#ifndef UBI_DLINKLIST_H #define UBI_DLINKLIST_H /* ========================================================================== ** * ubi_dLinkList.h * * Copyright (C) 1997, 1998 by Christopher R. Hertel * * Email: crh@ubiqx.mn.org * -------------------------------------------------------------------------- ** * This module implements simple doubly-linked lists. * -------------------------------------------------------------------------- ** * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Library General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library 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 * Library General Public License for more details. * * You should have received a copy of the GNU Library General Public * License along with this library; if not, write to the Free * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. * * -------------------------------------------------------------------------- ** * * Log: ubi_dLinkList.h,v * Revision 0.10 1998/07/24 07:30:20 crh * Added the ubi_dlNewList() macro. * * Revision 0.9 1998/06/04 21:29:27 crh * Upper-cased defined constants (eg UBI_BINTREE_H) in some header files. * This is more "standard", and is what people expect. Weird, eh? * * Revision 0.8 1998/06/03 18:06:03 crh * Further fiddling with sys_include.h, which has been moved from the .c file * to the .h file. * * Revision 0.7 1998/06/02 01:38:47 crh * Changed include file name from ubi_null.h to sys_include.h to make it * more generic. * * Revision 0.6 1998/05/20 04:38:05 crh * The C file now includes ubi_null.h. See ubi_null.h for more info. * * Revision 0.5 1998/03/10 02:54:04 crh * Simplified the code and added macros for stack & queue manipulations. * * Revision 0.4 1998/01/03 01:53:44 crh * Added ubi_dlCount() macro. * * Revision 0.3 1997/10/15 03:04:31 crh * Added some handy type casting to the macros. Added AddHere and RemThis * macros. * * Revision 0.2 1997/10/08 03:08:16 crh * Fixed a few forgotten link-ups in Insert(), and fixed the AddHead() * macro, which was passing the wrong value for <After> to Insert(). * * Revision 0.1 1997/10/07 04:34:38 crh * Initial Revision. * * -------------------------------------------------------------------------- ** * This module is similar to the ubi_sLinkList module, but it is neither a * descendant type nor an easy drop-in replacement for the latter. One key * difference is that the ubi_dlRemove() function removes the indicated node, * while the ubi_slRemove() function (in ubi_sLinkList) removes the node * *following* the indicated node. * * ========================================================================== ** */ #include "sys_include.h" /* System-specific includes. */ /* ========================================================================== ** * Typedefs... * * ubi_dlNode - This is the basic node structure. * ubi_dlNodePtr - Pointer to a node. * ubi_dlList - This is the list header structure. * ubi_dlListPtr - Pointer to a List (i.e., a list header structure). * */ typedef struct ubi_dlListNode { struct ubi_dlListNode *Next; struct ubi_dlListNode *Prev; } ubi_dlNode; typedef ubi_dlNode *ubi_dlNodePtr; typedef struct { ubi_dlNodePtr Head; ubi_dlNodePtr Tail; unsigned long count; } ubi_dlList; typedef ubi_dlList *ubi_dlListPtr; /* ========================================================================== ** * Macros... * * ubi_dlNewList - Macro used to declare and initialize a new list in one * swell foop. It is used when defining a variable of * type ubi_dlList. The definition * static ubi_dlNewList( gerbil ); * is translated to * static ubi_dlList gerbil[1] = {{ NULL, NULL, 0 }}; * * ubi_dlCount - Return the number of entries currently in the list. * * ubi_dlAddHead - Add a new node at the head of the list. * ubi_dlAddNext - Add a node following the given node. * ubi_dlAddTail - Add a new node at the tail of the list. * Note: AddTail evaluates the L parameter twice. * * ubi_dlRemHead - Remove the