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 
49 struct qentry {
50 	STAILQ_ENTRY(qentry)	list;
51 	struct str	 	data;
52 };
53 
54 static STAILQ_HEAD(, qentry)	queue = STAILQ_HEAD_INITIALIZER(queue);
55 static unsigned long long	count;
56 
57 static struct qentry	*dequeue(void);
58 
59 void
enqueue(struct str * x)60 enqueue(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 
81 static struct qentry *
dequeue(void)82 dequeue(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 
95 void
printqueue(void)96 printqueue(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 
107 void
clearqueue(void)108 clearqueue(void)
109 {
110 	struct qentry *item;
111 
112 	while ((item = dequeue()) != NULL) {
113 		free(item->data.dat);
114 		free(item);
115 	}
116 }
117