1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Based on strlist.c by:
4 * (c) 2009 Arnaldo Carvalho de Melo <acme@redhat.com>
5 */
6
7 #include <errno.h>
8 #include <stdio.h>
9 #include <stdlib.h>
10
11 #include "rblist.h"
12
13 int rblist__add_node(struct rblist *rblist, const void *new_entry)
14 {
15 struct rb_node **p = &rblist->entries.rb_root.rb_node;
16 struct rb_node *parent = NULL, *new_node;
17 bool leftmost = true;
18
19 while (*p != NULL) {
20 int rc;
21
22 parent = *p;
23
24 rc = rblist->node_cmp(parent, new_entry);
25 if (rc > 0)
26 p = &(*p)->rb_left;
27 else if (rc < 0) {
28 p = &(*p)->rb_right;
29 leftmost = false;
30 }
31 else
32 return -EEXIST;
33 }
34
35 new_node = rblist->node_new(rblist, new_entry);
36 if (new_node == NULL)
37 return -ENOMEM;
38
39 rb_link_node(new_node, parent, p);
40 rb_insert_color_cached(new_node, &rblist->entries, leftmost);
41 ++rblist->nr_entries;
42
43 return 0;
44 }
45
46 void rblist__remove_node(struct rblist *rblist, struct rb_node *rb_node)
47 {
48 rb_erase_cached(rb_node, &rblist->entries);
49 --rblist->nr_entries;
50 rblist->node_delete(rblist, rb_node);
51 }
52
53 static struct rb_node *__rblist__findnew(struct rblist *rblist,
54 const void *entry,
55 bool create)
56 {
57 struct rb_node **p = &rblist->entries.rb_root.rb_node;
58 struct rb_node *parent = NULL, *new_node = NULL;
59 bool leftmost = true;
60
61 while (*p != NULL) {
62 int rc;
63
64 parent = *p;
65
66 rc = rblist->node_cmp(parent, entry);
67 if (rc > 0)
68 p = &(*p)->rb_left;
69 else if (rc < 0) {
70 p = &(*p)->rb_right;
71 leftmost = false;
72 }
73 else
74 return parent;
75 }
76
77 if (create) {
78 new_node = rblist->node_new(rblist, entry);
79 if (new_node) {
80 rb_link_node(new_node, parent, p);
81 rb_insert_color_cached(new_node,
82 &rblist->entries, leftmost);
83 ++rblist->nr_entries;
84 }
85 }
86
87 return new_node;
88 }
89
90 struct rb_node *rblist__find(struct rblist *rblist, const void *entry)
91 {
92 return __rblist__findnew(rblist, entry, false);
93 }
94
95 struct rb_node *rblist__findnew(struct rblist *rblist, const void *entry)
96 {
97 return __rblist__findnew(rblist, entry, true);
98 }
99
100 void rblist__init(struct rblist *rblist)
101 {
102 if (rblist != NULL) {
103 rblist->entries = RB_ROOT_CACHED;
104 rblist->nr_entries = 0;
105 }
106
107 return;
108 }
109
110 void rblist__exit(struct rblist *rblist)
111 {
112 struct rb_node *pos, *next = rb_first_cached(&rblist->entries);
113
114 while (next) {
115 pos = next;
116 next = rb_next(pos);
117 rblist__remove_node(rblist, pos);
118 }
119 }
120
121 void rblist__delete(struct rblist *rblist)
122 {
123 if (rblist != NULL) {
124 rblist__exit(rblist);
125 free(rblist);
126 }
127 }
128
129 struct rb_node *rblist__entry(const struct rblist *rblist, unsigned int idx)
130 {
131 struct rb_node *node;
132
133 for (node = rb_first_cached(&rblist->entries); node;
134 node = rb_next(node)) {
135 if (!idx--)
136 return node;
137 }
138
139 return NULL;
140 }
141
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.