506 lines
19 KiB
C++
506 lines
19 KiB
C++
// ----------------------------------------------------------------------------
|
|
// parsing.hpp : implementation of the parsing member functions
|
|
// ( parse, parse_printf_directive)
|
|
// ----------------------------------------------------------------------------
|
|
|
|
// 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_PARSING_HPP
|
|
#define BOOST_FORMAT_PARSING_HPP
|
|
|
|
|
|
#include <boost/format/format_class.hpp>
|
|
#include <boost/format/exceptions.hpp>
|
|
#include <boost/throw_exception.hpp>
|
|
#include <boost/assert.hpp>
|
|
#include <boost/config.hpp>
|
|
|
|
|
|
namespace boost {
|
|
namespace io {
|
|
namespace detail {
|
|
|
|
#if defined(BOOST_NO_STD_LOCALE)
|
|
// streams will be used for narrow / widen. but these methods are not const
|
|
template<class T>
|
|
T& const_or_not(const T& x) {
|
|
return const_cast<T&> (x);
|
|
}
|
|
#else
|
|
template<class T>
|
|
const T& const_or_not(const T& x) {
|
|
return x;
|
|
}
|
|
#endif
|
|
|
|
template<class Ch, class Facet> inline
|
|
char wrap_narrow(const Facet& fac, Ch c, char deflt) {
|
|
return const_or_not(fac).narrow(c, deflt);
|
|
}
|
|
|
|
template<class Ch, class Facet> inline
|
|
bool wrap_isdigit(const Facet& fac, Ch c) {
|
|
#if ! defined( BOOST_NO_LOCALE_ISDIGIT )
|
|
return fac.is(std::ctype<Ch>::digit, c);
|
|
# else
|
|
(void) fac; // remove "unused parameter" warning
|
|
using namespace std;
|
|
return isdigit(c) != 0;
|
|
#endif
|
|
}
|
|
|
|
template<class Iter, class Facet>
|
|
Iter wrap_scan_notdigit(const Facet & fac, Iter beg, Iter end) {
|
|
using namespace std;
|
|
for( ; beg!=end && wrap_isdigit(fac, *beg); ++beg) ;
|
|
return beg;
|
|
}
|
|
|
|
|
|
// Input : [start, last) iterators range and a
|
|
// a Facet to use its widen/narrow member function
|
|
// Effects : read sequence and convert digits into integral n, of type Res
|
|
// Returns : n
|
|
template<class Res, class Iter, class Facet>
|
|
Iter str2int (const Iter & start, const Iter & last, Res & res,
|
|
const Facet& fac)
|
|
{
|
|
using namespace std;
|
|
Iter it;
|
|
res=0;
|
|
for(it=start; it != last && wrap_isdigit(fac, *it); ++it ) {
|
|
char cur_ch = wrap_narrow(fac, *it, 0); // cant fail.
|
|
res *= 10;
|
|
res += cur_ch - '0'; // 22.2.1.1.2.13 of the C++ standard
|
|
}
|
|
return it;
|
|
}
|
|
|
|
// skip printf's "asterisk-fields" directives in the format-string buf
|
|
// Input : char string, with starting index *pos_p
|
|
// a Facet merely to use its widen/narrow member function
|
|
// Effects : advance *pos_p by skipping printf's asterisk fields.
|
|
// Returns : nothing
|
|
template<class Iter, class Facet>
|
|
Iter skip_asterisk(Iter start, Iter last, const Facet& fac)
|
|
{
|
|
using namespace std;
|
|
++ start;
|
|
start = wrap_scan_notdigit(fac, start, last);
|
|
if(start!=last && *start== const_or_not(fac).widen( '$') )
|
|
++start;
|
|
return start;
|
|
}
|
|
|
|
|
|
// auxiliary func called by parse_printf_directive
|
|
// for centralising error handling
|
|
// it either throws if user sets the corresponding flag, or does nothing.
|
|
inline void maybe_throw_exception(unsigned char exceptions,
|
|
std::size_t pos, std::size_t size)
|
|
{
|
|
if(exceptions & io::bad_format_string_bit)
|
|
boost::throw_exception(io::bad_format_string(pos, size) );
|
|
}
|
|
|
|
|
|
// Input: the position of a printf-directive in the format-string
|
|
// a basic_ios& merely to use its widen/narrow member function
|
|
// a bitset'exceptions' telling whether to throw exceptions on errors.
