boost/interprocess/streams/vectorstream.hpp
////////////////////////////////////////////////////////////////////////////// // // (C) Copyright Ion Gaztanaga 2005-2008. Distributed under the Boost // Software License, Version 1.0. (See accompanying file // LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) // // See http://www.boost.org/libs/interprocess for documentation. // ////////////////////////////////////////////////////////////////////////////// // // This file comes from SGI's sstream file. Modified by Ion Gaztanaga 2005. // Changed internal SGI string to a generic, templatized vector. Added efficient // internal buffer get/set/swap functions, so that we can obtain/establish the // internal buffer without any reallocation or copy. Kill those temporaries! /////////////////////////////////////////////////////////////////////////////// /* * Copyright (c) 1998 * Silicon Graphics Computer Systems, Inc. * * Permission to use, copy, modify, distribute and sell this software * and its documentation for any purpose is hereby granted without fee, * provided that the above copyright notice appear in all copies and * that both that copyright notice and this permission notice appear * in supporting documentation. Silicon Graphics makes no * representations about the suitability of this software for any * purpose. It is provided "as is" without express or implied warranty. */ //!\file //!This file defines basic_vectorbuf, basic_ivectorstream, //!basic_ovectorstream, and basic_vectorstreamclasses. These classes //!represent streamsbufs and streams whose sources or destinations are //!STL-like vectors that can be swapped with external vectors to avoid //!unnecessary allocations/copies. #ifndef BOOST_INTERPROCESS_VECTORSTREAM_HPP #define BOOST_INTERPROCESS_VECTORSTREAM_HPP #include <boost/interprocess/detail/config_begin.hpp> #include <boost/interprocess/detail/workaround.hpp> #include <iosfwd> #include <ios> #include <istream> #include <ostream> #include <string> // char traits #include <cstddef> // ptrdiff_t #include <boost/interprocess/interprocess_fwd.hpp> #include <cassert> namespace boost { namespace interprocess { //!A streambuf class that controls the transmission of elements to and from //!a basic_ivectorstream, basic_ovectorstream or basic_vectorstream. //!It holds a character vector specified by CharVector template parameter //!as its formatting buffer. The vector must have contiguous storage, like //!std::vector, boost::interprocess::vector or boost::interprocess::basic_string template <class CharVector, class CharTraits> class basic_vectorbuf : public std::basic_streambuf<typename CharVector::value_type, CharTraits> { public: typedef CharVector vector_type; typedef typename CharVector::value_type char_type; typedef typename CharTraits::int_type int_type; typedef typename CharTraits::pos_type pos_type; typedef typename CharTraits::off_type off_type; typedef CharTraits traits_type; /// @cond private: typedef std::basic_streambuf<char_type, traits_type> base_t; basic_vectorbuf(const basic_vectorbuf&); basic_vectorbuf & operator =(const basic_vectorbuf&); /// @endcond public: //!Constructor. Throws if vector_type default //!constructor throws. explicit basic_vectorbuf(std::ios_base::openmode mode = std::ios_base::in | std::ios_base::out) : base_t(), m_mode(mode) { this->initialize_pointers(); } //!Constructor. Throws if //!vector_type(const VectorParameter ¶m) throws. template<class VectorParameter> explicit basic_vectorbuf(const VectorParameter ¶m, std::ios_base::openmode mode = std::ios_base::in | std::ios_base::out) : base_t(), m_mode(mode), m_vect(param) { this->initialize_pointers(); } virtual ~basic_vectorbuf(){} public: //!Swaps the underlying vector with the passed vector. //!This