| /******************************************************************************* |
| * $Revision: 1.2 $ |
| * $Date: 2001/09/11 06:19:36 $ |
| * $Author: vyzo $ |
| * |
| * Contents: A streambuf which uses the GNU readline library for line I/O |
| * (c) 2001 by Dimitris Vyzovitis [vyzo@media.mit.edu] |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public |
| * License along with this program; if not, write to the Free |
| * Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, |
| * MA 02111-1307 USA |
| * |
| ******************************************************************************/ |
| |
| #ifndef _READLINEBUF_H_ |
| #define _READLINEBUF_H_ |
| |
| #include <iostream> |
| #include <cstring> |
| #include <cassert> |
| #include <cstdlib> |
| #include <cstdio> |
| |
| #include <readline/readline.h> |
| #include <readline/history.h> |
| |
| #if (defined __GNUC__) && (__GNUC__ < 3) |
| #include <streambuf.h> |
| #else |
| #include <streambuf> |
| using std::streamsize; |
| using std::streambuf; |
| #endif |
| |
| class readlinebuf : public streambuf { |
| public: |
| #if (defined __GNUC__) && (__GNUC__ < 3) |
| typedef char char_type; |
| typedef int int_type; |
| typedef streampos pos_type; |
| typedef streamoff off_type; |
| #endif |
| static const int_type eof = EOF; // this is -1 |
| static const int_type not_eof = 0; |
| |
| private: |
| const char* prompt_; |
| bool history_; |
| char* line_; |
| int low_; |
| int high_; |
| |
| protected: |
| |
| virtual int_type showmanyc() const { return high_ - low_; } |
| |
| virtual streamsize xsgetn( char_type* buf, streamsize n ) { |
| int rd = n > (high_ - low_)? (high_ - low_) : n; |
| memcpy( buf, line_, rd ); |
| low_ += rd; |
| |
| if ( rd < n ) { |
| low_ = high_ = 0; |
| free( line_ ); // free( NULL ) is a noop |
| line_ = readline( prompt_ ); |
| if ( line_ ) { |
| high_ = strlen( line_ ); |
| if ( history_ && high_ ) add_history( line_ ); |
| rd += xsgetn( buf + rd, n - rd ); |
| } |
| } |
| |
| return rd; |
| } |
| |
| virtual int_type underflow() { |
| if ( high_ == low_ ) { |
| low_ = high_ = 0; |
| free( line_ ); // free( NULL ) is a noop |
| line_ = readline( prompt_ ); |
| if ( line_ ) { |
| high_ = strlen( line_ ); |
| if ( history_ && high_ ) add_history( line_ ); |
| } |
| } |
| |
| if ( low_ < high_ ) return line_[low_]; |
| else return eof; |
| } |
| |
| virtual int_type uflow() { |
| int_type c = underflow(); |
| if ( c != eof ) ++low_; |
| return c; |
| } |
| |
| virtual int_type pbackfail( int_type c = eof ) { |
| if ( low_ > 0 ) --low_; |
| else if ( c != eof ) { |
| if ( high_ > 0 ) { |
| char* nl = (char*)realloc( line_, high_ + 1 ); |
| if ( nl ) { |
| line_ = (char*)memcpy( nl + 1, line_, high_ ); |
| high_ += 1; |
| line_[0] = char( c ); |
| } else return eof; |
| } else { |
| assert( !line_ ); |
| line_ = (char*)malloc( sizeof( char ) ); |
| *line_ = char( c ); |
| high_ = 1; |
| } |
| } else return eof; |
| |
| return not_eof; |
| } |
| |
| public: |
| readlinebuf( const char* prompt = NULL, bool history = true ) |
| : prompt_( prompt ), history_( history ), |
| line_( NULL ), low_( 0 ), high_( 0 ) { |
| setbuf( 0, 0 ); |
| } |
| |
| |
| }; |
| |
| #endif |