The R Project SVN R

/*
 *  R : A Computer Language 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 {
    unsigned char           buf[IOBSIZE];
    struct BufferListItem   *next;
} BufferListItem;

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


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

#ifndef __MAIN__
extern
#endif
IoBuffer R_ConsoleIob;                  /* Console IO Buffer */

/*- 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*);