function resets the read/write position in the stream. //!Does not throw. void swap_vector(vector_type &vect) { if (this->m_mode & std::ios_base::out){ //Update high water if necessary //And resize vector to remove extra size if (mp_high_water < base_t::pptr()){ //Restore the vector's size if necessary mp_high_water = base_t::pptr(); } m_vect.resize(mp_high_water - (m_vect.size() ? &m_vect[0] : 0)); //Now swap vector m_vect.swap(vect); //If the stream is writable put the high water mark //and maximize the size. typename vector_type::size_type old_size = m_vect.size(); m_vect.resize(m_vect.capacity()); this->initialize_pointers(); mp_high_water = old_size ? &m_vect[0] + old_size : 0; } else{ //Now swap vector m_vect.swap(vect); this->initialize_pointers(); } } //!Returns a const reference to the internal vector. //!Does not throw. const vector_type &vector() const { if (this->m_mode & std::ios_base::out){ if (mp_high_water < base_t::pptr()){ //Restore the vector's size if necessary mp_high_water = base_t::pptr(); } m_vect.resize(mp_high_water - (m_vect.size() ? &m_vect[0] : 0)); const_cast<basic_vectorbuf * const>(this)->initialize_pointers(); } return m_vect; } //!Preallocates memory from the internal vector. //!Resets the stream to the first position. //!Throws if the internals vector's memory allocation throws. void reserve(typename vector_type::size_type size) { m_vect.reserve(size); //Now update pointer data typename vector_type::size_type old_size = m_vect.size(); m_vect.resize(m_vect.capacity()); this->initialize_pointers(); mp_high_water = old_size ? &m_vect[0] + old_size : 0; } //!Calls clear() method of the internal vector. //!Resets the stream to the first position. void clear() { m_vect.clear(); this->initialize_pointers(); } /// @cond private: void initialize_pointers() { // The initial read position is the beginning of the vector. if(m_mode & std::ios_base::in){ if(m_vect.empty()){ this->setg(0, 0, 0); } else{ this->setg(&m_vect[0], &m_vect[0], &m_vect[0] + m_vect.size()); } } // The initial write position is the beginning of the vector. if(m_mode & std::ios_base::out){ if(m_vect.empty()){ this->setp(0, 0); } else{ this->setp(&m_vect[0], &m_vect[0] + m_vect.size()); } if (m_mode & (std::ios_base::app | std::ios_base::ate)) base_t::pbump((int)m_vect.size()); } mp_high_water = m_vect.empty() ? 0 : (&m_vect[0] + m_vect.size()); } protected: virtual int_type underflow() { if (base_t::gptr() == 0) return CharTraits::eof(); if (mp_high_water < base_t::pptr()) mp_high_water = base_t::pptr(); if (base_t::egptr() < mp_high_water) base_t::setg(base_t::eback(), base_t::gptr(), mp_high_water); if (base_t::gptr() < base_t::egptr()) return CharTraits::to_int_type(*base_t::gptr()); return CharTraits::eof(); } virtual int_type pbackfail(int_type c = CharTraits::eof()) { if(this->gptr() != this->eback()) { if(!CharTraits::eq_int_type(c, CharTraits::eof())) { if(CharTraits::eq(CharTraits::to_char_type(c), this->gptr()[-1])) { this->gbump(-1); return c; } else if(m_mode & std::ios_base::out) { this->gbump(-1); *this->gptr() = c; return c; } else return CharTraits::eof(); } else { this->gbump(-1); return CharTraits::not_eof(c); } } else return CharTraits::eof(); } virtual int_type overflow(int_type c = CharTraits::eof()) { if(m_mode & std::ios_base::out) { if(!CharTraits::eq_int_type(c, CharTraits::eof())) { // if(!