/* vim: set ts=4 sw=4 ai:
 * sl.c -- singly linked list implementation derived from NetBSD's queue.h
 */

#include <stdlib.h>
#include "sl.h"

struct slh *sl_new(void)
{
	struct slh *hd;

	hd = malloc(sizeof(*hd));
	if (hd != NULL)
		sl_init(hd);

	return hd;
}

struct sle *sl_elem_new(void *data)
{
	struct sle *e;

	e = malloc(sizeof(*e));
	if (e != NULL)
		e->data = data;

	return e;
}

void sl_insert_after(struct sle *e, struct sle *n)
{
	n->next = e->next;
	e->next = n;
}

void sl_insert_head(struct slh *hd, struct sle *e)
{
	e->next = hd->first;
	hd->first = e;
}

void sl_remove_after(struct sle *e)
{
	if (e->next != NULL)
		e->next = e->next->next;
}

void sl_remove_head(struct slh *hd)
{
	if (hd->first != NULL)
		hd->first = hd->first->next;
}

void sl_remove(struct slh *hd, struct sle *e)
{
	struct sle *cur;

	if (hd->first == e) {
		hd->first = hd->first->next;
	}
	else {
		cur = hd->first;
		while (cur->next != NULL && cur->next != e)
			cur = cur->next;
		if (cur->next == NULL)
			return;
		cur->next = cur->next->next;
	}
}

void sl_cleanup(struct slh *hd, void (*func)(void *))
{
	struct sle *e, *t;

	sl_foreach_safe(e, hd, t) {
		sl_remove(hd, e);
		if (func)
			func(e->data);
		free(e);
	}
}

struct sle *sl_find_from_data(struct slh *hd, const void *data, int (*cmp)(const void *, const void *))
{
	struct sle *e;

	if (hd && !sl_empty(hd))
		sl_foreach(e, hd)
			if (e->data && cmp(e->data, data) == 0)
				return e;

	return NULL;
}