// -*- C++ -*-
/***************************************************************************
 *
 * istream - Declarations for the Standard Library istreams
 *
 * $Id$
 *
 ***************************************************************************
 *
 * Copyright (c) 1994-2001 Rogue Wave Software, Inc.  All Rights Reserved.
 *
 * This computer software is owned by Rogue Wave Software, Inc. and is
 * protected by U.S. copyright laws and other laws and by international
 * treaties.  This computer software is furnished by Rogue Wave Software,
 * Inc. pursuant to a written license agreement and may be used, copied,
 * transmitted, and stored only in accordance with the terms of such
 * license and with the inclusion of the above copyright notice.  This
 * computer software or any other copies thereof may not be provided or
 * otherwise made available to any other person.
 *
 * U.S. Government Restricted Rights.  This computer software is provided
 * with Restricted Rights.  Use, duplication, or disclosure by the
 * Government is subject to restrictions as set forth in subparagraph (c)
 * (1) (ii) of The Rights in Technical Data and Computer Software clause
 * at DFARS 252.227-7013 or subparagraphs (c) (1) and (2) of the
 * Commercial Computer Software--Restricted Rights at 48 CFR 52.227-19,
 * as applicable.  Manufacturer is Rogue Wave Software, Inc., 5500
 * Flatiron Parkway, Boulder, Colorado 80301 USA.
 *
 **************************************************************************/

#ifndef _RWSTD_ISTREAM_INCLUDED
#define _RWSTD_ISTREAM_INCLUDED

#include <iosfwd>

#ifndef _RWSTD_NO_REDUNDANT_DEFINITIONS
#  include <ostream>
#endif   // _RWSTD_NO_REDUNDANT_DEFINITIONS

#include <rw/_iosbase.h>
#include <rw/_numeric.h>
#include <rw/_traits.h>

#include <rw/_defs.h>


_RWSTD_NAMESPACE_BEGIN (__rw)

template <class _CharT, class _Traits, class _NativeType>
basic_istream<_CharT, _Traits>&
__rw_extract (_STD::basic_istream<_CharT, _Traits>&, _NativeType&);

_RWSTD_NAMESPACE_END   // __rw


_RWSTD_NAMESPACE_BEGIN (std)

  
template<class _CharT, class _Traits /* = char_traits<char> */>
class basic_istream: virtual public basic_ios<_CharT, _Traits>
{
public:

    typedef _CharT                                    char_type;
    typedef _Traits                                   traits_type;
    typedef _TYPENAME traits_type::int_type           int_type;
    typedef _TYPENAME traits_type::pos_type           pos_type;
    typedef _TYPENAME traits_type::off_type           off_type;
      
    // 27.6.1.1.1, p1
    _EXPLICIT basic_istream (basic_streambuf<char_type, traits_type> *__sb)
        : _C_chcount (0) {
        this->init (__sb);
    }

    // called from sentry's ctor to prepare stream before input
    basic_istream& _C_ipfx (int __flags);

    // allow access to ios_base::_C_bufmutex()
    class sentry;
    friend class sentry;

    // 27.6.1.1.2
    class sentry: public _RW::__rw_guard
    {
        bool _C_ok;

        sentry (const sentry&);            //   not defined
        sentry& operator= (const sentry&); //   not defined

    public:

        // 27.6.1.1.2, p2 - assumes 0 != __strm.rdbuf ()
        _EXPLICIT sentry (basic_istream &__strm, bool __noskipws = false)
            :  _RW::__rw_guard (__strm._C_bufmutex ()) {
            int __flags = (__strm.flags () & ios_base::skipws && !__noskipws ?
                _C_skipws : 0) | _C_faileof;
                _C_ok = __strm._C_ipfx (__flags).good ();
        }

        // 27.6.1.1.2, p8
        operator bool () const {
            return _C_ok;
        }
    };

    // 27.6.1.2.3, p1
    basic_istream& operator>> (basic_istream& (*__pf)(basic_istream&)) {
        return (*__pf)(*this);
    }

    // 27.6.1.2.3, p2
    basic_istream& operator>>(basic_ios<char_type, traits_type>& (*__pf)
                              (basic_ios<char_type, traits_type>&)) {
        return (*__pf)(*this), *this;
    }

    // 27.6.1.2.3, p4
    basic_istream& operator>> (ios_base& (*__pf)(ios_base&)) {
        return (*__pf)(*this), *this;
    }


    // 27.6.1.2.2 - Arithmetic Extractors

#ifndef _RWSTD_NO_BOOL

    basic_istream& operator>> (bool &__val) {
        return _RW::__rw_extract (*this, __val);
    }

