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Diffstat (limited to 'sys/netatm/queue.h')
| -rw-r--r-- | sys/netatm/queue.h | 213 |
1 files changed, 213 insertions, 0 deletions
diff --git a/sys/netatm/queue.h b/sys/netatm/queue.h new file mode 100644 index 0000000..8a8febf --- /dev/null +++ b/sys/netatm/queue.h @@ -0,0 +1,213 @@ +/* + * + * =================================== + * 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 */ |
