AuxData.hpp

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//===- AuxData.hpp -----------------------------------------------*- C++-*-===//
//
//  Copyright (C) 2020 GrammaTech, Inc.
//
//  This code is licensed under the MIT license. See the LICENSE file in the
//  project root for license terms.
//
//  This project is sponsored by the Office of Naval Research, One Liberty
//  Center, 875 N. Randolph Street, Arlington, VA 22203 under contract #
//  N68335-17-C-0700.  The content of the information does not necessarily
//  reflect the position or policy of the Government and no official
//  endorsement should be inferred.
//
//===----------------------------------------------------------------------===//
#ifndef GTIRB_AUXDATA_H
#define GTIRB_AUXDATA_H
 
#include <gtirb/Addr.hpp>
#include <gtirb/Node.hpp>
#include <gtirb/Offset.hpp>
#include <boost/endian/conversion.hpp>
#include <deque>
#include <iostream>
#include <list>
#include <map>
#include <set>
#include <string>
#include <type_traits>
#include <typeinfo>
#include <unordered_map>
#include <variant>
#include <vector>
 
 
namespace gtirb {
namespace proto {
class AuxData;
} // namespace proto
class Context;
 
 
 
template <class T> struct is_sequence : std::false_type {};
 
template <class T> struct is_sequence<std::vector<T>> : std::true_type {};
template <class T> struct is_sequence<std::list<T>> : std::true_type {};
template <class T> struct is_sequence<std::deque<T>> : std::true_type {};
 
template <class T> struct is_mapping : std::false_type {};
template <class T, class U>
struct is_mapping<std::map<T, U>> : std::true_type {};
template <class T, class U>
struct is_mapping<std::unordered_map<T, U>> : std::true_type {};
// Explicitly disable multimaps. Because they can contain multiple values for
// a given key, they can't be used interchangeably with maps.
template <class T, class U>
struct is_mapping<std::multimap<T, U>> : std::false_type {};
template <class T, class U>
struct is_mapping<std::unordered_multimap<T, U>> : std::false_type {};
 
template <class T> struct is_tuple : std::false_type {};
template <class... Args>
struct is_tuple<std::tuple<Args...>> : std::true_type {};
 
template <class... Args>
struct is_tuple<std::pair<Args...>> : std::true_type {};
 
// Utility class for serializing AuxData.
class ToByteRange {
public:
  explicit ToByteRange(std::string& Bytes) : It(std::back_inserter(Bytes)) {}
 
  void write(std::byte Byte) { *It = static_cast<char>(Byte); }
 
private:
  std::back_insert_iterator<std::string> It;
};
 
// Utility class for deserializing AuxData.
class FromByteRange {
public:
  explicit FromByteRange(const std::string& Bytes)
      : Curr(Bytes.begin()), End(Bytes.end()) {}
 
  bool read(std::byte& Byte) {
    if (Curr == End)
      return false;
 
    Byte = std::byte(*Curr);
    ++Curr;
    return true;
  }
 
  uint64_t remainingBytesToRead() const {
    return static_cast<uint64_t>(std::distance(Curr, End));
  }
 
private:
  std::string::const_iterator Curr;
  std::string::const_iterator End;
};
 
 
template <class T, class Enable = void> struct auxdata_traits {
  static void toBytes(const T& Object, ToByteRange& TBR) = delete;
 
  static bool fromBytes(T& Object, FromByteRange& FBR) = delete;
 
  static std::string type_name() = delete;
};
 
template <class... Ts> struct TypeId {};
 
template <class T>
struct is_endian_type
    : std::integral_constant<bool, std::is_class_v<T> ||
                                       (std::is_integral_v<T> &&
                                        !std::is_same_v<T, bool>)> {};
 
template <typename T, typename Enable = void> struct default_serialization {};
 
