[apple/xnu.git] / bsd / netat / atp_misc.c

/*
 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * The contents of this file constitute Original Code as defined in and
 * are subject to the Apple Public Source License Version 1.1 (the
 * "License").  You may not use this file except in compliance with the
 * License.  Please obtain a copy of the License at
 * http://www.apple.com/publicsource and read it before using this file.
 * 
 * This Original Code and all software distributed under the License are
 * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
 * License for the specific language governing rights and limitations
 * under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */
/*
 *	Copyright (c) 1996-1998 Apple Computer, Inc.
 *	All Rights Reserved.
 */

/*    Modified for MP, 1996 by Tuyen Nguyen
 *   Modified, March 17, 1997 by Tuyen Nguyen for MacOSX.
 */
#include <sys/errno.h>
#include <sys/types.h>
#include <sys/param.h>
#include <machine/spl.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/proc.h>
#include <sys/filedesc.h>
#include <sys/fcntl.h>
#include <sys/mbuf.h>
#include <sys/ioctl.h>
#include <sys/malloc.h>
#include <sys/socket.h>

#include <netat/sysglue.h>
#include <netat/appletalk.h>
#include <netat/ddp.h>
#include <netat/at_pcb.h>
#include <netat/atp.h>
#include <netat/debug.h>

extern atlock_t atpgen_lock;
void atp_free();
void atp_send(struct atp_trans *);

/*
 *	The request timer retries a request, if all retries are used up
 *		it returns a NAK
 */

void
atp_req_timeout(trp)
register struct atp_trans *trp;
{
	int s;
	register gbuf_t *m;
	gref_t *gref;
	struct atp_state *atp;
	struct atp_trans *ctrp;

	if ((atp = trp->tr_queue) == 0)
		return;
	ATDISABLE(s, atp->atp_lock);
	if (atp->atp_flags & ATP_CLOSING) {
		ATENABLE(s, atp->atp_lock);
		return;
	}
	for (ctrp = atp->atp_trans_wait.head; ctrp; ctrp = ctrp->tr_list.next) {
		if (ctrp == trp)
			break;
	}
	if (ctrp != trp) {
		ATENABLE(s, atp->atp_lock);
		return;
	}

	if ((m = gbuf_cont(trp->tr_xmt)) == NULL)
	        m = trp->tr_xmt;               /* issued via the new interface */

	if (trp->tr_retry == 0) {
		trp->tr_state = TRANS_FAILED;
		if (m == trp->tr_xmt) {
			trp->tr_xmt = NULL;
l_notify:
				gbuf_wset(m,1);
				*gbuf_rptr(m) = 99;
				gbuf_set_type(m, MSG_DATA);
				gref = trp->tr_queue->atp_gref;
				ATENABLE(s, atp->atp_lock);
				atalk_putnext(gref, m);

			return;
		}
		dPrintf(D_M_ATP_LOW,D_L_INFO, ("atp_req_timeout: skt=%d\n",
			trp->tr_local_socket));
		m = trp->tr_xmt;
		switch(((ioc_t *)(gbuf_rptr(trp->tr_xmt)))->ioc_cmd) {
		case AT_ATP_ISSUE_REQUEST:
			trp->tr_xmt = NULL;
			if (trp->tr_queue->dflag)
				((ioc_t *)gbuf_rptr(m))->ioc_cmd = AT_ATP_REQUEST_COMPLETE;
			else if (trp->tr_bdsp == NULL) {
				ATENABLE(s, atp->atp_lock);
				gbuf_freem(m);
				if (trp->tr_rsp_wait)
					wakeup(&trp->tr_event);
				break;
			}
			ATENABLE(s, atp->atp_lock);
			atp_iocnak(trp->tr_queue, m, ETIMEDOUT);
			atp_free(trp);
			return;

		case AT_ATP_ISSUE_REQUEST_NOTE:
		case AT_ATP_ISSUE_REQUEST_TICKLE:
			trp->tr_xmt = gbuf_cont(m);
			gbuf_cont(m) = NULL;
			goto l_notify;
		}
	} else {
		(AT_ATP_HDR(m))->bitmap = trp->tr_bitmap;

		if (trp->tr_retry != (unsigned int) ATP_INFINITE_RETRIES)
			trp->tr_retry--;
		ATENABLE(s, atp->atp_lock);
		atp_send(trp);
	}
}