|
|
// Returns:
|
|
// true if parse succeeded (ignore some errors if exceptions disabled)
|
|
// false if it failed so bad that the directive should be printed verbatim
|
|
// Effects:
|
|
// start is incremented so that *start is the first char after
|
|
// this directive
|
|
// *fpar is set with the parameters read in the directive
|
|
template<class Ch, class Tr, class Alloc, class Iter, class Facet>
|
|
bool parse_printf_directive(Iter & start, const Iter& last,
|
|
detail::format_item<Ch, Tr, Alloc> * fpar,
|
|
const Facet& fac,
|
|
std::size_t offset, unsigned char exceptions)
|
|
{
|
|
typedef typename basic_format<Ch, Tr, Alloc>::format_item_t format_item_t;
|
|
|
|
fpar->argN_ = format_item_t::argN_no_posit; // if no positional-directive
|
|
bool precision_set = false;
|
|
bool in_brackets=false;
|
|
Iter start0 = start;
|
|
std::size_t fstring_size = last-start0+offset;
|
|
|
|
if(start>= last) { // empty directive : this is a trailing %
|
|
maybe_throw_exception(exceptions, start-start0 + offset, fstring_size);
|
|
return false;
|
|
}
|
|
|
|
if(*start== const_or_not(fac).widen( '|')) {
|
|
in_brackets=true;
|
|
if( ++start >= last ) {
|
|
maybe_throw_exception(exceptions, start-start0 + offset, fstring_size);
|
|
return false;
|
|
}
|
|
}
|
|
|
|
// the flag '0' would be picked as a digit for argument order, but here it's a flag :
|
|
if(*start== const_or_not(fac).widen( '0'))
|
|
goto parse_flags;
|
|
|
|
// handle argument order (%2$d) or possibly width specification: %2d
|
|
if(wrap_isdigit(fac, *start)) {
|
|
int n;
|
|
start = str2int(start, last, n, fac);
|
|
if( start >= last ) {
|
|
maybe_throw_exception(exceptions, start-start0+offset, fstring_size);
|
|
return false;
|
|
}
|
|
|
|
// %N% case : this is already the end of the directive
|
|
if( *start == const_or_not(fac).widen( '%') ) {
|
|
fpar->argN_ = n-1;
|
|
++start;
|
|
if( in_brackets)
|
|
maybe_throw_exception(exceptions, start-start0+offset, fstring_size);
|
|
// but don't return. maybe "%" was used in lieu of '$', so we go on.
|
|
else
|
|
return true;
|
|
}
|
|
|
|
if ( *start== const_or_not(fac).widen( '$') ) {
|
|
fpar->argN_ = n-1;
|
|
++start;
|
|
}
|
|
else {
|
|
// non-positionnal directive
|
|
fpar->fmtstate_.width_ = n;
|
|
fpar->argN_ = format_item_t::argN_no_posit;
|
|
goto parse_precision;
|
|
}
|
|
}
|
|
|
|
parse_flags:
|
|
// handle flags
|
|
while ( start != last) { // as long as char is one of + - = _ # 0 l h or ' '
|
|
// misc switches
|
|
switch ( wrap_narrow(fac, *start, 0)) {
|
|
case '\'' : break; // no effect yet. (painful to implement)
|
|
case 'l':
|
|
case 'h': // short/long modifier : for printf-comaptibility (no action needed)
|
|
break;
|
|
case '-':
|
|
fpar->fmtstate_.flags_ |= std::ios_base::left;
|
|
break;
|
|
case '=':
|
|
fpar->pad_scheme_ |= format_item_t::centered;
|
|
break;
|
|
case '_':
|
|
fpar->fmtstate_.flags_ |= std::ios_base::internal;
|
|
break;
|
|
case ' ':
|
|
fpar->pad_scheme_ |= format_item_t::spacepad;
|
|
break;
|
|
case '+':
|
|
fpar->fmtstate_.flags_ |= std::ios_base::showpos;
|
|
break;
|
|
case '0':
|
|
fpar->pad_scheme_ |= format_item_t::zeropad;
|
|
// need to know alignment before really setting flags,
|
|
// so just add 'zeropad' flag for now, it will be processed later.
