istream.tcc

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    basic_istream<_CharT, _Traits>&
    basic_istream<_CharT, _Traits>::
    putback(char_type __c)
    {
      const int_type __eof = traits_type::eof();
      _M_gcount = 0;
      sentry __cerb(*this, true);
      if (__cerb) 
	{
	  try {
	    __streambuf_type* __sb = this->rdbuf();
	    if (!__sb || __eof == __sb->sputbackc(__c)) 
	      this->setstate(ios_base::badbit);		    
	  }
	  catch(exception& __fail){
	    // 27.6.1.3 paragraph 1
	    // Turn this on without causing an ios::failure to be thrown.
	    this->setstate(ios_base::badbit);
	    if ((this->exceptions() & ios_base::badbit) != 0)
	      throw;
	  }
	}
      else
	this->setstate(ios_base::failbit);
      return *this;
    }
  
  template<typename _CharT, typename _Traits>
    basic_istream<_CharT, _Traits>&
    basic_istream<_CharT, _Traits>::
    unget()
    {
      const int_type __eof = traits_type::eof();
      _M_gcount = 0;
      sentry __cerb(*this, true);
      if (__cerb) 
	{
	  try {
	    __streambuf_type* __sb = this->rdbuf();
	    if (!__sb || __eof == __sb->sungetc())
	      this->setstate(ios_base::badbit);		    
	  }
	  catch(exception& __fail){
	    // 27.6.1.3 paragraph 1
	    // Turn this on without causing an ios::failure to be thrown.
	    this->setstate(ios_base::badbit);
	    if ((this->exceptions() & ios_base::badbit) != 0)
	      throw;
	  }
	}
      else
	this->setstate(ios_base::failbit);
      return *this;
    }
  
  template<typename _CharT, typename _Traits>
    int
    basic_istream<_CharT, _Traits>::sync()
    {
      int __retval = traits_type::eof();
      _M_gcount = 0;
      sentry __cerb(*this, true);
      if (__cerb) 
	{
	  try {
	    __streambuf_type* __sb = this->rdbuf();
	    if (!__sb || __retval == __sb->pubsync())
	      this->setstate(ios_base::badbit);		    
	    else 
	      __retval = 0;
	  }
	  catch(exception& __fail){
	    // 27.6.1.3 paragraph 1
	    // Turn this on without causing an ios::failure to be thrown.
	    this->setstate(ios_base::badbit);
	    if ((this->exceptions() & ios_base::badbit) != 0)
	      throw;
	  }
	}
      return __retval;
    }
  
  template<typename _CharT, typename _Traits>
    typename basic_istream<_CharT, _Traits>::pos_type
    basic_istream<_CharT, _Traits>::tellg()
    {
      pos_type __retval = pos_type(-1);
      bool __testok = this->fail() != true;
      _M_gcount = 0;
      sentry __cerb(*this, true);
      if (__cerb) 
	{
	  try {
	    if (__testok)
	      __retval = this->rdbuf()->pubseekoff(0, ios_base::cur, 
						   ios_base::in);
	    _M_gcount = __retval;
	  }
	  catch(exception& __fail){
	    // 27.6.1.3 paragraph 1
	    // Turn this on without causing an ios::failure to be thrown.
	    this->setstate(ios_base::badbit);
	    if ((this->exceptions() & ios_base::badbit) != 0)
	      throw;
	  }
	}
      return __retval;
    }


  template<typename _CharT, typename _Traits>
    basic_istream<_CharT, _Traits>&
    basic_istream<_CharT, _Traits>::seekg(pos_type __pos)
    {
      bool __testok = this->fail() != true;
      _M_gcount = 0;
      sentry __cerb(*this, true);
      if (__cerb) 
	{
	  try {
	    if (__testok)
	      _M_gcount = this->rdbuf()->pubseekpos(__pos);
	  }
	  catch(exception& __fail){
	    // 27.6.1.3 paragraph 1
	    // Turn this on without causing an ios::failure to be thrown.
	    this->setstate(ios_base::badbit);
	    if ((this->exceptions() & ios_base::badbit) != 0)
	      throw;
	  }
	}
      return *this;
    }

  template<typename _CharT, typename _Traits>
    basic_istream<_CharT, _Traits>&
    basic_istream<_CharT, _Traits>::seekg(off_type __off, 
					  ios_base::seekdir __dir)
    {
      bool __testok = this->fail() != true;
      _M_gcount = 0;
      sentry __cerb(*this, true);
      if (__cerb) 
	{
	  try {
	    if (__testok)
	      _M_gcount = this->rdbuf()->pubseekoff(__off, __dir);
	  }
	  catch(exception& __fail){
	    // 27.6.1.3 paragraph 1
	    // Turn this on without causing an ios::failure to be thrown.
	    this->setstate(ios_base::badbit);
	    if ((this->exceptions() & ios_base::badbit) != 0)
	      throw;
	  }
	}
      return *this;
    }

