mirror of
https://git.in.rschanz.org/ryan77627/guix.git
synced 2024-12-27 14:52:05 -05:00
247 lines
6.5 KiB
C++
247 lines
6.5 KiB
C++
// -*- C++ -*-
|
|
// Boost general library 'format' ---------------------------
|
|
// See http://www.boost.org for updates, documentation, and revision history.
|
|
|
|
// (C) Samuel Krempp 2001
|
|
// krempp@crans.ens-cachan.fr
|
|
// Permission to copy, use, modify, sell and
|
|
// distribute this software is granted provided this copyright notice appears
|
|
// in all copies. This software is provided "as is" without express or implied
|
|
// warranty, and with no claim as to its suitability for any purpose.
|
|
|
|
// ideas taken from Rüdiger Loos's format class
|
|
// and Karl Nelson's ofstream
|
|
|
|
// ----------------------------------------------------------------------------
|
|
// feed_args.hpp : functions for processing each argument
|
|
// (feed, feed_manip, and distribute)
|
|
// ----------------------------------------------------------------------------
|
|
|
|
|
|
#ifndef BOOST_FORMAT_FEED_ARGS_HPP
|
|
#define BOOST_FORMAT_FEED_ARGS_HPP
|
|
|
|
#include "boost/format/format_class.hpp"
|
|
#include "boost/format/group.hpp"
|
|
|
|
#include "boost/throw_exception.hpp"
|
|
|
|
namespace boost {
|
|
namespace io {
|
|
namespace detail {
|
|
namespace {
|
|
|
|
inline
|
|
void empty_buf(BOOST_IO_STD ostringstream & os) {
|
|
static const std::string emptyStr;
|
|
os.str(emptyStr);
|
|
}
|
|
|
|
void do_pad( std::string & s,
|
|
std::streamsize w,
|
|
const char c,
|
|
std::ios::fmtflags f,
|
|
bool center)
|
|
// applies centered / left / right padding to the string s.
|
|
// Effects : string s is padded.
|
|
{
|
|
std::streamsize n=w-s.size();
|
|
if(n<=0) {
|
|
return;
|
|
}
|
|
if(center)
|
|
{
|
|
s.reserve(w); // allocate once for the 2 inserts
|
|
const std::streamsize n1 = n /2, n0 = n - n1;
|
|
s.insert(s.begin(), n0, c);
|
|
s.append(n1, c);
|
|
}
|
|
else
|
|
{
|
|
if(f & std::ios::left) {
|
|
s.append(n, c);
|
|
}
|
|
else {
|
|
s.insert(s.begin(), n, c);
|
|
}
|
|
}
|
|
} // -do_pad(..)
|
|
|
|
|
|
template<class T> inline
|
|
void put_head(BOOST_IO_STD ostream& , const T& ) {
|
|
}
|
|
|
|
template<class T> inline
|
|
void put_head( BOOST_IO_STD ostream& os, const group1<T>& x ) {
|
|
os << group_head(x.a1_); // send the first N-1 items, not the last
|
|
}
|
|
|
|
template<class T> inline
|
|
void put_last( BOOST_IO_STD ostream& os, const T& x ) {
|
|
os << x ;
|
|
}
|
|
|
|
template<class T> inline
|
|
void put_last( BOOST_IO_STD ostream& os, const group1<T>& x ) {
|
|
os << group_last(x.a1_); // this selects the last element
|
|
}
|
|
|
|
#ifndef BOOST_NO_OVERLOAD_FOR_NON_CONST
|
|
template<class T> inline
|
|
void put_head( BOOST_IO_STD ostream& , T& ) {
|
|
}
|
|
|
|
template<class T> inline
|
|
void put_last( BOOST_IO_STD ostream& os, T& x ) {
|
|
os << x ;
|
|
}
|
|
#endif
|
|
|
|
|
|
|
|
|
|
template<class T>
|
|
void put( T x,
|
|
const format_item& specs,
|
|
std::string & res,
|
|
BOOST_IO_STD ostringstream& oss_ )
|
|
{
|
|
// does the actual conversion of x, with given params, into a string
|
|
// using the *supplied* strinstream. (the stream state is important)
