v1.4.4

source/core/StarDataStream.hpp

@@ -0,0 +1,393 @@
+#ifndef STAR_DATA_STREAM_HPP
+#define STAR_DATA_STREAM_HPP
+
+#include "StarString.hpp"
+
+namespace Star {
+
+STAR_EXCEPTION(DataStreamException, IOException);
+
+// Writes complex types to bytes in a portable big-endian fashion.
+class DataStream {
+public:
+  DataStream();
+  virtual ~DataStream() = default;
+
+  static unsigned const CurrentStreamVersion = 1;
+
+  // DataStream defaults to big-endian order for all primitive types
+  ByteOrder byteOrder() const;
+  void setByteOrder(ByteOrder byteOrder);
+
+  // DataStream can optionally write strings as null terminated rather than
+  // length prefixed
+  bool nullTerminatedStrings() const;
+  void setNullTerminatedStrings(bool nullTerminatedStrings);
+
+  // streamCompatibilityVersion defaults to CurrentStreamVersion, but can be
+  // changed for compatibility with older versions of DataStream serialization.
+  unsigned streamCompatibilityVersion() const;
+  void setStreamCompatibilityVersion(unsigned streamCompatibilityVersion);
+
+  // Do direct reads and writes
+  virtual void readData(char* data, size_t len) = 0;
+  virtual void writeData(char const* data, size_t len) = 0;
+
+  // These do not read / write sizes, they simply read / write directly.
+  ByteArray readBytes(size_t len);
+  void writeBytes(ByteArray const& ba);
+
+  DataStream& operator<<(bool d);
+  DataStream& operator<<(char c);
+  DataStream& operator<<(int8_t d);
+  DataStream& operator<<(uint8_t d);
+  DataStream& operator<<(int16_t d);
+  DataStream& operator<<(uint16_t d);
+  DataStream& operator<<(int32_t d);
+  DataStream& operator<<(uint32_t d);
+  DataStream& operator<<(int64_t d);
+  DataStream& operator<<(uint64_t d);
+  DataStream& operator<<(float d);
+  DataStream& operator<<(double d);
+
+  DataStream& operator>>(bool& d);
+  DataStream& operator>>(char& c);
+  DataStream& operator>>(int8_t& d);
+  DataStream& operator>>(uint8_t& d);
+  DataStream& operator>>(int16_t& d);
+  DataStream& operator>>(uint16_t& d);
+  DataStream& operator>>(int32_t& d);
+  DataStream& operator>>(uint32_t& d);
+  DataStream& operator>>(int64_t& d);
+  DataStream& operator>>(uint64_t& d);
+  DataStream& operator>>(float& d);
+  DataStream& operator>>(double& d);
+
+  // Writes and reads a VLQ encoded integer.  Can write / read anywhere from 1
+  // to 10 bytes of data, with integers of smaller (absolute) value taking up
+  // fewer bytes.  size_t version can be used to portably write a size_t type,
+  // and portably and efficiently handles the case of NPos.
+
+  size_t writeVlqU(uint64_t i);
+  size_t writeVlqI(int64_t i);
+  size_t writeVlqS(size_t i);
+
+  size_t readVlqU(uint64_t& i);
+  size_t readVlqI(int64_t& i);
+  size_t readVlqS(size_t& i);
+
+  uint64_t readVlqU();
+  int64_t readVlqI();
+  size_t readVlqS();
+
+  // The following functions write / read data with length and then content
+  // following, but note that the length is encoded as an unsigned VLQ integer.
+  // String objects are encoded in utf8, and can optionally be written as null
+  // terminated rather than length then content.
+
+  DataStream& operator<<(const char* s);
+  DataStream& operator<<(std::string const& d);
+  DataStream& operator<<(ByteArray const& d);
+  DataStream& operator<<(String const& s);
+
+  DataStream& operator>>(std::string& d);
+  DataStream& operator>>(ByteArray& d);
+  DataStream& operator>>(String& s);
+
+  // All enum types are automatically serializable
+
+  template <typename EnumType, typename = typename std::enable_if<std::is_enum<EnumType>::value>::type>
+  DataStream& operator<<(EnumType const& e);
+
+  template <typename EnumType, typename = typename std::enable_if<std::is_enum<EnumType>::value>::type>
+  DataStream& operator>>(EnumType& e);
+
+  // Convenience method to avoid temporary.
