1 /* Authors: Arnaud Legrand */
3 /* This program is free software; you can redistribute it and/or modify it
4 under the terms of the license (GNU LGPL) which comes with this package. */
6 /* Warning, this module is done to be efficient and performs tons of
7 cast and dirty things. So avoid using it unless you really know
10 /* This type should be added to a type that is to be used in such a swag */
12 #include "xbt/sysdep.h"
13 #include "xbt/error.h"
16 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(swag,xbt,"Swag : O(1) set library");
18 #define PREV(obj,offset) xbt_swag_getPrev(obj,offset)
19 #define NEXT(obj,offset) xbt_swag_getNext(obj,offset)
22 Usage : xbt_swag_new(&obj.setA-&obj);
25 xbt_swag_t xbt_swag_new(size_t offset)
27 xbt_swag_t swag = xbt_new0(s_xbt_swag_t, 1);
29 swag->offset = offset;
35 void xbt_swag_free(xbt_swag_t swag)
40 void xbt_swag_init(xbt_swag_t swag, size_t offset)
42 swag->offset = offset;
45 void xbt_swag_insert(void *obj, xbt_swag_t swag)
48 if (xbt_swag_belongs(obj, swag))
52 if (swag->head == NULL) {
58 PREV(obj, swag->offset) = swag->tail;
59 NEXT(PREV(obj, swag->offset), swag->offset) = obj;
64 void *xbt_swag_remove(void *obj, xbt_swag_t swag)
66 size_t offset = swag->offset;
68 if ((!obj) || (!swag))
70 if(!xbt_swag_belongs(obj, swag)) /* Trying to remove an object that
71 was not in this swag */
74 if (swag->head == swag->tail) { /* special case */
75 if (swag->head != obj) /* Trying to remove an object that was not in this swag */
79 } else if (obj == swag->head) { /* It's the head */
80 swag->head = NEXT(obj, offset);
81 PREV(swag->head, offset) = NULL;
82 NEXT(obj, offset) = NULL;
83 } else if (obj == swag->tail) { /* It's the tail */
84 swag->tail = PREV(obj, offset);
85 NEXT(swag->tail, offset) = NULL;
86 PREV(obj, offset) = NULL;
87 } else { /* It's in the middle */
88 NEXT(PREV(obj, offset), offset) = NEXT(obj, offset);
89 PREV(NEXT(obj, offset), offset) = PREV(obj, offset);
90 PREV(obj, offset) = NEXT(obj, offset) = NULL;
96 void *xbt_swag_extract(xbt_swag_t swag)
98 size_t offset = swag->offset;
101 if ((!swag) || (!(swag->head)))
106 if (swag->head == swag->tail) { /* special case */
107 swag->head = swag->tail = NULL;
109 swag->head = NEXT(obj, offset);
110 PREV(swag->head, offset) = NULL;
111 NEXT(obj, offset) = NULL;
117 int xbt_swag_size(xbt_swag_t swag)
119 return (swag->count);
122 int xbt_swag_belongs(void *obj, xbt_swag_t swag)
124 return ((NEXT(obj, swag->offset)) || (PREV(obj, swag->offset))
125 || (swag->head == obj));