Chris@16: //
Chris@16: // detail/buffered_stream_storage.hpp
Chris@16: // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Chris@16: //
Chris@101: // Copyright (c) 2003-2015 Christopher M. Kohlhoff (chris at kohlhoff dot com)
Chris@16: //
Chris@16: // Distributed under the Boost Software License, Version 1.0. (See accompanying
Chris@16: // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
Chris@16: //
Chris@16: 
Chris@16: #ifndef BOOST_ASIO_DETAIL_BUFFERED_STREAM_STORAGE_HPP
Chris@16: #define BOOST_ASIO_DETAIL_BUFFERED_STREAM_STORAGE_HPP
Chris@16: 
Chris@16: #if defined(_MSC_VER) && (_MSC_VER >= 1200)
Chris@16: # pragma once
Chris@16: #endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
Chris@16: 
Chris@16: #include <boost/asio/detail/config.hpp>
Chris@16: #include <boost/asio/buffer.hpp>
Chris@16: #include <boost/asio/detail/assert.hpp>
Chris@16: #include <cstddef>
Chris@16: #include <cstring>
Chris@16: #include <vector>
Chris@16: 
Chris@16: #include <boost/asio/detail/push_options.hpp>
Chris@16: 
Chris@16: namespace boost {
Chris@16: namespace asio {
Chris@16: namespace detail {
Chris@16: 
Chris@16: class buffered_stream_storage
Chris@16: {
Chris@16: public:
Chris@16:   // The type of the bytes stored in the buffer.
Chris@16:   typedef unsigned char byte_type;
Chris@16: 
Chris@16:   // The type used for offsets into the buffer.
Chris@16:   typedef std::size_t size_type;
Chris@16: 
Chris@16:   // Constructor.
Chris@16:   explicit buffered_stream_storage(std::size_t buffer_capacity)
Chris@16:     : begin_offset_(0),
Chris@16:       end_offset_(0),
Chris@16:       buffer_(buffer_capacity)
Chris@16:   {
Chris@16:   }
Chris@16: 
Chris@16:   /// Clear the buffer.
Chris@16:   void clear()
Chris@16:   {
Chris@16:     begin_offset_ = 0;
Chris@16:     end_offset_ = 0;
Chris@16:   }
Chris@16: 
Chris@16:   // Return a pointer to the beginning of the unread data.
Chris@16:   mutable_buffer data()
Chris@16:   {
Chris@16:     return boost::asio::buffer(buffer_) + begin_offset_;
Chris@16:   }
Chris@16: 
Chris@16:   // Return a pointer to the beginning of the unread data.
Chris@16:   const_buffer data() const
Chris@16:   {
Chris@16:     return boost::asio::buffer(buffer_) + begin_offset_;
Chris@16:   }
Chris@16: 
Chris@16:   // Is there no unread data in the buffer.
Chris@16:   bool empty() const
Chris@16:   {
Chris@16:     return begin_offset_ == end_offset_;
Chris@16:   }
Chris@16: 
Chris@16:   // Return the amount of unread data the is in the buffer.
Chris@16:   size_type size() const
Chris@16:   {
Chris@16:     return end_offset_ - begin_offset_;
Chris@16:   }
Chris@16: 
Chris@16:   // Resize the buffer to the specified length.
Chris@16:   void resize(size_type length)
Chris@16:   {
Chris@16:     BOOST_ASIO_ASSERT(length <= capacity());
Chris@16:     if (begin_offset_ + length <= capacity())
Chris@16:     {
Chris@16:       end_offset_ = begin_offset_ + length;
Chris@16:     }
Chris@16:     else
Chris@16:     {
Chris@16:       using namespace std; // For memmove.
Chris@16:       memmove(&buffer_[0], &buffer_[0] + begin_offset_, size());
Chris@16:       end_offset_ = length;
Chris@16:       begin_offset_ = 0;
Chris@16:     }
Chris@16:   }
Chris@16: 
Chris@16:   // Return the maximum size for data in the buffer.
Chris@16:   size_type capacity() const
Chris@16:   {
Chris@16:     return buffer_.size();
Chris@16:   }
Chris@16: 
Chris@16:   // Consume multiple bytes from the beginning of the buffer.
Chris@16:   void consume(size_type count)
Chris@16:   {
Chris@16:     BOOST_ASIO_ASSERT(begin_offset_ + count <= end_offset_);
Chris@16:     begin_offset_ += count;
Chris@16:     if (empty())
Chris@16:       clear();
Chris@16:   }
Chris@16: 
Chris@16: private:
Chris@16:   // The offset to the beginning of the unread data.
Chris@16:   size_type begin_offset_;
Chris@16: 
Chris@16:   // The offset to the end of the unread data.
Chris@16:   size_type end_offset_;
Chris@16:   
Chris@16:   // The data in the buffer.
Chris@16:   std::vector<byte_type> buffer_;
Chris@16: };
Chris@16: 
Chris@16: } // namespace detail
Chris@16: } // namespace asio
Chris@16: } // namespace boost
Chris@16: 
Chris@16: #include <boost/asio/detail/pop_options.hpp>
Chris@16: 
Chris@16: #endif // BOOST_ASIO_DETAIL_BUFFERED_STREAM_STORAGE_HPP