|
|
|
|
typedef std::string string_t;
|
|
typedef format_item format_item_t;
|
|
|
|
stream_format_state prev_state(oss_);
|
|
|
|
specs.state_.apply_on(oss_);
|
|
|
|
// in case x is a group, apply the manip part of it,
|
|
// in order to find width
|
|
put_head( oss_, x );
|
|
empty_buf( oss_);
|
|
|
|
const std::streamsize w=oss_.width();
|
|
const std::ios::fmtflags fl=oss_.flags();
|
|
const bool internal = (fl & std::ios::internal) != 0;
|
|
const bool two_stepped_padding = internal
|
|
&& ! ( specs.pad_scheme_ & format_item_t::spacepad )
|
|
&& specs.truncate_ < 0 ;
|
|
|
|
|
|
if(! two_stepped_padding)
|
|
{
|
|
if(w>0) // handle simple padding via do_pad, not natively in stream
|
|
oss_.width(0);
|
|
put_last( oss_, x);
|
|
res = oss_.str();
|
|
|
|
if (specs.truncate_ >= 0)
|
|
res.erase(specs.truncate_);
|
|
|
|
// complex pads :
|
|
if(specs.pad_scheme_ & format_item_t::spacepad)
|
|
{
|
|
if( res.size()==0 || ( res[0]!='+' && res[0]!='-' ))
|
|
{
|
|
res.insert(res.begin(), 1, ' '); // insert 1 space at pos 0
|
|
}
|
|
}
|
|
if(w > 0) // need do_pad
|
|
{
|
|
do_pad(res,w,oss_.fill(), fl, (specs.pad_scheme_ & format_item_t::centered) !=0 );
|
|
}
|
|
}
|
|
else // 2-stepped padding
|
|
{
|
|
put_last( oss_, x); // oss_.width() may result in padding.
|
|
res = oss_.str();
|
|
|
|
if (specs.truncate_ >= 0)
|
|
res.erase(specs.truncate_);
|
|
|
|
if( res.size() - w > 0)
|
|
{ // 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.
|
|
empty_buf( oss_);
|
|
oss_.width(0);
|
|
put_last(oss_, x );
|
|
string_t tmp = oss_.str(); // minimal-length output
|
|
std::streamsize d;
|
|
if( (d=w - tmp.size()) <=0 )
|
|
{
|
|
// minimal length is already >= w, so no padding (cool!)
|
|
res.swap(tmp);
|
|
}
|
|
else
|
|
{ // hum.. we need to pad (it was necessarily multi-output)
|
|
typedef typename string_t::size_type size_type;
|
|
size_type i = 0;
|
|
while( i<tmp.size() && tmp[i] == res[i] ) // find where we should pad.
|
|
++i;
|
|
tmp.insert(i, static_cast<size_type>( d ), oss_.fill());
|
|
res.swap( tmp );
|
|
}
|
|
}
|
|
else
|
|
{ // okay, only one thing was printed and padded, so res is fine.
|
|
}
|
|
}
|
|
|
|
prev_state.apply_on(oss_);
|
|
empty_buf( oss_);
|
|
oss_.clear();
|
|
} // end- put(..)
|
|
|
|
|
|
} // local namespace
|
|
|
|
|
|
|
|
|
|
|
|
template<class T>
|
|
void distribute(basic_format& 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()); // too many variables have been supplied !
|
|
else return;
|
|
}
|
|
for(unsigned long i=0; i < self.items_.size(); ++i)
|
|
{
|
|
if(self.items_[i].argN_ == self.cur_arg_)
|
|
{
|
|
put<T> (x, self.items_[i], self.items_[i].res_, self.oss_ );
|
|
}
|
|
}
|
|
}
|
|
|
|
template<class T>
|
|
basic_format& feed(basic_format& self, T x)
|
|
{
|
|
if(self.dumped_) self.clear();
|
|
distribute<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_;
|
|
}
|
|
|
|
// this arg is finished, reset the stream's format state
|
|
self.state0_.apply_on(self.oss_);
|
|
return self;
|
|
}
|
|
|
|
|
|
} // namespace detail
|
|
} // namespace io
|
|
} // namespace boost
|
|
|
|
|
|
#endif // BOOST_FORMAT_FEED_ARGS_HPP
|