/*
 *	atp_free frees up a request, cleaning up the queues and freeing
 *		the request packet
 *      always called at 'lock'
 */

void atp_free(trp)
register struct atp_trans *trp;
{	
	register struct atp_state *atp;
	register int i;
	int s;
	
	dPrintf(D_M_ATP_LOW, D_L_TRACE,
		("atp_free: freeing trp 0x%x\n", (u_int) trp));

	ATDISABLE(s, atpgen_lock);

	if (trp->tr_state == TRANS_ABORTING) {
		ATP_Q_REMOVE(atp_trans_abort, trp, tr_list);
		trp->tr_state = TRANS_DONE;
	}
	else {
		if (trp->tr_tmo_func)
	        atp_untimout(atp_req_timeout, trp);

		atp = trp->tr_queue;
		ATP_Q_REMOVE(atp->atp_trans_wait, trp, tr_list);
	
		if (trp->tr_xmt) {
		  	gbuf_freem(trp->tr_xmt);
			trp->tr_xmt = NULL;
		}
		for (i = 0; i < 8; i++) {
		        if (trp->tr_rcv[i]) {
			        gbuf_freem(trp->tr_rcv[i]);
				trp->tr_rcv[i] = NULL;
			}
		}
		if (trp->tr_bdsp) {
			gbuf_freem(trp->tr_bdsp);
			trp->tr_bdsp = NULL;
		}
		
		if (trp->tr_rsp_wait) {
			trp->tr_state = TRANS_ABORTING;
			ATP_Q_APPEND(atp_trans_abort, trp, tr_list);
			wakeup(&trp->tr_event);
			ATENABLE(s, atpgen_lock);
			return;
		}
	}
	
	ATENABLE(s, atpgen_lock);
	atp_trans_free(trp);
} /* atp_free */


/*
 *	atp_send transmits a request packet by queuing it (if it isn't already) and
 *		scheduling the queue
 */

void atp_send(trp)
register struct atp_trans *trp;
{
	gbuf_t *m;
	struct atp_state *atp;

	dPrintf(D_M_ATP_LOW, D_L_OUTPUT, ("atp_send: trp=0x%x, loc=%d\n",
		(u_int) trp->tr_queue, trp->tr_local_socket));

	if ((atp = trp->tr_queue) != 0) {
	  if (trp->tr_state == TRANS_TIMEOUT) {
	    if ((m = gbuf_cont(trp->tr_xmt)) == NULL)
	        m = trp->tr_xmt;

	    /*
	     *	Now either release the transaction or start the timer
	     */
	    if (!trp->tr_retry && !trp->tr_bitmap && !trp->tr_xo) {
		m = (gbuf_t *)gbuf_copym(m);
		atp_x_done(trp);
	    } else {
		m = (gbuf_t *)gbuf_dupm(m);

		atp_timout(atp_req_timeout, trp, trp->tr_timeout);
	    }

	    if (m) {	
	        trace_mbufs(D_M_ATP_LOW, "  m", m);
		DDP_OUTPUT(m);
	    }
	}
  }
}


/*
 *	atp_reply sends all the available messages in the bitmap again
 *		by queueing us to the write service routine
 */

void atp_reply(rcbp)
register struct atp_rcb *rcbp;
{
	register struct atp_state *atp;
	register int i;
	int s;

  if ((atp = rcbp->rc_queue) != 0) {
	ATDISABLE(s, atp->atp_lock);
	for (i = 0; i < rcbp->rc_pktcnt; i++) {
		if (rcbp->rc_bitmap&atp_mask[i])
			rcbp->rc_snd[i] = 1;
		else
			rcbp->rc_snd[i] = 0;
	}
        if (rcbp->rc_rep_waiting == 0) {
	        rcbp->rc_state = RCB_SENDING;
	        rcbp->rc_rep_waiting = 1;
	        ATENABLE(s, atp->atp_lock);
	        atp_send_replies(atp, rcbp);
	} else
	ATENABLE(s, atp->atp_lock);
  }
}