  // 27.6.1.2.3 Character extraction templates
  template<typename _CharT, typename _Traits>
    basic_istream<_CharT, _Traits>&
    operator>>(basic_istream<_CharT, _Traits>& __in, _CharT& __c)
    {
      typedef basic_istream<char, _Traits> __istream_type;
      __istream_type::sentry __cerb(__in, false);
      if (__cerb)
	{
	  try {
	    __in.get(__c);
	  }
	  catch(exception& __fail){
	    // 27.6.1.2.1 Common requirements.
	    // Turn this on without causing an ios::failure to be thrown.
	    __in.setstate(ios_base::badbit);
	    if ((__in.exceptions() & ios_base::badbit) != 0)
	      throw;
	  }
	}
      else
	__in.setstate(ios_base::failbit);
      return __in;
    }

  template<typename _CharT, typename _Traits>
    basic_istream<_CharT, _Traits>&
    operator>>(basic_istream<_CharT, _Traits>& __in, _CharT* __s)
    {
      typedef basic_istream<_CharT, _Traits> 		__istream_type;
      typedef typename __istream_type::__streambuf_type __streambuf_type;
      typedef typename _Traits::int_type 		int_type;
      typedef _CharT                     		char_type;
      typedef ctype<_CharT>           			__ctype_type;
      int_type __extracted = 0;

      __istream_type::sentry __cerb(__in, false);
      if (__cerb)
	{
	  try {
	    // Figure out how many characters to extract.
	    streamsize __num = __in.width();
	    if (__num <= 0)
	      __num = basic_string<_CharT, _Traits>::npos;

	    __streambuf_type* __sb = __in.rdbuf();
	    const __ctype_type* __ctype = __in._M_get_fctype_ios();
	    int_type __c = __sb->sbumpc();
	    const int_type __eof = _Traits::eof();
	    bool __testsp = __ctype->is(ctype_base::space, __c);
	    bool __testeof =  __c == __eof;
	    
	    while (__extracted < __num - 1 && !__testeof && !__testsp)
	      {
		*__s++ = __c;
		++__extracted;
		__c = __sb->sbumpc();
		__testeof = __c == __eof;
		__testsp = __ctype->is(ctype_base::space, __c);
	      }
	    
	    if (!__testeof)
	      __sb->sputbackc(__c);
	    else
	      __in.setstate(ios_base::eofbit);

#ifdef _GLIBCPP_RESOLVE_LIB_DEFECTS
//68.  Extractors for char* should store null at end
	    *__s = char_type();
#endif
	    __in.width(0);
	  }
	  catch(exception& __fail){
	    // 27.6.1.2.1 Common requirements.
	    // Turn this on without causing an ios::failure to be thrown.
	    __in.setstate(ios_base::badbit);
	    if ((__in.exceptions() & ios_base::badbit) != 0)
	      throw;
	  }
	}
      if (!__extracted)
	__in.setstate(ios_base::failbit);
      return __in;
    }

  // 27.6.1.4 Standard basic_istream manipulators
  template<typename _CharT, typename _Traits>
    basic_istream<_CharT,_Traits>& 
    ws(basic_istream<_CharT,_Traits>& __in)
    {
      typedef basic_istream<_CharT, _Traits> 		__istream_type;
      typedef typename __istream_type::__streambuf_type __streambuf_type;
      typedef typename __istream_type::__ctype_type 	__ctype_type;
      typedef typename __istream_type::int_type 	__int_type;
      typedef typename __istream_type::char_type 	__char_type;

