/*

 * Copyright (c) 1999

 * Silicon Graphics Computer Systems, Inc.

 *

 * Copyright (c) 1999

 * Boris Fomitchev

 *

 * This material is provided "as is", with absolutely no warranty expressed

 * or implied. Any use is at your own risk.

 *

 * Permission to use or copy this software for any purpose is hereby granted

 * without fee, provided the above notices are retained on all copies.

 * Permission to modify the code and to distribute modified code is granted,

 * provided the above notices are retained, and a notice that the code was

 * modified is included with the above copyright notice.

 *

 */

// Implementation of the classes in header <strstream>.

// WARNING: The classes defined in <strstream> are DEPRECATED.  This

// header is defined in section D.7.1 of the C++ standard, and it

// MAY BE REMOVED in a future standard revision.  You should use the

// header <sstream> instead.

#include "stlport_prefix.h"

#include <strstream>

#include <algorithm>

#include <limits>

_STLP_BEGIN_NAMESPACE

// strstreambuf constructor, destructor.

strstreambuf::strstreambuf(streamsize initial_capacity)

   : _M_alloc_fun(0), _M_free_fun(0),

     _M_dynamic(true), _M_frozen(false), _M_constant(false) {

  size_t n = (sizeof(streamsize) > sizeof(size_t)) ? __STATIC_CAST(size_t, (min)(__STATIC_CAST(streamsize, (numeric_limits<size_t>::max)()),

                                                                                 (max)(initial_capacity, streamsize(16))))

                                                   : __STATIC_CAST(size_t, (max)(initial_capacity, streamsize(16)));

  char* buf = _M_alloc(n);

  if (buf) {

    setp(buf, buf + n);

    setg(buf, buf, buf);

  }

}

strstreambuf::strstreambuf(__alloc_fn alloc_f, __free_fn free_f)

  : _M_alloc_fun(alloc_f), _M_free_fun(free_f),

    _M_dynamic(true), _M_frozen(false), _M_constant(false) {

  size_t n = 16;

  char* buf = _M_alloc(n);

  if (buf) {

    setp(buf, buf + n);

    setg(buf, buf, buf);

  }

}

strstreambuf::strstreambuf(char* get, streamsize n, char* put)

  : _M_alloc_fun(0), _M_free_fun(0),

    _M_dynamic(false), _M_frozen(false), _M_constant(false) {

  _M_setup(get, put, n);

}

strstreambuf::strstreambuf(signed char* get, streamsize n, signed char* put)

  : _M_alloc_fun(0), _M_free_fun(0),

    _M_dynamic(false), _M_frozen(false), _M_constant(false) {

  _M_setup(__REINTERPRET_CAST(char*,get), __REINTERPRET_CAST(char*,put), n);

}

strstreambuf::strstreambuf(unsigned char* get, streamsize n,

                           unsigned char* put)

  : _M_alloc_fun(0), _M_free_fun(0),

    _M_dynamic(false), _M_frozen(false), _M_constant(false) {

  _M_setup(__REINTERPRET_CAST(char*,get), __REINTERPRET_CAST(char*,put), n);

}

strstreambuf::strstreambuf(const char* get, streamsize n)

  : _M_alloc_fun(0), _M_free_fun(0),

    _M_dynamic(false), _M_frozen(false), _M_constant(true) {

  _M_setup(__CONST_CAST(char*,get), 0, n);

}

strstreambuf::strstreambuf(const signed char* get, streamsize n)

  : _M_alloc_fun(0), _M_free_fun(0),

    _M_dynamic(false), _M_frozen(false), _M_constant(true) {

  _M_setup(__REINTERPRET_CAST(char*, __CONST_CAST(signed char*,get)), 0, n);

}

strstreambuf::strstreambuf(const unsigned char* get, streamsize n)

  : _M_alloc_fun(0), _M_free_fun(0),

    _M_dynamic(false), _M_frozen(false), _M_constant(true) {

  _M_setup(__REINTERPRET_CAST(char*, __CONST_CAST(unsigned char*,get)), 0, n);

}

strstreambuf::~strstreambuf() {

  if (_M_dynamic && !_M_frozen)

