freebsd-skq/lib/libstand/gets.c
John Baldwin b0d8ed7ad3 Fix an off-by-one buffer overflow in ngets().
Submitted by:	Bruce Can
MFC after:	1 month
2009-03-31 14:30:46 +00:00

113 lines
2.8 KiB
C

/* $NetBSD: gets.c,v 1.6 1995/10/11 21:16:57 pk Exp $ */
/*-
* Copyright (c) 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.
* 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.
*
* @(#)gets.c 8.1 (Berkeley) 6/11/93
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "stand.h"
/* gets() with constrained input length */
void
ngets(char *buf, int n)
{
int c;
char *lp;
for (lp = buf;;)
switch (c = getchar() & 0177) {
case '\n':
case '\r':
*lp = '\0';
putchar('\n');
return;
case '\b':
case '\177':
if (lp > buf) {
lp--;
putchar('\b');
putchar(' ');
putchar('\b');
}
break;
case 'r'&037: {
char *p;
putchar('\n');
for (p = buf; p < lp; ++p)
putchar(*p);
break;
}
case 'u'&037:
case 'w'&037:
lp = buf;
putchar('\n');
break;
default:
if ((n < 1) || ((lp - buf) < n - 1)) {
*lp++ = c;
putchar(c);
}
}
/*NOTREACHED*/
}
int
fgetstr(char *buf, int size, int fd)
{
char c;
int err, len;
size--; /* leave space for terminator */
len = 0;
while (size != 0) {
err = read(fd, &c, sizeof(c));
if (err < 0) /* read error */
return(-1);
if (err == 0) { /* EOF */
if (len == 0)
return(-1); /* nothing to read */
break;
}
if ((c == '\r') || /* line terminators */
(c == '\n'))
break;
*buf++ = c; /* keep char */
size--;
len++;
}
*buf = 0;
return(len);
}