xref: /trueos/usr.bin/csup/queue.h (revision 834fb25a9ed2240101506d137b5be7d71c75f306)
1 /*-
2  * Copyright (c) 1991, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 4. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  *	@(#)queue.h	8.5 (Berkeley) 8/20/94
30  * $FreeBSD$
31  *
32  * $FreeBSD$
33  */
34 
35 #ifndef _QUEUE_H_
36 #define	_QUEUE_H_
37 
38 #undef __offsetof
39 #define	__offsetof(type, field)	((size_t)(&((type *)0)->field))
40 
41 /*
42  * Singly-linked Tail queue declarations.
43  */
44 #undef STAILQ_HEAD
45 #define	STAILQ_HEAD(name, type)						\
46 struct name {								\
47 	struct type *stqh_first;/* first element */			\
48 	struct type **stqh_last;/* addr of last next element */		\
49 }
50 
51 #undef STAILQ_HEAD_INITIALIZER
52 #define	STAILQ_HEAD_INITIALIZER(head)					\
53 	{ NULL, &(head).stqh_first }
54 
55 #undef STAILQ_ENTRY
56 #define	STAILQ_ENTRY(type)						\
57 struct {								\
58 	struct type *stqe_next;	/* next element */			\
59 }
60 
61 #undef STAILQ_EMPTY
62 #define	STAILQ_EMPTY(head)	((head)->stqh_first == NULL)
63 
64 #undef STAILQ_FIRST
65 #define	STAILQ_FIRST(head)	((head)->stqh_first)
66 
67 #undef STAILQ_FOREACH
68 #define	STAILQ_FOREACH(var, head, field)				\
69 	for((var) = STAILQ_FIRST((head));				\
70 	   (var);							\
71 	   (var) = STAILQ_NEXT((var), field))
72 
73 #undef STAILQ_FOREACH_SAFE
74 #define	STAILQ_FOREACH_SAFE(var, head, field, tvar)			\
75 	for ((var) = STAILQ_FIRST((head));				\
76 	    (var) && ((tvar) = STAILQ_NEXT((var), field), 1);		\
77 	    (var) = (tvar))
78 
79 #undef STAILQ_INIT
80 #define	STAILQ_INIT(head) do {						\
81 	STAILQ_FIRST((head)) = NULL;					\
82 	(head)->stqh_last = &STAILQ_FIRST((head));			\
83 } while (0)
84 
85 #undef STAILQ_INSERT_AFTER
86 #define	STAILQ_INSERT_AFTER(head, tqelm, elm, field) do {		\
87 	if ((STAILQ_NEXT((elm), field) = STAILQ_NEXT((tqelm), field)) == NULL)\
88 		(head)->stqh_last = &STAILQ_NEXT((elm), field);		\
89 	STAILQ_NEXT((tqelm), field) = (elm);				\
90 } while (0)
91 
92 #undef STAILQ_INSERT_HEAD
93 #define	STAILQ_INSERT_HEAD(head, elm, field) do {			\
94 	if ((STAILQ_NEXT((elm), field) = STAILQ_FIRST((head))) == NULL)	\
95 		(head)->stqh_last = &STAILQ_NEXT((elm), field);		\
96 	STAILQ_FIRST((head)) = (elm);					\
97 } while (0)
98 
99 #undef STAILQ_INSERT_TAIL
100 #define	STAILQ_INSERT_TAIL(head, elm, field) do {			\
101 	STAILQ_NEXT((elm), field) = NULL;				\
102 	*(head)->stqh_last = (elm);					\
103 	(head)->stqh_last = &STAILQ_NEXT((elm), field);			\
104 } while (0)
105 
106 #undef STAILQ_LAST
107 #define	STAILQ_LAST(head, type, field)					\
108 	(STAILQ_EMPTY((head)) ?						\
109 		NULL :							\
110 	        ((struct type *)(void *)				\
111 		((char *)((head)->stqh_last) - __offsetof(struct type, field))))
112 
113 #undef STAILQ_NEXT
114 #define	STAILQ_NEXT(elm, field)	((elm)->field.stqe_next)
115 
116 #undef STAILQ_REMOVE
117 #define	STAILQ_REMOVE(head, elm, type, field) do {			\
118 	if (STAILQ_FIRST((head)) == (elm)) {				\
119 		STAILQ_REMOVE_HEAD((head), field);			\
120 	}								\
121 	else {								\
122 		struct type *curelm = STAILQ_FIRST((head));		\
123 		while (STAILQ_NEXT(curelm, field) != (elm))		\
124 			curelm = STAILQ_NEXT(curelm, field);		\
125 		if ((STAILQ_NEXT(curelm, field) =			\
126 		     STAILQ_NEXT(STAILQ_NEXT(curelm, field), field)) == NULL)\
127 			(head)->stqh_last = &STAILQ_NEXT((curelm), field);\
128 	}								\
129 } while (0)
130 
131 #undef STAILQ_REMOVE_HEAD
132 #define	STAILQ_REMOVE_HEAD(head, field) do {				\
133 	if ((STAILQ_FIRST((head)) =					\
134 	     STAILQ_NEXT(STAILQ_FIRST((head)), field)) == NULL)		\
135 		(head)->stqh_last = &STAILQ_FIRST((head));		\
136 } while (0)
137 
138 #undef STAILQ_REMOVE_HEAD_UNTIL
139 #define	STAILQ_REMOVE_HEAD_UNTIL(head, elm, field) do {			\
140 	if ((STAILQ_FIRST((head)) = STAILQ_NEXT((elm), field)) == NULL)	\
141 		(head)->stqh_last = &STAILQ_FIRST((head));		\
142 } while (0)
143 
144 /*
145  * List declarations.
