1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License, Version 1.0 only
6 * (the "License").  You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22/*	Copyright (c) 1988 AT&T	*/
23/*	  All Rights Reserved  	*/
24
25
26/*
27 * Copyright (c) 1999 by Sun Microsystems, Inc.
28 * All rights reserved.
29 */
30
31#pragma ident	"%Z%%M%	%I%	%E% SMI"
32
33/*
34 *	cscope - interactive C symbol or text cross-reference
35 *
36 *	command history
37 */
38
39#include <stdio.h>
40#include "global.h"
41
42HISTORY *head, *tail, *current;
43
44/* add a cmd to the history list */
45void
46addcmd(int f, char *s)
47{
48	HISTORY *h;
49
50	h = (HISTORY *)mymalloc(sizeof (HISTORY));
51	if (tail) {
52		tail->next = h;
53		h->next = 0;
54		h->previous = tail;
55		tail = h;
56	} else {
57		head = tail = h;
58		h->next = h->previous = 0;
59	}
60	h->field = f;
61	h->text = stralloc(s);
62	current = 0;
63}
64
65/* return previous history item */
66
67HISTORY *
68prevcmd(void)
69{
70	if (current) {
71		if (current->previous)	/* stay on first item */
72			return (current = current->previous);
73		else
74			return (current);
75	} else if (tail)
76		return (current = tail);
77	else
78		return (NULL);
79}
80
81/* return next history item */
82
83HISTORY *
84nextcmd(void)
85{
86	if (current) {
87		if (current->next)	/* stay on first item */
88			return (current = current->next);
89		else
90			return (current);
91	} else
92		return (NULL);
93}
94
95/* reset current to tail */
96
97void
98resetcmd(void)
99{
100	current = 0;
101}
102
103HISTORY *
104currentcmd(void)
105{
106	return (current);
107}
108