libexec/xtend/status.c

   1 /*-
   2  * Copyright (c) 1992, 1993, 1995 Eugene W. Stark
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by Eugene W. Stark.
  16  * 4. The name of the author may not be used to endorse or promote products
  17  *    derived from this software without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY EUGENE W. STARK (THE AUTHOR) ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
  23  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  24  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  25  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  *
  31  * $FreeBSD: src/libexec/xtend/status.c,v 1.8 1999/08/28 00:10:30 peter Exp $
  32  * $DragonFly: src/libexec/xtend/status.c,v 1.3 2003/11/14 03:54:32 dillon Exp $
  33  */
  34
  35 #include <stdio.h>
  36 #include <unistd.h>
  37 #include <sys/param.h>
  38 #include <sys/stat.h>
  39 #include "xtend.h"
  40 #include "xten.h"
  41 #include "paths.h"
  42
  43 void printstatus (FILE *, STATUS *);
  44
  45 /*
  46  * Initialize the status table from the status files
  47  */
  48
  49 void
  50 initstatus()
  51 {
  52   if(lseek(status, 0, SEEK_SET) != 0) {
  53     fprintf(Log, "%s:  Seek error on status file\n", thedate());
  54     return;
  55   }
  56   if(read(status, Status, 16*16*sizeof(STATUS)) != 16*16*sizeof(STATUS)) {
  57         fprintf(Log, "%s:  Read error on status file\n", thedate());
  58         return;
  59   }
  60 }
  61
  62 /*
  63  * Checkpoint status of any devices whose status has changed
  64  * and notify anyone monitoring those devices.
  65  */
  66
  67 void
  68 checkpoint_status()
  69 {
  70   int h, i, k, offset;
  71
  72   offset = 0;
  73   for(h = 0; h < 16; h++) {
  74     for(i = 0; i < 16; i++) {
  75       if(Status[h][i].changed) {
  76         if(lseek(status, offset, SEEK_SET) != offset) {
  77           fprintf(Log, "%s:  Seek error on status file\n", thedate());
  78         } else {
  79           if(write(status, &Status[h][i], sizeof(STATUS)) != sizeof(STATUS)) {
  80             fprintf(Log, "%s:  Write error on status file\n", thedate());
  81           }
  82         }
  83         Status[h][i].changed = 0;
  84         for(k = 0; k < MAXMON; k++) {
  85           if(Monitor[k].inuse
  86              && Monitor[k].house == h && Monitor[k].unit == i) {
  87             /*
  88              * Arrange to catch SIGPIPE in case client has gone away.
  89              */
  90             extern int client;
  91             extern void clientgone();
  92             void (*prev)();
  93
  94             client = k;
  95             prev = signal(SIGPIPE, clientgone);
  96             printstatus(Monitor[k].user, &Status[h][i]);
  97             fflush(Monitor[k].user);
  98             signal(SIGPIPE, prev);
  99           }
 100         }
 101       }
 102       offset += sizeof(STATUS);
 103     }
 104   }
 105 }
 106
 107 int client;
 108
 109 void clientgone()
 110 {
 111     fprintf(Log, "%s:  Deleting monitor table entry %d, client gone\n", thedate(), client);
 112     fclose(Monitor[client].user);
 113     Monitor[client].inuse = 0;
 114 }