146  */
147 #undef LIST_HEAD
148 #define	LIST_HEAD(name, type)						\
149 struct name {								\
150 	struct type *lh_first;	/* first element */			\
151 }
152 
153 #undef LIST_HEAD_INITIALIZER
154 #define	LIST_HEAD_INITIALIZER(head)					\
155 	{ NULL }
156 
157 #undef LIST_ENTRY
158 #define	LIST_ENTRY(type)						\
159 struct {								\
160 	struct type *le_next;	/* next element */			\
161 	struct type **le_prev;	/* address of previous next element */	\
162 }
163 
164 /*
165  * List functions.
166  */
167 
168 #undef LIST_EMPTY
169 #define	LIST_EMPTY(head)	((head)->lh_first == NULL)
170 
171 #undef LIST_FIRST
172 #define	LIST_FIRST(head)	((head)->lh_first)
173 
174 #undef LIST_FOREACH
175 #define	LIST_FOREACH(var, head, field)					\
176 	for ((var) = LIST_FIRST((head));				\
177 	    (var);							\
178 	    (var) = LIST_NEXT((var), field))
179 
180 #undef LIST_FOREACH_SAFE
181 #define	LIST_FOREACH_SAFE(var, head, field, tvar)			\
182 	for ((var) = LIST_FIRST((head));				\
183 	    (var) && ((tvar) = LIST_NEXT((var), field), 1);		\
184 	    (var) = (tvar))
185 
186 #undef LIST_INIT
187 #define	LIST_INIT(head) do {						\
188 	LIST_FIRST((head)) = NULL;					\
189 } while (0)
190 
191 #undef LIST_INSERT_AFTER
192 #define	LIST_INSERT_AFTER(listelm, elm, field) do {			\
193 	if ((LIST_NEXT((elm), field) = LIST_NEXT((listelm), field)) != NULL)\
194 		LIST_NEXT((listelm), field)->field.le_prev =		\
195 		    &LIST_NEXT((elm), field);				\
196 	LIST_NEXT((listelm), field) = (elm);				\
197 	(elm)->field.le_prev = &LIST_NEXT((listelm), field);		\
198 } while (0)
199 
200 #undef LIST_INSERT_BEFORE
201 #define	LIST_INSERT_BEFORE(listelm, elm, field) do {			\
202 	(elm)->field.le_prev = (listelm)->field.le_prev;		\
203 	LIST_NEXT((elm), field) = (listelm);				\
204 	*(listelm)->field.le_prev = (elm);				\
205 	(listelm)->field.le_prev = &LIST_NEXT((elm), field);		\
206 } while (0)
207 
208 #undef LIST_INSERT_HEAD
209 #define	LIST_INSERT_HEAD(head, elm, field) do {				\
210 	if ((LIST_NEXT((elm), field) = LIST_FIRST((head))) != NULL)	\
211 		LIST_FIRST((head))->field.le_prev = &LIST_NEXT((elm), field);\
212 	LIST_FIRST((head)) = (elm);					\
213 	(elm)->field.le_prev = &LIST_FIRST((head));			\
214 } while (0)
215 
216 #undef LIST_NEXT
217 #define	LIST_NEXT(elm, field)	((elm)->field.le_next)
218 
219 #undef LIST_REMOVE
220 #define	LIST_REMOVE(elm, field) do {					\
221 	if (LIST_NEXT((elm), field) != NULL)				\
222 		LIST_NEXT((elm), field)->field.le_prev = 		\
223 		    (elm)->field.le_prev;				\
224 	*(elm)->field.le_prev = LIST_NEXT((elm), field);		\
225 } while (0)
226 
227 #endif /* !_QUEUE_H_ */
228