+  template <typename T>
+  T read();
+
+  // Convenient argument style reading / writing
+
+  template <typename Data>
+  void read(Data& data);
+
+  template <typename Data>
+  void write(Data const& data);
+
+  // Argument style reading / writing with casting.
+
+  template <typename ReadType, typename Data>
+  void cread(Data& data);
+
+  template <typename WriteType, typename Data>
+  void cwrite(Data const& data);
+
+  // Argument style reading / writing of variable length integers.  Arguments
+  // are explicitly casted, so things like enums are allowed.
+
+  template <typename IntegralType>
+  void vuread(IntegralType& data);
+
+  template <typename IntegralType>
+  void viread(IntegralType& data);
+
+  template <typename IntegralType>
+  void vsread(IntegralType& data);
+
+  template <typename IntegralType>
+  void vuwrite(IntegralType const& data);
+
+  template <typename IntegralType>
+  void viwrite(IntegralType const& data);
+
+  template <typename IntegralType>
+  void vswrite(IntegralType const& data);
+
+  // Store a fixed point number as a variable length integer
+
+  template <typename FloatType>
+  void vfread(FloatType& data, FloatType base);
+
+  template <typename FloatType>
+  void vfwrite(FloatType const& data, FloatType base);
+
+  // Read a shared / unique ptr, and store whether the pointer is initialized.
+
+  template <typename PointerType, typename ReadFunction>
+  void pread(PointerType& pointer, ReadFunction readFunction);
+
+  template <typename PointerType, typename WriteFunction>
+  void pwrite(PointerType const& pointer, WriteFunction writeFunction);
+
+  template <typename PointerType>
+  void pread(PointerType& pointer);
+
+  template <typename PointerType>
+  void pwrite(PointerType const& pointer);
+
+  // WriteFunction should be void (DataStream& ds, Element const& e)
+  template <typename Container, typename WriteFunction>
+  void writeContainer(Container const& container, WriteFunction function);
+
+  // ReadFunction should be void (DataStream& ds, Element& e)
+  template <typename Container, typename ReadFunction>
+  void readContainer(Container& container, ReadFunction function);
+
+  template <typename Container, typename WriteFunction>
+  void writeMapContainer(Container& map, WriteFunction function);
+
+  // Specialization of readContainer for map types (whose elements are a pair
+  // with the key type marked const)
+  template <typename Container, typename ReadFunction>
+  void readMapContainer(Container& map, ReadFunction function);
+
+  template <typename Container>
+  void writeContainer(Container const& container);
+
+  template <typename Container>
+  void readContainer(Container& container);
+
+  template <typename Container>
+  void writeMapContainer(Container const& container);
+
+  template <typename Container>
+  void readMapContainer(Container& container);
+
+private:
+  void writeStringData(char const* data, size_t len);
+
+  ByteOrder m_byteOrder;
+  bool m_nullTerminatedStrings;
+  unsigned m_streamCompatibilityVersion;
+};
+
+template <typename EnumType, typename>
+DataStream& DataStream::operator<<(EnumType const& e) {
+  *this << (typename std::underlying_type<EnumType>::type)e;
+  return *this;
+}
+
+template <typename EnumType, typename>
+DataStream& DataStream::operator>>(EnumType& e) {
+  typename std::underlying_type<EnumType>::type i;
+  *this >> i;
+  e = (EnumType)i;
+  return *this;
+}
+
+template <typename T>
+T DataStream::read() {
+  T t;
+  *this >> t;
+  return t;
+}
+
+template <typename Data>
+void DataStream::read(Data& data) {
+  *this >> data;
+}
+
+template <typename Data>
+void DataStream::write(Data const& data) {
+  *this << data;
+}
+
+template <typename ReadType, typename Data>
+void DataStream::cread(Data& data) {
+  ReadType v;
+  *this >> v;
+  data = (Data)v;
+}
+
+template <typename WriteType, typename Data>
+void DataStream::cwrite(Data const& data) {
+  WriteType v = (WriteType)data;
+  *this << v;
+}
+
+template <typename IntegralType>
+void DataStream::vuread(IntegralType& data) {
+  uint64_t i = readVlqU();
+  data = (IntegralType)i;
+}
+
+template <typename IntegralType>
+void DataStream::viread(IntegralType& data) {
+  int64_t i = readVlqI();