/*
 *	The rcb timer just frees the rcb, this happens when we missed a release for XO
 */

void atp_rcb_timer()
{  
	int s;
        register struct atp_rcb *rcbp;
	register struct atp_rcb *next_rcbp;
	extern   struct atp_rcb_qhead atp_need_rel;
	extern struct atp_trans *trp_tmo_rcb;
	struct timeval timenow;

l_again:
	ATDISABLE(s, atpgen_lock);
	getmicrouptime(&timenow);
	for (rcbp = atp_need_rel.head; rcbp; rcbp = next_rcbp) {
	        next_rcbp = rcbp->rc_tlist.next;

	        if (abs(timenow.tv_sec - rcbp->rc_timestamp) > 30) {
		        ATENABLE(s, atpgen_lock);
		        atp_rcb_free(rcbp);
		        goto l_again;
		}
	}
	ATENABLE(s, atpgen_lock);
	atp_timout(atp_rcb_timer, trp_tmo_rcb, 10 * HZ);
}

atp_iocack(atp, m)
struct   atp_state *atp;
register gbuf_t *m;
{
	if (gbuf_type(m) == MSG_IOCTL)
		gbuf_set_type(m, MSG_IOCACK);
	if (gbuf_cont(m))
		((ioc_t *)gbuf_rptr(m))->ioc_count = gbuf_msgsize(gbuf_cont(m));
	else
		((ioc_t *)gbuf_rptr(m))->ioc_count = 0;

	if (atp->dflag)
		asp_ack_reply(atp->atp_gref, m);
	else
		atalk_putnext(atp->atp_gref, m);
}

atp_iocnak(atp, m, err)
struct   atp_state *atp;
register gbuf_t *m;
register int err;
{
	if (gbuf_type(m) == MSG_IOCTL)
		gbuf_set_type(m, MSG_IOCNAK);
	((ioc_t *)gbuf_rptr(m))->ioc_count = 0;
	((ioc_t *)gbuf_rptr(m))->ioc_error = err ? err : ENXIO;
	((ioc_t *)gbuf_rptr(m))->ioc_rval = -1;
	if (gbuf_cont(m)) {
		gbuf_freem(gbuf_cont(m));
		gbuf_cont(m) = NULL;
	}

	if (atp->dflag)
		asp_nak_reply(atp->atp_gref, m);
	else
		atalk_putnext(atp->atp_gref, m);
}

/*
 *	Generate a transaction id for a socket
 */
static int lasttid;
atp_tid(atp)
register struct atp_state *atp;
{
	register int i;
	register struct atp_trans *trp;
	int s;

	ATDISABLE(s, atpgen_lock);
	for (i = lasttid;;) {
		i = (i+1)&0xffff;

