list.c
上传用户:romrleung
上传日期:2022-05-23
资源大小:18897k
文件大小:2k
- /* Copyright (C) 2000 MySQL AB
- This program is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
- (at your option) any later version.
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
- You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
- /*
- Code for handling dubble-linked lists in C
- */
- #include "mysys_priv.h"
- #include <my_list.h>
- /* Add a element to start of list */
- LIST *list_add(LIST *root, LIST *element)
- {
- DBUG_ENTER("list_add");
- DBUG_PRINT("enter",("root: 0x%lx element: %lx", root, element));
- if (root)
- {
- if (root->prev) /* If add in mid of list */
- root->prev->next= element;
- element->prev=root->prev;
- root->prev=element;
- }
- else
- element->prev=0;
- element->next=root;
- DBUG_RETURN(element); /* New root */
- }
- LIST *list_delete(LIST *root, LIST *element)
- {
- if (element->prev)
- element->prev->next=element->next;
- else
- root=element->next;
- if (element->next)
- element->next->prev=element->prev;
- return root;
- }
- void list_free(LIST *root, uint free_data)
- {
- LIST *next;
- while (root)
- {
- next=root->next;
- if (free_data)
- my_free((gptr) root->data,MYF(0));
- my_free((gptr) root,MYF(0));
- root=next;
- }
- }
- LIST *list_cons(void *data, LIST *list)
- {
- LIST *new_charset=(LIST*) my_malloc(sizeof(LIST),MYF(MY_FAE));
- if (!new_charset)
- return 0;
- new_charset->data=data;
- return list_add(list,new_charset);
- }
- LIST *list_reverse(LIST *root)
- {
- LIST *last;
- last=root;
- while (root)
- {
- last=root;
- root=root->next;
- last->next=last->prev;
- last->prev=root;
- }
- return last;
- }
- uint list_length(LIST *list)
- {
- uint count;
- for (count=0 ; list ; list=list->next, count++) ;
- return count;
- }
- int list_walk(LIST *list, list_walk_action action, gptr argument)
- {
- int error=0;
- while (list)
- {
- if ((error = (*action)(list->data,argument)))
- return error;
- list=list_rest(list);
- }
- return 0;
- }