byte_stream.h

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/******************************************************************************
The MIT License(MIT)
 
Embedded Template Library.
https://github.com/ETLCPP/etl
https://www.etlcpp.com
 
Copyright(c) 2021 John Wellbelove
 
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files(the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and / or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions :
 
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
 
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
******************************************************************************/
 
#ifndef ETL_BYTE_STREAM_INCLUDED
#define ETL_BYTE_STREAM_INCLUDED
 
#include "platform.h"
#include "algorithm.h"
#include "delegate.h"
#include "endianness.h"
#include "error_handler.h"
#include "exception.h"
#include "integral_limits.h"
#include "iterator.h"
#include "memory.h"
#include "optional.h"
#include "span.h"
#include "type_traits.h"
 
#include <stddef.h>
 
namespace etl
{
  //***************************************************************************
  //***************************************************************************
  class byte_stream_writer
  {
  public:
 
    typedef char*                                        iterator;
    typedef const char*                                  const_iterator;
    typedef etl::span<char>                              callback_parameter_type;
    typedef etl::delegate<void(callback_parameter_type)> callback_type;
 
    //***************************************************************************
    //***************************************************************************
    byte_stream_writer(etl::span<char> span_, etl::endian stream_endianness_, callback_type callback_ = callback_type())
      : pdata(span_.begin())
      , pcurrent(span_.begin())
      , stream_length(span_.size_bytes())
      , stream_endianness(stream_endianness_)
      , callback(callback_)
    {
    }
 
    //***************************************************************************
    //***************************************************************************
    byte_stream_writer(etl::span<unsigned char> span_, etl::endian stream_endianness_, callback_type callback_ = callback_type())
      : pdata(reinterpret_cast<char*>(span_.begin()))
      , pcurrent(reinterpret_cast<char*>(span_.begin()))
      , stream_length(span_.size_bytes())
      , stream_endianness(stream_endianness_)
      , callback(callback_)
    {
    }
 
    //***************************************************************************
    //***************************************************************************
    byte_stream_writer(void* begin_, void* end_, etl::endian stream_endianness_, callback_type callback_ = callback_type())
      : pdata(reinterpret_cast<char*>(begin_))
      , pcurrent(reinterpret_cast<char*>(begin_))
      , stream_length(static_cast<size_t>(etl::distance(reinterpret_cast<char*>(begin_), reinterpret_cast<char*>(end_))))
      , stream_endianness(stream_endianness_)
      , callback(callback_)
    {
    }
 
    //***************************************************************************
    //***************************************************************************
    byte_stream_writer(void* begin_, size_t length_, etl::endian stream_endianness_, callback_type callback_ = callback_type())
      : pdata(reinterpret_cast<char*>(begin_))
      , pcurrent(reinterpret_cast<char*>(begin_))
      , stream_length(length_)
      , stream_endianness(stream_endianness_)
      , callback(callback_)
    {
    }
 
    //***************************************************************************
    //***************************************************************************
    template <typename T, size_t Size>
    byte_stream_writer(T (&begin_)[Size], etl::endian stream_endianness_, callback_type callback_ = callback_type())
      : pdata(begin_)
      , pcurrent(begin_)
      , stream_length(begin_ + (Size * sizeof(T)))
      , stream_endianness(stream_endianness_)
      , callback(callback_)
    {
    }
 
    //***************************************************************************
    //***************************************************************************
    void write_unchecked(bool value)
    {
      *pcurrent++ = value ? 1 : 0;
    }
 
    //***************************************************************************
    //***************************************************************************
    bool write(bool value)
    {
      bool success = (available<bool>() > 0U);
 
      if (success)
      {
        write_unchecked(value);
      }
 
      return success;
    }
 
    //***************************************************************************
    //***************************************************************************
    template <typename T>
    typename etl::enable_if<etl::is_integral<T>::value || etl::is_floating_point<T>::value, void>::type write_unchecked(T value)
    {
      to_bytes<T>(value);
    }
 