		for (trp = atp->atp_trans_wait.head; trp; trp = trp->tr_list.next) {
		        if (trp->tr_tid == i)
			        break;
		}
		if (trp == NULL) {
			lasttid = i;
			ATENABLE(s, atpgen_lock);
			return(i);
		}
	}
}
Commit	Line	Data
1c79356b A	1	/*
	2	* Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
	3	*
	4	* @APPLE_LICENSE_HEADER_START@
	5	*
e5568f75 A	6	* The contents of this file constitute Original Code as defined in and
	7	* are subject to the Apple Public Source License Version 1.1 (the
	8	* "License"). You may not use this file except in compliance with the
	9	* License. Please obtain a copy of the License at
	10	* http://www.apple.com/publicsource and read it before using this file.
1c79356b	11	*
e5568f75 A	12	* This Original Code and all software distributed under the License are
e5568f75 A	13	* distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
1c79356b A	14	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
1c79356b A	15	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
e5568f75 A	16	* FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
	17	* License for the specific language governing rights and limitations
	18	* under the License.
1c79356b A	19	*
	20	* @APPLE_LICENSE_HEADER_END@
	21	*/
	22	/*
	23	* Copyright (c) 1996-1998 Apple Computer, Inc.
	24	* All Rights Reserved.
	25	*/
	26
	27	/* Modified for MP, 1996 by Tuyen Nguyen
	28	* Modified, March 17, 1997 by Tuyen Nguyen for MacOSX.
	29	*/
	30	#include <sys/errno.h>
	31	#include <sys/types.h>
	32	#include <sys/param.h>
	33	#include <machine/spl.h>
	34	#include <sys/systm.h>
	35	#include <sys/kernel.h>
	36	#include <sys/proc.h>
	37	#include <sys/filedesc.h>
	38	#include <sys/fcntl.h>
	39	#include <sys/mbuf.h>
	40	#include <sys/ioctl.h>
	41	#include <sys/malloc.h>
	42	#include <sys/socket.h>
	43
	44	#include <netat/sysglue.h>
	45	#include <netat/appletalk.h>
	46	#include <netat/ddp.h>
	47	#include <netat/at_pcb.h>
	48	#include <netat/atp.h>
	49	#include <netat/debug.h>
	50
	51	extern atlock_t atpgen_lock;
	52	void atp_free();
	53	void atp_send(struct atp_trans *);
	54
	55	/*
	56	* The request timer retries a request, if all retries are used up
	57	* it returns a NAK
	58	*/
	59
	60	void
	61	atp_req_timeout(trp)
	62	register struct atp_trans *trp;
	63	{
	64	int s;
	65	register gbuf_t *m;
	66	gref_t *gref;
	67	struct atp_state *atp;
	68	struct atp_trans *ctrp;
	69
	70	if ((atp = trp->tr_queue) == 0)
	71	return;
	72	ATDISABLE(s, atp->atp_lock);
	73	if (atp->atp_flags & ATP_CLOSING) {
	74	ATENABLE(s, atp->atp_lock);
	75	return;
	76	}
	77	for (ctrp = atp->atp_trans_wait.head; ctrp; ctrp = ctrp->tr_list.next) {
	78	if (ctrp == trp)
	79	break;
	80	}
	81	if (ctrp != trp) {
	82	ATENABLE(s, atp->atp_lock);
83	return;
84	}
85
86	if ((m = gbuf_cont(trp->tr_xmt)) == NULL)
87	m = trp->tr_xmt; /* issued via the new interface */
88
89	if (trp->tr_retry == 0) {
90	trp->tr_state = TRANS_FAILED;
91	if (m == trp->tr_xmt) {
92	trp->tr_xmt = NULL;
93	l_notify:
94	gbuf_wset(m,1);
95	*gbuf_rptr(m) = 99;
96	gbuf_set_type(m, MSG_DATA);
97	gref = trp->tr_queue->atp_gref;
98	ATENABLE(s, atp->atp_lock);
99	atalk_putnext(gref, m);
100
101	return;
102	}
103	dPrintf(D_M_ATP_LOW,D_L_INFO, ("atp_req_timeout: skt=%d\n",