(m_mode & std::ios_base::in)) { // if(this->pptr() < this->epptr()) { // *this->pptr() = CharTraits::to_char_type(c); // this->pbump(1); // if (mp_high_water < base_t::pptr()) // mp_high_water = base_t::pptr(); // if ((m_mode & std::ios_base::in) && base_t::egptr() < mp_high_water) // base_t::setg(base_t::eback(), base_t::gptr(), mp_high_water); // return c; // } // else // return CharTraits::eof(); // } // else { // try{ typedef typename vector_type::difference_type dif_t; dif_t inpos = base_t::gptr() - base_t::eback(); //The new output position is the previous one plus one //because 'overflow' requires putting 'c' on the buffer dif_t new_outpos = base_t::pptr() - base_t::pbase() + 1; //Adjust high water if necessary dif_t hipos = mp_high_water - base_t::pbase(); if (hipos < new_outpos) hipos = new_outpos; //Insert the new data m_vect.push_back(CharTraits::to_char_type(c)); m_vect.resize(m_vect.capacity()); char_type* p = const_cast<char_type*>(&m_vect[0]); //A reallocation has happened, update pointers if (m_mode & std::ios_base::in) base_t::setg(p, p + inpos, p + hipos); base_t::setp(p, p + (dif_t)m_vect.size()); //Update write position to the old position + 1 base_t::pbump((int)new_outpos); //Update high water pointer, since the buffer has been reallocated mp_high_water = base_t::pbase() + hipos; return c; // } // catch(...){ // return CharTraits::eof(); // } // } } else // c is EOF, so we don't have to do anything return CharTraits::not_eof(c); } else // Overflow always fails if it's read-only. return CharTraits::eof(); } virtual pos_type seekoff(off_type off, std::ios_base::seekdir dir, std::ios_base::openmode mode = std::ios_base::in | std::ios_base::out) { bool in = false, out = false; const std::ios_base::openmode inout = std::ios_base::in | std::ios_base::out; if((mode & inout) == inout) { if(dir == std::ios_base::beg || dir == std::ios_base::end) in = out = true; } else if(mode & std::ios_base::in) in = true; else if(mode & std::ios_base::out) out = true; if(!in && !out) return pos_type(off_type(-1)); else if((in && (!(m_mode & std::ios_base::in) || this->gptr() == 0)) || (out && (!(m_mode & std::ios_base::out) || this->pptr() == 0))) return pos_type(off_type(-1)); off_type newoff; //Just calculate the end of the stream. If the stream is read-only //the limit is the size of the vector. Otherwise, the high water mark //will mark the real size. off_type limit = static_cast<off_type> (mode & std::ios_base::out ? mp_high_water - base_t::pbase() : m_vect.size()/*mp_high_water - base_t::eback()*/); switch(dir) { case std::ios_base::beg: newoff = 0; break; case std::ios_base::end: newoff = limit; break; case std::ios_base::cur: newoff = in ? static_cast<std::streamoff>(this->gptr() - this->eback()) : static_cast<std::streamoff>(this->pptr() - this->pbase()); break; default: return pos_type(off_type(-1)); } newoff += off; if (newoff < 0 || newoff > limit) return pos_type(-1); if (m_mode & std::ios_base::app && mode & std::ios_base::out && newoff != limit) return pos_type(-1); if (in) base_t::setg(base_t::eback(), base_t::eback() + newoff, base_t::egptr()); if (out){ base_t::setp(base_t::pbase(), base_t::epptr()); base_t::pbump(newoff); } return pos_type(newoff); } virtual pos_type seekpos(pos_type pos, std::ios_base::openmode mode = std::ios_base::in | std::ios_base::out) { return seekoff(pos - pos_type(off_type(0)), std::ios_base::beg, mode); } private: std::ios_base::openmode m_mode; mutable vector_type m_vect; mutable char_type* mp_high_water; /// @endcond }; //!A basic_istream class that holds a character vector specified by CharVector //!template parameter as its formatting buffer. The vector must have //!contiguous storage, like std::vector, boost::interprocess::vector or //!boost::interprocess::basic_string template <class CharVector, class CharTraits> class basic_ivectorstream : public std::basic_istream<typename CharVector::value_type, CharTraits> { public: typedef CharVector vector_type; typedef typename std::basic_ios <typename CharVector::value_type, CharTraits>::char_type char_type; typedef typename std::basic_ios<char_type, CharTraits>::int_type