    //***************************************************************************
    //***************************************************************************
    template <typename T>
    typename etl::enable_if<etl::is_integral<T>::value || etl::is_floating_point<T>::value, bool>::type write(T value)
    {
      bool success = (available<T>() > 0U);
 
      if (success)
      {
        write_unchecked(value);
      }
 
      return success;
    }
 
    //***************************************************************************
    //***************************************************************************
    template <typename T>
    typename etl::enable_if<etl::is_integral<T>::value || etl::is_floating_point<T>::value, void>::type write_unchecked(const etl::span<T>& range)
    {
      typename etl::span<T>::iterator itr = range.begin();
 
      while (itr != range.end())
      {
        to_bytes(*itr);
        ++itr;
      }
    }
 
    //***************************************************************************
    //***************************************************************************
    template <typename T>
    typename etl::enable_if<etl::is_integral<T>::value || etl::is_floating_point<T>::value, bool>::type write(const etl::span<T>& range)
    {
      bool success = (available<T>() >= range.size());
 
      if (success)
      {
        write_unchecked(range);
      }
 
      return success;
    }
 
    //***************************************************************************
    //***************************************************************************
    template <typename T>
    typename etl::enable_if<etl::is_integral<T>::value || etl::is_floating_point<T>::value, void>::type write_unchecked(const T* start, size_t length)
    {
      while (length-- != 0U)
      {
        to_bytes(*start);
        ++start;
      }
    }
 
    //***************************************************************************
    //***************************************************************************
    template <typename T>
    typename etl::enable_if<etl::is_integral<T>::value || etl::is_floating_point<T>::value, bool>::type write(const T* start, size_t length)
    {
      bool success = (available<T>() >= length);
 
      if (success)
      {
        write_unchecked(start, length);
      }
 
      return success;
    }
 
    //***************************************************************************
    //***************************************************************************
    template <typename T>
    bool skip(size_t n)
    {
      bool success = (available<T>() >= n);
 
      if (success)
      {
        step(n * sizeof(T));
      }
 
      return success;
    }
 
    //***************************************************************************
    //***************************************************************************
    void restart(size_t n = 0U)
    {
      pcurrent = pdata + n;
    }
 
    //***************************************************************************
    //***************************************************************************
    iterator begin()
    {
      return pdata;
    }
 
    //***************************************************************************
    //***************************************************************************
    const_iterator begin() const
    {
      return pdata;
    }
 
    //***************************************************************************
    //***************************************************************************
    iterator end()
    {
      return pcurrent;
    }
 
    //***************************************************************************
    //***************************************************************************
    const_iterator end() const
    {
      return pcurrent;
    }
 
    //***************************************************************************
    //***************************************************************************
    const_iterator cbegin() const
    {
      return pdata;
    }
 
    //***************************************************************************
    //***************************************************************************
    const_iterator cend() const
    {
      return pcurrent;
    }
 
    //***************************************************************************
    //***************************************************************************
    etl::span<char> used_data()
    {
      return etl::span<char>(pdata, pcurrent);
    }
 
    //***************************************************************************
    //***************************************************************************
    etl::span<const char> used_data() const
    {
      return etl::span<const char>(pdata, pcurrent);
    }
 
    //***************************************************************************
    //***************************************************************************
    etl::span<char> free_data()
    {
      return etl::span<char>(pcurrent, pdata + stream_length);
    }
 
    //***************************************************************************
    //***************************************************************************
    etl::span<const char> free_data() const
    {
      return etl::span<const char>(pcurrent, pdata + stream_length);
    }
 
    //***************************************************************************
    //***************************************************************************
    etl::span<char> data()
    {
      return etl::span<char>(pdata, pdata + stream_length);
    }
 
    //***************************************************************************
    //***************************************************************************
    etl::span<const char> data() const
    {
      return etl::span<const char>(pdata, pdata + stream_length);
    }
 
    //***************************************************************************
    //***************************************************************************
    bool full() const
    {
      return size_bytes() == capacity();
    }
 
    //***************************************************************************
    //***************************************************************************
    bool empty() const
    {
      return size_bytes() == 0U;
    }
 