// Serialize and deserialize by copying the object representation directly.
template <typename T>
struct default_serialization<
    T, typename std::enable_if_t<is_endian_type<T>::value ||
                                 std::is_floating_point<T>::value ||
                                 std::is_same<T, bool>::value>> {
  static void toBytes(const T& object, ToByteRange& TBR) {
    // Store as little-endian.
    T ordered = object;
 
    if constexpr (!std::is_floating_point<T>::value &&
                  !std::is_same<T, bool>::value) {
      // Do not reorder floating point or boolean values
      boost::endian::conditional_reverse_inplace<boost::endian::order::little,
                                                 boost::endian::order::native>(
          ordered);
    }
    auto srcBytes_begin = reinterpret_cast<const std::byte*>(&ordered);
    auto srcBytes_end = reinterpret_cast<const std::byte*>(&ordered + 1);
    std::for_each(srcBytes_begin, srcBytes_end, [&](auto b) { TBR.write(b); });
  }
 
  static bool fromBytes(T& object, FromByteRange& FBR) {
    auto dest_begin = reinterpret_cast<std::byte*>(&object);
    auto dest_end = reinterpret_cast<std::byte*>(&object + 1);
    bool Success = true;
    std::for_each(dest_begin, dest_end, [&](auto& b) {
      if (!FBR.read(b))
        Success = false;
    });
    if (!Success) {
      return false;
    }
 
    // Data stored as little-endian.
    if constexpr (!std::is_floating_point<T>::value &&
                  !std::is_same<T, bool>::value) {
      boost::endian::conditional_reverse_inplace<boost::endian::order::little,
                                                 boost::endian::order::native>(
          object);
    }
 
    return true;
  }
};
 
template <>
struct auxdata_traits<std::byte> : default_serialization<std::byte> {
  static std::string type_name() { return "byte"; }
 
  static void toBytes(std::byte object, ToByteRange& TBR) { TBR.write(object); }
 
  static bool fromBytes(std::byte& object, FromByteRange& FBR) {
    return FBR.read(object);
  }
};
 
template <> struct auxdata_traits<Addr> : default_serialization<Addr> {
  static std::string type_name() { return "Addr"; }
};
 
template <> struct auxdata_traits<UUID> : default_serialization<UUID> {
  static std::string type_name() { return "UUID"; }
};
 
template <class T>
struct auxdata_traits<T, typename std::enable_if_t<std::is_integral<T>::value &&
                                                   std::is_signed<T>::value>>
    : default_serialization<T> {
  static std::string type_name() {
    return "int" + std::to_string(8 * sizeof(T)) + "_t";
  }
};
 
template <class T>
struct auxdata_traits<T, typename std::enable_if_t<std::is_integral<T>::value &&
                                                   std::is_unsigned<T>::value>>
    : default_serialization<T> {
  static std::string type_name() {
    return "uint" + std::to_string(8 * sizeof(T)) + "_t";
  }
};
 
template <> struct auxdata_traits<bool> : default_serialization<bool> {
  static std::string type_name() { return "bool"; }
};
 
template <> struct auxdata_traits<float> : default_serialization<float> {
  static std::string type_name() { return "float"; }
};
 
template <> struct auxdata_traits<double> : default_serialization<double> {
  static std::string type_name() { return "double"; }
};
 
template <> struct auxdata_traits<std::string> {
  static std::string type_name() { return "string"; }
 
  static void toBytes(const std::string& Object, ToByteRange& TBR) {
    auxdata_traits<uint64_t>::toBytes(Object.size(), TBR);
    std::for_each(Object.begin(), Object.end(),
                  [&](auto& elt) { auxdata_traits<char>::toBytes(elt, TBR); });
  }
 
  static bool fromBytes(std::string& Object, FromByteRange& FBR) {
    uint64_t Count;
    if (!auxdata_traits<uint64_t>::fromBytes(Count, FBR))
      return false;
 
    if (Count > FBR.remainingBytesToRead())
      return false;
 