#endif   // _RWSTD_NO_BOOL

    basic_istream& operator>>(short &__val) {
        return _RW::__rw_extract (*this, __val);
    }

    basic_istream& operator>>(unsigned short &__val) {
        return _RW::__rw_extract (*this, __val);
    }

    basic_istream& operator>>(int &__val) {
        return _RW::__rw_extract (*this, __val);
    }

    basic_istream& operator>>(unsigned int &__val) {
        return _RW::__rw_extract (*this, __val);
    }

    basic_istream& operator>>(long &__val) {
        return _RW::__rw_extract (*this, __val);
    }

    basic_istream& operator>>(unsigned long &__val) {
        return _RW::__rw_extract (*this, __val);
    }

    basic_istream& operator>>(float &__val) {
        return _RW::__rw_extract (*this, __val);
    }

    basic_istream& operator>>(double &__val) {
        return _RW::__rw_extract (*this, __val);
    }

#ifndef _RWSTD_NO_LONG_DOUBLE
    basic_istream& operator>>(long double &__val) {
        return _RW::__rw_extract (*this, __val);
    }
#endif // _RWSTD_NO_LONG_DOUBLE

#ifdef _RWSTD_LONG_LONG

    basic_istream& operator>>(_RWSTD_LONG_LONG &__val) {
        return _RW::__rw_extract (*this, __val);
    }

    basic_istream& operator>>(unsigned _RWSTD_LONG_LONG &__val) {
        return _RW::__rw_extract (*this, __val);
    }

#endif   // _RWSTD_LONG_LONG

    basic_istream& operator>>(void* &__val) {
        return _RW::__rw_extract (*this, __val);
    }

    // extension
    basic_istream& operator>> (basic_streambuf<char_type, traits_type> &__sb) {
        // call extension
        return get (__sb, traits_type::eof ());
    }

    // 27.6.1.2.3, p13
    basic_istream& operator>>(basic_streambuf<char_type, traits_type> *__sb) {
        return  __sb ? *this >> *__sb
                     : (this->setstate (ios_base::failbit), *this);
    }

    // 27.6.1.3 - Unformatted input functions

    // 27.6.1.3, p3
    int_type get () {
        return sentry (*this, true) ?
              _C_unsafe_get (&_C_chcount, traits_type::eof (),
                             _C_faileof | _C_eatnull)
            : traits_type::eof ();
    }

    // 27.6.1.3, p5
    basic_istream& get (char_type& __ch) {
        return read (&__ch, 1, traits_type::eof (), _C_failnoi | _C_eatnull);
    }

    // 27.6.1.3, p7: extract at most n - 1 chars, delim not extracted
    //               always null-terminate, fail if no char extracted
    basic_istream& get (char_type *__s, streamsize __n, char_type __delim) {
        return read (__s, __n, traits_type::to_int_type (__delim),
                     _C_nullterm | _C_failnoi | _C_eatnull);
    }

    // 27.6.1.3, p9: extract at most n - 1 chars
    //               always null-terminate, fail if no char extracted
    basic_istream& get (char_type *__s, streamsize __n) {
        return get (__s, __n, this->widen ('\n'));
    }

    // extension - first arg is a pointer to disambiguate the overloads
    //             in case both int_type and char_type are the same type
    basic_istream& get (basic_streambuf<char_type, traits_type>*, int_type);

    // 27.6.1.3, p12: extract up to but not including delim or eof
    basic_istream& get (basic_streambuf<char_type, traits_type>& __sb,
                        char_type                                __delim) {
        // using extension
        return get (&__sb, traits_type::to_int_type (__delim));
    }

    // 27.6.1.3, p15
    basic_istream& get (basic_streambuf<char_type, traits_type>& __sb) {
        return get (__sb, this->widen ('\n'));
    }

    // 27.6.1.3, p16: extract at most n - 1, delim extracted but not stored
    //                fail if either 0 or n - 1 are extracted
    basic_istream& getline (char_type *__s, streamsize __n, char_type __delim) {
        // using extension
        return read (__s, __n, traits_type::to_int_type (__delim),
                       _C_nullterm | _C_eatdelim | _C_eatnull
                     | _C_failend | _C_failnoi);
    }

    // 27.6.1.3, p23
    basic_istream& getline (char_type *__s, streamsize __n) {
        return getline (__s, __n, this->widen ('\n'));
    }

