bsd/netat/adsp_attention.c

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
   7  *
   8  * This file contains Original Code and/or Modifications of Original Code
   9  * as defined in and that are subject to the Apple Public Source License
  10  * Version 2.0 (the 'License'). You may not use this file except in
  11  * compliance with the License. Please obtain a copy of the License at
  12  * http://www.opensource.apple.com/apsl/ and read it before using this
  13  * file.
  14  *
  15  * The Original Code and all software distributed under the License are
  16  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  17  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  18  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  20  * Please see the License for the specific language governing rights and
  21  * limitations under the License.
  22  *
  23  * @APPLE_LICENSE_HEADER_END@
  24  */
  25 /*
  26  * dspAttention.c
  27  *
  28  * From Mike Shoemaker v01.05  03/16/90 mbs
  29  */
  30 /*
  31  * Change log:
  32  *   06/29/95 - Modified to handle flow control for writing (Tuyen Nguyen)
  33  *    Modified for MP, 1996 by Tuyen Nguyen
  34  *   Modified, April 9, 1997 by Tuyen Nguyen for MacOSX.
  35  */
  36
  37 #include <sys/errno.h>
  38 #include <sys/types.h>
  39 #include <sys/param.h>
  40 #include <machine/spl.h>
  41 #include <sys/systm.h>
  42 #include <sys/kernel.h>
  43 #include <sys/proc.h>
  44 #include <sys/filedesc.h>
  45 #include <sys/fcntl.h>
  46 #include <sys/mbuf.h>
  47 #include <sys/socket.h>
  48
  49 #include <netat/sysglue.h>
  50 #include <netat/appletalk.h>
  51 #include <netat/at_pcb.h>
  52 #include <netat/debug.h>
  53 #include <netat/adsp.h>
  54 #include <netat/adsp_internal.h>
  55
  56 /*
  57  * dspAttention
  58  *
  59  * INPUTS:
  60  *      --> ccbRefNum           refnum of connection end
  61  *      --> attnCode            client attention code
  62  *      --> attnSize            size in bytes of attention data
  63  *      --> attnData            pointer to attention data
  64  *      --> attnInterval        attention retransmit interval
  65  *                              (ignored by ADSP 1.5 & up)
  66  *
  67  * OUTPUTS:
  68  *      none
  69  *
  70  * ERRORS:
  71  *      errRefNum               bad connection refnum
  72  *      errState                connection is not open
  73  *      errAttention            attention message too long
  74  *      errAborted              request aborted by Remove or Close call
  75  */
  76 int adspAttention(sp, pb)       /* (DSPPBPtr pb) */
  77     register struct adspcmd *pb;
  78     register CCBPtr sp;
  79 {
  80     int s;
  81     register gbuf_t *mp, *nmp;
  82     unsigned char uerr;
  83
  84     if (sp == 0) {
  85         pb->ioResult = errRefNum;
  86         return EINVAL;
  87     }
  88
  89     if (sp->state != sOpen) {   /* If we're not open, tell user to go away */
  90         pb->ioResult = errState;
  91         uerr = ENOTCONN;
  92 l_err:
  93         atalk_notify(sp->gref, uerr);
  94         gbuf_freem(pb->mp);
  95         return 0;
  96     }
  97
  98     if (pb->u.attnParams.attnSize > attnBufSize) /* If data too big, bye-bye */
  99     {
 100         pb->ioResult = errAttention;
 101         uerr = ERANGE;
 102         goto l_err;
 103     }
 104
 105     /* The 1st mbuf in the pb->mp chain (mp) is the adspcmd structure.
 106        The 2nd mbuf (nmp) will be the beginning of the data. */
 107     mp = pb->mp;
 108     if (pb->u.attnParams.attnSize) {
 109         nmp = gbuf_cont(mp);
 110         if (gbuf_len(mp) > sizeof(struct adspcmd)) {
 111             if ((nmp = gbuf_dupb(mp)) == 0) {
 112                 gbuf_wset(mp, sizeof(struct adspcmd));
 113                 uerr = ENOBUFS;
 114                 goto l_err;
 115             }
 116             gbuf_wset(mp, sizeof(struct adspcmd));
 117             gbuf_rinc(nmp, sizeof(struct adspcmd));
 118             gbuf_cont(nmp) = gbuf_cont(mp);
 119             gbuf_cont(mp) = nmp;
 120         }
 121     }
 122     pb->ioDirection = 1;        /* outgoing attention data */
 123     ATDISABLE(s, sp->lock);
 124     if (sp->sapb) {             /* Pending attentions already? */
 125         qAddToEnd(&sp->sapb, pb); /* Just add to end of queue */
 126         ATENABLE(s, sp->lock);
 127     } else {
 128         sp->sendAttnData = 1;   /* Start off this attention */
 129         pb->qLink = 0;
 130         sp->sapb = pb;
 131         ATENABLE(s, sp->lock);
 132         CheckSend(sp);
 133     }
 134     pb->ioResult = 1;   /* indicate that the IO is not complete */
 135     return 0;
 136 }