    Object.resize(Count);
    bool Success = true;
    std::for_each(Object.begin(), Object.end(), [&](auto& elt) {
      if (!auxdata_traits<char>::fromBytes(elt, FBR))
        Success = false;
    });
 
    return Success;
  }
};
 
template <> struct auxdata_traits<Offset> {
  static std::string type_name() { return "Offset"; }
 
  static void toBytes(const Offset& Object, ToByteRange& TBR) {
    auxdata_traits<UUID>::toBytes(Object.ElementId, TBR);
    auxdata_traits<uint64_t>::toBytes(Object.Displacement, TBR);
  }
 
  static bool fromBytes(Offset& Object, FromByteRange& FBR) {
    if (!auxdata_traits<UUID>::fromBytes(Object.ElementId, FBR))
      return false;
    return auxdata_traits<uint64_t>::fromBytes(Object.Displacement, FBR);
  }
};
 
template <class T>
struct auxdata_traits<T, typename std::enable_if_t<is_sequence<T>::value>> {
  static std::string type_name() {
    return "sequence<" + TypeId<typename T::value_type>::value() + ">";
  }
 
  static void toBytes(const T& Object, ToByteRange& TBR) {
    auxdata_traits<uint64_t>::toBytes(Object.size(), TBR);
    std::for_each(Object.begin(), Object.end(), [&](const auto& Elt) {
      auxdata_traits<typename T::value_type>::toBytes(Elt, TBR);
    });
  }
 
  static bool fromBytes(T& Object, FromByteRange& FBR) {
    uint64_t Count;
    if (!auxdata_traits<uint64_t>::fromBytes(Count, FBR))
      return false;
 
    if (Count > FBR.remainingBytesToRead())
      return false;
 
    Object.resize(Count);
    bool Success = true;
    std::for_each(Object.begin(), Object.end(), [&](auto& Elt) {
      if (!auxdata_traits<typename T::value_type>::fromBytes(Elt, FBR))
        Success = false;
    });
 
    return Success;
  }
};
 
template <class... Args> struct auxdata_traits<std::set<Args...>> {
  using T = std::set<Args...>;
 
  static std::string type_name() {
    return "set<" + TypeId<typename T::value_type>::value() + ">";
  }
 
  static void toBytes(const T& Object, ToByteRange& TBR) {
    auxdata_traits<uint64_t>::toBytes(Object.size(), TBR);
    for (const auto& Elt : Object)
      auxdata_traits<typename T::value_type>::toBytes(Elt, TBR);
  }
 
  static bool fromBytes(T& Object, FromByteRange& FBR) {
    uint64_t Count;
    if (!auxdata_traits<uint64_t>::fromBytes(Count, FBR))
      return false;
 
    if (Count > FBR.remainingBytesToRead())
      return false;
 
    for (uint64_t i = 0; i < Count; i++) {
      typename T::value_type V;
      if (!auxdata_traits<decltype(V)>::fromBytes(V, FBR))
        return false;
      Object.emplace(std::move(V));
    }
 
    return true;
  }
};
 
template <class T>
struct auxdata_traits<T, typename std::enable_if_t<is_mapping<T>::value>> {
  static std::string type_name() {
    return "mapping<" +
           TypeId<typename T::key_type, typename T::mapped_type>::value() + ">";
  }
 
  static void toBytes(const T& Object, ToByteRange& TBR) {
    auxdata_traits<uint64_t>::toBytes(Object.size(), TBR);
    std::for_each(Object.begin(), Object.end(), [&](const auto& Elt) {
      auxdata_traits<typename T::key_type>::toBytes(Elt.first, TBR);
      auxdata_traits<typename T::mapped_type>::toBytes(Elt.second, TBR);
    });
  }
 
  static bool fromBytes(T& Object, FromByteRange& FBR) {
    uint64_t Count;
    if (!auxdata_traits<uint64_t>::fromBytes(Count, FBR))
      return false;
 
    if (Count > FBR.remainingBytesToRead())
      return false;
 
    for (uint64_t i = 0; i < Count; i++) {
      typename T::key_type K;
      if (!auxdata_traits<decltype(K)>::fromBytes(K, FBR))
        return false;
      typename T::mapped_type V;
      if (!auxdata_traits<decltype(V)>::fromBytes(V, FBR))
        return false;
      Object.emplace(std::move(K), std::move(V));
    }
    return true;
  }
};
 
template <class... Args> struct auxdata_traits<std::variant<Args...>> {
  using T = std::variant<Args...>;
 
  static std::string type_name() {
    return "variant<" + TypeId<Args...>::value() + ">";
  }
 
