istream.tcc

gcc-you can use this code to learn something about gcc, and inquire further into linux,

	    {
	      ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
	      if (_M_check_facet(_M_fnumget))
		_M_fnumget->get(*this, 0, *this, __err, __n);
	      this->setstate(__err);
	    }
	  catch(...)
	    {
	      // 27.6.1.2.1 Common requirements.
	      // Turn this on without causing an ios::failure to be thrown.
	      this->_M_setstate(ios_base::badbit);
	      if ((this->exceptions() & ios_base::badbit) != 0)
		__throw_exception_again;
	    }
	}
      return *this;
    }

  template<typename _CharT, typename _Traits>
    basic_istream<_CharT, _Traits>& 
    basic_istream<_CharT, _Traits>::
    operator>>(long double& __n)
    {
      sentry __cerb(*this, false);
      if (__cerb) 
	{
	  try 
	    {
	      ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
	      if (_M_check_facet(_M_fnumget))
		_M_fnumget->get(*this, 0, *this, __err, __n);
	      this->setstate(__err);
	    }
	  catch(...)
	    {
	      // 27.6.1.2.1 Common requirements.
	      // Turn this on without causing an ios::failure to be thrown.
	      this->_M_setstate(ios_base::badbit);
	      if ((this->exceptions() & ios_base::badbit) != 0)
		__throw_exception_again;
	    }
	}
      return *this;
    }

  template<typename _CharT, typename _Traits>
    basic_istream<_CharT, _Traits>& 
    basic_istream<_CharT, _Traits>::
    operator>>(void*& __n)
    {
      sentry __cerb(*this, false);
      if (__cerb) 
	{
	  try 
	    {
	      ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
	      if (_M_check_facet(_M_fnumget))
		_M_fnumget->get(*this, 0, *this, __err, __n);
	      this->setstate(__err);
	    }
	  catch(...)
	    {
	      // 27.6.1.2.1 Common requirements.
	      // Turn this on without causing an ios::failure to be thrown.
	      this->_M_setstate(ios_base::badbit);
	      if ((this->exceptions() & ios_base::badbit) != 0)
		__throw_exception_again;
	    }
	}
      return *this;
    }

  template<typename _CharT, typename _Traits>
    basic_istream<_CharT, _Traits>& 
    basic_istream<_CharT, _Traits>::
    operator>>(__streambuf_type* __sbout)
    {
       sentry __cerb(*this, false);
       if (__cerb)
	 {
	   try
	     {
	       streamsize __xtrct = 0;
	       if (__sbout)
		 {
		   __streambuf_type* __sbin = this->rdbuf();
		   __xtrct = __copy_streambufs(*this, __sbin, __sbout);
		 }
	       if (!__sbout || !__xtrct)
		 this->setstate(ios_base::failbit);
	     }
	   catch(...)
	     {
	       // 27.6.2.5.1 Common requirements.
	       // Turn this on without causing an ios::failure to be thrown.
	       this->_M_setstate(ios_base::badbit);
	       if ((this->exceptions() & ios_base::badbit) != 0)
		 __throw_exception_again;
	     }
	 }
       return *this;
    }

  template<typename _CharT, typename _Traits>
    typename basic_istream<_CharT, _Traits>::int_type
    basic_istream<_CharT, _Traits>::
    get(void)
    {
      const int_type __eof = traits_type::eof();
      int_type __c = __eof;
      _M_gcount = 0;
      sentry __cerb(*this, true);
      if (__cerb) 
	{
	  try 
	    {
	      __c = this->rdbuf()->sbumpc();
	      // 27.6.1.1 paragraph 3
	      if (!traits_type::eq_int_type(__c, __eof))
		_M_gcount = 1;
	      else
		this->setstate(ios_base::eofbit | ios_base::failbit);
	    }
	  catch(...)
	    {
	      // 27.6.1.3 paragraph 1
	      // Turn this on without causing an ios::failure to be thrown.
	      this->_M_setstate(ios_base::badbit);
	      if ((this->exceptions() & ios_base::badbit) != 0)
		__throw_exception_again;
	    }
	}
      return __c;
    }

