56 lines
2.1 KiB
C
56 lines
2.1 KiB
C
/*
|
|
* dqueue.h --
|
|
*
|
|
* Utility module for double ended queues (dqueus).
|
|
* DQueues are stored in a malloced array which grows when it overflows.
|
|
* The head of the queue grows towards lower addresses, and the tail grows
|
|
* up. The array is treated like a cirular ring of size dq_maxSize.
|
|
*
|
|
* *********************************************************************
|
|
* * Copyright (C) 1985, 1990 Regents of the University of California. *
|
|
* * Permission to use, copy, modify, and distribute this *
|
|
* * software and its documentation for any purpose and without *
|
|
* * fee is hereby granted, provided that the above copyright *
|
|
* * notice appear in all copies. The University of California *
|
|
* * makes no representations about the suitability of this *
|
|
* * software for any purpose. It is provided "as is" without *
|
|
* * express or implied warranty. Export of this software outside *
|
|
* * of the United States of America may require an export license. *
|
|
* *********************************************************************
|
|
*
|
|
* rcsid "$Header: /usr/cvsroot/magic-8.0/utils/dqueue.h,v 1.1.1.1 2008/02/03 20:43:50 tim Exp $"
|
|
*
|
|
*/
|
|
|
|
#ifndef _DQUEUE_H
|
|
#define _DQUEUE_H
|
|
|
|
#include "utils/magic.h"
|
|
|
|
/* The dqueue structure, to be manipulated only by the
|
|
* procedures declared in this file.
|
|
*/
|
|
typedef struct {
|
|
int dq_size; /* number of elements in this dqueue */
|
|
int dq_maxSize; /* max capacity of this dqueue */
|
|
int dq_front; /* next empty location at head of dqueue */
|
|
int dq_rear; /* next empty location at tail of dqueue */
|
|
ClientData *dq_data; /* points to an array (filled in by DQInit) */
|
|
} DQueue;
|
|
|
|
|
|
/* Housekeeping for DQueues */
|
|
extern void DQInit(); /* Sets up data in an already allocated DQueue */
|
|
extern void DQFree();
|
|
extern void DQChangeSize();
|
|
extern void DQCopy();
|
|
#define DQIsEmpty(q) ((q)->dq_size == 0)
|
|
|
|
/* Adding and deleting */
|
|
extern void DQPushFront();
|
|
extern void DQPushRear();
|
|
extern ClientData DQPopFront();
|
|
extern ClientData DQPopRear();
|
|
|
|
#endif /* _DQUEUE_H */
|