    //***************************************************************************
    //***************************************************************************
    size_t size_bytes() const
    {
      return static_cast<size_t>(etl::distance(pdata, pcurrent));
    }
 
    //***************************************************************************
    //***************************************************************************
    size_t capacity() const
    {
      return stream_length;
    }
 
    //***************************************************************************
    //***************************************************************************
    template <typename T>
    size_t available() const
    {
      return (capacity() - size_bytes()) / sizeof(T);
    }
 
    //***************************************************************************
    //***************************************************************************
    size_t available_bytes() const
    {
      return available<char>();
    }
 
    //***************************************************************************
    //***************************************************************************
    void set_callback(callback_type callback_)
    {
      callback = callback_;
    }
 
    //***************************************************************************
    //***************************************************************************
    callback_type get_callback() const
    {
      return callback;
    }
 
    //***************************************************************************
    //***************************************************************************
    etl::endian get_endianness() const
    {
      return stream_endianness;
    }
 
  private:
 
    //***************************************************************************
    //***************************************************************************
    template <typename T>
    typename etl::enable_if<sizeof(T) == 1U, void>::type to_bytes(const T value)
    {
      *pcurrent = static_cast<char>(value);
      step(1U);
    }
 
    //*********************************
    template <typename T>
    typename etl::enable_if<sizeof(T) != 1U, void>::type to_bytes(const T value)
    {
      const char* pv = reinterpret_cast<const char*>(&value);
      copy_value(pv, pcurrent, sizeof(T));
      step(sizeof(T));
    }
 
    //*********************************
    void step(size_t n)
    {
      callback.call_if(etl::span<char>(pcurrent, pcurrent + n));
 
      pcurrent += n;
    }
 
    //*********************************
    void copy_value(const char* source, char* destination, size_t length) const
    {
      const etl::endian platform_endianness = etl::endianness::value();
 
      if (stream_endianness == platform_endianness)
      {
        etl::copy(source, source + length, destination);
      }
      else
      {
        etl::reverse_copy(source, source + length, destination);
      }
    }
 
    char* const       pdata;             
    char*             pcurrent;          
    const size_t      stream_length;     
    const etl::endian stream_endianness; 
    callback_type     callback;          
  };
 
  //***************************************************************************
  //***************************************************************************
  class byte_stream_reader
  {
  public:
 
    typedef char*       iterator;
    typedef const char* const_iterator;
 
    //***************************************************************************
    //***************************************************************************
    byte_stream_reader(etl::span<char> span_, etl::endian stream_endianness_)
      : pdata(span_.begin())
      , pcurrent(span_.begin())
      , stream_length(span_.size_bytes())
      , stream_endianness(stream_endianness_)
    {
    }
 
    //***************************************************************************
    //***************************************************************************
    byte_stream_reader(etl::span<const char> span_, etl::endian stream_endianness_)
      : pdata(span_.begin())
      , pcurrent(span_.begin())
      , stream_length(span_.size_bytes())
      , stream_endianness(stream_endianness_)
    {
    }
 
    //***************************************************************************
    //***************************************************************************
    byte_stream_reader(const void* begin_, const void* end_, etl::endian stream_endianness_)
      : pdata(reinterpret_cast<const char*>(begin_))
      , pcurrent(reinterpret_cast<const char*>(begin_))
      , stream_length(static_cast<size_t>(etl::distance(reinterpret_cast<const char*>(begin_), reinterpret_cast<const char*>(end_))))
      , stream_endianness(stream_endianness_)
    {
    }
 
    //***************************************************************************
    //***************************************************************************
    byte_stream_reader(const void* begin_, size_t length_, etl::endian stream_endianness_)
      : pdata(reinterpret_cast<const char*>(begin_))
      , pcurrent(reinterpret_cast<const char*>(begin_))
      , stream_length(length_)
      , stream_endianness(stream_endianness_)
    {
    }
 