    // 27.6.1.3, p24: extract at most n including delim
    basic_istream& ignore (streamsize __n = 1,
                           int_type __delim = traits_type::eof ()) {
        // using extension - passing null pointer to ignore input
        return read (0, __n, __delim, _C_eatdelim | _C_eatnull);
    }

    // extension
    basic_istream& read (char_type*, streamsize, int_type, int);

    // 27.6.1.3, p28: extract at most n, fail on eof
    basic_istream& read (char_type*, streamsize);

    // 27.6.1.3, p30: extract at most min (rdbuf()->in_avail(), n))
    streamsize readsome (char_type*, streamsize);

    // 27.6.1.3, p27
    int_type peek ();
      
    // 27.6.1.3, p37
    pos_type tellg ();

    // 27.6.1.3, p38
    basic_istream& seekg (pos_type);

    // 27.6.1.3, p40
    basic_istream& seekg (off_type, ios_base::seekdir);

    // 27.6.1.3, p36
    int sync ();

    // 27.6.1.3, p32
    basic_istream& putback (char_type);

    // 27.6.1.3, p34
    basic_istream& unget ();

    // 27.6.1.3, p2
    streamsize gcount () const {
        return _C_chcount;
    }

    // flags used by read() extension and _C_unsafe_get()
    enum {
        _C_nullterm = 0x01,   // null-terminate input
        _C_wsterm   = 0x02,   // terminate input on whitespace
        _C_skipws   = 0x04,   // skip leading whitespace
        _C_eatdelim = 0x08,   // extract delimiter
        _C_faileof  = 0x10,   // set ios_base::failbit on eof
        _C_failend  = 0x20,   // set ios_base::failbit on end of buffer
        _C_failnoi  = 0x40,   // set ios_base::failbit on no input
        _C_eatnull  = 0x80    // extract null char
    };

    // does not construct a sentry, does not affect gcount()
    // extracts character unless it is equal to __delim
    int_type _C_unsafe_get (streamsize* = 0,
                            int_type    = traits_type::eof (),
                            int         = 0);

protected:

    streamsize _C_chcount;   // number of chars extracted
};


// 27.6.1.4, p1
template<class _CharT, class _Traits>
inline basic_istream<_CharT, _Traits>&
ws (basic_istream<_CharT, _Traits> &__strm)
{
    return __strm._C_ipfx (basic_istream<_CharT, _Traits>::_C_skipws);
}


template<class _CharT, class _Traits>
inline basic_istream<_CharT, _Traits>&
basic_istream<_CharT, _Traits>::seekg (pos_type __pos)
{
    _RWSTD_ASSERT (0 != this->rdbuf ());

    if (!this->fail ()) {
        _RWSTD_MT_GUARD (this->_C_bufmutex ());

        // 27.6.1.3, p 38 requires that pubseekpos be called with
        // a single argument; the implemented behavior follows
        // the proposed resolution of lwg issue 136
        if (-1 == this->rdbuf ()->pubseekpos (__pos, ios_base::in))
            this->setstate (ios_base::failbit);   // lwg issue 129
    }

    return *this;
}


template<class _CharT, class _Traits>
inline basic_istream<_CharT, _Traits>&
basic_istream<_CharT, _Traits>::seekg (off_type __off, ios_base::seekdir __dir)
{
    _RWSTD_ASSERT (0 != this->rdbuf ());

    if (!this->fail ()) {
        _RWSTD_MT_GUARD (this->_C_bufmutex ());

        // 27.6.1.3, p 40 requires that pubseekoff be called with
        // two arguments; the implemented behavior follows
        // the proposed resolution of lwg issue 136
        if (-1 == this->rdbuf ()->pubseekoff (__off, __dir, ios_base::in))
            this->setstate (ios_base::failbit);   // lwg issue 129
    }

    return *this;
}


#ifndef _RWSTD_NO_SIGNED_CHAR_IN_STREAMS

// 27.6.1.2.3, p10
template <class _Traits>
inline basic_istream<char, _Traits>&
operator>> (basic_istream<char, _Traits>& __strm, 
            unsigned char&                __c)
{
    return __strm >> _RWSTD_REINTERPRET_CAST (char&, __c);
}

template <class _Traits>
inline basic_istream<char, _Traits>&
operator>> (basic_istream<char, _Traits>& __strm, 
            signed char&                  __c)
{
    return __strm >> _RWSTD_REINTERPRET_CAST (char&, __c);
}


