| // ---------------------------------------------------------------------------- |
| // feed_args.hpp : functions for processing each argument |
| // (feed, feed_manip, and distribute) |
| // ---------------------------------------------------------------------------- |
| |
| // Copyright Samuel Krempp 2003. Use, modification, and distribution are |
| // subject to 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/format for library home page |
| |
| // ---------------------------------------------------------------------------- |
| |
| #ifndef BOOST_FORMAT_FEED_ARGS_HPP |
| #define BOOST_FORMAT_FEED_ARGS_HPP |
| |
| #include <boost/config.hpp> |
| #include <boost/assert.hpp> |
| #include <boost/throw_exception.hpp> |
| |
| #include <boost/format/format_class.hpp> |
| #include <boost/format/group.hpp> |
| #include <boost/format/detail/msvc_disambiguater.hpp> |
| |
| namespace boost { |
| namespace io { |
| namespace detail { |
| |
| template<class Ch, class Tr, class Alloc> |
| void mk_str( std::basic_string<Ch,Tr, Alloc> & res, |
| const Ch * beg, |
| typename std::basic_string<Ch,Tr,Alloc>::size_type size, |
| std::streamsize w, |
| const Ch fill_char, |
| std::ios_base::fmtflags f, |
| const Ch prefix_space, // 0 if no space-padding |
| bool center) |
| // applies centered/left/right padding to the string [beg, beg+size[ |
| // Effects : the result is placed in res. |
| { |
| typedef typename std::basic_string<Ch,Tr,Alloc>::size_type size_type; |
| res.resize(0); |
| if(w<=0 || static_cast<size_type>(w) <=size) { |
| // no need to pad. |
| res.reserve(size + !!prefix_space); |
| if(prefix_space) |
| res.append(1, prefix_space); |
| if (size) |
| res.append(beg, size); |
| } |
| else { |
| std::streamsize n=static_cast<std::streamsize>(w-size-!!prefix_space); |
| std::streamsize n_after = 0, n_before = 0; |
| res.reserve(static_cast<size_type>(w)); // allocate once for the 2 inserts |
| if(center) |
| n_after = n/2, n_before = n - n_after; |
| else |
| if(f & std::ios_base::left) |
| n_after = n; |
| else |
| n_before = n; |
| // now make the res string : |
| if(n_before) res.append(static_cast<size_type>(n_before), fill_char); |
| if(prefix_space) |
| res.append(1, prefix_space); |
| if (size) |
| res.append(beg, size); |
| if(n_after) res.append(static_cast<size_type>(n_after), fill_char); |
| } |
| } // -mk_str(..) |
| |
| |
| #if BOOST_WORKAROUND( BOOST_MSVC, <= 1300) || \ |
| BOOST_WORKAROUND(__DECCXX_VER, BOOST_TESTED_AT(60590042)) |
| // MSVC needs to be tricked to disambiguate this simple overload.. |
| // the trick is in "boost/format/msvc_disambiguater.hpp" |
| |
| template< class Ch, class Tr, class T> inline |
| void put_head (BOOST_IO_STD basic_ostream<Ch, Tr> & os, const T& x ) { |
| disambiguater<Ch, Tr, T>::put_head(os, x, 1L); |
| } |
| template< class Ch, class Tr, class T> inline |
| void put_last (BOOST_IO_STD basic_ostream<Ch, Tr> & os, const T& x ) { |
| disambiguater<Ch, Tr, T>::put_last(os, x, 1L); |
| } |
| |
| #else |
| |
| template< class Ch, class Tr, class T> inline |
| void put_head (BOOST_IO_STD basic_ostream<Ch, Tr> &, const T& ) { |
| } |
| |
| template< class Ch, class Tr, class T> inline |
| void put_head( BOOST_IO_STD basic_ostream<Ch, Tr> & os, const group1<T>& x ) { |
| os << group_head(x.a1_); // send the first N-1 items, not the last |
