Chris@16: // ----------------------------------------------------------------------------
Chris@16: //  feed_args.hpp :  functions for processing each argument 
Chris@16: //                      (feed, feed_manip, and distribute)
Chris@16: // ----------------------------------------------------------------------------
Chris@16: 
Chris@16: //  Copyright Samuel Krempp 2003. Use, modification, and distribution are
Chris@16: //  subject to 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: //  See http://www.boost.org/libs/format for library home page
Chris@16: 
Chris@16: // ----------------------------------------------------------------------------
Chris@16: 
Chris@16: #ifndef BOOST_FORMAT_FEED_ARGS_HPP
Chris@16: #define BOOST_FORMAT_FEED_ARGS_HPP
Chris@16: 
Chris@16: #include <boost/config.hpp>
Chris@16: #include <boost/assert.hpp>
Chris@16: #include <boost/throw_exception.hpp>
Chris@16: 
Chris@16: #include <boost/format/format_class.hpp>
Chris@16: #include <boost/format/group.hpp>
Chris@16: #include <boost/format/detail/msvc_disambiguater.hpp>
Chris@16: 
Chris@16: namespace boost {
Chris@16: namespace io {
Chris@16: namespace detail {
Chris@16: 
Chris@16:     template<class Ch, class Tr, class Alloc>
Chris@16:     void mk_str( std::basic_string<Ch,Tr, Alloc> & res, 
Chris@16:                  const Ch * beg,
Chris@16:                  typename std::basic_string<Ch,Tr,Alloc>::size_type size,
Chris@16:                  std::streamsize w, 
Chris@16:                  const Ch fill_char,
Chris@16:                  std::ios_base::fmtflags f, 
Chris@16:                  const Ch prefix_space, // 0 if no space-padding
Chris@16:                  bool center) 
Chris@16:     // applies centered/left/right  padding  to the string  [beg, beg+size[
Chris@16:     // Effects : the result is placed in res.
Chris@16:     {
Chris@16:         typedef typename std::basic_string<Ch,Tr,Alloc>::size_type size_type;
Chris@16:         res.resize(0);
Chris@16:         if(w<=0 || static_cast<size_type>(w) <=size) {
Chris@16:             // no need to pad.
Chris@16:             res.reserve(size + !!prefix_space);
Chris@16:             if(prefix_space) 
Chris@16:               res.append(1, prefix_space);
Chris@16:             if (size)
Chris@16:               res.append(beg, size);
Chris@16:         }
Chris@16:         else { 
Chris@16:             std::streamsize n=static_cast<std::streamsize>(w-size-!!prefix_space);
Chris@16:             std::streamsize n_after = 0, n_before = 0; 
Chris@16:             res.reserve(static_cast<size_type>(w)); // allocate once for the 2 inserts
Chris@16:             if(center) 
Chris@16:                 n_after = n/2, n_before = n - n_after; 
Chris@16:             else 
Chris@16:                 if(f & std::ios_base::left)
Chris@16:                     n_after = n;
Chris@16:                 else
Chris@16:                     n_before = n;
Chris@16:             // now make the res string :
Chris@16:             if(n_before) res.append(static_cast<size_type>(n_before), fill_char);
Chris@16:             if(prefix_space) 
Chris@16:               res.append(1, prefix_space);
Chris@16:             if (size)  
Chris@16:               res.append(beg, size);
Chris@16:             if(n_after) res.append(static_cast<size_type>(n_after), fill_char);
Chris@16:         }
Chris@16:     } // -mk_str(..) 
Chris@16: 
Chris@16: 
Chris@101: #if BOOST_WORKAROUND(__DECCXX_VER, BOOST_TESTED_AT(60590042))
Chris@101: // __DECCXX needs to be tricked to disambiguate this simple overload..
