1 /* active_list.h - the opkg package management system
3 Tick Chen <tick@openmoko.com>
5 Copyright (C) 2008 Openmoko Inc.
7 This program is free software; you can redistribute it and/or
8 modify it under the terms of the GNU General Public License as
9 published by the Free Software Foundation; either version 2, or (at
10 your option) any later version.
12 This program is distributed in the hope that it will be useful, but
13 WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 General Public License for more details.
19 #include "active_list.h"
24 #include "libbb/libbb.h"
26 void active_list_init(struct active_list *ptr) {
27 INIT_LIST_HEAD(&ptr->node);
28 INIT_LIST_HEAD(&ptr->depend);
34 struct active_list * active_list_next(struct active_list *head, struct active_list *ptr) {
35 struct active_list *next=NULL;
37 fprintf(stderr, "active_list_next head = %p, ptr = %p invalid value!!\n", head, ptr);
42 next = list_entry(ptr->node.next, struct active_list, node);
46 if ( ptr->depended && &ptr->depended->depend == ptr->node.next ) {
49 while ( next->depend.next != &next->depend ) {
50 next = list_entry(next->depend.next, struct active_list, node);
56 struct active_list * active_list_prev(struct active_list *head, struct active_list *ptr) {
57 struct active_list *prev=NULL;
59 fprintf(stderr, "active_list_prev head = %p, ptr = %p invalid value!!\n", head, ptr);
64 if ( ptr->depend.prev != &ptr->depend ) {
65 prev = list_entry(ptr->depend.prev, struct active_list, node);
68 if ( ptr->depended && ptr->depended != head && &ptr->depended->depend == ptr->node.prev ) {
69 prev = list_entry(ptr->depended->node.prev, struct active_list, node);
71 prev = list_entry(ptr->node.prev, struct active_list, node);
78 struct active_list *active_list_move_node(struct active_list *old_head, struct active_list *new_head, struct active_list *node) {
79 struct active_list *prev;
80 if (!old_head || !new_head || !node)
82 if (old_head == new_head)
84 prev = active_list_prev(old_head, node);
85 active_list_add(new_head, node);
89 static void list_head_clear (struct list_head *head) {
90 struct active_list *next;
91 struct list_head *n, *ptr;
94 list_for_each_safe(ptr, n , head) {
95 next = list_entry(ptr, struct active_list, node);
96 if (next->depend.next != &next->depend) {
97 list_head_clear(&next->depend);
99 active_list_init(next);
102 void active_list_clear(struct active_list *head) {
103 list_head_clear(&head->node);
104 if (head->depend.next != &head->depend) {
105 list_head_clear(&head->depend);
107 active_list_init(head);
110 void active_list_add_depend(struct active_list *node, struct active_list *depend) {
111 list_del_init(&depend->node);
112 list_add_tail(&depend->node, &node->depend);
113 depend->depended = node;
116 void active_list_add(struct active_list *head, struct active_list *node) {
117 list_del_init(&node->node);
118 list_add_tail(&node->node, &head->node);
119 node->depended = head;
122 struct active_list * active_list_head_new() {
123 struct active_list * head = xcalloc(1, sizeof(struct active_list));
124 active_list_init(head);
128 void active_list_head_delete(struct active_list *head) {
129 active_list_clear(head);
135 * Note. the list should not be large, or it will be very inefficient.
138 struct active_list * active_list_sort(struct active_list *head, int (*compare)(const void *, const void *)) {
139 struct active_list tmphead;
140 struct active_list *node, *ptr;
143 active_list_init(&tmphead);
144 for (node = active_list_next(head, NULL); node; node = active_list_next(head, NULL)) {
145 if (tmphead.node.next == &tmphead.node) {
146 active_list_move_node(head, &tmphead, node);
148 for (ptr = active_list_next(&tmphead, NULL); ptr; ptr=active_list_next(&tmphead, ptr)) {
149 if (compare(ptr, node) <= 0) {
154 active_list_move_node(head, &tmphead, node);
156 active_list_move_node(head, ptr, node);
159 node->depended = &tmphead;
161 for (ptr = active_list_prev(&tmphead, NULL); ptr; ptr=active_list_prev(&tmphead, NULL)) {
162 active_list_move_node(&tmphead, head, ptr);