reade.c

来自「早期freebsd实现」· C语言 代码 · 共 85 行

/*-
 * Copyright (c) 1979, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#ifndef lint
static char sccsid[] = "@(#)READE.c	8.1 (Berkeley) 6/6/93";
#endif /* not lint */

#include "h00vars.h"

long
READE(curfile, name)

	register struct iorec	*curfile;
	char			*name;
{
	register short	*sptr;
	register int	len;
	register int	nextlen;
	register int	cnt;
	char		*cp;
	char		namebuf[NAMSIZ];
	int		retval;

	if (curfile->funit & FWRITE) {
		ERROR("%s: Attempt to read, but open for writing\n",
			curfile->pfname);
	}
	UNSYNC(curfile);
	retval = fscanf(curfile->fbuf,
	    "%*[ \t\n]%74[abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789]",
	    namebuf);
	if (retval == EOF) {
		ERROR("%s: Tried to read past end of file\n", curfile->pfname);
	}
	if (retval == 0)
		goto ename;
	for (len = 0; len < NAMSIZ && namebuf[len]; len++)
		/* void */;
	len++;
	sptr = (short *)name;
	cnt = *sptr++;
	cp = name + sizeof (short) + *sptr;
	do	{
		nextlen = *sptr++;
		nextlen = *sptr - nextlen;
		if (nextlen == len && RELEQ(len, namebuf, cp)) {
			return *((short *) name) - cnt;
		}
		cp += (int)nextlen;
	} while (--cnt);
ename:
	ERROR("Unknown name \"%s\" found on enumerated type read\n", namebuf);
	return 0;
}