92 // Precondition: gptr() >= egptr().  Returns a character, if one is available.

    93 template <class _CharT, class _Traits, class _Alloc>

    94 __BSB_int_type__

    95 basic_stringbuf<_CharT, _Traits, _Alloc>::underflow() {

    96   return this->gptr() != this->egptr()

    97     ? _Traits::to_int_type(*this->gptr())

    98     : _Traits::eof();

    99 }

   101 // Precondition: gptr() >= egptr().

   102 template <class _CharT, class _Traits, class _Alloc>

   103 __BSB_int_type__

   104 basic_stringbuf<_CharT, _Traits, _Alloc>::uflow() {

   105   if (this->gptr() != this->egptr()) {

   106     int_type __c = _Traits::to_int_type(*this->gptr());

   107     this->gbump(1);

   108     return __c;

   109   }

   110   else

   111     return _Traits::eof();

   112 }

   114 template <class _CharT, class _Traits, class _Alloc>

   115 __BSB_int_type__

   116 basic_stringbuf<_CharT, _Traits, _Alloc>::pbackfail(int_type __c) {

   117   if (this->gptr() != this->eback()) {

   118     if (!_Traits::eq_int_type(__c, _Traits::eof())) {

   119       if (_Traits::eq(_Traits::to_char_type(__c), this->gptr()[-1])) {

   120         this->gbump(-1);

   121         return __c;

   122       }

   123       else if (_M_mode & ios_base::out) {

   124         this->gbump(-1);

   125         *this->gptr() = _Traits::to_char_type(__c);

   126         return __c;

   127       }

   128       else

   129         return _Traits::eof();

   130     }

   131     else {

   132       this->gbump(-1);

   133       return _Traits::not_eof(__c);

   134     }

   135   }

   136   else

   137     return _Traits::eof();

   138 }

   139 

   140 template <class _CharT, class _Traits, class _Alloc>

   141 __BSB_int_type__

   142 basic_stringbuf<_CharT, _Traits, _Alloc>::overflow(int_type __c) {

   143   // fbp : reverse order of "ifs" to pass Dietmar's test.

   144   // Apparently, standard allows overflow with eof even for read-only streams.

   145   if (!_Traits::eq_int_type(__c, _Traits::eof())) {

   146     if (_M_mode & ios_base::out) {

   147       if (!(_M_mode & ios_base::in)) {

   148         // It's a write-only streambuf, so we can use special append buffer.

   149         if (this->pptr() == this->epptr())

   150           this->_M_append_buffer();

   151 

   152         if (this->pptr() != this->epptr()) {

   153           *this->pptr() = _Traits::to_char_type(__c);

   154           this->pbump(1);

   155           return __c;

   156         }

   157         else

   158           return _Traits::eof();

   159       }

   160       else {

   161         // We're not using a special append buffer, just the string itself.

   162         if (this->pptr() == this->epptr()) {

   163           ptrdiff_t __offset = this->gptr() - this->eback();

   164           _M_str.push_back(_Traits::to_char_type(__c));

   165 

   166           _CharT* __data_ptr = __CONST_CAST(_CharT*,_M_str.data());

   167           size_t __data_size = _M_str.size();

   168 

   169           this->setg(__data_ptr, __data_ptr + __offset, __data_ptr+__data_size);

   170           this->setp(__data_ptr, __data_ptr + __data_size);

   171           this->pbump((int)__data_size);

   172           return __c;

   173         }

   174         else {

   175           *this->pptr() = _Traits::to_char_type(__c);

   176           this->pbump(1);

   177           return __c;

   178         }

   179       }

   180     }

   181     else                          // Overflow always fails if it's read-only

   182       return _Traits::eof();

   183   }

   184   else                        // __c is EOF, so we don't have to do anything

   185     return _Traits::not_eof(__c);

   186 }

   187 

   188 template <class _CharT, class _Traits, class _Alloc>

   189 streamsize

   190 basic_stringbuf<_CharT, _Traits, _Alloc>::xsputn(const char_type* __s,

   191                                                  streamsize __n) {

   192   streamsize __nwritten = 0;

   193 

   194   if ((_M_mode & ios_base::out) && __n > 0) {

   195     // If the put pointer is somewhere in the middle of the string,

   196     // then overwrite instead of append.

   197     if (this->pbase() == _M_str.data() ) {

   198       ptrdiff_t __avail = _M_str.data() + _M_str.size() - this->pptr();

   199       if (__avail > __n) {

   200         _Traits::copy(this->pptr(), __s, __STATIC_CAST(size_t, __n));

   201         this->pbump((int)__n);

   202         return __n;

   203       }

   204       else {

   205         _Traits::copy(this->pptr(), __s, __avail);

   206         __nwritten += __avail;

   207         __n -= __avail;

   208         __s += __avail;

   209         this->setp(_M_Buf, _M_Buf + __STATIC_CAST(int,_S_BufSiz));

   210       }

   211     }

   212 

   213     // At this point we know we're appending.

