embox

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/**
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 * @file
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 * @brief Implementation of methods in util/tree.h
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 *
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 * @date Oct 8, 2011
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 * @author Avdyukhin Dmitry
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 */
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#include <assert.h>
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#include <stddef.h>
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#include <lib/libds/dlist.h>
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#include <lib/libds/tree.h>
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struct tree_link *tree_children_begin(struct tree_link *tree) {
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	struct dlist_head *lnk;
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	if (NULL == (lnk = (dlist_first_or_null(&tree->children)))) {
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		return NULL;
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	}
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	return dlist_entry(lnk, struct tree_link, list_link);
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}
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struct tree_link *tree_children_end(struct tree_link *tree) {
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	struct dlist_head *lnk;
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	if (dlist_empty(&tree->children)) {
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		return NULL;
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	}
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	lnk = dlist_prev(&tree->children);
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	return dlist_entry(lnk->next, struct tree_link, list_link);
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}
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struct tree_link *tree_children_next(struct tree_link *tree) {
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	return dlist_entry(tree->list_link.next, struct tree_link, list_link);
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}
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struct tree_link *tree_children_prev(struct tree_link *tree) {
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	return dlist_entry(tree->list_link.next, struct tree_link, list_link);
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}
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