summaryrefslogtreecommitdiff
path: root/source3/ubi_dLinkList.h
blob: 1facf92d3b1c1843cb66874943b1d03679e24edc (plain)
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
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
#ifndef ubi_dLinkList_H
#define ubi_dLinkList_H
/* ========================================================================== **
 *                              ubi_dLinkList.h
 *
 *  Copyright (C) 1997 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.
 *
 * -------------------------------------------------------------------------- **
 *
 * Revision 0.3  1997/10/15 03:04:31  crh
 * Added some handy type casting to the macros.  Added AddHere and RemThis
 * macros.
 *
 * Revision 0.2  1997/10/08 03:08:16  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 04:34:38  crh
 * Initial Revision.
 *
 *
 * ========================================================================== **
 */

#include <stdlib.h>


/* ========================================================================== **
 * Typedefs...
 *
 *  ubi_dlNode    - This is the basic node structure.
 *  ubi_dlNodePtr - Pointer to a node.
 *  ubi_dlList    - This is the list header structure.
 *  ubi_dlListPtr - Pointer to a List (i.e., a list header structure).
 *
 */

typedef struct ubi_dlListNode
  {
  struct ubi_dlListNode *Next;
  struct ubi_dlListNode *Prev;
  } ubi_dlNode;

typedef ubi_dlNode *ubi_dlNodePtr;

typedef struct
  {
  ubi_dlNodePtr Head;
  ubi_dlNodePtr Tail;
  unsigned long count;
  } ubi_dlList;

typedef ubi_dlList *ubi_dlListPtr;

/* ========================================================================== **
 * Macros...
 * 
 *  ubi_dlAddHead - Add a new node at the head of the list.
 *  ubi_dlAddTail - Add a new node at the tail of the list.
 *  ubi_dlAddHere - Add a node following the given node.
 *  ubi_dlRemHead - Remove the node at the head of the list, if any.
 *  ubi_dlRemTail - Remove the node at the tail of the list, if any.
 *  ubi_dlRemThis - Remove the indicated node.
 *  ubi_dlFirst   - Return a pointer to the first node in the list, if any.
 *  ubi_dlLast    - Return a pointer to the last node in the list, if any.
 *  ubi_dlNext    - Given a node, return a pointer to the next node.
 *  ubi_dlPrev    - Given a node, return a pointer to the previous node.
 *
 *  Note that all of these provide type casting of the parameters.  The
 *  Add and Rem macros are nothing more than nice front-ends to the
 *  Insert and Remove operations.
 *
 */

#define ubi_dlAddHead( L, N ) \
        ubi_dlInsert( (ubi_dlListPtr)(L), (ubi_dlNodePtr)(N), NULL )

#define ubi_dlAddTail( L, N ) \
        ubi_dlInsert( (ubi_dlListPtr)(L), \
                      (ubi_dlNodePtr)(N), \
                    (((ubi_dlListPtr)(L))->Tail) )

#define ubi_dlAddHere( L, N, P ) \
        ubi_dlInsert( (ubi_dlListPtr)(L), \
                      (ubi_dlNodePtr)(N), \
                      (ubi_dlNodePtr)(P) )

#define ubi_dlRemHead( L ) ubi_dlRemove( (ubi_dlListPtr)(L), \
                                         (((ubi_dlListPtr)(L))->Head) )

#define ubi_dlRemTail( L ) ubi_dlRemove( (ubi_dlListPtr)(L), \
                                         (((ubi_dlListPtr)(L))->Tail) )

#define ubi_dlRemThis( L, N ) ubi_dlRemove( (ubi_dlListPtr)(L), \
                                            (ubi_dlNodePtr)(N) )

#define ubi_dlFirst( L ) (((ubi_dlListPtr)(L))->Head)

#define ubi_dlLast( L )  (((ubi_dlListPtr)(L))->Tail)

#define ubi_dlNext( N )  (((ubi_dlNodePtr)(N))->Next)

#define ubi_dlPrev( N )  (((ubi_dlNodePtr)(N))->Prev)


/* ========================================================================== **
 * Function prototypes...
 */

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>).
   *
   * ------------------------------------------------------------------------ **
   */

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 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>).
   *
   * ------------------------------------------------------------------------ **
   */


/* ================================ The End ================================= */
#endif /* ubi_dLinkList_H */