int_type; typedef typename std::basic_ios<char_type, CharTraits>::pos_type pos_type; typedef typename std::basic_ios<char_type, CharTraits>::off_type off_type; typedef typename std::basic_ios<char_type, CharTraits>::traits_type traits_type; /// @cond private: typedef std::basic_ios<char_type, CharTraits> basic_ios_t; typedef std::basic_istream<char_type, CharTraits> base_t; /// @endcond public: //!Constructor. Throws if vector_type default //!constructor throws. basic_ivectorstream(std::ios_base::openmode mode = std::ios_base::in) : basic_ios_t(), base_t(0), m_buf(mode | std::ios_base::in) { basic_ios_t::init(&m_buf); } //!Constructor. Throws if vector_type(const VectorParameter ¶m) //!throws. template<class VectorParameter> basic_ivectorstream(const VectorParameter ¶m, std::ios_base::openmode mode = std::ios_base::in) : basic_ios_t(), base_t(0), m_buf(param, mode | std::ios_base::in) { basic_ios_t::init(&m_buf); } ~basic_ivectorstream(){}; public: //!Returns the address of the stored //!stream buffer. basic_vectorbuf<CharVector, CharTraits>* rdbuf() const { return const_cast<basic_vectorbuf<CharVector, CharTraits>*>(&m_buf); } //!Swaps the underlying vector with the passed vector. //!This function resets the read position in the stream. //!Does not throw. void swap_vector(vector_type &vect) { m_buf.swap_vector(vect); } //!Returns a const reference to the internal vector. //!Does not throw. const vector_type &vector() const { return m_buf.vector(); } //!Calls reserve() method of the internal vector. //!Resets the stream to the first position. //!Throws if the internals vector's reserve throws. void reserve(typename vector_type::size_type size) { m_buf.reserve(size); } //!Calls clear() method of the internal vector. //!Resets the stream to the first position. void clear() { m_buf.clear(); } /// @cond private: basic_vectorbuf<CharVector, CharTraits> m_buf; /// @endcond }; //!A basic_ostream class that holds a character vector specified by CharVector //!template parameter as its formatting buffer. The vector must have //!contiguous storage, like std::vector, boost::interprocess::vector or //!boost::interprocess::basic_string template <class CharVector, class CharTraits> class basic_ovectorstream : public std::basic_ostream<typename CharVector::value_type, CharTraits> { public: typedef CharVector vector_type; typedef typename std::basic_ios <typename CharVector::value_type, CharTraits>::char_type char_type; typedef typename std::basic_ios<char_type, CharTraits>::int_type int_type; typedef typename std::basic_ios<char_type, CharTraits>::pos_type pos_type; typedef typename std::basic_ios<char_type, CharTraits>::off_type off_type; typedef typename std::basic_ios<char_type, CharTraits>::traits_type traits_type; /// @cond private: typedef std::basic_ios<char_type, CharTraits> basic_ios_t; typedef std::basic_ostream<char_type, CharTraits> base_t; /// @endcond public: //!Constructor. Throws if vector_type default //!constructor throws. basic_ovectorstream(std::ios_base::openmode mode = std::ios_base::out) : basic_ios_t(), base_t(0), m_buf(mode | std::ios_base::out) { basic_ios_t::init(&m_buf); } //!Constructor. Throws if vector_type(const VectorParameter ¶m) //!throws. template<class VectorParameter> basic_ovectorstream(const VectorParameter ¶m, std::ios_base::openmode mode = std::ios_base::out) : basic_ios_t(), base_t(0), m_buf(param, mode | std::ios_base::out) { basic_ios_t::init(&m_buf); } ~basic_ovectorstream(){} public: //!Returns the address of the stored //!stream buffer. basic_vectorbuf<CharVector, CharTraits>* rdbuf() const { return const_cast<basic_vectorbuf<CharVector, CharTraits>*>(&m_buf); } //!Swaps the underlying vector with the passed vector. //!This function resets the write position in