|
|
break;
|
|
case '#':
|
|
fpar->fmtstate_.flags_ |= std::ios_base::showpoint | std::ios_base::showbase;
|
|
break;
|
|
default:
|
|
goto parse_width;
|
|
}
|
|
++start;
|
|
} // loop on flag.
|
|
|
|
if( start>=last) {
|
|
maybe_throw_exception(exceptions, start-start0+offset, fstring_size);
|
|
return true;
|
|
}
|
|
parse_width:
|
|
// handle width spec
|
|
// first skip 'asterisk fields' : *, or *N$
|
|
if(*start == const_or_not(fac).widen( '*') )
|
|
start = skip_asterisk(start, last, fac);
|
|
if(start!=last && wrap_isdigit(fac, *start))
|
|
start = str2int(start, last, fpar->fmtstate_.width_, fac);
|
|
|
|
parse_precision:
|
|
if( start>= last) {
|
|
maybe_throw_exception(exceptions, start-start0+offset, fstring_size);
|
|
return true;
|
|
}
|
|
// handle precision spec
|
|
if (*start== const_or_not(fac).widen( '.')) {
|
|
++start;
|
|
if(start != last && *start == const_or_not(fac).widen( '*') )
|
|
start = skip_asterisk(start, last, fac);
|
|
if(start != last && wrap_isdigit(fac, *start)) {
|
|
start = str2int(start, last, fpar->fmtstate_.precision_, fac);
|
|
precision_set = true;
|
|
}
|
|
else
|
|
fpar->fmtstate_.precision_ =0;
|
|
}
|
|
|
|
// handle formatting-type flags :
|
|
while( start != last && ( *start== const_or_not(fac).widen( 'l')
|
|
|| *start== const_or_not(fac).widen( 'L')
|
|
|| *start== const_or_not(fac).widen( 'h')) )
|
|
++start;
|
|
if( start>=last) {
|
|
maybe_throw_exception(exceptions, start-start0+offset, fstring_size);
|
|
return true;
|
|
}
|
|
|
|
if( in_brackets && *start== const_or_not(fac).widen( '|') ) {
|
|
++start;
|
|
return true;
|
|
}
|
|
switch ( wrap_narrow(fac, *start, 0) ) {
|
|
case 'X':
|
|
fpar->fmtstate_.flags_ |= std::ios_base::uppercase;
|
|
BOOST_FALLTHROUGH;
|
|
case 'p': // pointer => set hex.
|
|
case 'x':
|
|
fpar->fmtstate_.flags_ &= ~std::ios_base::basefield;
|
|
fpar->fmtstate_.flags_ |= std::ios_base::hex;
|
|
break;
|
|
|
|
case 'o':
|
|
fpar->fmtstate_.flags_ &= ~std::ios_base::basefield;
|
|
fpar->fmtstate_.flags_ |= std::ios_base::oct;
|
|
break;
|
|
|
|
case 'E':
|
|
fpar->fmtstate_.flags_ |= std::ios_base::uppercase;
|
|
BOOST_FALLTHROUGH;
|
|
case 'e':
|
|
fpar->fmtstate_.flags_ &= ~std::ios_base::floatfield;
|
|
fpar->fmtstate_.flags_ |= std::ios_base::scientific;
|
|
|
|
fpar->fmtstate_.flags_ &= ~std::ios_base::basefield;
|
|
fpar->fmtstate_.flags_ |= std::ios_base::dec;
|
|
break;
|
|
|
|
case 'f':
|
|
fpar->fmtstate_.flags_ &= ~std::ios_base::floatfield;
|
|
fpar->fmtstate_.flags_ |= std::ios_base::fixed;
|
|
BOOST_FALLTHROUGH;
|
|
case 'u':
|
|
case 'd':
|
|
case 'i':
|
|
fpar->fmtstate_.flags_ &= ~std::ios_base::basefield;
|
|
fpar->fmtstate_.flags_ |= std::ios_base::dec;
|
|
break;
|
|
|
|
case 'T':
|
|
++start;
|
|
if( start >= last)
|
|
maybe_throw_exception(exceptions, start-start0+offset, fstring_size);
|
|
else
|
|
fpar->fmtstate_.fill_ = *start;
|
|
fpar->pad_scheme_ |= format_item_t::tabulation;
|
|
fpar->argN_ = format_item_t::argN_tabulation;
|
|
break;
|
|
case 't':
|
|
fpar->fmtstate_.fill_ = const_or_not(fac).widen( ' ');
|
|
fpar->pad_scheme_ |= format_item_t::tabulation;
|
|
fpar->argN_ = format_item_t::argN_tabulation;
|
|
break;
|
|
|
|
case 'G':
|
|
fpar->fmtstate_.flags_ |= std::ios_base::uppercase;
|
|
break;
|
|
case 'g': // 'g' conversion is default for floats.