Chris@16: // the trick is in "boost/format/msvc_disambiguater.hpp"
Chris@16:   
Chris@16:     template< class Ch, class Tr, class T> inline
Chris@16:     void put_head (BOOST_IO_STD basic_ostream<Ch, Tr> & os, const T& x ) {
Chris@16:         disambiguater<Ch, Tr, T>::put_head(os, x, 1L);
Chris@16:     }
Chris@16:     template< class Ch, class Tr, class T> inline
Chris@16:     void put_last (BOOST_IO_STD basic_ostream<Ch, Tr> & os, const T& x ) {
Chris@16:         disambiguater<Ch, Tr, T>::put_last(os, x, 1L);
Chris@16:     }
Chris@16: 
Chris@16: #else  
Chris@16: 
Chris@16:     template< class Ch, class Tr, class T> inline
Chris@16:     void put_head (BOOST_IO_STD basic_ostream<Ch, Tr> &, const T& ) {
Chris@16:     }
Chris@16: 
Chris@16:     template< class Ch, class Tr, class T> inline
Chris@16:     void put_head( BOOST_IO_STD basic_ostream<Ch, Tr> & os, const group1<T>& x ) {
Chris@16:         os << group_head(x.a1_); // send the first N-1 items, not the last
Chris@16:     }
Chris@16: 
Chris@16:     template< class Ch, class Tr, class T> inline
Chris@16:     void put_last( BOOST_IO_STD basic_ostream<Ch, Tr> & os, const T& x ) {
Chris@16:         os << x ;
Chris@16:     }
Chris@16: 
Chris@16:     template< class Ch, class Tr, class T> inline
Chris@16:     void put_last( BOOST_IO_STD basic_ostream<Ch, Tr> & os, const group1<T>& x ) {
Chris@16:         os << group_last(x.a1_); // this selects the last element
Chris@16:     }
Chris@16: 
Chris@16: #ifndef BOOST_NO_OVERLOAD_FOR_NON_CONST 
Chris@16:     template< class Ch, class Tr, class T> inline
Chris@16:     void put_head( BOOST_IO_STD basic_ostream<Ch, Tr> &, T& ) {
Chris@16:     }
Chris@16: 
Chris@16:     template< class Ch, class Tr, class T> inline
Chris@16:     void put_last( BOOST_IO_STD basic_ostream<Ch, Tr> & os, T& x) {
Chris@16:         os << x ;
Chris@16:     }
Chris@16: #endif
Chris@101: #endif  // -__DECCXX workaround
Chris@101: 
Chris@101:     template< class Ch, class Tr, class T>
Chris@101:     void call_put_head(BOOST_IO_STD basic_ostream<Ch, Tr> & os, const void* x) {
Chris@101:         put_head(os, *(typename ::boost::remove_reference<T>::type*)x);
Chris@101:     }
Chris@101: 
Chris@101:     template< class Ch, class Tr, class T>
Chris@101:     void call_put_last(BOOST_IO_STD basic_ostream<Ch, Tr> & os, const void* x) {
Chris@101:         put_last(os, *(T*)x);
Chris@101:     }
Chris@101: 
Chris@101:     template< class Ch, class Tr>
Chris@101:     struct put_holder {
Chris@101:         template<class T>
Chris@101:         put_holder(T& t)
Chris@101:           : arg(&t),
Chris@101:             put_head(&call_put_head<Ch, Tr, T>),
Chris@101:             put_last(&call_put_last<Ch, Tr, T>)
Chris@101:         {}
Chris@101:         const void* arg;
Chris@101:         void (*put_head)(BOOST_IO_STD basic_ostream<Ch, Tr> & os, const void* x);
Chris@101:         void (*put_last)(BOOST_IO_STD basic_ostream<Ch, Tr> & os, const void* x);
Chris@101:     };
Chris@101:     
Chris@101:     template< class Ch, class Tr> inline
Chris@101:     void put_head( BOOST_IO_STD basic_ostream<Ch, Tr> & os, const put_holder<Ch, Tr>& t) {
Chris@101:         t.put_head(os, t.arg);
Chris@101:     }
Chris@101:     
Chris@101:     template< class Ch, class Tr> inline
Chris@101:     void put_last( BOOST_IO_STD basic_ostream<Ch, Tr> & os, const put_holder<Ch, Tr>& t) {
Chris@101:         t.put_last(os, t.arg);
Chris@101:     }
Chris@16: 
Chris@16: 
Chris@16:     template< class Ch, class Tr, class Alloc, class T> 
Chris@16:     void put( T x, 
Chris@16:               const format_item<Ch, Tr, Alloc>& specs, 
Chris@16:               typename basic_format<Ch, Tr, Alloc>::string_type& res, 
Chris@16:               typename basic_format<Ch, Tr, Alloc>::internal_streambuf_t & buf,
Chris@16:               io::detail::locale_t *loc_p = NULL)
Chris@16:     {
Chris@16: #ifdef BOOST_MSVC
Chris@16:        // If std::min<unsigned> or std::max<unsigned> are already instantiated
Chris@16:        // at this point then we get a blizzard of warning messages when we call
Chris@16:        // those templates with std::size_t as arguments.  Weird and very annoyning...
