1 /*
2 * Based on strlist.c by:
3 * (c) 2009 Arnaldo Carvalho de Melo <acme@redhat.com>
4 *
5 * Licensed under the GPLv2.
6 */
7
8 #include <errno.h>
9 #include <stdio.h>
10 #include <stdlib.h>
11
12 #include "rblist.h"
13
rblist__add_node(struct rblist * rblist,const void * new_entry)14 int rblist__add_node(struct rblist *rblist, const void *new_entry)
15 {
16 struct rb_node **p = &rblist->entries.rb_node;
17 struct rb_node *parent = NULL, *new_node;
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 else
30 return -EEXIST;
31 }
32
33 new_node = rblist->node_new(rblist, new_entry);
34 if (new_node == NULL)
35 return -ENOMEM;
36
37 rb_link_node(new_node, parent, p);
38 rb_insert_color(new_node, &rblist->entries);
39 ++rblist->nr_entries;
40
41 return 0;
42 }
43
rblist__remove_node(struct rblist * rblist,struct rb_node * rb_node)44 void rblist__remove_node(struct rblist *rblist, struct rb_node *rb_node)
45 {
46 rb_erase(rb_node, &rblist->entries);
47 --rblist->nr_entries;
48 rblist->node_delete(rblist, rb_node);
49 }
50
__rblist__findnew(struct rblist * rblist,const void * entry,bool create)51 static struct rb_node *__rblist__findnew(struct rblist *rblist,
52 const void *entry,
53 bool create)
54 {
55 struct rb_node **p = &rblist->entries.rb_node;
56 struct rb_node *parent = NULL, *new_node = NULL;
57
58 while (*p != NULL) {
59 int rc;
60
61 parent = *p;
62
63 rc = rblist->node_cmp(parent, entry);
64 if (rc > 0)
65 p = &(*p)->rb_left;
66 else if (rc < 0)
67 p = &(*p)->rb_right;
68 else
69 return parent;
70 }
71
72 if (create) {
73 new_node = rblist->node_new(rblist, entry);
74 if (new_node) {
75 rb_link_node(new_node, parent, p);
76 rb_insert_color(new_node, &rblist->entries);
77 ++rblist->nr_entries;
78 }
79 }
80
81 return new_node;
82 }
83
rblist__find(struct rblist * rblist,const void * entry)84 struct rb_node *rblist__find(struct rblist *rblist, const void *entry)
85 {
86 return __rblist__findnew(rblist, entry, false);
87 }
88
rblist__findnew(struct rblist * rblist,const void * entry)89 struct rb_node *rblist__findnew(struct rblist *rblist, const void *entry)
90 {
91 return __rblist__findnew(rblist, entry, true);
92 }
93
rblist__init(struct rblist * rblist)94 void rblist__init(struct rblist *rblist)
95 {
96 if (rblist != NULL) {
97 rblist->entries = RB_ROOT;
98 rblist->nr_entries = 0;
99 }
100
101 return;
102 }
103
rblist__delete(struct rblist * rblist)104 void rblist__delete(struct rblist *rblist)
105 {
106 if (rblist != NULL) {
107 struct rb_node *pos, *next = rb_first(&rblist->entries);
108
109 while (next) {
110 pos = next;
111 next = rb_next(pos);
112 rblist__remove_node(rblist, pos);
113 }
114 free(rblist);
115 }
116 }
117
rblist__entry(const struct rblist * rblist,unsigned int idx)118 struct rb_node *rblist__entry(const struct rblist *rblist, unsigned int idx)
119 {
120 struct rb_node *node;
121
122 for (node = rb_first(&rblist->entries); node; node = rb_next(node)) {
123 if (!idx--)
124 return node;
125 }
126
127 return NULL;
128 }
129