hush/libbb/llist.c
Denis Vlasenko 1265df1f31 libbb: shrink linked list ops (by xmaks AT email.cz)
function                                             old     new   delta
llist_pop                                             33      29      -4
llist_unlink                                          47      28     -19
llist_add_to_end                                      50      31     -19
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 0/3 up/down: 0/-42)             Total: -42 bytes
2009-01-13 15:22:50 +00:00

89 lines
1.8 KiB
C

/* vi: set sw=4 ts=4: */
/*
* linked list helper functions.
*
* Copyright (C) 2003 Glenn McGrath
* Copyright (C) 2005 Vladimir Oleynik
* Copyright (C) 2005 Bernhard Reutner-Fischer
* Copyright (C) 2006 Rob Landley <rob@landley.net>
*
* Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
*/
#include "libbb.h"
/* Add data to the start of the linked list. */
void FAST_FUNC llist_add_to(llist_t **old_head, void *data)
{
llist_t *new_head = xmalloc(sizeof(llist_t));
new_head->data = data;
new_head->link = *old_head;
*old_head = new_head;
}
/* Add data to the end of the linked list. */
void FAST_FUNC llist_add_to_end(llist_t **list_head, void *data)
{
while (*list_head)
list_head = &(*list_head)->link;
*list_head = xzalloc(sizeof(llist_t));
(*list_head)->data = data;
/*(*list_head)->link = NULL;*/
}
/* Remove first element from the list and return it */
void* FAST_FUNC llist_pop(llist_t **head)
{
void *data = NULL;
llist_t *temp = *head;
if (temp) {
data = temp->data;
*head = temp->link;
free(temp);
}
return data;
}
/* Unlink arbitrary given element from the list */
void FAST_FUNC llist_unlink(llist_t **head, llist_t *elm)
{
if (!elm)
return;
while (*head) {
if (*head == elm) {
*head = (*head)->link;
break;
}
head = &(*head)->link;
}
}
/* Recursively free all elements in the linked list. If freeit != NULL
* call it on each datum in the list */
void FAST_FUNC llist_free(llist_t *elm, void (*freeit) (void *data))
{
while (elm) {
void *data = llist_pop(&elm);
if (freeit)
freeit(data);
}
}
/* Reverse list order. */
llist_t* FAST_FUNC llist_rev(llist_t *list)
{
llist_t *rev = NULL;
while (list) {
llist_t *next = list->link;
list->link = rev;
rev = list;
list = next;
}
return rev;
}