the stream. //!Does not throw. void swap_vector(vector_type &vect) { m_buf.swap_vector(vect); } //!Returns a const reference to the internal vector. //!Does not throw. const vector_type &vector() const { return m_buf.vector(); } //!Calls reserve() method of the internal vector. //!Resets the stream to the first position. //!Throws if the internals vector's reserve throws. void reserve(typename vector_type::size_type size) { m_buf.reserve(size); } /// @cond private: basic_vectorbuf<CharVector, CharTraits> m_buf; /// @endcond }; //!A basic_iostream class that holds a character vector specified by CharVector //!template parameter as its formatting buffer. The vector must have //!contiguous storage, like std::vector, boost::interprocess::vector or //!boost::interprocess::basic_string template <class CharVector, class CharTraits> class basic_vectorstream : public std::basic_iostream<typename CharVector::value_type, CharTraits> { public: typedef CharVector vector_type; typedef typename std::basic_ios <typename CharVector::value_type, CharTraits>::char_type char_type; typedef typename std::basic_ios<char_type, CharTraits>::int_type int_type; typedef typename std::basic_ios<char_type, CharTraits>::pos_type pos_type; typedef typename std::basic_ios<char_type, CharTraits>::off_type off_type; typedef typename std::basic_ios<char_type, CharTraits>::traits_type traits_type; /// @cond private: typedef std::basic_ios<char_type, CharTraits> basic_ios_t; typedef std::basic_iostream<char_type, CharTraits> base_t; /// @endcond public: //!Constructor. Throws if vector_type default //!constructor throws. basic_vectorstream(std::ios_base::openmode mode = std::ios_base::in | std::ios_base::out) : basic_ios_t(), base_t(0), m_buf(mode) { basic_ios_t::init(&m_buf); } //!Constructor. Throws if vector_type(const VectorParameter ¶m) //!throws. template<class VectorParameter> basic_vectorstream(const VectorParameter ¶m, std::ios_base::openmode mode = std::ios_base::in | std::ios_base::out) : basic_ios_t(), base_t(0), m_buf(param, mode) { basic_ios_t::init(&m_buf); } ~basic_vectorstream(){} public: //Returns the address of the stored stream buffer. basic_vectorbuf<CharVector, CharTraits>* rdbuf() const { return const_cast<basic_vectorbuf<CharVector, CharTraits>*>(&m_buf); } //!Swaps the underlying vector with the passed vector. //!This function resets the read/write position in the stream. //!Does not throw. void swap_vector(vector_type &vect) { m_buf.swap_vector(vect); } //!Returns a const reference to the internal vector. //!Does not throw. const vector_type &vector() const { return m_buf.vector(); } //!Calls reserve() method of the internal vector. //!Resets the stream to the first position. //!Throws if the internals vector's reserve throws. void reserve(typename vector_type::size_type size) { m_buf.reserve(size); } //!Calls clear() method of the internal vector. //!Resets the stream to the first position. void clear() { m_buf.clear(); } /// @cond private: basic_vectorbuf<CharVector, CharTraits> m_buf; /// @endcond }; //Some typedefs to simplify usage //! //!typedef basic_vectorbuf<std::vector<char> > vectorbuf; //!typedef basic_vectorstream<std::vector<char> > vectorstream; //!typedef basic_ivectorstream<std::vector<char> > ivectorstream; //!typedef basic_ovectorstream<std::vector<char> > ovectorstream; //! //!typedef basic_vectorbuf<std::vector<wchar_t> > wvectorbuf; //!typedef basic_vectorstream<std::vector<wchar_t> > wvectorstream; //!typedef basic_ivectorstream<std::vector<wchar_t> > wivectorstream; //!typedef basic_ovectorstream<std::vector<wchar_t> > wovectorstream; }} //namespace boost { namespace interprocess { #include <boost/interprocess/detail/config_end.hpp> #endif /* BOOST_INTERPROCESS_VECTORSTREAM_HPP */