    //***************************************************************************
    //***************************************************************************
    template <typename T, size_t Size>
    byte_stream_reader(T (&begin_)[Size], etl::endian stream_endianness_)
      : pdata(begin_)
      , pcurrent(begin_)
      , stream_length(begin_ + (Size * sizeof(T)))
      , stream_endianness(stream_endianness_)
    {
    }
 
    //***************************************************************************
    //***************************************************************************
    template <typename T, size_t Size>
    byte_stream_reader(const T (&begin_)[Size], etl::endian stream_endianness_)
      : pdata(begin_)
      , pcurrent(begin_)
      , stream_length(begin_ + (Size * sizeof(T)))
      , stream_endianness(stream_endianness_)
    {
    }
 
    //***************************************************************************
    //***************************************************************************
    template <typename T>
    typename etl::enable_if< etl::is_integral<T>::value || etl::is_floating_point<T>::value, T>::type read_unchecked()
    {
      return from_bytes<T>();
    }
 
    //***************************************************************************
    //***************************************************************************
    template <typename T>
    typename etl::enable_if<etl::is_integral<T>::value || etl::is_floating_point<T>::value, etl::optional<T> >::type read()
    {
      etl::optional<T> result;
 
      // Do we have enough room?
      if (available<T>() > 0U)
      {
        result = read_unchecked<T>();
      }
 
      return result;
    }
 
    //***************************************************************************
    //***************************************************************************
    template <typename T>
    typename etl::enable_if<sizeof(T) == 1U, etl::span<const T> >::type read_unchecked(size_t n)
    {
      etl::span<const T> result;
 
      const char* pend = pcurrent + (n * sizeof(T));
 
      result   = etl::span<const T>(reinterpret_cast<const T*>(pcurrent), reinterpret_cast<const T*>(pend));
      pcurrent = pend;
 
      return result;
    }
 
    //***************************************************************************
    //***************************************************************************
    template <typename T>
    typename etl::enable_if<sizeof(T) == 1U, etl::optional<etl::span<const T> > >::type read(size_t n)
    {
      etl::optional<etl::span<const T> > result;
 
      // Do we have enough room?
      if (available<T>() >= n)
      {
        result = read_unchecked<T>(n);
      }
 
      return result;
    }
 
    //***************************************************************************
    //***************************************************************************
    template <typename T>
    typename etl::enable_if<etl::is_integral<T>::value || etl::is_floating_point<T>::value, etl::span<const T> >::type
      read_unchecked(etl::span<T> range)
    {
      typename etl::span<T>::iterator destination = range.begin();
 
      while (destination != range.end())
      {
        *destination++ = from_bytes<T>();
      }
 
      return etl::span<const T>(range.begin(), range.end());
    }
 
    //***************************************************************************
    //***************************************************************************
    template <typename T>
    typename etl::enable_if<etl::is_integral<T>::value || etl::is_floating_point<T>::value, etl::optional<etl::span<const T> > >::type
      read(etl::span<T> range)
    {
      // Do we have enough room?
      if (available<T>() >= range.size())
      {
        return etl::optional<etl::span<const T> >(read_unchecked<T>(range));
      }
 
      return etl::optional<etl::span<const T> >();
    }
 
    //***************************************************************************
    //***************************************************************************
    template <typename T>
    typename etl::enable_if<etl::is_integral<T>::value || etl::is_floating_point<T>::value, etl::span<const T> >::type read_unchecked(T*     start,
                                                                                                                                      size_t length)
    {
      T* destination = start;
 
      for (size_t i = 0; i < length; ++i)
      {
        *destination++ = from_bytes<T>();
      }
 
      return etl::span<const T>(start, length);
    }
 
    //***************************************************************************
    //***************************************************************************
    template <typename T>
    typename etl::enable_if<etl::is_integral<T>::value || etl::is_floating_point<T>::value, etl::optional<etl::span<const T> > >::type
      read(T* start, size_t length)
    {
      // Do we have enough room?
      if (available<T>() >= length)
      {
        return etl::optional<etl::span<const T> >(read_unchecked<T>(start, length));
      }
 
      return etl::optional<etl::span<const T> >();
    }
 
    //***************************************************************************
    //***************************************************************************
    template <typename T>
    bool skip(size_t n)
    {
      if (n <= available<T>())
      {
        pcurrent += (n * sizeof(T));
        return true;
      }
      else
      {
        return false;
      }
    }
 
