1/* Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.
2
3 This program is free software; you can redistribute it and/or modify
4 it under the terms of the GNU General Public License as published by
5 the Free Software Foundation; version 2 of the License.
6
7 This program is distributed in the hope that it will be useful,
8 but WITHOUT ANY WARRANTY; without even the implied warranty of
9 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
10 GNU General Public License for more details.
11
12 You should have received a copy of the GNU General Public License
13 along with this program; if not, write to the Free Software
14 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */
15
16/*
17 Code for handling dubble-linked lists in C
18*/
19
20#include "mysys_priv.h"
21#include <my_list.h>
22
23
24
25 /* Add a element to start of list */
26
27LIST *list_add(LIST *root, LIST *element)
28{
29 DBUG_ENTER("list_add");
30 DBUG_PRINT("enter",("root: %p element: %p", root, element));
31 if (root)
32 {
33 if (root->prev) /* If add in mid of list */
34 root->prev->next= element;
35 element->prev=root->prev;
36 root->prev=element;
37 }
38 else
39 element->prev=0;
40 element->next=root;
41 DBUG_RETURN(element); /* New root */
42}
43
44
45LIST *list_delete(LIST *root, LIST *element)
46{
47 if (element->prev)
48 element->prev->next=element->next;
49 else
50 root=element->next;
51 if (element->next)
52 element->next->prev=element->prev;
53 return root;
54}
55
56
57void list_free(LIST *root, uint free_data)
58{
59 LIST *next;
60 while (root)
61 {
62 next=root->next;
63 if (free_data)
64 my_free(root->data);
65 my_free(root);
66 root=next;
67 }
68}
69
70
71LIST *list_cons(void *data, LIST *list)
72{
73 LIST *new_charset=(LIST*) my_malloc(sizeof(LIST),MYF(MY_FAE));
74 if (!new_charset)
75 return 0;
76 new_charset->data=data;
77 return list_add(list,new_charset);
78}
79
80
81LIST *list_reverse(LIST *root)
82{
83 LIST *last;
84
85 last=root;
86 while (root)
87 {
88 last=root;
89 root=root->next;
90 last->next=last->prev;
91 last->prev=root;
92 }
93 return last;
94}
95
96uint list_length(LIST *list)
97{
98 uint count;
99 for (count=0 ; list ; list=list->next, count++) ;
100 return count;
101}
102
103
104int list_walk(LIST *list, list_walk_action action, uchar* argument)
105{
106 int error=0;
107 while (list)
108 {
109 if ((error = (*action)(list->data,argument)))
110 return error;
111 list=list_rest(list);
112 }
113 return 0;
114}
115