freebsd-skq/sys/netatm/queue.h
phk c3dd1fa899 Add new files for HARP3
Host ATM Research Platform (HARP), Network Computing Services, Inc.
This software was developed with the support of the Defense Advanced
Research Projects Agency (DARPA).
1998-09-15 08:23:17 +00:00

214 lines
5.4 KiB
C

/*
*
* ===================================
* HARP | Host ATM Research Platform
* ===================================
*
*
* This Host ATM Research Platform ("HARP") file (the "Software") is
* made available by Network Computing Services, Inc. ("NetworkCS")
* "AS IS". NetworkCS does not provide maintenance, improvements or
* support of any kind.
*
* NETWORKCS MAKES NO WARRANTIES OR REPRESENTATIONS, EXPRESS OR IMPLIED,
* INCLUDING, BUT NOT LIMITED TO, IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS FOR A PARTICULAR PURPOSE, AS TO ANY ELEMENT OF THE
* SOFTWARE OR ANY SUPPORT PROVIDED IN CONNECTION WITH THIS SOFTWARE.
* In no event shall NetworkCS be responsible for any damages, including
* but not limited to consequential damages, arising from or relating to
* any use of the Software or related support.
*
* Copyright 1994-1998 Network Computing Services, Inc.
*
* Copies of this Software may be made, however, the above copyright
* notice must be reproduced on all copies.
*
* @(#) $Id: queue.h,v 1.2 1997/05/06 22:14:38 mks Exp $
*
*/
/*
* Core ATM Services
* -----------------
*
* General queueing/linking definitions
*
*/
#ifndef _NETATM_QUEUE_H
#define _NETATM_QUEUE_H
/*
* Structure defining the queue controls for a doubly linked queue
*/
struct q_queue {
caddr_t q_head; /* Head of queue */
caddr_t q_tail; /* Tail of queue */
};
typedef struct q_queue Queue_t;
/*
* Structure defining the queue elements of a doubly linked queue
*/
struct q_elem {
caddr_t q_forw; /* Forward link */
caddr_t q_back; /* Backward link */
};
typedef struct q_elem Qelem_t;
/*
* Macro to add a control block onto the tail of a doubly linked queue
* e = control block to add
* t = control block structure type
* el = name of control block's q_elem field
* q = pointer to queue controls
*/
#define ENQUEUE(e,t,el,q) \
{ \
(e)->el.q_forw = NULL; \
(e)->el.q_back = (q).q_tail; \
if ((q).q_head == NULL) { \
(q).q_head = (caddr_t)(e); \
(q).q_tail = (caddr_t)(e); \
} else { \
((t *)(q).q_tail)->el.q_forw = (caddr_t)(e); \
(q).q_tail = (caddr_t)(e); \
} \
}
/*
* Macro to remove a control block from a doubly linked queue
* e = control block to remove
* t = control block structure type
* el = name of control block's q_elem field
* q = pointer to queue controls
*/
#define DEQUEUE(e,t,el,q) \
{ \
/* Ensure control block is on queue */ \
if ((e)->el.q_forw || (q).q_tail == (caddr_t)(e)) { \
if ((e)->el.q_forw) \
((t *)(e)->el.q_forw)->el.q_back = (e)->el.q_back;\
else \
(q).q_tail = (e)->el.q_back; \
if ((e)->el.q_back) \
((t *)(e)->el.q_back)->el.q_forw = (e)->el.q_forw;\
else \
(q).q_head = (e)->el.q_forw; \
} \
(e)->el.q_back = (e)->el.q_forw = NULL; \
}
/*
* Macro to return the head of a doubly linked queue
* q = pointer to queue controls
* t = control block structure type
*/
#define Q_HEAD(q,t) ((t *)(q).q_head)
/*
* Macro to return the next control block of a doubly linked queue
* e = current control block
* t = control block structure type
* el = name of control block's q_elem field
*/
#define Q_NEXT(e,t,el) ((t *)(e)->el.q_forw)
/*
* Macro to add a control block onto the head of a singly linked chain
* u = control block to add
* t = structure type
* h = head of chain
* l = name of link field
*/
#define LINK2HEAD(u,t,h,l) \
{ \
(u)->l = (h); \
(h) = (u); \
}
/*
* Macro to add a control block onto the tail of a singly linked chain
* u = control block to add
* t = structure type
* h = head of chain
* l = name of link field
*/
#define LINK2TAIL(u,t,h,l) \
{ \
(u)->l = (t *)NULL; \
/* Check for empty chain */ \
if ((h) == (t *)NULL) { \
(h) = (u); \
} else { \
t *tp; \
/* Loop until we find the end of chain */ \
for (tp = (h); tp->l != (t *)NULL; tp = tp->l) \
; \
tp->l = (u); \
} \
}
/*
* Macro to remove a control block from a singly linked chain
* u = control block to unlink
* t = structure type
* h = head of chain
* l = name of link field
*/
#define UNLINK(u,t,h,l) \
{ \
/* Check for control block at head of chain */ \
if ((u) == (h)) { \
(h) = (u)->l; \
} else { \
t *tp; \
/* Loop until we find the control block */ \
for (tp = (h); tp != (t *)NULL; tp = tp->l) { \
if (tp->l == (u)) \
break; \
} \
if (tp) { \
/* Remove it from chain */ \
tp->l = (u)->l; \
} \
} \
(u)->l = (t *)NULL; \
}
/*
* Macro to remove a control block from a singly linked chain and return
* an indication of whether the block was found
* u = control block to unlink
* t = structure type
* h = head of chain
* l = name of link field
* f = flag; 1 => control block found on chain; else 0
*/
#define UNLINKF(u,t,h,l,f) \
{ \
/* Check for control block at head of chain */ \
if ((u) == (h)) { \
(h) = (u)->l; \
(f) = 1; \
} else { \
t *tp; \
/* Loop until we find the control block */ \
for (tp = (h); tp != (t *)NULL; tp = tp->l) { \
if (tp->l == (u)) \
break; \
} \
if (tp) { \
/* Remove it from chain */ \
tp->l = (u)->l; \
(f) = 1; \
} else \
/* It wasn't on the chain */ \
(f) = 0; \
} \
(u)->l = (t *)NULL; \
}
#endif /* _NETATM_QUEUE_H */