X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=libbb%2Fllist.c;h=8a74832ee3ff54e50d08c4e86f0c1daefbf0965e;hb=966ec7c067d7a2df5232a69c8d3d2e777347a62d;hp=cb87176c5292bfa379479ae6298cc96c7beff33b;hpb=bee9eb1a9d04503d58070bd1946cc2c0538fcf95;p=oweals%2Fbusybox.git diff --git a/libbb/llist.c b/libbb/llist.c index cb87176c5..8a74832ee 100644 --- a/libbb/llist.c +++ b/libbb/llist.c @@ -1,43 +1,78 @@ +/* vi: set sw=4 ts=4: */ +/* + * linked list helper functions. + * + * Copyright (C) 2003 Glenn McGrath + * Copyright (C) 2005 Vladimir Oleynik + * Copyright (C) 2005 Bernhard Fischer + * Copyright (C) 2006 Rob Landley + * + * Licensed under the GPL v2 or later, see the file LICENSE in this tarball. + */ + #include -#include -#include "unarchive.h" #include "libbb.h" -#ifdef L_llist_add_to -extern llist_t *llist_add_to(llist_t *old_head, char *new_item) +/* Add data to the start of the linked list. */ +void llist_add_to(llist_t **old_head, void *data) { - llist_t *new_head; - - new_head = xmalloc(sizeof(llist_t)); - new_head->data = new_item; - new_head->link = old_head; - - return (new_head); + llist_t *new_head = xmalloc(sizeof(llist_t)); + new_head->data = data; + new_head->link = *old_head; + *old_head = new_head; } -#endif -#ifdef L_llist_add_to_end -extern llist_t *llist_add_to_end(llist_t *list_head, char *data) +/* Add data to the end of the linked list. */ +void llist_add_to_end(llist_t **list_head, void *data) { - llist_t *new_item, *tmp, *prev; - - new_item = xmalloc(sizeof(llist_t)); + llist_t *new_item = xmalloc(sizeof(llist_t)); new_item->data = data; new_item->link = NULL; - prev = NULL; - tmp = list_head; - while (tmp) { - prev = tmp; - tmp = tmp->link; + if (!*list_head) *list_head = new_item; + else { + llist_t *tail = *list_head; + while (tail->link) tail = tail->link; + tail->link = new_item; } - if (prev) { - prev->link = new_item; - } else { - list_head = new_item; +} + +/* Remove first element from the list and return it */ +void *llist_pop(llist_t **head) +{ + void *data; + + if(!*head) data = *head; + else { + void *next = (*head)->link; + data = (*head)->data; + free(*head); + *head = next; } - return (list_head); + return data; } -#endif +/* Recursively free all elements in the linked list. If freeit != NULL + * call it on each datum in the list */ +void llist_free(llist_t *elm, void (*freeit)(void *data)) +{ + while (elm) { + void *data = llist_pop(&elm); + if (freeit) freeit(data); + } +} + +/* Reverse list order. Useful since getopt32 saves option params + * in reverse order */ +llist_t* rev_llist(llist_t *list) +{ + llist_t *new = NULL; + while (list) { + llist_t *next = list->link; + list->link = new; + new = list; + list = next; + } + return new; +}