gr-fosphor/lib/fosphor/llist.h

82 lines
2.0 KiB
C

/*
* llist.h
*
* Simple double-linked list. Interface similar to the linux kernel
* one, but heavily simplified and rewritten to compile on other compilers
* than GCC.
*
* Copyright (C) 2013-2021 Sylvain Munaut
* SPDX-License-Identifier: GPL-3.0-or-later
*/
#pragma once
/*! \defgroup llist
* @{
*/
/*! \file llist.h
* \brief Simple double-linked list
*/
#include <stddef.h>
struct llist_head {
struct llist_head *next, *prev;
};
#define LLIST_HEAD_INIT(name) { &(name), &(name) }
#define LLIST_HEAD(name) \
struct llist_head name = LLIST_HEAD_INIT(name)
/**
* \brief Add a new entry after the specified head
* \param[in] new new entry to be added
* \param[in] head llist head to add it after
*/
static inline void llist_add(struct llist_head *_new, struct llist_head *head)
{
head->next->prev = _new;
_new->next = head->next;
_new->prev = head;
head->next = _new;
}
/**
* \brief Deletes entry from llist
* \param[in] entry the element to delete from the llist
*/
static inline void llist_del(struct llist_head *entry)
{
entry->next->prev = entry->prev;
entry->prev->next = entry->next;
entry->next = (struct llist_head *)0;
entry->prev = (struct llist_head *)0;
}
/**
* \brief Get the struct for this entry
* \param[in] ptr the &struct llist_head pointer
* \param[in] type the type of the struct this is embedded in
* \param[in] member the name of the llist_struct within the struct
* \returns The struct for this entry
*/
#define llist_entry(ptr, type, member) \
((type *)( (char *)(ptr) - offsetof(type, member) ))
/**
* \brief Iterate over llist of given type
* \param[in] type the type of the loop counter
* \param[out] pos the type * to use as a loop counter
* \param[in] head the head for your llist
* \param[in] member the name of the llist_struct within the struct
*/
#define llist_for_each_entry(type, pos, head, member) \
for (pos = llist_entry((head)->next, type, member); \
&pos->member != (head); \
pos = llist_entry(pos->member.next, type, member))
/*! @} */