123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168 |
- // (C) Copyright 2008 CodeRage, LLC (turkanis at coderage dot com)
- // (C) Copyright 2003-2007 Jonathan Turkanis
- // 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/iostreams for documentation.
- #ifndef BOOST_IOSTREAMS_AGGREGATE_FILTER_HPP_INCLUDED
- #define BOOST_IOSTREAMS_AGGREGATE_FILTER_HPP_INCLUDED
- #if defined(_MSC_VER)
- # pragma once
- #endif
- #include <algorithm> // copy, min.
- #include <boost/assert.hpp>
- #include <iterator> // back_inserter
- #include <vector>
- #include <boost/iostreams/constants.hpp> // default_device_buffer_size
- #include <boost/iostreams/categories.hpp>
- #include <boost/iostreams/detail/char_traits.hpp>
- #include <boost/iostreams/detail/ios.hpp> // openmode, streamsize.
- #include <boost/iostreams/pipeline.hpp>
- #include <boost/iostreams/read.hpp> // check_eof
- #include <boost/iostreams/write.hpp>
- #include <boost/mpl/bool.hpp>
- #include <boost/type_traits/is_convertible.hpp>
- // Must come last.
- #include <boost/iostreams/detail/config/disable_warnings.hpp> // MSVC.
- namespace boost { namespace iostreams {
- //
- // Template name: aggregate_filter.
- // Template parameters:
- // Ch - The character type.
- // Alloc - The allocator type.
- // Description: Utility for defining DualUseFilters which filter an
- // entire stream at once. To use, override the protected virtual
- // member do_filter.
- // Note: This filter should not be copied while it is in use.
- //
- template<typename Ch, typename Alloc = std::allocator<Ch> >
- class aggregate_filter {
- public:
- typedef Ch char_type;
- struct category
- : dual_use,
- filter_tag,
- multichar_tag,
- closable_tag
- { };
- aggregate_filter() : ptr_(0), state_(0) { }
- virtual ~aggregate_filter() { }
- template<typename Source>
- std::streamsize read(Source& src, char_type* s, std::streamsize n)
- {
- using namespace std;
- BOOST_ASSERT(!(state_ & f_write));
- state_ |= f_read;
- if (!(state_ & f_eof))
- do_read(src);
- std::streamsize amt =
- (std::min)(n, static_cast<std::streamsize>(data_.size() - ptr_));
- if (amt) {
- BOOST_IOSTREAMS_CHAR_TRAITS(char_type)::copy(s, &data_[ptr_], amt);
- ptr_ += amt;
- }
- return detail::check_eof(amt);
- }
- template<typename Sink>
- std::streamsize write(Sink&, const char_type* s, std::streamsize n)
- {
- BOOST_ASSERT(!(state_ & f_read));
- state_ |= f_write;
- data_.insert(data_.end(), s, s + n);
- return n;
- }
- template<typename Sink>
- void close(Sink& sink, BOOST_IOS::openmode which)
- {
- if ((state_ & f_read) != 0 && which == BOOST_IOS::in)
- close_impl();
- if ((state_ & f_write) != 0 && which == BOOST_IOS::out) {
- try {
- vector_type filtered;
- do_filter(data_, filtered);
- do_write(
- sink, &filtered[0],
- static_cast<std::streamsize>(filtered.size())
- );
- } catch (...) {
- close_impl();
- throw;
- }
- close_impl();
- }
- }
- protected:
- typedef std::vector<Ch, Alloc> vector_type;
- typedef typename vector_type::size_type size_type;
- private:
- virtual void do_filter(const vector_type& src, vector_type& dest) = 0;
- virtual void do_close() { }
- template<typename Source>
- void do_read(Source& src)
- {
- using std::streamsize;
- vector_type data;
- while (true) {
- const std::streamsize size = default_device_buffer_size;
- Ch buf[size];
- std::streamsize amt;
- if ((amt = boost::iostreams::read(src, buf, size)) == -1)
- break;
- data.insert(data.end(), buf, buf + amt);
- }
- do_filter(data, data_);
- state_ |= f_eof;
- }
- template<typename Sink>
- void do_write(Sink& sink, const char_type* s, std::streamsize n)
- {
- typedef typename iostreams::category_of<Sink>::type category;
- typedef is_convertible<category, output> can_write;
- do_write(sink, s, n, can_write());
- }
- template<typename Sink>
- void do_write(Sink& sink, const char_type* s, std::streamsize n, mpl::true_)
- { iostreams::write(sink, s, n); }
- template<typename Sink>
- void do_write(Sink&, const char_type*, std::streamsize, mpl::false_) { }
- void close_impl()
- {
- data_.clear();
- ptr_ = 0;
- state_ = 0;
- do_close();
- }
- enum flag_type {
- f_read = 1,
- f_write = f_read << 1,
- f_eof = f_write << 1
- };
- // Note: typically will not be copied while vector contains data.
- vector_type data_;
- size_type ptr_;
- int state_;
- };
- BOOST_IOSTREAMS_PIPABLE(aggregate_filter, 1)
- } } // End namespaces iostreams, boost.
- #include <boost/iostreams/detail/config/enable_warnings.hpp> // MSVC.
- #endif // #ifndef BOOST_IOSTREAMS_AGGREGATE_FILTER_HPP_INCLUDED
|