    _M_free(eback());

}

void strstreambuf::freeze(bool frozenflag) {

  if (_M_dynamic)

    _M_frozen = frozenflag;

}

char* strstreambuf::str() {

  freeze(true);

  return eback();

}

int strstreambuf::pcount() const {

  return int(pptr() ? pptr() - pbase() : 0);

}

strstreambuf::int_type strstreambuf::overflow(int_type c) {

  if (c == traits_type::eof())

    return traits_type::not_eof(c);

  // Try to expand the buffer.

  if (pptr() == epptr() && _M_dynamic && !_M_frozen && !_M_constant) {

    ptrdiff_t old_size = epptr() - pbase();

    ptrdiff_t new_size = (max)(2 * old_size, ptrdiff_t(1));

    char* buf = _M_alloc(new_size);

    if (buf) {

      memcpy(buf, pbase(), old_size);

      char* old_buffer = pbase();

      bool reposition_get = false;

      ptrdiff_t old_get_offset;

      if (gptr() != 0) {

        reposition_get = true;

        old_get_offset = gptr() - eback();

      }

      setp(buf, buf + new_size);

      pbump((int)old_size);

      if (reposition_get)

        setg(buf, buf + old_get_offset, buf + (max)(old_get_offset, old_size));

      _M_free(old_buffer);

    }

  }

  if (pptr() != epptr()) {

    *pptr() = traits_type::to_char_type(c);

    pbump(1);

    return c;

  }

  else

    return traits_type::eof();

}

strstreambuf::int_type strstreambuf::pbackfail(int_type c) {

  if (gptr() != eback()) {

    if (c == traits_type::eof()) {

      gbump(-1);

      return traits_type::not_eof(c);

    }

    else if (c == gptr()[-1]) {

      gbump(-1);

      return c;

    }

    else if (!_M_constant) {

      gbump(-1);

      *gptr() = traits_type::to_char_type(c);

      return c;

    }

  }

  return traits_type::eof();

}

strstreambuf::int_type strstreambuf::underflow() {

  if (gptr() == egptr() && pptr() && pptr() > egptr())

    setg(eback(), gptr(), pptr());

  if (gptr() != egptr())

    return (unsigned char) *gptr();

  else

    return _Traits::eof();

}

basic_streambuf<char, char_traits<char> >*

strstreambuf::setbuf(char*, streamsize) {

  return this;

}

strstreambuf::pos_type

strstreambuf::seekoff(off_type off,

                      ios_base::seekdir dir, ios_base::openmode mode) {

  bool do_get = false;

  bool do_put = false;

  if ((mode & (ios_base::in | ios_base::out)) ==

          (ios_base::in | ios_base::out) &&

      (dir == ios_base::beg || dir == ios_base::end))

    do_get = do_put = true;

  else if (mode & ios_base::in)

    do_get = true;

  else if (mode & ios_base::out)

    do_put = true;

  // !gptr() is here because, according to D.7.1 paragraph 4, the seekable

  // area is undefined if there is no get area.

  if ((!do_get && !do_put) || (do_put && !pptr()) || !gptr())

    return pos_type(off_type(-1));

  char* seeklow  = eback();

  char* seekhigh = epptr() ? epptr() : egptr();

  off_type newoff;

  switch(dir) {

  case ios_base::beg:

    newoff = 0;

    break;

  case ios_base::end:

    newoff = seekhigh - seeklow;

    break;

  case ios_base::cur:

    newoff = do_put ? pptr() - seeklow : gptr() - seeklow;

    break;

  default:

    return pos_type(off_type(-1));

  }

  off += newoff;

  if (off < 0 || off > seekhigh - seeklow)

    return pos_type(off_type(-1));

  if (do_put) {

    if (seeklow + __STATIC_CAST(ptrdiff_t, off) < pbase()) {

      setp(seeklow, epptr());

      pbump((int)off);

    }

    else {

      setp(pbase(), epptr());

      pbump((int)(off - (pbase() - seeklow)));