    //***************************************************************************
    //***************************************************************************
    void restart(size_t n = 0U)
    {
      pcurrent = pdata + n;
    }
 
    //***************************************************************************
    //***************************************************************************
    const_iterator begin() const
    {
      return pdata;
    }
 
    //***************************************************************************
    //***************************************************************************
    const_iterator end() const
    {
      return pcurrent;
    }
 
    //***************************************************************************
    //***************************************************************************
    const_iterator cbegin() const
    {
      return pdata;
    }
 
    //***************************************************************************
    //***************************************************************************
    const_iterator cend() const
    {
      return pcurrent;
    }
 
    //***************************************************************************
    //***************************************************************************
    etl::span<const char> used_data() const
    {
      return etl::span<const char>(pdata, pcurrent);
    }
 
    //***************************************************************************
    //***************************************************************************
    etl::span<const char> free_data() const
    {
      return etl::span<const char>(pcurrent, pdata + stream_length);
    }
 
    //***************************************************************************
    //***************************************************************************
    etl::span<const char> data() const
    {
      return etl::span<const char>(pdata, pdata + stream_length);
    }
 
    //***************************************************************************
    //***************************************************************************
    bool empty() const
    {
      return available<char>() == 0U;
    }
 
    //***************************************************************************
    //***************************************************************************
    size_t size_bytes() const
    {
      return stream_length;
    }
 
    //***************************************************************************
    //***************************************************************************
    template <typename T>
    size_t available() const
    {
      size_t used = static_cast<size_t>(etl::distance(pdata, pcurrent));
 
      return (stream_length - used) / sizeof(T);
    }
 
    //***************************************************************************
    //***************************************************************************
    size_t available_bytes() const
    {
      return available<char>();
    }
 
    //***************************************************************************
    //***************************************************************************
    etl::endian get_endianness() const
    {
      return stream_endianness;
    }
 
  private:
 
    //***************************************************************************
    //***************************************************************************
    template <typename T>
    typename etl::enable_if<sizeof(T) == 1U, T>::type from_bytes()
    {
      return static_cast<T>(*pcurrent++);
    }
 
    //*********************************
    template <typename T>
    typename etl::enable_if<sizeof(T) != 1U, T>::type from_bytes()
    {
      T value;
 
      char* pv = reinterpret_cast<char*>(&value);
      copy_value(pcurrent, pv, sizeof(T));
      pcurrent += sizeof(T);
 
      return value;
    }
 
    //*********************************
    void copy_value(const char* source, char* destination, size_t length) const
    {
      const etl::endian platform_endianness = etl::endianness::value();
 
      if (stream_endianness == platform_endianness)
      {
        etl::copy(source, source + length, destination);
      }
      else
      {
        etl::reverse_copy(source, source + length, destination);
      }
    }
 
    const char* const pdata;             
    const char*       pcurrent;          
    const size_t      stream_length;     
    const etl::endian stream_endianness; 
  };
 
  //***************************************************************************
  //***************************************************************************
  template <typename T>
  void write_unchecked(etl::byte_stream_writer& stream, const T& value)
  {
    stream.write_unchecked(value);
  }
 
  //***************************************************************************
  //***************************************************************************
  template <typename T>
  bool write(etl::byte_stream_writer& stream, const T& value)
  {
    return stream.write(value);
  }
 
  //***************************************************************************
  //***************************************************************************
  template <typename T>
  T read_unchecked(etl::byte_stream_reader& stream)
  {
    return stream.read_unchecked<T>();
  }
 
  //***************************************************************************
  //***************************************************************************
  template <typename T>
  etl::optional<T> read(etl::byte_stream_reader& stream)
  {
    return stream.read<T>();
  }
} // namespace etl
 
#endif