   214     if (_M_mode & ios_base::in) {

   215       ptrdiff_t __get_offset = this->gptr() - this->eback();

   216       _M_str.append(__s, __s + __STATIC_CAST(ptrdiff_t, __n));

   217 

   218       _CharT* __data_ptr = __CONST_CAST(_CharT*, _M_str.data());

   219       size_t __data_size = _M_str.size();

   220 

   221       this->setg(__data_ptr, __data_ptr + __get_offset, __data_ptr + __data_size);

   222       this->setp(__data_ptr, __data_ptr + __data_size);

   223       this->pbump((int)__data_size);

   224     }

   225     else {

   226       _M_append_buffer();

   227       _M_str.append(__s, __s + __STATIC_CAST(ptrdiff_t, __n));

   228     }

   229 

   230     __nwritten += __n;

   231   }

   232 

   233   return __nwritten;

   234 }

   235 

   236 template <class _CharT, class _Traits, class _Alloc>

   237 streamsize

   238 basic_stringbuf<_CharT, _Traits, _Alloc>::_M_xsputnc(char_type __c,

   239                                                      streamsize __n) {

   240   streamsize __nwritten = 0;

   241 

   242   if ((_M_mode & ios_base::out) && __n > 0) {

   243     // If the put pointer is somewhere in the middle of the string,

   244     // then overwrite instead of append.

   245     if (this->pbase() == _M_str.data()) {

   246       ptrdiff_t __avail = _M_str.data() + _M_str.size() - this->pptr();

   247       if (__avail > __n) {

   248         _Traits::assign(this->pptr(), __STATIC_CAST(size_t, __n), __c);

   249         this->pbump(__STATIC_CAST(int, __n));

   250         return __n;

   251       }

   252       else {

   253         _Traits::assign(this->pptr(), __avail, __c);

   254         __nwritten += __avail;

   255         __n -= __avail;

   256         this->setp(_M_Buf, _M_Buf + __STATIC_CAST(int,_S_BufSiz));

   257       }

   258     }

   259 

   260     // At this point we know we're appending.

   261     size_t __app_size = sizeof(streamsize) > sizeof(size_t) ? __STATIC_CAST(size_t, (min)(__n, __STATIC_CAST(streamsize, _M_str.max_size())))

   262                                                             : __STATIC_CAST(size_t, __n);

   263     if (this->_M_mode & ios_base::in) {

   264       ptrdiff_t __get_offset = this->gptr() - this->eback();

   265       _M_str.append(__app_size, __c);

   266 

   267       _CharT* __data_ptr = __CONST_CAST(_CharT*,_M_str.data());

   268       size_t __data_size = _M_str.size();

   269 

   270       this->setg(__data_ptr, __data_ptr + __get_offset, __data_ptr + __data_size);

   271       this->setp(__data_ptr, __data_ptr + __data_size);

   272       this->pbump((int)__data_size);

   273     }

   274     else {

   275       _M_append_buffer();

   276       _M_str.append(__app_size, __c);

   277     }

   278 

   279     __nwritten += __app_size;

   280   }

   281 

   282   return __nwritten;

   283 }

   284 

   285 // According to the C++ standard the effects of setbuf are implementation

   286 // defined, except that setbuf(0, 0) has no effect.  In this implementation,

   287 // setbuf(<anything>, n), for n > 0, calls reserve(n) on the underlying

   288 // string.

   289 template <class _CharT, class _Traits, class _Alloc>

   290 basic_streambuf<_CharT, _Traits>*

   291 basic_stringbuf<_CharT, _Traits, _Alloc>::setbuf(_CharT*, streamsize __n) {

   292   if (__n > 0) {

   293     bool __do_get_area = false;

   294     bool __do_put_area = false;

   295     ptrdiff_t __offg = 0;

   296     ptrdiff_t __offp = 0;

   297 

   298     if (this->pbase() == _M_str.data()) {

   299       __do_put_area = true;

   300       __offp = this->pptr() - this->pbase();

   301     }

   302 

   303     if (this->eback() == _M_str.data()) {

   304       __do_get_area = true;

   305       __offg = this->gptr() - this->eback();

   306     }

   307 

   308     if ((_M_mode & ios_base::out) && !(_M_mode & ios_base::in))

   309       _M_append_buffer();

   310 

   311     _M_str.reserve(sizeof(streamsize) > sizeof(size_t) ? __STATIC_CAST(size_t, (min)(__n, __STATIC_CAST(streamsize, _M_str.max_size())))

   312                                                        : __STATIC_CAST(size_t, __n));

   313 

   314     _CharT* __data_ptr = __CONST_CAST(_CharT*, _M_str.data());

   315     size_t __data_size = _M_str.size();

   316 

   317     if (__do_get_area) {

   318       this->setg(__data_ptr, __data_ptr + __offg, __data_ptr + __data_size);