  template<typename _CharT, typename _Traits>
    basic_istream<_CharT, _Traits>&
    basic_istream<_CharT, _Traits>::
    get(char_type& __c)
    {
      _M_gcount = 0;
      sentry __cerb(*this, true);
      if (__cerb) 
	{
 	  try 
	    {
	      const int_type __eof = traits_type::eof();
	      int_type __bufval = this->rdbuf()->sbumpc();
	      // 27.6.1.1 paragraph 3
	      if (!traits_type::eq_int_type(__bufval, __eof))
		{
		  _M_gcount = 1;
		  __c = traits_type::to_char_type(__bufval);
		}
	      else
		this->setstate(ios_base::eofbit | ios_base::failbit);
	    }
	  catch(...)
	    {
	      // 27.6.1.3 paragraph 1
	      // Turn this on without causing an ios::failure to be thrown.
	      this->_M_setstate(ios_base::badbit);
	      if ((this->exceptions() & ios_base::badbit) != 0)
		__throw_exception_again;
	    }
	}
      return *this;
    }

  template<typename _CharT, typename _Traits>
    basic_istream<_CharT, _Traits>&
    basic_istream<_CharT, _Traits>::
    get(char_type* __s, streamsize __n, char_type __delim)
    {
      _M_gcount = 0;
      sentry __cerb(*this, true);
      if (__cerb) 
	{
	  try 
	    {
	      const int_type __idelim = traits_type::to_int_type(__delim);
	      const int_type __eof = traits_type::eof();
	      __streambuf_type* __sb = this->rdbuf();
	      int_type __c = __sb->sgetc();	
	      
	      while (_M_gcount + 1 < __n 
		     && !traits_type::eq_int_type(__c, __eof)
		     && !traits_type::eq_int_type(__c, __idelim))
		{
		  *__s++ = traits_type::to_char_type(__c);
		  __c = __sb->snextc();
		  ++_M_gcount;
		}
	      if (traits_type::eq_int_type(__c, __eof))
		this->setstate(ios_base::eofbit);
	    }
	  catch(...)
	    {
	      // 27.6.1.3 paragraph 1
	      // Turn this on without causing an ios::failure to be thrown.
	      this->_M_setstate(ios_base::badbit);
	      if ((this->exceptions() & ios_base::badbit) != 0)
		__throw_exception_again;
	    }
	}
      *__s = char_type();
      if (!_M_gcount)
	this->setstate(ios_base::failbit);
      return *this;
    }

  template<typename _CharT, typename _Traits>
    basic_istream<_CharT, _Traits>&
    basic_istream<_CharT, _Traits>::
    get(__streambuf_type& __sb, char_type __delim)
    {
      _M_gcount = 0;
      sentry __cerb(*this, true);
      if (__cerb) 
	{
	  try 
	    {
	      const int_type __idelim = traits_type::to_int_type(__delim);
	      const int_type __eof = traits_type::eof();	      
	      __streambuf_type* __this_sb = this->rdbuf();
	      int_type __c = __this_sb->sgetc();
	      char_type __c2 = traits_type::to_char_type(__c);
	      
	      while (!traits_type::eq_int_type(__c, __eof) 
		     && !traits_type::eq_int_type(__c, __idelim) 
		     && !traits_type::eq_int_type(__sb.sputc(__c2), __eof))
		{
		  ++_M_gcount;
		  __c = __this_sb->snextc();
		  __c2 = traits_type::to_char_type(__c);
		}
	      if (traits_type::eq_int_type(__c, __eof))
		this->setstate(ios_base::eofbit);
	    }
	  catch(...)
	    {
	      // 27.6.1.3 paragraph 1
	      // Turn this on without causing an ios::failure to be thrown.
	      this->_M_setstate(ios_base::badbit);
	      if ((this->exceptions() & ios_base::badbit) != 0)
		__throw_exception_again;
	    }
	}
      if (!_M_gcount)
	this->setstate(ios_base::failbit);
      return *this;
    }

  template<typename _CharT, typename _Traits>
    basic_istream<_CharT, _Traits>&
    basic_istream<_CharT, _Traits>::
    getline(char_type* __s, streamsize __n, char_type __delim)
    {
      _M_gcount = 0;
      sentry __cerb(*this, true);
      if (__cerb) 
	{
          try 
	    {
	      const int_type __idelim = traits_type::to_int_type(__delim);
	      const int_type __eof = traits_type::eof();
	      __streambuf_type* __sb = this->rdbuf();
	      int_type __c = __sb->sgetc();
	    
