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-rw-r--r--mysys/list.c116
1 files changed, 116 insertions, 0 deletions
diff --git a/mysys/list.c b/mysys/list.c
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+/* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult AB
+
+ This library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Library General Public
+ License as published by the Free Software Foundation; either
+ version 2 of the License, or (at your option) any later version.
+
+ This library 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
+ Library General Public License for more details.
+
+ You should have received a copy of the GNU Library General Public
+ License along with this library; 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: %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, pbool 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=(LIST*) my_malloc(sizeof(LIST),MYF(MY_FAE));
+ if (!new)
+ return 0;
+ new->data=data;
+ return list_add(list,new);
+}
+
+
+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=rest(list);
+ }
+ return 0;
+}