   319     }

   320 

   321     if (__do_put_area) {

   322       this->setp(__data_ptr, __data_ptr + __data_size);

   323       this->pbump((int)__offp);

   324     }

   325   }

   326 

   327   return this;

   328 }

   329 

   330 template <class _CharT, class _Traits, class _Alloc>

   331 __BSB_pos_type__

   332 basic_stringbuf<_CharT, _Traits, _Alloc>

   333   ::seekoff(off_type __off,

   334             ios_base::seekdir __dir,

   335             ios_base::openmode __mode) {

   336   __mode &= _M_mode;

   337 

   338   bool __imode  = (__mode & ios_base::in) != 0;

   339   bool __omode = (__mode & ios_base::out) != 0;

   340 

   341   if ( !(__imode || __omode) )

   342     return pos_type(off_type(-1));

   343 

   344   if ( (__imode && (this->gptr() == 0)) || (__omode && (this->pptr() == 0)) )

   345     return pos_type(off_type(-1));

   346 

   347 #ifndef SYMBIAN_OE_ENHANCED_LOCALE_SUPPORT

   348   if ((_M_mode & ios_base::out) && !(_M_mode & ios_base::in))

   349     _M_append_buffer();

   350 #endif

   351 

   352   streamoff __newoff;

   353   switch(__dir) {

   354   case ios_base::beg:

   355     __newoff = 0;

   356     break;

   357   case ios_base::end:

   358     __newoff = _M_str.size();

   359     break;

   360   case ios_base::cur:

   361     __newoff = __imode ? this->gptr() - this->eback() : this->pptr() - this->pbase();

   362 #ifdef SYMBIAN_OE_ENHANCED_LOCALE_SUPPORT

   363       if ( __off == 0 ) {

   364         return pos_type(__newoff);

   365       }

   366 #endif

   367     break;

   368   default:

   369     return pos_type(off_type(-1));

   370   }

   371 

   372   __off += __newoff;

   373 #ifdef SYMBIAN_OE_ENHANCED_LOCALE_SUPPORT

   374   _CharT* __data_ptr = __CONST_CAST(_CharT*, _M_str.data());

   375   size_t __data_size = _M_str.size();

   376 #endif

   377 

   378   if (__imode) {

   379     ptrdiff_t __n = this->egptr() - this->eback();

   380 

   381     if (__off < 0 || __off > __n)

   382       return pos_type(off_type(-1));

   383     this->setg(this->eback(), this->eback() + __STATIC_CAST(ptrdiff_t, __off),

   384                               this->eback() + __STATIC_CAST(ptrdiff_t, __n));

   385   }

   386 

   387   if (__omode) {

   388     ptrdiff_t __n = this->epptr() - this->pbase();

   389 

   390     if (__off < 0 || __off > __n)

   391       return pos_type(off_type(-1));

   392 #ifdef SYMBIAN_OE_ENHANCED_LOCALE_SUPPORT

   393  this->setp(__data_ptr, __data_ptr+__data_size);

   394 #else

   395     this->setp(this->pbase(), this->pbase() + __n);

   396 #endif

   397     this->pbump((int)__off);

   398   }

   399 

   400   return pos_type(__off);

   401 }

   402 

   403 template <class _CharT, class _Traits, class _Alloc>

   404 __BSB_pos_type__

   405 basic_stringbuf<_CharT, _Traits, _Alloc>

   406   ::seekpos(pos_type __pos, ios_base::openmode __mode) {

   407   __mode &= _M_mode;

   408 

   409   bool __imode  = (__mode & ios_base::in) != 0;

   410   bool __omode = (__mode & ios_base::out) != 0;

   411 

   412   if ( !(__imode || __omode) )

   413     return pos_type(off_type(-1));

   414 

   415   if ( (__imode && (this->gptr() == 0)) || (__omode && (this->pptr() == 0)) )

   416     return pos_type(off_type(-1));

   417 

   418   const off_type __n = __pos - pos_type(off_type(0));

   419   if ((_M_mode & ios_base::out) && !(_M_mode & ios_base::in))

   420     _M_append_buffer();

   421 

   422   if (__imode) {

   423     if (__n < 0 || __n > this->egptr() - this->eback())

   424       return pos_type(off_type(-1));

   425     this->setg(this->eback(), this->eback() + __STATIC_CAST(ptrdiff_t, __n), this->egptr());

   426   }

   427 

   428   if (__omode) {

   429     if (__n < 0 || size_t(__n) > _M_str.size())

   430       return pos_type(off_type(-1));

   431 

   432     _CharT* __data_ptr = __CONST_CAST(_CharT*,_M_str.data());

   433     size_t __data_size = _M_str.size();

   434 

   435     this->setp(__data_ptr, __data_ptr+__data_size);

   436     this->pbump((int)__n);

   437   }

   438 

   439   return __pos;

   440 }