| } |
| |
| template< class Ch, class Tr, class T> inline |
| void put_last( BOOST_IO_STD basic_ostream<Ch, Tr> & os, const T& x ) { |
| os << x ; |
| } |
| |
| template< class Ch, class Tr, class T> inline |
| void put_last( BOOST_IO_STD basic_ostream<Ch, Tr> & os, const group1<T>& x ) { |
| os << group_last(x.a1_); // this selects the last element |
| } |
| |
| #ifndef BOOST_NO_OVERLOAD_FOR_NON_CONST |
| template< class Ch, class Tr, class T> inline |
| void put_head( BOOST_IO_STD basic_ostream<Ch, Tr> &, T& ) { |
| } |
| |
| template< class Ch, class Tr, class T> inline |
| void put_last( BOOST_IO_STD basic_ostream<Ch, Tr> & os, T& x) { |
| os << x ; |
| } |
| #endif |
| #endif // -msvc workaround |
| |
| |
| template< class Ch, class Tr, class Alloc, class T> |
| void put( T x, |
| const format_item<Ch, Tr, Alloc>& specs, |
| typename basic_format<Ch, Tr, Alloc>::string_type& res, |
| typename basic_format<Ch, Tr, Alloc>::internal_streambuf_t & buf, |
| io::detail::locale_t *loc_p = NULL) |
| { |
| #ifdef BOOST_MSVC |
| // If std::min<unsigned> or std::max<unsigned> are already instantiated |
| // at this point then we get a blizzard of warning messages when we call |
| // those templates with std::size_t as arguments. Weird and very annoyning... |
| #pragma warning(push) |
| #pragma warning(disable:4267) |
| #endif |
| // does the actual conversion of x, with given params, into a string |
| // using the supplied stringbuf. |
| |
| typedef typename basic_format<Ch, Tr, Alloc>::string_type string_type; |
| typedef typename basic_format<Ch, Tr, Alloc>::format_item_t format_item_t; |
| typedef typename string_type::size_type size_type; |
| |
| basic_oaltstringstream<Ch, Tr, Alloc> oss( &buf); |
| specs.fmtstate_.apply_on(oss, loc_p); |
| |
| // the stream format state can be modified by manipulators in the argument : |
| put_head( oss, x ); |
| // in case x is a group, apply the manip part of it, |
| // in order to find width |
| |
| const std::ios_base::fmtflags fl=oss.flags(); |
| const bool internal = (fl & std::ios_base::internal) != 0; |
| const std::streamsize w = oss.width(); |
| const bool two_stepped_padding= internal && (w!=0); |
| |
| res.resize(0); |
| if(! two_stepped_padding) { |
| if(w>0) // handle padding via mk_str, not natively in stream |
| oss.width(0); |
| put_last( oss, x); |
| const Ch * res_beg = buf.pbase(); |
| Ch prefix_space = 0; |
| if(specs.pad_scheme_ & format_item_t::spacepad) |
| if(buf.pcount()== 0 || |
| (res_beg[0] !=oss.widen('+') && res_beg[0] !=oss.widen('-') )) |
| prefix_space = oss.widen(' '); |
| size_type res_size = (std::min)( |
| static_cast<size_type>(specs.truncate_ - !!prefix_space), |
| buf.pcount() ); |
| mk_str(res, res_beg, res_size, w, oss.fill(), fl, |
| prefix_space, (specs.pad_scheme_ & format_item_t::centered) !=0 ); |
| } |
| else { // 2-stepped padding |
| // internal can be implied by zeropad, or user-set. |
| // left, right, and centered alignment overrule internal, |
| // but spacepad or truncate might be mixed with internal (using manipulator) |
| put_last( oss, x); // may pad |
| const Ch * res_beg = buf.pbase(); |
| size_type res_size = buf.pcount(); |
| bool prefix_space=false; |
| if(specs.pad_scheme_ & format_item_t::spacepad) |
| if(buf.pcount()== 0 || |