    }

  }

  if (do_get) {

    if (off <= egptr() - seeklow)

      setg(seeklow, seeklow + __STATIC_CAST(ptrdiff_t, off), egptr());

    else if (off <= pptr() - seeklow)

      setg(seeklow, seeklow + __STATIC_CAST(ptrdiff_t, off), pptr());

    else

      setg(seeklow, seeklow + __STATIC_CAST(ptrdiff_t, off), epptr());

  }

  return pos_type(newoff);

}

strstreambuf::pos_type

strstreambuf::seekpos(pos_type pos, ios_base::openmode mode) {

  return seekoff(pos - pos_type(off_type(0)), ios_base::beg, mode);

}

char* strstreambuf::_M_alloc(size_t n) {

  if (_M_alloc_fun)

    return __STATIC_CAST(char*,_M_alloc_fun(n));

  else

    return new char[n];

}

void strstreambuf::_M_free(char* p) {

  if (p) {

    if (_M_free_fun)

      _M_free_fun(p);

    else

      delete[] p;

  }

}

void strstreambuf::_M_setup(char* get, char* put, streamsize n) {

  if (get) {

    size_t N = n > 0 ? size_t(n) : n == 0 ? strlen(get) : size_t(INT_MAX);

    if (put) {

      setg(get, get, get + N);

      setp(put, put + N);

    }

    else {

      setg(get, get, get + N);

    }

  }

}

//----------------------------------------------------------------------

// Class istrstream

istrstream::istrstream(char* s)

  : basic_istream<char, char_traits<char> >(0), _M_buf(s, 0) {

  this->init(&_M_buf);

}

istrstream::istrstream(const char* s)

  : basic_istream<char, char_traits<char> >(0), _M_buf(s, 0) {

  this->init(&_M_buf);

}

istrstream::istrstream(char* s, streamsize n)

  : basic_istream<char, char_traits<char> >(0), _M_buf(s, n) {

  this->init(&_M_buf);

}

istrstream::istrstream(const char* s, streamsize n)

  : basic_istream<char, char_traits<char> >(0), _M_buf(s, n) {

  this->init(&_M_buf);

}

istrstream::~istrstream() {}

strstreambuf* istrstream::rdbuf() const {

  return __CONST_CAST(strstreambuf*,&_M_buf);

}

char* istrstream::str() { return _M_buf.str(); }

//----------------------------------------------------------------------

// Class ostrstream

ostrstream::ostrstream()

  : basic_ostream<char, char_traits<char> >(0), _M_buf() {

  basic_ios<char, char_traits<char> >::init(&_M_buf);

}

ostrstream::ostrstream(char* s, int n, ios_base::openmode mode)

  : basic_ostream<char, char_traits<char> >(0),

    _M_buf(s, n, mode & ios_base::app ? s + strlen(s) : s) {

  basic_ios<char, char_traits<char> >::init(&_M_buf);

}

ostrstream::~ostrstream() {}

strstreambuf* ostrstream::rdbuf() const {

  return __CONST_CAST(strstreambuf*,&_M_buf);

}

void ostrstream::freeze(bool freezeflag) {

  _M_buf.freeze(freezeflag);

}

char* ostrstream::str() {

  return _M_buf.str();

}

int ostrstream::pcount() const {

  return _M_buf.pcount();

}

//----------------------------------------------------------------------

// Class strstream

strstream::strstream()

  : basic_iostream<char, char_traits<char> >(0), _M_buf() {

  basic_ios<char, char_traits<char> >::init(&_M_buf);

}

strstream::strstream(char* s, int n, ios_base::openmode mode)

  : basic_iostream<char, char_traits<char> >(0),

    _M_buf(s, n, mode & ios_base::app ? s + strlen(s) : s) {

  basic_ios<char, char_traits<char> >::init(&_M_buf);

}

strstream::~strstream() {}

strstreambuf* strstream::rdbuf() const {

  return __CONST_CAST(strstreambuf*,&_M_buf);

}

void strstream::freeze(bool freezeflag) {

  _M_buf.freeze(freezeflag);

}

int strstream::pcount() const {

  return _M_buf.pcount();

}

char* strstream::str() {

  return _M_buf.str();

}

_STLP_END_NAMESPACE

// Local Variables:

// mode:C++

// End: