xref: /openbsd-src/usr.bin/make/lst.lib/lstAppend.c (revision a28daedfc357b214be5c701aa8ba8adb29a7f1c2)
1 /*	$OpenPackages$ */
2 /*	$OpenBSD: lstAppend.c,v 1.19 2007/09/16 09:46:14 espie Exp $	*/
3 /*	$NetBSD: lstAppend.c,v 1.5 1996/11/06 17:59:31 christos Exp $	*/
4 
5 /*
6  * Copyright (c) 1988, 1989, 1990, 1993
7  *	The Regents of the University of California.  All rights reserved.
8  *
9  * This code is derived from software contributed to Berkeley by
10  * Adam de Boor.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 3. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 /*-
38  * LstAppend.c --
39  *	Add a new node with a new datum after an existing node
40  */
41 
42 #include "lstInt.h"
43 #include <sys/types.h>
44 #include <stddef.h>
45 #include "memory.h"
46 
47 /*-
48  *-----------------------------------------------------------------------
49  * Lst_Append --
50  *	Create a new node and add it to the given list after the given node.
51  *
52  * Side Effects:
53  *	A new ListNode is created and linked in to the List. The lastPtr
54  *	field of the List will be altered if ln is the last node in the
55  *	list. lastPtr and firstPtr will alter if the list was empty and
56  *	ln was NULL.
57  *
58  *-----------------------------------------------------------------------
59  */
60 void
61 Lst_Append(Lst l, LstNode after, void *d)
62 {
63 	LstNode	nLNode;
64 
65 	if (after == NULL && !Lst_IsEmpty(l))
66 		return;
67 
68 	if (after != NULL && Lst_IsEmpty(l))
69 		return;
70 
71 	PAlloc(nLNode, LstNode);
72 	nLNode->datum = d;
73 
74 	if (after == NULL) {
75 		nLNode->nextPtr = nLNode->prevPtr = NULL;
76 		l->firstPtr = l->lastPtr = nLNode;
77 	} else {
78 		nLNode->prevPtr = after;
79 		nLNode->nextPtr = after->nextPtr;
80 
81 		after->nextPtr = nLNode;
82 		if (nLNode->nextPtr != NULL)
83 			nLNode->nextPtr->prevPtr = nLNode;
84 
85 		if (after == l->lastPtr)
86 			l->lastPtr = nLNode;
87 	}
88 }
89 
90 void
91 Lst_AtEnd(Lst l, void *d)
92 {
93 	LstNode	ln;
94 
95 	PAlloc(ln, LstNode);
96 	ln->datum = d;
97 
98 	ln->prevPtr = l->lastPtr;
99 	ln->nextPtr = NULL;
100 	if (l->lastPtr == NULL)
101 		l->firstPtr = ln;
102 	else
103 		l->lastPtr->nextPtr = ln;
104 	l->lastPtr = ln;
105 }
106