|
|
fpar->fmtstate_.flags_ &= ~std::ios_base::basefield;
|
|
fpar->fmtstate_.flags_ |= std::ios_base::dec;
|
|
|
|
// CLEAR all floatield flags, so stream will CHOOSE
|
|
fpar->fmtstate_.flags_ &= ~std::ios_base::floatfield;
|
|
break;
|
|
|
|
case 'C':
|
|
case 'c':
|
|
fpar->truncate_ = 1;
|
|
break;
|
|
case 'S':
|
|
case 's':
|
|
if(precision_set) // handle truncation manually, with own parameter.
|
|
fpar->truncate_ = fpar->fmtstate_.precision_;
|
|
fpar->fmtstate_.precision_ = 6; // default stream precision.
|
|
break;
|
|
case 'n' :
|
|
fpar->argN_ = format_item_t::argN_ignored;
|
|
break;
|
|
default:
|
|
maybe_throw_exception(exceptions, start-start0+offset, fstring_size);
|
|
}
|
|
++start;
|
|
|
|
if( in_brackets ) {
|
|
if( start != last && *start== const_or_not(fac).widen( '|') ) {
|
|
++start;
|
|
return true;
|
|
}
|
|
else maybe_throw_exception(exceptions, start-start0+offset, fstring_size);
|
|
}
|
|
return true;
|
|
}
|
|
// -end parse_printf_directive()
|
|
|
|
template<class String, class Facet>
|
|
int upper_bound_from_fstring(const String& buf,
|
|
const typename String::value_type arg_mark,
|
|
const Facet& fac,
|
|
unsigned char exceptions)
|
|
{
|
|
// quick-parsing of the format-string to count arguments mark (arg_mark, '%')
|
|
// returns : upper bound on the number of format items in the format strings
|
|
using namespace boost::io;
|
|
typename String::size_type i1=0;
|
|
int num_items=0;
|
|
while( (i1=buf.find(arg_mark,i1)) != String::npos ) {
|
|
if( i1+1 >= buf.size() ) {
|
|
if(exceptions & bad_format_string_bit)
|
|
boost::throw_exception(bad_format_string(i1, buf.size() )); // must not end in ".. %"
|
|
else {
|
|
++num_items;
|
|
break;
|
|
}
|
|
}
|
|
if(buf[i1+1] == buf[i1] ) {// escaped "%%"
|
|
i1+=2; continue;
|
|
}
|
|
|
|
++i1;
|
|
// in case of %N% directives, dont count it double (wastes allocations..) :
|
|
i1 = detail::wrap_scan_notdigit(fac, buf.begin()+i1, buf.end()) - buf.begin();
|
|
if( i1 < buf.size() && buf[i1] == arg_mark )
|
|
++i1;
|
|
++num_items;
|
|
}
|
|
return num_items;
|
|
}
|
|
template<class String> inline
|
|
void append_string(String& dst, const String& src,
|
|
const typename String::size_type beg,
|
|
const typename String::size_type end) {
|
|
dst.append(src.begin()+beg, src.begin()+end);
|
|
}
|
|
|
|
} // detail namespace
|
|
} // io namespace
|
|
|
|
|
|
|
|
// -----------------------------------------------
|
|
// format :: parse(..)
