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
13int 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
46void 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
53static 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
90struct rb_node *rblist__find(struct rblist *rblist, const void *entry)
91{
92	return __rblist__findnew(rblist, entry, false);
93}
94
95struct rb_node *rblist__findnew(struct rblist *rblist, const void *entry)
96{
97	return __rblist__findnew(rblist, entry, true);
98}
99
100void 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
110void 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
121void rblist__delete(struct rblist *rblist)
122{
123	if (rblist != NULL) {
124		rblist__exit(rblist);
125		free(rblist);
126	}
127}
128
129struct 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