  template <uint64_t I = 0>
  static std::optional<std::variant<Args...>> expand_type(uint64_t i) {
    if constexpr (I >= sizeof...(Args)) {
      return std::nullopt;
    } else {
      return i == 0 ? std::variant<Args...>{std::in_place_index<I>,
                                            std::variant_alternative_t<I, T>{}}
                    : expand_type<I + 1>(i - 1);
    }
  };
 
  static void toBytes(const T& Object, ToByteRange& TBR) {
    uint64_t Index = Object.index();
    auxdata_traits<uint64_t>::toBytes(Index, TBR);
    std::visit(
        [TBR](auto&& arg) mutable {
          auxdata_traits<typename std::remove_const<
              typename std::remove_reference<decltype(arg)>::type>::type>::
              toBytes(arg, TBR);
        },
        Object);
  }
 
  static bool fromBytes(T& Object, FromByteRange& FBR) {
    uint64_t Index;
    if (!auxdata_traits<uint64_t>::fromBytes(Index, FBR))
      return false;
    if (Index > FBR.remainingBytesToRead())
      return false;
 
    auto maybeV = expand_type(Index);
    if (!maybeV) {
      return false;
    }
    auto V = *maybeV;
    bool res_code = false;
    std::visit(
        [&res_code, &FBR](auto&& arg) mutable {
          typename std::remove_reference<decltype(arg)>::type Val;
          res_code = auxdata_traits<typename std::remove_reference<decltype(
              arg)>::type>::fromBytes(Val, FBR);
          if (!res_code)
            return;
          arg = Val;
        },
        V);
    if (!res_code)
      return false;
    Object = V;
    return true;
  }
};
 
template <class T> struct tuple_traits {};
template <class... Ts> struct tuple_traits<std::tuple<Ts...>> {
  using Tuple = std::tuple<Ts...>;
 
  static std::string type_name() {
    return "tuple<" + TypeId<Ts...>::value() + ">";
  }
};
 
template <class... Ts> struct tuple_traits<std::pair<Ts...>> {
  using Tuple = std::tuple<Ts...>;
 
  static std::string type_name() {
    return "tuple<" + TypeId<Ts...>::value() + ">";
  }
};
 
template <class Func, size_t... Is>
constexpr void static_for(Func&& f, std::integer_sequence<size_t, Is...>) {
  (f(std::integral_constant<size_t, Is>{}), ...);
}
 
template <class T>
struct auxdata_traits<T, typename std::enable_if_t<is_tuple<T>::value>>
    : tuple_traits<T> {
  static void toBytes(const T& Object, ToByteRange& TBR) {
    static_for(
        [&](auto i) {
          const auto& F = std::get<i>(Object);
          auxdata_traits<std::remove_cv_t<
              std::remove_reference_t<decltype(F)>>>::toBytes(F, TBR);
        },
        std::make_index_sequence<std::tuple_size<T>::value>{});
  }
 
  static bool fromBytes(T& Object, FromByteRange& FBR) {
    bool Success = true;
    static_for(
        [&](auto i) {
          auto& F = std::get<i>(Object);
          if (!auxdata_traits<std::remove_cv_t<
                  std::remove_reference_t<decltype(F)>>>::fromBytes(F, FBR))
            Success = false;
        },
        std::make_index_sequence<std::tuple_size<T>::value>{});
 
    return Success;
  }
};
 
template <class T> struct TypeId<T> {
  static std::string value() { return auxdata_traits<T>::type_name(); }
};
 
template <class T, class... Ts> struct TypeId<T, Ts...> {
  static std::string value() {
    return auxdata_traits<T>::type_name() + "," + TypeId<Ts...>::value();
  }
};
 
class GTIRB_EXPORT_API AuxData {
public:
  struct SerializedForm {
    std::string RawBytes;
    std::string ProtobufType;
  };
 
  AuxData() = default;
 
  virtual ~AuxData() = default;
 
  const SerializedForm& rawData() const { return this->SF; }
 
  static constexpr std::size_t UNREGISTERED_API_TYPE_ID = 0;
 
  virtual std::size_t getApiTypeId() const { return UNREGISTERED_API_TYPE_ID; }
 
protected:
  using MessageType = proto::AuxData;
 
  static void fromProtobuf(AuxData& Result, const MessageType& Message);
 
  virtual void toProtobuf(MessageType* Message) const {
    toProtobuf(Message, this->SF);
  }
 