+  data = (IntegralType)i;
+}
+
+template <typename IntegralType>
+void DataStream::vsread(IntegralType& data) {
+  size_t s = readVlqS();
+  data = (IntegralType)s;
+}
+
+template <typename IntegralType>
+void DataStream::vuwrite(IntegralType const& data) {
+  writeVlqU((uint64_t)data);
+}
+
+template <typename IntegralType>
+void DataStream::viwrite(IntegralType const& data) {
+  writeVlqI((int64_t)data);
+}
+
+template <typename IntegralType>
+void DataStream::vswrite(IntegralType const& data) {
+  writeVlqS((size_t)data);
+}
+
+template <typename FloatType>
+void DataStream::vfread(FloatType& data, FloatType base) {
+  int64_t i = readVlqI();
+  data = (FloatType)i * base;
+}
+
+template <typename FloatType>
+void DataStream::vfwrite(FloatType const& data, FloatType base) {
+  writeVlqI((int64_t)round(data / base));
+}
+
+template <typename PointerType, typename ReadFunction>
+void DataStream::pread(PointerType& pointer, ReadFunction readFunction) {
+  bool initialized = read<bool>();
+  if (initialized) {
+    auto element = make_unique<typename std::decay<typename PointerType::element_type>::type>();
+    readFunction(*this, *element);
+    pointer.reset(element.release());
+  } else {
+    pointer.reset();
+  }
+}
+
+template <typename PointerType, typename WriteFunction>
+void DataStream::pwrite(PointerType const& pointer, WriteFunction writeFunction) {
+  if (pointer) {
+    write(true);
+    writeFunction(*this, *pointer);
+  } else {
+    write(false);
+  }
+}
+
+template <typename PointerType>
+void DataStream::pread(PointerType& pointer) {
+  return pread(pointer, [](DataStream& ds, typename std::decay<typename PointerType::element_type>::type& value) {
+      ds.read(value);
+    });
+}
+
+template <typename PointerType>
+void DataStream::pwrite(PointerType const& pointer) {
+  return pwrite(pointer, [](DataStream& ds, typename std::decay<typename PointerType::element_type>::type const& value) {
+      ds.write(value);
+    });
+}
+
+template <typename Container, typename WriteFunction>
+void DataStream::writeContainer(Container const& container, WriteFunction function) {
+  writeVlqU(container.size());
+  for (auto const& elem : container)
+    function(*this, elem);
+}
+
+template <typename Container, typename ReadFunction>
+void DataStream::readContainer(Container& container, ReadFunction function) {
+  container.clear();
+  size_t size = readVlqU();
+  for (size_t i = 0; i < size; ++i) {
+    typename Container::value_type elem;
+    function(*this, elem);
+    container.insert(container.end(), elem);
+  }
+}
+
+template <typename Container, typename WriteFunction>
+void DataStream::writeMapContainer(Container& map, WriteFunction function) {
+  writeVlqU(map.size());
+  for (auto const& elem : map)
+    function(*this, elem.first, elem.second);
+}
+
+template <typename Container, typename ReadFunction>
+void DataStream::readMapContainer(Container& map, ReadFunction function) {
+  map.clear();
+  size_t size = readVlqU();
+  for (size_t i = 0; i < size; ++i) {
+    typename Container::key_type key;
+    typename Container::mapped_type mapped;
+    function(*this, key, mapped);
+    map.insert(make_pair(move(key), move(mapped)));
+  }
+}
+
+template <typename Container>
+void DataStream::writeContainer(Container const& container) {
+  writeContainer(container, [](DataStream& ds, typename Container::value_type const& element) { ds << element; });
+}
+
+template <typename Container>
+void DataStream::readContainer(Container& container) {
+  readContainer(container, [](DataStream& ds, typename Container::value_type& element) { ds >> element; });
+}
+
+template <typename Container>
+void DataStream::writeMapContainer(Container const& container) {
+  writeMapContainer(container, [](DataStream& ds, typename Container::key_type const& key, typename Container::mapped_type const& mapped) {
+      ds << key;
+      ds << mapped;
+    });
+}
+
+template <typename Container>
+void DataStream::readMapContainer(Container& container) {
+  readMapContainer(container, [](DataStream& ds, typename Container::key_type& key, typename Container::mapped_type& mapped) {
+      ds >> key;
+      ds >> mapped;
+    });
+}
+
+}
+
+#endif