104	trp->tr_local_socket));
105	m = trp->tr_xmt;
106	switch(((ioc_t *)(gbuf_rptr(trp->tr_xmt)))->ioc_cmd) {
107	case AT_ATP_ISSUE_REQUEST:
108	trp->tr_xmt = NULL;
109	if (trp->tr_queue->dflag)
110	((ioc_t *)gbuf_rptr(m))->ioc_cmd = AT_ATP_REQUEST_COMPLETE;
111	else if (trp->tr_bdsp == NULL) {
112	ATENABLE(s, atp->atp_lock);
113	gbuf_freem(m);
114	if (trp->tr_rsp_wait)
9bccf70c	115	wakeup(&trp->tr_event);
1c79356b A	116	break;
	117	}
	118	ATENABLE(s, atp->atp_lock);
	119	atp_iocnak(trp->tr_queue, m, ETIMEDOUT);
	120	atp_free(trp);
	121	return;
	122
	123	case AT_ATP_ISSUE_REQUEST_NOTE:
	124	case AT_ATP_ISSUE_REQUEST_TICKLE:
	125	trp->tr_xmt = gbuf_cont(m);
	126	gbuf_cont(m) = NULL;
	127	goto l_notify;
	128	}
	129	} else {
	130	(AT_ATP_HDR(m))->bitmap = trp->tr_bitmap;
	131
	132	if (trp->tr_retry != (unsigned int) ATP_INFINITE_RETRIES)
	133	trp->tr_retry--;
	134	ATENABLE(s, atp->atp_lock);
	135	atp_send(trp);
	136	}
	137	}
	138
	139
	140	/*
	141	* atp_free frees up a request, cleaning up the queues and freeing
	142	* the request packet
	143	* always called at 'lock'
	144	*/
	145
	146	void atp_free(trp)
	147	register struct atp_trans *trp;
0b4e3aa0	148	{
1c79356b A	149	register struct atp_state *atp;
	150	register int i;
	151	int s;
	152
	153	dPrintf(D_M_ATP_LOW, D_L_TRACE,
	154	("atp_free: freeing trp 0x%x\n", (u_int) trp));
1c79356b	155
0b4e3aa0	156	ATDISABLE(s, atpgen_lock);
1c79356b	157
0b4e3aa0 A	158	if (trp->tr_state == TRANS_ABORTING) {
	159	ATP_Q_REMOVE(atp_trans_abort, trp, tr_list);
	160	trp->tr_state = TRANS_DONE;
1c79356b	161	}
0b4e3aa0 A	162	else {
	163	if (trp->tr_tmo_func)
	164	atp_untimout(atp_req_timeout, trp);
	165
	166	atp = trp->tr_queue;
	167	ATP_Q_REMOVE(atp->atp_trans_wait, trp, tr_list);
	168
	169	if (trp->tr_xmt) {
	170	gbuf_freem(trp->tr_xmt);
	171	trp->tr_xmt = NULL;
	172	}
	173	for (i = 0; i < 8; i++) {
	174	if (trp->tr_rcv[i]) {
	175	gbuf_freem(trp->tr_rcv[i]);
	176	trp->tr_rcv[i] = NULL;
	177	}
	178	}
	179	if (trp->tr_bdsp) {
	180	gbuf_freem(trp->tr_bdsp);
	181	trp->tr_bdsp = NULL;
	182	}
	183
	184	if (trp->tr_rsp_wait) {
	185	trp->tr_state = TRANS_ABORTING;
	186	ATP_Q_APPEND(atp_trans_abort, trp, tr_list);
9bccf70c	187	wakeup(&trp->tr_event);
0b4e3aa0 A	188	ATENABLE(s, atpgen_lock);
0b4e3aa0 A	189	return;
1c79356b A	190	}
1c79356b A	191	}
0b4e3aa0	192
1c79356b A	193	ATENABLE(s, atpgen_lock);
1c79356b A	194	atp_trans_free(trp);
1c79356b A	195	} /* atp_free */
	196
	197
	198	/*
	199	* atp_send transmits a request packet by queuing it (if it isn't already) and
	200	* scheduling the queue
	201	*/
	202
	203	void atp_send(trp)
	204	register struct atp_trans *trp;
	205	{
	206	gbuf_t *m;
	207	struct atp_state *atp;
	208
	209	dPrintf(D_M_ATP_LOW, D_L_OUTPUT, ("atp_send: trp=0x%x, loc=%d\n",
	210	(u_int) trp->tr_queue, trp->tr_local_socket));
	211
	212	if ((atp = trp->tr_queue) != 0) {
	213	if (trp->tr_state == TRANS_TIMEOUT) {
	214	if ((m = gbuf_cont(trp->tr_xmt)) == NULL)
	215	m = trp->tr_xmt;
	216
	217	/*
	218	* Now either release the transaction or start the timer
	219	*/
	220	if (!trp->tr_retry && !trp->tr_bitmap && !trp->tr_xo) {
	221	m = (gbuf_t *)gbuf_copym(m);
	222	atp_x_done(trp);
	223	} else {
	224	m = (gbuf_t *)gbuf_dupm(m);
	225
