summaryrefslogtreecommitdiffstats
path: root/nsprpub/pr/include/prclist.h
blob: a069176055692e83d5919a1fcfb45c5e561cdc42 (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
/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef prclist_h___
#define prclist_h___

#include "prtypes.h"

typedef struct PRCListStr PRCList;

/*
** Circular linked list
*/
struct PRCListStr {
    PRCList *next;
    PRCList *prev;
};

/*
** Insert element "_e" into the list, before "_l".
*/
#define PR_INSERT_BEFORE(_e,_l)  \
    PR_BEGIN_MACRO       \
    (_e)->next = (_l);   \
    (_e)->prev = (_l)->prev; \
    (_l)->prev->next = (_e); \
    (_l)->prev = (_e);   \
    PR_END_MACRO

/*
** Insert element "_e" into the list, after "_l".
*/
#define PR_INSERT_AFTER(_e,_l)   \
    PR_BEGIN_MACRO       \
    (_e)->next = (_l)->next; \
    (_e)->prev = (_l);   \
    (_l)->next->prev = (_e); \
    (_l)->next = (_e);   \
    PR_END_MACRO

/*
** Return the element following element "_e"
*/
#define PR_NEXT_LINK(_e)     \
        ((_e)->next)
/*
** Return the element preceding element "_e"
*/
#define PR_PREV_LINK(_e)     \
        ((_e)->prev)

/*
** Append an element "_e" to the end of the list "_l"
*/
#define PR_APPEND_LINK(_e,_l) PR_INSERT_BEFORE(_e,_l)

/*
** Insert an element "_e" at the head of the list "_l"
*/
#define PR_INSERT_LINK(_e,_l) PR_INSERT_AFTER(_e,_l)

/* Return the head/tail of the list */
#define PR_LIST_HEAD(_l) (_l)->next
#define PR_LIST_TAIL(_l) (_l)->prev

/*
** Remove the element "_e" from it's circular list.
*/
#define PR_REMOVE_LINK(_e)         \
    PR_BEGIN_MACRO             \
    (_e)->prev->next = (_e)->next; \
    (_e)->next->prev = (_e)->prev; \
    PR_END_MACRO

/*
** Remove the element "_e" from it's circular list. Also initializes the
** linkage.
*/
#define PR_REMOVE_AND_INIT_LINK(_e)    \
    PR_BEGIN_MACRO             \
    (_e)->prev->next = (_e)->next; \
    (_e)->next->prev = (_e)->prev; \
    (_e)->next = (_e);         \
    (_e)->prev = (_e);         \
    PR_END_MACRO

/*
** Return non-zero if the given circular list "_l" is empty, zero if the
** circular list is not empty
*/
#define PR_CLIST_IS_EMPTY(_l) \
    ((_l)->next == (_l))

/*
** Initialize a circular list
*/
#define PR_INIT_CLIST(_l)  \
    PR_BEGIN_MACRO     \
    (_l)->next = (_l); \
    (_l)->prev = (_l); \
    PR_END_MACRO

#define PR_INIT_STATIC_CLIST(_l) \
    {(_l), (_l)}

#endif /* prclist_h___ */