      __streambuf_type* __sb = __in.rdbuf();
      const __ctype_type* __ctype = __in._M_get_fctype_ios();
      const __int_type __eof = _Traits::eof();	      
      __int_type __c;
      bool __testeof;
      bool __testsp;

      do 
	{
	  __c = __sb->sbumpc();
	  __testeof = __c == __eof;
	  __testsp = __ctype->is(ctype_base::space, __c);
	}
      while (!__testeof && __testsp);

      if (!__testeof && !__testsp)
	__sb->sputbackc(__c);
      else
	__in.setstate(ios_base::eofbit);

      return __in;
    }

  // 21.3.7.8 basic_string::getline and operators
  template<typename _CharT, typename _Traits, typename _Alloc>
    basic_istream<_CharT, _Traits>&
    operator>>(basic_istream<_CharT, _Traits>& __in,
	       basic_string<_CharT, _Traits, _Alloc>& __str)
    {
      typedef basic_istream<_CharT, _Traits> 		__istream_type;
      typedef typename __istream_type::int_type 	__int_type;
      typedef typename __istream_type::__streambuf_type __streambuf_type;
      typedef typename __istream_type::__ctype_type 	__ctype_type;
      typedef basic_string<_CharT, _Traits, _Alloc> 	__string_type;
      typedef typename __string_type::size_type		__size_type;

      __istream_type::sentry __cerb(__in, false);
      if (__cerb) 
	{
	  __str.erase();
	  streamsize __w = __in.width();
	  __size_type __n;
	  __n = __w > 0 ? static_cast<__size_type>(__w) : __str.max_size();

	  __int_type __extracted = 0;
	  __streambuf_type* __sb = __in.rdbuf();
	  const __ctype_type* __ctype = __in._M_get_fctype_ios();
	  __int_type __c = __sb->sbumpc();
	  const __int_type __eof = _Traits::eof();
	  bool __testsp = __ctype->is(ctype_base::space, __c);
	  bool __testeof =  __c == __eof;

	  while ( __extracted <= __n && !__testeof && !__testsp)
	    {
	      __str += _Traits::to_char_type(__c);
	      ++__extracted;
	      __c = __sb->sbumpc();
	      __testeof = __c == __eof;
	      __testsp = __ctype->is(ctype_base::space, __c);
	    }
	  if (!__testeof)
	    __sb->sputbackc(__c);
	  else
	    __in.setstate(ios_base::eofbit);

	  __in.width(0);
	}
      return __in;
    }

  template<typename _CharT, typename _Traits, typename _Alloc>
    basic_istream<_CharT, _Traits>&
    getline(basic_istream<_CharT, _Traits>& __in,
	    basic_string<_CharT, _Traits, _Alloc>& __str, _CharT __delim)
    {
      typedef basic_istream<_CharT, _Traits> 		__istream_type;
      typedef typename __istream_type::int_type 	__int_type;
      typedef typename __istream_type::__streambuf_type __streambuf_type;
      typedef typename __istream_type::__ctype_type 	__ctype_type;
      typedef basic_string<_CharT, _Traits, _Alloc> 	__string_type;
      typedef typename __string_type::size_type		__size_type;

      __size_type __extracted = 0;
      bool __testdelim = false;
      __istream_type::sentry __cerb(__in, true);
      if (__cerb) 
	{
	  __str.erase();
	  __size_type __n = __str.max_size();

	  __int_type __idelim = _Traits::to_int_type(__delim);
	  __streambuf_type* __sb = __in.rdbuf();
	  __int_type __c = __sb->sbumpc();
	  const __int_type __eof = _Traits::eof();
	  __testdelim = __idelim == __c;
	  bool __testeof =  __c == __eof;

	  while (__extracted <= __n && !__testeof && !__testdelim)
	    {
	      __str += _Traits::to_char_type(__c);
	      ++__extracted;
	      __c = __sb->sbumpc();
	      __testeof = __c == __eof;
	      __testdelim = __c == __idelim;
	    }
	  
	  if (__testeof)
	    __in.setstate(ios_base::eofbit);

	}
      if (!__extracted && !__testdelim)
	__in.setstate(ios_base::failbit);
      return __in;
    }

  template<class _CharT, class _Traits, class _Alloc>
    inline basic_istream<_CharT,_Traits>&
    getline(basic_istream<_CharT, _Traits>& __in, 
	    basic_string<_CharT,_Traits,_Alloc>& __str)
    { return getline(__in, __str, __in.widen('\n')); }

} // namespace std

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// mode:C++
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