  // This version of protobuf accepts a SerializedForm object to
  // serialize rather than serializing AuxData's SerializedForm
  // member. This is used by AuxDataImpl to serialize a typed AuxData
  // object. We structure it this way to avoid having the AuxDataImpl
  // template (which is instantiated in client code) access
  // MessageType fields directly, which would introduce
  // dllimport/dllexport issues on Windows.
  void toProtobuf(MessageType* Message,
                  const SerializedForm& SFToSerialize) const;
 
  // Utility function for the AuxDataImpl template that allows us to
  // check the embedded type name in the serialized protobuf against an
  // expected typename without exposing the MessageType to clients.
  static bool checkAuxDataMessageType(const AuxData::MessageType& Message,
                                      const std::string& ExpectedName);
 
  // Present for testing purposes only.
  void save(std::ostream& Out) const;
 
  // Present for testing purposes only.
  static std::unique_ptr<AuxData>
  load(std::istream& In, std::unique_ptr<AuxData> (*FPPtr)(const MessageType&));
 
private:
  SerializedForm SF;
 
  friend class AuxDataContainer; // Friend to enable fromProtobuf.
  // Enables serialization by AuxDataContainer via containerToProtobuf.
  template <typename T> friend typename T::MessageType toProtobuf(const T&);
  friend class SerializationTestHarness; // Testing support.
};
 
template <class Schema> class AuxDataImpl : public AuxData {
public:
  AuxDataImpl() = default;
  AuxDataImpl(typename Schema::Type&& Val) : Object(std::move(Val)){};
 
  static std::size_t staticGetApiTypeId() {
    return typeid(typename Schema::Type).hash_code();
  }
 
  virtual std::size_t getApiTypeId() const override {
    return staticGetApiTypeId();
  }
 
  const typename Schema::Type* get() const { return &Object; }
 
private:
  static std::unique_ptr<AuxData> fromProtobuf(const MessageType& Message) {
    // Check if the serialized type isn't compatible with the type
    // we're trying to deserialize to.
    if (!checkAuxDataMessageType(
            Message, auxdata_traits<typename Schema::Type>::type_name())) {
      return nullptr;
    }
 
    // Note: Do not access Message's contents here. That would introduce
    // dllexport/dllimport problems on Windows. Call the base class's
    // fromProtobuf function and then unserialize from its
    // SerializedForm structure.
    auto TypedAuxData = std::make_unique<AuxDataImpl<Schema>>();
    AuxData::fromProtobuf(*TypedAuxData, Message);
    FromByteRange FBR(TypedAuxData->rawData().RawBytes);
    if (!auxdata_traits<typename Schema::Type>::fromBytes(TypedAuxData->Object,
                                                          FBR))
      return nullptr;
    return TypedAuxData;
  }
 
  virtual void toProtobuf(MessageType* Message) const override {
    // Note: Do not edit Message's contents here. That would introduce
    // dllexport/dllimport problems on Windows. Store to a
    // SerializedForm, and then call the base class's toProtobuf
    // function.
    AuxData::SerializedForm TypedSF;
    TypedSF.ProtobufType = auxdata_traits<typename Schema::Type>::type_name();
    ToByteRange TBR(TypedSF.RawBytes);
    auxdata_traits<typename Schema::Type>::toBytes(this->Object, TBR);
    AuxData::toProtobuf(Message, TypedSF);
  }
 
  // Present for testing purposes only.
  void save(std::ostream& Out) const { AuxData::save(Out); }
 
  // Present for testing purposes only.
  static std::unique_ptr<AuxDataImpl> load([[maybe_unused]] Context& C,
                                           std::istream& In) {
    return std::unique_ptr<AuxDataImpl>{
        static_cast<AuxDataImpl*>(AuxData::load(In, fromProtobuf).release())};
  }
 
  typename Schema::Type Object;
 
  friend class AuxDataContainer;         // Friend to enable to/fromProtobuf.
  friend class SerializationTestHarness; // Testing support.
};
 
// (end \defgroup AUXDATA_GROUP)
 
} // namespace gtirb
 
#endif // GTIRB_AUXDATA_H