	226	atp_timout(atp_req_timeout, trp, trp->tr_timeout);
	227	}
	228
	229	if (m) {
	230	trace_mbufs(D_M_ATP_LOW, " m", m);
	231	DDP_OUTPUT(m);
	232	}
	233	}
	234	}
	235	}
	236
	237
	238	/*
	239	* atp_reply sends all the available messages in the bitmap again
	240	* by queueing us to the write service routine
	241	*/
	242
	243	void atp_reply(rcbp)
	244	register struct atp_rcb *rcbp;
	245	{
	246	register struct atp_state *atp;
	247	register int i;
	248	int s;
	249
	250	if ((atp = rcbp->rc_queue) != 0) {
	251	ATDISABLE(s, atp->atp_lock);
	252	for (i = 0; i < rcbp->rc_pktcnt; i++) {
	253	if (rcbp->rc_bitmap&atp_mask[i])
	254	rcbp->rc_snd[i] = 1;
	255	else
	256	rcbp->rc_snd[i] = 0;
	257	}
	258	if (rcbp->rc_rep_waiting == 0) {
259	rcbp->rc_state = RCB_SENDING;
260	rcbp->rc_rep_waiting = 1;
261	ATENABLE(s, atp->atp_lock);
262	atp_send_replies(atp, rcbp);
263	} else
264	ATENABLE(s, atp->atp_lock);
265	}
266	}
267
268
269	/*
270	* The rcb timer just frees the rcb, this happens when we missed a release for XO
271	*/
272
273	void atp_rcb_timer()
274	{
275	int s;
276	register struct atp_rcb *rcbp;
277	register struct atp_rcb *next_rcbp;
278	extern struct atp_rcb_qhead atp_need_rel;
279	extern struct atp_trans *trp_tmo_rcb;
91447636	280	struct timeval timenow;
1c79356b A	281
	282	l_again:
	283	ATDISABLE(s, atpgen_lock);
91447636	284	getmicrouptime(&timenow);
1c79356b A	285	for (rcbp = atp_need_rel.head; rcbp; rcbp = next_rcbp) {
	286	next_rcbp = rcbp->rc_tlist.next;
	287
91447636	288	if (abs(timenow.tv_sec - rcbp->rc_timestamp) > 30) {
1c79356b A	289	ATENABLE(s, atpgen_lock);
	290	atp_rcb_free(rcbp);
	291	goto l_again;
	292	}
	293	}
	294	ATENABLE(s, atpgen_lock);
	295	atp_timout(atp_rcb_timer, trp_tmo_rcb, 10 * HZ);
	296	}
	297
	298	atp_iocack(atp, m)
	299	struct atp_state *atp;
	300	register gbuf_t *m;
	301	{
	302	if (gbuf_type(m) == MSG_IOCTL)
	303	gbuf_set_type(m, MSG_IOCACK);
	304	if (gbuf_cont(m))
	305	((ioc_t *)gbuf_rptr(m))->ioc_count = gbuf_msgsize(gbuf_cont(m));
	306	else
	307	((ioc_t *)gbuf_rptr(m))->ioc_count = 0;
	308
	309	if (atp->dflag)
	310	asp_ack_reply(atp->atp_gref, m);
	311	else
	312	atalk_putnext(atp->atp_gref, m);
	313	}
	314
	315	atp_iocnak(atp, m, err)
	316	struct atp_state *atp;
	317	register gbuf_t *m;
	318	register int err;
	319	{
	320	if (gbuf_type(m) == MSG_IOCTL)
	321	gbuf_set_type(m, MSG_IOCNAK);
	322	((ioc_t *)gbuf_rptr(m))->ioc_count = 0;
	323	((ioc_t *)gbuf_rptr(m))->ioc_error = err ? err : ENXIO;
	324	((ioc_t *)gbuf_rptr(m))->ioc_rval = -1;
	325	if (gbuf_cont(m)) {
	326	gbuf_freem(gbuf_cont(m));
	327	gbuf_cont(m) = NULL;
	328	}
	329
	330	if (atp->dflag)
	331	asp_nak_reply(atp->atp_gref, m);
	332	else
	333	atalk_putnext(atp->atp_gref, m);
	334	}
	335
	336	/*
	337	* Generate a transaction id for a socket
	338	*/
	339	static int lasttid;
	340	atp_tid(atp)
	341	register struct atp_state *atp;
	342	{
	343	register int i;
	344	register struct atp_trans *trp;
	345	int s;
	346
	347	ATDISABLE(s, atpgen_lock);
	348	for (i = lasttid;;) {
	349	i = (i+1)&0xffff;
	350
	351	for (trp = atp->atp_trans_wait.head; trp; trp = trp->tr_list.next) {
	352	if (trp->tr_tid == i)
353	break;
354	}
355	if (trp == NULL) {
356	lasttid = i;
357	ATENABLE(s, atpgen_lock);
358	return(i);
359	}
360	}
361	}