source: MondoRescue/branches/3.2/mindi-busybox/libbb/llist.c@ 3232

/* 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 GPLv2 or later, see file LICENSE in this source tree.
 */

#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;
}

llist_t* FAST_FUNC llist_find_str(llist_t *list, const char *str)
{
    while (list) {
        if (strcmp(list->data, str) == 0)
            break;
        list = list->link;
    }
    return list;
}