| (res_beg[0] !=oss.widen('+') && res_beg[0] !=oss.widen('-') )) |
| prefix_space = true; |
| if(res_size == static_cast<size_type>(w) && w<=specs.truncate_ && !prefix_space) { |
| // okay, only one thing was printed and padded, so res is fine |
| res.assign(res_beg, res_size); |
| } |
| else { // length w exceeded |
| // either it was multi-output with first output padding up all width.. |
| // either it was one big arg and we are fine. |
| // Note that res_size<w is possible (in case of bad user-defined formatting) |
| res.assign(res_beg, res_size); |
| res_beg=NULL; // invalidate pointers. |
| |
| // make a new stream, to start re-formatting from scratch : |
| buf.clear_buffer(); |
| basic_oaltstringstream<Ch, Tr, Alloc> oss2( &buf); |
| specs.fmtstate_.apply_on(oss2, loc_p); |
| put_head( oss2, x ); |
| |
| oss2.width(0); |
| if(prefix_space) |
| oss2 << ' '; |
| put_last(oss2, x ); |
| if(buf.pcount()==0 && specs.pad_scheme_ & format_item_t::spacepad) { |
| prefix_space =true; |
| oss2 << ' '; |
| } |
| // we now have the minimal-length output |
| const Ch * tmp_beg = buf.pbase(); |
| size_type tmp_size = (std::min)(static_cast<size_type>(specs.truncate_), |
| buf.pcount() ); |
| |
| |
| if(static_cast<size_type>(w) <= tmp_size) { |
| // minimal length is already >= w, so no padding (cool!) |
| res.assign(tmp_beg, tmp_size); |
| } |
| else { // hum.. we need to pad (multi_output, or spacepad present) |
| //find where we should pad |
| size_type sz = (std::min)(res_size + (prefix_space ? 1 : 0), tmp_size); |
| size_type i = prefix_space; |
| for(; i<sz && tmp_beg[i] == res[i - (prefix_space ? 1 : 0)]; ++i) {} |
| if(i>=tmp_size) i=prefix_space; |
| res.assign(tmp_beg, i); |
| std::streamsize d = w - static_cast<std::streamsize>(tmp_size); |
| BOOST_ASSERT(d>0); |
| res.append(static_cast<size_type>( d ), oss2.fill()); |
| res.append(tmp_beg+i, tmp_size-i); |
| BOOST_ASSERT(i+(tmp_size-i)+(std::max)(d,(std::streamsize)0) |
| == static_cast<size_type>(w)); |
| BOOST_ASSERT(res.size() == static_cast<size_type>(w)); |
| } |
| } |
| } |
| buf.clear_buffer(); |
| #ifdef BOOST_MSVC |
| #pragma warning(pop) |
| #endif |
| } // end- put(..) |
| |
| |
| template< class Ch, class Tr, class Alloc, class T> |
| void distribute (basic_format<Ch,Tr, Alloc>& self, T x) { |
| // call put(x, ..) on every occurence of the current argument : |
| if(self.cur_arg_ >= self.num_args_) { |
| if( self.exceptions() & too_many_args_bit ) |
| boost::throw_exception(too_many_args(self.cur_arg_, self.num_args_)); |
| else return; |
| } |
| for(unsigned long i=0; i < self.items_.size(); ++i) { |
| if(self.items_[i].argN_ == self.cur_arg_) { |
| put<Ch, Tr, Alloc, T> (x, self.items_[i], self.items_[i].res_, |
| self.buf_, boost::get_pointer(self.loc_) ); |
| } |
| } |
| } |
| |
| template<class Ch, class Tr, class Alloc, class T> |
| basic_format<Ch, Tr, Alloc>& |
| feed (basic_format<Ch,Tr, Alloc>& self, T x) { |
| if(self.dumped_) self.clear(); |
| distribute<Ch, Tr, Alloc, T> (self, x); |
| ++self.cur_arg_; |
| if(self.bound_.size() != 0) { |
| while( self.cur_arg_ < self.num_args_ && self.bound_[self.cur_arg_] ) |
| ++self.cur_arg_; |
| } |
| return self; |
| } |
| |
| } // namespace detail |
| } // namespace io |
| } // namespace boost |
| |
| |
| #endif // BOOST_FORMAT_FEED_ARGS_HPP |