bsd/netat/adsp_attention.c

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