Chris@16: #pragma warning(push)
Chris@16: #pragma warning(disable:4267)
Chris@16: #endif
Chris@16:         // does the actual conversion of x, with given params, into a string
Chris@16:         // using the supplied stringbuf.
Chris@16: 
Chris@16:         typedef typename basic_format<Ch, Tr, Alloc>::string_type   string_type;
Chris@16:         typedef typename basic_format<Ch, Tr, Alloc>::format_item_t format_item_t;
Chris@16:         typedef typename string_type::size_type size_type;
Chris@16: 
Chris@16:         basic_oaltstringstream<Ch, Tr, Alloc>  oss( &buf);
Chris@16:         specs.fmtstate_.apply_on(oss, loc_p);
Chris@16: 
Chris@16:         // the stream format state can be modified by manipulators in the argument :
Chris@16:         put_head( oss, x );
Chris@16:         // in case x is a group, apply the manip part of it, 
Chris@16:         // in order to find width
Chris@16: 
Chris@16:         const std::ios_base::fmtflags fl=oss.flags();
Chris@16:         const bool internal = (fl & std::ios_base::internal) != 0;
Chris@16:         const std::streamsize w = oss.width();
Chris@16:         const bool two_stepped_padding= internal && (w!=0);
Chris@16:       
Chris@16:         res.resize(0);
Chris@16:         if(! two_stepped_padding) {
Chris@16:             if(w>0) // handle padding via mk_str, not natively in stream 
Chris@16:                 oss.width(0);
Chris@16:             put_last( oss, x);
Chris@16:             const Ch * res_beg = buf.pbase();
Chris@16:             Ch prefix_space = 0;
Chris@16:             if(specs.pad_scheme_ & format_item_t::spacepad)
Chris@16:                 if(buf.pcount()== 0 || 
Chris@16:                    (res_beg[0] !=oss.widen('+') && res_beg[0] !=oss.widen('-')  ))
Chris@16:                     prefix_space = oss.widen(' ');
Chris@16:             size_type res_size = (std::min)(
Chris@16:                 static_cast<size_type>(specs.truncate_ - !!prefix_space), 
Chris@16:                 buf.pcount() );
Chris@16:             mk_str(res, res_beg, res_size, w, oss.fill(), fl, 
Chris@16:                    prefix_space, (specs.pad_scheme_ & format_item_t::centered) !=0 );
Chris@16:         }
Chris@16:         else  { // 2-stepped padding
Chris@16:             // internal can be implied by zeropad, or user-set.
Chris@16:             // left, right, and centered alignment overrule internal,
Chris@16:             // but spacepad or truncate might be mixed with internal (using manipulator)
Chris@16:             put_last( oss, x); // may pad
Chris@16:             const Ch * res_beg = buf.pbase();
Chris@16:             size_type res_size = buf.pcount();
Chris@16:             bool prefix_space=false;
Chris@16:             if(specs.pad_scheme_ & format_item_t::spacepad)
Chris@16:                 if(buf.pcount()== 0 || 
Chris@16:                    (res_beg[0] !=oss.widen('+') && res_beg[0] !=oss.widen('-')  ))
Chris@16:                     prefix_space = true;
Chris@16:             if(res_size == static_cast<size_type>(w) && w<=specs.truncate_ && !prefix_space) {
Chris@16:                 // okay, only one thing was printed and padded, so res is fine
Chris@16:                 res.assign(res_beg, res_size);
Chris@16:             }
Chris@16:             else { //   length w exceeded
Chris@16:                 // either it was multi-output with first output padding up all width..
Chris@16:                 // either it was one big arg and we are fine.
Chris@16:                 // Note that res_size<w is possible  (in case of bad user-defined formatting)
Chris@16:                 res.assign(res_beg, res_size);
Chris@16:                 res_beg=NULL;  // invalidate pointers.
Chris@16:                 
Chris@16:                 // make a new stream, to start re-formatting from scratch :
Chris@16:                 buf.clear_buffer();
Chris@16:                 basic_oaltstringstream<Ch, Tr, Alloc>  oss2( &buf);
Chris@16:                 specs.fmtstate_.apply_on(oss2, loc_p);
Chris@16:                 put_head( oss2, x );
Chris@16: 
Chris@16:                 oss2.width(0);
Chris@16:                 if(prefix_space)
Chris@16:                     oss2 << ' ';
Chris@16:                 put_last(oss2, x );
Chris@16:                 if(buf.pcount()==0 && specs.pad_scheme_ & format_item_t::spacepad) {
Chris@16:                     prefix_space =true;
Chris@16:                     oss2 << ' ';
Chris@16:                 }
Chris@16:                 // we now have the minimal-length output
Chris@16:                 const Ch * tmp_beg = buf.pbase();
Chris@16:                 size_type tmp_size = (std::min)(static_cast<size_type>(specs.truncate_),
Chris@16:                                                 buf.pcount() );
Chris@16:                                                     
Chris@16:                 
Chris@16:                 if(static_cast<size_type>(w) <= tmp_size) { 
Chris@16:                     // minimal length is already >= w, so no padding (cool!)
