diff options
Diffstat (limited to 'libstdc++-v3/include/std/std_fstream.h')
| -rw-r--r-- | libstdc++-v3/include/std/std_fstream.h | 76 |
1 files changed, 40 insertions, 36 deletions
diff --git a/libstdc++-v3/include/std/std_fstream.h b/libstdc++-v3/include/std/std_fstream.h index 7cc0dbd8e1f..605fad22b3e 100644 --- a/libstdc++-v3/include/std/std_fstream.h +++ b/libstdc++-v3/include/std/std_fstream.h @@ -137,19 +137,18 @@ namespace std * @endif */ bool _M_buf_allocated; - + + // _M_reading == false && _M_writing == false for 'uncommitted' mode; + // _M_reading == true for 'read' mode; + // _M_writing == true for 'write' mode; + // + // NB: _M_reading == true && _M_writing == true is unused. + bool _M_reading; + bool _M_writing; + // XXX Needed? bool _M_last_overflowed; - // The position in the buffer corresponding to the external file - // pointer. - /** - * @if maint - * @doctodo - * @endif - */ - char_type* _M_filepos; - //@{ /** * @if maint @@ -175,8 +174,8 @@ namespace std { if (!_M_pback_init) { - _M_pback_cur_save = this->_M_in_cur; - _M_pback_end_save = this->_M_in_end; + _M_pback_cur_save = this->gptr(); + _M_pback_end_save = this->egptr(); this->setg(&_M_pback, &_M_pback, &_M_pback + 1); _M_pback_init = true; } @@ -191,7 +190,7 @@ namespace std if (_M_pback_init) { // Length _M_in_cur moved in the pback buffer. - _M_pback_cur_save += this->_M_in_cur != this->_M_in_beg; + _M_pback_cur_save += this->gptr() != this->eback(); this->setg(this->_M_buf, _M_pback_cur_save, _M_pback_end_save); _M_pback_init = false; } @@ -365,23 +364,23 @@ namespace std sync() { int __ret = 0; - const bool __testput = this->_M_out_beg < this->_M_out_lim; // Make sure that the internal buffer resyncs its idea of // the file position with the external file. - if (__testput) + // NB: _M_file.sync() will be called within. + if (this->pbase() < this->pptr()) { - // Need to restore current position after the write. - const off_type __off = this->_M_out_cur - this->_M_out_lim; - - // _M_file.sync() will be called within. - if (traits_type::eq_int_type(this->overflow(), traits_type::eof())) + int_type __tmp = this->overflow(); + if (traits_type::eq_int_type(__tmp, traits_type::eof())) __ret = -1; - else if (__off) - _M_file.seekoff(__off, ios_base::cur); + else + { + _M_set_buffer(-1); + _M_reading = false; + _M_writing = false; + } } - else - _M_file.sync(); + _M_last_overflowed = false; return __ret; } @@ -398,9 +397,10 @@ namespace std streamsize __ret = 0; if (this->_M_pback_init) { - if (__n && this->_M_in_cur == this->_M_in_beg) + if (__n && this->gptr() == this->eback()) { - *__s++ = *this->_M_in_cur++; + *__s++ = *this->gptr(); + this->gbump(1); __ret = 1; } _M_destroy_pback(); @@ -427,10 +427,13 @@ namespace std _M_output_unshift(); // This function sets the pointers of the internal buffer, both get - // and put areas. Typically, __off == _M_in_end - _M_in_beg upon - // _M_underflow; __off == 0 upon overflow, seekoff, open, setbuf. + // and put areas. Typically: + // + // __off == egptr() - eback() upon underflow/uflow ('read' mode); + // __off == 0 upon overflow ('write' mode); + // __off == -1 upon open, setbuf, seekoff/pos ('uncommitted' mode). // - // NB: _M_out_end - _M_out_beg == _M_buf_size - 1, since _M_buf_size + // NB: epptr() - pbase() == _M_buf_size - 1, since _M_buf_size // reflects the actual allocated memory and the last cell is reserved // for the overflow char of a full put area. void @@ -439,14 +442,15 @@ namespace std const bool __testin = this->_M_mode & ios_base::in; const bool __testout = this->_M_mode & ios_base::out; - if (__testin) + if (__testin && __off > 0) this->setg(this->_M_buf, this->_M_buf, this->_M_buf + __off); - if (__testout && this->_M_buf_size > 1) - { - this->setp(this->_M_buf, this->_M_buf + this->_M_buf_size - 1); - this->_M_out_lim += __off; - } - _M_filepos = this->_M_buf + __off; + else + this->setg(this->_M_buf, this->_M_buf, this->_M_buf); + + if (__testout && __off == 0 && this->_M_buf_size > 1 ) + this->setp(this->_M_buf, this->_M_buf + this->_M_buf_size - 1); + else + this->setp(NULL, NULL); } }; |
