/*
 * File      : rtservice.h
 * This file is part of RT-Thread RTOS
 * COPYRIGHT (C) 2006 - 2012, RT-Thread Development Team
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License along
 *  with this program; if not, write to the Free Software Foundation, Inc.,
 *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Change Logs:
 * Date           Author       Notes
 * 2006-03-16     Bernard      the first version
 * 2006-09-07     Bernard      move the kservice APIs to rtthread.h
 * 2007-06-27     Bernard      fix the rt_list_remove bug
 * 2012-03-22     Bernard      rename kservice.h to rtservice.h
 */

#ifndef __RT_SERVICE_H__
#define __RT_SERVICE_H__

#ifdef __cplusplus
extern "C" {
#endif

/**
 * @addtogroup KernelService
 */

/*@{*/

/**
 * @brief initialize a list object
 */
#define RT_LIST_OBJECT_INIT(object) { &(object), &(object) }

/**
 * @brief initialize a list
 *
 * @param l list to be initialized
 */
rt_inline void rt_list_init(rt_list_t *l)
{
    l->next = l->prev = l;
}

/**
 * @brief insert a node after a list
 *
 * @param l list to insert it
 * @param n new node to be inserted
 */
rt_inline void rt_list_insert_after(rt_list_t *l, rt_list_t *n)
{
    l->next->prev = n;
    n->next = l->next;

    l->next = n;
    n->prev = l;
}

/**
 * @brief insert a node before a list
 *
 * @param n new node to be inserted
 * @param l list to insert it
 */
rt_inline void rt_list_insert_before(rt_list_t *l, rt_list_t *n)
{
    l->prev->next = n;
    n->prev = l->prev;

    l->prev = n;
    n->next = l;
}

/**
 * @brief remove node from list.
 * @param n the node to remove from the list.
 */
rt_inline void rt_list_remove(rt_list_t *n)
{
    n->next->prev = n->prev;
    n->prev->next = n->next;

    n->next = n->prev = n;
}

/**
 * @brief tests whether a list is empty
 * @param l the list to test.
 */
rt_inline int rt_list_isempty(const rt_list_t *l)
{
    return l->next == l;
}

/**
 * @brief get the list length
 * @param l the list to get.
 */
rt_inline unsigned int rt_list_len(const rt_list_t *l)
{
    unsigned int len = 0;
    const rt_list_t *p = l;
    while (p->next != l)
    {
        p = p->next;
        len ++;
    }

    return len;
}

/**
 * @brief get the struct for this entry
 * @param node the entry point
 * @param type the type of structure
 * @param member the name of list in structure
 */
#define rt_list_entry(node, type, member) \
    ((type *)((char *)(node) - (unsigned long)(&((type *)0)->member)))

/**
 * rt_list_for_each_entry  -   iterate over list of given type
 * @pos:    the type * to use as a loop cursor.
 * @head:   the head for your list.
 * @member: the name of the list_struct within the struct.
 */
#define rt_list_for_each_entry(pos, head, member)              \
    for (pos = rt_list_entry((head)->next, typeof(*pos), member);  \
         &pos->member != (head);    \
         pos = rt_list_entry(pos->member.next, typeof(*pos), member))

/**
 * rt_list_first_entry - get the first element from a list
 * @ptr:    the list head to take the element from.
 * @type:   the type of the struct this is embedded in.
 * @member: the name of the list_struct within the struct.
 *
 * Note, that list is expected to be not empty.
 */
#define rt_list_first_entry(ptr, type, member) \
    rt_list_entry((ptr)->next, type, member)

#define RT_SLIST_OBJECT_INIT(object) { RT_NULL }

/**
 * @brief initialize a single list
 *
 * @param l the single list to be initialized
 */
rt_inline void rt_slist_init(rt_slist_t *l)
{
    l->next = RT_NULL;
}

rt_inline void rt_slist_append(rt_slist_t *l, rt_slist_t *n)
{
    struct rt_slist_node *node;

    node = l;
    while (node->next) node = node->next;

    /* append the node to the tail */
    node->next = n;
    n->next = RT_NULL;
}

rt_inline void rt_slist_insert(rt_slist_t *l, rt_slist_t *n)
{
    n->next = l->next;
    l->next = n;
}

rt_inline rt_slist_t *rt_slist_remove(rt_slist_t *l, rt_slist_t *n)
{
    /* remove slist head */
    struct rt_slist_node *node = l;
    while (node->next && node->next != n) node = node->next;

    /* remove node */
    if (node->next != (rt_slist_t *)0) node->next = node->next->next;

    return l;
}

rt_inline unsigned int rt_slist_len(const rt_slist_t *l)
{
    unsigned int len = 0;
    const rt_slist_t *list = l->next;
    while (list != RT_NULL)
    {
        list = list->next;
        len ++;
    }

    return len;
}

/**
 * @brief get the struct for this single list node
 * @param node the entry point
 * @param type the type of structure
 * @param member the name of list in structure
 */
#define rt_slist_entry(node, type, member)    \
    ((type *)((char*)(node)-(unsigned long)(&((type *)0)->member)))

/**
 * rt_slist_for_each_entry  -   iterate over single list of given type
 * @node:   the type * to use as a loop cursor.
 * @list:   the head for your single list.
 */
#define rt_slist_foreach(node, list)  \
    for ((node) = (list)->next; (node) != RT_NULL; (node) = (node)->next)

/**
 * rt_container_of - return the member address of ptr, if the type of ptr is the 
 * struct type.
 */
#define rt_container_of(ptr, type, member) \
    ((type *)((char *)(ptr) - (unsigned long)(&((type *)0)->member)))

/*@}*/

#ifdef __cplusplus
}
#endif

#endif