|
|
|
|
template<class Ch, class Tr, class Alloc>
|
|
basic_format<Ch, Tr, Alloc>& basic_format<Ch, Tr, Alloc>::
|
|
parse (const string_type& buf) {
|
|
// parse the format-string
|
|
using namespace std;
|
|
#if !defined(BOOST_NO_STD_LOCALE)
|
|
const std::ctype<Ch> & fac = BOOST_USE_FACET( std::ctype<Ch>, getloc());
|
|
#else
|
|
io::basic_oaltstringstream<Ch, Tr, Alloc> fac;
|
|
//has widen and narrow even on compilers without locale
|
|
#endif
|
|
|
|
const Ch arg_mark = io::detail::const_or_not(fac).widen( '%');
|
|
bool ordered_args=true;
|
|
int max_argN=-1;
|
|
|
|
// A: find upper_bound on num_items and allocates arrays
|
|
int num_items = io::detail::upper_bound_from_fstring(buf, arg_mark, fac, exceptions());
|
|
make_or_reuse_data(num_items);
|
|
|
|
// B: Now the real parsing of the format string :
|
|
num_items=0;
|
|
typename string_type::size_type i0=0, i1=0;
|
|
typename string_type::const_iterator it;
|
|
bool special_things=false;
|
|
int cur_item=0;
|
|
while( (i1=buf.find(arg_mark,i1)) != string_type::npos ) {
|
|
string_type & piece = (cur_item==0) ? prefix_ : items_[cur_item-1].appendix_;
|
|
if( buf[i1+1] == buf[i1] ) { // escaped mark, '%%'
|
|
io::detail::append_string(piece, buf, i0, i1+1);
|
|
i1+=2; i0=i1;
|
|
continue;
|
|
}
|
|
BOOST_ASSERT( static_cast<unsigned int>(cur_item) < items_.size() || cur_item==0);
|
|
|
|
if(i1!=i0) {
|
|
io::detail::append_string(piece, buf, i0, i1);
|
|
i0=i1;
|
|
}
|
|
++i1;
|
|
it = buf.begin()+i1;
|
|
bool parse_ok = io::detail::parse_printf_directive(
|
|
it, buf.end(), &items_[cur_item], fac, i1, exceptions());
|
|
i1 = it - buf.begin();
|
|
if( ! parse_ok ) // the directive will be printed verbatim
|
|
continue;
|
|
i0=i1;
|
|
items_[cur_item].compute_states(); // process complex options, like zeropad, into params
|
|
|
|
int argN=items_[cur_item].argN_;
|
|
if(argN == format_item_t::argN_ignored)
|
|
continue;
|
|
if(argN ==format_item_t::argN_no_posit)
|
|
ordered_args=false;
|
|
else if(argN == format_item_t::argN_tabulation) special_things=true;
|
|
else if(argN > max_argN) max_argN = argN;
|
|
++num_items;
|
|
++cur_item;
|
|
} // loop on %'s
|
|
BOOST_ASSERT(cur_item == num_items);
|
|
|
|
// store the final piece of string
|
|
{
|
|
string_type & piece = (cur_item==0) ? prefix_ : items_[cur_item-1].appendix_;
|
|
io::detail::append_string(piece, buf, i0, buf.size());
|
|
}
|
|
|
|
if( !ordered_args) {
|
|
if(max_argN >= 0 ) { // dont mix positional with non-positionnal directives
|
|
if(exceptions() & io::bad_format_string_bit)
|
|
boost::throw_exception(
|
|
io::bad_format_string(static_cast<std::size_t>(max_argN), 0));
|
|
// else do nothing. => positionnal arguments are processed as non-positionnal
|
|
}
|
|
// set things like it would have been with positional directives :
|
|
int non_ordered_items = 0;
|
|
for(int i=0; i< num_items; ++i)
|
|
if(items_[i].argN_ == format_item_t::argN_no_posit) {
|
|
items_[i].argN_ = non_ordered_items;
|
|
++non_ordered_items;
|
|
}
|
|
max_argN = non_ordered_items-1;
|
|
}
|
|
|
|
// C: set some member data :
|
|
items_.resize(num_items, format_item_t(io::detail::const_or_not(fac).widen( ' ')) );
|
|
|
|
if(special_things) style_ |= special_needs;
|
|
num_args_ = max_argN + 1;
|
|
if(ordered_args) style_ |= ordered;
|
|
else style_ &= ~ordered;
|
|
return *this;
|
|
}
|
|
|
|
} // namespace boost
|
|
|
|
|
|
#endif // BOOST_FORMAT_PARSING_HPP
|