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/*************************************************************************
** InputBuffer.h **
** **
** This file is part of dvisvgm -- the DVI to SVG converter **
** Copyright (C) 2005-2010 Martin Gieseking <martin.gieseking@uos.de> **
** **
** 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 3 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, see <http://www.gnu.org/licenses/>. **
*************************************************************************/
#ifndef INPUTBUFFER_H
#define INPUTBUFFER_H
#include <algorithm>
#include <cstring>
#include <istream>
#include <string>
#include <ostream>
#include "types.h"
struct InputBuffer
{
virtual ~InputBuffer () {}
virtual int get () =0;
virtual int peek () const =0;
virtual int peek (unsigned n) const =0;
virtual bool eof () const =0;
virtual void invalidate () =0;
};
class StreamInputBuffer : public InputBuffer
{
public:
StreamInputBuffer (std::istream &is, unsigned bufsize=1024);
~StreamInputBuffer ();
int get ();
int peek () const;
int peek (unsigned n) const;
bool eof () const {return pos() == _size1 && _size2 == 0;}
void invalidate () {_bufptr = _buf1+_size1; _size2 = 0;}
protected:
int fillBuffer (UInt8 *buf);
unsigned pos () const {return _bufptr-_buf1;}
private:
std::istream &_is;
const unsigned _bufsize; ///< maximal number of bytes each buffer can hold
UInt8 *_buf1; ///< pointer to first buffer
UInt8 *_buf2; ///< pointer to second buffer
unsigned _size1; ///< number of bytes in buffer 1
unsigned _size2; ///< number of bytes in buffer 2
UInt8 *_bufptr; ///< pointer to next byte to read
};
class StringInputBuffer : public InputBuffer
{
public:
StringInputBuffer (std::string &str) : _str(str), _pos(0) {}
int get () {return _pos < _str.length() ? _str[_pos++] : -1;}
int peek () const {return _pos < _str.length() ? _str[_pos] : -1;}
int peek (unsigned n) const {return _pos+n < _str.length() ? _str[_pos+n] : -1;}
bool eof () const {return _pos >= _str.length();}
void invalidate () {_pos = _str.length();}
private:
std::string &_str;
unsigned _pos;
};
class CharInputBuffer : public InputBuffer
{
public:
CharInputBuffer (const char *buf, unsigned size) : _pos(buf), _size(buf ? size : 0) {}
int get () {
if (_size <= 0)
return -1;
else {
_size--;
return *_pos++;
}
}
void assign (const char *buf, unsigned size) {
_pos = buf;
_size = size;
}
void assign (const char *buf) {assign(buf, std::strlen(buf));}
int peek () const {return _size > 0 ? *_pos : -1;}
int peek (unsigned n) const {return _size >= n ? _pos[n] : -1;}
bool eof () const {return _size <= 0;}
void invalidate () {_size = 0;}
private:
const char *_pos;
unsigned _size;
};
class SplittedCharInputBuffer : public InputBuffer
{
public:
SplittedCharInputBuffer (const char *buf1, unsigned s1, const char *buf2, unsigned s2);
int get ();
int peek () const;
int peek (unsigned n) const;
bool eof () const {return _size[_index] == 0;}
void invalidate () {_size[_index] = 0;}
private:
const char *_buf[2];
unsigned _size[2];
int _index;
};
class TextStreamInputBuffer : public StreamInputBuffer
{
public:
TextStreamInputBuffer (std::istream &is) : StreamInputBuffer(is), _line(1), _col(1) {}
int get ();
int line () const {return _line;}
int col () const {return _col;}
private:
int _line, _col;
};
#endif
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