fgetline.c

读取/刻录光盘的程序

/* @(#)fgetline.c	1.3 96/05/09 Copyright 1986 J. Schilling */
/*
 *	Copyright (c) 1986 J. Schilling
 */
/* 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, 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; see the file COPYING.  If not, write to
 * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. 
 */

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

/*
 * XXX should we check if HAVE_USG_STDIO is defined and
 * XXX use something line memccpy to speed things up ???
 */

int fgetline(f, buf, len)
	register	FILE	*f;
			char	*buf;
	register	int	len;
{
	register int	c	= '\0';
	register char	*bp	= buf;
	register int	nl	= '\n';

	down2(f, _IOREAD, _IORW);

	for(;;) {
		if((c = getc(f)) < 0)
			break;
		if(c == nl)
			break;
		if (--len > 0) {
			*bp++ = c;
		} else {
			/*
			 * Read up to end of line
			 */
			while ((c = getc(f)) >= 0 && c != nl)
				;
			break;
		}
	}
	*bp = '\0';
	/*
	 * If buffer is empty and we hit EOF, return EOF
	 */
	if(c < 0 && bp == buf)
		return (c);

	return (bp - buf);
}

int getline(buf, len)
	char	*buf;
	int	len;
{
	return (fgetline(stdin, buf, len));
}