1/*	$NetBSD: queue.c,v 1.5 2011/08/31 16:24:57 plunky Exp $	*/
2/*	$FreeBSD: head/usr.bin/grep/queue.c 211496 2010-08-19 09:28:59Z des $	*/
3/*-
4 * Copyright (c) 1999 James Howard and Dag-Erling Coïdan Smørgrav
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29/*
30 * A really poor man's queue.  It does only what it has to and gets out of
31 * Dodge.  It is used in place of <sys/queue.h> to get a better performance.
32 */
33
34#if HAVE_NBTOOL_CONFIG_H
35#include "nbtool_config.h"
36#endif
37
38#include <sys/cdefs.h>
39__RCSID("$NetBSD: queue.c,v 1.5 2011/08/31 16:24:57 plunky Exp $");
40
41#include <sys/param.h>
42#include <sys/queue.h>
43
44#include <stdlib.h>
45#include <string.h>
46
47#include "grep.h"
48
49struct qentry {
50	STAILQ_ENTRY(qentry)	list;
51	struct str	 	data;
52};
53
54static STAILQ_HEAD(, qentry)	queue = STAILQ_HEAD_INITIALIZER(queue);
55static unsigned long long	count;
56
57static struct qentry	*dequeue(void);
58
59void
60enqueue(struct str *x)
61{
62	struct qentry *item;
63
64	item = grep_malloc(sizeof(struct qentry));
65	item->data.dat = grep_malloc(sizeof(char) * x->len);
66	item->data.len = x->len;
67	item->data.line_no = x->line_no;
68	item->data.off = x->off;
69	memcpy(item->data.dat, x->dat, x->len);
70	item->data.file = x->file;
71
72	STAILQ_INSERT_TAIL(&queue, item, list);
73
74	if (++count > Bflag) {
75		item = dequeue();
76		free(item->data.dat);
77		free(item);
78	}
79}
80
81static struct qentry *
82dequeue(void)
83{
84	struct qentry *item;
85
86	item = STAILQ_FIRST(&queue);
87	if (item == NULL)
88		return (NULL);
89
90	STAILQ_REMOVE_HEAD(&queue, list);
91	--count;
92	return (item);
93}
94
95void
96printqueue(void)
97{
98	struct qentry *item;
99
100	while ((item = dequeue()) != NULL) {
101		printline(&item->data, '-', NULL, 0);
102		free(item->data.dat);
103		free(item);
104	}
105}
106
107void
108clearqueue(void)
109{
110	struct qentry *item;
111
112	while ((item = dequeue()) != NULL) {
113		free(item->data.dat);
114		free(item);
115	}
116}
117