xref: /trueos/contrib/ntp/include/isc/list.h (revision 118e757284cbb8fc4f43a713e892b41504b50a5f)
1 /*
2  * Copyright (C) 1997-2001  Internet Software Consortium.
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM
9  * DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL
10  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL
11  * INTERNET SOFTWARE CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT,
12  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING
13  * FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
14  * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
15  * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 /* $Id: list.h,v 1.19 2002/05/09 07:09:30 marka Exp $ */
19 
20 #ifndef ISC_LIST_H
21 #define ISC_LIST_H 1
22 #include <isc/boolean.h>
23 #include <isc/assertions.h>
24 
25 #ifdef ISC_LIST_CHECKINIT
26 #define ISC_LINK_INSIST(x) ISC_INSIST(x)
27 #else
28 #define ISC_LINK_INSIST(x)
29 #endif
30 
31 #define ISC_LIST(type) struct { type *head, *tail; }
32 #define ISC_LIST_INIT(list) \
33 	do { (list).head = NULL; (list).tail = NULL; } while (0)
34 
35 #define ISC_LINK(type) struct { type *prev, *next; }
36 #define ISC_LINK_INIT_TYPE(elt, link, type) \
37 	do { \
38 		(elt)->link.prev = (type *)(-1); \
39 		(elt)->link.next = (type *)(-1); \
40 	} while (0)
41 #define ISC_LINK_INIT(elt, link) \
42 	ISC_LINK_INIT_TYPE(elt, link, void)
43 #define ISC_LINK_LINKED(elt, link) ((void *)((elt)->link.prev) != (void *)(-1))
44 
45 #define ISC_LIST_HEAD(list) ((list).head)
46 #define ISC_LIST_TAIL(list) ((list).tail)
47 #define ISC_LIST_EMPTY(list) ISC_TF((list).head == NULL)
48 
49 #define __ISC_LIST_PREPENDUNSAFE(list, elt, link) \
50 	do { \
51 		if ((list).head != NULL) \
52 			(list).head->link.prev = (elt); \
53 		else \
54 			(list).tail = (elt); \
55 		(elt)->link.prev = NULL; \
56 		(elt)->link.next = (list).head; \
57 		(list).head = (elt); \
58 	} while (0)
59 
60 #define ISC_LIST_PREPEND(list, elt, link) \
61 	do { \
62 		ISC_LINK_INSIST(!ISC_LINK_LINKED(elt, link)); \
63 		__ISC_LIST_PREPENDUNSAFE(list, elt, link); \
64 	} while (0)
65 
66 #define ISC_LIST_INITANDPREPEND(list, elt, link) \
67 		__ISC_LIST_PREPENDUNSAFE(list, elt, link)
68 
69 #define __ISC_LIST_APPENDUNSAFE(list, elt, link) \
70 	do { \
71 		if ((list).tail != NULL) \
72 			(list).tail->link.next = (elt); \
73 		else \
74 			(list).head = (elt); \
75 		(elt)->link.prev = (list).tail; \
76 		(elt)->link.next = NULL; \
77 		(list).tail = (elt); \
78 	} while (0)
79 
80 #define ISC_LIST_APPEND(list, elt, link) \
81 	do { \
82 		ISC_LINK_INSIST(!ISC_LINK_LINKED(elt, link)); \
83 		__ISC_LIST_APPENDUNSAFE(list, elt, link); \
84 	} while (0)
85 
86 #define ISC_LIST_INITANDAPPEND(list, elt, link) \
87 		__ISC_LIST_APPENDUNSAFE(list, elt, link)
88 
89 #define __ISC_LIST_UNLINKUNSAFE_TYPE(list, elt, link, type) \
90 	do { \
91 		if ((elt)->link.next != NULL) \
92 			(elt)->link.next->link.prev = (elt)->link.prev; \
93 		else \
94 			(list).tail = (elt)->link.prev; \
95 		if ((elt)->link.prev != NULL) \
