(E) <= 8, "Enum type T must not be larger than 64 bits!"); |
| Optional<uint64_t> value; |
| *this >> value; |
| if (!value) |
| return *this; |
| if (!isValidEnum<E>(*value)) |
| return *this; |
| result = static_cast<E>(*value); |
| return *this; |
| } |
| |
| template<typename T> WARN_UNUSED_RETURN |
| bool bufferIsLargeEnoughToContain(size_t numElements) const |
| { |
| static_assert(std::is_arithmetic<T>::value, "Type T must have a fixed, known encoded size!"); |
| |
| if (numElements > std::numeric_limits<size_t>::max() / sizeof(T)) |
| return false; |
| |
| return bufferIsLargeEnoughToContain(numElements * sizeof(T)); |
| } |
| |
| static constexpr bool isIPCDecoder = false; |
| |
| private: |
| WTF_EXPORT_PRIVATE WARN_UNUSED_RETURN bool bufferIsLargeEnoughToContain(size_t) const; |
| template<typename Type> Decoder& decodeNumber(Optional<Type>&); |
| |
| const uint8_t* m_buffer; |
| const uint8_t* m_bufferPosition; |
| const uint8_t* m_bufferEnd; |
| |
| SHA1 m_sha1; |
| }; |
| |
| } |
| } |
| |