istream_helpers

/*	Copyright (C) 2004 Garrett A. Kajmowicz

	This file is part of the uClibc++ Library.

	This library is free software; you can redistribute it and/or
	modify it under the terms of the GNU Lesser General Public
	License as published by the Free Software Foundation; either
	version 2.1 of the License, or (at your option) any later version.

	This library is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
	Lesser General Public License for more details.

	You should have received a copy of the GNU Lesser General Public
	License along with this library; if not, write to the Free Software
	Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/

#include <ios>
#include <cctype>

#include <string>

#ifndef __STD_HEADER_ISTREAM_HELPERS
#define __STD_HEADER_ISTREAM_HELPERS 1

#pragma GCC visibility push(default)

namespace std{


	/* We are making the following template class for serveral reasons.  Firstly,
	 * we want to keep the main istream code neat and tidy.  Secondly, we want it
	 * to be easy to do partial specialization of the istream code so that it can
	 * be expanded and put into the library.  This will allow us to make application
	 * code smaller at the expense of increased library size.  This is a fair
	 * trade-off when there are multiple applications being compiled.  Also, this
	 * feature will be used optionally via configuration options.  It will also
	 * allow us to keep the code bases in sync, dramatically simplifying the
	 * maintenance required.  We specialized for char because wchar and others
	 * require different scanf functions
	 */

	template <class C, class traits> _UCXXEXPORT 
		basic_string<C, traits> _readToken(basic_istream<C, traits>& stream)
	{
		basic_string<C, traits> temp;
		typename traits::int_type c;
		while(true){
			c = stream.rdbuf()->sgetc();
			if(c != traits::eof() && isspace(c) == false){
				stream.rdbuf()->sbumpc();
				temp.append(1, traits::to_char_type(c));
			}else{
				break;
			}
		}
		if (temp.size() == 0)
			stream.setstate(ios_base::eofbit|ios_base::failbit);

		return temp;
	}

	template <class C, class traits> _UCXXEXPORT 
		basic_string<C, traits> _readTokenDecimal(basic_istream<C, traits>& stream)
	{
		basic_string<C, traits> temp;
		typename traits::int_type c;
		while(true){
			c = stream.rdbuf()->sgetc();
			if(c != traits::eof() && isspace(c) == false && (
				isdigit(c) ||
				c == '.' ||
				c == ',' ||
				((c == '-' || c == '+') && temp.size() == 0) )
			){
				stream.rdbuf()->sbumpc();
				temp.append(1, traits::to_char_type(c));
			}else{
				break;
			}
		}
		if (temp.size() == 0)
			stream.setstate(ios_base::eofbit|ios_base::failbit);

		return temp;
	}

#ifdef __UCLIBCXX_EXPAND_ISTREAM_CHAR__

	template <> _UCXXEXPORT string _readToken<char, char_traits<char> >(istream & stream);

#endif


	template <class traits, class charT, class dataType> class _UCXXEXPORT __istream_readin{
	public:
		static void readin(basic_istream<charT,traits>& stream, dataType & var);
	};

	template <class traits> class _UCXXEXPORT __istream_readin<traits, char, bool>{
	public:
		inline static void readin(basic_istream<char, traits >& stream, bool & var)
		{
			basic_string<char, traits > temp;
			temp = _readToken( stream);
			if(temp == "true" || temp == "True" || temp == "TRUE" || temp == "1"){
				var = true;
			}else{
				var = false;
			}
		}
	};


	template <class traits> class _UCXXEXPORT __istream_readin<traits, char, short>{
	public:
		inline static void readin(basic_istream<char, traits >& stream, short & var)
		{
			basic_string<char, traits > temp;

			if(stream.flags() & ios_base::dec){
				temp = _readTokenDecimal( stream);
				sscanf(temp.c_str(), "%hd", &var );
			}else{
				temp = _readToken( stream);
				if( stream.flags() & ios_base::oct){
					sscanf(temp.c_str(), "%ho", (unsigned short int *)(&var) );
				}else if(stream.flags() & ios_base::hex){
					if(stream.flags() & ios_base::uppercase){
						sscanf(temp.c_str(), "%hX", (unsigned short int *)(&var) );
					}else{
						sscanf(temp.c_str(), "%hx", (unsigned short int *)(&var) );
					}
				}else{
					sscanf(temp.c_str(), "%hi", &var);
		
				}
			}
		}
	};

	template <class traits> class _UCXXEXPORT __istream_readin<traits, char, unsigned short>{
	public:
		inline static void readin(basic_istream<char, traits >& stream, unsigned short & var)
		{
			basic_string<char, traits > temp;

			if(stream.flags() & ios_base::dec){
				temp = _readTokenDecimal( stream);
				sscanf(temp.c_str(), "%hu", &var );
			}else{
				temp = _readToken( stream);
				if( stream.flags() & ios_base::oct){
					sscanf(temp.c_str(), "%ho", &var);
				}else if(stream.flags() & ios_base::hex){
					if(stream.flags() & ios_base::uppercase){
						sscanf(temp.c_str(), "%hX", &var );
					}else{
						sscanf(temp.c_str(), "%hx", &var);
					}
				}else{
					sscanf(temp.c_str(), "%hi", (signed short int*)(&var) );
				}
			}
		}
	};

	template <class traits> class _UCXXEXPORT __istream_readin<traits, char, int>{
	public:
		inline static void readin(basic_istream<char, traits >& stream, int & var)
		{
			basic_string<char, traits > temp;