	      while (_M_gcount + 1 < __n 
		     && !traits_type::eq_int_type(__c, __eof)
		     && !traits_type::eq_int_type(__c, __idelim))
		{
		  *__s++ = traits_type::to_char_type(__c);
		  __c = __sb->snextc();
		  ++_M_gcount;
		}
	      if (traits_type::eq_int_type(__c, __eof))
		this->setstate(ios_base::eofbit);
	      else
		{
		  if (traits_type::eq_int_type(__c, __idelim))
		    {
		      __sb->sbumpc();
		      ++_M_gcount;
		    }
		  else
		    this->setstate(ios_base::failbit);
		}
	    }
	  catch(...)
	    {
	      // 27.6.1.3 paragraph 1
	      // Turn this on without causing an ios::failure to be thrown.
	      this->_M_setstate(ios_base::badbit);
	      if ((this->exceptions() & ios_base::badbit) != 0)
		__throw_exception_again;
	    }
	}
      *__s = char_type();
      if (!_M_gcount)
	this->setstate(ios_base::failbit);
      return *this;
    }
  
  template<typename _CharT, typename _Traits>
    basic_istream<_CharT, _Traits>&
    basic_istream<_CharT, _Traits>::
    ignore(streamsize __n, int_type __delim)
    {
      _M_gcount = 0;
      sentry __cerb(*this, true);
      if (__cerb && __n > 0) 
	{
	  try 
	    {
	      const int_type __eof = traits_type::eof();
	      __streambuf_type* __sb = this->rdbuf();
	      int_type __c;
	      
	      __n = min(__n, numeric_limits<streamsize>::max());
	      while (_M_gcount < __n  
		     && !traits_type::eq_int_type(__c = __sb->sbumpc(), __eof))
		{
		  ++_M_gcount;
		  if (traits_type::eq_int_type(__c, __delim))
		    break;
		}
	      if (traits_type::eq_int_type(__c, __eof))
		this->setstate(ios_base::eofbit);
	    }
	  catch(...)
	    {
	      // 27.6.1.3 paragraph 1
	      // Turn this on without causing an ios::failure to be thrown.
	      this->_M_setstate(ios_base::badbit);
	      if ((this->exceptions() & ios_base::badbit) != 0)
		__throw_exception_again;
	    }
	}
      return *this;
    }
  
  template<typename _CharT, typename _Traits>
    typename basic_istream<_CharT, _Traits>::int_type
    basic_istream<_CharT, _Traits>::
    peek(void)
    {
      int_type __c = traits_type::eof();
      _M_gcount = 0;
      sentry __cerb(*this, true);
      if (__cerb)
	{
	  try 
	    { __c = this->rdbuf()->sgetc(); }
	  catch(...)
	    {
	      // 27.6.1.3 paragraph 1
	      // Turn this on without causing an ios::failure to be thrown.
	      this->_M_setstate(ios_base::badbit);
	      if ((this->exceptions() & ios_base::badbit) != 0)
		__throw_exception_again;
	    }
	} 
      return __c;
    }

  template<typename _CharT, typename _Traits>
    basic_istream<_CharT, _Traits>&
    basic_istream<_CharT, _Traits>::
    read(char_type* __s, streamsize __n)
    {
      _M_gcount = 0;
      sentry __cerb(*this, true);
      if (__cerb) 
	{
	  try 
	    {
	      _M_gcount = this->rdbuf()->sgetn(__s, __n);
	      if (_M_gcount != __n)
		this->setstate(ios_base::eofbit | ios_base::failbit);
	    }	    
	  catch(...)
	    {
	      // 27.6.1.3 paragraph 1
	      // Turn this on without causing an ios::failure to be thrown.
	      this->_M_setstate(ios_base::badbit);
	      if ((this->exceptions() & ios_base::badbit) != 0)
		__throw_exception_again;
	    }
	}
      else
	this->setstate(ios_base::failbit);
      return *this;
    }
  
  template<typename _CharT, typename _Traits>
    streamsize 
    basic_istream<_CharT, _Traits>::
    readsome(char_type* __s, streamsize __n)
    {
      _M_gcount = 0;
      sentry __cerb(*this, true);
      if (__cerb) 
	{
	  try