node at the head of the list, if any. * Note: RemHead evaluates the L parameter twice. * ubi_dlRemThis - Remove the indicated node. * ubi_dlRemTail - Remove the node at the tail of the list, if any. * Note: RemTail evaluates the L parameter twice. * * ubi_dlFirst - Return a pointer to the first node in the list, if any. * ubi_dlLast - Return a pointer to the last node in the list, if any. * ubi_dlNext - Given a node, return a pointer to the next node. * ubi_dlPrev - Given a node, return a pointer to the previous node. * * ubi_dlPush - Add a node at the head of the list (synonym of AddHead). * ubi_dlPop - Remove a node at the head of the list (synonym of RemHead). * ubi_dlEnqueue - Add a node at the tail of the list (sysnonym of AddTail). * ubi_dlDequeue - Remove a node at the head of the list (synonym of RemHead). * * Note that all of these provide type casting of the parameters. The * Add and Rem macros are nothing more than nice front-ends to the * Insert and Remove operations. * * Also note that the First, Next and Last macros do no parameter checking! * */ #define ubi_dlNewList( L ) ubi_dlList (L)[1] = {{ NULL, NULL, 0 }} #define ubi_dlCount( L ) (((ubi_dlListPtr)(L))->count) #define ubi_dlAddHead( L, N ) \ ubi_dlInsert( (ubi_dlListPtr)(L), (ubi_dlNodePtr)(N), NULL ) #define ubi_dlAddNext( L, N, A ) \ ubi_dlInsert( (ubi_dlListPtr)(L), \ (ubi_dlNodePtr)(N), \ (ubi_dlNodePtr)(A) ) #define ubi_dlAddTail( L, N ) \ ubi_dlInsert( (ubi_dlListPtr)(L), \ (ubi_dlNodePtr)(N), \ (((ubi_dlListPtr)(L))->Tail) ) #define ubi_dlRemHead( L ) ubi_dlRemove( (ubi_dlListPtr)(L), \ (((ubi_dlListPtr)(L))->Head) ) #define ubi_dlRemThis( L, N ) ubi_dlRemove( (ubi_dlListPtr)(L), \ (ubi_dlNodePtr)(N) ) #define ubi_dlRemTail( L ) ubi_dlRemove( (ubi_dlListPtr)(L), \ (((ubi_dlListPtr)(L))->Tail) ) #define ubi_dlFirst( L ) (((ubi_dlListPtr)(L))->Head) #define ubi_dlLast( L ) (((ubi_dlListPtr)(L))->Tail) #define ubi_dlNext( N ) (((ubi_dlNodePtr)(N))->Next) #define ubi_dlPrev( N ) (((ubi_dlNodePtr)(N))->Prev) #define ubi_dlPush ubi_dlAddHead #define ubi_dlPop ubi_dlRemHead #define ubi_dlEnqueue ubi_dlAddTail #define ubi_dlDequeue ubi_dlRemHead /* ========================================================================== ** * Function prototypes... */ ubi_dlListPtr ubi_dlInitList( ubi_dlListPtr ListPtr ); /* ------------------------------------------------------------------------ ** * Initialize a doubly-linked list header. * * Input: ListPtr - A pointer to the list structure that is to be * initialized for use. * * Output: A pointer to the initialized list header (i.e., same as * <ListPtr>). * * ------------------------------------------------------------------------ ** */ ubi_dlNodePtr ubi_dlInsert( ubi_dlListPtr ListPtr, ubi_dlNodePtr New, ubi_dlNodePtr After ); /* ------------------------------------------------------------------------ ** * Insert a new node into the list. * * Input: ListPtr - A pointer to the list into which the node is to * be inserted. * New - Pointer to the new node. * After - NULL, or a pointer to a node that is already in the * list. * If NULL, then <New> will be added at the head of the * list, else it will be added following <After>. * * Output: A pointer to the node that was inserted into the list (i.e., * the same as <New>). * * ------------------------------------------------------------------------ ** */ ubi_dlNodePtr ubi_dlRemove( ubi_dlListPtr ListPtr, ubi_dlNodePtr Old ); /* ------------------------------------------------------------------------ ** * Remove a node from the list. * * Input: ListPtr - A pointer to the list from which <Old> is to be * removed. * Old - A pointer to the node that is to be removed from the * list. * * Output: A pointer to the node that was removed (i.e., <Old>). * * ------------------------------------------------------------------------ ** */ /* ================================ The End ================================= */ #endif /* UBI_DLINKLIST_H */