			if(stream.flags() & ios_base::dec){
				temp = _readTokenDecimal( stream);
				sscanf(temp.c_str(), "%d", &var );
			}else{
				temp = _readToken( stream);
				if( stream.flags() & ios_base::oct){
					sscanf(temp.c_str(), "%o", (unsigned int *)(&var) );
				}else if(stream.flags() & ios_base::hex){
					if(stream.flags() & ios_base::uppercase){
						sscanf(temp.c_str(), "%X", (unsigned int *)(&var) );
					}else{
						sscanf(temp.c_str(), "%x", (unsigned int *)(&var) );
					}
				}else{
					sscanf(temp.c_str(), "%i", &var);
				}
			}
		}
	};

	template <class traits> class _UCXXEXPORT __istream_readin<traits, char, unsigned int>{
	public:
		inline static void readin(basic_istream<char, traits >& stream, unsigned int & var)
		{
			basic_string<char, traits > temp;

			if(stream.flags() & ios_base::dec){
				temp = _readTokenDecimal( stream);
				sscanf(temp.c_str(), "%u", &var );
			}else{
				temp = _readToken( stream);
				if( stream.flags() & ios_base::oct){
					sscanf(temp.c_str(), "%o", (unsigned int *)(&var) );
				}else if(stream.flags() & ios_base::hex){
					if(stream.flags() & ios_base::uppercase){
						sscanf(temp.c_str(), "%X", (unsigned int *)(&var) );
					}else{
						sscanf(temp.c_str(), "%x", (unsigned int *)(&var) );
					}
				}else{
					sscanf(temp.c_str(), "%i", (int *)(&var) );
				}
			}	

		}
	};


	template <class traits> class _UCXXEXPORT __istream_readin<traits, char, long int>{
	public:
		inline static void readin(basic_istream<char, traits >& stream, long int & var)
		{
			basic_string<char, traits > temp;

			if(stream.flags() & ios_base::dec){
				temp = _readTokenDecimal( stream);
				sscanf(temp.c_str(), "%ld", &var );
			}else{
				temp = _readToken( stream);
				if( stream.flags() & ios_base::oct){
					sscanf(temp.c_str(), "%lo", (unsigned long int *)(&var) );
				}else if(stream.flags() & ios_base::hex){
					if(stream.flags() & ios_base::uppercase){
						sscanf(temp.c_str(), "%lX", (unsigned long int *)(&var) );
					}else{
						sscanf(temp.c_str(), "%lx", (unsigned long int *)(&var) );
					}
				}else{
					sscanf(temp.c_str(), "%li", (long int *)(&var) );
				}
			}

		}
	};


	template <class traits> class _UCXXEXPORT __istream_readin<traits, char, unsigned long int>{
	public:
		inline static void readin(basic_istream<char, traits >& stream, unsigned long int & var)
		{
			basic_string<char, traits > temp;

			if(stream.flags() & ios_base::dec){
				temp = _readTokenDecimal( stream);
				sscanf(temp.c_str(), "%lu", &var );
			}else{
				temp = _readToken( stream);
				if( stream.flags() & ios_base::oct){
					sscanf(temp.c_str(), "%lo", &var );
				}else if(stream.flags() & ios_base::hex){
					if(stream.flags() & ios_base::uppercase){
						sscanf(temp.c_str(), "%lX", &var );
					}else{
						sscanf(temp.c_str(), "%lx", &var);
					}
				}else{
					sscanf(temp.c_str(), "%li", (long int *)(&var) );
				}
			}
		}
	};


#ifdef __UCLIBCXX_HAS_FLOATS__

	template <class traits> class _UCXXEXPORT __istream_readin<traits, char, float>{
	public:
		inline static void readin(basic_istream<char, traits >& stream, float & var)
		{
			basic_string<char, traits > temp;
			temp = _readTokenDecimal( stream);
#if defined (__AVR__) 
			var = strtod(temp.c_str(), NULL);
#else
			sscanf(temp.c_str(), "%g", &var);
#endif
			
		}
	};

	template <class traits> class _UCXXEXPORT __istream_readin<traits, char, double>{
	public:
		inline static void readin(basic_istream<char, traits >& stream, double & var)
		{
			basic_string<char, traits > temp;
			temp = _readTokenDecimal( stream);
#if defined (__AVR__)
			var = strtod(temp.c_str(), NULL);
#else			
			sscanf(temp.c_str(), "%lg", &var);
#endif			
		}
	};

	template <class traits> class _UCXXEXPORT __istream_readin<traits, char, long double>{
	public:
		inline static void readin(basic_istream<char, traits >& stream, long double & var)
		{
			basic_string<char, traits > temp;
			temp = _readTokenDecimal( stream);
#if defined (__AVR__)
			var = strtod(temp.c_str(), NULL);
#else			
			sscanf(temp.c_str(), "%Lg", &var);
#endif			
		}
	};

#endif	// ifdef __UCLIBCXX_HAS_FLOATS__

	template <class traits> class _UCXXEXPORT __istream_readin<traits, char, void*>{
	public:
		inline static void readin(basic_istream<char, traits >& stream, void* & var)
		{
			basic_string<char, traits > temp;
			temp = _readToken( stream);
			sscanf(temp.c_str(), "%p", &var);
		}
	};


	template<class charT, class traits> void __skipws(basic_istream<charT,traits>& is){
		const typename basic_istream<charT,traits>::int_type eof = traits::eof();
		typename basic_istream<charT,traits>::int_type c;
		//While the next character normally read doesn't equal eof
		//and that character is a space, advance to the next read position
		//Thus itterating through all whitespace until we get to the meaty stuff
		while (
			!traits::eq_int_type((c = is.rdbuf()->sgetc()),	eof)
			&& isspace(c)
                      )
		{
			is.rdbuf()->sbumpc();
		}
		if(traits::eq_int_type(c, eof)){
			is.setstate(ios_base::eofbit);
		}
	}
}

#pragma GCC visibility pop

#endif