// 27.6.1.2.3, p6
template <class _Traits>
inline basic_istream<char, _Traits>&
operator>> (basic_istream<char, _Traits>& __strm, 
            unsigned char*                __s)
{
    return __strm >> _RWSTD_REINTERPRET_CAST (char*, __s);
}


template <class _Traits>
inline basic_istream<char, _Traits>&
operator>> (basic_istream<char, _Traits>& __strm, 
            signed char* __s)
{
    return __strm >> _RWSTD_REINTERPRET_CAST (char*, __s);
}

#endif // _RWSTD_NO_SIGNED_CHAR_IN_STREAMS


template<class _CharT, class _Traits>
inline _TYPENAME basic_istream<_CharT, _Traits>::int_type
basic_istream<_CharT, _Traits>::peek ()
{
    _RWSTD_ASSERT (0 != this->rdbuf ());

    _C_chcount = 0;

    return sentry (*this, true) ? this->rdbuf ()->sgetc ()
                                : traits_type::eof ();
}


// 27.6.1.2.3, p10
template<class _CharT, class _Traits>
inline basic_istream<_CharT, _Traits>&
operator>> (basic_istream<_CharT, _Traits> &__strm, _CharT &__c)
{
    // read the first non-space char, set failbit if none read
    return __strm.read (&__c, 1, _Traits::eof (),
                        __strm._C_skipws | __strm._C_failnoi | __strm._C_eatnull);
}


// 27.6.1.2.3, p6
template<class _CharT, class _Traits>
inline basic_istream<_CharT, _Traits>&
operator>> (basic_istream<_CharT, _Traits> &__strm, _CharT *__s)
{
    _RWSTD_ASSERT (0 != __s);

    // store at most this many chars including terminating null
    const streamsize __maxlen = __strm.width () ? __strm.width () :
                                numeric_limits<streamsize>::max () - 1;

    // read at most __maxlen non-space chars up to the first whitespace
    __strm.read (__s, __maxlen, _Traits::to_int_type (__strm.widen ('\n')),
                   __strm._C_nullterm | __strm._C_wsterm
                 | __strm._C_skipws   | __strm._C_failnoi);

    __strm.width (0);

    return __strm;
}


template<class _CharT, class _Traits, class _Allocator>
basic_istream<_CharT, _Traits>&
operator>> (basic_istream<_CharT, _Traits>&,
            basic_string<_CharT, _Traits, _Allocator>&);


template<class _CharT, class _Traits, class _Allocator>
basic_istream<_CharT, _Traits>&
getline (basic_istream<_CharT, _Traits>&,
         basic_string<_CharT, _Traits, _Allocator>&,
         _CharT);


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


// 27.6.1.5
template<class _CharT, class _Traits /* = char_traits<_CharT> */>
class basic_iostream
    : public basic_istream<_CharT, _Traits>,
      public basic_ostream<_CharT, _Traits> 
{
public:

    // prevent ambiguity between types defined in the bases
    typedef _CharT                          char_type;
    typedef _Traits                         traits_type;
    typedef _TYPENAME traits_type::int_type int_type;
    typedef _TYPENAME traits_type::pos_type pos_type;
    typedef _TYPENAME traits_type::off_type off_type;

    _EXPLICIT basic_iostream (basic_streambuf<_CharT, _Traits> *__sb)
        : basic_istream<_CharT, _Traits> (__sb), 
          basic_ostream<_CharT, _Traits> (__sb)
        { /* 27.6.1.5.1, p1 */ }
};


_RWSTD_INSTANTIATE_2 (class _RWSTD_EXPORT
                      basic_istream<char, char_traits<char> >);
_RWSTD_INSTANTIATE_1 (_RWSTD_EXPORT istream& operator>> (istream&, string&));
_RWSTD_INSTANTIATE_1 (_RWSTD_EXPORT istream&
                      getline (istream&, string&, char));

#ifndef _RWSTD_NO_WCHAR_T
_RWSTD_INSTANTIATE_2 (class _RWSTD_EXPORT
                      basic_istream<wchar_t, char_traits<wchar_t> >);
_RWSTD_INSTANTIATE_1 (_RWSTD_EXPORT wistream&
                      operator>> (wistream&, wstring&));
_RWSTD_INSTANTIATE_1 (_RWSTD_EXPORT wistream&
                      getline (wistream&, wstring&, wchar_t));
#endif   // _RWSTD_NO_WCHAR_T

_RWSTD_NAMESPACE_END   // std


#if _RWSTD_DEFINE_TEMPLATE (BASIC_ISTREAM)
#  include <istream.cc>
#endif


#endif   // _RWSTD_ISTREAM_INCLUDED

