/*
 *  R : A Computer Langage for Statistical Data Analysis
 *  Copyright (C) 1997  Robert Gentleman and Ross Ihaka
 *
 *  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., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

/*
 *  I/O Support for Consoles and Character Vectors
 *
 *  This code provides analogues for the stdio routines "fgetc" and
 *  "ungetc" for "consoles" and character vectors.  These routines
 *  are used for parsing input from the console window and character
 *  vectors.
 */

#include <stdio.h>
#include "Defn.h"

#define IOBSIZE 4096

typedef struct BufferListItem {
	char			buf[IOBSIZE];
	struct BufferListItem	*next;
} BufferListItem;

typedef struct IoBuffer {
	BufferListItem	*start_buf;		/* First buffer item */
	BufferListItem	*write_buf;		/* Write pointer location */
	char		*write_ptr;		/* Write pointer location */
	int		 write_offset;		/* Write pointer location */
	BufferListItem	*read_buf;		/* Read pointer location */
	char		*read_ptr;		/* Read pointer location */
	int		 read_offset;		/* Read pointer location */
} IoBuffer;


typedef struct TextBuffer {
	char	*vmax;				/* Memory stack top */
	char	*buf;				/* Line buffer */
	char	*bufp;				/* Line buffer location */
	SEXP	text;				/* String Vector */
	int	ntext;				/* Vector length */
	int	offset;				/* Offset within vector */
} TextBuffer;

/*- some of these really could be void */
int R_IoBufferInit(IoBuffer*);
int R_IoBufferFree(IoBuffer*);
int R_IoBufferReadReset(IoBuffer*);
int R_IoBufferWriteReset(IoBuffer*);
int R_IoBufferGetc(IoBuffer*);
int R_IoBufferUngetc(int, IoBuffer*);
int R_IoBufferPutc(int, IoBuffer*);
int R_IoBufferPuts(char*, IoBuffer*);

int R_TextBufferInit(TextBuffer*, SEXP);
int R_TextBufferFree(TextBuffer*);
int R_TextBufferGetc(TextBuffer*);
int R_TextBufferUngetc(int, TextBuffer*);