Chris@16:                         res.assign(tmp_beg, tmp_size);
Chris@16:                 }
Chris@16:                 else { // hum..  we need to pad (multi_output, or spacepad present)
Chris@16:                     //find where we should pad
Chris@16:                     size_type sz = (std::min)(res_size + (prefix_space ? 1 : 0), tmp_size);
Chris@16:                     size_type i = prefix_space;
Chris@16:                     for(; i<sz && tmp_beg[i] == res[i - (prefix_space ? 1 : 0)]; ++i) {}
Chris@16:                     if(i>=tmp_size) i=prefix_space;
Chris@16:                     res.assign(tmp_beg, i);
Chris@16:                                         std::streamsize d = w - static_cast<std::streamsize>(tmp_size);
Chris@16:                                         BOOST_ASSERT(d>0);
Chris@16:                     res.append(static_cast<size_type>( d ), oss2.fill());
Chris@16:                     res.append(tmp_beg+i, tmp_size-i);
Chris@16:                     BOOST_ASSERT(i+(tmp_size-i)+(std::max)(d,(std::streamsize)0) 
Chris@16:                                  == static_cast<size_type>(w));
Chris@16:                     BOOST_ASSERT(res.size() == static_cast<size_type>(w));
Chris@16:                 }
Chris@16:             }
Chris@16:         }
Chris@16:         buf.clear_buffer();
Chris@16: #ifdef BOOST_MSVC
Chris@16: #pragma warning(pop)
Chris@16: #endif
Chris@16:     } // end- put(..)
Chris@16: 
Chris@16: 
Chris@16:     template< class Ch, class Tr, class Alloc, class T> 
Chris@16:     void distribute (basic_format<Ch,Tr, Alloc>& self, T x) {
Chris@16:         // call put(x, ..) on every occurence of the current argument :
Chris@16:         if(self.cur_arg_ >= self.num_args_)  {
Chris@16:             if( self.exceptions() & too_many_args_bit )
Chris@16:                 boost::throw_exception(too_many_args(self.cur_arg_, self.num_args_)); 
Chris@16:             else return;
Chris@16:         }
Chris@16:         for(unsigned long i=0; i < self.items_.size(); ++i) {
Chris@16:             if(self.items_[i].argN_ == self.cur_arg_) {
Chris@16:                 put<Ch, Tr, Alloc, T> (x, self.items_[i], self.items_[i].res_, 
Chris@16:                                 self.buf_, boost::get_pointer(self.loc_) );
Chris@16:             }
Chris@16:         }
Chris@16:     }
Chris@16: 
Chris@16:     template<class Ch, class Tr, class Alloc, class T> 
Chris@16:     basic_format<Ch, Tr, Alloc>&  
Chris@101:     feed_impl (basic_format<Ch,Tr, Alloc>& self, T x) {
Chris@16:         if(self.dumped_) self.clear();
Chris@16:         distribute<Ch, Tr, Alloc, T> (self, x);
Chris@16:         ++self.cur_arg_;
Chris@16:         if(self.bound_.size() != 0) {
Chris@16:                 while( self.cur_arg_ < self.num_args_ && self.bound_[self.cur_arg_] )
Chris@16:                     ++self.cur_arg_;
Chris@16:         }
Chris@16:         return self;
Chris@16:     }
Chris@101: 
Chris@101:     template<class Ch, class Tr, class Alloc, class T> inline
Chris@101:     basic_format<Ch, Tr, Alloc>&  
Chris@101:     feed (basic_format<Ch,Tr, Alloc>& self, T x) {
Chris@101:         return feed_impl<Ch, Tr, Alloc, const put_holder<Ch, Tr>&>(self, put_holder<Ch, Tr>(x));
Chris@101:     }
Chris@16:     
Chris@16: } // namespace detail
Chris@16: } // namespace io
Chris@16: } // namespace boost
Chris@16: 
Chris@16: 
Chris@16: #endif //  BOOST_FORMAT_FEED_ARGS_HPP