96 			(elt)->link.prev->link.next = (elt)->link.next; \
97 		else \
98 			(list).head = (elt)->link.next; \
99 		(elt)->link.prev = (type *)(-1); \
100 		(elt)->link.next = (type *)(-1); \
101 	} while (0)
102 
103 #define __ISC_LIST_UNLINKUNSAFE(list, elt, link) \
104 	__ISC_LIST_UNLINKUNSAFE_TYPE(list, elt, link, void)
105 
106 #define ISC_LIST_UNLINK_TYPE(list, elt, link, type) \
107 	do { \
108 		ISC_LINK_INSIST(ISC_LINK_LINKED(elt, link)); \
109 		__ISC_LIST_UNLINKUNSAFE_TYPE(list, elt, link, type); \
110 	} while (0)
111 #define ISC_LIST_UNLINK(list, elt, link) \
112 	ISC_LIST_UNLINK_TYPE(list, elt, link, void)
113 
114 #define ISC_LIST_PREV(elt, link) ((elt)->link.prev)
115 #define ISC_LIST_NEXT(elt, link) ((elt)->link.next)
116 
117 #define __ISC_LIST_INSERTBEFOREUNSAFE(list, before, elt, link) \
118 	do { \
119 		if ((before)->link.prev == NULL) \
120 			ISC_LIST_PREPEND(list, elt, link); \
121 		else { \
122 			(elt)->link.prev = (before)->link.prev; \
123 			(before)->link.prev = (elt); \
124 			(elt)->link.prev->link.next = (elt); \
125 			(elt)->link.next = (before); \
126 		} \
127 	} while (0)
128 
129 #define ISC_LIST_INSERTBEFORE(list, before, elt, link) \
130 	do { \
131 		ISC_LINK_INSIST(ISC_LINK_LINKED(before, link)); \
132 		ISC_LINK_INSIST(!ISC_LINK_LINKED(elt, link)); \
133 		__ISC_LIST_INSERTBEFOREUNSAFE(list, before, elt, link); \
134 	} while (0)
135 
136 #define __ISC_LIST_INSERTAFTERUNSAFE(list, after, elt, link) \
137 	do { \
138 		if ((after)->link.next == NULL) \
139 			ISC_LIST_APPEND(list, elt, link); \
140 		else { \
141 			(elt)->link.next = (after)->link.next; \
142 			(after)->link.next = (elt); \
143 			(elt)->link.next->link.prev = (elt); \
144 			(elt)->link.prev = (after); \
145 		} \
146 	} while (0)
147 
148 #define ISC_LIST_INSERTAFTER(list, after, elt, link) \
149 	do { \
150 		ISC_LINK_INSIST(ISC_LINK_LINKED(after, link)); \
151 		ISC_LINK_INSIST(!ISC_LINK_LINKED(elt, link)); \
152 		__ISC_LIST_INSERTAFTERUNSAFE(list, after, elt, link); \
153 	} while (0)
154 
155 #define ISC_LIST_APPENDLIST(list1, list2, link) \
156 	do { \
157 		if (ISC_LIST_EMPTY(list1)) \
158 			(list1) = (list2); \
159 		else if (!ISC_LIST_EMPTY(list2)) { \
160 			(list1).tail->link.next = (list2).head; \
161 			(list2).head->link.prev = (list1).tail; \
162 			(list1).tail = (list2).tail; \
163 		} \
164 		(list2).head = NULL; \
165 		(list2).tail = NULL; \
166 	} while (0)
167 
168 #define ISC_LIST_ENQUEUE(list, elt, link) ISC_LIST_APPEND(list, elt, link)
169 #define __ISC_LIST_ENQUEUEUNSAFE(list, elt, link) \
170 	__ISC_LIST_APPENDUNSAFE(list, elt, link)
171 #define ISC_LIST_DEQUEUE(list, elt, link) \
172 	 ISC_LIST_UNLINK_TYPE(list, elt, link, void)
173 #define ISC_LIST_DEQUEUE_TYPE(list, elt, link, type) \
174 	 ISC_LIST_UNLINK_TYPE(list, elt, link, type)
175 #define __ISC_LIST_DEQUEUEUNSAFE(list, elt, link) \
176 	__ISC_LIST_UNLINKUNSAFE_TYPE(list, elt, link, void)
177 #define __ISC_LIST_DEQUEUEUNSAFE_TYPE(list, elt, link, type) \
178 	__ISC_LIST_UNLINKUNSAFE_TYPE(list, elt, link, type)
179 
180 #endif /* ISC_LIST_H */
181