freebsd-nq/usr.bin/grep/queue.c
Ed Maste b5fc583c27 bsdgrep: don't allow negative -A / -B / -C
Previously, when given a negative -A/-B/-C argument bsdgrep would
overflow the respective context flag(s) and exhibited surprising
behavior.

Fix this by removing unsignedness of Aflag/Bflag and erroring out if
we're given a value < 0.  Also adjust the type used to track 'tail'
context in procfile() so that it accurately reflects the Aflag value
rather than overflowing and losing trailing context.

This also fixes an inconsistency previously existing between -n and
-C "n" behavior.  They are now both limited to LLONG_MAX, to be
consistent.

Add some test cases to make sure grep errors out properly for both
negative context values as well as non-numeric context values rather
than giving bogus matches.

Submitted by:	Kyle Evans <kevans91@ksu.edu>
Reviewed by:	cem
Differential Revision:	https://reviews.freebsd.org/D10675
2017-05-15 17:51:01 +00:00

119 lines
2.9 KiB
C

/* $NetBSD: queue.c,v 1.5 2011/08/31 16:24:57 plunky Exp $ */
/* $FreeBSD$ */
/*-
* Copyright (c) 1999 James Howard and Dag-Erling Coïdan Smørgrav
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
*/
/*
* A really poor man's queue. It does only what it has to and gets out of
* Dodge. It is used in place of <sys/queue.h> to get a better performance.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/queue.h>
#include <stdlib.h>
#include <string.h>
#include "grep.h"
struct qentry {
STAILQ_ENTRY(qentry) list;
struct str data;
};
static STAILQ_HEAD(, qentry) queue = STAILQ_HEAD_INITIALIZER(queue);
static long long count;
static struct qentry *dequeue(void);
/*
* Enqueue another line; return true if we've dequeued a line as a result
*/
bool
enqueue(struct str *x)
{
struct qentry *item;
item = grep_malloc(sizeof(struct qentry));
item->data.dat = grep_malloc(sizeof(char) * x->len);
item->data.len = x->len;
item->data.line_no = x->line_no;
item->data.off = x->off;
memcpy(item->data.dat, x->dat, x->len);
item->data.file = x->file;
STAILQ_INSERT_TAIL(&queue, item, list);
if (++count > Bflag) {
item = dequeue();
free(item->data.dat);
free(item);
return (true);
}
return (false);
}
static struct qentry *
dequeue(void)
{
struct qentry *item;
item = STAILQ_FIRST(&queue);
if (item == NULL)
return (NULL);
STAILQ_REMOVE_HEAD(&queue, list);
--count;
return (item);
}
void
printqueue(void)
{
struct qentry *item;
while ((item = dequeue()) != NULL) {
grep_printline(&item->data, '-');
free(item->data.dat);
free(item);
}
}
void
clearqueue(void)
{
struct qentry *item;
while ((item = dequeue()) != NULL) {
free(item->data.dat);
free(item);
}
}