osd-contiki/core/lib/list.h
adamdunkels 3ae774c91a Added a way to for specifying lists as parts of structs. These lists
must be initialized with a special LIST_STRUCT_INIT() call before
using.
2010-09-13 13:31:00 +00:00

161 lines
5.4 KiB
C

/** \addtogroup lib
@{ */
/**
* \defgroup list Linked list library
*
* The linked list library provides a set of functions for
* manipulating linked lists.
*
* A linked list is made up of elements where the first element \b
* must be a pointer. This pointer is used by the linked list library
* to form lists of the elements.
*
* Lists are declared with the LIST() macro. The declaration specifies
* the name of the list that later is used with all list functions.
*
* Lists can be manipulated by inserting or removing elements from
* either sides of the list (list_push(), list_add(), list_pop(),
* list_chop()). A specified element can also be removed from inside a
* list with list_remove(). The head and tail of a list can be
* extracted using list_head() and list_tail(), respectively.
*
* @{
*/
/**
* \file
* Linked list manipulation routines.
* \author Adam Dunkels <adam@sics.se>
*
*
*/
/*
* Copyright (c) 2004, Swedish Institute of Computer Science.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* This file is part of the Contiki operating system.
*
* Author: Adam Dunkels <adam@sics.se>
*
* $Id: list.h,v 1.5 2010/09/13 13:31:00 adamdunkels Exp $
*/
#ifndef __LIST_H__
#define __LIST_H__
#define LIST_CONCAT2(s1, s2) s1##s2
#define LIST_CONCAT(s1, s2) LIST_CONCAT2(s1, s2)
/**
* Declare a linked list.
*
* This macro declares a linked list with the specified \c type. The
* type \b must be a structure (\c struct) with its first element
* being a pointer. This pointer is used by the linked list library to
* form the linked lists.
*
* The list variable is declared as static to make it easy to use in a
* single C module without unnecessarily exporting the name to other
* modules.
*
* \param name The name of the list.
*/
#define LIST(name) \
static void *LIST_CONCAT(name,_list) = NULL; \
static list_t name = (list_t)&LIST_CONCAT(name,_list)
/**
* Declare a linked list inside a structure declaraction.
*
* This macro declares a linked list with the specified \c type. The
* type \b must be a structure (\c struct) with its first element
* being a pointer. This pointer is used by the linked list library to
* form the linked lists.
*
* Internally, the list is defined as two items: the list itself and a
* pointer to the list. The pointer has the name of the parameter to
* the macro and the name of the list is a concatenation of the name
* and the suffix "_list". The pointer must point to the list for the
* list to work. Thus the list must be initialized before using.
*
* The list is initialized with the LIST_STRUCT_INIT() macro.
*
* \param name The name of the list.
*/
#define LIST_STRUCT(name) \
void *LIST_CONCAT(name,_list); \
list_t name
/**
* Initialize a linked list that is part of a structure.
*
* This macro sets up the internal pointers in a list that has been
* defined as part of a struct. This macro must be called before using
* the list.
*
* \param struct_ptr A pointer to the struct
* \param name The name of the list.
*/
#define LIST_STRUCT_INIT(struct_ptr, name) \
do { \
(struct_ptr)->name = &((struct_ptr)->LIST_CONCAT(name,_list)); \
(struct_ptr)->LIST_CONCAT(name,_list) = NULL; \
list_init((struct_ptr)->name); \
} while(0)
/**
* The linked list type.
*
*/
typedef void ** list_t;
void list_init(list_t list);
void * list_head(list_t list);
void * list_tail(list_t list);
void * list_pop (list_t list);
void list_push(list_t list, void *item);
void * list_chop(list_t list);
void list_add(list_t list, void *item);
void list_remove(list_t list, void *item);
int list_length(list_t list);
void list_copy(list_t dest, list_t src);
void list_insert(list_t list, void *previtem, void *newitem);
void * list_item_next(void *item);
#endif /* __LIST_H__ */
/** @} */
/** @} */