1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
|
/* ========================================================================== **
* ubi_dLinkList.c
*
* Copyright (C) 1997, 1998 by Christopher R. Hertel
*
* Email: crh@ubiqx.mn.org
* -------------------------------------------------------------------------- **
* This module implements simple doubly-linked lists.
* -------------------------------------------------------------------------- **
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the Free
* Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
* -------------------------------------------------------------------------- **
*
* Log: ubi_dLinkList.c,v
* Revision 0.8 1998/06/03 18:06:03 crh
* Further fiddling with sys_include.h, which has been moved from the .c file
* to the .h file.
*
* Revision 0.7 1998/06/02 01:38:47 crh
* Changed include file name from ubi_null.h to sys_include.h to make it
* more generic.
*
* Revision 0.6 1998/05/20 04:38:05 crh
* The C file now includes ubi_null.h. See ubi_null.h for more info.
*
* Revision 0.5 1998/03/10 02:55:00 crh
* Simplified the code and added macros for stack & queue manipulations.
*
* Revision 0.4 1998/01/03 01:53:56 crh
* Added ubi_dlCount() macro.
*
* Revision 0.3 1997/10/15 03:05:39 crh
* Added some handy type casting to the macros. Added AddHere and RemThis
* macros.
*
* Revision 0.2 1997/10/08 03:07:21 crh
* Fixed a few forgotten link-ups in Insert(), and fixed the AddHead()
* macro, which was passing the wrong value for <After> to Insert().
*
* Revision 0.1 1997/10/07 04:34:07 crh
* Initial Revision.
*
* -------------------------------------------------------------------------- **
* This module is similar to the ubi_sLinkList module, but it is neither a
* descendant type nor an easy drop-in replacement for the latter. One key
* difference is that the ubi_dlRemove() function removes the indicated node,
* while the ubi_slRemove() function (in ubi_sLinkList) removes the node
* *following* the indicated node.
*
* ========================================================================== **
*/
#include "ubi_dLinkList.h" /* Header for *this* module. */
/* ========================================================================== **
* Functions...
*/
ubi_dlListPtr ubi_dlInitList( ubi_dlListPtr ListPtr )
/* ------------------------------------------------------------------------ **
* Initialize a doubly-linked list header.
*
* Input: ListPtr - A pointer to the list structure that is to be
* initialized for use.
*
* Output: A pointer to the initialized list header (i.e., same as
* <ListPtr>).
*
* ------------------------------------------------------------------------ **
*/
{
ListPtr->Head = NULL;
ListPtr->Tail = NULL;
ListPtr->count = 0;
return( ListPtr );
} /* ubi_dlInitList */
ubi_dlNodePtr ubi_dlInsert( ubi_dlListPtr ListPtr,
ubi_dlNodePtr New,
ubi_dlNodePtr After )
/* ------------------------------------------------------------------------ **
* Insert a new node into the list.
*
* Input: ListPtr - A pointer to the list into which the node is to
* be inserted.
* New - Pointer to the new node.
* After - NULL, or a pointer to a node that is already in the
* list.
* If NULL, then <New> will be added at the head of the
* list, else it will be added following <After>.
*
* Output: A pointer to the node that was inserted into the list (i.e.,
* the same as <New>).
*
* ------------------------------------------------------------------------ **
*/
{
ubi_dlNodePtr PredNode = After ? After : (ubi_dlNodePtr)ListPtr;
New->Next = PredNode->Next;
New->Prev = After;
PredNode->Next = New;
if( New->Next )
New->Next->Prev = New;
else
ListPtr->Tail = New;
(ListPtr->count)++;
return( New );
} /* ubi_dlInsert */
ubi_dlNodePtr ubi_dlRemove( ubi_dlListPtr ListPtr, ubi_dlNodePtr Old )
/* ------------------------------------------------------------------------ **
* Remove a node from the list.
*
* Input: ListPtr - A pointer to the list from which <Old> is to be
* removed.
* Old - A pointer to the node that is to be removed from the
* list.
*
* Output: A pointer to the node that was removed (i.e., <Old>).
*
* ------------------------------------------------------------------------ **
*/
{
if( Old )
{
if( Old->Next )
Old->Next->Prev = Old->Prev;
else
ListPtr->Tail = Old->Prev;
if( Old->Prev )
Old->Prev->Next = Old->Next;
else
ListPtr->Head = Old->Next;
(ListPtr->count)--;
}
return( Old );
} /* ubi_dlRemove */
/* ================================ The End ================================= */
|
